/*
SDL - Simple DirectMedia Layer
Copyright (C) 1997-2004 Sam Lantinga
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public
License as published by the Free Software Foundation; either
version 2 of the License, or (at your option) any later version.
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with this library; if not, write to the Free
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
Sam Lantinga
slouken@libsdl.org
*/
#ifdef SAVE_RCSID
static char rcsid =
"@(#) $Id: SDL_rwops.c,v 1.9 2005/06/24 12:48:38 icculus Exp $";
#endif
/* This file provides a general interface for SDL to read and write
data sources.  It can easily be extended to files, memory, etc.
*/
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include "SDL_error.h"
#include "SDL_rwops.h"
/* Functions to read/write stdio file pointers */
static int stdio_seek(SDL_RWops *context, int offset, int whence)
{
_10000:if (!( fseek(context->hidden.stdio.fp, offset, whence) == 0 )) goto _10030;
_10010:return(ftell(context->hidden.stdio.fp));
_10020:goto _10050;
_10030:SDL_Error(SDL_EFSEEK);
_10040:return(-1);
_10050:0;
}
static int stdio_read(SDL_RWops *context, void *ptr, int size, int maxnum)
{
size_t nread;
_10060:nread = fread(ptr, size, maxnum, context->hidden.stdio.fp); 
_10070:if (!( nread == 0 && ferror(context->hidden.stdio.fp) )) goto _10090;
_10080:SDL_Error(SDL_EFREAD);
_10090:return(nread);
}
static int stdio_write(SDL_RWops *context, const void *ptr, int size, int num)
{
size_t nwrote;
_10100:nwrote = fwrite(ptr, size, num, context->hidden.stdio.fp);
_10110:if (!( nwrote == 0 && ferror(context->hidden.stdio.fp) )) goto _10130;
_10120:SDL_Error(SDL_EFWRITE);
_10130:return(nwrote);
}
static int stdio_close(SDL_RWops *context)
{
_10140:if (!( context )) goto _10180;
_10150:if (!( context->hidden.stdio.autoclose )) goto _10170;
/* WARNING:  Check the return value here! */
_10160:fclose(context->hidden.stdio.fp);
_10170:free(context);
_10180:return(0);
}
/* Functions to read/write memory pointers */
static int mem_seek(SDL_RWops *context, int offset, int whence)
{
Uint8 *newpos;
_10190:switch (whence) {
case SEEK_SET:
_10200:newpos = context->hidden.mem.base+offset;
_10210:break;
case SEEK_CUR:
_10220:newpos = context->hidden.mem.here+offset;
_10230:break;
case SEEK_END:
_10240:newpos = context->hidden.mem.stop+offset;
_10250:break;
_10260:default:
SDL_SetError("Unknown value for 'whence'");
_10270:return(-1);
}
_10280:if (!( newpos < context->hidden.mem.base )) goto _10300;
_10290:newpos = context->hidden.mem.base;
_10300:if (!( newpos > context->hidden.mem.stop )) goto _10320;
_10310:newpos = context->hidden.mem.stop;
_10320:context->hidden.mem.here = newpos;
_10330:return(context->hidden.mem.here-context->hidden.mem.base);
}
static int mem_read(SDL_RWops *context, void *ptr, int size, int maxnum)
{
int total_bytes;
int mem_available;
_10340:total_bytes = (maxnum * size);
_10350:if (!( (maxnum <= 0) || (size <= 0) || ((total_bytes / maxnum) != size) )) goto _10370;
_10360:return 0;
_10370:mem_available = (context->hidden.mem.stop - context->hidden.mem.here);
_10380:if (!(total_bytes > mem_available)) goto _10400;
_10390:total_bytes = mem_available;
_10400:memcpy(ptr, context->hidden.mem.here, total_bytes);
_10410:context->hidden.mem.here += total_bytes;
_10420:return (total_bytes / size);
}
static int mem_write(SDL_RWops *context, const void *ptr, int size, int num)
{
_10430:if (!( (context->hidden.mem.here + (num*size)) > context->hidden.mem.stop )) goto _10450;
_10440:num = (context->hidden.mem.stop-context->hidden.mem.here)/size;
_10450:memcpy(context->hidden.mem.here, ptr, num*size);
_10460:context->hidden.mem.here += num*size;
_10470:return(num);
}
static int mem_writeconst(SDL_RWops *context, const void *ptr, int size, int num)
{
_10480:SDL_SetError("Can't write to read-only memory");
_10490:return(-1);
}
static int mem_close(SDL_RWops *context)
{
_10500:if (!( context )) goto _10520;
_10510:free(context);
_10520:return(0);
}
/* Functions to create SDL_RWops structures from various data sources */
#ifdef WIN32
/* Aggh.  You can't (apparently) open a file in an application and
read from it in a DLL.
*/
static int in_sdl = 0;
#endif
#ifdef macintosh
/*
* translate unix-style slash-separated filename to mac-style colon-separated
* name; return malloced string
*/
static char *unix_to_mac(const char *file)
{
int flen = strlen(file);
char *path = malloc(flen + 2);
const char *src = file;
char *dst = path;
_10530:if (!(*src == '/')) goto _10560;
/* really depends on filesystem layout, hope for the best */
_10540:src++;
_10550:goto _10580;
/* Check if this is a MacOS path to begin with */
_10560:if(*src != ':')
_10570:*dst++ = ':';   /* relative paths begin with ':' */
_10580:if (!(src < file + flen)) goto _10720;
const char *end = strchr(src, '/');
int len;
_10590:if(!end)
_10600:end = file + flen; /* last component */
_10610:len = end - src;
_10620:if (!(len == 0 || (len == 1 && src[0] == '.'))) goto _10640;
/* remove repeated slashes and . */
_10630:goto _10700;
_10640:if (!(len == 2 && src[0] == '.' && src[1] == '.')) goto _10660;
/* replace .. with the empty string */
_10650:goto _10680;
_10660:memcpy(dst, src, len);
_10670:dst += len;
_10680:if(end < file + flen)
_10690:*dst++ = ':';
_10700:src = end + 1;
_10710:goto _10580;
_10720:*dst++ = '\0';
_10730:return path;
}
#endif /* macintosh */
SDL_RWops *SDL_RWFromFile(const char *file, const char *mode)
{
FILE *fp;
SDL_RWops *rwops;
_10740:rwops = NULL;
#ifdef macintosh
{
char *mpath = unix_to_mac(file);
_10750:fp = fopen(mpath, mode);
_10760:free(mpath);
}
#else
_10770:fp = fopen(file, mode);
#endif
_10780:if ( fp == NULL ) {
_10790:SDL_SetError("Couldn't open %s", file);
} else {
#ifdef WIN32
_10800:in_sdl = 1;
_10810:rwops = SDL_RWFromFP(fp, 1);
_10820:in_sdl = 0;
#else
_10830:rwops = SDL_RWFromFP(fp, 1);
#endif
}
_10840:return(rwops);
}
SDL_RWops *SDL_RWFromFP(FILE *fp, int autoclose)
{
SDL_RWops *rwops;
#ifdef WIN32
_10850:if ( ! in_sdl ) {
_10860:SDL_SetError("You can't pass a FILE pointer to a DLL (?)");
/*return(NULL);*/
}
#endif
_10870:rwops = SDL_AllocRW();
_10880:if (!( rwops != NULL )) goto _10950;
_10890:rwops->seek = stdio_seek;
_10900:rwops->read = stdio_read;
_10910:rwops->write = stdio_write;
_10920:rwops->close = stdio_close;
_10930:rwops->hidden.stdio.fp = fp;
_10940:rwops->hidden.stdio.autoclose = autoclose;
_10950:return(rwops);
}
SDL_RWops *SDL_RWFromMem(void *mem, int size)
{
SDL_RWops *rwops;
_10960:rwops = SDL_AllocRW();
_10970:if (!( rwops != NULL )) goto _11050;
_10980:rwops->seek = mem_seek;
_10990:rwops->read = mem_read;
_11000:rwops->write = mem_write;
_11010:rwops->close = mem_close;
_11020:rwops->hidden.mem.base = (Uint8 *)mem;
_11030:rwops->hidden.mem.here = rwops->hidden.mem.base;
_11040:rwops->hidden.mem.stop = rwops->hidden.mem.base+size;
_11050:return(rwops);
}
SDL_RWops *SDL_RWFromConstMem(const void *mem, int size)
{
SDL_RWops *rwops;
_11060:rwops = SDL_AllocRW();
_11070:if (!( rwops != NULL )) goto _11150;
_11080:rwops->seek = mem_seek;
_11090:rwops->read = mem_read;
_11100:rwops->write = mem_writeconst;
_11110:rwops->close = mem_close;
_11120:rwops->hidden.mem.base = (Uint8 *)mem;
_11130:rwops->hidden.mem.here = rwops->hidden.mem.base;
_11140:rwops->hidden.mem.stop = rwops->hidden.mem.base+size;
_11150:return(rwops);
}
SDL_RWops *SDL_AllocRW(void)
{
SDL_RWops *area;
_11160:area = (SDL_RWops *)malloc(sizeof *area);
_11170:if (!( area == NULL )) goto _11190;
_11180:SDL_OutOfMemory();
_11190:return(area);
}
void SDL_FreeRW(SDL_RWops *area)
{
_11200:free(area);
}