/* pngtest.c - a simple test program to test libpng * * libpng 1.2.8 - December 3, 2004 * For conditions of distribution and use, see copyright notice in png.h * 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.) * * 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 ..." */#include "png.h"#if defined(_WIN32_WCE)#  if _WIN32_WCE < 211     __error__ (f|w)printf functions are not supported on old WindowsCE.;#  endif#  include <windows.h>#  include <stdlib.h>#  define READFILE(file, data, length, check) \     if (ReadFile(file, data, length, &check,NULL)) check = 0#  define WRITEFILE(file, data, length, check)) \     if (WriteFile(file, data, length, &check, NULL)) check = 0#  define FCLOSE(file) CloseHandle(file)#else#  include <stdio.h>#  include <stdlib.h>#  include <assert.h>#  define READFILE(file, data, length, check) \     check=(png_size_t)fread(data,(png_size_t)1,length,file)#  define WRITEFILE(file, data, length, check) \     check=(png_size_t)fwrite(data,(png_size_t)1, length, file)#  define FCLOSE(file) fclose(file)#endif#if defined(PNG_NO_STDIO)#  if defined(_WIN32_WCE)     typedef HANDLE                png_FILE_p;#  else     typedef FILE                * png_FILE_p;#  endif#endif/* Makes pngtest verbose so we can find problems (needs to be before png.h) */#ifndef PNG_DEBUG#  define PNG_DEBUG 0#endif#if !PNG_DEBUG#  define SINGLE_ROWBUF_ALLOC  /* makes buffer overruns easier to nail */#endif/* Turn on CPU timing#define PNGTEST_TIMING*/#ifdef PNG_NO_FLOATING_POINT_SUPPORTED#undef PNGTEST_TIMING#endif#ifdef PNGTEST_TIMINGstatic float t_start, t_stop, t_decode, t_encode, t_misc;#include <time.h>#endif/* 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#ifdef PNGTEST_TIMINGstatic float t_start, t_stop, t_decode, t_encode, t_misc;#if !defined(PNG_tIME_SUPPORTED)#include <time.h>#endif#endif#if defined(PNG_TIME_RFC1123_SUPPORTED)static int tIME_chunk_present=0;static char tIME_string[30] = "no tIME chunk present in file";#endifstatic int verbose = 0;int test_one_file PNGARG((PNG_CONST char *inname, PNG_CONST char *outname));#ifdef __TURBOC__#include <mem.h>#endif/* defined so I can write to a file on gui/windowing platforms *//*  #define STDERR stderr  */#define STDERR stdout   /* for DOS *//* 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;void#ifdef PNG_1_0_XPNGAPI#endifread_row_callback(png_structp png_ptr, png_uint_32 row_number, int pass);void#ifdef PNG_1_0_XPNGAPI#endifread_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");}void#ifdef PNG_1_0_XPNGAPI#endifwrite_row_callback(png_structp png_ptr, png_uint_32 row_number, int pass);void#ifdef PNG_1_0_XPNGAPI#endifwrite_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");}#if defined(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];void#ifdef PNG_1_0_XPNGAPI#endifcount_filters(png_structp png_ptr, png_row_infop row_info, png_bytep data);void#ifdef PNG_1_0_XPNGAPI#endifcount_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#if defined(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;void#ifdef PNG_1_0_XPNGAPI#endifcount_zero_samples(png_structp png_ptr, png_row_infop row_info, png_bytep data);void#ifdef PNG_1_0_XPNGAPI#endifcount_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 */static int wrote_question = 0;#if defined(PNG_NO_STDIO)/* 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. */#ifndef USE_FAR_KEYWORDstatic voidpngtest_read_data(png_structp png_ptr, png_bytep data, png_size_t length){   png_size_t check;   /* 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.    */   READFILE((png_FILE_p)png_ptr->io_ptr, data, length, check);   if (check != length)   {      png_error(png_ptr, "Read Error!");   }}#else/* this is the model-independent version. Since the standard I/O library   can't handle far buffers in the medium and small models, we have to copy   the data.*/#define NEAR_BUF_SIZE 1024#define MIN(a,b) (a <= b ? a : b)static voidpngtest_read_data(png_structp png_ptr, png_bytep data, png_size_t length){   int check;   png_byte *n_data;   png_FILE_p io_ptr;   /* Check if data really is near. If so, use usual code. */   n_data = (png_byte *)CVT_PTR_NOCHECK(data);   io_ptr = (png_FILE_p)CVT_PTR(png_ptr->io_ptr);   if ((png_bytep)n_data == data)   {      READFILE(io_ptr, n_data, length, check);   }   else   {      png_byte buf[NEAR_BUF_SIZE];      png_size_t read, remaining, err;      check = 0;      remaining = length;      do      {         read = MIN(NEAR_BUF_SIZE, remaining);         READFILE(io_ptr, buf, 1, err);         png_memcpy(data, buf, read); /* copy far buffer to near buffer */         if(err != read)            break;         else            check += err;         data += read;         remaining -= read;      }      while (remaining != 0);   }   if (check != length)   {      png_error(png_ptr, "read Error");   }}#endif /* USE_FAR_KEYWORD */#if defined(PNG_WRITE_FLUSH_SUPPORTED)static voidpngtest_flush(png_structp png_ptr){#if !defined(_WIN32_WCE)   png_FILE_p io_ptr;   io_ptr = (png_FILE_p)CVT_PTR((png_ptr->io_ptr));   if (io_ptr != NULL)      fflush(io_ptr);#endif}#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. */#ifndef USE_FAR_KEYWORDstatic voidpngtest_write_data(png_structp png_ptr, png_bytep data, png_size_t length){   png_uint_32 check;   WRITEFILE((png_FILE_p)png_ptr->io_ptr,  data, length, check);   if (check != length)   {      png_error(png_ptr, "Write Error");