pngget.c

/* pngget.c - retrieval of values from info struct

   libpng 1.0 beta 6 - version 0.96
   For conditions of distribution and use, see copyright notice in png.h
   Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
   Copyright (c) 1996, 1997 Andreas Dilger
   May 12, 1997
   */

#define PNG_INTERNAL
#include "png.h"

png_uint_32
png_get_valid(png_structp png_ptr, png_infop info_ptr, png_uint_32 flag)
{
   if (info_ptr != NULL)
      return(info_ptr->valid & flag);
   else
      return(0);
}

png_uint_32
png_get_rowbytes(png_structp png_ptr, png_infop info_ptr)
{
   if (info_ptr != NULL)
      return(info_ptr->rowbytes);
   else
      return(0);
}

png_byte
png_get_channels(png_structp png_ptr, png_infop info_ptr)
{
   if (info_ptr != NULL)
      return(info_ptr->channels);
   else
      return(0);
}

png_bytep
png_get_signature(png_structp png_ptr, png_infop info_ptr)
{
   if (info_ptr != NULL)
      return(info_ptr->signature);
   else
      return(NULL);
}

#if defined(PNG_READ_bKGD_SUPPORTED)
png_uint_32
png_get_bKGD(png_structp png_ptr, png_infop info_ptr,
   png_color_16p *background)
{
   if (info_ptr != NULL && info_ptr->valid & PNG_INFO_bKGD &&
      background != NULL)
   {
      png_debug1(1, "in %s retrieval function\n", "bKGD");
      *background = &(info_ptr->background);
      return (PNG_INFO_bKGD);
   }
   return (0);
}
#endif

#if defined(PNG_READ_cHRM_SUPPORTED)
png_uint_32
png_get_cHRM(png_structp png_ptr, png_infop info_ptr,
   double *white_x, double *white_y, double *red_x, double *red_y,
   double *green_x, double *green_y, double *blue_x, double *blue_y)
{
   if (info_ptr != NULL && info_ptr->valid & PNG_INFO_cHRM)
   {
      png_debug1(1, "in %s retrieval function\n", "cHRM");
      if (white_x != NULL)
         *white_x = (double)info_ptr->x_white;
      if (white_y != NULL)
         *white_y = (double)info_ptr->y_white;
      if (red_x != NULL)
         *red_x = (double)info_ptr->x_red;
      if (red_y != NULL)
         *red_y = (double)info_ptr->y_red;
      if (green_x != NULL)
         *green_x = (double)info_ptr->x_green;
      if (green_y != NULL)
         *green_y = (double)info_ptr->y_green;
      if (blue_x != NULL)
         *blue_x = (double)info_ptr->x_blue;
      if (blue_y != NULL)
         *blue_y = (double)info_ptr->y_blue;
      return (PNG_INFO_cHRM);
   }
   return (0);
}
#endif

#if defined(PNG_READ_gAMA_SUPPORTED)
png_uint_32
png_get_gAMA(png_structp png_ptr, png_infop info_ptr, double *file_gamma)
{
   if (info_ptr != NULL && info_ptr->valid & PNG_INFO_gAMA &&
      file_gamma != NULL)
   {
      png_debug1(1, "in %s retrieval function\n", "gAMA");
      *file_gamma = (double)info_ptr->gamma;
      return (PNG_INFO_gAMA);
   }
   return (0);
}
#endif

#if defined(PNG_READ_hIST_SUPPORTED)
png_uint_32
png_get_hIST(png_structp png_ptr, png_infop info_ptr, png_uint_16p *hist)
{
   if (info_ptr != NULL && info_ptr->valid & PNG_INFO_hIST && hist != NULL)
   {
      png_debug1(1, "in %s retrieval function\n", "hIST");
      *hist = info_ptr->hist;
      return (PNG_INFO_hIST);
   }
   return (0);
}
#endif

png_uint_32
png_get_IHDR(png_structp png_ptr, png_infop info_ptr,
   png_uint_32 *width, png_uint_32 *height, int *bit_depth,
   int *color_type, int *interlace_type, int *compression_type,
   int *filter_type)
   
{
   if (info_ptr != NULL && width != NULL && height != NULL &&
      bit_depth != NULL && color_type != NULL)
   {
      png_debug1(1, "in %s retrieval function\n", "IHDR");
      *width = info_ptr->width;
      *height = info_ptr->height;
      *bit_depth = info_ptr->bit_depth;
      *color_type = info_ptr->color_type;
      if (compression_type != NULL)
         *compression_type = info_ptr->compression_type;
      if (filter_type != NULL)
         *filter_type = info_ptr->filter_type;
      if (interlace_type != NULL)
         *interlace_type = info_ptr->interlace_type;
      return (1);
   }
   return (0);
}

#if defined(PNG_READ_oFFs_SUPPORTED)
png_uint_32
png_get_oFFs(png_structp png_ptr, png_infop info_ptr,
   png_uint_32 *offset_x, png_uint_32 *offset_y, int *unit_type)
{
   if (info_ptr != NULL && info_ptr->valid & PNG_INFO_oFFs &&
      offset_x != NULL && offset_y != NULL && unit_type != NULL)
   {
      png_debug1(1, "in %s retrieval function\n", "oFFs");
      *offset_x = info_ptr->x_offset;
      *offset_y = info_ptr->y_offset;
      *unit_type = (int)info_ptr->offset_unit_type;
      return (PNG_INFO_oFFs);
   }
   return (0);
}
#endif

#if defined(PNG_READ_pCAL_SUPPORTED)
png_uint_32
png_get_pCAL(png_structp png_ptr, png_infop info_ptr,
   png_charp *purpose, png_int_32 *X0, png_int_32 *X1, int *type, int *nparams,
   png_charp *units, png_charpp *params)
{
   if (info_ptr != NULL && info_ptr->valid & PNG_INFO_pCAL &&
      purpose != NULL && X0 != NULL && X1 != NULL && type != NULL &&
      nparams != NULL && units != NULL && params != NULL)
   {
      png_debug1(1, "in %s retrieval function\n", "pCAL");
      *purpose = info_ptr->pcal_purpose;
      *X0 = info_ptr->pcal_X0;
      *X1 = info_ptr->pcal_X1;
      *type = (int)info_ptr->pcal_type;
      *nparams = (int)info_ptr->pcal_nparams;
      *units = info_ptr->pcal_units;
      *params = info_ptr->pcal_params;
      return (PNG_INFO_pCAL);
   }
   return (0);
}
#endif

#if defined(PNG_READ_pHYs_SUPPORTED)
png_uint_32
png_get_pHYs(png_structp png_ptr, png_infop info_ptr,
   png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type)
{
   if (info_ptr != NULL && info_ptr->valid & PNG_INFO_pHYs &&
      res_x != NULL && res_y != NULL && unit_type != NULL)
   {
      png_debug1(1, "in %s retrieval function\n", "pHYs");
      *res_x = info_ptr->x_pixels_per_unit;
      *res_y = info_ptr->y_pixels_per_unit;
      *unit_type = (int)info_ptr->phys_unit_type;
      return (PNG_INFO_pHYs);
   }
   return (0);
}
#endif

png_uint_32
png_get_PLTE(png_structp png_ptr, png_infop info_ptr, png_colorp *palette,
   int *num_palette)
{
   if (info_ptr != NULL && info_ptr->valid & PNG_INFO_PLTE && palette != NULL)
   {
      png_debug1(1, "in %s retrieval function\n", "PLTE");
      *palette = info_ptr->palette;
      *num_palette = info_ptr->num_palette;
      png_debug1(3, "num_palette = %d\n", *num_palette);
      return (PNG_INFO_PLTE);
   }
   return (0);
}

#if defined(PNG_READ_sBIT_SUPPORTED)
png_uint_32
png_get_sBIT(png_structp png_ptr, png_infop info_ptr, png_color_8p *sig_bit)
{
   if (info_ptr != NULL && info_ptr->valid & PNG_INFO_sBIT && sig_bit != NULL)
   {
      png_debug1(1, "in %s retrieval function\n", "sBIT");
      *sig_bit = &(info_ptr->sig_bit);
      return (PNG_INFO_sBIT);
   }
   return (0);
}
#endif

#if defined(PNG_READ_tEXt_SUPPORTED) || defined(PNG_READ_zTXt_SUPPORTED)
png_uint_32
png_get_text(png_structp png_ptr, png_infop info_ptr, png_textp *text_ptr,
   int *num_text)
{
   if ((info_ptr != NULL) || (info_ptr->num_text > 0))
   {
      png_debug1(1, "in %s retrieval function\n",
         (png_ptr->chunk_name[0] == '\0' ? "text" : png_ptr->chunk_name));
      if (text_ptr != NULL)
         *text_ptr = info_ptr->text;
      if (num_text != NULL)
         *num_text = info_ptr->num_text;
      return (info_ptr->num_text);
   }
   return(0);
}
#endif

#if defined(PNG_READ_tIME_SUPPORTED)
png_uint_32
png_get_tIME(png_structp png_ptr, png_infop info_ptr, png_timep *mod_time)
{
   if (info_ptr != NULL && info_ptr->valid & PNG_INFO_tIME && mod_time != NULL)
   {
      png_debug1(1, "in %s retrieval function\n", "tIME");
      *mod_time = &(info_ptr->mod_time);
      return (PNG_INFO_tIME);
   }
   return (0);
}
#endif

#if defined(PNG_READ_tRNS_SUPPORTED)
png_uint_32
png_get_tRNS(png_structp png_ptr, png_infop info_ptr,
   png_bytep *trans, int *num_trans, png_color_16p *trans_values)
{
   if (info_ptr != NULL && info_ptr->valid & PNG_INFO_tRNS)
   {
      png_debug1(1, "in %s retrieval function\n", "tRNS");
      if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE && trans != NULL)
      {
          *trans = info_ptr->trans;
      }
      else if (trans_values != NULL)
      {
         *trans_values = &(info_ptr->trans_values);
      }
      else
      {
         return (0);
      }
      *num_trans = info_ptr->num_trans;
      return (PNG_INFO_tRNS);
   }
   return (0);
}
#endif