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Fixed bug #855 Ludwig Nussel 2009-10-18 06:31:52 PDT an mprotect call was added to fix bug 528. However that results in a buffer that allows writing and code execution. Ie the no-execute security features of modern operating systems are defeated this way. Two mprotect calls are needed. One to make the buffer executable but not writeable when done and another one to make the buffer writeable again if the content needs to be changed.
author Sam Lantinga <slouken@libsdl.org>
date Sun, 18 Oct 2009 17:31:37 +0000
parents 355632dca928
children
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<HTML
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>SDL_SetGammaRamp</TITLE
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><H1
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>SDL_SetGammaRamp</H1
><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN1624"
></A
><H2
>Name</H2
>SDL_SetGammaRamp&nbsp;--&nbsp;Sets the color gamma lookup tables for the display</DIV
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><H2
>Synopsis</H2
><DIV
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><P
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><PRE
CLASS="FUNCSYNOPSISINFO"
>#include "SDL.h"</PRE
><P
><CODE
><CODE
CLASS="FUNCDEF"
>int <B
CLASS="FSFUNC"
>SDL_SetGammaRamp</B
></CODE
>(Uint16 *redtable, Uint16 *greentable, Uint16 *bluetable);</CODE
></P
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><A
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><H2
>Description</H2
><P
>Sets the gamma lookup tables for the display for each color component.
Each table is an array of 256 Uint16 values, representing a mapping
between the input and output for that channel. The input is the index
into the array, and the output is the 16-bit gamma value at that index,
scaled to the output color precision. You may pass NULL to any of the
channels to leave them unchanged.</P
><P
>This function adjusts the gamma based on lookup tables, you can also
have the gamma calculated based on a "gamma function" parameter with
<A
HREF="sdlsetgamma.html"
>SDL_SetGamma</A
>.</P
><P
>Not all display hardware is able to change gamma.</P
></DIV
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><H2
>Return Value</H2
><P
>Returns -1 on error (or if gamma adjustment is not supported).</P
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></A
><H2
>See Also</H2
><P
><A
HREF="sdlsetgamma.html"
>SDL_SetGamma</A
>
<A
HREF="sdlgetgammaramp.html"
>SDL_GetGammaRamp</A
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