Imported from libpng-0.99e.tar

CHANGES

@@ -200,3 +200,47 @@ version 0.98 [January, 1998]
       PNG_TIME_RFC1152_SUPPORTED macro to PNG_TIME_RFC1123_SUPPORTED
    added png_invert_alpha capability (Glenn R-P -- suggestion by Jon Vincent)
    changed srgb_intent from png_byte to int to avoid compiler bugs
+version 0.99 [January 30, 1998]
+   free info_ptr->text instead of end_info_ptr->text in pngread.c (John Bowler)
+   fixed a longstanding "packswap" bug in pngtrans.c
+   fixed some inconsistencies in pngconf.h that prevented compiling with
+      PNG_READ_GAMMA_SUPPORTED and PNG_READ_hIST_SUPPORTED undefined
+   fixed some typos and made other minor rearrangement of libpng.txt (Andreas)
+   changed recommendation about file_gamma for PC images to .50 from .51 in
+      example.c and libpng.txt, and changed file_gamma for sRGB images to .45
+   added a number of functions to access information from the png structure
+      png_get_image_height(), etc. (Glenn R-P, suggestion by Brad Pettit)
+   added TARGET_MACOS similar to zlib-1.0.8
+   define PNG_ALWAYS_EXTERN when __MWERKS__ && WIN32 are defined
+   added type casting to all png_malloc() function calls
+version 0.99a [January 31, 1998]
+   Added type casts and parentheses to all returns that return a value.(Tim W.)
+version 0.99b [February 4, 1998]
+   Added type cast png_uint_32 on malloc function calls where needed.
+   Changed type of num_hist from png_uint_32 to int (same as num_palette).
+   Added checks for rowbytes overflow, in case png_size_t is less than 32 bits.
+   Renamed makefile.elf to makefile.lnx.
+version 0.99c [February 7, 1998]
+   More type casting.  Removed erroneous overflow test in pngmem.c.
+   Added png_buffered_memcpy() and png_buffered_memset(), apply them to rowbytes.
+   Added UNIX manual pages libpng.3 (incorporating libpng.txt) and  png.5.
+version 0.99d [February 11, 1998]
+   Renamed "far_to_near()" "png_far_to_near()"
+   Revised libpng.3
+   Version 99c "buffered" operations didn't work as intended.  Replaced them
+     with png_memcpy_check() and png_memset_check().
+   Added many "if (png_ptr == NULL) return" to quell compiler warnings about
+     unused png_ptr, mostly in pngget.c and pngset.c.
+   Check for overlength tRNS chunk present when indexed-color PLTE is read.
+   Cleaned up spelling errors in libpng.3/libpng.txt
+   Corrected a problem with png_get_tRNS() which returned undefined trans array
+version 0.99e [February 28, 1998]
+   Corrected png_get_tRNS() again.
+   Add parentheses for easier reading of pngget.c, fixed "||" should be "&&".
+   Touched up example.c to make more of it compileable, although the entire
+     file still can't be compiled (Willem van Schaik)
+   Fixed a bug in png_do_shift() (Bryan Tsai)
+   Added a space in png.h prototype for png_write_chunk_start()
+   Replaced pngtest.png with one created with zlib 1.1.1
+   Changed pngtest to report PASS even when file size is different (Jean-loup G.)
+   Corrected some logic errors in png_do_invert_alpha() (Chris Patterson)

README

@@ -1,4 +1,4 @@
-[NOTE:  this is still beta version 0.97d; the text below has already
+[NOTE:  this is still beta version 0.99e; the text below has already
  been updated in anticipation of the imminent 1.0 release.]
 
 
@@ -99,11 +99,11 @@ fix.  Please mention "libpng" somewhere in the subject line.  Thanks.
 This release was created and will be supported by myself (of course
 based in a large way on Guy's and Andreas' earlier work), and the PNG group.
 
-adilger@enel.ucalgary.ca
+randeg@alumni.rpi.edu
 png-implement@dworkin.wustl.edu
 
 You can't reach Guy, the original libpng author, at the addresses
-given in previous versions of this document.  He will read mail
+given in previous versions of this document.  He and Andreas will read mail
 addressed to the png-implement list, however.
 
 Please do not send general questions about PNG.  Send them to
@@ -127,19 +127,22 @@ Files in this distribution:
       CHANGES       =>  Description of changes between libpng versions
       README        =>  This file
       TODO          =>  Things not implemented in the current library
+      ansi2knr.1    =>  Manual page for ansi2knr
       ansi2knr.c    =>  Converts files to K&R style function declarations
       build.bat     =>  MS-DOS batch file for Borland compiler
       descrip.mms   =>  VMS project file
       example.c     =>  Example code for using libpng functions
+      libpng.3      =>  manual page for libpng
       libpng.txt    =>  Description of libpng and its functions
+      libpngpf.3    =>  manual page for libpng's private functions
       makefile.aco  =>  ACORN makefile
       makefile.ama  =>  Amiga makefile
       makefile.atr  =>  Atari makefile
       makefile.bor  =>  Borland makefile
       makefile.dec  =>  DEC makefile
       makefile.dj2  =>  DJGPP 2 makefile
-      makefile.elf  =>  Unix ELF makefile
       makefile.knr  =>  Makefile which calls ansi2knr to convert files
+      makefile.lnx  =>  Unix Linux/ELF makefile
       makefile.mip  =>  MIPS makefile
       makefile.msc  =>  Microsoft C makefile
       makefile.sgi  =>  Silicon Graphics Irix makefile
@@ -147,10 +150,12 @@ Files in this distribution:
       makefile.sun  =>  SUN makefile
       makefile.tc3  =>  Turbo C 3.0 makefile
       makevms.com   =>  VMS make program
+      png.5         =>  manual page for the PNG format
       png.c         =>  Basic interface functions common to library
       png.h         =>  Library function and interface declarations
       pngconf.h     =>  System specific library configuration
       pngerror.c    =>  Error/warning message I/O functions
+      pngget.c      =>  Functions for retrieving info from struct
       pngmem.c      =>  Memory handling functions
       pngpread.c    =>  Progressive reading functions
       pngread.c     =>  Read data/helper high-level functions
@@ -178,5 +183,4 @@ Good luck, and happy coding.
 
 -Guy Eric Schalnat
  (formerly of Group 42, Inc)
- Web: http://www.group42.com/
-
+ Internet: gschal@infinet.com

TODO

@@ -5,7 +5,7 @@ improved dithering
 multi-lingual error and warning message support
 sPLT chunk handling
 cHRM transformation
-complete sRGB transformation (presently it simply uses gamma=0.51)
+complete sRGB transformation (presently it simply uses gamma=0.45)
 man pages for function calls
 high-level API for reading images
 final bug fixes

ansi2knr.1

@@ -0,0 +1,36 @@
+.TH ANSI2KNR 1 "19 Jan 1996"
+.SH NAME
+ansi2knr \- convert ANSI C to Kernighan & Ritchie C
+.SH SYNOPSIS
+.I ansi2knr
+[--varargs] input_file [output_file]
+.SH DESCRIPTION
+If no output_file is supplied, output goes to stdout.
+.br
+There are no error messages.
+.sp
+.I ansi2knr
+recognizes function definitions by seeing a non-keyword identifier at the left
+margin, followed by a left parenthesis, with a right parenthesis as the last
+character on the line, and with a left brace as the first token on the
+following line (ignoring possible intervening comments).  It will recognize a
+multi-line header provided that no intervening line ends with a left or right
+brace or a semicolon.  These algorithms ignore whitespace and comments, except
+that the function name must be the first thing on the line.
+.sp
+The following constructs will confuse it:
+.br
+     - Any other construct that starts at the left margin and follows the
+above syntax (such as a macro or function call).
+.br
+     - Some macros that tinker with the syntax of the function header.
+.sp
+The --varargs switch is obsolete, and is recognized only for
+backwards compatibility.  The present version of
+.I ansi2knr
+will always attempt to convert a ... argument to va_alist and va_dcl.
+.SH AUTHOR
+L. Peter Deutsch <ghost@aladdin.com> wrote the original ansi2knr and
+continues to maintain the current version; most of the code in the current
+version is his work.  ansi2knr also includes contributions by Francois
+Pinard <pinard@iro.umontreal.ca> and Jim Avera <jima@netcom.com>.

example.c

@@ -12,7 +12,7 @@
  * working PNG reader/writer, see pngtest.c, included in this distribution.
  */
 
-#include <png.h>
+#include "png.h"
 
 /* Check to see if a file is a PNG file using png_check_sig().  Returns
  * non-zero if the image is a PNG, and 0 if it isn't a PNG.
@@ -54,7 +54,7 @@ int check_if_png(char *file_name, FILE **fp)
  * file, and the other where we are given an open file (possibly with
  * some or all of the magic bytes read - see comments above).
  */
-**** prototype 1 ****
+#ifdef open_file /* prototype 1 */
 void read_png(char *file_name)  /* We need to open the file */
 {
    png_structp png_ptr;
@@ -66,14 +66,14 @@ void read_png(char *file_name)  /* We need to open the file */
 
    if ((fp = fopen(file_name, "rb")) == NULL)
       return;
-**** prototype 2 ****
+#else no_open_file /* prototype 2 */
 void read_png(FILE *fp, unsigned int sig_read)  /* file is already open */
 {
    png_structp png_ptr;
    png_infop info_ptr;
    png_uint_32 width, height;
    int bit_depth, color_type, interlace_type;
-**** only use one prototype! ****
+#endif no_open_file /* only use one prototype! */
 
    /* Create and initialize the png_struct with the desired error handler
     * functions.  If you want to use the default stderr and longjump method,
@@ -113,17 +113,17 @@ void read_png(FILE *fp, unsigned int sig_read)  /* file is already open */
    }
 
    /* One of the following I/O initialization methods is REQUIRED */
-**** PNG file I/O method 1 ****
+#ifdef streams /* PNG file I/O method 1 */
    /* Set up the input control if you are using standard C streams */
    png_init_io(png_ptr, fp);
 
-**** PNG file I/O method 2 ****
+#else no_streams /* PNG file I/O method 2 */
    /* If you are using replacement read functions, instead of calling
     * png_init_io() here you would call:
     */
    png_set_read_fn(png_ptr, (void *)user_io_ptr, user_read_fn);
    /* where user_io_ptr is a structure you want available to the callbacks */
-**** Use only one I/O method! ****
+#endif no_streams /* Use only one I/O method! */
 
    /* If we have already read some of the signature */
    png_set_sig_bytes_read(png_ptr, sig_read);
@@ -180,10 +180,10 @@ void read_png(FILE *fp, unsigned int sig_read)  /* file is already open */
     * use it - you should use the (solid) application background if it has one.
     */
 
-   png_color_16 my_background, *image_background);
+   png_color_16 my_background, *image_background;
 
-   if (png_get_bKGD(png_ptr, info_ptr, &image_background);
-      png_set_background(png_ptr, image_background),
+   if (png_get_bKGD(png_ptr, info_ptr, &image_background))
+      png_set_background(png_ptr, image_background,
                          PNG_BACKGROUND_GAMMA_FILE, 1, 1.0);
    else
       png_set_background(png_ptr, &my_background,
@@ -191,7 +191,7 @@ void read_png(FILE *fp, unsigned int sig_read)  /* file is already open */
 
    /* Some suggestions as to how to get a screen gamma value */
 
-   /* Note that screen gamma is (display_gamma/viewing_gamma)
+   /* Note that screen gamma is (display_gamma/viewing_gamma) */
    if (/* We have a user-defined screen gamma value */)
    {
       screen_gamma = user-defined screen_gamma;
@@ -204,7 +204,7 @@ void read_png(FILE *fp, unsigned int sig_read)  /* file is already open */
    /* If we don't have another value */
    else
    {
-      screen_gamma = 2.2;  /* A good guess for a PC monitors in a brightly
+      screen_gamma = 2.2;  /* A good guess for a PC monitors in a dimly
                               lit room */
       screen_gamma = 1.7 or 1.0;  /* A good guess for Mac systems */
    }
@@ -217,13 +217,13 @@ void read_png(FILE *fp, unsigned int sig_read)  /* file is already open */
 
    int intent;
 
-   if (png_get_sRGB(png_ptr, info_ptr, &intent)
+   if (png_get_sRGB(png_ptr, info_ptr, &intent))
       png_set_sRGB(png_ptr, intent, 0);
    else 
-      if (png_get_gAMA(png_ptr, info_ptr, &image_gamma)
+      if (png_get_gAMA(png_ptr, info_ptr, &image_gamma))
          png_set_gamma(png_ptr, screen_gamma, image_gamma);
       else
-         png_set_gamma(png_ptr, screen_gamma, 0.51);
+         png_set_gamma(png_ptr, screen_gamma, 0.50);
 
    /* Dither RGB files down to 8 bit palette or reduce palettes
     * to the number of colors available on your screen.
@@ -234,7 +234,7 @@ void read_png(FILE *fp, unsigned int sig_read)  /* file is already open */
       png_colorp palette;
 
       /* This reduces the image to the application supplied palette */
-      if (we have our own palette)
+      if (/* we have our own palette */)
       {
          /* An array of colors to which the image should be dithered */
          png_color std_color_cube[MAX_SCREEN_COLORS];
@@ -243,7 +243,7 @@ void read_png(FILE *fp, unsigned int sig_read)  /* file is already open */
             MAX_SCREEN_COLORS, NULL, 0);
       }
       /* This reduces the image to the palette supplied in the file */
-      else if (png_get_PLTE(png_ptr, info_ptr, &palette, &num_palette)))
+      else if (png_get_PLTE(png_ptr, info_ptr, &palette, &num_palette))
       {
          png_color16p histogram;
 
@@ -255,7 +255,7 @@ void read_png(FILE *fp, unsigned int sig_read)  /* file is already open */
    }
 
    /* invert monocrome files to have 0 as white and 1 as black */
-   png_set_invert(png_ptr);
+   png_set_invert_mono(png_ptr);
 
    /* If you want to shift the pixel values from the range [0,255] or
     * [0,65535] to the original [0,7] or [0,31], or whatever range the
@@ -304,37 +304,37 @@ void read_png(FILE *fp, unsigned int sig_read)  /* file is already open */
    }
 
    /* Now it's time to read the image.  One of these methods is REQUIRED */
-**** Read the entire image in one go ****
+#ifdef entire /* Read the entire image in one go */
    png_read_image(png_ptr, row_pointers);
 
-**** Read the image one or more scanlines at a time ****
+#else no_entire /* Read the image one or more scanlines at a time */
    /* The other way to read images - deal with interlacing: */
 
    for (pass = 0; pass < number_passes; pass++)
    {
-[[[[[[[ Read the image a single row at a time ]]]]]]]
+#ifdef single /* Read the image a single row at a time */
       for (y = 0; y < height; y++)
       {
          png_bytep row_pointers = row[y];
          png_read_rows(png_ptr, &row_pointers, NULL, 1);
       }
 
-[[[[[[[ Read the image several rows at a time ]]]]]]]
+#else no_single /* Read the image several rows at a time */
       for (y = 0; y < height; y += number_of_rows)
       {
-<<<<<<<<<< Read the image using the "sparkle" effect. >>>>>>>>>>
+#ifdef sparkle /* Read the image using the "sparkle" effect. */
          png_read_rows(png_ptr, row_pointers, NULL, number_of_rows);
         
-<<<<<<<<<< Read the image using the "rectangle" effect >>>>>>>>>>
+#else no_sparkle /* Read the image using the "rectangle" effect */
          png_read_rows(png_ptr, NULL, row_pointers, number_of_rows);
-<<<<<<<<<< use only one of these two methods >>>>>>>>>>
+#endif no_sparkle /* use only one of these two methods */
       }
      
       /* if you want to display the image after every pass, do
          so here */
-[[[[[[[ use only one of these two methods ]]]]]]]
+#endif no_single /* use only one of these two methods */
    }
-**** use only one of these two methods ****
+#endif no_entire /* use only one of these two methods */
 
    /* read rest of file, and get additional chunks in info_ptr - REQUIRED */
    png_read_end(png_ptr, info_ptr);
@@ -479,7 +479,7 @@ end_callback(png_structp png_ptr, png_infop info)
 }
 
 /* write a png file */
-void write_png(char *file_name, ... other image information ...)
+void write_png(char *file_name /* , ... other image information ... */)
 {
    FILE *fp;
    png_structp png_ptr;
@@ -526,16 +526,16 @@ void write_png(char *file_name, ... other image information ...)
    }
 
    /* One of the following I/O initialization functions is REQUIRED */
-**** I/O initialization method 1 ****
+#ifdef streams /* I/O initialization method 1 */
    /* set up the output control if you are using standard C streams */
    png_init_io(png_ptr, fp);
-**** I/O initialization method 2 ****
+#else no_streams /* I/O initialization method 2 */
    /* If you are using replacement read functions, instead of calling
     * png_init_io() here you would call */
    png_set_write_fn(png_ptr, (void *)user_io_ptr, user_write_fn,
       user_IO_flush_function);
    /* where user_io_ptr is a structure you want available to the callbacks */
-**** only use 1 initialization method ****
+#endif no_streams /* only use one initialization method */
 
    /* Set the image information here.  Width and height are up to 2^31,
     * bit_depth is one of 1, 2, 4, 8, or 16, but valid values also depend on
@@ -549,8 +549,8 @@ void write_png(char *file_name, ... other image information ...)
       PNG_INTERLACE_????, PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);
 
    /* set the palette if there is one.  REQUIRED for indexed-color images */
-   palette = png_malloc(png_ptr, 256 * sizeof (png_color));
-   ... set palette colors ...
+   palette = (png_colorp)png_malloc(png_ptr, 256 * sizeof (png_color));
+   /* ... set palette colors ... */
    png_set_PLTE(png_ptr, info_ptr, palette, 256);
 
    /* optional significant bit chunk */
@@ -600,7 +600,7 @@ void write_png(char *file_name, ... other image information ...)
     */
 
    /* invert monocrome pixels */
-   png_set_invert(png_ptr);
+   png_set_invert_mono(png_ptr);
 
    /* Shift the pixels up to a legal bit depth and fill in
     * as appropriate to correctly scale the image.
@@ -640,12 +640,12 @@ void write_png(char *file_name, ... other image information ...)
    png_byte row_pointers[height][width];
 
    /* One of the following output methods is REQUIRED */
-**** write out the entire image data in one call ***
+#ifdef entire /* write out the entire image data in one call */
    png_write_image(png_ptr, row_pointers);
 
    /* the other way to write the image - deal with interlacing */
 
-**** write out the image data by one or more scanlines ****
+#else no_entire /* write out the image data by one or more scanlines */
    /* The number of passes is either 1 for non-interlaced images,
     * or 7 for interlaced images.
     */
@@ -661,7 +661,7 @@ void write_png(char *file_name, ... other image information ...)
          png_write_rows(png_ptr, &row_pointers, 1);
       }
    }
-**** use only one output method ****
+#endif no_entire /* use only one output method */
 
    /* You can write optional chunks like tEXt, zTXt, and tIME at the end
     * as well.

libpngpf.3

@@ -0,0 +1,342 @@
+.TH LIBPNGPF 3 "February 28, 1998"
+.SH NAME
+libpng \- Portable Network Graphics (PNG) Reference Library
+(private functions)
+.SH SYNOPSIS
+#include <png.h>
+
+void png_build_gamma_table (png_structp png_ptr);
+
+void png_build_grayscale_palette (int bit_depth, png_colorp
+palette);
+
+void png_calculate_crc (png_structp png_ptr, png_bytep ptr,
+png_size_t length);
+void png_check_chunk_name (png_structp png_ptr, png_bytep
+chunk_name);
+
+png_size_t png_check_keyword (png_structp png_ptr, png_charp
+key, png_charpp new_key);
+
+void png_combine_row (png_structp png_ptr, png_bytep row, int
+mask);
+
+void png_correct_palette (png_structp png_ptr, png_colorp
+palette, int num_palette);
+
+int png_crc_error (png_structp png_ptr);
+
+int png_crc_finish (png_structp png_ptr, png_uint_32 skip);
+
+void png_crc_read (png_structp png_ptr, png_bytep buf,
+png_size_t length);
+
+png_voidp png_create_struct (int type);
+
+void png_destroy_struct (png_voidp struct_ptr);
+
+void png_do_background (png_row_infop row_info, png_bytep row,
+png_color_16p trans_values, png_color_16p background,
+png_color_16p background_1, png_bytep gamma_table, png_bytep
+gamma_from_1, png_bytep gamma_to_1, png_uint_16pp gamma_16,
+png_uint_16pp gamma_16_from_1, png_uint_16pp gamma_16_to_1, int
+gamma_shift);
+
+void png_do_bgr (png_row_infop row_info, png_bytep row);
+
+void png_do_chop (png_row_infop row_info, png_bytep row);
+
+void png_do_dither (png_row_infop row_info, png_bytep row,
+png_bytep palette_lookup, png_bytep dither_lookup);
+
+void png_do_expand (png_row_infop row_info, png_bytep row,
+png_color_16p trans_value);
+
+void png_do_expand_palette (png_row_infop row_info, png_bytep
+row, png_colorp palette, png_bytep trans, int num_trans);
+
+void png_do_gamma (png_row_infop row_info, png_bytep row,
+png_bytep gamma_table, png_uint_16pp gamma_16_table, int
+gamma_shift);
+
+void png_do_gray_to_rgb (png_row_infop row_info, png_bytep
+row);
+
+void png_do_invert (png_row_infop row_info, png_bytep row);
+
+void png_do_pack (png_row_infop row_info, png_bytep row,
+png_uint_32 bit_depth);
+
+void png_do_packswap (png_row_infop row_info, png_bytep row);
+
+void png_do_read_filler (png_row_infop row_info, png_bytep row,
+png_uint_32 filler, png_uint_32 flags);
+
+void png_do_read_interlace (png_row_infop row_info, png_bytep
+row, int pass, png_uint_32 transformations);
+
+void png_do_read_invert_alpha (png_row_infop row_info,
+png_bytep row);
+
+void png_do_read_swap_alpha (png_row_infop row_info, png_bytep
+row);
+
+void png_do_read_transformations (png_structp png_ptr);
+
+void png_do_rgb_to_gray (png_row_infop row_info, png_bytep
+row);
+
+void png_do_shift (png_row_infop row_info, png_bytep row,
+png_color_8p bit_depth);
+
+void png_do_strip_filler (png_row_infop row_info, png_bytep
+row, png_uint_32 flags);
+
+void png_do_swap (png_row_infop row_info, png_bytep row);
+
+void png_do_unpack (png_row_infop row_info, png_bytep row);
+
+void png_do_unshift (png_row_infop row_info, png_bytep row,
+png_color_8p sig_bits);
+
+void png_do_write_interlace (png_row_infop row_info, png_bytep
+row, int pass);
+
+void png_do_write_invert_alpha (png_row_infop row_info,
+png_bytep row);
+
+void png_do_write_swap_alpha (png_row_infop row_info, png_bytep
+row);
+
+void png_do_write_transformations (png_structp png_ptr);
+
+void *png_far_to_near (png_structp png_ptr,png_voidp ptr,
+int check);
+
+void png_flush (png_structp png_ptr);
+
+png_int_32 png_get_int_32 (png_bytep buf);
+
+png_uint_16 png_get_uint_16 (png_bytep buf);
+
+png_uint_32 png_get_uint_32 (png_bytep buf);
+
+void png_handle_bKGD (png_structp png_ptr, png_infop info_ptr,
+png_uint_32 length);
+
+void png_handle_cHRM (png_structp png_ptr, png_infop info_ptr,
+png_uint_32 length);
+
+void png_handle_gAMA (png_structp png_ptr, png_infop info_ptr,
+png_uint_32 length);
+
+void png_handle_hIST (png_structp png_ptr, png_infop info_ptr,
+png_uint_32 length);
+
+void png_handle_IEND (png_structp png_ptr, png_infop info_ptr,
+png_uint_32 length);
+
+void png_handle_IHDR (png_structp png_ptr, png_infop info_ptr,
+png_uint_32 length);
+
+void png_handle_oFFs (png_structp png_ptr, png_infop info_ptr,
+png_uint_32 length);
+
+void png_handle_pCAL (png_structp png_ptr, png_infop info_ptr,
+png_uint_32 length);
+
+void png_handle_pHYs (png_structp png_ptr, png_infop info_ptr,
+png_uint_32 length);
+
+void png_handle_PLTE (png_structp png_ptr, png_infop info_ptr,
+png_uint_32 length);
+
+void png_handle_sBIT (png_structp png_ptr, png_infop info_ptr,
+png_uint_32 length);
+
+void png_handle_sRGB (png_structp png_ptr, png_infop info_ptr,
+png_uint_32 length);
+
+void png_handle_tEXt (png_structp png_ptr, png_infop info_ptr,
+png_uint_32 length);
+
+void png_handle_tIME (png_structp png_ptr, png_infop info_ptr,
+png_uint_32 length);
+
+void png_handle_tRNS (png_structp png_ptr, png_infop info_ptr,
+png_uint_32 length);
+
+void png_handle_unknown (png_structp png_ptr, png_infop
+info_ptr, png_uint_32 length);
+
+void png_handle_zTXt (png_structp png_ptr, png_infop info_ptr,
+png_uint_32 length);
+
+void png_info_destroy (png_structp png_ptr, png_infop
+info_ptr);
+
+void png_init_read_transformations (png_structp png_ptr);
+
+void png_process_IDAT_data (png_structp png_ptr, png_bytep
+buffer, png_size_t buffer_length);
+
+void png_process_some_data (png_structp png_ptr, png_infop
+info_ptr);
+
+void png_push_check_crc (png_structp png_ptr);
+
+void png_push_crc_finish (png_structp png_ptr);
+
+void png_push_crc_skip (png_structp png_ptr, png_uint_32
+length);
+
+void png_push_fill_buffer (png_structp png_ptr, png_bytep
+buffer, png_size_t length);
+
+void png_push_handle_tEXt (png_structp png_ptr, png_infop
+info_ptr, png_uint_32 length);
+
+void png_push_handle_unknown (png_structp png_ptr, png_infop
+info_ptr, png_uint_32 length);
+
+void png_push_handle_zTXt (png_structp png_ptr, png_infop
+info_ptr, png_uint_32 length);
+
+void png_push_have_end (png_structp png_ptr, png_infop
+info_ptr);
+
+void png_push_have_info (png_structp png_ptr, png_infop
+info_ptr);
+
+void png_push_have_row (png_structp png_ptr, png_bytep row);
+
+void png_push_process_row (png_structp png_ptr);
+
+void png_push_read_chunk (png_structp png_ptr, png_infop
+info_ptr);
+
+void png_push_read_end (png_structp png_ptr, png_infop
+info_ptr);
+
+void png_push_read_IDAT (png_structp png_ptr);
+
+void png_push_read_sig (png_structp png_ptr, png_infop
+info_ptr);
+
+void png_push_read_tEXt (png_structp png_ptr, png_infop
+info_ptr);
+
+void png_push_read_zTXt (png_structp png_ptr, png_infop
+info_ptr);
+
+void png_push_restore_buffer (png_structp png_ptr, png_bytep
+buffer, png_size_t buffer_length);
+
+void png_push_save_buffer (png_structp png_ptr);
+
+void png_read_data (png_structp png_ptr, png_bytep data,
+png_size_t length);
+
+void png_read_filter_row (png_structp png_ptr, png_row_infop
+row_info, png_bytep row, png_bytep prev_row, int filter);
+
+void png_read_finish_row (png_structp png_ptr);
+
+void png_read_init (png_structp png_ptr);
+
+void png_read_push_finish_row (png_structp png_ptr);
+
+void png_read_start_row (png_structp png_ptr);
+
+void png_read_transform_info (png_structp png_ptr, png_infop
+info_ptr);
+
+void png_reset_crc (png_structp png_ptr);
+
+void png_save_int_32 (png_bytep buf, png_int_32 i);
+
+void png_save_uint_16 (png_bytep buf, unsigned int i);
+
+void png_save_uint_32 (png_bytep buf, png_uint_32 i);
+
+void png_write_bKGD (png_structp png_ptr, png_color_16p values,
+int color_type);
+
+void png_write_cHRM (png_structp png_ptr, double white_x,
+double white_y, double red_x, double red_y, double green_x,
+double green_y, double blue_x, double blue_y);
+
+void png_write_data (png_structp png_ptr, png_bytep data,
+png_size_t length);
+void png_write_filtered_row (png_structp png_ptr, png_bytep
+filtered_row);
+
+void png_write_find_filter (png_structp png_ptr, png_row_infop
+row_info);
+
+void png_write_finish_row (png_structp png_ptr);
+
+void png_write_gAMA (png_structp png_ptr, double file_gamma);
+
+void png_write_hIST (png_structp png_ptr, png_uint_16p hist,
+int num_hist);
+
+void png_write_init (png_structp png_ptr);
+
+void png_write_IDAT (png_structp png_ptr, png_bytep data,
+png_size_t length);
+
+void png_write_IEND (png_structp png_ptr);
+
+void png_write_IHDR (png_structp png_ptr, png_uint_32 width,
+png_uint_32 height, int bit_depth, int color_type, int
+compression_type, int filter_type, int interlace_type);
+
+void png_write_oFFs (png_structp png_ptr, png_uint_32 x_offset,
+png_uint_32 y_offset, int unit_type);
+
+void png_write_pCAL (png_structp png_ptr, png_charp purpose,
+png_int_32 X0, png_int_32 X1, int type, int nparams, png_charp
+units, png_charpp params);
+
+void png_write_pHYs (png_structp png_ptr, png_uint_32
+x_pixels_per_unit, png_uint_32 y_pixels_per_unit, int
+unit_type);
+
+void png_write_PLTE (png_structp png_ptr, png_colorp palette,
+png_uint_32 num_pal);
+
+void png_write_sBIT (png_structp png_ptr, png_color_8p sbit,
+int color_type);
+
+void png_write_sig (png_structp png_ptr);
+
+void png_write_sRGB (png_structp png_ptr, int intent);
+
+void png_write_start_row (png_structp png_ptr);
+
+void png_write_tEXt (png_structp png_ptr, png_charp key,
+png_charp text, png_size_t text_len);
+
+void png_write_tIME (png_structp png_ptr, png_timep mod_time);
+
+void png_write_tRNS (png_structp png_ptr, png_bytep trans,
+png_color_16p values, int number, int color_type);
+
+void png_write_zTXt (png_structp png_ptr, png_charp key,
+png_charp text, png_size_t text_len, int compression);
+
+voidpf png_zalloc (voidpf png_ptr, uInt items, uInt size);
+
+void png_zfree (voidpf png_ptr, voidpf ptr);
+
+.SH DESCRIPTION
+The functions listed above are used privately by libpng
+and are not recommended for use by applications.  They
+are listed alphabetically here as an aid to libpng maintainers.
+See png.h for more information on these functions.
+
+.SH SEE ALSO
+libpng(3), png(5)
+.SH AUTHOR
+Glenn Randers-Pehrson

makefile.lnx

@@ -22,7 +22,7 @@ RANLIB=ranlib
 #RANLIB=echo
 
 PNGMAJ = 2
-PNGMIN = 0.98
+PNGMIN = 0.99
 PNGVER = $(PNGMAJ).$(PNGMIN)
 
 # where make install puts libpng.a, libpng.so*, and png.h

makefile.msc

@@ -5,7 +5,7 @@
 
 # ------------- Microsoft C 5.1 and later -------------
 MODEL=-AL
-CFLAGS=-Oait -Gs -nologo -W2 $(MODEL) -I..\zlib
+CFLAGS=-Oait -Gs -nologo -W3 $(MODEL) -I..\zlib
 #-Ox generates bad code with MSC 5.1
 CC=cl
 LD=link

png.5

@@ -0,0 +1,44 @@
+.TH PNG 5 "February 28, 1998"
+.SH NAME
+png \- Portable Network Graphics (PNG) format
+.SH DESCRIPTION
+PNG (Portable Network Graphics) is an extensible file format for the
+lossless, portable, well-compressed storage of raster images. PNG provides
+a patent-free replacement for GIF and can also replace many
+common uses of TIFF. Indexed-color, grayscale, and truecolor images are
+supported, plus an optional alpha channel. Sample depths range from
+1 to 16 bits. 
+.br
+
+PNG is designed to work well in online viewing applications, such as the
+World Wide Web, so it is fully streamable with a progressive display
+option. PNG is robust, providing both full file integrity checking and
+fast, simple detection of common transmission errors. Also, PNG can store
+gamma and chromaticity data for improved color matching on heterogeneous
+platforms. 
+
+.SH "SEE ALSO"
+.IR libpng(3), zlib(3), deflate(5), and zlib(5)
+.LP
+PNG specification:
+RFC 2083
+.IP
+.br
+ftp://ds.internic.net/rfc/rfc2083.txt
+.br
+or (as a W3C Recommendation) at
+.br
+http://www.w3.org/TR/REC-png.html
+.SH AUTHORS
+This man page: Glenn Randers-Pehrson
+.LP
+Portable Network Graphics (PNG) Specification Version 1.0 (October 1, 1996):
+Thomas Boutell and others (png-list@dworkin.wustl.edu).
+.LP
+
+.SH COPYRIGHT NOTICE
+The PNG specification is copyright (c) 1996 Massachussets Institute of
+Technology.  See the specification for conditions of use and distribution.
+.LP
+.\" end of man page
+

png.c

@@ -1,12 +1,12 @@
 
 /* png.c - location for general purpose libpng functions
  *
- * libpng 0.98
+ * libpng 0.99e
  * For conditions of distribution and use, see copyright notice in png.h
  * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
  * Copyright (c) 1996, 1997 Andreas Dilger
  * Copyright (c) 1998, Glenn Randers-Pehrson
- * January 16, 1998
+ * February 28, 1998
  */
 
 #define PNG_INTERNAL
@@ -16,9 +16,9 @@
 /* Version information for C files.  This had better match the version
  * string defined in png.h.
  */
-char png_libpng_ver[] = "0.98";
+char png_libpng_ver[5] = "0.99";
 
-/* Place to hold the signiture string for a PNG file. */
+/* Place to hold the signature string for a PNG file. */
 png_byte FARDATA png_sig[8] = {137, 80, 78, 71, 13, 10, 26, 10};
 
 /* Constant strings for known chunk types.  If you need to add a chunk,
@@ -103,15 +103,15 @@ png_sig_cmp(png_bytep sig, png_size_t start, png_size_t num_to_check)
    if (num_to_check > 8)
       num_to_check = 8;
    else if (num_to_check < 1)
-      return 0;
+      return (0);
 
    if (start > 7)
-      return 0;
+      return (0);
 
    if (start + num_to_check > 8)
       num_to_check = 8 - start;
 
-   return (png_memcmp(&sig[start], &png_sig[start], num_to_check));
+   return ((int)(png_memcmp(&sig[start], &png_sig[start], num_to_check)));
 }
 
 /* (Obsolete) function to check signature bytes.  It does not allow one
@@ -121,7 +121,7 @@ png_sig_cmp(png_bytep sig, png_size_t start, png_size_t num_to_check)
 int
 png_check_sig(png_bytep sig, int num)
 {
-  return !png_sig_cmp(sig, (png_size_t)0, (png_size_t)num);
+  return ((int)!png_sig_cmp(sig, (png_size_t)0, (png_size_t)num));
 }
 
 /* Function to allocate memory for zlib. */
@@ -132,7 +132,7 @@ png_zalloc(voidpf png_ptr, uInt items, uInt size)
    png_uint_32 num_bytes;
 
    num_bytes = (png_uint_32)items * size;
-   ptr = png_malloc((png_structp)png_ptr, num_bytes);
+   ptr = (png_voidp)png_malloc((png_structp)png_ptr, num_bytes);
    if (num_bytes > (png_uint_32)0x8000)
    {
       png_memset(ptr, 0, (png_size_t)0x8000L);
@@ -143,7 +143,7 @@ png_zalloc(voidpf png_ptr, uInt items, uInt size)
    {
       png_memset(ptr, 0, (png_size_t)num_bytes);
    }
-   return (voidpf)(ptr);
+   return ((voidpf)ptr);
 }
 
 /* function to free memory for zlib */
@@ -200,12 +200,13 @@ png_create_info_struct(png_structp png_ptr)
    png_infop info_ptr;
 
    png_debug(1, "in png_create_info_struct\n");
+   if(png_ptr == NULL) return (NULL);
    if ((info_ptr = (png_infop)png_create_struct(PNG_STRUCT_INFO)) != NULL)
    {
       png_info_init(info_ptr);
    }
 
-   return info_ptr;
+   return (info_ptr);
 }
 
 /* This function frees the memory associated with a single info struct.
@@ -268,7 +269,7 @@ png_info_destroy(png_structp png_ptr, png_infop info_ptr)
    png_free(png_ptr, info_ptr->pcal_units);
    if (info_ptr->pcal_params != NULL)
    {
-      for (i = 0; i < info_ptr->pcal_nparams; i++)
+      for (i = 0; i < (int)info_ptr->pcal_nparams; i++)
       {
          png_free(png_ptr, info_ptr->pcal_params[i]);
       }
@@ -286,7 +287,7 @@ png_info_destroy(png_structp png_ptr, png_infop info_ptr)
 png_voidp
 png_get_io_ptr(png_structp png_ptr)
 {
-   return png_ptr->io_ptr;
+   return (png_ptr->io_ptr);
 }
 
 #if !defined(PNG_NO_STDIO)

png.h

@@ -1,12 +1,12 @@
 
 /* png.h - header file for PNG reference library
  *
- * libpng 0.98 beta
- * For conditions of distribution and use, see copyright notice in png.h
+ * libpng 0.99e beta
+ * For conditions of distribution and use, see the COPYRIGHT NOTICE below.
  * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
  * Copyright (c) 1996, 1997 Andreas Dilger
  * Copyright (c) 1998 Glenn Randers-Pehrson
- * January 16, 1998
+ * February 28, 1998
  *
  * Note about libpng version numbers:
  *
@@ -27,6 +27,10 @@
  *      0.97c                     0.97      2.0.97
  *      0.98                      0.98      2.0.98
  *      0.99                      0.99      2.0.99
+ *      0.99a                     0.99      2.0.99
+ *      0.99b                     0.99      2.0.99
+ *      0.99c                     0.99      2.0.99
+ *      0.99e                     0.99      2.0.99
  *      1.0                       1.00      2.1.0
  *
  *    Henceforth the source version will match the shared-library minor
@@ -46,12 +50,12 @@
  *
  * See libpng.txt for more information.  The PNG specification is available
  * as RFC 2083 <ftp://ftp.uu.net/graphics/png/documents/>
- * and as a W3C Recommendation <http://www.w3.org/pub/WWW/TR/REC.png.html>
+ * and as a W3C Recommendation <http://www.w3.org/TR/REC.png.html>
  *
  * Contributing Authors:
  *    John Bowler
- *    Sam Bushell
  *    Kevin Bracey
+ *    Sam Bushell
  *    Andreas Dilger
  *    Magnus Holmgren
  *    Tom Lane
@@ -61,6 +65,7 @@
  *    Guy Eric Schalnat
  *    Paul Schmidt
  *    Tom Tanner
+ *    Willem van Schaik
  *    Tim Wegner
  *
  * The contributing authors would like to thank all those who helped
@@ -69,6 +74,8 @@
  *
  * Thanks to Frank J. T. Wojcik for helping with the documentation.
  *
+ * COPYRIGHT NOTICE:
+ *
  * The PNG Reference Library is supplied "AS IS".  The Contributing Authors
  * and Group 42, Inc. disclaim all warranties, expressed or implied,
  * including, without limitation, the warranties of merchantability and of
@@ -119,30 +126,30 @@ extern "C" {
  */
 
 /* Version information for png.h - this should match the version in png.c */
-#define PNG_LIBPNG_VER_STRING "0.98"
+#define PNG_LIBPNG_VER_STRING "0.99"
 
 /* careful here.  At one time, I wanted to use 082, but that would be octal.
  * Version 1.0 will be 100 here, etc.
  */
-#define PNG_LIBPNG_VER  98
+#define PNG_LIBPNG_VER  99
 
 /* variables declared in png.c - only it needs to define PNG_NO_EXTERN */
-#ifndef PNG_NO_EXTERN
+#if !defined(PNG_NO_EXTERN) || defined(PNG_ALWAYS_EXTERN)
 /* Version information for C files, stored in png.c.  This had better match
  * the version above.
  */
-extern char png_libpng_ver[];
+extern char png_libpng_ver[5];
 
 /* Structures to facilitate easy interlacing.  See png.c for more details */
-extern int FARDATA png_pass_start[];
-extern int FARDATA png_pass_inc[];
-extern int FARDATA png_pass_ystart[];
-extern int FARDATA png_pass_yinc[];
-extern int FARDATA png_pass_mask[];
-extern int FARDATA png_pass_dsp_mask[];
+extern int FARDATA png_pass_start[7];
+extern int FARDATA png_pass_inc[7];
+extern int FARDATA png_pass_ystart[7];
+extern int FARDATA png_pass_yinc[7];
+extern int FARDATA png_pass_mask[7];
+extern int FARDATA png_pass_dsp_mask[7];
 /* These aren't currently used.  If you need them, see png.c for more details
-extern int FARDATA png_pass_width[];
-extern int FARDATA png_pass_height[];
+extern int FARDATA png_pass_width[7];
+extern int FARDATA png_pass_height[7];
 */
 #endif /* PNG_NO_EXTERN */
 
@@ -246,7 +253,7 @@ typedef struct png_info_struct
    png_uint_32 width;       /* width of image in pixels (from IHDR) */
    png_uint_32 height;      /* height of image in pixels (from IHDR) */
    png_uint_32 valid;       /* valid chunk data (see PNG_INFO_ below) */
-   png_size_t rowbytes;     /* bytes needed to hold an untransformed row */
+   png_uint_32 rowbytes;    /* bytes needed to hold an untransformed row */
    png_colorp palette;      /* array of color values (valid & PNG_INFO_PLTE) */
    png_uint_16 num_palette; /* number of color entries in "palette" (PLTE) */
    png_uint_16 num_trans;   /* number of transparent palette color (tRNS) */
@@ -268,7 +275,8 @@ typedef struct png_info_struct
     * and initialize the appropriate fields below.
     */
 
-#if defined(PNG_READ_gAMA_SUPPORTED) || defined(PNG_WRITE_gAMA_SUPPORTED)
+#if defined(PNG_READ_gAMA_SUPPORTED) || defined(PNG_WRITE_gAMA_SUPPORTED) || \
+    defined(PNG_READ_GAMMA_SUPPORTED)
    /* The gAMA chunk describes the gamma characteristics of the system
     * on which the image was created, normally in the range [1.0, 2.5].
     * Data is valid if (valid & PNG_INFO_gAMA) is non-zero.
@@ -323,7 +331,8 @@ typedef struct png_info_struct
    png_bytep trans; /* transparent values for paletted image */
    png_color_16 trans_values; /* transparent color for non-palette image */
 #endif /* PNG_READ_tRNS_SUPPORTED || PNG_WRITE_tRNS_SUPPORTED */
-#if defined(PNG_READ_bKGD_SUPPORTED) || defined(PNG_WRITE_bKGD_SUPPORTED)
+#if defined(PNG_READ_bKGD_SUPPORTED) || defined(PNG_WRITE_bKGD_SUPPORTED) || \
+    defined(PNG_READ_BACKGROUND_SUPPORTED)
    /* The bKGD chunk gives the suggested image background color if the
     * display program does not have its own background color and the image
     * is needs to composited onto a background before display.  The colors
@@ -444,6 +453,15 @@ typedef png_info FAR * FAR * png_infopp;
 #define PNG_RESOLUTION_METER      1 /* pixels/meter */
 #define PNG_RESOLUTION_LAST       2 /* Not a valid value */
 
+/* These are for the sRGB chunk.  These values should NOT be changed. */
+#define PNG_sRGB_INTENT_SATURATION 0
+#define PNG_sRGB_INTENT_PERCEPTUAL 1
+#define PNG_sRGB_INTENT_ABSOLUTE   2
+#define PNG_sRGB_INTENT_RELATIVE   3
+#define PNG_sRGB_INTENT_LAST       4 /* Not a valid value */
+                        
+
+
 /* These determine if an ancillary chunk's data has been successfully read
  * from the PNG header, or if the application has filled in the corresponding
  * data in the info_struct to be written into the output file.  The values
@@ -469,7 +487,7 @@ typedef png_info FAR * FAR * png_infopp;
 typedef struct png_row_info_struct
 {
    png_uint_32 width; /* width of row */
-   png_size_t rowbytes; /* number of bytes in row */
+   png_uint_32 rowbytes; /* number of bytes in row */
    png_byte color_type; /* color type of row */
    png_byte bit_depth; /* bit depth of row */
    png_byte channels; /* number of channels (1, 2, 3, or 4) */
@@ -532,8 +550,8 @@ struct png_struct_def
    png_uint_32 height;        /* height of image in pixels */
    png_uint_32 num_rows;      /* number of rows in current pass */
    png_uint_32 usr_width;     /* width of row at start of write */
-   png_size_t rowbytes;       /* size of row in bytes */
-   png_size_t irowbytes;      /* size of current interlaced row in bytes */
+   png_uint_32 rowbytes;      /* size of row in bytes */
+   png_uint_32 irowbytes;     /* size of current interlaced row in bytes */
    png_uint_32 iwidth;        /* width of current interlaced row in pixels */
    png_uint_32 row_number;    /* current row in interlace pass */
    png_bytep prev_row;        /* buffer to save previous (unfiltered) row */
@@ -636,8 +654,10 @@ struct png_struct_def
 #if defined(PNG_READ_DITHER_SUPPORTED)
    png_bytep palette_lookup;         /* lookup table for dithering */
    png_bytep dither_index;           /* index translation for palette files */
-   png_uint_16p hist;                /* histogram */
 #endif /* PNG_READ_DITHER_SUPPORTED */
+#if defined(PNG_READ_DITHER_SUPPORTED) || defined(PNG_READ_hIST_SUPPORTED)
+   png_uint_16p hist;                /* histogram */
+#endif
 #if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
    png_byte heuristic_method;        /* heuristic for row filter selection */
    png_byte num_prev_filters;        /* number of weights for previous rows */
@@ -689,6 +709,21 @@ extern PNG_EXPORT(png_structp,png_create_write_struct)
    PNGARG((png_const_charp user_png_ver, voidp error_ptr,
    png_error_ptr error_fn, png_error_ptr warn_fn));
 
+/* Write a PNG chunk - size, type, (optional) data, CRC. */
+extern PNG_EXPORT(void,png_write_chunk) PNGARG((png_structp png_ptr,
+   png_bytep chunk_name, png_bytep data, png_size_t length));
+
+/* Write the start of a PNG chunk - length and chunk name. */
+extern PNG_EXPORT(void,png_write_chunk_start) PNGARG((png_structp png_ptr,
+   png_bytep chunk_name, png_uint_32 length));
+
+/* Write the data of a PNG chunk started with png_write_chunk_start(). */
+extern PNG_EXPORT(void,png_write_chunk_data) PNGARG((png_structp png_ptr,
+   png_bytep data, png_size_t length));
+
+/* Finish a chunk started with png_write_chunk_start() (includes CRC). */
+extern PNG_EXPORT(void,png_write_chunk_end) PNGARG((png_structp png_ptr));
+
 /* Allocate and initialize the info structure */
 extern PNG_EXPORT(png_infop,png_create_info_struct)
    PNGARG((png_structp png_ptr));
@@ -1091,8 +1126,22 @@ extern PNG_EXPORT(png_voidp,png_malloc) PNGARG((png_structp png_ptr,
 /* frees a pointer allocated by png_malloc() */
 extern PNG_EXPORT(void,png_free) PNGARG((png_structp png_ptr, png_voidp ptr));
 
+extern PNG_EXPORT(png_voidp,png_memcpy_check) PNGARG((png_structp png_ptr,
+   png_voidp s1, png_voidp s2, png_uint_32 size));
+
+extern PNG_EXPORT(png_voidp,png_memset_check) PNGARG((png_structp png_ptr,
+   png_voidp s1, int value, png_uint_32 size));
+
+#ifdef PNGTEST_MEMORY_DEBUG
+/* debugging versions of png_malloc() and png_free() */
+extern PNG_EXPORT(png_voidp,png_debug_malloc) PNGARG((png_structp png_ptr,
+   png_uint_32 size));
+extern PNG_EXPORT(void,png_debug_free) PNGARG((png_structp png_ptr,
+   png_voidp ptr));
+#endif
 #if defined(USE_FAR_KEYWORD)  /* memory model conversion function */
-extern void *far_to_near PNGARG((png_structp png_ptr,png_voidp ptr,int check));
+extern void *png_far_to_near PNGARG((png_structp png_ptr,png_voidp ptr,
+   int check));
 #endif /* USE_FAR_KEYWORD */
 
 /* Fatal error in PNG image of libpng - can't continue */
@@ -1123,18 +1172,71 @@ extern PNG_EXPORT(void,png_chunk_warning) PNGARG((png_structp png_ptr,
  * to avoid problems with future changes in the size and internal layout of
  * png_info_struct.
  */
-/* Returns "flag" if chunk data is valid in info_ptr */
+/* Returns "flag" if chunk data is valid in info_ptr. */
 extern PNG_EXPORT(png_uint_32,png_get_valid) PNGARG((png_structp png_ptr,
 png_infop info_ptr, png_uint_32 flag));
 
-/* Returns number of bytes needed to hold a transformed row */
+/* Returns number of bytes needed to hold a transformed row. */
 extern PNG_EXPORT(png_uint_32,png_get_rowbytes) PNGARG((png_structp png_ptr,
 png_infop info_ptr));
 
-/* Returns number of color channels in image */
+/* Returns number of color channels in image. */
 extern PNG_EXPORT(png_byte,png_get_channels) PNGARG((png_structp png_ptr,
 png_infop info_ptr));
 
+#ifdef PNG_EASY_ACCESS_SUPPORTED
+/* Returns image width in pixels. */
+extern PNG_EXPORT(png_uint_32, png_get_image_width) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+
+/* Returns image height in pixels. */
+extern PNG_EXPORT(png_uint_32, png_get_image_height) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+
+/* Returns image bit_depth. */
+extern PNG_EXPORT(png_byte, png_get_bit_depth) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+
+/* Returns image color_type. */
+extern PNG_EXPORT(png_byte, png_get_color_type) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+
+/* Returns image filter_type. */
+extern PNG_EXPORT(png_byte, png_get_filter_type) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+
+/* Returns image interlace_type. */
+extern PNG_EXPORT(png_byte, png_get_interlace_type) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+
+/* Returns image compression_type. */
+extern PNG_EXPORT(png_byte, png_get_compression_type) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+
+/* Returns image resolution in pixels per meter, from pHYs chunk data. */
+extern PNG_EXPORT(png_uint_32, png_get_pixels_per_meter) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+extern PNG_EXPORT(png_uint_32, png_get_x_pixels_per_meter) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+extern PNG_EXPORT(png_uint_32, png_get_y_pixels_per_meter) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+
+/* Returns pixel aspect ratio, computed from pHYs chunk data.  */
+extern PNG_EXPORT(float, png_get_pixel_aspect_ratio) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+
+/* Returns image x, y offset in pixels or microns, from oFFs chunk data. */
+extern PNG_EXPORT(png_uint_32, png_get_x_offset_pixels) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+extern PNG_EXPORT(png_uint_32, png_get_y_offset_pixels) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+extern PNG_EXPORT(png_uint_32, png_get_x_offset_microns) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+extern PNG_EXPORT(png_uint_32, png_get_y_offset_microns) PNGARG((png_structp
+png_ptr, png_infop info_ptr));
+
+#endif /* PNG_EASY_ACCESS_SUPPORTED */
+
 /* Returns pointer to signature string read from PNG header */
 extern PNG_EXPORT(png_bytep,png_get_signature) PNGARG((png_structp png_ptr,
 png_infop info_ptr));
@@ -1294,6 +1396,9 @@ extern PNG_EXPORT(void,png_set_tRNS) PNGARG((png_structp png_ptr,
  * libpng yet, but more support will be added as needed.
  */
 #if (PNG_DEBUG > 0)
+#ifdef PNG_NO_STDIO
+#include <stdio.h>
+#endif
 #ifndef PNG_DEBUG_FILE
 #define PNG_DEBUG_FILE stderr
 #endif /* PNG_DEBUG_FILE */
@@ -1361,10 +1466,10 @@ extern PNG_EXPORT(void,png_set_tRNS) PNGARG((png_structp png_ptr,
 #define PNG_GAMMA              0x2000
 #define PNG_GRAY_TO_RGB        0x4000
 #define PNG_FILLER             0x8000
-#define PNG_PACKSWAP          0x10000
-#define PNG_SWAP_ALPHA        0x20000
-#define PNG_STRIP_ALPHA       0x40000
-#define PNG_INVERT_ALPHA      0x80000
+#define PNG_PACKSWAP          0x10000L
+#define PNG_SWAP_ALPHA        0x20000L
+#define PNG_STRIP_ALPHA       0x40000L
+#define PNG_INVERT_ALPHA      0x80000L
 
 /* flags for png_create_struct */
 #define PNG_STRUCT_PNG   0x0001
@@ -1392,8 +1497,8 @@ extern PNG_EXPORT(void,png_set_tRNS) PNGARG((png_structp png_ptr,
 #define PNG_FLAG_FREE_PALETTE             0x1000
 #define PNG_FLAG_FREE_TRANS               0x2000
 #define PNG_FLAG_FREE_HIST                0x4000
-#define PNG_FLAG_HAVE_CHUNK_HEADER        0x8000
-#define PNG_FLAG_WROTE_tIME              0x10000
+#define PNG_FLAG_HAVE_CHUNK_HEADER        0x8000L
+#define PNG_FLAG_WROTE_tIME              0x10000L
 
 #define PNG_FLAG_CRC_ANCILLARY_MASK (PNG_FLAG_CRC_ANCILLARY_USE | \
                                      PNG_FLAG_CRC_ANCILLARY_NOWARN)
@@ -1410,32 +1515,32 @@ extern PNG_EXPORT(void,png_set_tRNS) PNGARG((png_structp png_ptr,
    abs((int)((c1).blue) - (int)((c2).blue)))
 
 /* variables declared in png.c - only it needs to define PNG_NO_EXTERN */
-#ifndef PNG_NO_EXTERN
-/* place to hold the signiture string for a PNG file. */
-extern png_byte FARDATA png_sig[];
+#if !defined(PNG_NO_EXTERN) || defined(PNG_ALWAYS_EXTERN)
+/* place to hold the signature string for a PNG file. */
+extern png_byte FARDATA png_sig[8];
 
 /* Constant strings for known chunk types.  If you need to add a chunk,
  * add a string holding the name here.  See png.c for more details.  We
  * can't selectively include these, since we still check for chunk in the
  * wrong locations with these labels.
  */
-extern png_byte FARDATA png_IHDR[];
-extern png_byte FARDATA png_IDAT[];
-extern png_byte FARDATA png_IEND[];
-extern png_byte FARDATA png_PLTE[];
-extern png_byte FARDATA png_bKGD[];
-extern png_byte FARDATA png_cHRM[];
-extern png_byte FARDATA png_gAMA[];
-extern png_byte FARDATA png_hIST[];
-extern png_byte FARDATA png_oFFs[];
-extern png_byte FARDATA png_pCAL[];
-extern png_byte FARDATA png_pHYs[];
-extern png_byte FARDATA png_sBIT[];
-extern png_byte FARDATA png_sRGB[];
-extern png_byte FARDATA png_tEXt[];
-extern png_byte FARDATA png_tIME[];
-extern png_byte FARDATA png_tRNS[];
-extern png_byte FARDATA png_zTXt[];
+extern png_byte FARDATA png_IHDR[5];
+extern png_byte FARDATA png_IDAT[5];
+extern png_byte FARDATA png_IEND[5];
+extern png_byte FARDATA png_PLTE[5];
+extern png_byte FARDATA png_bKGD[5];
+extern png_byte FARDATA png_cHRM[5];
+extern png_byte FARDATA png_gAMA[5];
+extern png_byte FARDATA png_hIST[5];
+extern png_byte FARDATA png_oFFs[5];
+extern png_byte FARDATA png_pCAL[5];
+extern png_byte FARDATA png_pHYs[5];
+extern png_byte FARDATA png_sBIT[5];
+extern png_byte FARDATA png_sRGB[5];
+extern png_byte FARDATA png_tEXt[5];
+extern png_byte FARDATA png_tIME[5];
+extern png_byte FARDATA png_tRNS[5];
+extern png_byte FARDATA png_zTXt[5];
 
 #endif /* PNG_NO_EXTERN */
 
@@ -1535,22 +1640,7 @@ PNG_EXTERN void png_save_int_32 PNGARG((png_bytep buf, png_int_32 i));
  */
 PNG_EXTERN void png_save_uint_16 PNGARG((png_bytep buf, unsigned int i));
 
-/* Write a PNG chunk - size, type, (optional) data, CRC. */
-PNG_EXTERN void png_write_chunk PNGARG((png_structp png_ptr,
-   png_bytep chunk_name, png_bytep data, png_size_t length));
-
-/* Write the start of a PNG chunk - length and chunk name. */
-PNG_EXTERN void png_write_chunk_start PNGARG((png_structp png_ptr,
-   png_bytep chunk_name, png_uint_32 length));
-
-/* Write the data of a PNG chunk started with png_write_chunk_start(). */
-PNG_EXTERN void png_write_chunk_data PNGARG((png_structp png_ptr,
-   png_bytep data, png_size_t length));
-
-/* Finish a chunk started with png_write_chunk_start() (includes CRC). */
-PNG_EXTERN void png_write_chunk_end PNGARG((png_structp png_ptr));
-
-/* simple function to write the signiture */
+/* simple function to write the signature */
 PNG_EXTERN void png_write_sig PNGARG((png_structp png_ptr));
 
 /* write various chunks */
@@ -1604,7 +1694,7 @@ PNG_EXTERN void png_write_bKGD PNGARG((png_structp png_ptr,
 
 #if defined(PNG_WRITE_hIST_SUPPORTED)
 PNG_EXTERN void png_write_hIST PNGARG((png_structp png_ptr, png_uint_16p hist,
-   png_uint_32 num_hist));
+   int num_hist));
 #endif
 
 #if defined(PNG_WRITE_tEXt_SUPPORTED) || defined(PNG_WRITE_zTXt_SUPPORTED)

pngconf.h

@@ -1,12 +1,12 @@
 
-/* pngconf.c - machine configurable file for libpng
+/* pngconf.h - machine configurable file for libpng
  *
- * libpng 0.98
+ * libpng 0.99e
  * For conditions of distribution and use, see copyright notice in png.h
  * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
  * Copyright (c) 1996, 1997 Andreas Dilger
  * Copyright (c) 1998, Glenn Randers-Pehrson
- * January 16, 1998
+ * February 28, 1998
  */
 
 /* Any machine specific code is near the front of this file, so if you
@@ -27,7 +27,7 @@
  * where it becomes significant, if you are concerned with memory
  * usage.  Note that zlib allocates at least 32Kb also.  For readers,
  * this describes the size of the buffer available to read the data in.
- * Unless this gets smaller then the size of a row (compressed),
+ * Unless this gets smaller than the size of a row (compressed),
  * it should not make much difference how big this is.
  */
 
@@ -55,8 +55,6 @@
  * #define PNG_NO_STDIO
  */
 
-/* We still need stdio.h for FILE even when PNG_NO_STDIO is defined.
- */
 #ifndef PNG_NO_STDIO 
 #include <stdio.h>
 #endif
@@ -88,10 +86,12 @@
  * just __MWERKS__ is not good enough, because the Codewarrior is now used
  * on non-Mac platforms.
  */
+#ifndef MACOS
 #if (defined(__MWERKS__) && defined(macintosh)) || defined(applec) || \
-    defined(THINK_C) || defined(__SC__)
+    defined(THINK_C) || defined(__SC__) || defined(TARGET_OS_MAC)
 #define MACOS
 #endif
+#endif
 
 /* enough people need this for various reasons to include it here */
 #if !defined(MACOS) && !defined(RISCOS)
@@ -157,6 +157,11 @@ __dont__ include it again
 #include <math.h>
 #endif
 
+/* Codewarrior on NT has linking problems without this. */
+#if defined(__MWERKS__) && defined(WIN32)
+#define PNG_ALWAYS_EXTERN
+#endif
+
 /* For some reason, Borland C++ defines memcmp, etc. in mem.h, not
  * stdlib.h like it should (I think).  Or perhaps this is a C++
  * "feature"?
@@ -234,7 +239,8 @@ __dont__ include it again
 /* GR-P, 0.96a: Set "*FULLY_SUPPORTED as default but allow user
    to turn it off with "*NOT_FULLY_SUPPORTED" on the compile line,
    then pick and choose which ones to define without having to edit
-   this file */
+   this file.
+ */
 
 #ifndef PNG_READ_NOT_FULLY_SUPPORTED
 #define PNG_READ_FULLY_SUPPORTED
@@ -245,7 +251,6 @@ __dont__ include it again
 
 #ifdef PNG_READ_FULLY_SUPPORTED
 #define PNG_PROGRESSIVE_READ_SUPPORTED
-#define PNG_READ_OPT_PLTE_SUPPORTED
 #define PNG_READ_EXPAND_SUPPORTED
 #define PNG_READ_SHIFT_SUPPORTED
 #define PNG_READ_PACK_SUPPORTED
@@ -264,10 +269,10 @@ __dont__ include it again
 #define PNG_READ_STRIP_ALPHA_SUPPORTED
 #define PNG_READ_COMPOSITE_NODIV_SUPPORTED        /* well tested on Intel */
 #endif /* PNG_READ_FULLY_SUPPORTED */
-#define PNG_READ_INTERLACING_SUPPORTED
+
+#define PNG_READ_INTERLACING_SUPPORTED  /* required for PNG-compliant decoders */
 
 #ifdef PNG_WRITE_FULLY_SUPPORTED
-#define PNG_WRITE_INTERLACING_SUPPORTED
 #define PNG_WRITE_SHIFT_SUPPORTED
 #define PNG_WRITE_PACK_SUPPORTED
 #define PNG_WRITE_BGR_SUPPORTED
@@ -281,15 +286,39 @@ __dont__ include it again
 #define PNG_WRITE_WEIGHTED_FILTER_SUPPORTED
 #endif /* PNG_WRITE_FULLY_SUPPORTED */
 
+#define PNG_WRITE_INTERLACING_SUPPORTED  /* not required for PNG-compliant */
+                                         /* encoders, but can cause trouble
+                                            if left undefined */
+
 #if !defined(PNG_NO_STDIO)
 #define PNG_TIME_RFC1123_SUPPORTED
 #endif
 
+/* This adds extra functions in pngget.c for accessing data from the
+ * info pointer (added in version 0.99)
+ * png_get_image_width()
+ * png_get_image_height()
+ * png_get_bit_depth()
+ * png_get_color_type()
+ * png_get_compression_type()
+ * png_get_filter_type()
+ * png_get_interlace_type()
+ * png_get_pixel_aspect_ratio()
+ * png_get_pixels_per_meter()
+ * png_get_x_offset_pixels()
+ * png_get_y_offset_pixels()
+ * png_get_x_offset_microns()
+ * png_get_y_offset_microns()
+ */
+#if !defined(PNG_NO_EASY_ACCESS)
+#define PNG_EASY_ACCESS_SUPPORTED
+#endif
+
 /* These are currently experimental features, define them if you want */
 
 /* very little testing */
 /*
-#define PNG_READ_16_TO_8_ACCURATE_SHIFT_SUPPORTED
+#define PNG_READ_16_TO_8_ACCURATE_SCALE_SUPPORTED
 */
 
 /* This is only for PowerPC big-endian and 680x0 systems */
@@ -307,11 +336,17 @@ __dont__ include it again
 /* Any chunks you are not interested in, you can undef here.  The
  * ones that allocate memory may be expecially important (hIST,
  * tEXt, zTXt, tRNS, pCAL).  Others will just save time and make png_info
- * a bit smaller.  OPT_PLTE only disables the optional palette in RGB
- * and RGBA images.
+ * a bit smaller.
  */
 
-#ifdef PNG_READ_FULLY_SUPPORTED
+#ifndef PNG_READ_ANCILLARY_CHUNKS_NOT_SUPPORTED
+#define PNG_READ_ANCILLARY_CHUNKS_SUPPORTED
+#endif
+#ifndef PNG_WRITE_ANCILLARY_CHUNKS_NOT_SUPPORTED
+#define PNG_WRITE_ANCILLARY_CHUNKS_SUPPORTED
+#endif
+
+#ifdef PNG_READ_ANCILLARY_CHUNKS_SUPPORTED
 #define PNG_READ_bKGD_SUPPORTED
 #define PNG_READ_cHRM_SUPPORTED
 #define PNG_READ_gAMA_SUPPORTED
@@ -325,9 +360,11 @@ __dont__ include it again
 #define PNG_READ_tIME_SUPPORTED
 #define PNG_READ_tRNS_SUPPORTED
 #define PNG_READ_zTXt_SUPPORTED
-#endif /* PNG_READ_FULLY_SUPPORTED */
+#define PNG_READ_OPT_PLTE_SUPPORTED /* only affects support of the optional */
+                                    /* PLTE chunk in RGB and RGBA images */
+#endif /* PNG_READ_ANCILLARY_CHUNKS_SUPPORTED */
 
-#ifdef PNG_WRITE_FULLY_SUPPORTED
+#ifdef PNG_WRITE_ANCILLARY_CHUNKS_SUPPORTED
 #define PNG_WRITE_bKGD_SUPPORTED
 #define PNG_WRITE_cHRM_SUPPORTED
 #define PNG_WRITE_gAMA_SUPPORTED
@@ -341,7 +378,7 @@ __dont__ include it again
 #define PNG_WRITE_tIME_SUPPORTED
 #define PNG_WRITE_tRNS_SUPPORTED
 #define PNG_WRITE_zTXt_SUPPORTED
-#endif /* PNG_WRITE_FULLY_SUPPORTED */
+#endif /* PNG_WRITE_ANCILLARY_CHUNKS_SUPPORTED */
 
 /* need the time information for reading tIME chunks */
 #if defined(PNG_READ_tIME_SUPPORTED) || defined(PNG_WRITE_tIME_SUPPORTED)
@@ -467,7 +504,7 @@ typedef z_stream FAR *  png_zstreamp;
 
 /* allow for compilation as dll with BORLAND C++ 5.0 */
 #if defined(__BORLANDC__) && defined(_Windows) && defined(__DLL__)
-#   define PNG_EXPORT(t,s) t _export s
+#   define PNG_EXPORT(type,symbol) type _export symbol
 #endif
 
 /* allow for compilation as shared lib under BeOS */
@@ -476,7 +513,7 @@ typedef z_stream FAR *  png_zstreamp;
 #endif
 
 #ifndef PNG_EXPORT
-#define PNG_EXPORT(t,s) t s
+#define PNG_EXPORT(type,symbol) type symbol
 #endif
 
 
@@ -488,8 +525,8 @@ typedef z_stream FAR *  png_zstreamp;
 /* use this to make far-to-near assignments */
 #   define CHECK   1
 #   define NOCHECK 0
-#   define CVT_PTR(ptr) (far_to_near(png_ptr,ptr,CHECK))
-#   define CVT_PTR_NOCHECK(ptr) (far_to_near(png_ptr,ptr,NOCHECK))
+#   define CVT_PTR(ptr) (png_far_to_near(png_ptr,ptr,CHECK))
+#   define CVT_PTR_NOCHECK(ptr) (png_far_to_near(png_ptr,ptr,NOCHECK))
 #   define png_strlen _fstrlen
 #   define png_memcmp _fmemcmp      /* SJT: added */
 #   define png_memcpy _fmemcpy

pngerror.c

@@ -1,12 +1,12 @@
 
 /* pngerror.c - stub functions for i/o and memory allocation
  *
- * libpng 0.98
+ * libpng 0.99e
  * For conditions of distribution and use, see copyright notice in png.h
  * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
  * Copyright (c) 1996, 1997 Andreas Dilger
  * Copyright (c) 1998, Glenn Randers-Pehrson
- * January 16, 1998
+ * February 28, 1998
  *
  * This file provides a location for all error handling.  Users which
  * need special error handling are expected to write replacement functions
@@ -81,7 +81,7 @@ png_format_buffer(png_structp png_ptr, png_charp buffer, png_const_charp message
    }
 
    if (message == NULL)
-      buffer[iout++] = 0;
+      buffer[iout] = 0;
    else {
       buffer[iout++] = ':';
       buffer[iout++] = ' ';
@@ -167,7 +167,7 @@ png_set_error_fn(png_structp png_ptr, png_voidp error_ptr,
 png_voidp
 png_get_error_ptr(png_structp png_ptr)
 {
-   return png_ptr->error_ptr;
+   return ((png_voidp)png_ptr->error_ptr);
 }
 
 

pngget.c

@@ -1,12 +1,12 @@
 
 /* pngget.c - retrieval of values from info struct
  *
- * libpng 0.98
+ * libpng 0.99e
  * For conditions of distribution and use, see copyright notice in png.h
  * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
  * Copyright (c) 1996, 1997 Andreas Dilger
  * Copyright (c) 1998, Glenn Randers-Pehrson
- * January 16, 1998
+ * February 28, 1998
  */
 
 #define PNG_INTERNAL
@@ -15,7 +15,7 @@
 png_uint_32
 png_get_valid(png_structp png_ptr, png_infop info_ptr, png_uint_32 flag)
 {
-   if (info_ptr != NULL)
+   if (png_ptr != NULL && info_ptr != NULL)
       return(info_ptr->valid & flag);
    else
       return(0);
@@ -24,28 +24,307 @@ png_get_valid(png_structp png_ptr, png_infop info_ptr, png_uint_32 flag)
 png_uint_32
 png_get_rowbytes(png_structp png_ptr, png_infop info_ptr)
 {
-   if (info_ptr != NULL)
+   if (png_ptr != NULL && info_ptr != NULL)
       return(info_ptr->rowbytes);
    else
       return(0);
 }
 
+#ifdef PNG_EASY_ACCESS_SUPPORTED
+/* easy access to info, added in libpng-0.99 */
+png_uint_32
+png_get_image_width(png_structp png_ptr, png_infop info_ptr)
+{
+   if (png_ptr != NULL && info_ptr != NULL)
+   {
+      return info_ptr->width;
+   }
+   return (0);
+}
+
+png_uint_32
+png_get_image_height(png_structp png_ptr, png_infop info_ptr)
+{
+   if (png_ptr != NULL && info_ptr != NULL)
+   {
+      return info_ptr->height;
+   }
+   return (0);
+}
+
+png_byte
+png_get_bit_depth(png_structp png_ptr, png_infop info_ptr)
+{
+   if (png_ptr != NULL && info_ptr != NULL)
+   {
+      return info_ptr->bit_depth;
+   }
+   return (0);
+}
+
+png_byte
+png_get_color_type(png_structp png_ptr, png_infop info_ptr)
+{
+   if (png_ptr != NULL && info_ptr != NULL)
+   {
+      return info_ptr->color_type;
+   }
+   return (0);
+}
+
+png_byte
+png_get_filter_type(png_structp png_ptr, png_infop info_ptr)
+{
+   if (png_ptr != NULL && info_ptr != NULL)
+   {
+      return info_ptr->filter_type;
+   }
+   return (0);
+}
+
+png_byte
+png_get_interlace_type(png_structp png_ptr, png_infop info_ptr)
+{
+   if (png_ptr != NULL && info_ptr != NULL)
+   {
+      return info_ptr->interlace_type;
+   }
+   return (0);
+}
+
+png_byte
+png_get_compression_type(png_structp png_ptr, png_infop info_ptr)
+{
+   if (png_ptr != NULL && info_ptr != NULL)
+   {
+      return info_ptr->compression_type;
+   }
+   return (0);
+}
+
+png_uint_32
+png_get_x_pixels_per_meter(png_structp png_ptr, png_infop info_ptr)
+{
+#if defined(PNG_READ_pHYs_SUPPORTED) || defined(PNG_WRITE_pHYs_SUPPORTED)
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs))
+   {
+      png_debug1(1, "in %s retrieval function\n", "png_get_x_pixels_per_meter");
+      if(info_ptr->phys_unit_type != PNG_RESOLUTION_METER)
+          return (0);
+      else return (info_ptr->x_pixels_per_unit);
+   }
+   else
+#endif
+   return (0);
+}
+
+png_uint_32
+png_get_y_pixels_per_meter(png_structp png_ptr, png_infop info_ptr)
+{
+#if defined(PNG_READ_pHYs_SUPPORTED) || defined(PNG_WRITE_pHYs_SUPPORTED)
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs))
+   {
+      png_debug1(1, "in %s retrieval function\n", "png_get_y_pixels_per_meter");
+      if(info_ptr->phys_unit_type != PNG_RESOLUTION_METER)
+          return (0);
+      else return (info_ptr->y_pixels_per_unit);
+   }
+   else
+#endif
+   return (0);
+}
+
+png_uint_32
+png_get_pixels_per_meter(png_structp png_ptr, png_infop info_ptr)
+{
+#if defined(PNG_READ_pHYs_SUPPORTED) || defined(PNG_WRITE_pHYs_SUPPORTED)
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs))
+   {
+      png_debug1(1, "in %s retrieval function\n", "png_get_pixels_per_meter");
+      if(info_ptr->phys_unit_type != PNG_RESOLUTION_METER ||
+         info_ptr->x_pixels_per_unit != info_ptr->y_pixels_per_unit)
+          return (0);
+      else return (info_ptr->x_pixels_per_unit);
+   }
+   else
+#endif
+   return (0);
+}
+
+float
+png_get_pixel_aspect_ratio(png_structp png_ptr, png_infop info_ptr)
+   {
+#if defined(PNG_READ_pHYs_SUPPORTED) || defined(PNG_WRITE_pHYs_SUPPORTED)
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs))
+   {
+      png_debug1(1, "in %s retrieval function\n", "png_get_aspect_ratio");
+      if (info_ptr->x_pixels_per_unit == 0)
+         return ((float)0.0);
+      else
+         return ((float)info_ptr->y_pixels_per_unit
+            /(float)info_ptr->x_pixels_per_unit);
+   }
+   else
+#endif
+      return ((float)0.0);
+}
+
+png_uint_32
+png_get_x_offset_microns(png_structp png_ptr, png_infop info_ptr)
+{
+#if defined(PNG_READ_oFFs_SUPPORTED) || defined(PNG_WRITE_oFFs_SUPPORTED)
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs))
+   {
+      png_debug1(1, "in %s retrieval function\n", "png_get_x_offset_microns");
+      if(info_ptr->offset_unit_type != PNG_OFFSET_MICROMETER)
+          return (0);
+      else return (info_ptr->x_offset);
+   }
+   else
+#endif
+   return (0);
+}
+
+png_uint_32
+png_get_y_offset_microns(png_structp png_ptr, png_infop info_ptr)
+{
+#if defined(PNG_READ_oFFs_SUPPORTED) || defined(PNG_WRITE_oFFs_SUPPORTED)
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs))
+   {
+      png_debug1(1, "in %s retrieval function\n", "png_get_y_offset_microns");
+      if(info_ptr->offset_unit_type != PNG_OFFSET_MICROMETER)
+          return (0);
+      else return (info_ptr->y_offset);
+   }
+   else
+#endif
+   return (0);
+}
+
+png_uint_32
+png_get_x_offset_pixels(png_structp png_ptr, png_infop info_ptr)
+{
+#if defined(PNG_READ_oFFs_SUPPORTED) || defined(PNG_WRITE_oFFs_SUPPORTED)
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs))
+   {
+      png_debug1(1, "in %s retrieval function\n", "png_get_x_offset_microns");
+      if(info_ptr->offset_unit_type != PNG_OFFSET_PIXEL)
+          return (0);
+      else return (info_ptr->x_offset);
+   }
+   else
+#endif
+   return (0);
+}
+
+png_uint_32
+png_get_y_offset_pixels(png_structp png_ptr, png_infop info_ptr)
+{
+#if defined(PNG_READ_oFFs_SUPPORTED) || defined(PNG_WRITE_oFFs_SUPPORTED)
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs))
+   {
+      png_debug1(1, "in %s retrieval function\n", "png_get_y_offset_microns");
+      if(info_ptr->offset_unit_type != PNG_OFFSET_PIXEL)
+          return (0);
+      else return (info_ptr->y_offset);
+   }
+   else
+#endif
+   return (0);
+}
+
+#ifdef PNG_INCH_CONVERSIONS
+png_uint_32
+png_get_pixels_per_inch(png_structp png_ptr, png_infop info_ptr)
+{
+   return ((png_uint_32)((float)png_get_pixels_per_meter(png_ptr, info_ptr)
+     *.03937 +.5)
+}
+
+png_uint_32
+png_get_x_pixels_per_inch(png_structp png_ptr, png_infop info_ptr)
+{
+   return ((png_uint_32)((float)png_get_x_pixels_per_meter(png_ptr, info_ptr)
+     *.03937 +.5)
+}
+
+png_uint_32
+png_get_y_pixels_per_inch(png_structp png_ptr, png_infop info_ptr)
+{
+   return ((png_uint_32)((float)png_get_y_pixels_per_meter(png_ptr, info_ptr)
+     *.03937 +.5)
+}
+
+float
+png_get_x_offset_inches(png_structp png_ptr, png_infop info_ptr)
+{
+   return ((float)png_get_x_offset_microns(png_ptr, info_ptr)
+     *.03937/1000000. +.5)
+}
+
+float
+png_get_y_offset_inches(png_structp png_ptr, png_infop info_ptr)
+{
+   return ((float)png_get_y_offset_microns(png_ptr, info_ptr)
+     *.03937/1000000. +.5)
+}
+
+#if defined(PNG_READ_pHYs_SUPPORTED)
+png_uint_32
+png_get_pHYs_dpi(png_structp png_ptr, png_infop info_ptr,
+   png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type)
+{
+   png_uint_32 retval = 0;
+
+   if (png_ptr != NULL && info_ptr != NULL && info_ptr->valid & PNG_INFO_pHYs)
+   {
+      png_debug1(1, "in %s retrieval function\n", "pHYs");
+      if (res_x != NULL)
+      {
+         *res_x = info_ptr->x_pixels_per_unit;
+         retval |= PNG_INFO_pHYs;
+      }
+      if (res_y != NULL)
+      {
+         *res_y = info_ptr->y_pixels_per_unit;
+         retval |= PNG_INFO_pHYs;
+      }
+      if (unit_type != NULL)
+      {
+         *unit_type = (int)info_ptr->phys_unit_type;
+         retval |= PNG_INFO_pHYs;
+         if(unit_type == 1)
+         {
+            if (res_x != NULL) *res_x = (png_uint_32)(*res_x * 39.37 + .50);
+            if (res_y != NULL) *res_y = (png_uint_32)(*res_y * 39.37 + .50);
+         }
+      }
+   }
+   return (retval);
+}
+#endif
+
+#endif  /* PNG_INCH_CONVERSIONS */
+
+/* png_get_channels really belongs in here, too, but it's been around longer */
+#endif  /* PNG_EASY_ACCESS_SUPPORTED */
+
 png_byte
 png_get_channels(png_structp png_ptr, png_infop info_ptr)
 {
-   if (info_ptr != NULL)
+   if (png_ptr != NULL && info_ptr != NULL)
       return(info_ptr->channels);
    else
-      return(0);
+      return (0);
 }
 
 png_bytep
 png_get_signature(png_structp png_ptr, png_infop info_ptr)
 {
-   if (info_ptr != NULL)
+   if (png_ptr != NULL && info_ptr != NULL)
       return(info_ptr->signature);
    else
-      return(NULL);
+      return (NULL);
 }
 
 #if defined(PNG_READ_bKGD_SUPPORTED)
@@ -53,8 +332,8 @@ png_uint_32
 png_get_bKGD(png_structp png_ptr, png_infop info_ptr,
    png_color_16p *background)
 {
-   if (info_ptr != NULL && info_ptr->valid & PNG_INFO_bKGD &&
-      background != NULL)
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_bKGD)
+      && background != NULL)
    {
       png_debug1(1, "in %s retrieval function\n", "bKGD");
       *background = &(info_ptr->background);
@@ -70,7 +349,7 @@ png_get_cHRM(png_structp png_ptr, png_infop info_ptr,
    double *white_x, double *white_y, double *red_x, double *red_y,
    double *green_x, double *green_y, double *blue_x, double *blue_y)
 {
-   if (info_ptr != NULL && info_ptr->valid & PNG_INFO_cHRM)
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_cHRM))
    {
       png_debug1(1, "in %s retrieval function\n", "cHRM");
       if (white_x != NULL)
@@ -99,8 +378,8 @@ png_get_cHRM(png_structp png_ptr, png_infop info_ptr,
 png_uint_32
 png_get_gAMA(png_structp png_ptr, png_infop info_ptr, double *file_gamma)
 {
-   if (info_ptr != NULL && info_ptr->valid & PNG_INFO_gAMA &&
-      file_gamma != NULL)
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_gAMA)
+      && file_gamma != NULL)
    {
       png_debug1(1, "in %s retrieval function\n", "gAMA");
       *file_gamma = (double)info_ptr->gamma;
@@ -114,8 +393,8 @@ png_get_gAMA(png_structp png_ptr, png_infop info_ptr, double *file_gamma)
 png_uint_32
 png_get_sRGB(png_structp png_ptr, png_infop info_ptr, int *file_srgb_intent)
 {
-   if (info_ptr != NULL && info_ptr->valid & PNG_INFO_sRGB &&
-      file_srgb_intent != NULL)
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_sRGB)
+      && file_srgb_intent != NULL)
    {
       png_debug1(1, "in %s retrieval function\n", "sRGB");
       *file_srgb_intent = (int)info_ptr->srgb_intent;
@@ -129,7 +408,8 @@ png_get_sRGB(png_structp png_ptr, png_infop info_ptr, int *file_srgb_intent)
 png_uint_32
 png_get_hIST(png_structp png_ptr, png_infop info_ptr, png_uint_16p *hist)
 {
-   if (info_ptr != NULL && info_ptr->valid & PNG_INFO_hIST && hist != NULL)
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_hIST)
+      && hist != NULL)
    {
       png_debug1(1, "in %s retrieval function\n", "hIST");
       *hist = info_ptr->hist;
@@ -146,9 +426,12 @@ png_get_IHDR(png_structp png_ptr, png_infop info_ptr,
    int *filter_type)
    
 {
-   if (info_ptr != NULL && width != NULL && height != NULL &&
+   if (png_ptr != NULL && info_ptr != NULL && width != NULL && height != NULL &&
       bit_depth != NULL && color_type != NULL)
    {
+      int pixel_depth, channels;
+      png_uint_32 rowbytes_per_pixel;
+
       png_debug1(1, "in %s retrieval function\n", "IHDR");
       *width = info_ptr->width;
       *height = info_ptr->height;
@@ -160,6 +443,23 @@ png_get_IHDR(png_structp png_ptr, png_infop info_ptr,
          *filter_type = info_ptr->filter_type;
       if (interlace_type != NULL)
          *interlace_type = info_ptr->interlace_type;
+
+      /* check for potential overflow of rowbytes */
+      if (*color_type == PNG_COLOR_TYPE_PALETTE)
+         channels = 1;
+      else if (*color_type & PNG_COLOR_MASK_COLOR)
+         channels = 3;
+      else
+         channels = 1;
+      if (*color_type & PNG_COLOR_MASK_ALPHA)
+         channels++;
+      pixel_depth = *bit_depth * channels;
+      rowbytes_per_pixel = (pixel_depth + 7) >> 3;
+      if ((*width > (png_uint_32)2147483647L/rowbytes_per_pixel))
+      {
+         png_warning(png_ptr,
+            "Width too large for libpng to process image data.");
+      }
       return (1);
    }
    return (0);
@@ -170,8 +470,8 @@ png_uint_32
 png_get_oFFs(png_structp png_ptr, png_infop info_ptr,
    png_uint_32 *offset_x, png_uint_32 *offset_y, int *unit_type)
 {
-   if (info_ptr != NULL && info_ptr->valid & PNG_INFO_oFFs &&
-      offset_x != NULL && offset_y != NULL && unit_type != NULL)
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs)
+      && offset_x != NULL && offset_y != NULL && unit_type != NULL)
    {
       png_debug1(1, "in %s retrieval function\n", "oFFs");
       *offset_x = info_ptr->x_offset;
@@ -189,7 +489,7 @@ png_get_pCAL(png_structp png_ptr, png_infop info_ptr,
    png_charp *purpose, png_int_32 *X0, png_int_32 *X1, int *type, int *nparams,
    png_charp *units, png_charpp *params)
 {
-   if (info_ptr != NULL && info_ptr->valid & PNG_INFO_pCAL &&
+   if (png_ptr != NULL && info_ptr != NULL && info_ptr->valid & PNG_INFO_pCAL &&
       purpose != NULL && X0 != NULL && X1 != NULL && type != NULL &&
       nparams != NULL && units != NULL && params != NULL)
    {
@@ -214,12 +514,16 @@ png_get_pHYs(png_structp png_ptr, png_infop info_ptr,
 {
    png_uint_32 retval = 0;
 
-   if (info_ptr != NULL && info_ptr->valid & PNG_INFO_pHYs)
+   if (png_ptr != NULL && info_ptr != NULL && info_ptr->valid & PNG_INFO_pHYs)
    {
       png_debug1(1, "in %s retrieval function\n", "pHYs");
-      if (res_x != NULL && res_y != NULL)
+      if (res_x != NULL)
       {
          *res_x = info_ptr->x_pixels_per_unit;
+         retval |= PNG_INFO_pHYs;
+      }
+      if (res_y != NULL)
+      {
          *res_y = info_ptr->y_pixels_per_unit;
          retval |= PNG_INFO_pHYs;
       }
@@ -228,9 +532,8 @@ png_get_pHYs(png_structp png_ptr, png_infop info_ptr,
          *unit_type = (int)info_ptr->phys_unit_type;
          retval |= PNG_INFO_pHYs;
       }
-      return (retval);
    }
-   return (0);
+   return (retval);
 }
 #endif
 
@@ -238,7 +541,8 @@ png_uint_32
 png_get_PLTE(png_structp png_ptr, png_infop info_ptr, png_colorp *palette,
    int *num_palette)
 {
-   if (info_ptr != NULL && info_ptr->valid & PNG_INFO_PLTE && palette != NULL)
+   if (png_ptr != NULL && info_ptr != NULL && info_ptr->valid & PNG_INFO_PLTE &&
+       palette != NULL)
    {
       png_debug1(1, "in %s retrieval function\n", "PLTE");
       *palette = info_ptr->palette;
@@ -253,7 +557,8 @@ png_get_PLTE(png_structp png_ptr, png_infop info_ptr, png_colorp *palette,
 png_uint_32
 png_get_sBIT(png_structp png_ptr, png_infop info_ptr, png_color_8p *sig_bit)
 {
-   if (info_ptr != NULL && info_ptr->valid & PNG_INFO_sBIT && sig_bit != NULL)
+   if (png_ptr != NULL && info_ptr != NULL && info_ptr->valid & PNG_INFO_sBIT &&
+       sig_bit != NULL)
    {
       png_debug1(1, "in %s retrieval function\n", "sBIT");
       *sig_bit = &(info_ptr->sig_bit);
@@ -268,7 +573,7 @@ png_uint_32
 png_get_text(png_structp png_ptr, png_infop info_ptr, png_textp *text_ptr,
    int *num_text)
 {
-   if ((info_ptr != NULL) || (info_ptr->num_text > 0))
+   if (png_ptr != NULL && info_ptr != NULL && info_ptr->num_text > 0)
    {
       png_debug1(1, "in %s retrieval function\n",
          (png_ptr->chunk_name[0] == '\0' ? "text"
@@ -287,7 +592,8 @@ png_get_text(png_structp png_ptr, png_infop info_ptr, png_textp *text_ptr,
 png_uint_32
 png_get_tIME(png_structp png_ptr, png_infop info_ptr, png_timep *mod_time)
 {
-   if (info_ptr != NULL && info_ptr->valid & PNG_INFO_tIME && mod_time != NULL)
+   if (png_ptr != NULL && info_ptr != NULL && info_ptr->valid & PNG_INFO_tIME &&
+       mod_time != NULL)
    {
       png_debug1(1, "in %s retrieval function\n", "tIME");
       *mod_time = &(info_ptr->mod_time);
@@ -302,25 +608,37 @@ png_uint_32
 png_get_tRNS(png_structp png_ptr, png_infop info_ptr,
    png_bytep *trans, int *num_trans, png_color_16p *trans_values)
 {
-   if (info_ptr != NULL && info_ptr->valid & PNG_INFO_tRNS)
+   png_uint_32 retval = 0;
+   if (png_ptr != NULL && info_ptr != NULL && info_ptr->valid & PNG_INFO_tRNS)
    {
       png_debug1(1, "in %s retrieval function\n", "tRNS");
-      if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE && trans != NULL)
+      if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
       {
-          *trans = info_ptr->trans;
+          if (trans != NULL)
+          {
+             *trans = info_ptr->trans;
+             retval |= PNG_INFO_tRNS;
+          }
+          if (trans_values != NULL)
+             *trans_values = &(info_ptr->trans_values);
       }
-      else if (trans_values != NULL)
+      else /* if (info_ptr->color_type != PNG_COLOR_TYPE_PALETTE) */
       {
-         *trans_values = &(info_ptr->trans_values);
+          if (trans_values != NULL)
+          {
+             *trans_values = &(info_ptr->trans_values);
+             retval |= PNG_INFO_tRNS;
+          }
+          if(trans != NULL)
+             *trans = NULL;
       }
-      else
+      if(num_trans != NULL)
       {
-         return (0);
+         *num_trans = info_ptr->num_trans;
+         retval |= PNG_INFO_tRNS;
       }
-      *num_trans = info_ptr->num_trans;
-      return (PNG_INFO_tRNS);
    }
-   return (0);
+   return (retval);
 }
 #endif
 

pngmem.c

@@ -1,11 +1,11 @@
 /* pngmem.c - stub functions for memory allocation
  *
- * libpng 0.98
+ * libpng 0.99e
  * For conditions of distribution and use, see copyright notice in png.h
  * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
  * Copyright (c) 1996, 1997 Andreas Dilger
  * Copyright (c) 1998, Glenn Randers-Pehrson
- * January 16, 1998
+ * February 28, 1998
  *
  * This file provides a location for all memory allocation.  Users which
  * need special memory handling are expected to modify the code in this file
@@ -42,7 +42,7 @@ png_create_struct(int type)
    else if (type == PNG_STRUCT_PNG)
      size = sizeof(png_struct);
    else
-     return (png_voidp)NULL;
+     return ((png_voidp)NULL);
 
    if ((struct_ptr = (png_voidp)farmalloc(size)) != NULL)
    {
@@ -58,7 +58,10 @@ void
 png_destroy_struct(png_voidp struct_ptr)
 {
    if (struct_ptr != NULL)
+   {
       farfree (struct_ptr);
+      struct_ptr = NULL;
+   }
 }
 
 /* Allocate memory.  For reasonable files, size should never exceed
@@ -85,7 +88,7 @@ PNG_MALLOC(png_structp png_ptr, png_uint_32 size)
 {
    png_voidp ret;
    if (png_ptr == NULL || size == 0)
-      return ((voidp)NULL);
+      return ((png_voidp)NULL);
 
 #ifdef PNG_MAX_MALLOC_64K
    if (size > (png_uint_32)65536L)
@@ -107,8 +110,10 @@ PNG_MALLOC(png_structp png_ptr, png_uint_32 size)
             png_byte huge * hptr;
 
             if (ret != NULL)
+            {
                farfree(ret);
-            ret = NULL;
+               ret = NULL;
+            }
 
             num_blocks = (int)(1 << (png_ptr->zlib_window_bits - 14));
             if (num_blocks < 1)
@@ -124,7 +129,7 @@ PNG_MALLOC(png_structp png_ptr, png_uint_32 size)
 
             if (table == NULL)
             {
-               png_error(png_ptr, "Out of Memory");
+               png_error(png_ptr, "Out Of Memory."); /* Note "O" and "M" */
             }
 
             if ((png_size_t)table & 0xfff0)
@@ -138,7 +143,7 @@ PNG_MALLOC(png_structp png_ptr, png_uint_32 size)
 
             if (png_ptr->offset_table_ptr == NULL)
             {
-               png_error(png_ptr, "Out of memory");
+               png_error(png_ptr, "Out Of memory.");
             }
 
             hptr = (png_byte huge *)table;
@@ -160,7 +165,7 @@ PNG_MALLOC(png_structp png_ptr, png_uint_32 size)
       }
 
       if (png_ptr->offset_table_count >= png_ptr->offset_table_number)
-         png_error(png_ptr, "Out of Memory");
+         png_error(png_ptr, "Out of Memory.");
 
       ret = png_ptr->offset_table_ptr[png_ptr->offset_table_count++];
    }
@@ -169,10 +174,10 @@ PNG_MALLOC(png_structp png_ptr, png_uint_32 size)
 
    if (ret == NULL)
    {
-      png_error(png_ptr, "Out of Memory");
+      png_error(png_ptr, "Out of memory."); /* Note "o" and "m" */
    }
 
-   return ret;
+   return (ret);
 }
 
 /* free a pointer allocated by PNG_MALLOC().  In the default
@@ -207,7 +212,10 @@ PNG_FREE(png_structp png_ptr, png_voidp ptr)
    }
 
    if (ptr != NULL)
+   {
       farfree(ptr);
+      ptr = NULL;
+   }
 }
 
 #else /* Not the Borland DOS special memory handler */
@@ -226,7 +234,7 @@ png_create_struct(int type)
    else if (type == PNG_STRUCT_PNG)
       size = sizeof(png_struct);
    else
-      return (png_voidp)NULL;
+      return ((png_voidp)NULL);
 
 #if defined(__TURBOC__) && !defined(__FLAT__)
    if ((struct_ptr = (png_voidp)farmalloc(size)) != NULL)
@@ -250,6 +258,7 @@ void
 png_destroy_struct(png_voidp struct_ptr)
 {
    if (struct_ptr != NULL)
+   {
 #if defined(__TURBOC__) && !defined(__FLAT__)
       farfree(struct_ptr);
 #else
@@ -259,6 +268,7 @@ png_destroy_struct(png_voidp struct_ptr)
       free(struct_ptr);
 # endif
 #endif
+   }
 }
 
 
@@ -272,8 +282,9 @@ png_voidp
 PNG_MALLOC(png_structp png_ptr, png_uint_32 size)
 {
    png_voidp ret;
+
    if (png_ptr == NULL || size == 0)
-      return (NULL);
+      return ((png_voidp)NULL);
 
 #ifdef PNG_MAX_MALLOC_64K
    if (size > (png_uint_32)65536L)
@@ -281,12 +292,12 @@ PNG_MALLOC(png_structp png_ptr, png_uint_32 size)
 #endif
 
 #if defined(__TURBOC__) && !defined(__FLAT__)
-   ret = farmalloc((png_size_t)size);
+   ret = farmalloc(size);
 #else
 # if defined(_MSC_VER) && defined(MAXSEG_64K)
    ret = halloc(size, 1);
 # else
-   ret = malloc(size);
+   ret = malloc((size_t)size);
 # endif
 #endif
 
@@ -295,7 +306,7 @@ PNG_MALLOC(png_structp png_ptr, png_uint_32 size)
       png_error(png_ptr, "Out of Memory");
    }
 
-   return ret;
+   return (ret);
 }
 
 /* Free a pointer allocated by PNG_MALLOC().  In the default
@@ -320,3 +331,29 @@ PNG_FREE(png_structp png_ptr, png_voidp ptr)
 
 #endif /* Not Borland DOS special memory handler */
 
+png_voidp
+png_memcpy_check (png_structp png_ptr, png_voidp s1, png_voidp s2,
+   png_uint_32 length)
+{
+   png_size_t size;
+
+   size = (png_size_t)length;
+   if ((png_uint_32)size != length)
+      png_error(png_ptr,"Overflow in png_memcpy_check.");
+  
+   return(png_memcpy (s1, s2, size));
+}
+
+png_voidp
+png_memset_check (png_structp png_ptr, png_voidp s1, int value,
+   png_uint_32 length)
+{
+   png_size_t size;
+
+   size = (png_size_t)length;
+   if ((png_uint_32)size != length)
+      png_error(png_ptr,"Overflow in png_memset_check.");
+
+   return (png_memset (s1, value, size));
+
+}

pngpread.c

@@ -1,12 +1,12 @@
 
 /* pngpread.c - read a png file in push mode
  *
- * libpng 0.98
+ * libpng 0.99e
  * For conditions of distribution and use, see copyright notice in png.h
  * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
  * Copyright (c) 1996, 1997 Andreas Dilger
  * Copyright (c) 1998, Glenn Randers-Pehrson
- * January 16, 1998
+ * February 28, 1998
  */
 
 #define PNG_INTERNAL
@@ -466,7 +466,8 @@ png_push_save_buffer(png_structp png_ptr)
 
       new_max = png_ptr->save_buffer_size + png_ptr->current_buffer_size + 256;
       old_buffer = png_ptr->save_buffer;
-      png_ptr->save_buffer = (png_bytep)png_malloc(png_ptr, new_max);
+      png_ptr->save_buffer = (png_bytep)png_malloc(png_ptr, 
+         (png_uint_32)new_max);
       png_memcpy(png_ptr->save_buffer, old_buffer, png_ptr->save_buffer_size);
       png_free(png_ptr, old_buffer);
       png_ptr->save_buffer_max = new_max;
@@ -527,7 +528,12 @@ png_push_read_IDAT(png_structp png_ptr)
       png_size_t save_size;
 
       if (png_ptr->idat_size < (png_uint_32)png_ptr->save_buffer_size)
-         save_size = png_ptr->idat_size;
+      {
+         save_size = (png_size_t)png_ptr->idat_size;
+         /* check for overflow */
+         if((png_uint_32)save_size != png_ptr->idat_size)
+            png_error(png_ptr, "save_size overflowed in pngpread");
+      }
       else
          save_size = png_ptr->save_buffer_size;
 
@@ -544,7 +550,12 @@ png_push_read_IDAT(png_structp png_ptr)
       png_size_t save_size;
 
       if (png_ptr->idat_size < (png_uint_32)png_ptr->current_buffer_size)
-         save_size = png_ptr->idat_size;
+      {
+         save_size = (png_size_t)png_ptr->idat_size;
+         /* check for overflow */
+         if((png_uint_32)save_size != png_ptr->idat_size)
+            png_error(png_ptr, "save_size overflowed in pngpread");
+      }
       else
          save_size = png_ptr->current_buffer_size;
 
@@ -619,6 +630,7 @@ png_push_process_row(png_structp png_ptr)
    png_ptr->row_info.channels = png_ptr->channels;
    png_ptr->row_info.bit_depth = png_ptr->bit_depth;
    png_ptr->row_info.pixel_depth = png_ptr->pixel_depth;
+   
    png_ptr->row_info.rowbytes = ((png_ptr->row_info.width *
       (png_uint_32)png_ptr->row_info.pixel_depth + 7) >> 3);
 
@@ -626,7 +638,8 @@ png_push_process_row(png_structp png_ptr)
       png_ptr->row_buf + 1, png_ptr->prev_row + 1,
       (int)(png_ptr->row_buf[0]));
 
-   png_memcpy(png_ptr->prev_row, png_ptr->row_buf, png_ptr->rowbytes + 1);
+   png_memcpy_check(png_ptr, png_ptr->prev_row, png_ptr->row_buf,
+      png_ptr->rowbytes + 1);
 
    if (png_ptr->transformations)
       png_do_read_transformations(png_ptr);
@@ -761,7 +774,8 @@ png_read_push_finish_row(png_structp png_ptr)
    if (png_ptr->interlaced)
    {
       png_ptr->row_number = 0;
-      png_memset(png_ptr->prev_row, 0, png_ptr->rowbytes + 1);
+      png_memset_check(png_ptr, png_ptr->prev_row, 0,
+         png_ptr->rowbytes + 1);
       do
       {
          png_ptr->pass++;
@@ -771,8 +785,7 @@ png_read_push_finish_row(png_structp png_ptr)
             png_pass_inc[png_ptr->pass] - 1 -
             png_pass_start[png_ptr->pass]) /
             png_pass_inc[png_ptr->pass];
-         png_ptr->irowbytes = ((png_ptr->iwidth *
-            png_ptr->pixel_depth + 7) >> 3) + 1;
+         png_ptr->irowbytes = ((png_ptr->pixel_depth + 7) >> 3) + 1;
          if (!(png_ptr->transformations & PNG_INTERLACE))
          {
             png_ptr->num_rows = (png_ptr->height +
@@ -793,7 +806,11 @@ void
 png_push_handle_tEXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
 {
    if (png_ptr->mode == PNG_BEFORE_IHDR || png_ptr->mode & PNG_HAVE_IEND)
-      png_error(png_ptr, "Out of place tEXt");
+      {
+         png_error(png_ptr, "Out of place tEXt");
+         /* to quiet some compiler warnings */
+         if(info_ptr == NULL) return;
+      }
 
 #ifdef PNG_MAX_MALLOC_64K
    png_ptr->skip_length = 0;  /* This may not be necessary */
@@ -806,11 +823,12 @@ png_push_handle_tEXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length
    }
 #endif
 
-   png_ptr->current_text = (png_charp)png_malloc(png_ptr, length+1);
+   png_ptr->current_text = (png_charp)png_malloc(png_ptr, 
+         (png_uint_32)(length+1));
    png_ptr->current_text[length] = '\0';
    png_ptr->current_text_ptr = png_ptr->current_text;
-   png_ptr->current_text_size = length;
-   png_ptr->current_text_left = length;
+   png_ptr->current_text_size = (png_size_t)length;
+   png_ptr->current_text_left = (png_size_t)length;
    png_ptr->process_mode = PNG_READ_tEXt_MODE;
 }
 
@@ -857,7 +875,7 @@ png_push_read_tEXt(png_structp png_ptr, png_infop info_ptr)
       if (text != key + png_ptr->current_text_size)
          text++;
 
-      text_ptr = (png_textp)png_malloc(png_ptr, sizeof(png_text));
+      text_ptr = (png_textp)png_malloc(png_ptr, (png_uint_32)sizeof(png_text));
       text_ptr->compression = PNG_TEXT_COMPRESSION_NONE;
       text_ptr->key = key;
       text_ptr->text = text;
@@ -874,7 +892,11 @@ void
 png_push_handle_zTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
 {
    if (png_ptr->mode == PNG_BEFORE_IHDR || png_ptr->mode & PNG_HAVE_IEND)
-      png_error(png_ptr, "Out of place zTXt");
+      {
+         png_error(png_ptr, "Out of place zTXt");
+         /* to quiet some compiler warnings */
+         if(info_ptr == NULL) return;
+      }
 
 #ifdef PNG_MAX_MALLOC_64K
    /* We can't handle zTXt chunks > 64K, since we don't have enough space
@@ -889,11 +911,12 @@ png_push_handle_zTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length
    }
 #endif
 
-   png_ptr->current_text = (png_charp)png_malloc(png_ptr, length+1);
+   png_ptr->current_text = (png_charp)png_malloc(png_ptr,
+       (png_uint_32)(length+1));
    png_ptr->current_text[length] = '\0';
    png_ptr->current_text_ptr = png_ptr->current_text;
-   png_ptr->current_text_size = length;
-   png_ptr->current_text_left = length;
+   png_ptr->current_text_size = (png_size_t)length;
+   png_ptr->current_text_left = (png_size_t)length;
    png_ptr->process_mode = PNG_READ_zTXt_MODE;
 }
 
@@ -978,8 +1001,8 @@ png_push_read_zTXt(png_structp png_ptr, png_infop info_ptr)
             if (text == NULL)
             {
                text = (png_charp)png_malloc(png_ptr,
-                  png_ptr->zbuf_size - png_ptr->zstream.avail_out +
-                     key_size + 1);
+                  (png_uint_32)(png_ptr->zbuf_size - png_ptr->zstream.avail_out +
+                     key_size + 1));
                png_memcpy(text + key_size, png_ptr->zbuf,
                   png_ptr->zbuf_size - png_ptr->zstream.avail_out);
                png_memcpy(text, key, key_size);
@@ -992,8 +1015,9 @@ png_push_read_zTXt(png_structp png_ptr, png_infop info_ptr)
                png_charp tmp;
 
                tmp = text;
-               text = png_malloc(png_ptr, text_size +
-                  png_ptr->zbuf_size - png_ptr->zstream.avail_out + 1);
+               text = (png_charp)png_malloc(png_ptr, text_size +
+                  (png_uint_32)(png_ptr->zbuf_size - png_ptr->zstream.avail_out
+                   + 1));
                png_memcpy(text, tmp, text_size);
                png_free(png_ptr, tmp);
                png_memcpy(text + text_size, png_ptr->zbuf,
@@ -1029,9 +1053,8 @@ png_push_read_zTXt(png_structp png_ptr, png_infop info_ptr)
       png_free(png_ptr, key);
       key = text;
       text += key_size;
-      text_size -= key_size;
 
-      text_ptr = (png_textp)png_malloc(png_ptr, sizeof(png_text));
+      text_ptr = (png_textp)png_malloc(png_ptr, (png_uint_32)sizeof(png_text));
       text_ptr->compression = PNG_TEXT_COMPRESSION_zTXt;
       text_ptr->key = key;
       text_ptr->text = text;
@@ -1058,6 +1081,8 @@ png_push_handle_unknown(png_structp png_ptr, png_infop info_ptr, png_uint_32 len
    if (!(png_ptr->chunk_name[0] & 0x20))
    {
       png_chunk_error(png_ptr, "unknown critical chunk");
+      /* to quiet some compiler warnings */
+      if(info_ptr == NULL) return;
    }
 
    png_push_crc_skip(png_ptr, length);

pngread.c

@@ -1,12 +1,12 @@
 
 /* pngread.c - read a PNG file
  *
- * libpng 0.98
+ * libpng 0.99e
  * For conditions of distribution and use, see copyright notice in png.h
  * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
  * Copyright (c) 1996, 1997 Andreas Dilger
  * Copyright (c) 1998, Glenn Randers-Pehrson
- * January 16, 1998
+ * February 28, 1998
  *
  * This file contains routines that an application calls directly to
  * read a PNG file or stream.
@@ -17,7 +17,7 @@
 
 /* Create a PNG structure for reading, and allocate any memory needed. */
 png_structp
-png_create_read_struct(png_const_charp user_png_ver, png_voidp error_ptr,
+png_create_read_struct(png_const_charp user_png_ver, voidp error_ptr,
    png_error_ptr error_fn, png_error_ptr warn_fn)
 {
    png_structp png_ptr;
@@ -58,7 +58,8 @@ png_create_read_struct(png_const_charp user_png_ver, png_voidp error_ptr,
 
    /* initialize zbuf - compression buffer */
    png_ptr->zbuf_size = PNG_ZBUF_SIZE;
-   png_ptr->zbuf = png_malloc(png_ptr, png_ptr->zbuf_size);
+   png_ptr->zbuf = (png_bytep)png_malloc(png_ptr,
+     (png_uint_32)png_ptr->zbuf_size);
    png_ptr->zstream.zalloc = png_zalloc;
    png_ptr->zstream.zfree = png_zfree;
    png_ptr->zstream.opaque = (voidpf)png_ptr;
@@ -100,7 +101,8 @@ png_read_init(png_structp png_ptr)
 
    /* initialize zbuf - compression buffer */
    png_ptr->zbuf_size = PNG_ZBUF_SIZE;
-   png_ptr->zbuf = png_malloc(png_ptr, png_ptr->zbuf_size);
+   png_ptr->zbuf = (png_bytep)png_malloc(png_ptr,
+     (png_uint_32)png_ptr->zbuf_size);
    png_ptr->zstream.zalloc = png_zalloc;
    png_ptr->zstream.zfree = png_zfree;
    png_ptr->zstream.opaque = (voidpf)png_ptr;
@@ -407,14 +409,17 @@ png_read_row(png_structp png_ptr, png_bytep row, png_bytep dsp_row)
    png_ptr->row_info.channels = png_ptr->channels;
    png_ptr->row_info.bit_depth = png_ptr->bit_depth;
    png_ptr->row_info.pixel_depth = png_ptr->pixel_depth;
-   png_ptr->row_info.rowbytes = ((png_ptr->row_info.width *
-      (png_uint_32)png_ptr->row_info.pixel_depth + 7) >> 3);
+   {
+      png_ptr->row_info.rowbytes = ((png_ptr->row_info.width *
+         (png_uint_32)png_ptr->row_info.pixel_depth + 7) >> 3);
+   }
 
    png_read_filter_row(png_ptr, &(png_ptr->row_info),
       png_ptr->row_buf + 1, png_ptr->prev_row + 1,
       (int)(png_ptr->row_buf[0]));
 
-   png_memcpy(png_ptr->prev_row, png_ptr->row_buf, png_ptr->rowbytes + 1);
+   png_memcpy_check(png_ptr, png_ptr->prev_row, png_ptr->row_buf,
+      png_ptr->rowbytes + 1);
 
    if (png_ptr->transformations)
       png_do_read_transformations(png_ptr);
@@ -665,7 +670,7 @@ png_destroy_read_struct(png_structpp png_ptr_ptr, png_infopp info_ptr_ptr,
    if (end_info_ptr != NULL)
    {
 #if defined(PNG_READ_tEXt_SUPPORTED) || defined(PNG_READ_zTXt_SUPPORTED)
-      png_free(png_ptr, info_ptr->text);
+      png_free(png_ptr, end_info_ptr->text);
 #endif
       png_destroy_struct((png_voidp)end_info_ptr);
       *end_info_ptr_ptr = (png_infop)NULL;
@@ -710,7 +715,7 @@ png_read_destroy(png_structp png_ptr, png_infop info_ptr, png_infop end_info_ptr
    png_free(png_ptr, png_ptr->gamma_to_1);
 #endif
    if (png_ptr->flags & PNG_FLAG_FREE_PALETTE)
-      png_free(png_ptr, png_ptr->palette);
+      png_zfree(png_ptr, png_ptr->palette);
 #if defined(PNG_READ_BACKGROUND_SUPPORTED) && defined(PNG_READ_bKGD_SUPPORTED)
    if (png_ptr->flags & PNG_FLAG_FREE_TRANS)
       png_free(png_ptr, png_ptr->trans);

pngrio.c

@@ -1,12 +1,12 @@
 
 /* pngrio.c - functions for data input
  *
- * libpng 0.98
+ * libpng 0.99e
  * For conditions of distribution and use, see copyright notice in png.h
  * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
  * Copyright (c) 1996, 1997 Andreas Dilger
  * Copyright (c) 1998, Glenn Randers-Pehrson
- * January 16, 1998
+ * February 28, 1998
  *
  * This file provides a location for all input.  Users which need
  * special handling are expected to write a function which has the same
@@ -99,7 +99,7 @@ png_default_read_data(png_structp png_ptr, png_bytep data, png_size_t length)
       }
       while (remaining != 0);
    }
-   if (check != length)
+   if ((png_uint_32)check != (png_uint_32)length)
    {
       png_error(png_ptr, "read Error");
    }

pngrtran.c

@@ -1,12 +1,12 @@
 
 /* pngrtran.c - transforms the data in a row for PNG readers
  *
- * libpng 0.98
+ * libpng 0.99e
  * For conditions of distribution and use, see copyright notice in png.h
  * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
  * Copyright (c) 1996, 1997 Andreas Dilger
  * Copyright (c) 1998, Glenn Randers-Pehrson
- * January 16, 1998
+ * February 28, 1998
  *
  * This file contains functions optionally called by an application 
  * in order to tell libpng how to handle data when reading a PNG.
@@ -184,7 +184,7 @@ png_set_dither(png_structp png_ptr, png_colorp palette,
       int i;
 
       png_ptr->dither_index = (png_bytep)png_malloc(png_ptr,
-         num_palette * sizeof (png_byte));
+         (png_uint_32)(num_palette * sizeof (png_byte)));
       for (i = 0; i < num_palette; i++)
          png_ptr->dither_index[i] = (png_byte)i;
    }
@@ -200,7 +200,8 @@ png_set_dither(png_structp png_ptr, png_colorp palette,
          png_bytep sort;
 
          /* initialize an array to sort colors */
-         sort = (png_bytep)png_malloc(png_ptr, num_palette * sizeof (png_byte));
+         sort = (png_bytep)png_malloc(png_ptr, (png_uint_32)(num_palette
+            * sizeof (png_byte)));
 
          /* initialize the sort array */
          for (i = 0; i < num_palette; i++)
@@ -243,11 +244,11 @@ png_set_dither(png_structp png_ptr, png_colorp palette,
                move the others */
             for (i = 0, j = num_palette; i < maximum_colors; i++)
             {
-               if (sort[i] >= maximum_colors)
+               if ((int)sort[i] >= maximum_colors)
                {
                   do
                      j--;
-                  while (sort[j] >= maximum_colors);
+                  while ((int)sort[j] >= maximum_colors);
                   palette[i] = palette[j];
                }
             }
@@ -261,13 +262,13 @@ png_set_dither(png_structp png_ptr, png_colorp palette,
             for (i = 0, j = num_palette; i < maximum_colors; i++)
             {
                /* only move the colors we need to */
-               if (sort[i] >= maximum_colors)
+               if ((int)sort[i] >= maximum_colors)
                {
                   png_color tmp_color;
 
                   do
                      j--;
-                  while (sort[j] >= maximum_colors);
+                  while ((int)sort[j] >= maximum_colors);
 
                   tmp_color = palette[j];
                   palette[j] = palette[i];
@@ -281,7 +282,7 @@ png_set_dither(png_structp png_ptr, png_colorp palette,
             /* find closest color for those colors we are not using */
             for (i = 0; i < num_palette; i++)
             {
-               if (png_ptr->dither_index[i] >= maximum_colors)
+               if ((int)png_ptr->dither_index[i] >= maximum_colors)
                {
                   int min_d, k, min_k, d_index;
 
@@ -328,9 +329,9 @@ png_set_dither(png_structp png_ptr, png_colorp palette,
 
          /* initialize palette index arrays */
          index_to_palette = (png_bytep)png_malloc(png_ptr,
-            num_palette * sizeof (png_byte));
+            (png_uint_32)(num_palette * sizeof (png_byte)));
          palette_to_index = (png_bytep)png_malloc(png_ptr,
-            num_palette * sizeof (png_byte));
+            (png_uint_32)(num_palette * sizeof (png_byte)));
 
          /* initialize the sort array */
          for (i = 0; i < num_palette; i++)
@@ -339,7 +340,8 @@ png_set_dither(png_structp png_ptr, png_colorp palette,
             palette_to_index[i] = (png_byte)i;
          }
 
-         hash = (png_dsortpp)png_malloc(png_ptr, 769 * sizeof (png_dsortp));
+         hash = (png_dsortpp)png_malloc(png_ptr, (png_uint_32)(769 * 
+            sizeof (png_dsortp)));
          for (i = 0; i < 769; i++)
             hash[i] = NULL;
 /*         png_memset(hash, 0, 769 * sizeof (png_dsortp)); */
@@ -372,7 +374,8 @@ png_set_dither(png_structp png_ptr, png_colorp palette,
                   {
                      png_dsortp t;
 
-                     t = png_malloc(png_ptr, sizeof (png_dsort));
+                     t = (png_dsortp)png_malloc(png_ptr, (png_uint_32)(sizeof
+                         (png_dsort)));
                      t->next = hash[d];
                      t->left = (png_byte)i;
                      t->right = (png_byte)j;
@@ -389,8 +392,8 @@ png_set_dither(png_structp png_ptr, png_colorp palette,
 
                   for (p = hash[i]; p; p = p->next)
                   {
-                     if (index_to_palette[p->left] < num_new_palette &&
-                        index_to_palette[p->right] < num_new_palette)
+                     if ((int)index_to_palette[p->left] < num_new_palette &&
+                        (int)index_to_palette[p->right] < num_new_palette)
                      {
                         int j, next_j;
 
@@ -417,7 +420,7 @@ png_set_dither(png_structp png_ptr, png_colorp palette,
                                  index_to_palette[j])
                                  png_ptr->dither_index[k] =
                                     index_to_palette[next_j];
-                              if (png_ptr->dither_index[k] ==
+                              if ((int)png_ptr->dither_index[k] ==
                                  num_new_palette)
                                  png_ptr->dither_index[k] =
                                     index_to_palette[j];
@@ -488,11 +491,12 @@ png_set_dither(png_structp png_ptr, png_colorp palette,
       num_entries = ((png_size_t)1 << total_bits);
 
       png_ptr->palette_lookup = (png_bytep )png_malloc(png_ptr,
-         num_entries * sizeof (png_byte));
+         (png_uint_32)(num_entries * sizeof (png_byte)));
 
       png_memset(png_ptr->palette_lookup, 0, num_entries * sizeof (png_byte));
 
-      distance = (png_bytep)png_malloc(png_ptr, num_entries * sizeof(png_byte));
+      distance = (png_bytep)png_malloc(png_ptr, (png_uint_32)(num_entries *
+         sizeof(png_byte)));
 
       png_memset(distance, 0xff, num_entries * sizeof(png_byte));
 
@@ -527,7 +531,7 @@ png_set_dither(png_structp png_ptr, png_colorp palette,
                   dmax = ((dm > db) ? dm : db);
                   d = dmax + dt + db;
 
-                  if (d < distance[d_index])
+                  if (d < (int)distance[d_index])
                   {
                      distance[d_index] = (png_byte)d;
                      png_ptr->palette_lookup[d_index] = (png_byte)i;
@@ -656,7 +660,7 @@ png_init_read_transformations(png_structp png_ptr)
            /* invert the alpha channel (in tRNS) unless the pixels are 
               going to be expanded, in which case leave it for later */
               int i;
-              for (i=0; i<png_ptr->num_trans; i++)
+              for (i=0; i<(int)png_ptr->num_trans; i++)
                  png_ptr->trans[i] = 255 - png_ptr->trans[i];
            }
         }
@@ -767,8 +771,9 @@ png_init_read_transformations(png_structp png_ptr)
                }
             }
          }
-         else
          /* if (png_ptr->background_gamma_type!=PNG_BACKGROUND_GAMMA_UNKNOWN)*/
+         else
+         /* color_type != PNG_COLOR_TYPE_PALETTE */
          {
             double g, gs, m;
 
@@ -795,6 +800,7 @@ png_init_read_transformations(png_structp png_ptr)
 
             if (color_type & PNG_COLOR_MASK_COLOR)
             {
+               /* RGB or RGBA */
                png_ptr->background_1.red = (png_uint_16)(pow(
                   (double)png_ptr->background.red / m, g) * m + .5);
                png_ptr->background_1.green = (png_uint_16)(pow(
@@ -810,6 +816,7 @@ png_init_read_transformations(png_structp png_ptr)
             }
             else
             {
+               /* GRAY or GRAY ALPHA */
                png_ptr->background_1.gray = (png_uint_16)(pow(
                   (double)png_ptr->background.gray / m, g) * m + .5);
                png_ptr->background.gray = (png_uint_16)(pow(
@@ -818,6 +825,7 @@ png_init_read_transformations(png_structp png_ptr)
          }
       }
       else
+      /* transformation does not include PNG_BACKGROUND */
 #endif
       if (color_type == PNG_COLOR_TYPE_PALETTE)
       {
@@ -840,6 +848,7 @@ png_init_read_transformations(png_structp png_ptr)
 #endif
 #endif
 #if defined(PNG_READ_BACKGROUND_SUPPORTED)
+   /* No GAMMA transformation */
    if (png_ptr->transformations & PNG_BACKGROUND &&
        color_type == PNG_COLOR_TYPE_PALETTE)
    {
@@ -852,7 +861,7 @@ png_init_read_transformations(png_structp png_ptr)
       back.green = (png_byte)png_ptr->background.green;
       back.blue  = (png_byte)png_ptr->background.blue;
 
-      for (i = 0; i < png_ptr->num_trans; i++)
+      for (i = 0; i < (int)png_ptr->num_trans; i++)
       {
          if (png_ptr->trans[i] == 0)
          {
@@ -995,8 +1004,7 @@ png_read_transform_info(png_structp png_ptr, png_infop info_ptr)
    info_ptr->pixel_depth = (png_byte)(info_ptr->channels *
       info_ptr->bit_depth);
 
-   info_ptr->rowbytes = 
-      (png_size_t)((info_ptr->width * info_ptr->pixel_depth + 7) >> 3);
+   info_ptr->rowbytes = ((info_ptr->width * info_ptr->pixel_depth + 7) >> 3);
 }
 
 /* Transform the row.  The order of transformations is significant,
@@ -1085,6 +1093,8 @@ png_do_read_transformations(png_structp png_ptr)
    {
       png_do_dither((png_row_infop)&(png_ptr->row_info), png_ptr->row_buf + 1,
          png_ptr->palette_lookup, png_ptr->dither_index);
+      if(png_ptr->row_info.rowbytes == (png_uint_32)0)
+         png_error(png_ptr, "png_do_dither returned rowbytes=0");
    }
 #endif
 
@@ -1125,16 +1135,16 @@ png_do_read_transformations(png_structp png_ptr)
          (png_uint_32)png_ptr->filler, png_ptr->flags);
 #endif
 
-#if defined(PNG_READ_SWAP_ALPHA_SUPPORTED)
-   if (png_ptr->transformations & PNG_SWAP_ALPHA)
-      png_do_read_swap_alpha(&(png_ptr->row_info), png_ptr->row_buf + 1);
-#endif
-
 #if defined(PNG_READ_INVERT_ALPHA_SUPPORTED)
    if (png_ptr->transformations & PNG_INVERT_ALPHA)
       png_do_read_invert_alpha(&(png_ptr->row_info), png_ptr->row_buf + 1);
 #endif
 
+#if defined(PNG_READ_SWAP_ALPHA_SUPPORTED)
+   if (png_ptr->transformations & PNG_SWAP_ALPHA)
+      png_do_read_swap_alpha(&(png_ptr->row_info), png_ptr->row_buf + 1);
+#endif
+
 #if defined(PNG_READ_SWAP_SUPPORTED)
    if (png_ptr->transformations & PNG_SWAP_BYTES)
       png_do_swap(&(png_ptr->row_info), png_ptr->row_buf + 1);
@@ -1227,7 +1237,7 @@ png_do_unpack(png_row_infop row_info, png_bytep row)
       }
       row_info->bit_depth = 8;
       row_info->pixel_depth = (png_byte)(8 * row_info->channels);
-      row_info->rowbytes = (png_size_t)row_info->width * row_info->channels;
+      row_info->rowbytes = row_info->width * row_info->channels;
    }
 }
 #endif
@@ -1286,7 +1296,7 @@ png_do_unshift(png_row_infop row_info, png_bytep row, png_color_8p sig_bits)
          case 2:
          {
             png_bytep bp;
-            png_size_t i;
+            png_uint_32 i;
 
             for (bp = row, i = 0; i < row_info->rowbytes; i++, bp++)
             {
@@ -1299,7 +1309,7 @@ png_do_unshift(png_row_infop row_info, png_bytep row, png_color_8p sig_bits)
          {
             png_bytep bp;
             png_byte mask;
-            png_size_t i;
+            png_uint_32 i;
 
             mask = (png_byte)(((int)0xf0 >> shift[0]) & (int)0xf0) |
                (png_byte)((int)0xf >> shift[0]);
@@ -1313,11 +1323,11 @@ png_do_unshift(png_row_infop row_info, png_bytep row, png_color_8p sig_bits)
          case 8:
          {
             png_bytep bp;
-            png_size_t i;
+            png_uint_32 i;
 
             for (bp = row, i = 0; i < row_info->width; i++)
             {
-               for (c = 0; c < row_info->channels; c++, bp++)
+               for (c = 0; c < (int)row_info->channels; c++, bp++)
                {
                   *bp >>= shift[c];
                }
@@ -1331,7 +1341,7 @@ png_do_unshift(png_row_infop row_info, png_bytep row, png_color_8p sig_bits)
 
             for (bp = row, i = 0; i < row_info->width; i++)
             {
-               for (c = 0; c < row_info->channels; c++, bp += 2)
+               for (c = 0; c < (int)row_info->channels; c++, bp += 2)
                {
                   value = (png_uint_16)((*bp << 8) + *(bp + 1));
                   value >>= shift[c];
@@ -1395,7 +1405,7 @@ png_do_chop(png_row_infop row_info, png_bytep row)
       }
       row_info->bit_depth = 8;
       row_info->pixel_depth = (png_byte)(8 * row_info->channels);
-      row_info->rowbytes = (png_size_t)row_info->width * row_info->channels;
+      row_info->rowbytes = row_info->width * row_info->channels;
    }
 }
 #endif
@@ -1511,10 +1521,10 @@ png_do_read_invert_alpha(png_row_infop row_info, png_bytep row)
             for (i = 0, sp = dp = row + row_info->rowbytes;
                i < row_info->width; i++)
             {
-               *(--dp) = *(--sp);
-               *(--dp) = *(--sp);
-               *(--dp) = *(--sp);
                *(--dp) = 255 - *(--sp);
+               *(--dp) = *(--sp);
+               *(--dp) = *(--sp);
+               *(--dp) = *(--sp);
             }
          }
          /* This inverts the alpha channel in RRGGBBAA */
@@ -1526,20 +1536,20 @@ png_do_read_invert_alpha(png_row_infop row_info, png_bytep row)
             for (i = 0, sp = dp = row + row_info->rowbytes;
                i < row_info->width; i++)
             {
-               *(--dp) = *(--sp);
-               *(--dp) = *(--sp);
-               *(--dp) = *(--sp);
-               *(--dp) = *(--sp);
-               *(--dp) = *(--sp);
-               *(--dp) = *(--sp);
                *(--dp) = 255 - *(--sp);
                *(--dp) = 255 - *(--sp);
+               *(--dp) = *(--sp);
+               *(--dp) = *(--sp);
+               *(--dp) = *(--sp);
+               *(--dp) = *(--sp);
+               *(--dp) = *(--sp);
+               *(--dp) = *(--sp);
             }
          }
       }
       else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
       {
-         /* This inverts the alpha channel in AG */
+         /* This inverts the alpha channel in GA */
          if (row_info->bit_depth == 8)
          {
             png_bytep sp, dp;
@@ -1548,11 +1558,11 @@ png_do_read_invert_alpha(png_row_infop row_info, png_bytep row)
             for (i = 0, sp = dp = row + row_info->rowbytes;
                i < row_info->width; i++)
             {
-               *(--dp) = *(--sp);
                *(--dp) = 255 - *(--sp);
+               *(--dp) = *(--sp);
             }
          }
-         /* This inverts the alpha channel in AAGG */
+         /* This inverts the alpha channel in GGAA */
          else
          {
             png_bytep sp, dp;
@@ -1561,10 +1571,10 @@ png_do_read_invert_alpha(png_row_infop row_info, png_bytep row)
             for (i = 0, sp = dp = row + row_info->rowbytes;
                i < row_info->width; i++)
             {
-               *(--dp) = *(--sp);
-               *(--dp) = *(--sp);
                *(--dp) = 255 - *(--sp);
                *(--dp) = 255 - *(--sp);
+               *(--dp) = *(--sp);
+               *(--dp) = *(--sp);
             }
          }
       }
@@ -1604,7 +1614,7 @@ png_do_read_filler(png_row_infop row_info, png_bytep row,
          *(--dp) = (png_byte)filler;
          row_info->channels = 4;
          row_info->pixel_depth = 32;
-         row_info->rowbytes = (png_size_t)row_info->width * 4;
+         row_info->rowbytes = row_info->width * 4;
       }
       /* This changes the data from RGB to XRGB */
       else
@@ -1621,7 +1631,7 @@ png_do_read_filler(png_row_infop row_info, png_bytep row,
          }
          row_info->channels = 4;
          row_info->pixel_depth = 32;
-         row_info->rowbytes = (png_size_t)row_info->width * 4;
+         row_info->rowbytes = row_info->width * 4;
       }
    }
 }
@@ -1715,7 +1725,7 @@ png_do_gray_to_rgb(png_row_infop row_info, png_bytep row)
       row_info->color_type |= PNG_COLOR_MASK_COLOR;
       row_info->pixel_depth = (png_byte)(row_info->channels *
          row_info->bit_depth);
-      row_info->rowbytes = (png_size_t)((row_info->width *
+      row_info->rowbytes = ((row_info->width *
          row_info->pixel_depth + 7) >> 3);
    }
 }
@@ -1908,24 +1918,21 @@ png_correct_palette(png_structp png_ptr, png_colorp palette,
    {
       if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
       {
-         int i;
          png_color back;
 
          back.red   = (png_byte)png_ptr->background.red;
          back.green = (png_byte)png_ptr->background.green;
          back.blue  = (png_byte)png_ptr->background.blue;
 
-         for (i = 0; i < num_palette; i++)
+         for (i = 0; i < (int)png_ptr->num_trans; i++)
          {
-            if (i >= (int)png_ptr->num_trans ||
-               png_ptr->trans[i] == 0)
+            if (png_ptr->trans[i] == 0)
             {
                palette[i].red = back.red;
                palette[i].green = back.green;
                palette[i].blue = back.blue;
             }
-            else if (i < (int)png_ptr->num_trans ||
-               png_ptr->trans[i] != 0xff)
+            else if (png_ptr->trans[i] != 0xff)
             {
                png_composite(palette[i].red, png_ptr->palette[i].red,
                   png_ptr->trans[i], back.red);
@@ -1984,7 +1991,6 @@ png_do_background(png_row_infop row_info, png_bytep row,
       {
          case PNG_COLOR_TYPE_GRAY:
          {
-            /* We currently don't do gamma correction for 2 and 4 bit */
             switch (row_info->bit_depth)
             {
                case 1:
@@ -1993,7 +1999,8 @@ png_do_background(png_row_infop row_info, png_bytep row,
                   shift = 7;
                   for (i = 0; i < row_info->width; i++)
                   {
-                     if (((*sp >> shift) & 0x1) == trans_values->gray)
+                     if ((png_uint_16)((*sp >> shift) & 0x1)
+                        == trans_values->gray)
                      {
                         *sp &= (png_byte)((0x7f7f >> (7 - shift)) & 0xff);
                         *sp |= (png_byte)(background->gray << shift);
@@ -2014,7 +2021,8 @@ png_do_background(png_row_infop row_info, png_bytep row,
                   shift = 6;
                   for (i = 0; i < row_info->width; i++)
                   {
-                     if (((*sp >> shift) & 0x3) == trans_values->gray)
+                     if ((png_uint_16)((*sp >> shift) & 0x3)
+                         == trans_values->gray)
                      {
                         *sp &= (png_byte)((0x3f3f >> (6 - shift)) & 0xff);
                         *sp |= (png_byte)(background->gray << shift);
@@ -2035,7 +2043,8 @@ png_do_background(png_row_infop row_info, png_bytep row,
                   shift = 4;
                   for (i = 0; i < row_info->width; i++)
                   {
-                     if (((*sp >> shift) & 0xf) == trans_values->gray)
+                     if ((png_uint_16)((*sp >> shift) & 0xf)
+                         == trans_values->gray)
                      {
                         *sp &= (png_byte)((0xf0f >> (4 - shift)) & 0xff);
                         *sp |= (png_byte)(background->gray << shift);
@@ -2543,7 +2552,7 @@ png_do_background(png_row_infop row_info, png_bytep row,
          row_info->channels--;
          row_info->pixel_depth = (png_byte)(row_info->channels *
             row_info->bit_depth);
-         row_info->rowbytes = (png_size_t)((row_info->width *
+         row_info->rowbytes = ((row_info->width *
             row_info->pixel_depth + 7) >> 3);
       }
    }
@@ -2824,7 +2833,7 @@ png_do_expand_palette(png_row_infop row_info, png_bytep row,
          }
          row_info->bit_depth = 8;
          row_info->pixel_depth = 8;
-         row_info->rowbytes = (png_size_t)row_info->width;
+         row_info->rowbytes = row_info->width;
       }
       switch (row_info->bit_depth)
       {
@@ -2848,7 +2857,7 @@ png_do_expand_palette(png_row_infop row_info, png_bytep row,
                }
                row_info->bit_depth = 8;
                row_info->pixel_depth = 32;
-               row_info->rowbytes = (png_size_t)row_info->width * 4;
+               row_info->rowbytes = row_info->width * 4;
                row_info->color_type = 6;
                row_info->channels = 4;
             }
@@ -2866,7 +2875,7 @@ png_do_expand_palette(png_row_infop row_info, png_bytep row,
                }
                row_info->bit_depth = 8;
                row_info->pixel_depth = 24;
-               row_info->rowbytes = (png_size_t)row_info->width * 3;
+               row_info->rowbytes = row_info->width * 3;
                row_info->color_type = 2;
                row_info->channels = 3;
             }
@@ -2972,7 +2981,7 @@ png_do_expand(png_row_infop row_info, png_bytep row,
             }
             row_info->bit_depth = 8;
             row_info->pixel_depth = 8;
-            row_info->rowbytes = (png_size_t)row_info->width;
+            row_info->rowbytes = row_info->width;
          }
 
          if (trans_value != NULL)
@@ -3015,7 +3024,7 @@ png_do_expand(png_row_infop row_info, png_bytep row,
             row_info->channels = 2;
             row_info->pixel_depth = (png_byte)(row_info->bit_depth << 1);
             row_info->rowbytes =
-               (png_size_t)((row_info->width * row_info->pixel_depth) >> 3);
+               ((row_info->width * row_info->pixel_depth) >> 3);
          }
       }
       else if (row_info->color_type == PNG_COLOR_TYPE_RGB && trans_value)
@@ -3070,7 +3079,7 @@ png_do_expand(png_row_infop row_info, png_bytep row,
          row_info->channels = 4;
          row_info->pixel_depth = (png_byte)(row_info->bit_depth << 2);
          row_info->rowbytes =
-            (png_size_t)((row_info->width * row_info->pixel_depth) >> 3);
+            ((row_info->width * row_info->pixel_depth) >> 3);
       }
    }
 }
@@ -3123,7 +3132,7 @@ png_do_dither(png_row_infop row_info, png_bytep row,
          row_info->channels = 1;
          row_info->pixel_depth = row_info->bit_depth;
          row_info->rowbytes =
-            ((row_info->width * row_info->pixel_depth + 7) >> 3);
+             ((row_info->width * row_info->pixel_depth + 7) >> 3);
       }
       else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA &&
          palette_lookup != NULL && row_info->bit_depth == 8)
@@ -3153,7 +3162,7 @@ png_do_dither(png_row_infop row_info, png_bytep row,
          row_info->channels = 1;
          row_info->pixel_depth = row_info->bit_depth;
          row_info->rowbytes =
-            (png_size_t)((row_info->width * row_info->pixel_depth + 7) >> 3);
+            ((row_info->width * row_info->pixel_depth + 7) >> 3);
       }
       else if (row_info->color_type == PNG_COLOR_TYPE_PALETTE &&
          dither_lookup && row_info->bit_depth == 8)
@@ -3267,7 +3276,7 @@ png_build_gamma_table(png_structp png_ptr)
       g = 1.0 / (png_ptr->gamma * png_ptr->screen_gamma);
 
       png_ptr->gamma_16_table = (png_uint_16pp)png_malloc(png_ptr,
-         num * sizeof (png_uint_16p));
+         (png_uint_32)(num * sizeof (png_uint_16p)));
 
       if ((png_ptr->transformations & PNG_16_TO_8) &&
          !(png_ptr->transformations & PNG_BACKGROUND))
@@ -3278,7 +3287,7 @@ png_build_gamma_table(png_structp png_ptr)
          for (i = 0; i < num; i++)
          {
             png_ptr->gamma_16_table[i] = (png_uint_16p)png_malloc(png_ptr,
-               256 * sizeof (png_uint_16));
+               (png_uint_32)(256 * sizeof (png_uint_16)));
          }
 
          g = 1.0 / g;
@@ -3308,7 +3317,7 @@ png_build_gamma_table(png_structp png_ptr)
          for (i = 0; i < num; i++)
          {
             png_ptr->gamma_16_table[i] = (png_uint_16p)png_malloc(png_ptr,
-               256 * sizeof (png_uint_16));
+               (png_uint_32)(256 * sizeof (png_uint_16)));
 
             ig = (((png_uint_32)i * (png_uint_32)png_gamma_shift[shift]) >> 4);
             for (j = 0; j < 256; j++)
@@ -3326,12 +3335,12 @@ png_build_gamma_table(png_structp png_ptr)
          g = 1.0 / (png_ptr->gamma);
 
          png_ptr->gamma_16_to_1 = (png_uint_16pp)png_malloc(png_ptr,
-            num * sizeof (png_uint_16p ));
+            (png_uint_32)(num * sizeof (png_uint_16p )));
 
          for (i = 0; i < num; i++)
          {
             png_ptr->gamma_16_to_1[i] = (png_uint_16p)png_malloc(png_ptr,
-               256 * sizeof (png_uint_16));
+               (png_uint_32)(256 * sizeof (png_uint_16)));
 
             ig = (((png_uint_32)i *
                (png_uint_32)png_gamma_shift[shift]) >> 4);
@@ -3345,12 +3354,12 @@ png_build_gamma_table(png_structp png_ptr)
          g = 1.0 / (png_ptr->screen_gamma);
 
          png_ptr->gamma_16_from_1 = (png_uint_16pp)png_malloc(png_ptr,
-            num * sizeof (png_uint_16p));
+            (png_uint_32)(num * sizeof (png_uint_16p)));
 
          for (i = 0; i < num; i++)
          {
             png_ptr->gamma_16_from_1[i] = (png_uint_16p)png_malloc(png_ptr,
-               256 * sizeof (png_uint_16));
+               (png_uint_32)(256 * sizeof (png_uint_16)));
 
             ig = (((png_uint_32)i *
                (png_uint_32)png_gamma_shift[shift]) >> 4);

pngrutil.c

@@ -1,12 +1,12 @@
 
 /* pngrutil.c - utilities to read a PNG file
  *
- * libpng 0.98
+ * libpng 0.99
  * For conditions of distribution and use, see copyright notice in png.h
  * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
  * Copyright (c) 1996, 1997 Andreas Dilger
  * Copyright (c) 1998, Glenn Randers-Pehrson
- * January 16, 1998
+ * February 28, 1998
  *
  * This file contains routines which are only called from within
  * libpng itself during the course of reading an image.
@@ -27,7 +27,7 @@ png_get_uint_32(png_bytep buf)
       ((png_uint_32)(*(buf + 2)) << 8) +
       (png_uint_32)(*(buf + 3));
 
-   return i;
+   return (i);
 }
 
 #if defined(PNG_READ_pCAL_SUPPORTED)
@@ -44,7 +44,7 @@ png_get_int_32(png_bytep buf)
       ((png_int_32)(*(buf + 2)) << 8) +
       (png_int_32)(*(buf + 3));
 
-   return i;
+   return (i);
 }
 #endif /* PNG_READ_pCAL_SUPPORTED */
 
@@ -57,7 +57,7 @@ png_get_uint_16(png_bytep buf)
    i = (png_uint_16)(((png_uint_16)(*buf) << 8) +
       (png_uint_16)(*(buf + 1)));
 
-   return i;
+   return (i);
 }
 #endif /* PNG_READ_BIG_ENDIAN_SUPPORTED */
 
@@ -100,10 +100,10 @@ png_crc_finish(png_structp png_ptr, png_uint_32 skip)
       {
          png_chunk_error(png_ptr, "CRC error");
       }
-      return 1;
+      return (1);
    }
 
-   return 0;
+   return (0);
 }
 
 /* Compare the CRC stored in the PNG file with that calculated by libpng from
@@ -132,10 +132,10 @@ png_crc_error(png_structp png_ptr)
    if (need_crc)
    {
       crc = png_get_uint_32(crc_bytes);
-      return (crc != png_ptr->crc);
+      return ((int)(crc != png_ptr->crc));
    }
    else
-      return 0;
+      return (0);
 }
 
 
@@ -226,7 +226,7 @@ png_handle_IHDR(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
 
    /* set up other useful info */
    png_ptr->pixel_depth = (png_byte)(png_ptr->bit_depth *
-      png_ptr->channels);
+   png_ptr->channels);
    png_ptr->rowbytes = ((png_ptr->width *
       (png_uint_32)png_ptr->pixel_depth + 7) >> 3);
    png_debug1(3,"bit_depth = %d\n", png_ptr->bit_depth);
@@ -258,6 +258,20 @@ png_handle_PLTE(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
 
    png_ptr->mode |= PNG_HAVE_PLTE;
 
+#if defined (PNG_READ_tRNS_SUPPORTED)
+   if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+   {
+      if (info_ptr != NULL && info_ptr->valid & PNG_INFO_tRNS)
+      {
+         if (png_ptr->num_trans > png_ptr->num_palette)
+         {
+            png_warning(png_ptr, "Truncating incorrect tRNS chunk length");
+            png_ptr->num_trans = png_ptr->num_palette;
+         }
+      }
+   }
+#endif
+
 #if !defined(PNG_READ_OPT_PLTE_SUPPORTED)
    if (png_ptr->color_type != PNG_COLOR_TYPE_PALETTE)
    {
@@ -298,10 +312,13 @@ png_handle_PLTE(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
       whatever the normal CRC configuration tells us.  However, if we
       have an RGB image, the PLTE can be considered ancillary, so
       we will act as though it is. */
+#if !defined(PNG_READ_OPT_PLTE_SUPPORTED)
    if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+#endif
    {
       png_crc_finish(png_ptr, 0);
    }
+#if !defined(PNG_READ_OPT_PLTE_SUPPORTED)
    else if (png_crc_error(png_ptr))  /* Only if we have a CRC error */
    {
       /* If we don't want to use the data from an ancillary chunk,
@@ -328,7 +345,7 @@ png_handle_PLTE(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
          png_chunk_warning(png_ptr, "CRC error");
       }
    }
-
+#endif
    png_ptr->palette = palette;
    png_ptr->num_palette = (png_uint_16)num;
    png_set_PLTE(png_ptr, info_ptr, palette, num);
@@ -342,6 +359,10 @@ png_handle_IEND(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
    if (!(png_ptr->mode & PNG_HAVE_IHDR) || !(png_ptr->mode & PNG_HAVE_IDAT))
    {
       png_error(png_ptr, "No image in file");
+
+      /* to quiet compiler warnings about unused info_ptr */
+      if (info_ptr == NULL)
+         return;
    }
 
    png_ptr->mode |= PNG_AFTER_IDAT | PNG_HAVE_IEND;
@@ -404,7 +425,7 @@ png_handle_gAMA(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
 
 #if defined(PNG_READ_sRGB_SUPPORTED)
    if (info_ptr->valid & PNG_INFO_sRGB)
-      if(igamma != (png_uint_32)51000L)
+      if(igamma != (png_uint_32)45000L)
       {
          png_warning(png_ptr,
            "Ignoring incorrect gAMA value when sRGB is also present");
@@ -416,7 +437,9 @@ png_handle_gAMA(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
 #endif /* PNG_READ_sRGB_SUPPORTED */
 
    file_gamma = (float)igamma / (float)100000.0;
+#ifdef PNG_READ_GAMMA_SUPPORTED
    png_ptr->gamma = file_gamma;
+#endif
    png_set_gAMA(png_ptr, info_ptr, file_gamma);
 }
 #endif
@@ -663,15 +686,15 @@ png_handle_sRGB(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
 
    intent = buf[0];
    /* check for bad intent */
-   if (intent > 3)
+   if (intent >= PNG_sRGB_INTENT_LAST)
    {
       png_warning(png_ptr, "Unknown sRGB intent");
       return;
    }
 
-#ifdef PNG_READ_gAMA_SUPPORTED
+#if defined(PNG_READ_gAMA_SUPPORTED) && defined(PNG_READ_GAMMA_SUPPORTED)
    if ((info_ptr->valid & PNG_INFO_gAMA))
-      if((png_uint_32)(png_ptr->gamma*(float)100000.+.5) != (png_uint_32)51000L)
+      if((png_uint_32)(png_ptr->gamma*(float)100000.+.5) != (png_uint_32)45000L)
       {
          png_warning(png_ptr,
            "Ignoring incorrect gAMA value when sRGB is also present");
@@ -717,7 +740,7 @@ png_handle_tRNS(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
    }
    else if (info_ptr != NULL && info_ptr->valid & PNG_INFO_tRNS)
    {
-      png_warning(png_ptr, "Duplcate tRNS chunk");
+      png_warning(png_ptr, "Duplicate tRNS chunk");
       png_crc_finish(png_ptr, length);
       return;
    }
@@ -904,7 +927,7 @@ png_handle_hIST(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
 
    num = (int)length / 2;
    png_ptr->hist = (png_uint_16p)png_malloc(png_ptr,
-      num * sizeof (png_uint_16));
+      (png_uint_32)(num * sizeof (png_uint_16)));
    png_ptr->flags |= PNG_FLAG_FREE_HIST;
    for (i = 0; i < num; i++)
    {
@@ -1017,6 +1040,7 @@ png_handle_pCAL(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
    png_byte type, nparams;
    png_charp buf, units, endptr;
    png_charpp params;
+   png_size_t slength;
    int i;
 
    png_debug(1, "in png_handle_pCAL\n");
@@ -1039,7 +1063,8 @@ png_handle_pCAL(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
    png_debug1(2, "Allocating and reading pCAL chunk data (%d bytes)\n",
       length + 1);
    purpose = (png_charp)png_malloc(png_ptr, length + 1);
-   png_crc_read(png_ptr, (png_bytep)purpose, (png_size_t)length);
+   slength = (png_size_t)length;
+   png_crc_read(png_ptr, (png_bytep)purpose, slength);
 
    if (png_crc_finish(png_ptr, 0))
    {
@@ -1047,13 +1072,13 @@ png_handle_pCAL(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
       return;
    }
 
-   purpose[length] = '\0'; /* null terminate the last string */
+   purpose[slength] = 0x00; /* null terminate the last string */
 
    png_debug(3, "Finding end of pCAL purpose string\n");
    for (buf = purpose; *buf != '\0'; buf++)
       /* empty loop */;
 
-   endptr = purpose + length;
+   endptr = purpose + slength;
 
    /* We need to have at least 12 bytes after the purpose string
       in order to get the parameter information. */
@@ -1089,19 +1114,20 @@ png_handle_pCAL(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
    }
 
    /* Empty loop to move past the units string. */
-   for (buf = units; *buf != '\0'; buf++);
+   for (buf = units; *buf != 0x00; buf++);
 
    png_debug(3, "Allocating pCAL parameters array\n");
-   params = (png_charpp)png_malloc(png_ptr, nparams*sizeof(png_charp)) ;
+   params = (png_charpp)png_malloc(png_ptr, (png_uint_32)(nparams
+      *sizeof(png_charp))) ;
 
    /* Get pointers to the start of each parameter string. */
-   for (i = 0; i < nparams; i++)
+   for (i = 0; i < (int)nparams; i++)
    {
       buf++; /* Skip the null string terminator from previous parameter. */
 
       png_debug1(3, "Reading pCAL parameter %d\n", i);
       /* Empty loop to move past each paramter string */
-      for (params[i] = buf; *buf != '\0' && buf <= endptr; buf++);
+      for (params[i] = buf; *buf != 0x00 && buf <= endptr; buf++);
 
       /* Make sure we haven't run out of data yet */
       if (buf > endptr)
@@ -1173,6 +1199,7 @@ png_handle_tEXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
    png_charp key;
    png_charp text;
    png_uint_32 skip = 0;
+   png_size_t slength;
 
    png_debug(1, "in png_handle_tEXt\n");
 
@@ -1192,7 +1219,8 @@ png_handle_tEXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
 #endif
 
    key = (png_charp)png_malloc(png_ptr, length + 1);
-   png_crc_read(png_ptr, (png_bytep)key, (png_size_t)length);
+   slength = (png_size_t)length;
+   png_crc_read(png_ptr, (png_bytep)key, slength);
 
    if (png_crc_finish(png_ptr, skip))
    {
@@ -1200,15 +1228,15 @@ png_handle_tEXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
       return;
    }
 
-   key[length] = '\0';
+   key[slength] = 0x00;
 
    for (text = key; *text; text++)
       /* empty loop to find end of key */ ;
 
-   if (text != key + (png_size_t)length)
+   if (text != key + slength)
       text++;
 
-   text_ptr = (png_textp)png_malloc(png_ptr, sizeof(png_text));
+   text_ptr = (png_textp)png_malloc(png_ptr, (png_uint_32)sizeof(png_text));
    text_ptr->compression = PNG_TEXT_COMPRESSION_NONE;
    text_ptr->key = key;
    text_ptr->text = text;
@@ -1229,6 +1257,7 @@ png_handle_zTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
    png_charp key;
    png_charp text;
    int comp_type = PNG_TEXT_COMPRESSION_NONE;
+   png_size_t slength;
 
    png_debug(1, "in png_handle_zTXt\n");
 
@@ -1250,20 +1279,21 @@ png_handle_zTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
 #endif
 
    key = (png_charp)png_malloc(png_ptr, length + 1);
-   png_crc_read(png_ptr, (png_bytep)key, (png_size_t)length);
+   slength = (png_size_t)length;
+   png_crc_read(png_ptr, (png_bytep)key, slength);
    if (png_crc_finish(png_ptr, 0))
    {
       png_free(png_ptr, key);
       return;
    }
 
-   key[length] = '\0';
+   key[slength] = 0x00;
 
    for (text = key; *text; text++)
       /* empty loop */ ;
 
    /* zTXt must have some text after the keyword */
-   if (text == key + (png_size_t)length)
+   if (text == key + slength)
    {
       png_warning(png_ptr, "Zero length zTXt chunk");
    }
@@ -1277,7 +1307,7 @@ png_handle_zTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
       png_ptr->zstream.next_out = png_ptr->zbuf;
       png_ptr->zstream.avail_out = png_ptr->zbuf_size;
 
-      key_size = text - key;
+      key_size = (png_size_t)(text - key);
       text_size = 0;
       text = NULL;
 
@@ -1298,14 +1328,14 @@ png_handle_zTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
             if (text ==  NULL)
             {
                text_size = key_size + sizeof(msg) + 1;
-               text = (png_charp)png_malloc(png_ptr, text_size);
+               text = (png_charp)png_malloc(png_ptr, (png_uint_32)text_size);
                png_memcpy(text, key, key_size);
             }
 
-            text[text_size - 1] = '\0';
+            text[text_size - 1] = 0x00;
 
             /* Copy what we can of the error message into the text chunk */
-            text_size = length - (text - key) - 1;
+            text_size = (png_size_t)(slength - (text - key) - 1);
             text_size = sizeof(msg) > text_size ? text_size : sizeof(msg);
             png_memcpy(text + key_size, msg, text_size + 1);
             break;
@@ -1315,28 +1345,28 @@ png_handle_zTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
             if (text == NULL)
             {
                text = (png_charp)png_malloc(png_ptr,
-                  png_ptr->zbuf_size - png_ptr->zstream.avail_out +
-                     key_size + 1);
+                  (png_uint_32)(png_ptr->zbuf_size - png_ptr->zstream.avail_out
+                     + key_size + 1));
                png_memcpy(text + key_size, png_ptr->zbuf,
                   png_ptr->zbuf_size - png_ptr->zstream.avail_out);
                png_memcpy(text, key, key_size);
                text_size = key_size + png_ptr->zbuf_size -
                   png_ptr->zstream.avail_out;
-               *(text + text_size) = '\0';
+               *(text + text_size) = 0x00;
             }
             else
             {
                png_charp tmp;
 
                tmp = text;
-               text = png_malloc(png_ptr, text_size +
-                  png_ptr->zbuf_size - png_ptr->zstream.avail_out + 1);
+               text = (png_charp)png_malloc(png_ptr, (png_uint_32)(text_size +
+                  png_ptr->zbuf_size - png_ptr->zstream.avail_out + 1));
                png_memcpy(text, tmp, text_size);
                png_free(png_ptr, tmp);
                png_memcpy(text + text_size, png_ptr->zbuf,
                   (png_ptr->zbuf_size - png_ptr->zstream.avail_out));
                text_size += png_ptr->zbuf_size - png_ptr->zstream.avail_out;
-               *(text + text_size) = '\0';
+               *(text + text_size) = 0x00;
             }
             if (ret != Z_STREAM_END)
             {
@@ -1356,7 +1386,6 @@ png_handle_zTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
       png_free(png_ptr, key);
       key = text;
       text += key_size;
-      text_size -= key_size;
    }
    else /* if (comp_type >= PNG_TEXT_COMPRESSION_LAST) */
    {
@@ -1371,12 +1400,12 @@ png_handle_zTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
 #endif
 
       /* Copy what we can of the error message into the text chunk */
-      text_size = (png_size_t)length - (text - key) - 1;
+      text_size = (png_size_t)(slength - (text - key) - 1);
       text_size = sizeof(msg) > text_size ? text_size : sizeof(msg);
       png_memcpy(text, msg, text_size + 1);
    }
 
-   text_ptr = (png_textp)png_malloc(png_ptr, sizeof(png_text));
+   text_ptr = (png_textp)png_malloc(png_ptr, (png_uint_32)sizeof(png_text));
    text_ptr->compression = comp_type;
    text_ptr->key = key;
    text_ptr->text = text;
@@ -1404,12 +1433,17 @@ png_handle_unknown(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
    if (!(png_ptr->chunk_name[0] & 0x20))
    {
       png_chunk_error(png_ptr, "unknown critical chunk");
+
+      /* to quiet compiler warnings about unused info_ptr */
+      if (info_ptr == NULL)
+         return;
    }
 
    if (png_ptr->mode & PNG_HAVE_IDAT)
       png_ptr->mode |= PNG_AFTER_IDAT;
 
    png_crc_finish(png_ptr, length);
+
 }
 
 /* This function is called to verify that a chunk name is valid.
@@ -1842,8 +1876,8 @@ png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass,
 
             pixel_bytes = (row_info->pixel_depth >> 3);
 
-            sp = row + (row_info->width - 1) * pixel_bytes;
-            dp = row + (final_width - 1) * pixel_bytes;
+            sp = row + (png_size_t)(row_info->width - 1) * pixel_bytes;
+            dp = row + (png_size_t)(final_width - 1) * pixel_bytes;
             for (i = row_info->width; i; i--)
             {
                png_byte v[8];
@@ -1874,6 +1908,7 @@ png_read_filter_row(png_structp png_ptr, png_row_infop row_info, png_bytep row,
    png_debug(1, "in png_read_filter_row\n");
    png_debug2(2,"row = %d, filter = %d\n", png_ptr->row_number, filter);
 
+
    switch (filter)
    {
       case PNG_FILTER_VALUE_NONE:
@@ -1987,7 +2022,7 @@ png_read_finish_row(png_structp png_ptr)
    if (png_ptr->interlaced)
    {
       png_ptr->row_number = 0;
-      png_memset(png_ptr->prev_row, 0, png_ptr->rowbytes + 1);
+      png_memset_check(png_ptr, png_ptr->prev_row, 0, png_ptr->rowbytes + 1);
       do
       {
          png_ptr->pass++;
@@ -1997,8 +2032,9 @@ png_read_finish_row(png_structp png_ptr)
             png_pass_inc[png_ptr->pass] - 1 -
             png_pass_start[png_ptr->pass]) /
             png_pass_inc[png_ptr->pass];
-         png_ptr->irowbytes = ((png_ptr->iwidth *
-            png_ptr->pixel_depth + 7) >> 3) + 1;
+            png_ptr->irowbytes = ((png_ptr->iwidth *
+               (png_uint_32)png_ptr->pixel_depth + 7) >> 3) +1;
+
          if (!(png_ptr->transformations & PNG_INTERLACE))
          {
             png_ptr->num_rows = (png_ptr->height +
@@ -2099,8 +2135,12 @@ png_read_start_row(png_structp png_ptr)
          png_pass_inc[png_ptr->pass] - 1 -
          png_pass_start[png_ptr->pass]) /
          png_pass_inc[png_ptr->pass];
-      png_ptr->irowbytes = ((png_ptr->iwidth *
-         png_ptr->pixel_depth + 7) >> 3) + 1;
+
+         rowbytes = ((png_ptr->iwidth *
+            (png_uint_32)png_ptr->pixel_depth + 7) >> 3) +1;
+         png_ptr->irowbytes = (png_size_t)rowbytes;
+         if((png_uint_32)png_ptr->irowbytes != rowbytes)
+            png_error(png_ptr, "Rowbytes overflow in png_read_start_row");
    }
    else
    {
@@ -2189,9 +2229,10 @@ png_read_start_row(png_structp png_ptr)
    if ((png_uint_32)png_ptr->rowbytes + 1 > (png_uint_32)65536L)
       png_error(png_ptr, "This image requires a row greater than 64KB");
 #endif
-   png_ptr->prev_row = (png_bytep)png_malloc(png_ptr, png_ptr->rowbytes + 1);
+   png_ptr->prev_row = (png_bytep)png_malloc(png_ptr, (png_uint_32)(
+      png_ptr->rowbytes + 1));
 
-   png_memset(png_ptr->prev_row, 0, png_ptr->rowbytes + 1);
+   png_memset_check(png_ptr, png_ptr->prev_row, 0, png_ptr->rowbytes + 1);
 
    png_debug1(3, "width = %d,\n", png_ptr->width);
    png_debug1(3, "height = %d,\n", png_ptr->height);

pngset.c

@@ -1,12 +1,12 @@
 
 /* pngset.c - storage of image information into info struct
  *
- * libpng 0.98
+ * libpng 0.99e
  * For conditions of distribution and use, see copyright notice in png.h
  * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
  * Copyright (c) 1996, 1997 Andreas Dilger
  * Copyright (c) 1998, Glenn Randers-Pehrson
- * January 16, 1998
+ * February 28, 1998
  *
  * The functions here are used during reads to store data from the file
  * into the info struct, and during writes to store application data
@@ -22,7 +22,7 @@ void
 png_set_bKGD(png_structp png_ptr, png_infop info_ptr, png_color_16p background)
 {
    png_debug1(1, "in %s storage function\n", "bKGD");
-   if (info_ptr == NULL)
+   if (png_ptr == NULL || info_ptr == NULL)
       return;
 
    png_memcpy(&(info_ptr->background), background, sizeof(png_color_16));
@@ -37,7 +37,7 @@ png_set_cHRM(png_structp png_ptr, png_infop info_ptr,
    double green_x, double green_y, double blue_x, double blue_y)
 {
    png_debug1(1, "in %s storage function\n", "cHRM");
-   if (info_ptr == NULL)
+   if (png_ptr == NULL || info_ptr == NULL)
       return;
 
    info_ptr->x_white = (float)white_x;
@@ -57,7 +57,7 @@ void
 png_set_gAMA(png_structp png_ptr, png_infop info_ptr, double file_gamma)
 {
    png_debug1(1, "in %s storage function\n", "gAMA");
-   if (info_ptr == NULL)
+   if (png_ptr == NULL || info_ptr == NULL)
       return;
 
    info_ptr->gamma = (float)file_gamma;
@@ -70,7 +70,7 @@ void
 png_set_hIST(png_structp png_ptr, png_infop info_ptr, png_uint_16p hist)
 {
    png_debug1(1, "in %s storage function\n", "hIST");
-   if (info_ptr == NULL)
+   if (png_ptr == NULL || info_ptr == NULL)
       return;
 
    info_ptr->hist = hist;
@@ -84,8 +84,9 @@ png_set_IHDR(png_structp png_ptr, png_infop info_ptr,
    int color_type, int interlace_type, int compression_type,
    int filter_type)
 {
+   int rowbytes_per_pixel;
    png_debug1(1, "in %s storage function\n", "IHDR");
-   if (info_ptr == NULL)
+   if (png_ptr == NULL || info_ptr == NULL)
       return;
 
    info_ptr->width = width;
@@ -104,7 +105,16 @@ png_set_IHDR(png_structp png_ptr, png_infop info_ptr,
    if (info_ptr->color_type & PNG_COLOR_MASK_ALPHA)
       info_ptr->channels++;
    info_ptr->pixel_depth = (png_byte)(info_ptr->channels * info_ptr->bit_depth);
-   info_ptr->rowbytes = ((info_ptr->width * info_ptr->pixel_depth + 7) >> 3);
+
+   /* check for overflow */
+   rowbytes_per_pixel = (info_ptr->pixel_depth + 7) >> 3;
+   info_ptr->rowbytes = info_ptr->width * rowbytes_per_pixel;
+   if (( width > (png_uint_32)2147483647L/rowbytes_per_pixel))
+   {
+      png_warning(png_ptr,
+         "Width too large to process image data; rowbytes will overflow.");
+      info_ptr->rowbytes = (png_size_t)0;
+   }
 }
 
 #if defined(PNG_READ_oFFs_SUPPORTED) || defined(PNG_WRITE_oFFs_SUPPORTED)
@@ -113,7 +123,7 @@ png_set_oFFs(png_structp png_ptr, png_infop info_ptr,
    png_uint_32 offset_x, png_uint_32 offset_y, int unit_type)
 {
    png_debug1(1, "in %s storage function\n", "oFFs");
-   if (info_ptr == NULL)
+   if (png_ptr == NULL || info_ptr == NULL)
       return;
 
    info_ptr->x_offset = offset_x;
@@ -129,17 +139,17 @@ png_set_pCAL(png_structp png_ptr, png_infop info_ptr,
    png_charp purpose, png_int_32 X0, png_int_32 X1, int type, int nparams,
    png_charp units, png_charpp params)
 {
-   png_size_t length;
+   png_uint_32 length;
    int i;
 
    png_debug1(1, "in %s storage function\n", "pCAL");
-   if (info_ptr == NULL)
+   if (png_ptr == NULL || info_ptr == NULL)
       return;
 
    length = png_strlen(purpose) + 1;
    png_debug1(3, "allocating purpose for info (%d bytes)\n", length);
    info_ptr->pcal_purpose = (png_charp)png_malloc(png_ptr, length);
-   png_memcpy(info_ptr->pcal_purpose, purpose, length);
+   png_memcpy(info_ptr->pcal_purpose, purpose, (png_size_t)length);
 
    png_debug(3, "storing X0, X1, type, and nparams in info\n");
    info_ptr->pcal_X0 = X0;
@@ -150,10 +160,10 @@ png_set_pCAL(png_structp png_ptr, png_infop info_ptr,
    length = png_strlen(units) + 1;
    png_debug1(3, "allocating units for info (%d bytes)\n", length);
    info_ptr->pcal_units = (png_charp)png_malloc(png_ptr, length);
-   png_memcpy(info_ptr->pcal_units, units, length);
+   png_memcpy(info_ptr->pcal_units, units, (png_size_t)length);
 
    info_ptr->pcal_params = (png_charpp)png_malloc(png_ptr,
-      (nparams + 1) * sizeof(png_charp));
+      (png_uint_32)((nparams + 1) * sizeof(png_charp)));
    info_ptr->pcal_params[nparams] = NULL;
 
    for (i = 0; i < nparams; i++)
@@ -161,7 +171,7 @@ png_set_pCAL(png_structp png_ptr, png_infop info_ptr,
       length = png_strlen(params[i]) + 1;
       png_debug2(3, "allocating parameter %d for info (%d bytes)\n", i, length);
       info_ptr->pcal_params[i] = (png_charp)png_malloc(png_ptr, length);
-      png_memcpy(info_ptr->pcal_params[i], params[i], length);
+      png_memcpy(info_ptr->pcal_params[i], params[i], (png_size_t)length);
    }
 
    info_ptr->valid |= PNG_INFO_pCAL;
@@ -174,7 +184,7 @@ png_set_pHYs(png_structp png_ptr, png_infop info_ptr,
    png_uint_32 res_x, png_uint_32 res_y, int unit_type)
 {
    png_debug1(1, "in %s storage function\n", "pHYs");
-   if (info_ptr == NULL)
+   if (png_ptr == NULL || info_ptr == NULL)
       return;
 
    info_ptr->x_pixels_per_unit = res_x;
@@ -189,7 +199,7 @@ png_set_PLTE(png_structp png_ptr, png_infop info_ptr,
    png_colorp palette, int num_palette)
 {
    png_debug1(1, "in %s storage function\n", "PLTE");
-   if (info_ptr == NULL)
+   if (png_ptr == NULL || info_ptr == NULL)
       return;
 
    info_ptr->palette = palette;
@@ -203,7 +213,7 @@ png_set_sBIT(png_structp png_ptr, png_infop info_ptr,
    png_color_8p sig_bit)
 {
    png_debug1(1, "in %s storage function\n", "sBIT");
-   if (info_ptr == NULL)
+   if (png_ptr == NULL || info_ptr == NULL)
       return;
 
    png_memcpy(&(info_ptr->sig_bit), sig_bit, sizeof (png_color_8));
@@ -216,7 +226,7 @@ void
 png_set_sRGB(png_structp png_ptr, png_infop info_ptr, int intent)
 {
    png_debug1(1, "in %s storage function\n", "sRGB");
-   if (info_ptr == NULL)
+   if (png_ptr == NULL || info_ptr == NULL)
       return;
 
    info_ptr->srgb_intent = (png_byte)intent;
@@ -233,13 +243,13 @@ png_set_sRGB_gAMA_and_cHRM(png_structp png_ptr, png_infop info_ptr,
    float white_x, white_y, red_x, red_y, green_x, green_y, blue_x, blue_y;
 #endif
    png_debug1(1, "in %s storage function\n", "sRGB_gAMA_and_cHRM");
-   if (info_ptr == NULL)
+   if (png_ptr == NULL || info_ptr == NULL)
       return;
 
    png_set_sRGB(png_ptr, info_ptr, intent);
 
 #if defined(PNG_READ_gAMA_SUPPORTED) || defined(PNG_WRITE_gAMA_SUPPORTED)
-   file_gamma = (float).51;
+   file_gamma = (float).45;
    png_set_gAMA(png_ptr, info_ptr, file_gamma);
 #endif
 
@@ -271,7 +281,7 @@ png_set_text(png_structp png_ptr, png_infop info_ptr, png_textp text_ptr,
    png_debug1(1, "in %s storage function\n", (png_ptr->chunk_name[0] == '\0' ?
       "text" : (png_const_charp)png_ptr->chunk_name));
 
-   if (info_ptr == NULL || num_text == 0)
+   if (png_ptr == NULL || info_ptr == NULL || num_text == 0)
       return;
 
    /* Make sure we have enough space in the "text" array in info_struct
@@ -288,8 +298,9 @@ png_set_text(png_structp png_ptr, png_infop info_ptr, png_textp text_ptr,
          info_ptr->max_text = info_ptr->num_text + num_text + 8;
          old_text = info_ptr->text;
          info_ptr->text = (png_textp)png_malloc(png_ptr,
-            info_ptr->max_text * sizeof (png_text));
-         png_memcpy(info_ptr->text, old_text, old_max * sizeof(png_text));
+            (png_uint_32)(info_ptr->max_text * sizeof (png_text)));
+         png_memcpy(info_ptr->text, old_text, (png_size_t)(old_max *
+            sizeof(png_text)));
          png_free(png_ptr, old_text);
       }
       else
@@ -297,7 +308,7 @@ png_set_text(png_structp png_ptr, png_infop info_ptr, png_textp text_ptr,
          info_ptr->max_text = num_text + 8;
          info_ptr->num_text = 0;
          info_ptr->text = (png_textp)png_malloc(png_ptr,
-            info_ptr->max_text * sizeof (png_text));
+            (png_uint_32)(info_ptr->max_text * sizeof (png_text)));
       }
       png_debug1(3, "allocated %d entries for info_ptr->text\n",
          info_ptr->max_text);
@@ -333,7 +344,7 @@ void
 png_set_tIME(png_structp png_ptr, png_infop info_ptr, png_timep mod_time)
 {
    png_debug1(1, "in %s storage function\n", "tIME");
-   if (info_ptr == NULL)
+   if (png_ptr == NULL || info_ptr == NULL)
       return;
 
    png_memcpy(&(info_ptr->mod_time), mod_time, sizeof (png_time));
@@ -347,7 +358,7 @@ png_set_tRNS(png_structp png_ptr, png_infop info_ptr,
    png_bytep trans, int num_trans, png_color_16p trans_values)
 {
    png_debug1(1, "in %s storage function\n", "tRNS");
-   if (info_ptr == NULL)
+   if (png_ptr == NULL || info_ptr == NULL)
       return;
 
    if (trans != NULL)

pngtest.c

@@ -1,12 +1,12 @@
 
 /* pngtest.c - a simple test program to test libpng
  *
- * libpng 0.98
+ * libpng 0.99e
  * For conditions of distribution and use, see copyright notice in png.h
  * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
  * Copyright (c) 1996, 1997 Andreas Dilger
  * Copyright (c) 1998, Glenn Randers-Pehrson
- * January 16, 1998
+ * February 28, 1998
  *
  * This program reads in a PNG image, writes it out again, and then
  * compares the two files.  If the files are identical, this shows that
@@ -47,6 +47,9 @@ int test_one_file(PNG_CONST char *inname, PNG_CONST char *outname);
 /*  #define STDERR stderr  */
 #define STDERR stdout   /* for DOS */
 
+static int verbose = 0;
+static int wrote_question = 0;
+
 #if defined(PNG_NO_STDIO)
 /* START of code to validate stdio-free compilation */
 /* These copies of the default read/write functions come from pngrio.c and */
@@ -57,6 +60,8 @@ int test_one_file(PNG_CONST char *inname, PNG_CONST char *outname);
    than changing the library. */
 #ifndef USE_FAR_KEYWORD
 static void
+png_default_read_data(png_structp png_ptr, png_bytep data, png_size_t length);
+static void
 png_default_read_data(png_structp png_ptr, png_bytep data, png_size_t length)
 {
    png_size_t check;
@@ -81,6 +86,8 @@ png_default_read_data(png_structp png_ptr, png_bytep data, png_size_t length)
 #define NEAR_BUF_SIZE 1024
 #define MIN(a,b) (a <= b ? a : b)
  
+static void
+png_default_read_data(png_structp png_ptr, png_bytep data, png_size_t length);
 static void
 png_default_read_data(png_structp png_ptr, png_bytep data, png_size_t length)
 {
@@ -124,6 +131,8 @@ png_default_read_data(png_structp png_ptr, png_bytep data, png_size_t length)
 
 #if defined(PNG_WRITE_FLUSH_SUPPORTED)
 static void
+png_default_flush(png_structp png_ptr);
+static void
 png_default_flush(png_structp png_ptr)
 {
    FILE *io_ptr;
@@ -139,6 +148,8 @@ png_default_flush(png_structp png_ptr)
    than changing the library. */
 #ifndef USE_FAR_KEYWORD
 static void
+png_default_write_data(png_structp png_ptr, png_bytep data, png_size_t length);
+static void
 png_default_write_data(png_structp png_ptr, png_bytep data, png_size_t length)
 {
    png_uint_32 check;
@@ -158,6 +169,8 @@ png_default_write_data(png_structp png_ptr, png_bytep data, png_size_t length)
 #define NEAR_BUF_SIZE 1024
 #define MIN(a,b) (a <= b ? a : b)
 
+static void
+png_default_write_data(png_structp png_ptr, png_bytep data, png_size_t length);
 static void
 png_default_write_data(png_structp png_ptr, png_bytep data, png_size_t length)
 {
@@ -229,6 +242,107 @@ png_default_error(png_structp png_ptr, png_const_charp message)
 #endif /* PNG_NO_STDIO */
 /* END of code to validate stdio-free compilation */
 
+/* START of code to validate memory allocation and deallocation */
+#ifdef PNGTEST_MEMORY_DEBUG
+/* Borland DOS special memory handler */
+#if defined(__TURBOC__) && !defined(_Windows) && !defined(__FLAT__)
+ERROR - memory debugging is not supported on this platform
+#else
+
+/* Allocate memory.  For reasonable files, size should never exceed
+   64K.  However, zlib may allocate more then 64K if you don't tell
+   it not to.  See zconf.h and png.h for more information.  zlib does
+   need to allocate exactly 64K, so whatever you call here must
+   have the ability to do that.
+
+   This piece of code can be compiled to validate max 64K allocations
+   by setting MAXSEG_64K in zlib zconf.h *or* PNG_MAX_MALLOC_64K. */
+typedef struct memory_information {
+   png_uint_32                    size;
+   png_voidp                      pointer;
+   struct memory_information FAR *next;
+} memory_information;
+typedef memory_information FAR *memory_infop;
+
+static memory_infop pinformation = NULL;
+static int current_allocation = 0;
+static int maximum_allocation = 0;
+
+extern PNG_EXPORT(png_voidp,png_debug_malloc) PNGARG((png_structp png_ptr,
+   png_uint_32 size));
+extern PNG_EXPORT(void,png_debug_free) PNGARG((png_structp png_ptr,
+   png_voidp ptr));
+
+png_voidp
+png_malloc(png_structp png_ptr, png_uint_32 size) {
+   if (png_ptr == NULL) {
+      fprintf(STDERR, "NULL pointer to memory allocator\n");
+      return (NULL);
+   }
+   if (size == 0)
+      return (png_voidp)(NULL);
+
+   /* This calls the library allocator twice, once to get the requested
+      buffer and once to get a new free list entry. */
+   {
+      memory_infop pinfo = png_debug_malloc(png_ptr, sizeof *pinfo);
+      pinfo->size = size;
+      current_allocation += size;
+      if (current_allocation > maximum_allocation)
+         maximum_allocation = current_allocation;
+      pinfo->pointer = png_debug_malloc(png_ptr, size);
+      pinfo->next = pinformation;
+      pinformation = pinfo;
+      /* Make sure the caller isn't assuming zeroed memory. */
+      png_memset(pinfo->pointer, 0xdd, pinfo->size);
+      return (png_voidp)(pinfo->pointer);
+   }
+}
+
+/* Free a pointer.  It is removed from the list at the same time. */
+void
+png_free(png_structp png_ptr, png_voidp ptr)
+{
+   if (png_ptr == NULL)
+      fprintf(STDERR, "NULL pointer to memory allocator\n");
+   if (ptr == 0) {
+#if 0 /* This happens all the time. */
+      fprintf(STDERR, "WARNING: freeing NULL pointer\n");
+#endif
+      return;
+   }
+
+   /* Unlink the element from the list. */
+   {
+      memory_infop FAR *ppinfo = &pinformation;
+      for (;;) {
+         memory_infop pinfo = *ppinfo;
+         if (pinfo->pointer == ptr) {
+            *ppinfo = pinfo->next;
+            current_allocation -= pinfo->size;
+            if (current_allocation < 0)
+               fprintf(STDERR, "Duplicate free of memory\n");
+            /* We must free the list element too, but first kill
+               the memory which is to be freed. */
+            memset(ptr, 0x55, pinfo->size);
+            png_debug_free(png_ptr, pinfo);
+            break;
+         }
+         if (pinfo->next == NULL) {
+            fprintf(STDERR, "Pointer %x not found\n", ptr);
+            break;
+         }
+         ppinfo = &pinfo->next;
+      }
+   }
+
+   /* Finally free the data. */
+   png_debug_free(png_ptr, ptr);
+}
+#endif /* Not Borland DOS special memory handler */
+#endif
+/* END of code to test memory allocation/deallocation */
+
 /* Test one file */
 int test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
 {
@@ -251,14 +365,14 @@ int test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
    if ((fpin = fopen(inname, "rb")) == NULL)
    {
       fprintf(STDERR, "Could not find input file %s\n", inname);
-      return 1;
+      return (1);
    }
 
    if ((fpout = fopen(outname, "wb")) == NULL)
    {
       fprintf(STDERR, "Could not open output file %s\n", outname);
       fclose(fpin);
-      return 1;
+      return (1);
    }
 
    png_debug(0, "Allocating read and write structures\n");
@@ -291,7 +405,7 @@ int test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
       png_destroy_write_struct(&write_ptr, &write_info_ptr);
       fclose(fpin);
       fclose(fpout);
-      return 1;
+      return (1);
    }
 
    png_debug(0, "Setting jmpbuf for write struct\n");
@@ -307,7 +421,7 @@ int test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
       png_destroy_write_struct(&write_ptr, &write_info_ptr);
       fclose(fpin);
       fclose(fpout);
-      return 1;
+      return (1);
    }
 
 #ifdef USE_FAR_KEYWORD
@@ -338,7 +452,11 @@ int test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
           &color_type, &interlace_type, &compression_type, &filter_type))
       {
          png_set_IHDR(write_ptr, write_info_ptr, width, height, bit_depth,
+#if defined(PNG_WRITE_INTERLACING_SUPPORTED)
             color_type, interlace_type, compression_type, filter_type);
+#else
+            color_type, PNG_INTERLACE_NONE, compression_type, filter_type);
+#endif
       }
    }
 #if defined(PNG_READ_bKGD_SUPPORTED) && defined(PNG_WRITE_bKGD_SUPPORTED)
@@ -490,6 +608,7 @@ int test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
    png_debug(0, "\nWriting info struct\n");
    png_write_info(write_ptr, write_info_ptr);
 
+   png_debug(0, "\nAllocating row buffer \n");
    row_buf = (png_bytep)png_malloc(read_ptr, 
       png_get_rowbytes(read_ptr, read_info_ptr));
    if (row_buf == NULL)
@@ -499,14 +618,16 @@ int test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
       png_destroy_write_struct(&write_ptr, &write_info_ptr);
       fclose(fpin);
       fclose(fpout);
-      return 1;
+      return (1);
    }
+   png_debug(0, "Writing row data\n");
 
    num_pass = png_set_interlace_handling(read_ptr);
    png_set_interlace_handling(write_ptr);
 
    for (pass = 0; pass < num_pass; pass++)
    {
+      png_debug1(0, "Writing row data for pass %d\n",pass);
       for (y = 0; y < height; y++)
       {
          png_read_rows(read_ptr, (png_bytepp)&row_buf, (png_bytepp)NULL, 1);
@@ -517,6 +638,17 @@ int test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
    png_debug(0, "Reading and writing end_info data\n");
    png_read_end(read_ptr, end_info_ptr);
    png_write_end(write_ptr, end_info_ptr);
+ 
+#ifdef PNG_EASY_ACCESS_SUPPORTED
+   if(verbose)
+   {
+      png_uint_32 iwidth, iheight;
+      iwidth = png_get_image_width(write_ptr, write_info_ptr);
+      iheight = png_get_image_height(write_ptr, write_info_ptr);
+      fprintf(STDERR, "Image width = %lu, height = %lu\n",
+         iwidth, iheight);
+   }
+#endif
 
    png_debug(0, "Destroying data structs\n");
    png_free(read_ptr, row_buf);
@@ -530,14 +662,14 @@ int test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
    if ((fpin = fopen(inname, "rb")) == NULL)
    {
       fprintf(STDERR, "Could not find file %s\n", inname);
-      return 1;
+      return (1);
    }
 
    if ((fpout = fopen(outname, "rb")) == NULL)
    {
       fprintf(STDERR, "Could not find file %s\n", outname);
       fclose(fpin);
-      return 1;
+      return (1);
    }
 
    while (1)
@@ -551,9 +683,20 @@ int test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
       {
          fprintf(STDERR, "Files %s and %s are of a different size\n",
                  inname, outname);
+         if(wrote_question == 0)
+         {
+            fprintf(STDERR,
+              "   Was %s written with the same chunk size (8k),",inname);
+            fprintf(STDERR,
+              " filtering\n   heuristic (libpng default), compression");
+            fprintf(STDERR,
+              " level (zlib default)\n   and zlib version (%s)?\n\n",
+              ZLIB_VERSION);
+            wrote_question=1;
+         }
          fclose(fpin);
          fclose(fpout);
-         return 1;
+         return (0);
       }
 
       if (!num_in)
@@ -562,16 +705,27 @@ int test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
       if (png_memcmp(inbuf, outbuf, num_in))
       {
          fprintf(STDERR, "Files %s and %s are different\n", inname, outname);
+         if(wrote_question == 0)
+         {
+            fprintf(STDERR,
+              "   Was %s written with the same chunk size (8k),",inname);
+            fprintf(STDERR,
+              " filtering\n   heuristic (libpng default), compression");
+            fprintf(STDERR,
+              " level (zlib default)\n   and zlib version (%s)?\n\n",
+              ZLIB_VERSION);
+            wrote_question=1;
+         }
          fclose(fpin);
          fclose(fpout);
-         return 1;
+         return (0);
       }
    }
 
    fclose(fpin);
    fclose(fpout);
 
-   return 0;
+   return (0);
 }
 
 /* input and output filenames */
@@ -590,6 +744,19 @@ main(int argc, char *argv[])
    int ierror = 0;
 
    fprintf(STDERR, "Testing libpng version %s\n", PNG_LIBPNG_VER_STRING);
+   fprintf(STDERR, "   with zlib   version %s\n", ZLIB_VERSION);
+
+   /* Do some consistency checking on the memory allocation settings, I'm
+      not sure this matters, but it is nice to know, the first of these
+      tests should be impossible because of the way the macros are set
+      in pngconf.h */
+   #if defined(MAXSEG_64K) && !defined(PNG_MAX_MALLOC_64K)
+      fprintf(STDERR, " NOTE: Zlib compiled for max 64k, libpng not\n");
+   #endif
+   /* I think the following can happen. */
+   #if !defined(MAXSEG_64K) && defined(PNG_MAX_MALLOC_64K)
+      fprintf(STDERR, " NOTE: libpng compiled for max 64k, zlib not\n");
+   #endif
 
    if (strcmp(png_libpng_ver, PNG_LIBPNG_VER_STRING))
    {
@@ -602,16 +769,27 @@ main(int argc, char *argv[])
 
    if (argc > 1)
    {
-   if (strcmp(argv[1], "-m") == 0)
-      multiple = 1;
-   else
-      inname = argv[1];
+      if (strcmp(argv[1], "-m") == 0)
+         multiple = 1;
+      else if (strcmp(argv[1], "-mv") == 0 ||
+               strcmp(argv[1], "-vm") == 0 )
+      {
+         multiple = 1;
+         verbose = 1;
+      }
+      else if (strcmp(argv[1], "-v") == 0)
+      {
+         verbose = 1;
+         inname = argv[2];
+      }
+      else
+         inname = argv[1];
    }
 
-   if (!multiple && argc == 3)
-     outname = argv[2];
+   if (!multiple && argc == 3+verbose)
+     outname = argv[2+verbose];
 
-   if ((!multiple && argc > 3) || (multiple && argc < 2))
+   if ((!multiple && argc > 3+verbose) || (multiple && argc < 2))
    {
      fprintf(STDERR,
        "usage: %s [infile.png] [outfile.png]\n\t%s -m {infile.png}\n",
@@ -626,36 +804,88 @@ main(int argc, char *argv[])
    if (multiple)
    {
       int i;
+#ifdef PNGTEST_MEMORY_DEBUG
+      int allocation_now = current_allocation;
+#endif
       for (i=2; i<argc; ++i)
-         {
+      {
          int kerror;
          fprintf(STDERR, "Testing %s:",argv[i]);
          kerror = test_one_file(argv[i], outname);
-         if (kerror == 0) fprintf(STDERR, " PASS\n");
+         if (kerror == 0) 
+            fprintf(STDERR, " PASS\n");
          else {
             fprintf(STDERR, " FAIL\n");
             ierror += kerror;
             }
+#ifdef PNGTEST_MEMORY_DEBUG
+         if (allocation_now != current_allocation)
+            fprintf(STDERR, "MEMORY ERROR: %d bytes lost\n",
+               current_allocation-allocation_now);
+         if (current_allocation != 0) {
+            memory_infop pinfo = pinformation;
+
+            fprintf(STDERR, "MEMORY ERROR: %d bytes still allocated\n",
+               current_allocation);
+            while (pinfo != NULL) {
+               fprintf(STDERR, " %d bytes at %x\n", pinfo->size, pinfo->pointer);
+               pinfo = pinfo->next;
+               }
          }
+#endif
+      }
+#ifdef PNGTEST_MEMORY_DEBUG
+         fprintf(STDERR, "Maximum memory allocation: %d bytes\n",
+            maximum_allocation);
+#endif
    }
    else
    {
       int i;
       for (i=0; i<3; ++i) {
          int kerror;
-         fprintf(STDERR, "Testing %s:",inname);
+#ifdef PNGTEST_MEMORY_DEBUG
+         int allocation_now = current_allocation;
+#endif
+         if (i == 0 || verbose == 1 || ierror != 0)
+            fprintf(STDERR, "Testing %s:",inname);
          kerror = test_one_file(inname, outname);
-         if (kerror == 0) fprintf(STDERR, " PASS\n");
-         else {
+         if(kerror == 0)
+         {
+            if(verbose == 1 || i == 2) fprintf(STDERR, " PASS\n");
+         }
+         else
+         {
+            if(verbose == 0 && i != 2)
+               fprintf(STDERR, "Testing %s:",inname);
             fprintf(STDERR, " FAIL\n");
             ierror += kerror;
-            }
+         }
+#ifdef PNGTEST_MEMORY_DEBUG
+         if (allocation_now != current_allocation)
+             fprintf(STDERR, "MEMORY ERROR: %d bytes lost\n",
+               current_allocation-allocation_now);
+         if (current_allocation != 0) {
+             memory_infop pinfo = pinformation;
+   
+             fprintf(STDERR, "MEMORY ERROR: %d bytes still allocated\n",
+                current_allocation);
+             while (pinfo != NULL) {
+                fprintf(STDERR, " %d bytes at %x\n", pinfo->size, pinfo->pointer);
+                pinfo = pinfo->next;
+             }
+          }
+#endif
        }
+#ifdef PNGTEST_MEMORY_DEBUG
+       fprintf(STDERR, "Maximum memory allocation: %d bytes\n",
+          maximum_allocation);
+#endif
    }
 
    if (ierror == 0)
       fprintf(STDERR, "libpng passes test\n");
    else
       fprintf(STDERR, "libpng FAILS test\n");
-   return ierror != 0;
+   return (int)(ierror != 0);
 }

pngtrans.c

@@ -1,12 +1,12 @@
 
 /* pngtrans.c - transforms the data in a row (used by both readers and writers)
  *
- * libpng 0.98
+ * libpng 0.99e
  * For conditions of distribution and use, see copyright notice in png.h
  * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
  * Copyright (c) 1996, 1997 Andreas Dilger
  * Copyright (c) 1998, Glenn Randers-Pehrson
- * January 16, 1998
+ * February 28, 1998
  */
 
 #define PNG_INTERNAL
@@ -68,7 +68,8 @@ png_set_shift(png_structp png_ptr, png_color_8p true_bits)
 }
 #endif
 
-#if defined(PNG_READ_INTERLACING_SUPPORTED) || defined(PNG_WRITE_INTERLACING_SUPPORTED)
+#if defined(PNG_READ_INTERLACING_SUPPORTED) || \
+    defined(PNG_WRITE_INTERLACING_SUPPORTED)
 int
 png_set_interlace_handling(png_structp png_ptr)
 {
@@ -76,10 +77,10 @@ png_set_interlace_handling(png_structp png_ptr)
    if (png_ptr->interlaced)
    {
       png_ptr->transformations |= PNG_INTERLACE;
-      return 7;
+      return (7);
    }
 
-   return 1;
+   return (1);
 }
 #endif
 
@@ -299,7 +300,7 @@ png_do_packswap(png_row_infop row_info, png_bytep row)
    png_debug(1, "in png_do_packswap\n");
    if (
 #if defined(PNG_USELESS_TESTS_SUPPORTED)
-       row != NULL && row_info != NULL
+       row != NULL && row_info != NULL &&
 #endif
        row_info->bit_depth < 8)
    {

pngwio.c

@@ -1,12 +1,12 @@
 
 /* pngwio.c - functions for data output
  *
- * libpng 0.98
+ * libpng 0.99e
  * For conditions of distribution and use, see copyright notice in png.h
  * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
  * Copyright (c) 1996, 1997 Andreas Dilger
  * Copyright (c) 1998, Glenn Randers-Pehrson
- * January 16, 1998
+ * February 28, 1998
  *
  * This file provides a location for all output.  Users which need
  * special handling are expected to write functions which have the same
@@ -180,7 +180,7 @@ png_set_write_fn(png_structp png_ptr, png_voidp io_ptr,
 
 #if defined(USE_FAR_KEYWORD) 
 #if defined(_MSC_VER)   
-void *far_to_near(png_structp png_ptr,png_voidp ptr, int check)
+void *png_far_to_near(png_structp png_ptr,png_voidp ptr, int check)
 {
    void *near_ptr;   
    void FAR *far_ptr;
@@ -192,7 +192,7 @@ void *far_to_near(png_structp png_ptr,png_voidp ptr, int check)
    return(near_ptr);
 }
 #  else
-void *far_to_near(png_structp png_ptr,png_voidp ptr, int check)
+void *png_far_to_near(png_structp png_ptr,png_voidp ptr, int check)
 {
    void *near_ptr;   
    void FAR *far_ptr;

pngwrite.c

@@ -1,12 +1,12 @@
    
 /* pngwrite.c - general routines to write a PNG file
  *
- * libpng 0.98
+ * libpng 0.99e
  * For conditions of distribution and use, see copyright notice in png.h
  * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
  * Copyright (c) 1996, 1997 Andreas Dilger
  * Copyright (c) 1998, Glenn Randers-Pehrson
- * January 16, 1998
+ * February 28, 1998
  */
 
 /* get internal access to png.h */
@@ -34,7 +34,12 @@ png_write_info(png_structp png_ptr, png_infop info_ptr)
    /* write IHDR information. */
    png_write_IHDR(png_ptr, info_ptr->width, info_ptr->height,
       info_ptr->bit_depth, info_ptr->color_type, info_ptr->compression_type,
-      info_ptr->filter_type, info_ptr->interlace_type);
+      info_ptr->filter_type,
+#if defined(PNG_WRITE_INTERLACING_SUPPORTED)
+      info_ptr->interlace_type);
+#else
+      0);
+#endif
    /* the rest of these check to see if the valid field has the appropriate
       flag set, and if it does, writes the chunk. */
 #if defined(PNG_WRITE_gAMA_SUPPORTED)
@@ -71,9 +76,9 @@ png_write_info(png_structp png_ptr, png_infop info_ptr)
          if (png_ptr->transformations & PNG_INVERT_ALPHA &&
             info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
          {
-            int i;
-            for (i=0; i<info_ptr->num_trans; i++)
-               info_ptr->trans[i] = 255 - info_ptr->trans[i];
+            int j;
+            for (j=0; j<(int)info_ptr->num_trans; j++)
+               info_ptr->trans[j] = 255 - info_ptr->trans[j];
          }
 #endif
       png_write_tRNS(png_ptr, info_ptr->trans, &(info_ptr->trans_values),
@@ -225,7 +230,8 @@ png_convert_to_rfc1123(png_structp png_ptr, png_timep ptime)
 
    if (png_ptr->time_buffer == NULL)
    {
-      png_ptr->time_buffer = (png_charp)png_malloc(png_ptr, 29*sizeof(char));
+      png_ptr->time_buffer = (png_charp)png_malloc(png_ptr, (png_uint_32)(29*
+         sizeof(char)));
    }
 
 #ifdef USE_FAR_KEYWORD
@@ -244,7 +250,7 @@ png_convert_to_rfc1123(png_structp png_ptr, png_timep ptime)
                ptime->year, ptime->hour % 24, ptime->minute % 60,
                ptime->second % 61);
 #endif
-   return png_ptr->time_buffer;
+   return ((png_charp)png_ptr->time_buffer);
 }
 #endif /* PNG_TIME_RFC1123_SUPPORTED */
 
@@ -284,7 +290,7 @@ png_create_write_struct(png_const_charp user_png_ver, voidp error_ptr,
    png_debug(1, "in png_create_write_struct\n");
    if ((png_ptr = (png_structp)png_create_struct(PNG_STRUCT_PNG)) == NULL)
    {
-      return (png_structp)NULL;
+      return ((png_structp)NULL);
    }
 #ifdef USE_FAR_KEYWORD
    if (setjmp(jmpbuf))
@@ -294,7 +300,7 @@ png_create_write_struct(png_const_charp user_png_ver, voidp error_ptr,
    {
       png_free(png_ptr, png_ptr->zbuf);
       png_destroy_struct(png_ptr);
-      return (png_structp)NULL;
+      return ((png_structp)NULL);
    }
 #ifdef USE_FAR_KEYWORD
    png_memcpy(png_ptr->jmpbuf,jmpbuf,sizeof(jmp_buf));
@@ -315,7 +321,8 @@ png_create_write_struct(png_const_charp user_png_ver, voidp error_ptr,
 
    /* initialize zbuf - compression buffer */
    png_ptr->zbuf_size = PNG_ZBUF_SIZE;
-   png_ptr->zbuf = png_malloc(png_ptr, png_ptr->zbuf_size);
+   png_ptr->zbuf = (png_bytep)png_malloc(png_ptr,
+      (png_uint_32)png_ptr->zbuf_size);
 
    png_set_write_fn(png_ptr, NULL, NULL, NULL);
 
@@ -324,7 +331,7 @@ png_create_write_struct(png_const_charp user_png_ver, voidp error_ptr,
       1, NULL, NULL);
 #endif
 
-   return (png_ptr);
+   return ((png_structp)png_ptr);
 }
 
 
@@ -346,7 +353,8 @@ png_write_init(png_structp png_ptr)
 
    /* initialize zbuf - compression buffer */
    png_ptr->zbuf_size = PNG_ZBUF_SIZE;
-   png_ptr->zbuf = png_malloc(png_ptr, png_ptr->zbuf_size);
+   png_ptr->zbuf = (png_bytep)png_malloc(png_ptr,
+      (png_uint_32)png_ptr->zbuf_size);
    png_set_write_fn(png_ptr, NULL, NULL, NULL);
 
 #if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
@@ -386,9 +394,13 @@ png_write_image(png_structp png_ptr, png_bytepp image)
    png_bytepp rp; /* points to current row */
 
    png_debug(1, "in png_write_image\n");
+#if defined(PNG_WRITE_INTERLACING_SUPPORTED)
    /* intialize interlace handling.  If image is not interlaced,
       this will set pass to 1 */
    num_pass = png_set_interlace_handling(png_ptr);
+#else
+   num_pass = 1;
+#endif
    /* loop through passes */
    for (pass = 0; pass < num_pass; pass++)
    {
@@ -478,6 +490,7 @@ png_write_row(png_structp png_ptr, png_bytep row)
    png_ptr->row_info.bit_depth = png_ptr->usr_bit_depth;
    png_ptr->row_info.pixel_depth = (png_byte)(png_ptr->row_info.bit_depth *
       png_ptr->row_info.channels);
+
    png_ptr->row_info.rowbytes = ((png_ptr->row_info.width *
       (png_uint_32)png_ptr->row_info.pixel_depth + 7) >> 3);
 
@@ -489,7 +502,8 @@ png_write_row(png_structp png_ptr, png_bytep row)
    png_debug1(3, "row_info->rowbytes = %d\n", png_ptr->row_info.rowbytes);
 
    /* Copy user's row into buffer, leaving room for filter byte. */
-   png_memcpy(png_ptr->row_buf + 1, row, png_ptr->row_info.rowbytes);
+   png_memcpy_check(png_ptr, png_ptr->row_buf + 1, row,
+      png_ptr->row_info.rowbytes);
 
 #if defined(PNG_WRITE_INTERLACING_SUPPORTED)
    /* handle interlacing */
@@ -602,7 +616,7 @@ png_destroy_write_struct(png_structpp png_ptr_ptr, png_infopp info_ptr_ptr)
       if (info_ptr->pcal_params != NULL)
       {
          int i;
-         for (i = 0; i < info_ptr->pcal_nparams; i++)
+         for (i = 0; i < (int)info_ptr->pcal_nparams; i++)
          {
             png_free(png_ptr, info_ptr->pcal_params[i]);
          }
@@ -705,7 +719,7 @@ png_set_filter(png_structp png_ptr, int method, int filters)
          if (png_ptr->do_filter & PNG_FILTER_SUB && png_ptr->sub_row == NULL)
          {
             png_ptr->sub_row = (png_bytep)png_malloc(png_ptr,
-               png_ptr->rowbytes + 1);
+              (png_ptr->rowbytes + 1));
             png_ptr->sub_row[0] = PNG_FILTER_VALUE_SUB;
          }
 
@@ -719,7 +733,7 @@ png_set_filter(png_structp png_ptr, int method, int filters)
             else
             {
                png_ptr->up_row = (png_bytep)png_malloc(png_ptr,
-                  png_ptr->rowbytes + 1);
+                  (png_ptr->rowbytes + 1));
                png_ptr->up_row[0] = PNG_FILTER_VALUE_UP;
             }
          }
@@ -734,7 +748,7 @@ png_set_filter(png_structp png_ptr, int method, int filters)
             else
             {
                png_ptr->avg_row = (png_bytep)png_malloc(png_ptr,
-                  png_ptr->rowbytes + 1);
+                  (png_ptr->rowbytes + 1));
                png_ptr->avg_row[0] = PNG_FILTER_VALUE_AVG;
             }
          }
@@ -749,8 +763,8 @@ png_set_filter(png_structp png_ptr, int method, int filters)
             }
             else
             {
-               png_ptr->paeth_row = (png_bytep )png_malloc(png_ptr,
-                  png_ptr->rowbytes + 1);
+               png_ptr->paeth_row = (png_bytep)png_malloc(png_ptr,
+                  (png_ptr->rowbytes + 1));
                png_ptr->paeth_row[0] = PNG_FILTER_VALUE_PAETH;
             }
          }
@@ -806,7 +820,7 @@ png_set_filter_heuristics(png_structp png_ptr, int heuristic_method,
       if (png_ptr->prev_filters == NULL)
       {
          png_ptr->prev_filters = (png_bytep)png_malloc(png_ptr,
-            sizeof(png_byte) * num_weights);
+            (png_uint_32)(sizeof(png_byte) * num_weights));
 
          /* To make sure that the weighting starts out fairly */
          for (i = 0; i < num_weights; i++)
@@ -817,11 +831,11 @@ png_set_filter_heuristics(png_structp png_ptr, int heuristic_method,
 
       if (png_ptr->filter_weights == NULL)
       {
-         png_ptr->filter_weights = (png_uint_16p)png_malloc(png_ptr,
-            sizeof(png_uint_16) * num_weights);
+         png_ptr->filter_weights = png_malloc(png_ptr,
+            (png_uint_32)(sizeof(png_uint_16) * num_weights));
 
-         png_ptr->inv_filter_weights = (png_uint_16p)png_malloc(png_ptr,
-            sizeof(png_uint_16) * num_weights);
+         png_ptr->inv_filter_weights = png_malloc(png_ptr,
+            (png_uint_32)(sizeof(png_uint_16) * num_weights));
 
          for (i = 0; i < num_weights; i++)
          {
@@ -852,11 +866,11 @@ png_set_filter_heuristics(png_structp png_ptr, int heuristic_method,
     */
    if (png_ptr->filter_costs == NULL)
    {
-      png_ptr->filter_costs = (png_uint_16p)png_malloc(png_ptr,
-         sizeof(png_uint_16) * PNG_FILTER_VALUE_LAST);
+      png_ptr->filter_costs = png_malloc(png_ptr,
+         (png_uint_32)(sizeof(png_uint_16) * PNG_FILTER_VALUE_LAST));
 
       png_ptr->inv_filter_costs = (png_uint_16p)png_malloc(png_ptr,
-         sizeof(png_uint_16) * PNG_FILTER_VALUE_LAST);
+         (png_uint_32)(sizeof(png_uint_16) * PNG_FILTER_VALUE_LAST));
 
       for (i = 0; i < PNG_FILTER_VALUE_LAST; i++)
       {

pngwtran.c

@@ -1,12 +1,12 @@
 
 /* pngwtran.c - transforms the data in a row for PNG writers
  *
- * libpng 0.98
+ * libpng 0.99e
  * For conditions of distribution and use, see copyright notice in png.h
  * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
  * Copyright (c) 1996, 1997 Andreas Dilger
  * Copyright (c) 1998, Glenn Randers-Pehrson
- * January 16, 1998
+ * February 28, 1998
  */
 
 #define PNG_INTERNAL
@@ -24,6 +24,10 @@ png_do_write_transformations(png_structp png_ptr)
       png_do_strip_filler(&(png_ptr->row_info), png_ptr->row_buf + 1,
          png_ptr->flags);
 #endif
+#if defined(PNG_WRITE_PACKSWAP_SUPPORTED)
+   if (png_ptr->transformations & PNG_PACKSWAP)
+      png_do_packswap(&(png_ptr->row_info), png_ptr->row_buf + 1);
+#endif
 #if defined(PNG_WRITE_PACK_SUPPORTED)
    if (png_ptr->transformations & PNG_PACK)
       png_do_pack(&(png_ptr->row_info), png_ptr->row_buf + 1,
@@ -38,14 +42,14 @@ png_do_write_transformations(png_structp png_ptr)
    if (png_ptr->transformations & PNG_SWAP_BYTES)
       png_do_swap(&(png_ptr->row_info), png_ptr->row_buf + 1);
 #endif
-#if defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
-   if (png_ptr->transformations & PNG_SWAP_ALPHA)
-      png_do_write_swap_alpha(&(png_ptr->row_info), png_ptr->row_buf + 1);
-#endif
 #if defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
    if (png_ptr->transformations & PNG_INVERT_ALPHA)
       png_do_write_invert_alpha(&(png_ptr->row_info), png_ptr->row_buf + 1);
 #endif
+#if defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
+   if (png_ptr->transformations & PNG_SWAP_ALPHA)
+      png_do_write_swap_alpha(&(png_ptr->row_info), png_ptr->row_buf + 1);
+#endif
 #if defined(PNG_WRITE_BGR_SUPPORTED)
    if (png_ptr->transformations & PNG_BGR)
       png_do_bgr(&(png_ptr->row_info), png_ptr->row_buf + 1);
@@ -223,7 +227,7 @@ png_do_shift(png_row_infop row_info, png_bytep row, png_color_8p bit_depth)
          channels++;
       }
 
-      /* with low row dephts, could only be grayscale, so one channel */
+      /* with low row depths, could only be grayscale, so one channel */
       if (row_info->bit_depth < 8)
       {
          png_bytep bp;

pngwutil.c

@@ -1,12 +1,12 @@
 
 /* pngwutil.c - utilities to write a PNG file
  *
- * libpng 0.98
+ * libpng 0.99e
  * For conditions of distribution and use, see copyright notice in png.h
  * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
  * Copyright (c) 1996, 1997 Andreas Dilger
  * Copyright (c) 1998, Glenn Randers-Pehrson
- * January 16, 1998
+ * February 28, 1998
  */
 
 #define PNG_INTERNAL
@@ -200,12 +200,16 @@ png_write_IHDR(png_structp png_ptr, png_uint_32 width, png_uint_32 height,
       filter_type = PNG_FILTER_TYPE_BASE;
    }
 
+#ifdef PNG_WRITE_INTERLACING_SUPPORTED
    if (interlace_type != PNG_INTERLACE_NONE &&
       interlace_type != PNG_INTERLACE_ADAM7)
    {
       png_warning(png_ptr, "Invalid interlace type specified");
       interlace_type = PNG_INTERLACE_ADAM7;
    }
+#else
+   interlace_type=PNG_INTERLACE_NONE;
+#endif
 
    /* save off the relevent information */
    png_ptr->bit_depth = (png_byte)bit_depth;
@@ -351,7 +355,7 @@ png_write_sRGB(png_structp png_ptr, int srgb_intent)
    png_byte buf[1];
 
    png_debug(1, "in png_write_sRGB\n");
-   if(srgb_intent > 3)
+   if(srgb_intent >= PNG_sRGB_INTENT_LAST)
          png_warning(png_ptr,
             "Invalid sRGB rendering intent specified");
    buf[0]=(png_byte)srgb_intent;
@@ -371,7 +375,7 @@ png_write_sBIT(png_structp png_ptr, png_color_8p sbit, int color_type)
    /* make sure we don't depend upon the order of PNG_COLOR_8 */
    if (color_type & PNG_COLOR_MASK_COLOR)
    {
-      int maxbits;
+      png_byte maxbits;
 
       maxbits = color_type==PNG_COLOR_TYPE_PALETTE ? 8:png_ptr->usr_bit_depth;
       if (sbit->red == 0 || sbit->red > maxbits || 
@@ -482,7 +486,7 @@ png_write_tRNS(png_structp png_ptr, png_bytep trans, png_color_16p tran,
    png_debug(1, "in png_write_tRNS\n");
    if (color_type == PNG_COLOR_TYPE_PALETTE)
    {
-      if (num_trans <= 0 || num_trans > png_ptr->num_palette)
+      if (num_trans <= 0 || num_trans > (int)png_ptr->num_palette)
       {
          png_warning(png_ptr,"Invalid number of transparent colors specified");
          return;
@@ -547,13 +551,13 @@ png_write_bKGD(png_structp png_ptr, png_color_16p back, int color_type)
 #if defined(PNG_WRITE_hIST_SUPPORTED)
 /* write the histogram */
 void
-png_write_hIST(png_structp png_ptr, png_uint_16p hist, png_uint_32 num_hist)
+png_write_hIST(png_structp png_ptr, png_uint_16p hist, int num_hist)
 {
-   png_uint_32 i;
+   int i;
    png_byte buf[3];
 
    png_debug(1, "in png_write_hIST\n");
-   if (num_hist > png_ptr->num_palette)
+   if (num_hist > (int)png_ptr->num_palette)
    {
       png_debug2(3, "num_hist = %d, num_palette = %d\n", num_hist,
          png_ptr->num_palette);
@@ -561,7 +565,7 @@ png_write_hIST(png_structp png_ptr, png_uint_16p hist, png_uint_32 num_hist)
       return;
    }
 
-   png_write_chunk_start(png_ptr, png_hIST, num_hist * 2);
+   png_write_chunk_start(png_ptr, png_hIST, (png_uint_32)(num_hist * 2));
    for (i = 0; i < num_hist; i++)
    {
       png_save_uint_16(buf, hist[i]);
@@ -595,12 +599,12 @@ png_check_keyword(png_structp png_ptr, png_charp key, png_charpp new_key)
    if (key == NULL || (key_len = png_strlen(key)) == 0)
    {
       png_chunk_warning(png_ptr, "zero length keyword");
-      return 0;
+      return ((png_size_t)0);
    }
 
    png_debug1(2, "Keyword to be checked is '%s'\n", key);
 
-   *new_key = (png_charp)png_malloc(png_ptr, key_len + 1);
+   *new_key = (png_charp)png_malloc(png_ptr, (png_uint_32)(key_len + 1));
 
    /* Replace non-printing characters with a blank and print a warning */
    for (kp = key, dp = *new_key; *kp != '\0'; kp++, dp++)
@@ -684,7 +688,7 @@ png_check_keyword(png_structp png_ptr, png_charp key, png_charpp new_key)
       key_len = 79;
    }
 
-   return key_len;
+   return (key_len);
 }
 #endif
 
@@ -811,17 +815,18 @@ png_write_zTXt(png_structp png_ptr, png_charp key, png_charp text,
 
                old_ptr = output_ptr;
                output_ptr = (png_charpp)png_malloc(png_ptr,
-                  max_output_ptr * sizeof (png_charpp));
+                  (png_uint_32)(max_output_ptr * sizeof (png_charpp)));
                png_memcpy(output_ptr, old_ptr, old_max * sizeof (png_charp));
                png_free(png_ptr, old_ptr);
             }
             else
                output_ptr = (png_charpp)png_malloc(png_ptr,
-                  max_output_ptr * sizeof (png_charp));
+                  (png_uint_32)(max_output_ptr * sizeof (png_charp)));
          }
 
          /* save the data */
-         output_ptr[num_output_ptr] = png_malloc(png_ptr, png_ptr->zbuf_size);
+         output_ptr[num_output_ptr] = (png_charp)png_malloc(png_ptr,
+            (png_uint_32)png_ptr->zbuf_size);
          png_memcpy(output_ptr[num_output_ptr], png_ptr->zbuf,
             png_ptr->zbuf_size);
          num_output_ptr++;
@@ -864,18 +869,18 @@ png_write_zTXt(png_structp png_ptr, png_charp key, png_charp text,
                old_ptr = output_ptr;
                /* This could be optimized to realloc() */
                output_ptr = (png_charpp)png_malloc(png_ptr,
-                  max_output_ptr * sizeof (png_charpp));
+                  (png_uint_32)(max_output_ptr * sizeof (png_charpp)));
                png_memcpy(output_ptr, old_ptr, old_max * sizeof (png_charp));
                png_free(png_ptr, old_ptr);
             }
             else
                output_ptr = (png_charpp)png_malloc(png_ptr,
-                  max_output_ptr * sizeof (png_charp));
+                  (png_uint_32)(max_output_ptr * sizeof (png_charp)));
          }
 
          /* save off the data */
-         output_ptr[num_output_ptr] = png_malloc(png_ptr,
-            png_ptr->zbuf_size);
+         output_ptr[num_output_ptr] = (png_charp)png_malloc(png_ptr,
+            (png_uint_32)png_ptr->zbuf_size);
          png_memcpy(output_ptr[num_output_ptr], png_ptr->zbuf,
             png_ptr->zbuf_size);
          num_output_ptr++;
@@ -963,7 +968,8 @@ png_write_pCAL(png_structp png_ptr, png_charp purpose, png_int_32 X0,
    png_debug1(3, "pCAL units length = %d\n", units_len);
    total_len = purpose_len + units_len + 10;
 
-   params_len = (png_uint_32p)png_malloc(png_ptr, nparams*sizeof(png_uint_32));
+   params_len = (png_uint_32p)png_malloc(png_ptr, (png_uint_32)(nparams
+      *sizeof(png_uint_32)));
 
    /* Find the length of each parameter, making sure we don't count the
       null terminator for the last parameter. */
@@ -975,7 +981,7 @@ png_write_pCAL(png_structp png_ptr, png_charp purpose, png_int_32 X0,
    }
 
    png_debug1(3, "pCAL total length = %d\n", total_len);
-   png_write_chunk_start(png_ptr, png_pCAL, total_len);
+   png_write_chunk_start(png_ptr, png_pCAL, (png_uint_32)total_len);
    png_write_chunk_data(png_ptr, (png_bytep)new_purpose, purpose_len);
    png_save_int_32(buf, X0);
    png_save_int_32(buf + 4, X1);
@@ -1058,14 +1064,14 @@ png_write_start_row(png_structp png_ptr)
                             png_ptr->usr_bit_depth + 7) >> 3) + 1);
 
    /* set up row buffer */
-   png_ptr->row_buf = (png_bytep)png_malloc(png_ptr, buf_size);
+   png_ptr->row_buf = (png_bytep)png_malloc(png_ptr, (png_uint_32)buf_size);
    png_ptr->row_buf[0] = PNG_FILTER_VALUE_NONE;
 
    /* set up filtering buffer, if using this filter */
    if (png_ptr->do_filter & PNG_FILTER_SUB)
    {
       png_ptr->sub_row = (png_bytep)png_malloc(png_ptr,
-         png_ptr->rowbytes + 1);
+         (png_ptr->rowbytes + 1));
       png_ptr->sub_row[0] = PNG_FILTER_VALUE_SUB;
    }
 
@@ -1073,31 +1079,32 @@ png_write_start_row(png_structp png_ptr)
    if (png_ptr->do_filter & (PNG_FILTER_AVG | PNG_FILTER_UP | PNG_FILTER_PAETH))
    {
      /* set up previous row buffer */
-      png_ptr->prev_row = (png_bytep)png_malloc(png_ptr, buf_size);
+      png_ptr->prev_row = (png_bytep)png_malloc(png_ptr, (png_uint_32)buf_size);
       png_memset(png_ptr->prev_row, 0, buf_size);
 
       if (png_ptr->do_filter & PNG_FILTER_UP)
       {
          png_ptr->up_row = (png_bytep )png_malloc(png_ptr,
-            png_ptr->rowbytes + 1);
+            (png_ptr->rowbytes + 1));
          png_ptr->up_row[0] = PNG_FILTER_VALUE_UP;
       }
 
       if (png_ptr->do_filter & PNG_FILTER_AVG)
       {
-         png_ptr->avg_row = (png_bytep )png_malloc(png_ptr,
-            png_ptr->rowbytes + 1);
+         png_ptr->avg_row = (png_bytep)png_malloc(png_ptr,
+            (png_ptr->rowbytes + 1));
          png_ptr->avg_row[0] = PNG_FILTER_VALUE_AVG;
       }
 
       if (png_ptr->do_filter & PNG_FILTER_PAETH)
       {
          png_ptr->paeth_row = (png_bytep )png_malloc(png_ptr,
-            png_ptr->rowbytes + 1);
+            (png_ptr->rowbytes + 1));
          png_ptr->paeth_row[0] = PNG_FILTER_VALUE_PAETH;
       }
    }
 
+#ifdef PNG_WRITE_INTERLACING_SUPPORTED
    /* if interlaced, we need to set up width and height of pass */
    if (png_ptr->interlaced)
    {
@@ -1115,6 +1122,7 @@ png_write_start_row(png_structp png_ptr)
       }
    }
    else
+#endif
    {
       png_ptr->num_rows = png_ptr->height;
       png_ptr->usr_width = png_ptr->width;
@@ -1137,6 +1145,7 @@ png_write_finish_row(png_structp png_ptr)
    if (png_ptr->row_number < png_ptr->num_rows)
       return;
 
+#ifdef PNG_WRITE_INTERLACING_SUPPORTED
    /* if interlaced, go to next pass */
    if (png_ptr->interlaced)
    {
@@ -1178,6 +1187,7 @@ png_write_finish_row(png_structp png_ptr)
          return;
       }
    }
+#endif
 
    /* if we get here, we've just written the last row, so we need
       to flush the compressor */
@@ -1348,7 +1358,7 @@ png_do_write_interlace(png_row_infop row_info, png_bytep row, int pass)
                i += png_pass_inc[pass])
             {
                /* find out where the original pixel is */
-               sp = row + i * pixel_bytes;
+               sp = row + (png_size_t)i * pixel_bytes;
                /* move the pixel */
                if (dp != sp)
                   png_memcpy(dp, sp, pixel_bytes);
@@ -1363,9 +1373,8 @@ png_do_write_interlace(png_row_infop row_info, png_bytep row, int pass)
          png_pass_inc[pass] - 1 -
          png_pass_start[pass]) /
          png_pass_inc[pass];
-      row_info->rowbytes = ((row_info->width *
-         row_info->pixel_depth + 7) >> 3);
-
+         row_info->rowbytes = ((row_info->width *
+            row_info->pixel_depth + 7) >> 3);
    }
 }
 #endif
@@ -1412,7 +1421,7 @@ png_write_find_filter(png_structp png_ptr, png_row_infop row_info)
    {
       png_bytep rp;
       png_uint_32 sum = 0;
-      png_size_t i;
+      png_uint_32 i;
       int v;
 
       for (i = 0, rp = row_buf + 1; i < row_info->rowbytes; i++, rp++)
@@ -1429,7 +1438,7 @@ png_write_find_filter(png_structp png_ptr, png_row_infop row_info)
          sumhi = (sum >> PNG_HISHIFT) & PNG_HIMASK; /* Gives us some footroom */
 
          /* Reduce the sum if we match any of the previous rows */
-         for (i = 0; i < png_ptr->num_prev_filters; i++)
+         for (i = 0; i < (png_uint_32)png_ptr->num_prev_filters; i++)
          {
             if (png_ptr->prev_filters[i] == PNG_FILTER_NONE)
             {
@@ -1463,7 +1472,7 @@ png_write_find_filter(png_structp png_ptr, png_row_infop row_info)
    {
       png_bytep rp, dp, lp;
       png_uint_32 sum = 0, lmins = mins;
-      png_size_t i;
+      png_uint_32 i;
       int v;
 
 #if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
@@ -1477,7 +1486,7 @@ png_write_find_filter(png_structp png_ptr, png_row_infop row_info)
          lmlo = lmins & PNG_LOMASK;
          lmhi = (lmins >> PNG_HISHIFT) & PNG_HIMASK;
 
-         for (i = 0; i < png_ptr->num_prev_filters; i++)
+         for (i = 0; i < (png_uint_32)png_ptr->num_prev_filters; i++)
          {
             if (png_ptr->prev_filters[i] == PNG_FILTER_VALUE_SUB)
             {
@@ -1507,7 +1516,8 @@ png_write_find_filter(png_structp png_ptr, png_row_infop row_info)
 
          sum += (v < 128) ? v : 256 - v;
       }
-      for (lp = row_buf + 1; i < row_info->rowbytes; i++, rp++, lp++, dp++)
+      for (lp = row_buf + 1; i < row_info->rowbytes;
+         i++, rp++, lp++, dp++)
       {
          v = *dp = (png_byte)(((int)*rp - (int)*lp) & 0xff);
 
@@ -1524,7 +1534,7 @@ png_write_find_filter(png_structp png_ptr, png_row_infop row_info)
          sumlo = sum & PNG_LOMASK;
          sumhi = (sum >> PNG_HISHIFT) & PNG_HIMASK;
 
-         for (i = 0; i < png_ptr->num_prev_filters; i++)
+         for (i = 0; i < (png_uint_32)png_ptr->num_prev_filters; i++)
          {
             if (png_ptr->prev_filters[i] == PNG_FILTER_VALUE_SUB)
             {
@@ -1559,7 +1569,7 @@ png_write_find_filter(png_structp png_ptr, png_row_infop row_info)
    {
       png_bytep rp, dp, pp;
       png_uint_32 sum = 0, lmins = mins;
-      png_size_t i;
+      png_uint_32 i;
       int v;
 
 #if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
@@ -1569,7 +1579,7 @@ png_write_find_filter(png_structp png_ptr, png_row_infop row_info)
          lmlo = lmins & PNG_LOMASK;
          lmhi = (lmins >> PNG_HISHIFT) & PNG_HIMASK;
 
-         for (i = 0; i < png_ptr->num_prev_filters; i++)
+         for (i = 0; i < (png_uint_32)png_ptr->num_prev_filters; i++)
          {
             if (png_ptr->prev_filters[i] == PNG_FILTER_VALUE_UP)
             {
@@ -1593,7 +1603,8 @@ png_write_find_filter(png_structp png_ptr, png_row_infop row_info)
 #endif
 
       for (i = 0, rp = row_buf + 1, dp = png_ptr->up_row + 1,
-           pp = prev_row + 1; i < row_info->rowbytes; i++, rp++, pp++, dp++)
+           pp = prev_row + 1; i < row_info->rowbytes;
+           i++, rp++, pp++, dp++)
       {
          v = *dp = (png_byte)(((int)*rp - (int)*pp) & 0xff);
 
@@ -1610,7 +1621,7 @@ png_write_find_filter(png_structp png_ptr, png_row_infop row_info)
          sumlo = sum & PNG_LOMASK;
          sumhi = (sum >> PNG_HISHIFT) & PNG_HIMASK;
 
-         for (i = 0; i < png_ptr->num_prev_filters; i++)
+         for (i = 0; i < (png_uint_32)png_ptr->num_prev_filters; i++)
          {
             if (png_ptr->prev_filters[i] == PNG_FILTER_UP)
             {
@@ -1645,7 +1656,7 @@ png_write_find_filter(png_structp png_ptr, png_row_infop row_info)
    {
       png_bytep rp, dp, pp, lp;
       png_uint_32 sum = 0, lmins = mins;
-      png_size_t i;
+      png_uint_32 i;
       int v;
 
 #if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
@@ -1655,7 +1666,7 @@ png_write_find_filter(png_structp png_ptr, png_row_infop row_info)
          lmlo = lmins & PNG_LOMASK;
          lmhi = (lmins >> PNG_HISHIFT) & PNG_HIMASK;
 
-         for (i = 0; i < png_ptr->num_prev_filters; i++)
+         for (i = 0; i < (png_uint_32)png_ptr->num_prev_filters; i++)
          {
             if (png_ptr->prev_filters[i] == PNG_FILTER_VALUE_AVG)
             {
@@ -1738,7 +1749,7 @@ png_write_find_filter(png_structp png_ptr, png_row_infop row_info)
    {
       png_bytep rp, dp, pp, cp, lp;
       png_uint_32 sum = 0, lmins = mins;
-      png_size_t i;
+      png_uint_32 i;
       int v;
 
 #if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
@@ -1772,7 +1783,7 @@ png_write_find_filter(png_structp png_ptr, png_row_infop row_info)
 #endif
 
       for (i = 0, rp = row_buf + 1, dp = png_ptr->paeth_row + 1,
-           pp = prev_row + 1; i < bpp; i++, rp++, pp++, dp++)
+           pp = prev_row + 1; (unsigned)i < bpp; i++, rp++, pp++, dp++)
       {
          v = *dp = (png_byte)(((int)*rp - (int)*pp) & 0xff);
 
@@ -1850,9 +1861,9 @@ png_write_find_filter(png_structp png_ptr, png_row_infop row_info)
    /* Save the type of filter we picked this time for future calculations */
    if (png_ptr->num_prev_filters > 0)
    {
-      png_byte i;
+      int i;
 
-      for (i = 1; i < png_ptr->num_prev_filters; i++)
+      for (i = 1; i < (int)png_ptr->num_prev_filters; i++)
       {
          png_ptr->prev_filters[i] = png_ptr->prev_filters[i - 1];
       }
@@ -1921,4 +1932,3 @@ png_write_filtered_row(png_structp png_ptr, png_bytep filtered_row)
    }
 #endif /* PNG_WRITE_FLUSH_SUPPORTED */
 }
-