Update bundled libpng to version 1.6.17

Merged in the upstream version, which obsoleted many of the local
patches. The remaining diff to clean 1.6.17 is archived in the
qtpatches.diff file.

Change-Id: I5065435dc5a922d3f4a46eb37a23a4877dde2ee6
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@theqtcompany.com>

1 files changed, 98 insertions, 157 deletions

diff --git a/src/3rdparty/libpng/pngwtran.c b/src/3rdparty/libpng/pngwtran.c
index 96608efcb4..db82e27bce 100644
--- a/src/3rdparty/libpng/pngwtran.c
+++ b/src/3rdparty/libpng/pngwtran.c
@@ -1,8 +1,8 @@
 
 /* pngwtran.c - transforms the data in a row for PNG writers
  *
- * Last changed in libpng 1.5.6 [November 3, 2011]
- * Copyright (c) 1998-2011 Glenn Randers-Pehrson
+ * Last changed in libpng 1.6.17 [March 26, 2015]
+ * Copyright (c) 1998-2015 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.)
  *
@@ -14,90 +14,14 @@
 #include "pngpriv.h"
 
 #ifdef PNG_WRITE_SUPPORTED
-
 #ifdef PNG_WRITE_TRANSFORMS_SUPPORTED
-/* Transform the data according to the user's wishes.  The order of
- * transformations is significant.
- */
-void /* PRIVATE */
-png_do_write_transformations(png_structp png_ptr, png_row_infop row_info)
-{
-   png_debug(1, "in png_do_write_transformations");
-
-   if (png_ptr == NULL)
-      return;
-
-#ifdef PNG_WRITE_USER_TRANSFORM_SUPPORTED
-   if (png_ptr->transformations & PNG_USER_TRANSFORM)
-      if (png_ptr->write_user_transform_fn != NULL)
-         (*(png_ptr->write_user_transform_fn)) /* User write transform
-                                                 function */
-             (png_ptr,  /* png_ptr */
-             row_info,  /* row_info: */
-                /*  png_uint_32 width;       width of row */
-                /*  png_size_t 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) */
-             png_ptr->row_buf + 1);      /* start of pixel data for row */
-#endif
-
-#ifdef PNG_WRITE_FILLER_SUPPORTED
-   if (png_ptr->transformations & PNG_FILLER)
-      png_do_strip_channel(row_info, png_ptr->row_buf + 1,
-         !(png_ptr->flags & PNG_FLAG_FILLER_AFTER));
-#endif
-
-#ifdef PNG_WRITE_PACKSWAP_SUPPORTED
-   if (png_ptr->transformations & PNG_PACKSWAP)
-      png_do_packswap(row_info, png_ptr->row_buf + 1);
-#endif
-
-#ifdef PNG_WRITE_PACK_SUPPORTED
-   if (png_ptr->transformations & PNG_PACK)
-      png_do_pack(row_info, png_ptr->row_buf + 1,
-          (png_uint_32)png_ptr->bit_depth);
-#endif
-
-#ifdef PNG_WRITE_SWAP_SUPPORTED
-   if (png_ptr->transformations & PNG_SWAP_BYTES)
-      png_do_swap(row_info, png_ptr->row_buf + 1);
-#endif
-
-#ifdef PNG_WRITE_SHIFT_SUPPORTED
-   if (png_ptr->transformations & PNG_SHIFT)
-      png_do_shift(row_info, png_ptr->row_buf + 1,
-          &(png_ptr->shift));
-#endif
-
-#ifdef PNG_WRITE_SWAP_ALPHA_SUPPORTED
-   if (png_ptr->transformations & PNG_SWAP_ALPHA)
-      png_do_write_swap_alpha(row_info, png_ptr->row_buf + 1);
-#endif
-
-#ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED
-   if (png_ptr->transformations & PNG_INVERT_ALPHA)
-      png_do_write_invert_alpha(row_info, png_ptr->row_buf + 1);
-#endif
-
-#ifdef PNG_WRITE_BGR_SUPPORTED
-   if (png_ptr->transformations & PNG_BGR)
-      png_do_bgr(row_info, png_ptr->row_buf + 1);
-#endif
-
-#ifdef PNG_WRITE_INVERT_SUPPORTED
-   if (png_ptr->transformations & PNG_INVERT_MONO)
-      png_do_invert(row_info, png_ptr->row_buf + 1);
-#endif
-}
 
 #ifdef PNG_WRITE_PACK_SUPPORTED
 /* Pack pixels into bytes.  Pass the true bit depth in bit_depth.  The
  * row_info bit depth should be 8 (one pixel per byte).  The channels
  * should be 1 (this only happens on grayscale and paletted images).
  */
-void /* PRIVATE */
+static void
 png_do_pack(png_row_infop row_info, png_bytep row, png_uint_32 bit_depth)
 {
    png_debug(1, "in png_do_pack");
@@ -242,7 +166,7 @@ png_do_pack(png_row_infop row_info, png_bytep row, png_uint_32 bit_depth)
  * would pass 3 as bit_depth, and this routine would translate the
  * data to 0 to 15.
  */
-void /* PRIVATE */
+static void
 png_do_shift(png_row_infop row_info, png_bytep row,
     png_const_color_8p bit_depth)
 {
@@ -253,7 +177,7 @@ png_do_shift(png_row_infop row_info, png_bytep row,
       int shift_start[4], shift_dec[4];
       int channels = 0;
 
-      if (row_info->color_type & PNG_COLOR_MASK_COLOR)
+      if ((row_info->color_type & PNG_COLOR_MASK_COLOR) != 0)
       {
          shift_start[channels] = row_info->bit_depth - bit_depth->red;
          shift_dec[channels] = bit_depth->red;
@@ -275,7 +199,7 @@ png_do_shift(png_row_infop row_info, png_bytep row,
          channels++;
       }
 
-      if (row_info->color_type & PNG_COLOR_MASK_ALPHA)
+      if ((row_info->color_type & PNG_COLOR_MASK_ALPHA) != 0)
       {
          shift_start[channels] = row_info->bit_depth - bit_depth->alpha;
          shift_dec[channels] = bit_depth->alpha;
@@ -287,7 +211,7 @@ png_do_shift(png_row_infop row_info, png_bytep row,
       {
          png_bytep bp = row;
          png_size_t i;
-         png_byte mask;
+         unsigned int mask;
          png_size_t row_bytes = row_info->rowbytes;
 
          if (bit_depth->gray == 1 && row_info->bit_depth == 2)
@@ -301,20 +225,22 @@ png_do_shift(png_row_infop row_info, png_bytep row,
 
          for (i = 0; i < row_bytes; i++, bp++)
          {
-            png_uint_16 v;
             int j;
+            unsigned int v, out;
 
             v = *bp;
-            *bp = 0;
+            out = 0;
 
             for (j = shift_start[0]; j > -shift_dec[0]; j -= shift_dec[0])
             {
                if (j > 0)
-                  *bp |= (png_byte)((v << j) & 0xff);
+                  out |= v << j;
 
                else
-                  *bp |= (png_byte)((v >> (-j)) & mask);
+                  out |= (v >> (-j)) & mask;
             }
+
+            *bp = (png_byte)(out & 0xff);
          }
       }
 
@@ -327,21 +253,23 @@ png_do_shift(png_row_infop row_info, png_bytep row,
          for (i = 0; i < istop; i++, bp++)
          {
 
-            png_uint_16 v;
+            const unsigned int c = i%channels;
             int j;
-            int c = (int)(i%channels);
+            unsigned int v, out;
 
             v = *bp;
-            *bp = 0;
+            out = 0;
 
             for (j = shift_start[c]; j > -shift_dec[c]; j -= shift_dec[c])
             {
                if (j > 0)
-                  *bp |= (png_byte)((v << j) & 0xff);
+                  out |= v << j;
 
                else
-                  *bp |= (png_byte)((v >> (-j)) & 0xff);
+                  out |= v >> (-j);
             }
+
+            *bp = (png_byte)(out & 0xff);
          }
       }
 
@@ -353,22 +281,22 @@ png_do_shift(png_row_infop row_info, png_bytep row,
 
          for (bp = row, i = 0; i < istop; i++)
          {
-            int c = (int)(i%channels);
-            png_uint_16 value, v;
+            const unsigned int c = i%channels;
             int j;
+            unsigned int value, v;
 
-            v = (png_uint_16)(((png_uint_16)(*bp) << 8) + *(bp + 1));
+            v = png_get_uint_16(bp);
             value = 0;
 
             for (j = shift_start[c]; j > -shift_dec[c]; j -= shift_dec[c])
             {
                if (j > 0)
-                  value |= (png_uint_16)((v << j) & (png_uint_16)0xffff);
+                  value |= v << j;
 
                else
-                  value |= (png_uint_16)((v >> (-j)) & (png_uint_16)0xffff);
+                  value |= v >> (-j);
             }
-            *bp++ = (png_byte)(value >> 8);
+            *bp++ = (png_byte)((value >> 8) & 0xff);
             *bp++ = (png_byte)(value & 0xff);
          }
       }
@@ -377,7 +305,7 @@ png_do_shift(png_row_infop row_info, png_bytep row,
 #endif
 
 #ifdef PNG_WRITE_SWAP_ALPHA_SUPPORTED
-void /* PRIVATE */
+static void
 png_do_write_swap_alpha(png_row_infop row_info, png_bytep row)
 {
    png_debug(1, "in png_do_write_swap_alpha");
@@ -425,7 +353,7 @@ png_do_write_swap_alpha(png_row_infop row_info, png_bytep row)
                *(dp++) = save[1];
             }
          }
-#endif /* PNG_WRITE_16BIT_SUPPORTED */
+#endif /* WRITE_16BIT */
       }
 
       else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
@@ -464,14 +392,14 @@ png_do_write_swap_alpha(png_row_infop row_info, png_bytep row)
                *(dp++) = save[1];
             }
          }
-#endif /* PNG_WRITE_16BIT_SUPPORTED */
+#endif /* WRITE_16BIT */
       }
    }
 }
 #endif
 
 #ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED
-void /* PRIVATE */
+static void
 png_do_write_invert_alpha(png_row_infop row_info, png_bytep row)
 {
    png_debug(1, "in png_do_write_invert_alpha");
@@ -521,7 +449,7 @@ png_do_write_invert_alpha(png_row_infop row_info, png_bytep row)
                *(dp++) = (png_byte)(255 - *(sp++));
             }
          }
-#endif /* PNG_WRITE_16BIT_SUPPORTED */
+#endif /* WRITE_16BIT */
       }
 
       else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
@@ -559,75 +487,88 @@ png_do_write_invert_alpha(png_row_infop row_info, png_bytep row)
                *(dp++) = (png_byte)(255 - *(sp++));
             }
          }
-#endif /* PNG_WRITE_16BIT_SUPPORTED */
+#endif /* WRITE_16BIT */
       }
    }
 }
 #endif
-#endif /* PNG_WRITE_TRANSFORMS_SUPPORTED */
 
-#ifdef PNG_MNG_FEATURES_SUPPORTED
-/* Undoes intrapixel differencing  */
+/* Transform the data according to the user's wishes.  The order of
+ * transformations is significant.
+ */
 void /* PRIVATE */
-png_do_write_intrapixel(png_row_infop row_info, png_bytep row)
+png_do_write_transformations(png_structrp png_ptr, png_row_infop row_info)
 {
-   png_debug(1, "in png_do_write_intrapixel");
+   png_debug(1, "in png_do_write_transformations");
 
-   if ((row_info->color_type & PNG_COLOR_MASK_COLOR))
-   {
-      int bytes_per_pixel;
-      png_uint_32 row_width = row_info->width;
-      if (row_info->bit_depth == 8)
-      {
-         png_bytep rp;
-         png_uint_32 i;
+   if (png_ptr == NULL)
+      return;
 
-         if (row_info->color_type == PNG_COLOR_TYPE_RGB)
-            bytes_per_pixel = 3;
+#ifdef PNG_WRITE_USER_TRANSFORM_SUPPORTED
+   if ((png_ptr->transformations & PNG_USER_TRANSFORM) != 0)
+      if (png_ptr->write_user_transform_fn != NULL)
+         (*(png_ptr->write_user_transform_fn)) /* User write transform
+                                                 function */
+             (png_ptr,  /* png_ptr */
+             row_info,  /* row_info: */
+                /*  png_uint_32 width;       width of row */
+                /*  png_size_t 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) */
+             png_ptr->row_buf + 1);      /* start of pixel data for row */
+#endif
 
-         else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
-            bytes_per_pixel = 4;
+#ifdef PNG_WRITE_FILLER_SUPPORTED
+   if ((png_ptr->transformations & PNG_FILLER) != 0)
+      png_do_strip_channel(row_info, png_ptr->row_buf + 1,
+         !(png_ptr->flags & PNG_FLAG_FILLER_AFTER));
+#endif
 
-         else
-            return;
+#ifdef PNG_WRITE_PACKSWAP_SUPPORTED
+   if ((png_ptr->transformations & PNG_PACKSWAP) != 0)
+      png_do_packswap(row_info, png_ptr->row_buf + 1);
+#endif
 
-         for (i = 0, rp = row; i < row_width; i++, rp += bytes_per_pixel)
-         {
-            *(rp)     = (png_byte)((*rp       - *(rp + 1)) & 0xff);
-            *(rp + 2) = (png_byte)((*(rp + 2) - *(rp + 1)) & 0xff);
-         }
-      }
+#ifdef PNG_WRITE_PACK_SUPPORTED
+   if ((png_ptr->transformations & PNG_PACK) != 0)
+      png_do_pack(row_info, png_ptr->row_buf + 1,
+          (png_uint_32)png_ptr->bit_depth);
+#endif
 
-#ifdef PNG_WRITE_16BIT_SUPPORTED
-      else if (row_info->bit_depth == 16)
-      {
-         png_bytep rp;
-         png_uint_32 i;
+#ifdef PNG_WRITE_SWAP_SUPPORTED
+#  ifdef PNG_16BIT_SUPPORTED
+   if ((png_ptr->transformations & PNG_SWAP_BYTES) != 0)
+      png_do_swap(row_info, png_ptr->row_buf + 1);
+#  endif
+#endif
+
+#ifdef PNG_WRITE_SHIFT_SUPPORTED
+   if ((png_ptr->transformations & PNG_SHIFT) != 0)
+      png_do_shift(row_info, png_ptr->row_buf + 1,
+          &(png_ptr->shift));
+#endif
 
-         if (row_info->color_type == PNG_COLOR_TYPE_RGB)
-            bytes_per_pixel = 6;
+#ifdef PNG_WRITE_SWAP_ALPHA_SUPPORTED
+   if ((png_ptr->transformations & PNG_SWAP_ALPHA) != 0)
+      png_do_write_swap_alpha(row_info, png_ptr->row_buf + 1);
+#endif
 
-         else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
-            bytes_per_pixel = 8;
+#ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED
+   if ((png_ptr->transformations & PNG_INVERT_ALPHA) != 0)
+      png_do_write_invert_alpha(row_info, png_ptr->row_buf + 1);
+#endif
 
-         else
-            return;
+#ifdef PNG_WRITE_BGR_SUPPORTED
+   if ((png_ptr->transformations & PNG_BGR) != 0)
+      png_do_bgr(row_info, png_ptr->row_buf + 1);
+#endif
 
-         for (i = 0, rp = row; i < row_width; i++, rp += bytes_per_pixel)
-         {
-            png_uint_32 s0   = (*(rp    ) << 8) | *(rp + 1);
-            png_uint_32 s1   = (*(rp + 2) << 8) | *(rp + 3);
-            png_uint_32 s2   = (*(rp + 4) << 8) | *(rp + 5);
-            png_uint_32 red  = (png_uint_32)((s0 - s1) & 0xffffL);
-            png_uint_32 blue = (png_uint_32)((s2 - s1) & 0xffffL);
-            *(rp    ) = (png_byte)((red >> 8) & 0xff);
-            *(rp + 1) = (png_byte)(red & 0xff);
-            *(rp + 4) = (png_byte)((blue >> 8) & 0xff);
-            *(rp + 5) = (png_byte)(blue & 0xff);
-         }
-      }
-#endif /* PNG_WRITE_16BIT_SUPPORTED */
-   }
+#ifdef PNG_WRITE_INVERT_SUPPORTED
+   if ((png_ptr->transformations & PNG_INVERT_MONO) != 0)
+      png_do_invert(row_info, png_ptr->row_buf + 1);
+#endif
 }
-#endif /* PNG_MNG_FEATURES_SUPPORTED */
-#endif /* PNG_WRITE_SUPPORTED */
+#endif /* WRITE_TRANSFORMS */
+#endif /* WRITE */