[master] Changes to remove gcc warnings (John Bowler)
diff --git a/ANNOUNCE b/ANNOUNCE
index e1b7523..2145c37 100644
--- a/ANNOUNCE
+++ b/ANNOUNCE
@@ -61,6 +61,14 @@
is not defined).
Make the "png_get_uint_16" macro return a png_uint_32 in libpng-1.4 for API
compatibility.
+ Changes to remove gcc warnings (John Bowler)
+ Certain optional gcc warning flags resulted in warnings in libpng code.
+ With these changes only -Wconversion and -Wcast-qual cannot be turned on.
+ Changes are trivial rearrangements of code. -Wconversion is not possible
+ for pngrutil.c (because of the widespread use of += et al on variables
+ smaller than (int) or (unsigned int)) and -Wcast-qual is not possible
+ with pngwio.c and pngwutil.c because the 'write' callback and zlib
+ compression both fail to declare their input buffers with 'const'.
Send comments/corrections/commendations to glennrp at users.sourceforge.net
or to png-mng-implement at lists.sf.net (subscription required; visit
diff --git a/CHANGES b/CHANGES
index f81a9c6..4368e12 100644
--- a/CHANGES
+++ b/CHANGES
@@ -2713,6 +2713,14 @@
is not defined).
Make the "png_get_uint_16" macro return a png_uint_32 in libpng-1.4 for API
compatibility.
+ Changes to remove gcc warnings (John Bowler)
+ Certain optional gcc warning flags resulted in warnings in libpng code.
+ With these changes only -Wconversion and -Wcast-qual cannot be turned on.
+ Changes are trivial rearrangements of code. -Wconversion is not possible
+ for pngrutil.c (because of the widespread use of += et al on variables
+ smaller than (int) or (unsigned int)) and -Wcast-qual is not possible
+ with pngwio.c and pngwutil.c because the 'write' callback and zlib
+ compression both fail to declare their input buffers with 'const'.
Send comments/corrections/commendations to glennrp at users.sourceforge.net
or to png-mng-implement at lists.sf.net (subscription required; visit
diff --git a/pngpread.c b/pngpread.c
index e33b428..d735989 100644
--- a/pngpread.c
+++ b/pngpread.c
@@ -1109,6 +1109,8 @@
break;
}
+
+ default:
case 6:
{
png_push_have_row(png_ptr, png_ptr->row_buf + 1);
diff --git a/pngread.c b/pngread.c
index f1c0dc8..b3d13e4 100644
--- a/pngread.c
+++ b/pngread.c
@@ -1,7 +1,7 @@
/* pngread.c - read a PNG file
*
- * Last changed in libpng 1.4.5 [November 20, 2010]
+ * Last changed in libpng 1.4.5 [November 21, 2010]
* Copyright (c) 1998-2010 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.)
@@ -502,6 +502,7 @@
return;
}
break;
+
case 1:
if ((png_ptr->row_number & 0x07) || png_ptr->width < 5)
{
@@ -512,6 +513,7 @@
return;
}
break;
+
case 2:
if ((png_ptr->row_number & 0x07) != 4)
{
@@ -522,6 +524,7 @@
return;
}
break;
+
case 3:
if ((png_ptr->row_number & 3) || png_ptr->width < 3)
{
@@ -532,6 +535,7 @@
return;
}
break;
+
case 4:
if ((png_ptr->row_number & 3) != 2)
{
@@ -542,6 +546,7 @@
return;
}
break;
+
case 5:
if ((png_ptr->row_number & 1) || png_ptr->width < 2)
{
@@ -552,6 +557,8 @@
return;
}
break;
+
+ default:
case 6:
if (!(png_ptr->row_number & 1))
{
diff --git a/pngrtran.c b/pngrtran.c
index e8d9a99..703a8c9 100644
--- a/pngrtran.c
+++ b/pngrtran.c
@@ -1,7 +1,7 @@
/* pngrtran.c - transforms the data in a row for PNG readers
*
- * Last changed in libpng 1.4.5 [November 20, 2010]
+ * Last changed in libpng 1.4.5 [November 21, 2010]
* Copyright (c) 1998-2010 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.)
@@ -686,6 +686,11 @@
break;
case 3: png_ptr->transformations |= PNG_RGB_TO_GRAY_ERR;
+ break;
+
+ default:
+ png_error(png_ptr, "invalid error action in png_set_rgb_to_gray");
+ break;
}
if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
#ifdef PNG_READ_EXPAND_SUPPORTED
@@ -828,6 +833,8 @@
}
break;
+ default:
+
case 8:
case 16:
@@ -1028,6 +1035,9 @@
gs = 1.0 / (png_ptr->background_gamma *
png_ptr->screen_gamma);
break;
+
+ default:
+ png_error(png_ptr, "invalid background gamma type");
}
png_ptr->background_1.gray = (png_uint_16)(pow(
@@ -1626,6 +1636,9 @@
}
break;
}
+
+ default:
+ break;
}
row_info->bit_depth = 8;
row_info->pixel_depth = (png_byte)(8 * row_info->channels);
@@ -1682,6 +1695,9 @@
switch (row_info->bit_depth)
{
+ default:
+ break;
+
case 2:
{
png_bytep bp;
@@ -2798,6 +2814,9 @@
}
break;
}
+
+ default:
+ break;
}
break;
}
@@ -3230,6 +3249,9 @@
}
break;
}
+
+ default:
+ break;
}
if (row_info->color_type & PNG_COLOR_MASK_ALPHA)
@@ -3428,6 +3450,9 @@
}
break;
}
+
+ default:
+ break;
}
}
}
@@ -3522,6 +3547,9 @@
}
break;
}
+
+ default:
+ break;
}
row_info->bit_depth = 8;
row_info->pixel_depth = 8;
@@ -3672,6 +3700,9 @@
}
break;
}
+
+ default:
+ break;
}
row_info->bit_depth = 8;
diff --git a/pngrutil.c b/pngrutil.c
index 3ef330e..e979d24 100644
--- a/pngrutil.c
+++ b/pngrutil.c
@@ -68,6 +68,11 @@
png_uint_16 (PNGAPI
png_get_uint_16) (png_bytep buf)
{
+ /* ANSI-C requires an int value to accomodate at least 16 bits so this
+ * works and allows the compiler not to worry about possible narrowing
+ * on 32 bit systems. (Pre-ANSI systems did not make integers smaller
+ * than 16 bits either.)
+ */
unsigned int val =
((unsigned int)(*buf) << 8) +
((unsigned int)(*(buf + 1)));
diff --git a/pngwtran.c b/pngwtran.c
index 070caa5..2925a93 100644
--- a/pngwtran.c
+++ b/pngwtran.c
@@ -195,6 +195,9 @@
*dp = (png_byte)v;
break;
}
+
+ default:
+ break;
}
row_info->bit_depth = (png_byte)bit_depth;
row_info->pixel_depth = (png_byte)(bit_depth * row_info->channels);
diff --git a/pngwutil.c b/pngwutil.c
index 19feb1d..8f7c7c2 100644
--- a/pngwutil.c
+++ b/pngwutil.c
@@ -246,10 +246,12 @@
*/
/* Set up the compression buffers */
+ /* TODO: the following cast hides a potential overflow problem. */
png_ptr->zstream.avail_in = (uInt)text_len;
+ /* NOTE: assume zlib doesn't overwrite the input */
png_ptr->zstream.next_in = (Bytef *)text;
- png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
- png_ptr->zstream.next_out = (Bytef *)png_ptr->zbuf;
+ png_ptr->zstream.avail_out = png_ptr->zbuf_size;
+ png_ptr->zstream.next_out = png_ptr->zbuf;
/* This is the same compression loop as in png_write_row() */
do
