X-Git-Url: https://git.saurik.com/wxWidgets.git/blobdiff_plain/4946a942d77cf51e00aa56404756e124d7c11411..64ea838d8f4d1853b7d850db93ee565e901d099a:/src/png/pngget.c?ds=sidebyside

diff --git a/src/png/pngget.c b/src/png/pngget.c
index d3805a6e06..43400cda7e 100644
--- a/src/png/pngget.c
+++ b/src/png/pngget.c
@@ -1,618 +1,808 @@
 
 /* pngget.c - retrieval of values from info struct
  *
- * libpng 1.2.4 - July 8, 2002
- * For conditions of distribution and use, see copyright notice in png.h
- * Copyright (c) 1998-2002 Glenn Randers-Pehrson
+ * Last changed in libpng 1.5.7 [December 15, 2011]
+ * Copyright (c) 1998-2011 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
+ *
  */
 
-#define PNG_INTERNAL
-#include "png.h"
+#include "pngpriv.h"
+
+#if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
 
 png_uint_32 PNGAPI
-png_get_valid(png_structp png_ptr, png_infop info_ptr, png_uint_32 flag)
+png_get_valid(png_const_structp png_ptr, png_const_infop info_ptr,
+    png_uint_32 flag)
 {
    if (png_ptr != NULL && info_ptr != NULL)
       return(info_ptr->valid & flag);
-   else
-      return(0);
+
+   return(0);
 }
 
-png_uint_32 PNGAPI
-png_get_rowbytes(png_structp png_ptr, png_infop info_ptr)
+png_size_t PNGAPI
+png_get_rowbytes(png_const_structp png_ptr, png_const_infop info_ptr)
 {
    if (png_ptr != NULL && info_ptr != NULL)
       return(info_ptr->rowbytes);
-   else
-      return(0);
+
+   return(0);
 }
 
-#if defined(PNG_INFO_IMAGE_SUPPORTED)
+#ifdef PNG_INFO_IMAGE_SUPPORTED
 png_bytepp PNGAPI
-png_get_rows(png_structp png_ptr, png_infop info_ptr)
+png_get_rows(png_const_structp png_ptr, png_const_infop info_ptr)
 {
    if (png_ptr != NULL && info_ptr != NULL)
       return(info_ptr->row_pointers);
-   else
-      return(0);
+
+   return(0);
 }
 #endif
 
 #ifdef PNG_EASY_ACCESS_SUPPORTED
-/* easy access to info, added in libpng-0.99 */
+/* Easy access to info, added in libpng-0.99 */
 png_uint_32 PNGAPI
-png_get_image_width(png_structp png_ptr, png_infop info_ptr)
+png_get_image_width(png_const_structp png_ptr, png_const_infop info_ptr)
 {
    if (png_ptr != NULL && info_ptr != NULL)
-   {
       return info_ptr->width;
-   }
+
    return (0);
 }
 
 png_uint_32 PNGAPI
-png_get_image_height(png_structp png_ptr, png_infop info_ptr)
+png_get_image_height(png_const_structp png_ptr, png_const_infop info_ptr)
 {
    if (png_ptr != NULL && info_ptr != NULL)
-   {
       return info_ptr->height;
-   }
+
    return (0);
 }
 
 png_byte PNGAPI
-png_get_bit_depth(png_structp png_ptr, png_infop info_ptr)
+png_get_bit_depth(png_const_structp png_ptr, png_const_infop info_ptr)
 {
    if (png_ptr != NULL && info_ptr != NULL)
-   {
       return info_ptr->bit_depth;
-   }
+
    return (0);
 }
 
 png_byte PNGAPI
-png_get_color_type(png_structp png_ptr, png_infop info_ptr)
+png_get_color_type(png_const_structp png_ptr, png_const_infop info_ptr)
 {
    if (png_ptr != NULL && info_ptr != NULL)
-   {
       return info_ptr->color_type;
-   }
+
    return (0);
 }
 
 png_byte PNGAPI
-png_get_filter_type(png_structp png_ptr, png_infop info_ptr)
+png_get_filter_type(png_const_structp png_ptr, png_const_infop info_ptr)
 {
    if (png_ptr != NULL && info_ptr != NULL)
-   {
       return info_ptr->filter_type;
-   }
+
    return (0);
 }
 
 png_byte PNGAPI
-png_get_interlace_type(png_structp png_ptr, png_infop info_ptr)
+png_get_interlace_type(png_const_structp png_ptr, png_const_infop info_ptr)
 {
    if (png_ptr != NULL && info_ptr != NULL)
-   {
       return info_ptr->interlace_type;
-   }
+
    return (0);
 }
 
 png_byte PNGAPI
-png_get_compression_type(png_structp png_ptr, png_infop info_ptr)
+png_get_compression_type(png_const_structp png_ptr, png_const_infop info_ptr)
 {
    if (png_ptr != NULL && info_ptr != NULL)
-   {
       return info_ptr->compression_type;
-   }
+
    return (0);
 }
 
 png_uint_32 PNGAPI
-png_get_x_pixels_per_meter(png_structp png_ptr, png_infop info_ptr)
+png_get_x_pixels_per_meter(png_const_structp png_ptr, png_const_infop info_ptr)
 {
-   if (png_ptr != NULL && info_ptr != NULL)
-#if defined(PNG_pHYs_SUPPORTED)
-   if (info_ptr->valid & PNG_INFO_pHYs)
-   {
-      png_debug1(1, "in %s retrieval function\n", "png_get_x_pixels_per_meter");
-      if(info_ptr->phys_unit_type != PNG_RESOLUTION_METER)
-          return (0);
-      else return (info_ptr->x_pixels_per_unit);
-   }
-#else
-   return (0);
+#ifdef PNG_pHYs_SUPPORTED
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs))
+      {
+         png_debug1(1, "in %s retrieval function",
+             "png_get_x_pixels_per_meter");
+
+         if (info_ptr->phys_unit_type == PNG_RESOLUTION_METER)
+            return (info_ptr->x_pixels_per_unit);
+      }
 #endif
+
    return (0);
 }
 
 png_uint_32 PNGAPI
-png_get_y_pixels_per_meter(png_structp png_ptr, png_infop info_ptr)
+png_get_y_pixels_per_meter(png_const_structp png_ptr, png_const_infop info_ptr)
 {
-   if (png_ptr != NULL && info_ptr != NULL)
-#if defined(PNG_pHYs_SUPPORTED)
-   if (info_ptr->valid & PNG_INFO_pHYs)
+#ifdef PNG_pHYs_SUPPORTED
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs))
    {
-      png_debug1(1, "in %s retrieval function\n", "png_get_y_pixels_per_meter");
-      if(info_ptr->phys_unit_type != PNG_RESOLUTION_METER)
-          return (0);
-      else return (info_ptr->y_pixels_per_unit);
+      png_debug1(1, "in %s retrieval function",
+          "png_get_y_pixels_per_meter");
+
+      if (info_ptr->phys_unit_type == PNG_RESOLUTION_METER)
+         return (info_ptr->y_pixels_per_unit);
    }
-#else
-   return (0);
 #endif
+
    return (0);
 }
 
 png_uint_32 PNGAPI
-png_get_pixels_per_meter(png_structp png_ptr, png_infop info_ptr)
+png_get_pixels_per_meter(png_const_structp png_ptr, png_const_infop info_ptr)
 {
-   if (png_ptr != NULL && info_ptr != NULL)
-#if defined(PNG_pHYs_SUPPORTED)
-   if (info_ptr->valid & PNG_INFO_pHYs)
+#ifdef PNG_pHYs_SUPPORTED
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs))
    {
-      png_debug1(1, "in %s retrieval function\n", "png_get_pixels_per_meter");
-      if(info_ptr->phys_unit_type != PNG_RESOLUTION_METER ||
-         info_ptr->x_pixels_per_unit != info_ptr->y_pixels_per_unit)
-          return (0);
-      else return (info_ptr->x_pixels_per_unit);
+      png_debug1(1, "in %s retrieval function", "png_get_pixels_per_meter");
+
+      if (info_ptr->phys_unit_type == PNG_RESOLUTION_METER &&
+          info_ptr->x_pixels_per_unit == info_ptr->y_pixels_per_unit)
+         return (info_ptr->x_pixels_per_unit);
    }
-#else
-   return (0);
 #endif
+
    return (0);
 }
 
 #ifdef PNG_FLOATING_POINT_SUPPORTED
 float PNGAPI
-png_get_pixel_aspect_ratio(png_structp png_ptr, png_infop info_ptr)
-   {
-   if (png_ptr != NULL && info_ptr != NULL)
-#if defined(PNG_pHYs_SUPPORTED)
-   if (info_ptr->valid & PNG_INFO_pHYs)
+png_get_pixel_aspect_ratio(png_const_structp png_ptr, png_const_infop info_ptr)
+{
+#ifdef PNG_READ_pHYs_SUPPORTED
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs))
    {
-      png_debug1(1, "in %s retrieval function\n", "png_get_aspect_ratio");
-      if (info_ptr->x_pixels_per_unit == 0)
-         return ((float)0.0);
-      else
+      png_debug1(1, "in %s retrieval function", "png_get_aspect_ratio");
+
+      if (info_ptr->x_pixels_per_unit != 0)
          return ((float)((float)info_ptr->y_pixels_per_unit
-            /(float)info_ptr->x_pixels_per_unit));
+             /(float)info_ptr->x_pixels_per_unit));
    }
-#else
-   return (0.0);
 #endif
+
    return ((float)0.0);
 }
 #endif
 
+#ifdef PNG_FIXED_POINT_SUPPORTED
+png_fixed_point PNGAPI
+png_get_pixel_aspect_ratio_fixed(png_const_structp png_ptr,
+    png_const_infop info_ptr)
+{
+#ifdef PNG_READ_pHYs_SUPPORTED
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs)
+       && info_ptr->x_pixels_per_unit > 0 && info_ptr->y_pixels_per_unit > 0
+       && info_ptr->x_pixels_per_unit <= PNG_UINT_31_MAX
+       && info_ptr->y_pixels_per_unit <= PNG_UINT_31_MAX)
+   {
+      png_fixed_point res;
+
+      png_debug1(1, "in %s retrieval function", "png_get_aspect_ratio_fixed");
+
+      /* The following casts work because a PNG 4 byte integer only has a valid
+       * range of 0..2^31-1; otherwise the cast might overflow.
+       */
+      if (png_muldiv(&res, (png_int_32)info_ptr->y_pixels_per_unit, PNG_FP_1,
+          (png_int_32)info_ptr->x_pixels_per_unit))
+         return res;
+   }
+#endif
+
+   return 0;
+}
+#endif
+
 png_int_32 PNGAPI
-png_get_x_offset_microns(png_structp png_ptr, png_infop info_ptr)
+png_get_x_offset_microns(png_const_structp png_ptr, png_const_infop info_ptr)
 {
-   if (png_ptr != NULL && info_ptr != NULL)
-#if defined(PNG_oFFs_SUPPORTED)
-   if (info_ptr->valid & PNG_INFO_oFFs)
+#ifdef PNG_oFFs_SUPPORTED
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs))
    {
-      png_debug1(1, "in %s retrieval function\n", "png_get_x_offset_microns");
-      if(info_ptr->offset_unit_type != PNG_OFFSET_MICROMETER)
-          return (0);
-      else return (info_ptr->x_offset);
+      png_debug1(1, "in %s retrieval function", "png_get_x_offset_microns");
+
+      if (info_ptr->offset_unit_type == PNG_OFFSET_MICROMETER)
+         return (info_ptr->x_offset);
    }
-#else
-   return (0);
 #endif
+
    return (0);
 }
 
 png_int_32 PNGAPI
-png_get_y_offset_microns(png_structp png_ptr, png_infop info_ptr)
+png_get_y_offset_microns(png_const_structp png_ptr, png_const_infop info_ptr)
 {
-   if (png_ptr != NULL && info_ptr != NULL)
-#if defined(PNG_oFFs_SUPPORTED)
-   if (info_ptr->valid & PNG_INFO_oFFs)
+#ifdef PNG_oFFs_SUPPORTED
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs))
    {
-      png_debug1(1, "in %s retrieval function\n", "png_get_y_offset_microns");
-      if(info_ptr->offset_unit_type != PNG_OFFSET_MICROMETER)
-          return (0);
-      else return (info_ptr->y_offset);
+      png_debug1(1, "in %s retrieval function", "png_get_y_offset_microns");
+
+      if (info_ptr->offset_unit_type == PNG_OFFSET_MICROMETER)
+         return (info_ptr->y_offset);
    }
-#else
-   return (0);
 #endif
+
    return (0);
 }
 
 png_int_32 PNGAPI
-png_get_x_offset_pixels(png_structp png_ptr, png_infop info_ptr)
+png_get_x_offset_pixels(png_const_structp png_ptr, png_const_infop info_ptr)
 {
-   if (png_ptr != NULL && info_ptr != NULL)
-#if defined(PNG_oFFs_SUPPORTED)
-   if (info_ptr->valid & PNG_INFO_oFFs)
+#ifdef PNG_oFFs_SUPPORTED
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs))
    {
-      png_debug1(1, "in %s retrieval function\n", "png_get_x_offset_microns");
-      if(info_ptr->offset_unit_type != PNG_OFFSET_PIXEL)
-          return (0);
-      else return (info_ptr->x_offset);
+      png_debug1(1, "in %s retrieval function", "png_get_x_offset_pixels");
+
+      if (info_ptr->offset_unit_type == PNG_OFFSET_PIXEL)
+         return (info_ptr->x_offset);
    }
-#else
-   return (0);
 #endif
+
    return (0);
 }
 
 png_int_32 PNGAPI
-png_get_y_offset_pixels(png_structp png_ptr, png_infop info_ptr)
+png_get_y_offset_pixels(png_const_structp png_ptr, png_const_infop info_ptr)
 {
-   if (png_ptr != NULL && info_ptr != NULL)
-#if defined(PNG_oFFs_SUPPORTED)
-   if (info_ptr->valid & PNG_INFO_oFFs)
+#ifdef PNG_oFFs_SUPPORTED
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs))
    {
-      png_debug1(1, "in %s retrieval function\n", "png_get_y_offset_microns");
-      if(info_ptr->offset_unit_type != PNG_OFFSET_PIXEL)
-          return (0);
-      else return (info_ptr->y_offset);
+      png_debug1(1, "in %s retrieval function", "png_get_y_offset_pixels");
+
+      if (info_ptr->offset_unit_type == PNG_OFFSET_PIXEL)
+         return (info_ptr->y_offset);
    }
-#else
-   return (0);
 #endif
+
    return (0);
 }
 
-#if defined(PNG_INCH_CONVERSIONS) && defined(PNG_FLOATING_POINT_SUPPORTED)
+#ifdef PNG_INCH_CONVERSIONS_SUPPORTED
+static png_uint_32
+ppi_from_ppm(png_uint_32 ppm)
+{
+#if 0
+   /* The conversion is *(2.54/100), in binary (32 digits):
+    * .00000110100000001001110101001001
+    */
+   png_uint_32 t1001, t1101;
+   ppm >>= 1;                  /* .1 */
+   t1001 = ppm + (ppm >> 3);   /* .1001 */
+   t1101 = t1001 + (ppm >> 1); /* .1101 */
+   ppm >>= 20;                 /* .000000000000000000001 */
+   t1101 += t1101 >> 15;       /* .1101000000000001101 */
+   t1001 >>= 11;               /* .000000000001001 */
+   t1001 += t1001 >> 12;       /* .000000000001001000000001001 */
+   ppm += t1001;               /* .000000000001001000001001001 */
+   ppm += t1101;               /* .110100000001001110101001001 */
+   return (ppm + 16) >> 5;/* .00000110100000001001110101001001 */
+#else
+   /* The argument is a PNG unsigned integer, so it is not permitted
+    * to be bigger than 2^31.
+    */
+   png_fixed_point result;
+   if (ppm <= PNG_UINT_31_MAX && png_muldiv(&result, (png_int_32)ppm, 127,
+       5000))
+      return result;
+
+   /* Overflow. */
+   return 0;
+#endif
+}
+
 png_uint_32 PNGAPI
-png_get_pixels_per_inch(png_structp png_ptr, png_infop info_ptr)
+png_get_pixels_per_inch(png_const_structp png_ptr, png_const_infop info_ptr)
 {
-   return ((png_uint_32)((float)png_get_pixels_per_meter(png_ptr, info_ptr)
-     *.0254 +.5));
+   return ppi_from_ppm(png_get_pixels_per_meter(png_ptr, info_ptr));
 }
 
 png_uint_32 PNGAPI
-png_get_x_pixels_per_inch(png_structp png_ptr, png_infop info_ptr)
+png_get_x_pixels_per_inch(png_const_structp png_ptr, png_const_infop info_ptr)
 {
-   return ((png_uint_32)((float)png_get_x_pixels_per_meter(png_ptr, info_ptr)
-     *.0254 +.5));
+   return ppi_from_ppm(png_get_x_pixels_per_meter(png_ptr, info_ptr));
 }
 
 png_uint_32 PNGAPI
-png_get_y_pixels_per_inch(png_structp png_ptr, png_infop info_ptr)
+png_get_y_pixels_per_inch(png_const_structp png_ptr, png_const_infop info_ptr)
+{
+   return ppi_from_ppm(png_get_y_pixels_per_meter(png_ptr, info_ptr));
+}
+
+#ifdef PNG_FIXED_POINT_SUPPORTED
+static png_fixed_point
+png_fixed_inches_from_microns(png_structp png_ptr, png_int_32 microns)
+{
+   /* Convert from metres * 1,000,000 to inches * 100,000, meters to
+    * inches is simply *(100/2.54), so we want *(10/2.54) == 500/127.
+    * Notice that this can overflow - a warning is output and 0 is
+    * returned.
+    */
+   return png_muldiv_warn(png_ptr, microns, 500, 127);
+}
+
+png_fixed_point PNGAPI
+png_get_x_offset_inches_fixed(png_structp png_ptr,
+    png_const_infop info_ptr)
 {
-   return ((png_uint_32)((float)png_get_y_pixels_per_meter(png_ptr, info_ptr)
-     *.0254 +.5));
+   return png_fixed_inches_from_microns(png_ptr,
+       png_get_x_offset_microns(png_ptr, info_ptr));
 }
+#endif
 
+#ifdef PNG_FIXED_POINT_SUPPORTED
+png_fixed_point PNGAPI
+png_get_y_offset_inches_fixed(png_structp png_ptr,
+    png_const_infop info_ptr)
+{
+   return png_fixed_inches_from_microns(png_ptr,
+       png_get_y_offset_microns(png_ptr, info_ptr));
+}
+#endif
+
+#ifdef PNG_FLOATING_POINT_SUPPORTED
 float PNGAPI
-png_get_x_offset_inches(png_structp png_ptr, png_infop info_ptr)
+png_get_x_offset_inches(png_const_structp png_ptr, png_const_infop info_ptr)
 {
-   return ((float)png_get_x_offset_microns(png_ptr, info_ptr)
-     *.00003937);
+   /* To avoid the overflow do the conversion directly in floating
+    * point.
+    */
+   return (float)(png_get_x_offset_microns(png_ptr, info_ptr) * .00003937);
 }
+#endif
 
+#ifdef PNG_FLOATING_POINT_SUPPORTED
 float PNGAPI
-png_get_y_offset_inches(png_structp png_ptr, png_infop info_ptr)
+png_get_y_offset_inches(png_const_structp png_ptr, png_const_infop info_ptr)
 {
-   return ((float)png_get_y_offset_microns(png_ptr, info_ptr)
-     *.00003937);
+   /* To avoid the overflow do the conversion directly in floating
+    * point.
+    */
+   return (float)(png_get_y_offset_microns(png_ptr, info_ptr) * .00003937);
 }
+#endif
 
-#if defined(PNG_pHYs_SUPPORTED)
+#ifdef PNG_pHYs_SUPPORTED
 png_uint_32 PNGAPI
-png_get_pHYs_dpi(png_structp png_ptr, png_infop info_ptr,
-   png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type)
+png_get_pHYs_dpi(png_const_structp png_ptr, png_const_infop info_ptr,
+    png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type)
 {
    png_uint_32 retval = 0;
 
    if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs))
    {
-      png_debug1(1, "in %s retrieval function\n", "pHYs");
+      png_debug1(1, "in %s retrieval function", "pHYs");
+
       if (res_x != NULL)
       {
          *res_x = info_ptr->x_pixels_per_unit;
          retval |= PNG_INFO_pHYs;
       }
+
       if (res_y != NULL)
       {
          *res_y = info_ptr->y_pixels_per_unit;
          retval |= PNG_INFO_pHYs;
       }
+
       if (unit_type != NULL)
       {
          *unit_type = (int)info_ptr->phys_unit_type;
          retval |= PNG_INFO_pHYs;
-         if(*unit_type == 1)
+
+         if (*unit_type == 1)
          {
             if (res_x != NULL) *res_x = (png_uint_32)(*res_x * .0254 + .50);
             if (res_y != NULL) *res_y = (png_uint_32)(*res_y * .0254 + .50);
          }
       }
    }
+
    return (retval);
 }
 #endif /* PNG_pHYs_SUPPORTED */
-#endif  /* PNG_INCH_CONVERSIONS && PNG_FLOATING_POINT_SUPPORTED */
+#endif  /* PNG_INCH_CONVERSIONS_SUPPORTED */
 
 /* png_get_channels really belongs in here, too, but it's been around longer */
 
 #endif  /* PNG_EASY_ACCESS_SUPPORTED */
 
 png_byte PNGAPI
-png_get_channels(png_structp png_ptr, png_infop info_ptr)
+png_get_channels(png_const_structp png_ptr, png_const_infop info_ptr)
 {
    if (png_ptr != NULL && info_ptr != NULL)
       return(info_ptr->channels);
-   else
-      return (0);
+
+   return (0);
 }
 
-png_bytep PNGAPI
-png_get_signature(png_structp png_ptr, png_infop info_ptr)
+png_const_bytep PNGAPI
+png_get_signature(png_const_structp png_ptr, png_infop info_ptr)
 {
    if (png_ptr != NULL && info_ptr != NULL)
       return(info_ptr->signature);
-   else
-      return (NULL);
+
+   return (NULL);
 }
 
-#if defined(PNG_bKGD_SUPPORTED)
+#ifdef PNG_bKGD_SUPPORTED
 png_uint_32 PNGAPI
-png_get_bKGD(png_structp png_ptr, png_infop info_ptr,
+png_get_bKGD(png_const_structp png_ptr, png_infop info_ptr,
    png_color_16p *background)
 {
    if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_bKGD)
-      && background != NULL)
+       && background != NULL)
    {
-      png_debug1(1, "in %s retrieval function\n", "bKGD");
+      png_debug1(1, "in %s retrieval function", "bKGD");
+
       *background = &(info_ptr->background);
       return (PNG_INFO_bKGD);
    }
+
    return (0);
 }
 #endif
 
-#if defined(PNG_cHRM_SUPPORTED)
-#ifdef PNG_FLOATING_POINT_SUPPORTED
+#ifdef PNG_cHRM_SUPPORTED
+/* The XYZ APIs were added in 1.5.5 to take advantage of the code added at the
+ * same time to correct the rgb grayscale coefficient defaults obtained from the
+ * cHRM chunk in 1.5.4
+ */
+png_uint_32 PNGFAPI
+png_get_cHRM_XYZ_fixed(png_structp png_ptr, png_const_infop info_ptr,
+    png_fixed_point *int_red_X, png_fixed_point *int_red_Y,
+    png_fixed_point *int_red_Z, png_fixed_point *int_green_X,
+    png_fixed_point *int_green_Y, png_fixed_point *int_green_Z,
+    png_fixed_point *int_blue_X, png_fixed_point *int_blue_Y,
+    png_fixed_point *int_blue_Z)
+{
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_cHRM))
+   {
+      png_xy xy;
+      png_XYZ XYZ;
+
+      png_debug1(1, "in %s retrieval function", "cHRM_XYZ");
+
+      xy.whitex = info_ptr->x_white;
+      xy.whitey = info_ptr->y_white;
+      xy.redx = info_ptr->x_red;
+      xy.redy = info_ptr->y_red;
+      xy.greenx = info_ptr->x_green;
+      xy.greeny = info_ptr->y_green;
+      xy.bluex = info_ptr->x_blue;
+      xy.bluey = info_ptr->y_blue;
+
+      /* The *_checked function handles error reporting, so just return 0 if
+       * there is a failure here.
+       */
+      if (png_XYZ_from_xy_checked(png_ptr, &XYZ, xy))
+      {
+         if (int_red_X != NULL)
+            *int_red_X = XYZ.redX;
+         if (int_red_Y != NULL)
+            *int_red_Y = XYZ.redY;
+         if (int_red_Z != NULL)
+            *int_red_Z = XYZ.redZ;
+         if (int_green_X != NULL)
+            *int_green_X = XYZ.greenX;
+         if (int_green_Y != NULL)
+            *int_green_Y = XYZ.greenY;
+         if (int_green_Z != NULL)
+            *int_green_Z = XYZ.greenZ;
+         if (int_blue_X != NULL)
+            *int_blue_X = XYZ.blueX;
+         if (int_blue_Y != NULL)
+            *int_blue_Y = XYZ.blueY;
+         if (int_blue_Z != NULL)
+            *int_blue_Z = XYZ.blueZ;
+
+         return (PNG_INFO_cHRM);
+      }
+   }
+
+   return (0);
+}
+
+#  ifdef PNG_FLOATING_POINT_SUPPORTED
 png_uint_32 PNGAPI
-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)
+png_get_cHRM(png_const_structp png_ptr, png_const_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 (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_cHRM))
    {
-      png_debug1(1, "in %s retrieval function\n", "cHRM");
+      png_debug1(1, "in %s retrieval function", "cHRM");
+
       if (white_x != NULL)
-         *white_x = (double)info_ptr->x_white;
+         *white_x = png_float(png_ptr, info_ptr->x_white, "cHRM white X");
       if (white_y != NULL)
-         *white_y = (double)info_ptr->y_white;
+         *white_y = png_float(png_ptr, info_ptr->y_white, "cHRM white Y");
       if (red_x != NULL)
-         *red_x = (double)info_ptr->x_red;
+         *red_x = png_float(png_ptr, info_ptr->x_red, "cHRM red X");
       if (red_y != NULL)
-         *red_y = (double)info_ptr->y_red;
+         *red_y = png_float(png_ptr, info_ptr->y_red, "cHRM red Y");
       if (green_x != NULL)
-         *green_x = (double)info_ptr->x_green;
+         *green_x = png_float(png_ptr, info_ptr->x_green, "cHRM green X");
       if (green_y != NULL)
-         *green_y = (double)info_ptr->y_green;
+         *green_y = png_float(png_ptr, info_ptr->y_green, "cHRM green Y");
       if (blue_x != NULL)
-         *blue_x = (double)info_ptr->x_blue;
+         *blue_x = png_float(png_ptr, info_ptr->x_blue, "cHRM blue X");
       if (blue_y != NULL)
-         *blue_y = (double)info_ptr->y_blue;
+         *blue_y = png_float(png_ptr, info_ptr->y_blue, "cHRM blue Y");
       return (PNG_INFO_cHRM);
    }
+
    return (0);
 }
-#endif
-#ifdef PNG_FIXED_POINT_SUPPORTED
+
 png_uint_32 PNGAPI
-png_get_cHRM_fixed(png_structp png_ptr, png_infop info_ptr,
-   png_fixed_point *white_x, png_fixed_point *white_y, png_fixed_point *red_x,
-   png_fixed_point *red_y, png_fixed_point *green_x, png_fixed_point *green_y,
-   png_fixed_point *blue_x, png_fixed_point *blue_y)
+png_get_cHRM_XYZ(png_structp png_ptr, png_const_infop info_ptr,
+   double *red_X, double *red_Y, double *red_Z, double *green_X,
+   double *green_Y, double *green_Z, double *blue_X, double *blue_Y,
+   double *blue_Z)
 {
+   png_XYZ XYZ;
+
+   if (png_get_cHRM_XYZ_fixed(png_ptr, info_ptr,
+      &XYZ.redX, &XYZ.redY, &XYZ.redZ, &XYZ.greenX, &XYZ.greenY, &XYZ.greenZ,
+      &XYZ.blueX, &XYZ.blueY, &XYZ.blueZ) & PNG_INFO_cHRM)
+   {
+      if (red_X != NULL)
+         *red_X = png_float(png_ptr, XYZ.redX, "cHRM red X");
+      if (red_Y != NULL)
+         *red_Y = png_float(png_ptr, XYZ.redY, "cHRM red Y");
+      if (red_Z != NULL)
+         *red_Z = png_float(png_ptr, XYZ.redZ, "cHRM red Z");
+      if (green_X != NULL)
+         *green_X = png_float(png_ptr, XYZ.greenX, "cHRM green X");
+      if (green_Y != NULL)
+         *green_Y = png_float(png_ptr, XYZ.greenY, "cHRM green Y");
+      if (green_Z != NULL)
+         *green_Z = png_float(png_ptr, XYZ.greenZ, "cHRM green Z");
+      if (blue_X != NULL)
+         *blue_X = png_float(png_ptr, XYZ.blueX, "cHRM blue X");
+      if (blue_Y != NULL)
+         *blue_Y = png_float(png_ptr, XYZ.blueY, "cHRM blue Y");
+      if (blue_Z != NULL)
+         *blue_Z = png_float(png_ptr, XYZ.blueZ, "cHRM blue Z");
+      return (PNG_INFO_cHRM);
+   }
+
+   return (0);
+}
+#  endif
+
+#  ifdef PNG_FIXED_POINT_SUPPORTED
+png_uint_32 PNGAPI
+png_get_cHRM_fixed(png_const_structp png_ptr, png_const_infop info_ptr,
+    png_fixed_point *white_x, png_fixed_point *white_y, png_fixed_point *red_x,
+    png_fixed_point *red_y, png_fixed_point *green_x, png_fixed_point *green_y,
+    png_fixed_point *blue_x, png_fixed_point *blue_y)
+{
+   png_debug1(1, "in %s retrieval function", "cHRM");
+
    if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_cHRM))
    {
-      png_debug1(1, "in %s retrieval function\n", "cHRM");
       if (white_x != NULL)
-         *white_x = info_ptr->int_x_white;
+         *white_x = info_ptr->x_white;
       if (white_y != NULL)
-         *white_y = info_ptr->int_y_white;
+         *white_y = info_ptr->y_white;
       if (red_x != NULL)
-         *red_x = info_ptr->int_x_red;
+         *red_x = info_ptr->x_red;
       if (red_y != NULL)
-         *red_y = info_ptr->int_y_red;
+         *red_y = info_ptr->y_red;
       if (green_x != NULL)
-         *green_x = info_ptr->int_x_green;
+         *green_x = info_ptr->x_green;
       if (green_y != NULL)
-         *green_y = info_ptr->int_y_green;
+         *green_y = info_ptr->y_green;
       if (blue_x != NULL)
-         *blue_x = info_ptr->int_x_blue;
+         *blue_x = info_ptr->x_blue;
       if (blue_y != NULL)
-         *blue_y = info_ptr->int_y_blue;
+         *blue_y = info_ptr->y_blue;
       return (PNG_INFO_cHRM);
    }
+
    return (0);
 }
-#endif
+#  endif
 #endif
 
-#if defined(PNG_gAMA_SUPPORTED)
-#ifdef PNG_FLOATING_POINT_SUPPORTED
-png_uint_32 PNGAPI
-png_get_gAMA(png_structp png_ptr, png_infop info_ptr, double *file_gamma)
+#ifdef PNG_gAMA_SUPPORTED
+png_uint_32 PNGFAPI
+png_get_gAMA_fixed(png_const_structp png_ptr, png_const_infop info_ptr,
+    png_fixed_point *file_gamma)
 {
+   png_debug1(1, "in %s retrieval function", "gAMA");
+
    if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_gAMA)
-      && file_gamma != NULL)
+       && file_gamma != NULL)
    {
-      png_debug1(1, "in %s retrieval function\n", "gAMA");
-      *file_gamma = (double)info_ptr->gamma;
+      *file_gamma = info_ptr->gamma;
       return (PNG_INFO_gAMA);
    }
+
    return (0);
 }
-#endif
-#ifdef PNG_FIXED_POINT_SUPPORTED
+#  ifdef PNG_FLOATING_POINT_SUPPORTED
 png_uint_32 PNGAPI
-png_get_gAMA_fixed(png_structp png_ptr, png_infop info_ptr,
-    png_fixed_point *int_file_gamma)
+png_get_gAMA(png_const_structp png_ptr, png_const_infop info_ptr,
+    double *file_gamma)
 {
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_gAMA)
-      && int_file_gamma != NULL)
-   {
-      png_debug1(1, "in %s retrieval function\n", "gAMA");
-      *int_file_gamma = info_ptr->int_gamma;
-      return (PNG_INFO_gAMA);
-   }
-   return (0);
+   png_fixed_point igamma;
+   png_uint_32 ok = png_get_gAMA_fixed(png_ptr, info_ptr, &igamma);
+
+   if (ok)
+      *file_gamma = png_float(png_ptr, igamma, "png_get_gAMA");
+
+   return ok;
 }
-#endif
+
+#  endif
 #endif
 
-#if defined(PNG_sRGB_SUPPORTED)
+#ifdef PNG_sRGB_SUPPORTED
 png_uint_32 PNGAPI
-png_get_sRGB(png_structp png_ptr, png_infop info_ptr, int *file_srgb_intent)
+png_get_sRGB(png_const_structp png_ptr, png_const_infop info_ptr,
+    int *file_srgb_intent)
 {
+   png_debug1(1, "in %s retrieval function", "sRGB");
+
    if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_sRGB)
-      && file_srgb_intent != NULL)
+       && file_srgb_intent != NULL)
    {
-      png_debug1(1, "in %s retrieval function\n", "sRGB");
       *file_srgb_intent = (int)info_ptr->srgb_intent;
       return (PNG_INFO_sRGB);
    }
+
    return (0);
 }
 #endif
 
-#if defined(PNG_iCCP_SUPPORTED)
+#ifdef PNG_iCCP_SUPPORTED
 png_uint_32 PNGAPI
-png_get_iCCP(png_structp png_ptr, png_infop info_ptr,
-             png_charpp name, int *compression_type,
-             png_charpp profile, png_uint_32 *proflen)
+png_get_iCCP(png_const_structp png_ptr, png_const_infop info_ptr,
+    png_charpp name, int *compression_type,
+    png_bytepp profile, png_uint_32 *proflen)
 {
+   png_debug1(1, "in %s retrieval function", "iCCP");
+
    if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_iCCP)
-      && name != NULL && profile != NULL && proflen != NULL)
+       && name != NULL && compression_type != NULL && profile != NULL &&
+		 proflen != NULL)
    {
-      png_debug1(1, "in %s retrieval function\n", "iCCP");
       *name = info_ptr->iccp_name;
       *profile = info_ptr->iccp_profile;
-      /* compression_type is a dummy so the API won't have to change
-         if we introduce multiple compression types later. */
-      *proflen = (int)info_ptr->iccp_proflen;
-      *compression_type = (int)info_ptr->iccp_compression;
+      /* Compression_type is a dummy so the API won't have to change
+       * if we introduce multiple compression types later.
+       */
+      *proflen = info_ptr->iccp_proflen;
+      *compression_type = info_ptr->iccp_compression;
       return (PNG_INFO_iCCP);
    }
+
    return (0);
 }
 #endif
 
-#if defined(PNG_sPLT_SUPPORTED)
+#ifdef PNG_sPLT_SUPPORTED
 png_uint_32 PNGAPI
-png_get_sPLT(png_structp png_ptr, png_infop info_ptr,
-             png_sPLT_tpp spalettes)
+png_get_sPLT(png_const_structp png_ptr, png_const_infop info_ptr,
+    png_sPLT_tpp spalettes)
 {
    if (png_ptr != NULL && info_ptr != NULL && spalettes != NULL)
-     *spalettes = info_ptr->splt_palettes;
-   return ((png_uint_32)info_ptr->splt_palettes_num);
+   {
+      *spalettes = info_ptr->splt_palettes;
+      return ((png_uint_32)info_ptr->splt_palettes_num);
+   }
+
+   return (0);
 }
 #endif
 
-#if defined(PNG_hIST_SUPPORTED)
+#ifdef PNG_hIST_SUPPORTED
 png_uint_32 PNGAPI
-png_get_hIST(png_structp png_ptr, png_infop info_ptr, png_uint_16p *hist)
+png_get_hIST(png_const_structp png_ptr, png_const_infop info_ptr,
+    png_uint_16p *hist)
 {
+   png_debug1(1, "in %s retrieval function", "hIST");
+
    if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_hIST)
-      && hist != NULL)
+       && 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 PNGAPI
 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)
+    png_uint_32 *width, png_uint_32 *height, int *bit_depth,
+    int *color_type, int *interlace_type, int *compression_type,
+    int *filter_type)
 
 {
-   if (png_ptr != NULL && info_ptr != NULL && width != NULL && height != NULL &&
-      bit_depth != NULL && color_type != NULL)
-   {
-      int pixel_depth, channels;
-      png_uint_32 rowbytes_per_pixel;
-
-      png_debug1(1, "in %s retrieval function\n", "IHDR");
-      *width = info_ptr->width;
-      *height = info_ptr->height;
-      *bit_depth = info_ptr->bit_depth;
-      if (info_ptr->bit_depth < 1 || info_ptr->bit_depth > 16)
-        png_error(png_ptr, "Invalid bit depth");
-      *color_type = info_ptr->color_type;
-      if (info_ptr->color_type > 6)
-        png_error(png_ptr, "Invalid 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;
-
-      /* check for potential overflow of rowbytes */
-      if (*color_type == PNG_COLOR_TYPE_PALETTE)
-         channels = 1;
-      else if (*color_type & PNG_COLOR_MASK_COLOR)
-         channels = 3;
-      else
-         channels = 1;
-      if (*color_type & PNG_COLOR_MASK_ALPHA)
-         channels++;
-      pixel_depth = *bit_depth * channels;
-      rowbytes_per_pixel = (pixel_depth + 7) >> 3;
-      if (width == 0 || *width > PNG_MAX_UINT)
-        png_error(png_ptr, "Invalid image width");
-      if (height == 0 || *height > PNG_MAX_UINT)
-        png_error(png_ptr, "Invalid image height");
-      if (*width > PNG_MAX_UINT/rowbytes_per_pixel - 64)
-      {
-         png_error(png_ptr,
-            "Width too large for libpng to process image data.");
-      }
-      return (1);
-   }
-   return (0);
+   png_debug1(1, "in %s retrieval function", "IHDR");
+
+   if (png_ptr == NULL || info_ptr == NULL || width == NULL ||
+       height == NULL || bit_depth == NULL || color_type == NULL)
+      return (0);
+
+   *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;
+
+   /* This is redundant if we can be sure that the info_ptr values were all
+    * assigned in png_set_IHDR().  We do the check anyhow in case an
+    * application has ignored our advice not to mess with the members
+    * of info_ptr directly.
+    */
+   png_check_IHDR (png_ptr, info_ptr->width, info_ptr->height,
+       info_ptr->bit_depth, info_ptr->color_type, info_ptr->interlace_type,
+       info_ptr->compression_type, info_ptr->filter_type);
+
+   return (1);
 }
 
-#if defined(PNG_oFFs_SUPPORTED)
+#ifdef PNG_oFFs_SUPPORTED
 png_uint_32 PNGAPI
-png_get_oFFs(png_structp png_ptr, png_infop info_ptr,
-   png_int_32 *offset_x, png_int_32 *offset_y, int *unit_type)
+png_get_oFFs(png_const_structp png_ptr, png_const_infop info_ptr,
+    png_int_32 *offset_x, png_int_32 *offset_y, int *unit_type)
 {
+   png_debug1(1, "in %s retrieval function", "oFFs");
+
    if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs)
-      && offset_x != NULL && offset_y != NULL && unit_type != NULL)
+       && 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_pCAL_SUPPORTED)
+#ifdef PNG_pCAL_SUPPORTED
 png_uint_32 PNGAPI
-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)
+png_get_pCAL(png_const_structp png_ptr, png_const_infop info_ptr,
+    png_charp *purpose, png_int_32 *X0, png_int_32 *X1, int *type, int *nparams,
+    png_charp *units, png_charpp *params)
 {
+   png_debug1(1, "in %s retrieval function", "pCAL");
+
    if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pCAL)
-      && purpose != NULL && X0 != NULL && X1 != NULL && type != NULL &&
-      nparams != NULL && units != NULL && params != NULL)
+       && 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;
@@ -622,306 +812,313 @@ png_get_pCAL(png_structp png_ptr, png_infop info_ptr,
       *params = info_ptr->pcal_params;
       return (PNG_INFO_pCAL);
    }
+
    return (0);
 }
 #endif
 
-#if defined(PNG_sCAL_SUPPORTED)
-#ifdef PNG_FLOATING_POINT_SUPPORTED
+#ifdef PNG_sCAL_SUPPORTED
+#  ifdef PNG_FIXED_POINT_SUPPORTED
+#    ifdef PNG_FLOATING_ARITHMETIC_SUPPORTED
 png_uint_32 PNGAPI
-png_get_sCAL(png_structp png_ptr, png_infop info_ptr,
-             int *unit, double *width, double *height)
+png_get_sCAL_fixed(png_structp png_ptr, png_const_infop info_ptr,
+    int *unit, png_fixed_point *width, png_fixed_point *height)
 {
-    if (png_ptr != NULL && info_ptr != NULL &&
+   if (png_ptr != NULL && info_ptr != NULL &&
        (info_ptr->valid & PNG_INFO_sCAL))
-    {
-        *unit = info_ptr->scal_unit;
-        *width = info_ptr->scal_pixel_width;
-        *height = info_ptr->scal_pixel_height;
-        return (PNG_INFO_sCAL);
-    }
-    return(0);
+   {
+      *unit = info_ptr->scal_unit;
+      /*TODO: make this work without FP support */
+      *width = png_fixed(png_ptr, atof(info_ptr->scal_s_width), "sCAL width");
+      *height = png_fixed(png_ptr, atof(info_ptr->scal_s_height),
+         "sCAL height");
+      return (PNG_INFO_sCAL);
+   }
+
+   return(0);
 }
-#else
-#ifdef PNG_FIXED_POINT_SUPPORTED
+#    endif /* FLOATING_ARITHMETIC */
+#  endif /* FIXED_POINT */
+#  ifdef PNG_FLOATING_POINT_SUPPORTED
 png_uint_32 PNGAPI
-png_get_sCAL_s(png_structp png_ptr, png_infop info_ptr,
-             int *unit, png_charpp width, png_charpp height)
+png_get_sCAL(png_const_structp png_ptr, png_const_infop info_ptr,
+    int *unit, double *width, double *height)
 {
-    if (png_ptr != NULL && info_ptr != NULL &&
+   if (png_ptr != NULL && info_ptr != NULL &&
        (info_ptr->valid & PNG_INFO_sCAL))
-    {
-        *unit = info_ptr->scal_unit;
-        *width = info_ptr->scal_s_width;
-        *height = info_ptr->scal_s_height;
-        return (PNG_INFO_sCAL);
-    }
-    return(0);
+   {
+      *unit = info_ptr->scal_unit;
+      *width = atof(info_ptr->scal_s_width);
+      *height = atof(info_ptr->scal_s_height);
+      return (PNG_INFO_sCAL);
+   }
+
+   return(0);
 }
-#endif
-#endif
-#endif
+#  endif /* FLOATING POINT */
+png_uint_32 PNGAPI
+png_get_sCAL_s(png_const_structp png_ptr, png_const_infop info_ptr,
+    int *unit, png_charpp width, png_charpp height)
+{
+   if (png_ptr != NULL && info_ptr != NULL &&
+       (info_ptr->valid & PNG_INFO_sCAL))
+   {
+      *unit = info_ptr->scal_unit;
+      *width = info_ptr->scal_s_width;
+      *height = info_ptr->scal_s_height;
+      return (PNG_INFO_sCAL);
+   }
+
+   return(0);
+}
+#endif /* sCAL */
 
-#if defined(PNG_pHYs_SUPPORTED)
+#ifdef PNG_pHYs_SUPPORTED
 png_uint_32 PNGAPI
-png_get_pHYs(png_structp png_ptr, png_infop info_ptr,
-   png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type)
+png_get_pHYs(png_const_structp png_ptr, png_const_infop info_ptr,
+    png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type)
 {
    png_uint_32 retval = 0;
 
+   png_debug1(1, "in %s retrieval function", "pHYs");
+
    if (png_ptr != NULL && info_ptr != NULL &&
-      (info_ptr->valid & PNG_INFO_pHYs))
+       (info_ptr->valid & PNG_INFO_pHYs))
    {
-      png_debug1(1, "in %s retrieval function\n", "pHYs");
       if (res_x != NULL)
       {
          *res_x = info_ptr->x_pixels_per_unit;
          retval |= PNG_INFO_pHYs;
       }
+
       if (res_y != NULL)
       {
          *res_y = info_ptr->y_pixels_per_unit;
          retval |= PNG_INFO_pHYs;
       }
+
       if (unit_type != NULL)
       {
          *unit_type = (int)info_ptr->phys_unit_type;
          retval |= PNG_INFO_pHYs;
       }
    }
+
    return (retval);
 }
-#endif
+#endif /* pHYs */
 
 png_uint_32 PNGAPI
-png_get_PLTE(png_structp png_ptr, png_infop info_ptr, png_colorp *palette,
-   int *num_palette)
+png_get_PLTE(png_const_structp png_ptr, png_const_infop info_ptr,
+    png_colorp *palette, int *num_palette)
 {
+   png_debug1(1, "in %s retrieval function", "PLTE");
+
    if (png_ptr != NULL && 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);
+      png_debug1(3, "num_palette = %d", *num_palette);
       return (PNG_INFO_PLTE);
    }
+
    return (0);
 }
 
-#if defined(PNG_sBIT_SUPPORTED)
+#ifdef PNG_sBIT_SUPPORTED
 png_uint_32 PNGAPI
-png_get_sBIT(png_structp png_ptr, png_infop info_ptr, png_color_8p *sig_bit)
+png_get_sBIT(png_const_structp png_ptr, png_infop info_ptr,
+    png_color_8p *sig_bit)
 {
+   png_debug1(1, "in %s retrieval function", "sBIT");
+
    if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_sBIT)
-      && sig_bit != NULL)
+       && 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_TEXT_SUPPORTED)
+#ifdef PNG_TEXT_SUPPORTED
 png_uint_32 PNGAPI
-png_get_text(png_structp png_ptr, png_infop info_ptr, png_textp *text_ptr,
-   int *num_text)
+png_get_text(png_const_structp png_ptr, png_const_infop info_ptr,
+    png_textp *text_ptr, int *num_text)
 {
    if (png_ptr != NULL && info_ptr != NULL && info_ptr->num_text > 0)
    {
-      png_debug1(1, "in %s retrieval function\n",
-         (png_ptr->chunk_name[0] == '\0' ? "text"
-             : (png_const_charp)png_ptr->chunk_name));
+      png_debug1(1, "in 0x%lx retrieval function",
+         (unsigned long)png_ptr->chunk_name);
+
       if (text_ptr != NULL)
          *text_ptr = info_ptr->text;
+
       if (num_text != NULL)
          *num_text = info_ptr->num_text;
+
       return ((png_uint_32)info_ptr->num_text);
    }
+
    if (num_text != NULL)
-     *num_text = 0;
+      *num_text = 0;
+
    return(0);
 }
 #endif
 
-#if defined(PNG_tIME_SUPPORTED)
+#ifdef PNG_tIME_SUPPORTED
 png_uint_32 PNGAPI
-png_get_tIME(png_structp png_ptr, png_infop info_ptr, png_timep *mod_time)
+png_get_tIME(png_const_structp png_ptr, png_infop info_ptr, png_timep *mod_time)
 {
+   png_debug1(1, "in %s retrieval function", "tIME");
+
    if (png_ptr != NULL && 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_tRNS_SUPPORTED)
+#ifdef PNG_tRNS_SUPPORTED
 png_uint_32 PNGAPI
-png_get_tRNS(png_structp png_ptr, png_infop info_ptr,
-   png_bytep *trans, int *num_trans, png_color_16p *trans_values)
+png_get_tRNS(png_const_structp png_ptr, png_infop info_ptr,
+    png_bytep *trans_alpha, int *num_trans, png_color_16p *trans_color)
 {
    png_uint_32 retval = 0;
    if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_tRNS))
    {
-      png_debug1(1, "in %s retrieval function\n", "tRNS");
+      png_debug1(1, "in %s retrieval function", "tRNS");
+
       if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
       {
-          if (trans != NULL)
-          {
-             *trans = info_ptr->trans;
-             retval |= PNG_INFO_tRNS;
-          }
-          if (trans_values != NULL)
-             *trans_values = &(info_ptr->trans_values);
+         if (trans_alpha != NULL)
+         {
+            *trans_alpha = info_ptr->trans_alpha;
+            retval |= PNG_INFO_tRNS;
+         }
+
+         if (trans_color != NULL)
+            *trans_color = &(info_ptr->trans_color);
       }
+
       else /* if (info_ptr->color_type != PNG_COLOR_TYPE_PALETTE) */
       {
-          if (trans_values != NULL)
-          {
-             *trans_values = &(info_ptr->trans_values);
-             retval |= PNG_INFO_tRNS;
-          }
-          if(trans != NULL)
-             *trans = NULL;
+         if (trans_color != NULL)
+         {
+            *trans_color = &(info_ptr->trans_color);
+            retval |= PNG_INFO_tRNS;
+         }
+
+         if (trans_alpha != NULL)
+            *trans_alpha = NULL;
       }
-      if(num_trans != NULL)
+
+      if (num_trans != NULL)
       {
          *num_trans = info_ptr->num_trans;
          retval |= PNG_INFO_tRNS;
       }
    }
+
    return (retval);
 }
 #endif
 
-#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
-png_uint_32 PNGAPI
-png_get_unknown_chunks(png_structp png_ptr, png_infop info_ptr,
-             png_unknown_chunkpp unknowns)
+#ifdef PNG_UNKNOWN_CHUNKS_SUPPORTED
+int PNGAPI
+png_get_unknown_chunks(png_const_structp png_ptr, png_const_infop info_ptr,
+    png_unknown_chunkpp unknowns)
 {
    if (png_ptr != NULL && info_ptr != NULL && unknowns != NULL)
-     *unknowns = info_ptr->unknown_chunks;
-   return ((png_uint_32)info_ptr->unknown_chunks_num);
+   {
+      *unknowns = info_ptr->unknown_chunks;
+      return info_ptr->unknown_chunks_num;
+   }
+
+   return (0);
 }
 #endif
 
-#if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
+#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
 png_byte PNGAPI
-png_get_rgb_to_gray_status (png_structp png_ptr)
+png_get_rgb_to_gray_status (png_const_structp png_ptr)
 {
-   return (png_byte)(png_ptr? png_ptr->rgb_to_gray_status : 0);
+   return (png_byte)(png_ptr ? png_ptr->rgb_to_gray_status : 0);
 }
 #endif
 
-#if defined(PNG_USER_CHUNKS_SUPPORTED)
+#ifdef PNG_USER_CHUNKS_SUPPORTED
 png_voidp PNGAPI
-png_get_user_chunk_ptr(png_structp png_ptr)
+png_get_user_chunk_ptr(png_const_structp png_ptr)
 {
-   return (png_ptr? png_ptr->user_chunk_ptr : NULL);
+   return (png_ptr ? png_ptr->user_chunk_ptr : NULL);
 }
 #endif
 
+png_size_t PNGAPI
+png_get_compression_buffer_size(png_const_structp png_ptr)
+{
+   return (png_ptr ? png_ptr->zbuf_size : 0);
+}
 
+#ifdef PNG_SET_USER_LIMITS_SUPPORTED
+/* These functions were added to libpng 1.2.6 and were enabled
+ * by default in libpng-1.4.0 */
 png_uint_32 PNGAPI
-png_get_compression_buffer_size(png_structp png_ptr)
+png_get_user_width_max (png_const_structp png_ptr)
 {
-   return (png_uint_32)(png_ptr? png_ptr->zbuf_size : 0L);
+   return (png_ptr ? png_ptr->user_width_max : 0);
 }
 
-
-#ifndef PNG_1_0_X
-#ifdef PNG_ASSEMBLER_CODE_SUPPORTED
-/* this function was added to libpng 1.2.0 and should exist by default */
 png_uint_32 PNGAPI
-png_get_asm_flags (png_structp png_ptr)
+png_get_user_height_max (png_const_structp png_ptr)
 {
-    return (png_uint_32)(png_ptr? png_ptr->asm_flags : 0L);
+   return (png_ptr ? png_ptr->user_height_max : 0);
 }
 
-/* this function was added to libpng 1.2.0 and should exist by default */
+/* This function was added to libpng 1.4.0 */
 png_uint_32 PNGAPI
-png_get_asm_flagmask (int flag_select)
+png_get_chunk_cache_max (png_const_structp png_ptr)
 {
-    png_uint_32 settable_asm_flags = 0;
-
-    if (flag_select & PNG_SELECT_READ)
-        settable_asm_flags |=
-          PNG_ASM_FLAG_MMX_READ_COMBINE_ROW  |
-          PNG_ASM_FLAG_MMX_READ_INTERLACE    |
-          PNG_ASM_FLAG_MMX_READ_FILTER_SUB   |
-          PNG_ASM_FLAG_MMX_READ_FILTER_UP    |
-          PNG_ASM_FLAG_MMX_READ_FILTER_AVG   |
-          PNG_ASM_FLAG_MMX_READ_FILTER_PAETH ;
-          /* no non-MMX flags yet */
-
-#if 0
-    /* GRR:  no write-flags yet, either, but someday... */
-    if (flag_select & PNG_SELECT_WRITE)
-        settable_asm_flags |=
-          PNG_ASM_FLAG_MMX_WRITE_ [whatever] ;
-#endif /* 0 */
-
-    return settable_asm_flags;  /* _theoretically_ settable capabilities only */
+   return (png_ptr ? png_ptr->user_chunk_cache_max : 0);
 }
-#endif /* PNG_ASSEMBLER_CODE_SUPPORTED */
 
+/* This function was added to libpng 1.4.1 */
+png_alloc_size_t PNGAPI
+png_get_chunk_malloc_max (png_const_structp png_ptr)
+{
+   return (png_ptr ? png_ptr->user_chunk_malloc_max : 0);
+}
+#endif /* ?PNG_SET_USER_LIMITS_SUPPORTED */
 
-#if defined(PNG_ASSEMBLER_CODE_SUPPORTED)
-    /* GRR:  could add this:   && defined(PNG_MMX_CODE_SUPPORTED) */
-/* this function was added to libpng 1.2.0 */
+/* These functions were added to libpng 1.4.0 */
+#ifdef PNG_IO_STATE_SUPPORTED
 png_uint_32 PNGAPI
-png_get_mmx_flagmask (int flag_select, int *compilerID)
+png_get_io_state (png_structp png_ptr)
 {
-    png_uint_32 settable_mmx_flags = 0;
-
-    if (flag_select & PNG_SELECT_READ)
-        settable_mmx_flags |=
-          PNG_ASM_FLAG_MMX_READ_COMBINE_ROW  |
-          PNG_ASM_FLAG_MMX_READ_INTERLACE    |
-          PNG_ASM_FLAG_MMX_READ_FILTER_SUB   |
-          PNG_ASM_FLAG_MMX_READ_FILTER_UP    |
-          PNG_ASM_FLAG_MMX_READ_FILTER_AVG   |
-          PNG_ASM_FLAG_MMX_READ_FILTER_PAETH ;
-#if 0
-    /* GRR:  no MMX write support yet, but someday... */
-    if (flag_select & PNG_SELECT_WRITE)
-        settable_mmx_flags |=
-          PNG_ASM_FLAG_MMX_WRITE_ [whatever] ;
-#endif /* 0 */
-
-    if (compilerID != NULL) {
-#ifdef PNG_USE_PNGVCRD
-        *compilerID = 1;    /* MSVC */
-#else
-#ifdef PNG_USE_PNGGCCRD
-        *compilerID = 2;    /* gcc/gas */
-#else
-        *compilerID = -1;   /* unknown (i.e., no asm/MMX code compiled) */
-#endif
-#endif
-    }
-
-    return settable_mmx_flags;  /* _theoretically_ settable capabilities only */
+   return png_ptr->io_state;
 }
 
-/* this function was added to libpng 1.2.0 */
-png_byte PNGAPI
-png_get_mmx_bitdepth_threshold (png_structp png_ptr)
+png_uint_32 PNGAPI
+png_get_io_chunk_type (png_const_structp png_ptr)
 {
-    return (png_byte)(png_ptr? png_ptr->mmx_bitdepth_threshold : 0);
+   return png_ptr->chunk_name;
 }
 
-/* this function was added to libpng 1.2.0 */
-png_uint_32 PNGAPI
-png_get_mmx_rowbytes_threshold (png_structp png_ptr)
+png_const_bytep PNGAPI
+png_get_io_chunk_name (png_structp png_ptr)
 {
-    return (png_uint_32)(png_ptr? png_ptr->mmx_rowbytes_threshold : 0L);
+   PNG_CSTRING_FROM_CHUNK(png_ptr->io_chunk_string, png_ptr->chunk_name);
+   return png_ptr->io_chunk_string;
 }
-#endif /* PNG_ASSEMBLER_CODE_SUPPORTED */
-#endif /* PNG_1_0_X */
+#endif /* ?PNG_IO_STATE_SUPPORTED */
+
+#endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */