view docs/man3/SDL_GL_GetProcAddress.3 @ 4388:1524d3237820 SDL-1.2

Fixed bug #896 John Popplewell 2009-12-08 23:05:50 PST Originally reported by AKFoerster on the mailing list. Error decoding UTF8 Russian text to UTF-16LE on Windows, but specifically on platforms without iconv support (the default on Windows). Valid UTF8 characters are flagged as being overlong and then substituted by the UNKNOWN_UNICODE character. After studying the testiconv.c example program, reading the RFCs and putting some printf statements in SDL_iconv.c the problem is in a test for 'Maximum overlong sequences', specifically 4.2.1, which is carried out by the following code: } else if ( p[0] >= 0xC0 ) { if ( (p[0] & 0xE0) != 0xC0 ) { /* Skip illegal sequences return SDL_ICONV_EILSEQ; */ ch = UNKNOWN_UNICODE; } else { if ( (p[0] & 0xCE) == 0xC0 ) { <<<<<<<< here overlong = SDL_TRUE; } ch = (Uint32)(p[0] & 0x1F); left = 1; } } else { Here is the 2-byte encoding of a character in range 00000080 - 000007FF 110xxxxx 10xxxxxx The line in question is supposed to be checking for an overlong sequence which would be less than 11000001 10111111 which should be represented as a single byte. BUT, the mask value (0xCE) is wrong, it isn't checking the top-most bit: 11000001 value 11001110 mask (incorrect) ^ and should be (0xDE): 11000001 value 11011110 mask (correct) making the above code: } else if ( p[0] >= 0xC0 ) { if ( (p[0] & 0xE0) != 0xC0 ) { /* Skip illegal sequences return SDL_ICONV_EILSEQ; */ ch = UNKNOWN_UNICODE; } else { if ( (p[0] & 0xDE) == 0xC0 ) { <<<<<<<< here overlong = SDL_TRUE; } ch = (Uint32)(p[0] & 0x1F); left = 1; } } else { I can supply a test program and/or a patch if required, best regards, John Popplewell
author Sam Lantinga <slouken@libsdl.org>
date Fri, 11 Dec 2009 08:00:57 +0000
parents 1238da4a7112
children
line wrap: on
line source

.TH "SDL_GL_GetProcAddress" "3" "Tue 11 Sep 2001, 23:01" "SDL" "SDL API Reference" 
.SH "NAME"
SDL_GL_GetProcAddress \- Get the address of a GL function
.SH "SYNOPSIS"
.PP
\fB#include "SDL\&.h"
.sp
\fBvoid *\fBSDL_GL_GetProcAddress\fP\fR(\fBconst char* proc\fR);
.SH "DESCRIPTION"
.PP
Returns the address of the GL function \fBproc\fR, or \fBNULL\fR if the function is not found\&. If the GL library is loaded at runtime, with \fI\fBSDL_GL_LoadLibrary\fP\fR, then \fIall\fP GL functions must be retrieved this way\&. Usually this is used to retrieve function pointers to OpenGL extensions\&.
.SH "EXAMPLE"
.PP
.nf
\f(CWtypedef void (*GL_ActiveTextureARB_Func)(unsigned int);
GL_ActiveTextureARB_Func glActiveTextureARB_ptr = 0;
int has_multitexture=1;
\&.
\&.
\&.
/* Get function pointer */
glActiveTextureARB_ptr=(GL_ActiveTextureARB_Func) SDL_GL_GetProcAddress("glActiveTextureARB");

/* Check for a valid function ptr */
if(!glActiveTextureARB_ptr){
  fprintf(stderr, "Multitexture Extensions not present\&.
");
  has_multitexture=0;
}
\&.
\&.
\&.
\&.
if(has_multitexture){
  glActiveTextureARB_ptr(GL_TEXTURE0_ARB);
  \&.
  \&.
}
else{
  \&.
  \&.
}\fR
.fi
.PP
.SH "SEE ALSO"
.PP
\fI\fBSDL_GL_LoadLibrary\fP\fR
.\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:01