--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/file/SDL_rwops.c	Thu Apr 26 16:45:43 2001 +0000
@@ -0,0 +1,274 @@
+/*
+    SDL - Simple DirectMedia Layer
+    Copyright (C) 1997, 1998, 1999, 2000, 2001  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@devolution.com
+*/
+
+#ifdef SAVE_RCSID
+static char rcsid =
+ "@(#) $Id$";
+#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 <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)
+{
+	if ( fseek(context->hidden.stdio.fp, offset, whence) == 0 ) {
+		return(ftell(context->hidden.stdio.fp));
+	} else {
+		SDL_Error(SDL_EFSEEK);
+		return(-1);
+	}
+}
+static int stdio_read(SDL_RWops *context, void *ptr, int size, int maxnum)
+{
+	size_t nread;
+
+	nread = fread(ptr, size, maxnum, context->hidden.stdio.fp); 
+	if ( nread == 0 && ferror(context->hidden.stdio.fp) ) {
+		SDL_Error(SDL_EFREAD);
+	}
+	return(nread);
+}
+static int stdio_write(SDL_RWops *context, const void *ptr, int size, int num)
+{
+	size_t nwrote;
+
+	nwrote = fwrite(ptr, size, num, context->hidden.stdio.fp);
+	if ( nwrote == 0 && ferror(context->hidden.stdio.fp) ) {
+		SDL_Error(SDL_EFWRITE);
+	}
+	return(nwrote);
+}
+static int stdio_close(SDL_RWops *context)
+{
+	if ( context ) {
+		if ( context->hidden.stdio.autoclose ) {
+			/* WARNING:  Check the return value here! */
+			fclose(context->hidden.stdio.fp);
+		}
+		free(context);
+	}
+	return(0);
+}
+
+/* Functions to read/write memory pointers */
+
+static int mem_seek(SDL_RWops *context, int offset, int whence)
+{
+	Uint8 *newpos;
+
+	switch (whence) {
+		case SEEK_SET:
+			newpos = context->hidden.mem.base+offset;
+			break;
+		case SEEK_CUR:
+			newpos = context->hidden.mem.here+offset;
+			break;
+		case SEEK_END:
+			newpos = context->hidden.mem.stop+offset;
+			break;
+		default:
+			SDL_SetError("Unknown value for 'whence'");
+			return(-1);
+	}
+	if ( newpos < context->hidden.mem.base ) {
+		newpos = context->hidden.mem.base;
+	}
+	if ( newpos > context->hidden.mem.stop ) {
+		newpos = context->hidden.mem.stop;
+	}
+	context->hidden.mem.here = newpos;
+	return(context->hidden.mem.here-context->hidden.mem.base);
+}
+static int mem_read(SDL_RWops *context, void *ptr, int size, int maxnum)
+{
+	int num;
+
+	num = maxnum;
+	if ( (context->hidden.mem.here + (num*size)) > context->hidden.mem.stop ) {
+		num = (context->hidden.mem.stop-context->hidden.mem.here)/size;
+	}
+	memcpy(ptr, context->hidden.mem.here, num*size);
+	context->hidden.mem.here += num*size;
+	return(num);
+}
+static int mem_write(SDL_RWops *context, const void *ptr, int size, int num)
+{
+	if ( (context->hidden.mem.here + (num*size)) > context->hidden.mem.stop ) {
+		num = (context->hidden.mem.stop-context->hidden.mem.here)/size;
+	}
+	memcpy(context->hidden.mem.here, ptr, num*size);
+	context->hidden.mem.here += num*size;
+	return(num);
+}
+static int mem_close(SDL_RWops *context)
+{
+	if ( context ) {
+		free(context);
+	}
+	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;
+	if(*src == '/') {
+		/* really depends on filesystem layout, hope for the best */
+		src++;
+	} else {
+		/* Check if this is a MacOS path to begin with */
+		if(*src != ':')
+			*dst++ = ':';   /* relative paths begin with ':' */
+	}
+	while(src < file + flen) {
+		const char *end = strchr(src, '/');
+		int len;
+		if(!end)
+			end = file + flen; /* last component */
+		len = end - src;
+		if(len == 0 || (len == 1 && src[0] == '.')) {
+			/* remove repeated slashes and . */
+		} else {
+			if(len == 2 && src[0] == '.' && src[1] == '.') {
+				/* replace .. with the empty string */
+			} else {
+				memcpy(dst, src, len);
+				dst += len;
+			}
+			if(end < file + flen)
+				*dst++ = ':';
+		}
+		src = end + 1;
+	}
+	*dst++ = '\0';
+	return path;
+}
+#endif /* macintosh */
+
+SDL_RWops *SDL_RWFromFile(const char *file, const char *mode)
+{
+	FILE *fp;
+	SDL_RWops *rwops;
+
+	rwops = NULL;
+
+#ifdef macintosh
+	{
+		char *mpath = unix_to_mac(file);
+		fp = fopen(mpath, mode);
+		free(mpath);
+	}
+#else
+	fp = fopen(file, mode);
+#endif
+	if ( fp == NULL ) {
+		SDL_SetError("Couldn't open %s", file);
+	} else {
+#ifdef WIN32
+		in_sdl = 1;
+		rwops = SDL_RWFromFP(fp, 1);
+		in_sdl = 0;
+#else
+		rwops = SDL_RWFromFP(fp, 1);
+#endif
+	}
+	return(rwops);
+}
+
+SDL_RWops *SDL_RWFromFP(FILE *fp, int autoclose)
+{
+	SDL_RWops *rwops;
+
+#ifdef WIN32
+	if ( ! in_sdl ) {
+		SDL_SetError("You can't pass a FILE pointer to a DLL (??)");
+		/*return(NULL);*/
+	}
+#endif
+	rwops = SDL_AllocRW();
+	if ( rwops != NULL ) {
+		rwops->seek = stdio_seek;
+		rwops->read = stdio_read;
+		rwops->write = stdio_write;
+		rwops->close = stdio_close;
+		rwops->hidden.stdio.fp = fp;
+		rwops->hidden.stdio.autoclose = autoclose;
+	}
+	return(rwops);
+}
+
+SDL_RWops *SDL_RWFromMem(void *mem, int size)
+{
+	SDL_RWops *rwops;
+
+	rwops = SDL_AllocRW();
+	if ( rwops != NULL ) {
+		rwops->seek = mem_seek;
+		rwops->read = mem_read;
+		rwops->write = mem_write;
+		rwops->close = mem_close;
+		rwops->hidden.mem.base = (Uint8 *)mem;
+		rwops->hidden.mem.here = rwops->hidden.mem.base;
+		rwops->hidden.mem.stop = rwops->hidden.mem.base+size;
+	}
+	return(rwops);
+}
+
+SDL_RWops *SDL_AllocRW(void)
+{
+	SDL_RWops *area;
+
+	area = (SDL_RWops *)malloc(sizeof *area);
+	if ( area == NULL ) {
+		SDL_OutOfMemory();
+	}
+	return(area);
+}
+
+void SDL_FreeRW(SDL_RWops *area)
+{
+	free(area);
+}