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[libpng10] Imported from libpng-1.0.16.tar

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This commit is contained in:
Glenn Randers-Pehrson
2004-08-15 07:11:04 -05:00
parent 4fc3118b59
commit f47b4b1bf7
99 changed files with 3722 additions and 3976 deletions
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91
pngwutil.c
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@@ -1,9 +1,9 @@
/* pngwutil.c - utilities to write a PNG file
*
* libpng 1.0.15 - October 3, 2002
* libpng version 1.0.16 - August 15, 2004
* For conditions of distribution and use, see copyright notice in png.h
* Copyright (c) 1998-2002 Glenn Randers-Pehrson
* Copyright (c) 1998-2004 Glenn Randers-Pehrson
* (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
* (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
*/
@@ -234,14 +234,16 @@ png_text_compress(png_structp png_ptr,
old_ptr = comp->output_ptr;
comp->output_ptr = (png_charpp)png_malloc(png_ptr,
(png_uint_32)(comp->max_output_ptr * sizeof (png_charpp)));
(png_uint_32)(comp->max_output_ptr *
png_sizeof (png_charpp)));
png_memcpy(comp->output_ptr, old_ptr, old_max
* sizeof (png_charp));
* png_sizeof (png_charp));
png_free(png_ptr, old_ptr);
}
else
comp->output_ptr = (png_charpp)png_malloc(png_ptr,
(png_uint_32)(comp->max_output_ptr * sizeof (png_charp)));
(png_uint_32)(comp->max_output_ptr *
png_sizeof (png_charp)));
}
/* save the data */
@@ -283,14 +285,16 @@ png_text_compress(png_structp png_ptr,
old_ptr = comp->output_ptr;
/* This could be optimized to realloc() */
comp->output_ptr = (png_charpp)png_malloc(png_ptr,
(png_uint_32)(comp->max_output_ptr * sizeof (png_charpp)));
(png_uint_32)(comp->max_output_ptr *
png_sizeof (png_charpp)));
png_memcpy(comp->output_ptr, old_ptr,
old_max * sizeof (png_charp));
old_max * png_sizeof (png_charp));
png_free(png_ptr, old_ptr);
}
else
comp->output_ptr = (png_charpp)png_malloc(png_ptr,
(png_uint_32)(comp->max_output_ptr * sizeof (png_charp)));
(png_uint_32)(comp->max_output_ptr *
png_sizeof (png_charp)));
}
/* save off the data */
@@ -464,11 +468,12 @@ png_write_IHDR(png_structp png_ptr, png_uint_32 width, png_uint_32 height,
#if defined(PNG_MNG_FEATURES_SUPPORTED)
png_ptr->filter_type = (png_byte)filter_type;
#endif
png_ptr->compression_type = (png_byte)compression_type;
png_ptr->width = width;
png_ptr->height = height;
png_ptr->pixel_depth = (png_byte)(bit_depth * png_ptr->channels);
png_ptr->rowbytes = ((width * (png_size_t)png_ptr->pixel_depth + 7) >> 3);
png_ptr->rowbytes = PNG_ROWBYTES(png_ptr->pixel_depth, width);
/* set the usr info, so any transformations can modify it */
png_ptr->usr_width = png_ptr->width;
png_ptr->usr_bit_depth = png_ptr->bit_depth;
@@ -596,6 +601,46 @@ png_write_IDAT(png_structp png_ptr, png_bytep data, png_size_t length)
PNG_IDAT;
#endif
png_debug(1, "in png_write_IDAT\n");
/* Optimize the CMF field in the zlib stream. */
/* This hack of the zlib stream is compliant to the stream specification. */
if (!(png_ptr->mode & PNG_HAVE_IDAT) &&
png_ptr->compression_type == PNG_COMPRESSION_TYPE_BASE)
{
unsigned int z_cmf = data[0]; /* zlib compression method and flags */
if ((z_cmf & 0x0f) == 8 && (z_cmf & 0xf0) <= 0x70)
{
/* Avoid memory underflows and multiplication overflows. */
/* The conditions below are practically always satisfied;
however, they still must be checked. */
if (length >= 2 &&
png_ptr->height < 16384 && png_ptr->width < 16384)
{
png_uint_32 uncompressed_idat_size = png_ptr->height *
(PNG_ROWBYTES(png_ptr->channels*png_ptr->bit_depth,
png_ptr->channels * png_ptr->bit_depth + 15) >> 3);
unsigned int z_cinfo = z_cmf >> 4;
unsigned int half_z_window_size = 1 << (z_cinfo + 7);
while (uncompressed_idat_size <= half_z_window_size &&
half_z_window_size >= 256)
{
z_cinfo--;
half_z_window_size >>= 1;
}
z_cmf = (z_cmf & 0x0f) | (z_cinfo << 4);
if (data[0] != (png_byte)z_cmf)
{
data[0] = (png_byte)z_cmf;
data[1] &= 0xe0;
data[1] += (png_byte)(0x1f - ((z_cmf << 8) + data[1]) % 0x1f);
}
}
}
else
png_error(png_ptr,
"Invalid zlib compression method or flags in IDAT");
}
png_write_chunk(png_ptr, (png_bytep)png_IDAT, data, length);
png_ptr->mode |= PNG_HAVE_IDAT;
}
@@ -1141,7 +1186,12 @@ png_check_keyword(png_structp png_ptr, png_charp key, png_charpp new_key)
png_debug1(2, "Keyword to be checked is '%s'\n", key);
*new_key = (png_charp)png_malloc(png_ptr, (png_uint_32)(key_len + 2));
*new_key = (png_charp)png_malloc_warn(png_ptr, (png_uint_32)(key_len + 2));
if (*new_key == NULL)
{
png_warning(png_ptr, "Out of memory while procesing keyword");
return ((png_size_t)0);
}
/* Replace non-printing characters with a blank and print a warning */
for (kp = key, dp = *new_key; *kp != '\0'; kp++, dp++)
@@ -1353,7 +1403,7 @@ png_write_iTXt(png_structp png_ptr, int compression, png_charp key,
{
png_warning(png_ptr, "Empty language field in iTXt chunk");
new_lang = NULL;
lang_len = 0;
lang_len = 0;
}
if (lang_key == NULL)
@@ -1461,7 +1511,7 @@ png_write_pCAL(png_structp png_ptr, png_charp purpose, png_int_32 X0,
total_len = purpose_len + units_len + 10;
params_len = (png_uint_32p)png_malloc(png_ptr, (png_uint_32)(nparams
*sizeof(png_uint_32)));
*png_sizeof(png_uint_32)));
/* Find the length of each parameter, making sure we don't count the
null terminator for the last parameter. */
@@ -1641,8 +1691,8 @@ png_write_start_row(png_structp png_ptr)
png_size_t buf_size;
png_debug(1, "in png_write_start_row\n");
buf_size = (png_size_t)(((png_ptr->width * png_ptr->usr_channels *
png_ptr->usr_bit_depth + 7) >> 3) + 1);
buf_size = (png_size_t)(PNG_ROWBYTES(
png_ptr->usr_channels*png_ptr->usr_bit_depth,png_ptr->width)+1);
/* set up row buffer */
png_ptr->row_buf = (png_bytep)png_malloc(png_ptr, (png_uint_32)buf_size);
@@ -1778,9 +1828,8 @@ png_write_finish_row(png_structp png_ptr)
{
if (png_ptr->prev_row != NULL)
png_memset(png_ptr->prev_row, 0,
(png_size_t) (((png_uint_32)png_ptr->usr_channels *
(png_uint_32)png_ptr->usr_bit_depth *
png_ptr->width + 7) >> 3) + 1);
(png_size_t)(PNG_ROWBYTES(png_ptr->usr_channels*
png_ptr->usr_bit_depth,png_ptr->width))+1);
return;
}
}
@@ -1987,8 +2036,8 @@ 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 = PNG_ROWBYTES(row_info->pixel_depth,
row_info->width);
}
}
#endif
@@ -2014,7 +2063,7 @@ png_write_find_filter(png_structp png_ptr, png_row_infop row_info)
png_debug(1, "in png_write_find_filter\n");
/* find out how many bytes offset each pixel is */
bpp = (row_info->pixel_depth + 7) / 8;
bpp = (row_info->pixel_depth + 7) >> 3;
prev_row = png_ptr->prev_row;
best_row = row_buf = png_ptr->row_buf;
@@ -2165,7 +2214,7 @@ 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;
for (lp = row_buf + 1; i < row_bytes;
i++, rp++, lp++, dp++)
{
v = *dp = (png_byte)(((int)*rp - (int)*lp) & 0xff);