mewin/libpng
1
0
Fork 0
mirror of https://git.code.sf.net/p/libpng/code.git synced 2025-07-10 18:04:09 +02:00
Code Issues Projects Releases Wiki Activity

[libpng16] Made read 'inflate' handling like write 'deflate' handling. The

Browse Source 
read code now claims and releases png_ptr->zstream, like the write code.
The bug whereby the progressive reader failed to release the zstream
is now fixed, all initialization is delayed, and the code checks for
changed parameters on deflate rather than always calling
deflatedEnd/deflateInit.
This commit is contained in:
John Bowler
2012-03-05 20:57:40 -06:00
committed by Glenn Randers-Pehrson
parent e2ae0f2f2b
commit 42a2b556e9
10 changed files with 360 additions and 340 deletions
Download Patch File Download Diff File Expand all files Collapse all files

69
pngwrite.c
View File

@@ -472,6 +472,23 @@ png_create_write_struct_2,(png_const_charp user_png_ver, png_voidp error_ptr,
error_fn, warn_fn, mem_ptr, malloc_fn, free_fn);
#endif /* PNG_USER_MEM_SUPPORTED */
/* Set the zlib control values to defaults; they can be overridden by the
* application after the struct has been created.
*/
png_ptr->zlib_strategy = Z_FILTERED; /* may be overridden if no filters */
png_ptr->zlib_level = Z_DEFAULT_COMPRESSION;
png_ptr->zlib_mem_level = 8;
png_ptr->zlib_window_bits = 15;
png_ptr->zlib_method = 8;
#ifdef PNG_WRITE_COMPRESSED_TEXT_SUPPORTED
png_ptr->zlib_text_strategy = Z_DEFAULT_STRATEGY;
png_ptr->zlib_text_level = Z_DEFAULT_COMPRESSION;
png_ptr->zlib_text_mem_level = 8;
png_ptr->zlib_text_window_bits = 15;
png_ptr->zlib_text_method = 8;
#endif /* PNG_WRITE_COMPRESSED_TEXT_SUPPORTED */
if (png_ptr != NULL)
{
/* TODO: delay this, it can be done in png_init_io() (if the app doesn't
@@ -827,7 +844,7 @@ png_write_destroy(png_structrp png_ptr)
png_debug(1, "in png_write_destroy");
/* Free any memory zlib uses */
if (png_ptr->zlib_state != PNG_ZLIB_UNINITIALIZED)
if (png_ptr->flags & PNG_FLAG_ZSTREAM_INITIALIZED)
deflateEnd(&png_ptr->zstream);
/* Free our memory. png_free checks NULL for us. */
@@ -1266,7 +1283,6 @@ png_set_compression_level(png_structrp png_ptr, int level)
if (png_ptr == NULL)
return;
png_ptr->flags |= PNG_FLAG_ZLIB_CUSTOM_LEVEL;
png_ptr->zlib_level = level;
}
@@ -1278,7 +1294,6 @@ png_set_compression_mem_level(png_structrp png_ptr, int mem_level)
if (png_ptr == NULL)
return;
png_ptr->flags |= PNG_FLAG_ZLIB_CUSTOM_MEM_LEVEL;
png_ptr->zlib_mem_level = mem_level;
}
@@ -1290,6 +1305,8 @@ png_set_compression_strategy(png_structrp png_ptr, int strategy)
if (png_ptr == NULL)
return;
/* The flag setting here prevents the libpng dynamic selection of strategy.
*/
png_ptr->flags |= PNG_FLAG_ZLIB_CUSTOM_STRATEGY;
png_ptr->zlib_strategy = strategy;
}
@@ -1303,22 +1320,24 @@ png_set_compression_window_bits(png_structrp png_ptr, int window_bits)
if (png_ptr == NULL)
return;
/* Prior to 1.6.0 this would warn but then set the window_bits value, this
* meant that negative window bits values could be selected which would cause
* libpng to write a non-standard PNG file with raw deflate or gzip
* compressed IDAT or ancilliary chunks. Such files can be read and there is
* no warning on read, so this seems like a very bad idea.
*/
if (window_bits > 15)
{
png_warning(png_ptr, "Only compression windows <= 32k supported by PNG");
window_bits = 15;
}
else if (window_bits < 8)
{
png_warning(png_ptr, "Only compression windows >= 256 supported by PNG");
window_bits = 8;
}
#ifndef WBITS_8_OK
/* Avoid libpng bug with 256-byte windows */
if (window_bits == 8)
{
png_warning(png_ptr, "Compression window is being reset to 512");
window_bits = 9;
}
#endif
png_ptr->flags |= PNG_FLAG_ZLIB_CUSTOM_WINDOW_BITS;
png_ptr->zlib_window_bits = window_bits;
}
@@ -1330,10 +1349,12 @@ png_set_compression_method(png_structrp png_ptr, int method)
if (png_ptr == NULL)
return;
/* This would produce an invalid PNG file if it worked, but it doesn't and
* deflate will fault it, so it is harmless to just warn here.
*/
if (method != 8)
png_warning(png_ptr, "Only compression method 8 is supported by PNG");
png_ptr->flags |= PNG_FLAG_ZLIB_CUSTOM_METHOD;
png_ptr->zlib_method = method;
}
@@ -1347,7 +1368,6 @@ png_set_text_compression_level(png_structrp png_ptr, int level)
if (png_ptr == NULL)
return;
png_ptr->flags |= PNG_FLAG_ZTXT_CUSTOM_LEVEL;
png_ptr->zlib_text_level = level;
}
@@ -1359,7 +1379,6 @@ png_set_text_compression_mem_level(png_structrp png_ptr, int mem_level)
if (png_ptr == NULL)
return;
png_ptr->flags |= PNG_FLAG_ZTXT_CUSTOM_MEM_LEVEL;
png_ptr->zlib_text_mem_level = mem_level;
}
@@ -1371,7 +1390,6 @@ png_set_text_compression_strategy(png_structrp png_ptr, int strategy)
if (png_ptr == NULL)
return;
png_ptr->flags |= PNG_FLAG_ZTXT_CUSTOM_STRATEGY;
png_ptr->zlib_text_strategy = strategy;
}
@@ -1385,21 +1403,17 @@ png_set_text_compression_window_bits(png_structrp png_ptr, int window_bits)
return;
if (window_bits > 15)
{
png_warning(png_ptr, "Only compression windows <= 32k supported by PNG");
window_bits = 15;
}
else if (window_bits < 8)
{
png_warning(png_ptr, "Only compression windows >= 256 supported by PNG");
window_bits = 8;
}
#ifndef WBITS_8_OK
/* Avoid libpng bug with 256-byte windows */
if (window_bits == 8)
{
png_warning(png_ptr, "Text compression window is being reset to 512");
window_bits = 9;
}
#endif
png_ptr->flags |= PNG_FLAG_ZTXT_CUSTOM_WINDOW_BITS;
png_ptr->zlib_text_window_bits = window_bits;
}
@@ -1414,7 +1428,6 @@ png_set_text_compression_method(png_structrp png_ptr, int method)
if (method != 8)
png_warning(png_ptr, "Only compression method 8 is supported by PNG");
png_ptr->flags |= PNG_FLAG_ZTXT_CUSTOM_METHOD;
png_ptr->zlib_text_method = method;
}
#endif /* PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED */