include/SDL_rwops.h
changeset 0 74212992fb08
child 251 b8688cfdc232
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/include/SDL_rwops.h	Thu Apr 26 16:45:43 2001 +0000
@@ -0,0 +1,113 @@
+/*
+    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.
+*/
+
+#ifndef _SDL_RWops_h
+#define _SDL_RWops_h
+
+#include <stdio.h>
+
+#include "SDL_types.h"
+
+#include "begin_code.h"
+/* Set up for C function definitions, even when using C++ */
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* This is the read/write operation structure -- very basic */
+
+typedef struct SDL_RWops {
+	/* Seek to 'offset' relative to whence, one of stdio's whence values:
+		SEEK_SET, SEEK_CUR, SEEK_END
+	   Returns the final offset in the data source.
+	 */
+	int (*seek)(struct SDL_RWops *context, int offset, int whence);
+
+	/* Read up to 'num' objects each of size 'objsize' from the data
+	   source to the area pointed at by 'ptr'.
+	   Returns the number of objects read, or -1 if the read failed.
+	 */
+	int (*read)(struct SDL_RWops *context, void *ptr, int size, int maxnum);
+
+	/* Write exactly 'num' objects each of size 'objsize' from the area
+	   pointed at by 'ptr' to data source.
+	   Returns 'num', or -1 if the write failed.
+	 */
+	int (*write)(struct SDL_RWops *context, const void *ptr, int size, int num);
+
+	/* Close and free an allocated SDL_FSops structure */
+	int (*close)(struct SDL_RWops *context);
+
+	Uint32 type;
+	union {
+	    struct {
+		int autoclose;
+	 	FILE *fp;
+	    } stdio;
+	    struct {
+		Uint8 *base;
+	 	Uint8 *here;
+		Uint8 *stop;
+	    } mem;
+	    struct {
+		void *data1;
+	    } unknown;
+	} hidden;
+
+} SDL_RWops;
+
+
+/* Functions to create SDL_RWops structures from various data sources */
+
+extern DECLSPEC SDL_RWops * SDL_RWFromFile(const char *file, const char *mode);
+
+extern DECLSPEC SDL_RWops * SDL_RWFromFP(FILE *fp, int autoclose);
+
+extern DECLSPEC SDL_RWops * SDL_RWFromMem(void *mem, int size);
+
+extern DECLSPEC SDL_RWops * SDL_AllocRW(void);
+extern DECLSPEC void SDL_FreeRW(SDL_RWops *area);
+
+/* Macros to easily read and write from an SDL_RWops structure */
+#define SDL_RWseek(ctx, offset, whence)	(ctx)->seek(ctx, offset, whence)
+#define SDL_RWtell(ctx)			(ctx)->seek(ctx, 0, SEEK_CUR)
+#define SDL_RWread(ctx, ptr, size, n)	(ctx)->read(ctx, ptr, size, n)
+#define SDL_RWwrite(ctx, ptr, size, n)	(ctx)->write(ctx, ptr, size, n)
+#define SDL_RWclose(ctx)		(ctx)->close(ctx)
+
+
+/* Ends C function definitions when using C++ */
+#ifdef __cplusplus
+}
+#endif
+#include "close_code.h"
+
+#endif /* _SDL_RWops_h */