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[master] Imported from libpng-1.6.22.tar

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This commit is contained in:
Glenn Randers-Pehrson
2016-05-25 22:41:46 -05:00
parent 5756fcab2f
commit 87c14c528a
54 changed files with 3023 additions and 526 deletions
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171
pngwrite.c
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@@ -12,9 +12,9 @@
*/
#include "pngpriv.h"
#if defined(PNG_SIMPLIFIED_WRITE_SUPPORTED) && defined(PNG_STDIO_SUPPORTED)
#ifdef PNG_SIMPLIFIED_WRITE_STDIO_SUPPORTED
# include <errno.h>
#endif
#endif /* SIMPLIFIED_WRITE_STDIO */
#ifdef PNG_WRITE_SUPPORTED
@@ -1452,7 +1452,6 @@ png_write_png(png_structrp png_ptr, png_inforp info_ptr,
#ifdef PNG_SIMPLIFIED_WRITE_SUPPORTED
# ifdef PNG_STDIO_SUPPORTED /* currently required for png_image_write_* */
/* Initialize the write structure - general purpose utility. */
static int
png_image_write_init(png_imagep image)
@@ -1504,6 +1503,10 @@ typedef struct
png_const_voidp first_row;
ptrdiff_t row_bytes;
png_voidp local_row;
/* Byte count for memory writing */
png_bytep memory;
png_alloc_size_t memory_bytes; /* not used for STDIO */
png_alloc_size_t output_bytes; /* running total */
} png_image_write_control;
/* Write png_uint_16 input to a 16-bit PNG; the png_ptr has already been set to
@@ -1931,9 +1934,43 @@ png_image_write_main(png_voidp argument)
png_set_benign_errors(png_ptr, 0/*error*/);
# endif
/* Default the 'row_stride' parameter if required. */
if (display->row_stride == 0)
display->row_stride = PNG_IMAGE_ROW_STRIDE(*image);
/* Default the 'row_stride' parameter if required, also check the row stride
* and total image size to ensure that they are within the system limits.
*/
{
const unsigned int channels = PNG_IMAGE_PIXEL_CHANNELS(image->format);
if (image->width <= 0x7FFFFFFFU/channels) /* no overflow */
{
png_uint_32 check;
const png_uint_32 png_row_stride = image->width * channels;
if (display->row_stride == 0)
display->row_stride = (png_int_32)/*SAFE*/png_row_stride;
if (display->row_stride < 0)
check = -display->row_stride;
else
check = display->row_stride;
if (check >= png_row_stride)
{
/* Now check for overflow of the image buffer calculation; this
* limits the whole image size to 32 bits for API compatibility with
* the current, 32-bit, PNG_IMAGE_BUFFER_SIZE macro.
*/
if (image->height > 0xFFFFFFFF/png_row_stride)
png_error(image->opaque->png_ptr, "memory image too large");
}
else
png_error(image->opaque->png_ptr, "supplied row stride too small");
}
else
png_error(image->opaque->png_ptr, "image row stride too large");
}
/* Set the required transforms then write the rows in the correct order. */
if ((format & PNG_FORMAT_FLAG_COLORMAP) != 0)
@@ -2110,6 +2147,122 @@ png_image_write_main(png_voidp argument)
return 1;
}
static void (PNGCBAPI
image_memory_write)(png_structp png_ptr, png_bytep/*const*/ data,
png_size_t size)
{
png_image_write_control *display = png_voidcast(png_image_write_control*,
png_ptr->io_ptr/*backdoor: png_get_io_ptr(png_ptr)*/);
const png_alloc_size_t ob = display->output_bytes;
/* Check for overflow; this should never happen: */
if (size <= ((png_alloc_size_t)-1) - ob)
{
/* I don't think libpng ever does this, but just in case: */
if (size > 0)
{
if (display->memory_bytes >= ob+size) /* writing */
memcpy(display->memory+ob, data, size);
/* Always update the size: */
display->output_bytes = ob+size;
}
}
else
png_error(png_ptr, "png_image_write_to_memory: PNG too big");
}
static void (PNGCBAPI
image_memory_flush)(png_structp png_ptr)
{
PNG_UNUSED(png_ptr)
}
static int
png_image_write_memory(png_voidp argument)
{
png_image_write_control *display = png_voidcast(png_image_write_control*,
argument);
/* The rest of the memory-specific init and write_main in an error protected
* environment. This case needs to use callbacks for the write operations
* since libpng has no built in support for writing to memory.
*/
png_set_write_fn(display->image->opaque->png_ptr, display/*io_ptr*/,
image_memory_write, image_memory_flush);
return png_image_write_main(display);
}
int PNGAPI
png_image_write_to_memory(png_imagep image, void *memory,
png_alloc_size_t * PNG_RESTRICT memory_bytes, int convert_to_8bit,
const void *buffer, png_int_32 row_stride, const void *colormap)
{
/* Write the image to the given buffer, or count the bytes if it is NULL */
if (image != NULL && image->version == PNG_IMAGE_VERSION)
{
if (memory_bytes != NULL && buffer != NULL)
{
/* This is to give the caller an easier error detection in the NULL
* case and guard against uninitialized variable problems:
*/
if (memory == NULL)
*memory_bytes = 0;
if (png_image_write_init(image) != 0)
{
png_image_write_control display;
int result;
memset(&display, 0, (sizeof display));
display.image = image;
display.buffer = buffer;
display.row_stride = row_stride;
display.colormap = colormap;
display.convert_to_8bit = convert_to_8bit;
display.memory = png_voidcast(png_bytep, memory);
display.memory_bytes = *memory_bytes;
display.output_bytes = 0;
result = png_safe_execute(image, png_image_write_memory, &display);
png_image_free(image);
/* write_memory returns true even if we ran out of buffer. */
if (result)
{
/* On out-of-buffer this function returns '0' but still updates
* memory_bytes:
*/
if (memory != NULL && display.output_bytes > *memory_bytes)
result = 0;
*memory_bytes = display.output_bytes;
}
return result;
}
else
return 0;
}
else
return png_image_error(image,
"png_image_write_to_memory: invalid argument");
}
else if (image != NULL)
return png_image_error(image,
"png_image_write_to_memory: incorrect PNG_IMAGE_VERSION");
else
return 0;
}
#ifdef PNG_SIMPLIFIED_WRITE_STDIO_SUPPORTED
int PNGAPI
png_image_write_to_stdio(png_imagep image, FILE *file, int convert_to_8bit,
const void *buffer, png_int_32 row_stride, const void *colormap)
@@ -2117,7 +2270,7 @@ png_image_write_to_stdio(png_imagep image, FILE *file, int convert_to_8bit,
/* Write the image to the given (FILE*). */
if (image != NULL && image->version == PNG_IMAGE_VERSION)
{
if (file != NULL)
if (file != NULL && buffer != NULL)
{
if (png_image_write_init(image) != 0)
{
@@ -2167,7 +2320,7 @@ png_image_write_to_file(png_imagep image, const char *file_name,
/* Write the image to the named file. */
if (image != NULL && image->version == PNG_IMAGE_VERSION)
{
if (file_name != NULL)
if (file_name != NULL && buffer != NULL)
{
FILE *fp = fopen(file_name, "wb");
@@ -2225,6 +2378,6 @@ png_image_write_to_file(png_imagep image, const char *file_name,
else
return 0;
}
# endif /* STDIO */
#endif /* SIMPLIFIED_WRITE_STDIO */
#endif /* SIMPLIFIED_WRITE */
#endif /* WRITE */