pngtest.c

/* pngtest.c - a simple test program to test libpng

   libpng 1.0 beta 2 - version 0.87
   For conditions of distribution and use, see copyright notice in png.h
   Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
   January 15, 1996
*/

#include <stdio.h>
#include <stdlib.h>
#include "png.h"

#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 */

/* input and output filenames */
char inname[] = "pngtest.png";
char outname[] = "pngout.png";

png_struct read_ptr;
png_struct write_ptr;
png_info info_ptr;
png_info end_info;

char inbuf[256], outbuf[256];

int main()
{
   FILE *fpin, *fpout;
   png_bytep row_buf;
   png_byte * near_row_buf;
   png_uint_32 rowbytes;
   png_uint_32 y;
   int channels, num_pass, pass;

   row_buf = (png_bytep)0;
   near_row_buf = (png_byte *)0;

   fprintf(STDERR, "Testing libpng version %s\n", PNG_LIBPNG_VER_STRING);

   if (strcmp(png_libpng_ver, PNG_LIBPNG_VER_STRING))
   {
      fprintf(STDERR,
         "Warning: versions are different between png.h and png.c\n");
      fprintf(STDERR, "  png.h version: %s\n", PNG_LIBPNG_VER_STRING);
      fprintf(STDERR, "  png.c version: %s\n\n", png_libpng_ver);
   }

   fpin = fopen(inname, "rb");
   if (!fpin)
   {
      fprintf(STDERR, "Could not find input file %s\n", inname);
      return 1;
   }

   fpout = fopen(outname, "wb");
   if (!fpout)
   {
      fprintf(STDERR, "could not open output file %s\n", outname);
      fclose(fpin);
      return 1;
   }

   if (setjmp(read_ptr.jmpbuf))
   {
      fprintf(STDERR, "libpng read error\n");
      fclose(fpin);
      fclose(fpout);
      return 1;
   }

   if (setjmp(write_ptr.jmpbuf))
   {
      fprintf(STDERR, "libpng write error\n");
      fclose(fpin);
      fclose(fpout);
      return 1;
   }

   png_read_init(&read_ptr);
   png_write_init(&write_ptr);
   png_info_init(&info_ptr);
   png_info_init(&end_info);

   png_init_io(&read_ptr, fpin);
   png_init_io(&write_ptr, fpout);

   png_read_info(&read_ptr, &info_ptr);
   png_write_info(&write_ptr, &info_ptr);

   if ((info_ptr.color_type & 3) == 2)
      channels = 3;
   else
      channels = 1;
   if (info_ptr.color_type & 4)
      channels++;

   rowbytes = ((info_ptr.width * info_ptr.bit_depth * channels + 7) >> 3);
   near_row_buf = (png_byte *)malloc((size_t)rowbytes);
   row_buf = (png_bytep)near_row_buf;
   if (!row_buf)
   {
      fprintf(STDERR, "no memory to allocate row buffer\n");
      png_read_destroy(&read_ptr, &info_ptr, (png_infop )0);
      png_write_destroy(&write_ptr);
      fclose(fpin);
      fclose(fpout);
      return 1;
   }

   if (info_ptr.interlace_type)
   {
      num_pass = png_set_interlace_handling(&read_ptr);
      num_pass = png_set_interlace_handling(&write_ptr);
   }
   else
   {
      num_pass = 1;
   }

   for (pass = 0; pass < num_pass; pass++)
   {
      for (y = 0; y < info_ptr.height; y++)
      {
#ifdef TESTING
         fprintf(STDERR, "Processing line #%ld\n", y);
#endif
         png_read_rows(&read_ptr, (png_bytepp)&row_buf, (png_bytepp)0, 1);
         png_write_rows(&write_ptr, (png_bytepp)&row_buf, 1);
      }
   }

   png_read_end(&read_ptr, &end_info);
   png_write_end(&write_ptr, &end_info);

   png_read_destroy(&read_ptr, &info_ptr, &end_info);
   png_write_destroy(&write_ptr);

   fclose(fpin);
   fclose(fpout);

   free((void *)near_row_buf);

   fpin = fopen(inname, "rb");

   if (!fpin)
   {
      fprintf(STDERR, "could not find file %s\n", inname);
      return 1;
   }

   fpout = fopen(outname, "rb");
   if (!fpout)
   {
      fprintf(STDERR, "could not find file %s\n", outname);
      fclose(fpin);
      return 1;
   }

   while (1)
   {
      int num_in, num_out;

      num_in = fread(inbuf, 1, 256, fpin);
      num_out = fread(outbuf, 1, 256, fpout);

      if (num_in != num_out)
      {
         fprintf(STDERR, "files are of a different size\n");
         fclose(fpin);
         fclose(fpout);
         return 1;
      }

      if (!num_in)
         break;

      if (memcmp(inbuf, outbuf, num_in))
      {
         fprintf(STDERR, "files are different\n");
         fclose(fpin);
         fclose(fpout);
         return 1;
      }
   }

   fclose(fpin);
   fclose(fpout);
   fprintf(STDERR, "libpng passes test\n");

   return 0;
}