/* pngwrite.c - general routines to write a PNG file

 *

 * Last changed in libpng 1.2.31 [August 19, 2008]

 * For conditions of distribution and use, see copyright notice in png.h

 * Copyright (c) 1998-2008 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.)

 */

/* get internal access to png.h */

#define PNG_INTERNAL

#include "png.h"

#ifdef PNG_WRITE_SUPPORTED

/* Writes all the PNG information.  This is the suggested way to use the

 * library.  If you have a new chunk to add, make a function to write it,

 * and put it in the correct location here.  If you want the chunk written

 * after the image data, put it in png_write_end().  I strongly encourage

 * you to supply a PNG_INFO_ flag, and check info_ptr->valid before writing

 * the chunk, as that will keep the code from breaking if you want to just

 * write a plain PNG file.  If you have long comments, I suggest writing

 * them in png_write_end(), and compressing them.

 */

void PNGAPI

png_write_info_before_PLTE(png_structp png_ptr, png_infop info_ptr)

{

   png_debug(1, "in png_write_info_before_PLTE\n");

   if (png_ptr == NULL || info_ptr == NULL)

      return;

   if (!(png_ptr->mode & PNG_WROTE_INFO_BEFORE_PLTE))

   {

   png_write_sig(png_ptr); /* write PNG signature */

#if defined(PNG_MNG_FEATURES_SUPPORTED)

   if ((png_ptr->mode&PNG_HAVE_PNG_SIGNATURE)&&(png_ptr->mng_features_permitted))

   {

      png_warning(png_ptr, "MNG features are not allowed in a PNG datastream");

      png_ptr->mng_features_permitted=0;

   }

#endif

   /* write IHDR information. */

   png_write_IHDR(png_ptr, info_ptr->width, info_ptr->height,

      info_ptr->bit_depth, info_ptr->color_type, info_ptr->compression_type,

      info_ptr->filter_type,

#if defined(PNG_WRITE_INTERLACING_SUPPORTED)

      info_ptr->interlace_type);

#else

      0);

#endif

   /* the rest of these check to see if the valid field has the appropriate

      flag set, and if it does, writes the chunk. */

#if defined(PNG_WRITE_gAMA_SUPPORTED)

   if (info_ptr->valid & PNG_INFO_gAMA)

   {

#  ifdef PNG_FLOATING_POINT_SUPPORTED

      png_write_gAMA(png_ptr, info_ptr->gamma);

#else

#ifdef PNG_FIXED_POINT_SUPPORTED

      png_write_gAMA_fixed(png_ptr, info_ptr->int_gamma);

#  endif

#endif

   }

#endif

#if defined(PNG_WRITE_sRGB_SUPPORTED)

   if (info_ptr->valid & PNG_INFO_sRGB)

      png_write_sRGB(png_ptr, (int)info_ptr->srgb_intent);

#endif

#if defined(PNG_WRITE_iCCP_SUPPORTED)

   if (info_ptr->valid & PNG_INFO_iCCP)

      png_write_iCCP(png_ptr, info_ptr->iccp_name, PNG_COMPRESSION_TYPE_BASE,

                     info_ptr->iccp_profile, (int)info_ptr->iccp_proflen);

#endif

#if defined(PNG_WRITE_sBIT_SUPPORTED)

   if (info_ptr->valid & PNG_INFO_sBIT)

      png_write_sBIT(png_ptr, &(info_ptr->sig_bit), info_ptr->color_type);

#endif

#if defined(PNG_WRITE_cHRM_SUPPORTED)

   if (info_ptr->valid & PNG_INFO_cHRM)

   {

#ifdef PNG_FLOATING_POINT_SUPPORTED

      png_write_cHRM(png_ptr,

         info_ptr->x_white, info_ptr->y_white,

         info_ptr->x_red, info_ptr->y_red,

         info_ptr->x_green, info_ptr->y_green,

         info_ptr->x_blue, info_ptr->y_blue);

#else

#  ifdef PNG_FIXED_POINT_SUPPORTED

      png_write_cHRM_fixed(png_ptr,

         info_ptr->int_x_white, info_ptr->int_y_white,

         info_ptr->int_x_red, info_ptr->int_y_red,

         info_ptr->int_x_green, info_ptr->int_y_green,

         info_ptr->int_x_blue, info_ptr->int_y_blue);

#  endif

#endif

   }

#endif

#if defined(PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED)

   if (info_ptr->unknown_chunks_num)

   {

       png_unknown_chunk *up;

       png_debug(5, "writing extra chunks\n");

       for (up = info_ptr->unknown_chunks;

            up < info_ptr->unknown_chunks + info_ptr->unknown_chunks_num;

            up++)

       {

         int keep=png_handle_as_unknown(png_ptr, up->name);

         if (keep != PNG_HANDLE_CHUNK_NEVER &&

            up->location && !(up->location & PNG_HAVE_PLTE) &&

            !(up->location & PNG_HAVE_IDAT) &&

            ((up->name[3] & 0x20) || keep == PNG_HANDLE_CHUNK_ALWAYS ||

            (png_ptr->flags & PNG_FLAG_KEEP_UNSAFE_CHUNKS)))

         {

            if (up->size == 0)

               png_warning(png_ptr, "Writing zero-length unknown chunk");

            png_write_chunk(png_ptr, up->name, up->data, up->size);

         }

       }

   }

#endif

      png_ptr->mode |= PNG_WROTE_INFO_BEFORE_PLTE;

   }

}

void PNGAPI

png_write_info(png_structp png_ptr, png_infop info_ptr)

{

#if defined(PNG_WRITE_TEXT_SUPPORTED) || defined(PNG_WRITE_sPLT_SUPPORTED)

   int i;

#endif

   png_debug(1, "in png_write_info\n");

   if (png_ptr == NULL || info_ptr == NULL)

      return;

   png_write_info_before_PLTE(png_ptr, info_ptr);

   if (info_ptr->valid & PNG_INFO_PLTE)

      png_write_PLTE(png_ptr, info_ptr->palette,

         (png_uint_32)info_ptr->num_palette);

   else if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)

      png_error(png_ptr, "Valid palette required for paletted images");

#if defined(PNG_WRITE_tRNS_SUPPORTED)

   if (info_ptr->valid & PNG_INFO_tRNS)

      {

#if defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)

         /* invert the alpha channel (in tRNS) */

         if ((png_ptr->transformations & PNG_INVERT_ALPHA) &&

            info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)

         {

            int j;

            for (j=0; j<(int)info_ptr->num_trans; j++)

               info_ptr->trans[j] = (png_byte)(255 - info_ptr->trans[j]);

         }

#endif

      png_write_tRNS(png_ptr, info_ptr->trans, &(info_ptr->trans_values),

         info_ptr->num_trans, info_ptr->color_type);

      }

#endif

#if defined(PNG_WRITE_bKGD_SUPPORTED)

   if (info_ptr->valid & PNG_INFO_bKGD)

      png_write_bKGD(png_ptr, &(info_ptr->background), info_ptr->color_type);

#endif

#if defined(PNG_WRITE_hIST_SUPPORTED)

   if (info_ptr->valid & PNG_INFO_hIST)

      png_write_hIST(png_ptr, info_ptr->hist, info_ptr->num_palette);

#endif

#if defined(PNG_WRITE_oFFs_SUPPORTED)

   if (info_ptr->valid & PNG_INFO_oFFs)

      png_write_oFFs(png_ptr, info_ptr->x_offset, info_ptr->y_offset,

         info_ptr->offset_unit_type);

#endif

#if defined(PNG_WRITE_pCAL_SUPPORTED)

   if (info_ptr->valid & PNG_INFO_pCAL)

      png_write_pCAL(png_ptr, info_ptr->pcal_purpose, info_ptr->pcal_X0,

         info_ptr->pcal_X1, info_ptr->pcal_type, info_ptr->pcal_nparams,

         info_ptr->pcal_units, info_ptr->pcal_params);

#endif

#if defined(PNG_WRITE_sCAL_SUPPORTED)

   if (info_ptr->valid & PNG_INFO_sCAL)

#if defined(PNG_FLOATING_POINT_SUPPORTED) && !defined(PNG_NO_STDIO)

      png_write_sCAL(png_ptr, (int)info_ptr->scal_unit,

          info_ptr->scal_pixel_width, info_ptr->scal_pixel_height);

#else

#ifdef PNG_FIXED_POINT_SUPPORTED

      png_write_sCAL_s(png_ptr, (int)info_ptr->scal_unit,

          info_ptr->scal_s_width, info_ptr->scal_s_height);

#else

      png_warning(png_ptr,

          "png_write_sCAL not supported; sCAL chunk not written.");

#endif

#endif

#endif

#if defined(PNG_WRITE_pHYs_SUPPORTED)

   if (info_ptr->valid & PNG_INFO_pHYs)

      png_write_pHYs(png_ptr, info_ptr->x_pixels_per_unit,

         info_ptr->y_pixels_per_unit, info_ptr->phys_unit_type);

#endif

#if defined(PNG_WRITE_tIME_SUPPORTED)

   if (info_ptr->valid & PNG_INFO_tIME)

   {

      png_write_tIME(png_ptr, &(info_ptr->mod_time));

      png_ptr->mode |= PNG_WROTE_tIME;

   }

#endif

#if defined(PNG_WRITE_sPLT_SUPPORTED)

   if (info_ptr->valid & PNG_INFO_sPLT)

     for (i = 0; i < (int)info_ptr->splt_palettes_num; i++)

       png_write_sPLT(png_ptr, info_ptr->splt_palettes + i);

#endif

#if defined(PNG_WRITE_TEXT_SUPPORTED)

   /* Check to see if we need to write text chunks */

   for (i = 0; i < info_ptr->num_text; i++)

   {

      png_debug2(2, "Writing header text chunk %d, type %d\n", i,

         info_ptr->text[i].compression);

      /* an internationalized chunk? */

      if (info_ptr->text[i].compression > 0)

      {

#if defined(PNG_WRITE_iTXt_SUPPORTED)

          /* write international chunk */

          png_write_iTXt(png_ptr,

                         info_ptr->text[i].compression,

                         info_ptr->text[i].key,

                         info_ptr->text[i].lang,

                         info_ptr->text[i].lang_key,

                         info_ptr->text[i].text);

#else

          png_warning(png_ptr, "Unable to write international text");

#endif

          /* Mark this chunk as written */

          info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;

      }

      /* If we want a compressed text chunk */

      else if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_zTXt)

      {

#if defined(PNG_WRITE_zTXt_SUPPORTED)

         /* write compressed chunk */

         png_write_zTXt(png_ptr, info_ptr->text[i].key,

            info_ptr->text[i].text, 0,

            info_ptr->text[i].compression);

#else

         png_warning(png_ptr, "Unable to write compressed text");

#endif

         /* Mark this chunk as written */

         info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_zTXt_WR;

      }

      else if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_NONE)

      {

#if defined(PNG_WRITE_tEXt_SUPPORTED)

         /* write uncompressed chunk */

         png_write_tEXt(png_ptr, info_ptr->text[i].key,

                         info_ptr->text[i].text,

                         0);

#else

         png_warning(png_ptr, "Unable to write uncompressed text");

#endif

         /* Mark this chunk as written */

         info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;

      }

   }

#endif

#if defined(PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED)

   if (info_ptr->unknown_chunks_num)

   {

       png_unknown_chunk *up;

       png_debug(5, "writing extra chunks\n");

       for (up = info_ptr->unknown_chunks;

            up < info_ptr->unknown_chunks + info_ptr->unknown_chunks_num;

            up++)

       {

         int keep=png_handle_as_unknown(png_ptr, up->name);

         if (keep != PNG_HANDLE_CHUNK_NEVER &&

            up->location && (up->location & PNG_HAVE_PLTE) &&

            !(up->location & PNG_HAVE_IDAT) &&

            ((up->name[3] & 0x20) || keep == PNG_HANDLE_CHUNK_ALWAYS ||

            (png_ptr->flags & PNG_FLAG_KEEP_UNSAFE_CHUNKS)))

         {

            png_write_chunk(png_ptr, up->name, up->data, up->size);

         }

       }

   }

#endif

}

/* Writes the end of the PNG file.  If you don't want to write comments or

 * time information, you can pass NULL for info.  If you already wrote these

 * in png_write_info(), do not write them again here.  If you have long

 * comments, I suggest writing them here, and compressing them.

 */

void PNGAPI

png_write_end(png_structp png_ptr, png_infop info_ptr)

{

   png_debug(1, "in png_write_end\n");

   if (png_ptr == NULL)

      return;

   if (!(png_ptr->mode & PNG_HAVE_IDAT))

      png_error(png_ptr, "No IDATs written into file");

   /* see if user wants us to write information chunks */

   if (info_ptr != NULL)

   {

#if defined(PNG_WRITE_TEXT_SUPPORTED)

      int i; /* local index variable */

#endif

#if defined(PNG_WRITE_tIME_SUPPORTED)

      /* check to see if user has supplied a time chunk */

      if ((info_ptr->valid & PNG_INFO_tIME) &&

         !(png_ptr->mode & PNG_WROTE_tIME))

         png_write_tIME(png_ptr, &(info_ptr->mod_time));

#endif

#if defined(PNG_WRITE_TEXT_SUPPORTED)

      /* loop through comment chunks */

      for (i = 0; i < info_ptr->num_text; i++)

      {

         png_debug2(2, "Writing trailer text chunk %d, type %d\n", i,

            info_ptr->text[i].compression);

         /* an internationalized chunk? */

         if (info_ptr->text[i].compression > 0)

         {

#if defined(PNG_WRITE_iTXt_SUPPORTED)

             /* write international chunk */

             png_write_iTXt(png_ptr,

                         info_ptr->text[i].compression,

                         info_ptr->text[i].key,

                         info_ptr->text[i].lang,

                         info_ptr->text[i].lang_key,

                         info_ptr->text[i].text);

#else

             png_warning(png_ptr, "Unable to write international text");

#endif

             /* Mark this chunk as written */

             info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;

         }

         else if (info_ptr->text[i].compression >= PNG_TEXT_COMPRESSION_zTXt)

         {

#if defined(PNG_WRITE_zTXt_SUPPORTED)

            /* write compressed chunk */

            png_write_zTXt(png_ptr, info_ptr->text[i].key,

               info_ptr->text[i].text, 0,

               info_ptr->text[i].compression);

#else

            png_warning(png_ptr, "Unable to write compressed text");

#endif

            /* Mark this chunk as written */

            info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_zTXt_WR;

         }

         else if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_NONE)

         {

#if defined(PNG_WRITE_tEXt_SUPPORTED)

            /* write uncompressed chunk */

            png_write_tEXt(png_ptr, info_ptr->text[i].key,

               info_ptr->text[i].text, 0);

#else

            png_warning(png_ptr, "Unable to write uncompressed text");

#endif

            /* Mark this chunk as written */

            info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;

         }

      }

#endif

#if defined(PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED)

   if (info_ptr->unknown_chunks_num)

   {

       png_unknown_chunk *up;

       png_debug(5, "writing extra chunks\n");

       for (up = info_ptr->unknown_chunks;

            up < info_ptr->unknown_chunks + info_ptr->unknown_chunks_num;

            up++)

       {

         int keep=png_handle_as_unknown(png_ptr, up->name);

         if (keep != PNG_HANDLE_CHUNK_NEVER &&

            up->location && (up->location & PNG_AFTER_IDAT) &&

            ((up->name[3] & 0x20) || keep == PNG_HANDLE_CHUNK_ALWAYS ||

            (png_ptr->flags & PNG_FLAG_KEEP_UNSAFE_CHUNKS)))

         {

            png_write_chunk(png_ptr, up->name, up->data, up->size);

         }

       }

   }

#endif

   }

   png_ptr->mode |= PNG_AFTER_IDAT;

   /* write end of PNG file */

   png_write_IEND(png_ptr);

   /* This flush, added in libpng-1.0.8, removed from libpng-1.0.9beta03,

    * and restored again in libpng-1.2.30, may cause some applications that

    * do not set png_ptr->output_flush_fn to crash.  If your application

    * experiences a problem, please try building libpng with

    * PNG_WRITE_FLUSH_AFTER_IEND_SUPPORTED defined, and report the event to

    * png-mng-implement at lists.sf.net .  This kludge will be removed

    * from libpng-1.4.0.

    */

#if defined(PNG_WRITE_FLUSH_SUPPORTED) && \

    defined(PNG_WRITE_FLUSH_AFTER_IEND_SUPPORTED)

   png_flush(png_ptr);

#endif

}

#if defined(PNG_WRITE_tIME_SUPPORTED)

#if !defined(_WIN32_WCE)

/* "time.h" functions are not supported on WindowsCE */

void PNGAPI

png_convert_from_struct_tm(png_timep ptime, struct tm FAR * ttime)

{

   png_debug(1, "in png_convert_from_struct_tm\n");

   ptime->year = (png_uint_16)(1900 + ttime->tm_year);

   ptime->month = (png_byte)(ttime->tm_mon + 1);

   ptime->day = (png_byte)ttime->tm_mday;

   ptime->hour = (png_byte)ttime->tm_hour;

   ptime->minute = (png_byte)ttime->tm_min;

   ptime->second = (png_byte)ttime->tm_sec;

}

void PNGAPI

png_convert_from_time_t(png_timep ptime, time_t ttime)

{

   struct tm *tbuf;

   png_debug(1, "in png_convert_from_time_t\n");

   tbuf = gmtime(&ttime);

   png_convert_from_struct_tm(ptime, tbuf);

}

#endif

#endif

/* Initialize png_ptr structure, and allocate any memory needed */

png_structp PNGAPI

png_create_write_struct(png_const_charp user_png_ver, png_voidp error_ptr,

   png_error_ptr error_fn, png_error_ptr warn_fn)

{

#ifdef PNG_USER_MEM_SUPPORTED

   return (png_create_write_struct_2(user_png_ver, error_ptr, error_fn,

      warn_fn, png_voidp_NULL, png_malloc_ptr_NULL, png_free_ptr_NULL));

}

/* Alternate initialize png_ptr structure, and allocate any memory needed */

png_structp PNGAPI

png_create_write_struct_2(png_const_charp user_png_ver, png_voidp error_ptr,

   png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr,

   png_malloc_ptr malloc_fn, png_free_ptr free_fn)

{

#endif /* PNG_USER_MEM_SUPPORTED */

#ifdef PNG_SETJMP_SUPPORTED

    volatile

#endif

    png_structp png_ptr;

#ifdef PNG_SETJMP_SUPPORTED

#ifdef USE_FAR_KEYWORD

   jmp_buf jmpbuf;

#endif

#endif

   int i;

   png_debug(1, "in png_create_write_struct\n");

#ifdef PNG_USER_MEM_SUPPORTED

   png_ptr = (png_structp)png_create_struct_2(PNG_STRUCT_PNG,

      (png_malloc_ptr)malloc_fn, (png_voidp)mem_ptr);

#else

   png_ptr = (png_structp)png_create_struct(PNG_STRUCT_PNG);

#endif /* PNG_USER_MEM_SUPPORTED */

   if (png_ptr == NULL)

      return (NULL);

   /* added at libpng-1.2.6 */

#ifdef PNG_SET_USER_LIMITS_SUPPORTED

   png_ptr->user_width_max=PNG_USER_WIDTH_MAX;

   png_ptr->user_height_max=PNG_USER_HEIGHT_MAX;

#endif

#ifdef PNG_SETJMP_SUPPORTED

#ifdef USE_FAR_KEYWORD

   if (setjmp(jmpbuf))

#else

   if (setjmp(png_ptr->jmpbuf))

#endif

   {

      png_free(png_ptr, png_ptr->zbuf);

       png_ptr->zbuf=NULL;

      png_destroy_struct(png_ptr);

      return (NULL);

   }

#ifdef USE_FAR_KEYWORD

   png_memcpy(png_ptr->jmpbuf, jmpbuf, png_sizeof(jmp_buf));

#endif

#endif

#ifdef PNG_USER_MEM_SUPPORTED

   png_set_mem_fn(png_ptr, mem_ptr, malloc_fn, free_fn);

#endif /* PNG_USER_MEM_SUPPORTED */

   png_set_error_fn(png_ptr, error_ptr, error_fn, warn_fn);

   if (user_png_ver)

   {

     i=0;

     do

     {

       if (user_png_ver[i] != png_libpng_ver[i])

          png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH;

     } while (png_libpng_ver[i++]);

   }

   if (png_ptr->flags & PNG_FLAG_LIBRARY_MISMATCH)

   {

     /* Libpng 0.90 and later are binary incompatible with libpng 0.89, so

      * we must recompile any applications that use any older library version.

      * For versions after libpng 1.0, we will be compatible, so we need

      * only check the first digit.

      */

     if (user_png_ver == NULL || user_png_ver[0] != png_libpng_ver[0] ||

         (user_png_ver[0] == '1' && user_png_ver[2] != png_libpng_ver[2]) ||

         (user_png_ver[0] == '0' && user_png_ver[2] < '9'))

     {

#if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE)

        char msg[80];

        if (user_png_ver)

        {

          png_snprintf(msg, 80,

             "Application was compiled with png.h from libpng-%.20s",