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pngtest.c
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pngtest.c
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/* pngtest.c - a simple test program to test libpng
*
* Last changed in libpng 1.6.11 [June 12, 2014]
* Copyright (c) 1998-2014 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.)
*
* This code is released under the libpng license.
* For conditions of distribution and use, see the disclaimer
* and license in png.h
*
* This program reads in a PNG image, writes it out again, and then
* compares the two files. If the files are identical, this shows that
* the basic chunk handling, filtering, and (de)compression code is working
* properly. It does not currently test all of the transforms, although
* it probably should.
*
* The program will report "FAIL" in certain legitimate cases:
* 1) when the compression level or filter selection method is changed.
* 2) when the maximum IDAT size (PNG_ZBUF_SIZE in pngconf.h) is not 8192.
* 3) unknown unsafe-to-copy ancillary chunks or unknown critical chunks
* exist in the input file.
* 4) others not listed here...
* In these cases, it is best to check with another tool such as "pngcheck"
* to see what the differences between the two files are.
*
* If a filename is given on the command-line, then this file is used
* for the input, rather than the default "pngtest.png". This allows
* testing a wide variety of files easily. You can also test a number
* of files at once by typing "pngtest -m file1.png file2.png ..."
*/
#define _POSIX_SOURCE 1
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
/* Defined so I can write to a file on gui/windowing platforms */
/* #define STDERR stderr */
#define STDERR stdout /* For DOS */
#include "png.h"
/* Known chunks that exist in pngtest.png must be supported or pngtest will fail
* simply as a result of re-ordering them. This may be fixed in 1.7
*
* pngtest allocates a single row buffer for each row and overwrites it,
* therefore if the write side doesn't support the writing of interlaced images
* nothing can be done for an interlaced image (and the code below will fail
* horribly trying to write extra data after writing garbage).
*/
#if defined PNG_READ_SUPPORTED && /* else nothing can be done */\
defined PNG_READ_bKGD_SUPPORTED &&\
defined PNG_READ_cHRM_SUPPORTED &&\
defined PNG_READ_gAMA_SUPPORTED &&\
defined PNG_READ_oFFs_SUPPORTED &&\
defined PNG_READ_pCAL_SUPPORTED &&\
defined PNG_READ_pHYs_SUPPORTED &&\
defined PNG_READ_sBIT_SUPPORTED &&\
defined PNG_READ_sCAL_SUPPORTED &&\
defined PNG_READ_sRGB_SUPPORTED &&\
defined PNG_READ_tEXt_SUPPORTED &&\
defined PNG_READ_tIME_SUPPORTED &&\
defined PNG_READ_zTXt_SUPPORTED &&\
defined PNG_WRITE_INTERLACING_SUPPORTED
#ifdef PNG_ZLIB_HEADER
# include PNG_ZLIB_HEADER /* defined by pnglibconf.h from 1.7 */
#else
# include "zlib.h"
#endif
/* Copied from pngpriv.h but only used in error messages below. */
#ifndef PNG_ZBUF_SIZE
# define PNG_ZBUF_SIZE 8192
#endif
#define FCLOSE(file) fclose(file)
#ifndef PNG_STDIO_SUPPORTED
typedef FILE * png_FILE_p;
#endif
/* Makes pngtest verbose so we can find problems. */
#ifndef PNG_DEBUG
# define PNG_DEBUG 0
#endif
#if PNG_DEBUG > 1
# define pngtest_debug(m) ((void)fprintf(stderr, m "\n"))
# define pngtest_debug1(m,p1) ((void)fprintf(stderr, m "\n", p1))
# define pngtest_debug2(m,p1,p2) ((void)fprintf(stderr, m "\n", p1, p2))
#else
# define pngtest_debug(m) ((void)0)
# define pngtest_debug1(m,p1) ((void)0)
# define pngtest_debug2(m,p1,p2) ((void)0)
#endif
#if !PNG_DEBUG
# define SINGLE_ROWBUF_ALLOC /* Makes buffer overruns easier to nail */
#endif
/* Turn on CPU timing
#define PNGTEST_TIMING
*/
#ifndef PNG_FLOATING_POINT_SUPPORTED
#undef PNGTEST_TIMING
#endif
#ifdef PNGTEST_TIMING
static float t_start, t_stop, t_decode, t_encode, t_misc;
#include <time.h>
#endif
#ifdef PNG_TIME_RFC1123_SUPPORTED
#define PNG_tIME_STRING_LENGTH 29
static int tIME_chunk_present = 0;
static char tIME_string[PNG_tIME_STRING_LENGTH] = "tIME chunk is not present";
#endif
static int verbose = 0;
static int strict = 0;
static int relaxed = 0;
static int unsupported_chunks = 0; /* chunk unsupported by libpng in input */
static int error_count = 0; /* count calls to png_error */
static int warning_count = 0; /* count calls to png_warning */
/* Define png_jmpbuf() in case we are using a pre-1.0.6 version of libpng */
#ifndef png_jmpbuf
# define png_jmpbuf(png_ptr) png_ptr->jmpbuf
#endif
/* Defines for unknown chunk handling if required. */
#ifndef PNG_HANDLE_CHUNK_ALWAYS
# define PNG_HANDLE_CHUNK_ALWAYS 3
#endif
#ifndef PNG_HANDLE_CHUNK_IF_SAFE
# define PNG_HANDLE_CHUNK_IF_SAFE 2
#endif
/* Utility to save typing/errors, the argument must be a name */
#define MEMZERO(var) ((void)memset(&var, 0, sizeof var))
/* Example of using row callbacks to make a simple progress meter */
static int status_pass = 1;
static int status_dots_requested = 0;
static int status_dots = 1;
static void PNGCBAPI
read_row_callback(png_structp png_ptr, png_uint_32 row_number, int pass)
{
if (png_ptr == NULL || row_number > PNG_UINT_31_MAX)
return;
if (status_pass != pass)
{
fprintf(stdout, "\n Pass %d: ", pass);
status_pass = pass;
status_dots = 31;
}
status_dots--;
if (status_dots == 0)
{
fprintf(stdout, "\n ");
status_dots=30;
}
fprintf(stdout, "r");
}
#ifdef PNG_WRITE_SUPPORTED
static void PNGCBAPI
write_row_callback(png_structp png_ptr, png_uint_32 row_number, int pass)
{
if (png_ptr == NULL || row_number > PNG_UINT_31_MAX || pass > 7)
return;
fprintf(stdout, "w");
}
#endif
#ifdef PNG_READ_USER_TRANSFORM_SUPPORTED
/* Example of using user transform callback (we don't transform anything,
* but merely examine the row filters. We set this to 256 rather than
* 5 in case illegal filter values are present.)
*/
static png_uint_32 filters_used[256];
static void PNGCBAPI
count_filters(png_structp png_ptr, png_row_infop row_info, png_bytep data)
{
if (png_ptr != NULL && row_info != NULL)
++filters_used[*(data - 1)];
}
#endif
#ifdef PNG_WRITE_USER_TRANSFORM_SUPPORTED
/* Example of using user transform callback (we don't transform anything,
* but merely count the zero samples)
*/
static png_uint_32 zero_samples;
static void PNGCBAPI
count_zero_samples(png_structp png_ptr, png_row_infop row_info, png_bytep data)
{
png_bytep dp = data;
if (png_ptr == NULL)
return;
/* Contents of row_info:
* png_uint_32 width width of row
* png_uint_32 rowbytes number of bytes in row
* png_byte color_type color type of pixels
* png_byte bit_depth bit depth of samples
* png_byte channels number of channels (1-4)
* png_byte pixel_depth bits per pixel (depth*channels)
*/
/* Counts the number of zero samples (or zero pixels if color_type is 3 */
if (row_info->color_type == 0 || row_info->color_type == 3)
{
int pos = 0;
png_uint_32 n, nstop;
for (n = 0, nstop=row_info->width; n<nstop; n++)
{
if (row_info->bit_depth == 1)
{
if (((*dp << pos++ ) & 0x80) == 0)
zero_samples++;
if (pos == 8)
{
pos = 0;
dp++;
}
}
if (row_info->bit_depth == 2)
{
if (((*dp << (pos+=2)) & 0xc0) == 0)
zero_samples++;
if (pos == 8)
{
pos = 0;
dp++;
}
}
if (row_info->bit_depth == 4)
{
if (((*dp << (pos+=4)) & 0xf0) == 0)
zero_samples++;
if (pos == 8)
{
pos = 0;
dp++;
}
}
if (row_info->bit_depth == 8)
if (*dp++ == 0)
zero_samples++;
if (row_info->bit_depth == 16)
{
if ((*dp | *(dp+1)) == 0)
zero_samples++;
dp+=2;
}
}
}
else /* Other color types */
{
png_uint_32 n, nstop;
int channel;
int color_channels = row_info->channels;
if (row_info->color_type > 3)color_channels--;
for (n = 0, nstop=row_info->width; n<nstop; n++)
{
for (channel = 0; channel < color_channels; channel++)
{
if (row_info->bit_depth == 8)
if (*dp++ == 0)
zero_samples++;
if (row_info->bit_depth == 16)
{
if ((*dp | *(dp+1)) == 0)
zero_samples++;
dp+=2;
}
}
if (row_info->color_type > 3)
{
dp++;
if (row_info->bit_depth == 16)
dp++;
}
}
}
}
#endif /* PNG_WRITE_USER_TRANSFORM_SUPPORTED */
#ifndef PNG_STDIO_SUPPORTED
/* START of code to validate stdio-free compilation */
/* These copies of the default read/write functions come from pngrio.c and
* pngwio.c. They allow "don't include stdio" testing of the library.
* This is the function that does the actual reading of data. If you are
* not reading from a standard C stream, you should create a replacement
* read_data function and use it at run time with png_set_read_fn(), rather
* than changing the library.
*/
#ifdef PNG_IO_STATE_SUPPORTED
void
pngtest_check_io_state(png_structp png_ptr, png_size_t data_length,
png_uint_32 io_op);
void
pngtest_check_io_state(png_structp png_ptr, png_size_t data_length,
png_uint_32 io_op)
{
png_uint_32 io_state = png_get_io_state(png_ptr);
int err = 0;
/* Check if the current operation (reading / writing) is as expected. */
if ((io_state & PNG_IO_MASK_OP) != io_op)
png_error(png_ptr, "Incorrect operation in I/O state");
/* Check if the buffer size specific to the current location
* (file signature / header / data / crc) is as expected.
*/
switch (io_state & PNG_IO_MASK_LOC)
{
case PNG_IO_SIGNATURE:
if (data_length > 8)
err = 1;
break;
case PNG_IO_CHUNK_HDR:
if (data_length != 8)
err = 1;
break;
case PNG_IO_CHUNK_DATA:
break; /* no restrictions here */
case PNG_IO_CHUNK_CRC:
if (data_length != 4)
err = 1;
break;
default:
err = 1; /* uninitialized */
}
if (err != 0)
png_error(png_ptr, "Bad I/O state or buffer size");
}
#endif
static void PNGCBAPI
pngtest_read_data(png_structp png_ptr, png_bytep data, png_size_t length)
{
png_size_t check = 0;
png_voidp io_ptr;
/* fread() returns 0 on error, so it is OK to store this in a png_size_t
* instead of an int, which is what fread() actually returns.
*/
io_ptr = png_get_io_ptr(png_ptr);
if (io_ptr != NULL)
{
check = fread(data, 1, length, (png_FILE_p)io_ptr);
}
if (check != length)
{
png_error(png_ptr, "Read Error");
}
#ifdef PNG_IO_STATE_SUPPORTED
pngtest_check_io_state(png_ptr, length, PNG_IO_READING);
#endif
}
#ifdef PNG_WRITE_FLUSH_SUPPORTED
static void PNGCBAPI
pngtest_flush(png_structp png_ptr)
{
/* Do nothing; fflush() is said to be just a waste of energy. */
PNG_UNUSED(png_ptr) /* Stifle compiler warning */
}
#endif
/* This is the function that does the actual writing of data. If you are
* not writing to a standard C stream, you should create a replacement
* write_data function and use it at run time with png_set_write_fn(), rather
* than changing the library.
*/
static void PNGCBAPI
pngtest_write_data(png_structp png_ptr, png_bytep data, png_size_t length)
{
png_size_t check;
check = fwrite(data, 1, length, (png_FILE_p)png_get_io_ptr(png_ptr));
if (check != length)
{
png_error(png_ptr, "Write Error");
}
#ifdef PNG_IO_STATE_SUPPORTED
pngtest_check_io_state(png_ptr, length, PNG_IO_WRITING);
#endif
}
#endif /* !PNG_STDIO_SUPPORTED */
/* This function is called when there is a warning, but the library thinks
* it can continue anyway. Replacement functions don't have to do anything
* here if you don't want to. In the default configuration, png_ptr is
* not used, but it is passed in case it may be useful.
*/
typedef struct
{
PNG_CONST char *file_name;
} pngtest_error_parameters;
static void PNGCBAPI
pngtest_warning(png_structp png_ptr, png_const_charp message)
{
PNG_CONST char *name = "UNKNOWN (ERROR!)";
pngtest_error_parameters *test =
(pngtest_error_parameters*)png_get_error_ptr(png_ptr);
++warning_count;
if (test != NULL && test->file_name != NULL)
name = test->file_name;
fprintf(STDERR, "%s: libpng warning: %s\n", name, message);
}
/* This is the default error handling function. Note that replacements for
* this function MUST NOT RETURN, or the program will likely crash. This
* function is used by default, or if the program supplies NULL for the
* error function pointer in png_set_error_fn().
*/
static void PNGCBAPI
pngtest_error(png_structp png_ptr, png_const_charp message)
{
++error_count;
pngtest_warning(png_ptr, message);
/* We can return because png_error calls the default handler, which is
* actually OK in this case.
*/
}
/* END of code to validate stdio-free compilation */
/* START of code to validate memory allocation and deallocation */
#if defined(PNG_USER_MEM_SUPPORTED) && PNG_DEBUG
/* Allocate memory. For reasonable files, size should never exceed
* 64K. However, zlib may allocate more then 64K if you don't tell
* it not to. See zconf.h and png.h for more information. zlib does
* need to allocate exactly 64K, so whatever you call here must
* have the ability to do that.
*
* This piece of code can be compiled to validate max 64K allocations
* by setting MAXSEG_64K in zlib zconf.h *or* PNG_MAX_MALLOC_64K.
*/
typedef struct memory_information
{
png_alloc_size_t size;
png_voidp pointer;
struct memory_information *next;
} memory_information;
typedef memory_information *memory_infop;
static memory_infop pinformation = NULL;
static int current_allocation = 0;
static int maximum_allocation = 0;
static int total_allocation = 0;
static int num_allocations = 0;
png_voidp PNGCBAPI png_debug_malloc PNGARG((png_structp png_ptr,
png_alloc_size_t size));
void PNGCBAPI png_debug_free PNGARG((png_structp png_ptr, png_voidp ptr));
png_voidp
PNGCBAPI png_debug_malloc(png_structp png_ptr, png_alloc_size_t size)
{
/* png_malloc has already tested for NULL; png_create_struct calls
* png_debug_malloc directly, with png_ptr == NULL which is OK
*/
if (size == 0)
return (NULL);
/* This calls the library allocator twice, once to get the requested
buffer and once to get a new free list entry. */
{
/* Disable malloc_fn and free_fn */
memory_infop pinfo;
png_set_mem_fn(png_ptr, NULL, NULL, NULL);
pinfo = (memory_infop)png_malloc(png_ptr,
(sizeof *pinfo));
pinfo->size = size;
current_allocation += size;
total_allocation += size;
num_allocations ++;
if (current_allocation > maximum_allocation)
maximum_allocation = current_allocation;
pinfo->pointer = png_malloc(png_ptr, size);
/* Restore malloc_fn and free_fn */
png_set_mem_fn(png_ptr,
NULL, png_debug_malloc, png_debug_free);
if (size != 0 && pinfo->pointer == NULL)
{
current_allocation -= size;
total_allocation -= size;
png_error(png_ptr,
"out of memory in pngtest->png_debug_malloc");
}
pinfo->next = pinformation;
pinformation = pinfo;
/* Make sure the caller isn't assuming zeroed memory. */
memset(pinfo->pointer, 0xdd, pinfo->size);
if (verbose != 0)
printf("png_malloc %lu bytes at %p\n", (unsigned long)size,
pinfo->pointer);
return (png_voidp)(pinfo->pointer);
}
}
/* Free a pointer. It is removed from the list at the same time. */
void PNGCBAPI
png_debug_free(png_structp png_ptr, png_voidp ptr)
{
if (png_ptr == NULL)
fprintf(STDERR, "NULL pointer to png_debug_free.\n");
if (ptr == 0)
{
#if 0 /* This happens all the time. */
fprintf(STDERR, "WARNING: freeing NULL pointer\n");
#endif
return;
}
/* Unlink the element from the list. */
{
memory_infop *ppinfo = &pinformation;
for (;;)
{
memory_infop pinfo = *ppinfo;
if (pinfo->pointer == ptr)
{
*ppinfo = pinfo->next;
current_allocation -= pinfo->size;
if (current_allocation < 0)
fprintf(STDERR, "Duplicate free of memory\n");
/* We must free the list element too, but first kill
the memory that is to be freed. */
memset(ptr, 0x55, pinfo->size);
if (pinfo != NULL)
free(pinfo);
pinfo = NULL;
break;
}
if (pinfo->next == NULL)
{
fprintf(STDERR, "Pointer %x not found\n", (unsigned int)ptr);
break;
}
ppinfo = &pinfo->next;
}
}
/* Finally free the data. */
if (verbose != 0)
printf("Freeing %p\n", ptr);
if (ptr != NULL)
free(ptr);
ptr = NULL;
}
#endif /* PNG_USER_MEM_SUPPORTED && PNG_DEBUG */
/* END of code to test memory allocation/deallocation */
#ifdef PNG_READ_USER_CHUNKS_SUPPORTED
/* Demonstration of user chunk support of the sTER and vpAg chunks */
/* (sTER is a public chunk not yet known by libpng. vpAg is a private
chunk used in ImageMagick to store "virtual page" size). */
static struct user_chunk_data
{
png_const_infop info_ptr;
png_uint_32 vpAg_width, vpAg_height;
png_byte vpAg_units;
png_byte sTER_mode;
int location[2];
}
user_chunk_data;
/* Used for location and order; zero means nothing. */
#define have_sTER 0x01
#define have_vpAg 0x02
#define before_PLTE 0x10
#define before_IDAT 0x20
#define after_IDAT 0x40
static void
init_callback_info(png_const_infop info_ptr)
{
MEMZERO(user_chunk_data);
user_chunk_data.info_ptr = info_ptr;
}
static int
set_location(png_structp png_ptr, struct user_chunk_data *data, int what)
{
int location;
if ((data->location[0] & what) || (data->location[1] & what))
return 0; /* already have one of these */
/* Find where we are (the code below zeros info_ptr to indicate that the
* chunks before the first IDAT have been read.)
*/
if (data->info_ptr == NULL) /* after IDAT */
location = what | after_IDAT;
else if (png_get_valid(png_ptr, data->info_ptr, PNG_INFO_PLTE))
location = what | before_IDAT;
else
location = what | before_PLTE;
if (data->location[0] == 0)
data->location[0] = location;
else
data->location[1] = location;
return 1; /* handled */
}
static int PNGCBAPI
read_user_chunk_callback(png_struct *png_ptr, png_unknown_chunkp chunk)
{
struct user_chunk_data *my_user_chunk_data =
(struct user_chunk_data*)png_get_user_chunk_ptr(png_ptr);
if (my_user_chunk_data == NULL)
png_error(png_ptr, "lost user chunk pointer");
/* Return one of the following:
* return (-n); chunk had an error
* return (0); did not recognize
* return (n); success
*
* The unknown chunk structure contains the chunk data:
* png_byte name[5];
* png_byte *data;
* png_size_t size;
*
* Note that libpng has already taken care of the CRC handling.
*/
if (chunk->name[0] == 115 && chunk->name[1] == 84 && /* s T */
chunk->name[2] == 69 && chunk->name[3] == 82) /* E R */
{
/* Found sTER chunk */
if (chunk->size != 1)
return (-1); /* Error return */
if (chunk->data[0] != 0 && chunk->data[0] != 1)
return (-1); /* Invalid mode */
if (set_location(png_ptr, my_user_chunk_data, have_sTER))
{
my_user_chunk_data->sTER_mode=chunk->data[0];
return (1);
}
else
return (0); /* duplicate sTER - give it to libpng */
}
if (chunk->name[0] != 118 || chunk->name[1] != 112 || /* v p */
chunk->name[2] != 65 || chunk->name[3] != 103) /* A g */
return (0); /* Did not recognize */
/* Found ImageMagick vpAg chunk */
if (chunk->size != 9)
return (-1); /* Error return */
if (!set_location(png_ptr, my_user_chunk_data, have_vpAg))
return (0); /* duplicate vpAg */
my_user_chunk_data->vpAg_width = png_get_uint_31(png_ptr, chunk->data);
my_user_chunk_data->vpAg_height = png_get_uint_31(png_ptr, chunk->data + 4);
my_user_chunk_data->vpAg_units = chunk->data[8];
return (1);
}
#ifdef PNG_WRITE_SUPPORTED
static void
write_sTER_chunk(png_structp write_ptr)
{
png_byte sTER[5] = {115, 84, 69, 82, '\0'};
if (verbose != 0)
fprintf(STDERR, "\n stereo mode = %d\n", user_chunk_data.sTER_mode);
png_write_chunk(write_ptr, sTER, &user_chunk_data.sTER_mode, 1);
}
static void
write_vpAg_chunk(png_structp write_ptr)
{
png_byte vpAg[5] = {118, 112, 65, 103, '\0'};
png_byte vpag_chunk_data[9];
if (verbose != 0)
fprintf(STDERR, " vpAg = %lu x %lu, units = %d\n",
(unsigned long)user_chunk_data.vpAg_width,
(unsigned long)user_chunk_data.vpAg_height,
user_chunk_data.vpAg_units);
png_save_uint_32(vpag_chunk_data, user_chunk_data.vpAg_width);
png_save_uint_32(vpag_chunk_data + 4, user_chunk_data.vpAg_height);
vpag_chunk_data[8] = user_chunk_data.vpAg_units;
png_write_chunk(write_ptr, vpAg, vpag_chunk_data, 9);
}
static void
write_chunks(png_structp write_ptr, int location)
{
int i;
/* Notice that this preserves the original chunk order, however chunks
* intercepted by the callback will be written *after* chunks passed to
* libpng. This will actually reverse a pair of sTER chunks or a pair of
* vpAg chunks, resulting in an error later. This is not worth worrying
* about - the chunks should not be duplicated!
*/
for (i=0; i<2; ++i)
{
if (user_chunk_data.location[i] == (location | have_sTER))
write_sTER_chunk(write_ptr);
else if (user_chunk_data.location[i] == (location | have_vpAg))
write_vpAg_chunk(write_ptr);
}
}
#endif /* PNG_WRITE_SUPPORTED */
#else /* !PNG_READ_USER_CHUNKS_SUPPORTED */
# define write_chunks(pp,loc) ((void)0)
#endif
/* END of code to demonstrate user chunk support */
/* START of code to check that libpng has the required text support; this only
* checks for the write support because if read support is missing the chunk
* will simply not be reported back to pngtest.
*/
#ifdef PNG_TEXT_SUPPORTED
static void
pngtest_check_text_support(png_const_structp png_ptr, png_textp text_ptr,
int num_text)
{
while (num_text > 0)
{
switch (text_ptr[--num_text].compression)
{
case PNG_TEXT_COMPRESSION_NONE:
break;
case PNG_TEXT_COMPRESSION_zTXt:
# ifndef PNG_WRITE_zTXt_SUPPORTED
++unsupported_chunks;
# endif
break;
case PNG_ITXT_COMPRESSION_NONE:
case PNG_ITXT_COMPRESSION_zTXt:
# ifndef PNG_WRITE_iTXt_SUPPORTED
++unsupported_chunks;
# endif
break;
default:
/* This is an error */
png_error(png_ptr, "invalid text chunk compression field");
break;
}
}
}
#endif
/* END of code to check that libpng has the required text support */
/* Test one file */
static int
test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
{
static png_FILE_p fpin;
static png_FILE_p fpout; /* "static" prevents setjmp corruption */
pngtest_error_parameters error_parameters;
png_structp read_ptr;
png_infop read_info_ptr, end_info_ptr;
#ifdef PNG_WRITE_SUPPORTED
png_structp write_ptr;
png_infop write_info_ptr;
png_infop write_end_info_ptr;
int interlace_preserved = 1;
#else
png_structp write_ptr = NULL;
png_infop write_info_ptr = NULL;
png_infop write_end_info_ptr = NULL;
#endif
png_bytep row_buf;
png_uint_32 y;
png_uint_32 width, height;
int num_pass = 1, pass;
int bit_depth, color_type;
row_buf = NULL;
error_parameters.file_name = inname;
if ((fpin = fopen(inname, "rb")) == NULL)
{
fprintf(STDERR, "Could not find input file %s\n", inname);
return (1);
}
if ((fpout = fopen(outname, "wb")) == NULL)
{
fprintf(STDERR, "Could not open output file %s\n", outname);
FCLOSE(fpin);
return (1);
}
pngtest_debug("Allocating read and write structures");
#if defined(PNG_USER_MEM_SUPPORTED) && PNG_DEBUG
read_ptr =
png_create_read_struct_2(PNG_LIBPNG_VER_STRING, NULL,
NULL, NULL, NULL, png_debug_malloc, png_debug_free);
#else
read_ptr =
png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
#endif
png_set_error_fn(read_ptr, &error_parameters, pngtest_error,
pngtest_warning);
#ifdef PNG_WRITE_SUPPORTED
#if defined(PNG_USER_MEM_SUPPORTED) && PNG_DEBUG
write_ptr =
png_create_write_struct_2(PNG_LIBPNG_VER_STRING, NULL,
NULL, NULL, NULL, png_debug_malloc, png_debug_free);
#else
write_ptr =
png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
#endif
png_set_error_fn(write_ptr, &error_parameters, pngtest_error,
pngtest_warning);
#endif
pngtest_debug("Allocating read_info, write_info and end_info structures");
read_info_ptr = png_create_info_struct(read_ptr);
end_info_ptr = png_create_info_struct(read_ptr);
#ifdef PNG_WRITE_SUPPORTED
write_info_ptr = png_create_info_struct(write_ptr);
write_end_info_ptr = png_create_info_struct(write_ptr);
#endif
#ifdef PNG_READ_USER_CHUNKS_SUPPORTED
init_callback_info(read_info_ptr);
png_set_read_user_chunk_fn(read_ptr, &user_chunk_data,
read_user_chunk_callback);
#endif
#ifdef PNG_SETJMP_SUPPORTED
pngtest_debug("Setting jmpbuf for read struct");
if (setjmp(png_jmpbuf(read_ptr)))
{
fprintf(STDERR, "%s -> %s: libpng read error\n", inname, outname);
png_free(read_ptr, row_buf);
row_buf = NULL;
png_destroy_read_struct(&read_ptr, &read_info_ptr, &end_info_ptr);
#ifdef PNG_WRITE_SUPPORTED
png_destroy_info_struct(write_ptr, &write_end_info_ptr);
png_destroy_write_struct(&write_ptr, &write_info_ptr);
#endif
FCLOSE(fpin);
FCLOSE(fpout);
return (1);
}
#ifdef PNG_WRITE_SUPPORTED
pngtest_debug("Setting jmpbuf for write struct");
if (setjmp(png_jmpbuf(write_ptr)))
{
fprintf(STDERR, "%s -> %s: libpng write error\n", inname, outname);
png_destroy_read_struct(&read_ptr, &read_info_ptr, &end_info_ptr);
png_destroy_info_struct(write_ptr, &write_end_info_ptr);
#ifdef PNG_WRITE_SUPPORTED
png_destroy_write_struct(&write_ptr, &write_info_ptr);
#endif
FCLOSE(fpin);
FCLOSE(fpout);
return (1);
}
#endif
#endif
if (strict != 0)
{
/* Treat png_benign_error() as errors on read */
png_set_benign_errors(read_ptr, 0);
#ifdef PNG_WRITE_SUPPORTED
/* Treat them as errors on write */
png_set_benign_errors(write_ptr, 0);
#endif
/* if strict is not set, then app warnings and errors are treated as
* warnings in release builds, but not in unstable builds; this can be
* changed with '--relaxed'.
*/
}
else if (relaxed != 0)
{
/* Allow application (pngtest) errors and warnings to pass */
png_set_benign_errors(read_ptr, 1);
#ifdef PNG_WRITE_SUPPORTED
png_set_benign_errors(write_ptr, 1);
#endif
}
pngtest_debug("Initializing input and output streams");
#ifdef PNG_STDIO_SUPPORTED
png_init_io(read_ptr, fpin);
# ifdef PNG_WRITE_SUPPORTED
png_init_io(write_ptr, fpout);
# endif
#else
png_set_read_fn(read_ptr, (png_voidp)fpin, pngtest_read_data);
# ifdef PNG_WRITE_SUPPORTED
png_set_write_fn(write_ptr, (png_voidp)fpout, pngtest_write_data,
# ifdef PNG_WRITE_FLUSH_SUPPORTED
pngtest_flush);
# else
NULL);
# endif
# endif
#endif
if (status_dots_requested == 1)
{
#ifdef PNG_WRITE_SUPPORTED
png_set_write_status_fn(write_ptr, write_row_callback);
#endif
png_set_read_status_fn(read_ptr, read_row_callback);
}
else
{
#ifdef PNG_WRITE_SUPPORTED
png_set_write_status_fn(write_ptr, NULL);
#endif
png_set_read_status_fn(read_ptr, NULL);
}