[libpng16] tests backported from libpng 1.7

This updates libpng16 with all the test changes from libpng17,
including changes to pngvalid.c to ensure that the original,
distributed, version of contrib/visupng/cexcept.h can be used.

pngvalid contains the correction to the use of SAVE/STORE_
UNKNOWN_CHUNKS; a bug revealed by changes in libpng 1.7.  More
tests contain the --strict option to detect warnings and the
pngvalid-standard test has been corrected so that it does not
turn on progresive-read (there is a separate test which does
that.)

Some signed/unsigned fixes have been made.

Signed-off-by: John Bowler <jbowler@acm.org>

contrib/examples/pngpixel.c

@@ -87,7 +87,7 @@ print_pixel(png_structp png_ptr, png_infop info_ptr, png_const_bytep row,
        */
       case PNG_COLOR_TYPE_PALETTE:
          {
-            PNG_CONST unsigned int index = component(row, x, 0, bit_depth, 1);
+            PNG_CONST int index = component(row, x, 0, bit_depth, 1);
             png_colorp palette = NULL;
             int num_palette = 0;
 

contrib/libtests/makepng.c

@@ -107,7 +107,7 @@ typedef struct chunk_insert
    png_charp            parameters[1];
 } chunk_insert;
 
-static int
+static unsigned int
 channels_of_type(int color_type)
 {
    if (color_type & PNG_COLOR_MASK_PALETTE)
@@ -128,7 +128,7 @@ channels_of_type(int color_type)
    }
 }
 
-static int
+static unsigned int
 pixel_depth_of_type(int color_type, int bit_depth)
 {
    return channels_of_type(color_type) * bit_depth;
@@ -682,7 +682,11 @@ write_png(const char **name, FILE *fp, int color_type, int bit_depth,
       png_set_filter(png_ptr, PNG_FILTER_TYPE_BASE, filters);
 
       {
+#        ifdef PNG_WRITE_INTERLACING_SUPPORTED
             int passes = png_set_interlace_handling(png_ptr);
+#        else /* !WRITE_INTERLACING */
+            int passes = 1;
+#        endif /* !WRITE_INTERLACING */
          int pass;
          png_size_t rowbytes = png_get_rowbytes(png_ptr, info_ptr);
 

contrib/libtests/pngimage.c

@@ -2,7 +2,7 @@
  *
  * Copyright (c) 2015 John Cunningham Bowler
  *
- * Last changed in libpng 1.6.18 [July 23, 2015]
+ * Last changed in libpng 1.6.18 [(PENDING RELEASE)]
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
@@ -236,10 +236,12 @@ static struct transform_info
        */
 #endif
 #ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED
-   T(SCALE_16,            NONE, X,   X,   16,  R)
+   T(SCALE_16,            NONE, X,   X,   16,  R),
       /* scales 16-bit components to 8-bits. */
 #endif
 
+   { NULL /*name*/, 0, 0, 0, 0, 0, 0, 0/*!tested*/ }
+
 #undef T
 };
 
@@ -294,7 +296,7 @@ transform_name(int t)
 
    t &= -t; /* first set bit */
 
-   for (i=0; i<TTABLE_SIZE; ++i)
+   for (i=0; i<TTABLE_SIZE; ++i) if (transform_info[i].name != NULL)
    {
       if ((transform_info[i].transform & t) != 0)
          return transform_info[i].name;
@@ -315,7 +317,7 @@ validate_T(void)
 {
    unsigned int i;
 
-   for (i=0; i<TTABLE_SIZE; ++i)
+   for (i=0; i<TTABLE_SIZE; ++i) if (transform_info[i].name != NULL)
    {
       if (transform_info[i].when & TRANSFORM_R)
          read_transforms |= transform_info[i].transform;
@@ -505,6 +507,7 @@ typedef enum
 #define SKIP_BUGS       0x100 /* Skip over known bugs */
 #define LOG_SKIPPED     0x200 /* Log skipped bugs */
 #define FIND_BAD_COMBOS 0x400 /* Attempt to deduce bad combos */
+#define LIST_COMBOS     0x800 /* List combos by name */
 
 /* Result masks apply to the result bits in the 'results' field below; these
  * bits are simple 1U<<error_level.  A pass requires either nothing worse than
@@ -690,7 +693,35 @@ display_log(struct display *dp, error_level level, const char *fmt, ...)
          int tr = dp->transforms;
 
          if (is_combo(tr))
+         {
+            if (dp->options & LIST_COMBOS)
+            {
+               int trx = tr;
+
+               fprintf(stderr, "(");
+               if (trx)
+               {
+                  int start = 0;
+
+                  while (trx)
+                  {
+                     int trz = trx & -trx;
+
+                     if (start) fprintf(stderr, "+");
+                     fprintf(stderr, "%s", transform_name(trz));
+                     start = 1;
+                     trx &= ~trz;
+                  }
+               }
+
+               else
+                  fprintf(stderr, "-");
+               fprintf(stderr, ")");
+            }
+
+            else
                fprintf(stderr, "(0x%x)", tr);
+         }
 
          else
             fprintf(stderr, "(%s)", transform_name(tr));
@@ -910,7 +941,7 @@ update_display(struct display *dp)
       int bd = dp->bit_depth;
       unsigned int i;
 
-      for (i=0; i<TTABLE_SIZE; ++i)
+      for (i=0; i<TTABLE_SIZE; ++i) if (transform_info[i].name != NULL)
       {
          int transform = transform_info[i].transform;
 
@@ -935,9 +966,6 @@ update_display(struct display *dp)
 
       dp->active_transforms = active;
       dp->ignored_transforms = inactive; /* excluding write-only transforms */
-
-      if (active == 0)
-         display_log(dp, INTERNAL_ERROR, "bad transform table");
    }
 }
 
@@ -1588,6 +1616,12 @@ main(const int argc, const char * const * const argv)
       else if (strcmp(name, "--nofind-bad-combos") == 0)
          d.options &= ~FIND_BAD_COMBOS;
 
+      else if (strcmp(name, "--list-combos") == 0)
+         d.options |= LIST_COMBOS;
+
+      else if (strcmp(name, "--nolist-combos") == 0)
+         d.options &= ~LIST_COMBOS;
+
       else if (name[0] == '-' && name[1] == '-')
       {
          fprintf(stderr, "pngimage: %s: unknown option\n", name);

contrib/libtests/pngunknown.c

@@ -363,7 +363,7 @@ ancillary(const char *name)
    return PNG_CHUNK_ANCILLARY(PNG_U32(name[0], name[1], name[2], name[3]));
 }
 
-#ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED
+#ifdef PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED
 static int
 ancillaryb(const png_byte *name)
 {
@@ -554,7 +554,7 @@ read_callback(png_structp pp, png_unknown_chunkp pc)
    /* However if there is no support to store unknown chunks don't ask libpng to
     * do it; there will be an png_error.
     */
-#  ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED
+#  ifdef PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED
       return discard;
 #  else
       return 1; /*handled; discard*/
@@ -562,7 +562,7 @@ read_callback(png_structp pp, png_unknown_chunkp pc)
 }
 #endif /* READ_USER_CHUNKS_SUPPORTED */
 
-#ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED
+#ifdef PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED
 static png_uint_32
 get_unknown(display *d, png_infop info_ptr, int after_IDAT)
 {
@@ -722,11 +722,17 @@ check(FILE *fp, int argc, const char **argv, png_uint_32p flags/*out*/,
                    * in this case, so we just check the arguments!  This could
                    * be improved in the future by using the read callback.
                    */
+#                 if PNG_LIBPNG_VER >= 10700 &&\
+                     !defined(PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED)
+                     if (option < PNG_HANDLE_CHUNK_IF_SAFE)
+#                 endif /* 1.7+ SAVE_UNKNOWN_CHUNKS */
+                  {
                      png_byte name[5];
 
                      memcpy(name, chunk_info[chunk].name, 5);
                      png_set_keep_unknown_chunks(d->png_ptr, option, name, 1);
                      chunk_info[chunk].keep = option;
+                  }
                   continue;
                }
 
@@ -735,7 +741,12 @@ check(FILE *fp, int argc, const char **argv, png_uint_32p flags/*out*/,
             case 7: /* default */
                if (memcmp(argv[i], "default", 7) == 0)
                {
+#                 if PNG_LIBPNG_VER >= 10700 &&\
+                     !defined(PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED)
+                     if (option < PNG_HANDLE_CHUNK_IF_SAFE)
+#                 endif /* 1.7+ SAVE_UNKNOWN_CHUNKS */
                      png_set_keep_unknown_chunks(d->png_ptr, option, NULL, 0);
+
                   d->keep = option;
                   continue;
                }
@@ -745,7 +756,12 @@ check(FILE *fp, int argc, const char **argv, png_uint_32p flags/*out*/,
             case 3: /* all */
                if (memcmp(argv[i], "all", 3) == 0)
                {
+#                 if PNG_LIBPNG_VER >= 10700 &&\
+                     !defined(PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED)
+                     if (option < PNG_HANDLE_CHUNK_IF_SAFE)
+#                 endif /* 1.7+ SAVE_UNKNOWN_CHUNKS */
                      png_set_keep_unknown_chunks(d->png_ptr, option, NULL, -1);
+
                   d->keep = option;
 
                   for (chunk = 0; chunk < NINFO; ++chunk)

contrib/libtests/readpng.c

@@ -31,6 +31,13 @@
 #  include "../../png.h"
 #endif
 
+#if PNG_LIBPNG_VER < 10700
+   /* READ_INTERLACING was used instead of READ_DEINTERLACE. */
+#  ifdef PNG_READ_INTERLACING_SUPPORTED
+#     define PNG_READ_DEINTERLACE_SUPPORTED
+#  endif
+#endif
+
 static int
 read_png(FILE *fp)
 {
@@ -70,7 +77,12 @@ read_png(FILE *fp)
 
       {
          png_uint_32 height = png_get_image_height(png_ptr, info_ptr);
+#        ifdef PNG_READ_DEINTERLACE_SUPPORTED
             int passes = png_set_interlace_handling(png_ptr);
+#        else
+            int passes = png_get_interlace_type(png_ptr, info_ptr) == 
+               PNG_INTERLACE_ADAM7 ? PNG_INTERLACE_ADAM7_PASSES : 1;
+#        endif
          int pass;
 
          png_start_read_image(png_ptr);
@@ -79,6 +91,11 @@ read_png(FILE *fp)
          {
             png_uint_32 y = height;
 
+#           ifndef PNG_READ_DEINTERLACE_SUPPORTED
+               if (passes == PNG_INTERLACE_ADAM7_PASSES)
+                  y = PNG_PASS_ROWS(y, pass);
+#           endif
+
             /* NOTE: this trashes the row each time; interlace handling won't
              * work, but this avoids memory thrashing for speed testing.
              */

contrib/tools/pngfix.c

@@ -52,7 +52,10 @@
 #ifdef PNG_SETJMP_SUPPORTED
 #include <setjmp.h>
 
-#if defined(PNG_READ_SUPPORTED) && defined(PNG_EASY_ACCESS_SUPPORTED)
+#if defined(PNG_READ_SUPPORTED) && defined(PNG_EASY_ACCESS_SUPPORTED) &&\
+   (defined(PNG_READ_DEINTERLACE_SUPPORTED) ||\
+    defined(PNG_READ_INTERLACING_SUPPORTED))
+
 /* zlib.h defines the structure z_stream, an instance of which is included
  * in this structure and is required for decompressing the LZ compressed
  * data in PNG files.
@@ -4030,7 +4033,7 @@ main(void)
 int
 main(void)
 {
-   fprintf(stderr, "pngfix does not work without read support\n");
+   fprintf(stderr, "pngfix does not work without read deinterlace support\n");
    return 77;
 }
 #endif /* PNG_READ_SUPPORTED && PNG_EASY_ACCESS_SUPPORTED */

contrib/visupng/PngFile.c

@@ -136,7 +136,7 @@ BOOL PngLoadImage (PTSTR pstrFileName, png_byte **ppbImageData,
 
     /* create the two png(-info) structures */
 
-    png_ptr = png_create_read_struct(png_get_libpng_ver(NULL), NULL,
+    png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL,
       (png_error_ptr)png_cexcept_error, (png_error_ptr)NULL);
     if (!png_ptr)
     {
@@ -313,7 +313,7 @@ BOOL PngSaveImage (PTSTR pstrFileName, png_byte *pDiData,
 
     /* prepare the standard PNG structures */
 
-    png_ptr = png_create_write_struct(png_get_libpng_ver(NULL), NULL,
+    png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL,
       (png_error_ptr)png_cexcept_error, (png_error_ptr)NULL);
     if (!png_ptr)
     {

contrib/visupng/cexcept.h

@@ -1,12 +1,11 @@
 /*===
-cexcept.h 2.0.1 (2008-Jul-19-Sat, modified 2015-Jun-03-Mon)
+cexcept.h 2.0.1 (2008-Jul-19-Sat)
 http://www.nicemice.net/cexcept/
 Adam M. Costello
 http://www.nicemice.net/amc/
 
 An interface for exception-handling in ANSI C (C89 and subsequent ISO
-standards), developed jointly with Cosmin Truta.  Revised by John Bowler,
+standards), developed jointly with Cosmin Truta.
-June 2015, to declare exception_env and exception_prev "volatile".
 
     Copyright (c) 2000-2008 Adam M. Costello and Cosmin Truta.
     This software may be modified only if its author and version
@@ -211,7 +210,7 @@ struct exception_context { \
 
 #define Try \
   { \
-    jmp_buf * volatile exception__prev, exception__env; \
+    jmp_buf *exception__prev, exception__env; \
     exception__prev = the_exception_context->penv; \
     the_exception_context->penv = &exception__env; \
     if (setjmp(exception__env) == 0) { \

tests/pngimage-full

@@ -1,2 +1,2 @@
 #!/bin/sh
-exec ./pngimage --exhaustive --log "${srcdir}/contrib/pngsuite/"*.png
+exec ./pngimage --exhaustive --list-combos --log "${srcdir}/contrib/pngsuite/"*.png

tests/pngimage-quick

@@ -1,2 +1,2 @@
 #!/bin/sh
-exec ./pngimage --log "${srcdir}/contrib/pngsuite/"*.png
+exec ./pngimage --list-combos --log "${srcdir}/contrib/pngsuite/"*.png

tests/pngunknown-IDAT

@@ -1,2 +1,2 @@
 #!/bin/sh
-exec ./pngunknown default=discard IDAT=save "${srcdir}/pngtest.png"
+exec ./pngunknown --strict default=discard IDAT=save "${srcdir}/pngtest.png"

tests/pngunknown-discard

@@ -1,2 +1,2 @@
 #!/bin/sh
-exec ./pngunknown default=discard "${srcdir}/pngtest.png"
+exec ./pngunknown --strict default=discard "${srcdir}/pngtest.png"

tests/pngunknown-if-safe

@@ -1,2 +1,2 @@
 #!/bin/sh
-exec ./pngunknown default=if-safe "${srcdir}/pngtest.png"
+exec ./pngunknown --strict default=if-safe "${srcdir}/pngtest.png"

tests/pngunknown-sAPI

@@ -1,2 +1,2 @@
 #!/bin/sh
-exec ./pngunknown bKGD=save cHRM=save gAMA=save all=discard iCCP=save sBIT=save sRGB=save "${srcdir}/pngtest.png"
+exec ./pngunknown --strict bKGD=save cHRM=save gAMA=save all=discard iCCP=save sBIT=save sRGB=save "${srcdir}/pngtest.png"

tests/pngunknown-sTER

@@ -1,2 +1,2 @@
 #!/bin/sh
-exec ./pngunknown sTER=if-safe "${srcdir}/pngtest.png"
+exec ./pngunknown --strict sTER=if-safe "${srcdir}/pngtest.png"

tests/pngunknown-save

@@ -1,2 +1,2 @@
 #!/bin/sh
-exec ./pngunknown default=save "${srcdir}/pngtest.png"
+exec ./pngunknown --strict default=save "${srcdir}/pngtest.png"

tests/pngunknown-vpAg

@@ -1,2 +1,2 @@
 #!/bin/sh
-exec ./pngunknown vpAg=if-safe "${srcdir}/pngtest.png"
+exec ./pngunknown --strict vpAg=if-safe "${srcdir}/pngtest.png"

tests/pngvalid-standard

@@ -1,2 +1,2 @@
 #!/bin/sh
-exec ./pngvalid --standard --progressive-read
+exec ./pngvalid --standard