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Backport pngvalid.c from libpng17

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One fix is required for libpng16 LE, more for libpng16 BE

Signed-off-by: John Bowler <jbowler@acm.org>
This commit is contained in:
John Bowler 2015-12-13 17:07:36 -08:00
parent 975cbbb029
commit cbe5d34f6f
1 changed files with 97 additions and 56 deletions
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91
contrib/libtests/pngvalid.c
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@ -1,7 +1,7 @@
/* pngvalid.c - validate libpng by constructing then reading png files. /* pngvalid.c - validate libpng by constructing then reading png files.
* *
* Last changed in libpng 1.5.25 [(PENDING RELEASE)] * Last changed in libpng 1.5.25 [RDATE%]
* Copyright (c) 2014-2015 Glenn Randers-Pehrson * Copyright (c) 2014-2015 Glenn Randers-Pehrson
* Written by John Cunningham Bowler * Written by John Cunningham Bowler
* *
@ -276,7 +276,8 @@ make_four_random_bytes(png_uint_32* seed, png_bytep bytes)
make_random_bytes(seed, bytes, 4); make_random_bytes(seed, bytes, 4);
} }
#if defined PNG_READ_SUPPORTED || defined PNG_WRITE_tRNS_SUPPORTED #if defined PNG_READ_SUPPORTED || defined PNG_WRITE_tRNS_SUPPORTED ||\
defined PNG_WRITE_FILTER_SUPPORTED
static void static void
randomize(void *pv, size_t size) randomize(void *pv, size_t size)
{ {
@ -285,7 +286,7 @@ randomize(void *pv, size_t size)
} }
#define RANDOMIZE(this) randomize(&(this), sizeof (this)) #define RANDOMIZE(this) randomize(&(this), sizeof (this))
#endif /* READ || WRITE_tRNS */ #endif /* READ || WRITE_tRNS || WRITE_FILTER */
#ifdef PNG_READ_TRANSFORMS_SUPPORTED #ifdef PNG_READ_TRANSFORMS_SUPPORTED
static unsigned int static unsigned int
@ -309,8 +310,8 @@ random_choice(void)
return x & 1; return x & 1;
} }
#endif #endif /* READ_RGB_TO_GRAY || READ_FILLER */
#endif /* PNG_READ_SUPPORTED */ #endif /* READ_TRANSFORMS */
/* A numeric ID based on PNG file characteristics. The 'do_interlace' field /* A numeric ID based on PNG file characteristics. The 'do_interlace' field
* simply records whether pngvalid did the interlace itself or whether it * simply records whether pngvalid did the interlace itself or whether it
@ -3649,6 +3650,31 @@ deinterlace_row(png_bytep buffer, png_const_bytep row,
* layout details. See make_size_images below for a way to make images * layout details. See make_size_images below for a way to make images
* that test odd sizes along with the libpng interlace handling. * that test odd sizes along with the libpng interlace handling.
*/ */
#ifdef PNG_WRITE_FILTER_SUPPORTED
static void
choose_random_filter(png_structp pp, int start)
{
/* Choose filters randomly except that on the very first row ensure that
* there is at least one previous row filter.
*/
int filters;
RANDOMIZE(filters);
filters &= PNG_ALL_FILTERS;
/* There may be no filters; skip the setting. */
if (filters != 0)
{
if (start && filters < PNG_FILTER_UP)
filters |= PNG_FILTER_UP;
png_set_filter(pp, 0/*method*/, filters);
}
}
#else /* !WRITE_FILTER */
# define choose_random_filter(pp, start) ((void)0)
#endif /* !WRITE_FILTER */
static void static void
make_transform_image(png_store* const ps, png_byte const colour_type, make_transform_image(png_store* const ps, png_byte const colour_type,
png_byte const bit_depth, unsigned int palette_number, png_byte const bit_depth, unsigned int palette_number,
@ -3767,6 +3793,7 @@ make_transform_image(png_store* const ps, png_byte const colour_type,
} }
# endif /* do_own_interlace */ # endif /* do_own_interlace */
choose_random_filter(pp, pass == 0 && y == 0);
png_write_row(pp, buffer); png_write_row(pp, buffer);
} }
} }
@ -3943,9 +3970,6 @@ make_size_image(png_store* const ps, png_byte const colour_type,
int npasses = npasses_from_interlace_type(pp, interlace_type); int npasses = npasses_from_interlace_type(pp, interlace_type);
png_uint_32 y; png_uint_32 y;
int pass; int pass;
# ifdef PNG_WRITE_FILTER_SUPPORTED
int nfilter = PNG_FILTER_VALUE_LAST;
# endif
png_byte image[16][SIZE_ROWMAX]; png_byte image[16][SIZE_ROWMAX];
/* To help consistent error detection make the parts of this buffer /* To help consistent error detection make the parts of this buffer
@ -4008,15 +4032,23 @@ make_size_image(png_store* const ps, png_byte const colour_type,
* does accept a filter number (per the spec) as well as a bit * does accept a filter number (per the spec) as well as a bit
* mask. * mask.
* *
* The apparent wackiness of decrementing nfilter rather than * The code now uses filters at random, except that on the first
* incrementing is so that Paeth gets used in all images bigger * row of an image it ensures that a previous row filter is in
* than 1 row - it's the tricky one. * the set so that libpng allocates the row buffer.
*/ */
png_set_filter(pp, 0/*method*/, {
nfilter >= PNG_FILTER_VALUE_LAST ? PNG_ALL_FILTERS : nfilter); int filters;
if (nfilter-- == 0) RANDOMIZE(filters);
nfilter = PNG_FILTER_VALUE_LAST-1; filters %= PNG_FILTER_VALUE_LAST;
if (filters < 0) filters = -filters;
filters = 8 << filters;
if (pass == 0 && y == 0 && filters < PNG_FILTER_UP)
filters |= PNG_FILTER_UP;
png_set_filter(pp, 0/*method*/, filters);
}
# endif # endif
png_write_row(pp, row); png_write_row(pp, row);
@ -4244,11 +4276,17 @@ make_error(png_store* const ps, png_byte const colour_type,
#undef exception__env #undef exception__env
/* And clear these flags */ /* And clear these flags */
ps->expect_error = 0;
ps->expect_warning = 0; ps->expect_warning = 0;
if (ps->expect_error)
ps->expect_error = 0;
else
{
/* Now write the whole image, just to make sure that the detected, or /* Now write the whole image, just to make sure that the detected, or
* undetected, errro has not created problems inside libpng. * undetected, errro has not created problems inside libpng. This
* doesn't work if there was a png_error in png_write_info because that
* can abort before PLTE was written.
*/ */
if (png_get_rowbytes(pp, pi) != if (png_get_rowbytes(pp, pi) !=
transform_rowsize(pp, colour_type, bit_depth)) transform_rowsize(pp, colour_type, bit_depth))
@ -4273,16 +4311,18 @@ make_error(png_store* const ps, png_byte const colour_type,
transform_row(pp, buffer, colour_type, bit_depth, y); transform_row(pp, buffer, colour_type, bit_depth, y);
# if do_own_interlace # if do_own_interlace
/* If do_own_interlace *and* the image is interlaced we need a /* If do_own_interlace *and* the image is interlaced we
* reduced interlace row; this may be reduced to empty. * need a reduced interlace row; this may be reduced to
* empty.
*/ */
if (interlace_type == PNG_INTERLACE_ADAM7) if (interlace_type == PNG_INTERLACE_ADAM7)
{ {
/* The row must not be written if it doesn't exist, notice /* The row must not be written if it doesn't exist,
* that there are two conditions here, either the row isn't * notice that there are two conditions here, either the
* ever in the pass or the row would be but isn't wide * row isn't ever in the pass or the row would be but
* enough to contribute any pixels. In fact the wPass test * isn't wide enough to contribute any pixels. In fact
* can be used to skip the whole y loop in this case. * the wPass test can be used to skip the whole y loop
* in this case.
*/ */
if (PNG_ROW_IN_INTERLACE_PASS(y, pass) && if (PNG_ROW_IN_INTERLACE_PASS(y, pass) &&
PNG_PASS_COLS(w, pass) > 0) PNG_PASS_COLS(w, pass) > 0)
@ -4297,9 +4337,10 @@ make_error(png_store* const ps, png_byte const colour_type,
png_write_row(pp, buffer); png_write_row(pp, buffer);
} }
} }
} } /* image writing */
png_write_end(pp, pi); png_write_end(pp, pi);
}
/* The following deletes the file that was just written. */ /* The following deletes the file that was just written. */
store_write_reset(ps); store_write_reset(ps);