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[devel] Improved gamma range checks and other things OpenWatcom warns about.

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This commit is contained in:
John Bowler
2011-06-11 06:42:06 -05:00
committed by Glenn Randers-Pehrson
parent b011fe1c12
commit d2f0bc2d13
5 changed files with 28 additions and 30 deletions
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29
png.c
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@@ -743,6 +743,13 @@ png_check_cHRM_fixed(png_structp png_ptr,
if (png_ptr == NULL)
return 0;
/* (x,y,z) values are first limited to 0..100000 (PNG_FP_1), the white
* y must also be greater than 0. To test for the upper limit calculate
* (PNG_FP_1-y) - x must be <= to this for z to be >= 0 (and the expression
* cannot overflow.) At this point we know x and y are >= 0 and (x+y) is
* <= PNG_FP_1. The previous test on PNG_MAX_UINT_31 is removed because it
* pointless (and it produces compiler warnings!)
*/
if (white_x < 0 || white_y <= 0 ||
red_x < 0 || red_y < 0 ||
green_x < 0 || green_y < 0 ||
@@ -752,38 +759,26 @@ png_check_cHRM_fixed(png_structp png_ptr,
"Ignoring attempt to set negative chromaticity value");
ret = 0;
}
if (white_x > (png_fixed_point)PNG_UINT_31_MAX ||
white_y > (png_fixed_point)PNG_UINT_31_MAX ||
red_x > (png_fixed_point)PNG_UINT_31_MAX ||
red_y > (png_fixed_point)PNG_UINT_31_MAX ||
green_x > (png_fixed_point)PNG_UINT_31_MAX ||
green_y > (png_fixed_point)PNG_UINT_31_MAX ||
blue_x > (png_fixed_point)PNG_UINT_31_MAX ||
blue_y > (png_fixed_point)PNG_UINT_31_MAX )
{
png_warning(png_ptr,
"Ignoring attempt to set chromaticity value exceeding 21474.83");
ret = 0;
}
if (white_x > 100000L - white_y)
/* And (x+y) must be <= PNG_FP_1 (so z is >= 0) */
if (white_x > PNG_FP_1 - white_y)
{
png_warning(png_ptr, "Invalid cHRM white point");
ret = 0;
}
if (red_x > 100000L - red_y)
if (red_x > PNG_FP_1 - red_y)
{
png_warning(png_ptr, "Invalid cHRM red point");
ret = 0;
}
if (green_x > 100000L - green_y)
if (green_x > PNG_FP_1 - green_y)
{
png_warning(png_ptr, "Invalid cHRM green point");
ret = 0;
}
if (blue_x > 100000L - blue_y)
if (blue_x > PNG_FP_1 - blue_y)
{
png_warning(png_ptr, "Invalid cHRM blue point");
ret = 0;