view docs/html/sdlpalette.html @ 4355:9b464226e541 SDL-1.2

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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>SDL_Palette</TITLE
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><H1
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>SDL_Palette</H1
><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN3129"
></A
><H2
>Name</H2
>SDL_Palette&nbsp;--&nbsp;Color palette for 8-bit pixel formats</DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN3132"
></A
><H2
>Structure Definition</H2
><PRE
CLASS="PROGRAMLISTING"
>typedef struct{
  int ncolors;
  SDL_Color *colors;
} SDL_Palette;</PRE
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><H2
>Structure Data</H2
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><TT
CLASS="STRUCTFIELD"
><I
>ncolors</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Number of colors used in this palette</TD
></TR
><TR
><TD
ALIGN="LEFT"
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><TT
CLASS="STRUCTFIELD"
><I
>colors</I
></TT
></TD
><TD
ALIGN="LEFT"
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>Pointer to <A
HREF="sdlcolor.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_Color</SPAN
></A
> structures that make up the palette.</TD
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><H2
>Description</H2
><P
>Each pixel in an 8-bit surface is an index into the <TT
CLASS="STRUCTFIELD"
><I
>colors</I
></TT
> field of the <SPAN
CLASS="STRUCTNAME"
>SDL_Palette</SPAN
> structure store in <A
HREF="sdlpixelformat.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_PixelFormat</SPAN
></A
>. A <SPAN
CLASS="STRUCTNAME"
>SDL_Palette</SPAN
> should never need to be created manually. It is automatically created when SDL allocates a <SPAN
CLASS="STRUCTNAME"
>SDL_PixelFormat</SPAN
> for a surface. The colors values of a <A
HREF="sdlsurface.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_Surface</SPAN
></A
>s palette can be set with the <A
HREF="sdlsetcolors.html"
><TT
CLASS="FUNCTION"
>SDL_SetColors</TT
></A
>.</P
></DIV
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><A
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><H2
>See Also</H2
><P
><A
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><SPAN
CLASS="STRUCTNAME"
>SDL_Color</SPAN
></A
>,
<A
HREF="sdlsurface.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_Surface</SPAN
></A
>,
<A
HREF="sdlsetcolors.html"
><TT
CLASS="FUNCTION"
>SDL_SetColors</TT
></A
>
<A
HREF="sdlsetpalette.html"
><TT
CLASS="FUNCTION"
>SDL_SetPalette</TT
></A
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