misc/libphyslayer/physfsrwops.c
branchphysfslayer
changeset 8524 a65e9bcf0a03
parent 8522 1853628ae285
child 9309 7e8f91634f80
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/misc/libphyslayer/physfsrwops.c	Fri Feb 22 05:43:56 2013 +0100
@@ -0,0 +1,219 @@
+/*
+ * This code provides a glue layer between PhysicsFS and Simple Directmedia
+ *  Layer's (SDL) RWops i/o abstraction.
+ *
+ * License: this code is public domain. I make no warranty that it is useful,
+ *  correct, harmless, or environmentally safe.
+ *
+ * This particular file may be used however you like, including copying it
+ *  verbatim into a closed-source project, exploiting it commercially, and
+ *  removing any trace of my name from the source (although I hope you won't
+ *  do that). I welcome enhancements and corrections to this file, but I do
+ *  not require you to send me patches if you make changes. This code has
+ *  NO WARRANTY.
+ *
+ * Unless otherwise stated, the rest of PhysicsFS falls under the zlib license.
+ *  Please see LICENSE.txt in the root of the source tree.
+ *
+ * SDL 1.2 falls under the LGPL license. SDL 1.3+ is zlib, like PhysicsFS.
+ *  You can get SDL at http://www.libsdl.org/
+ *
+ *  This file was written by Ryan C. Gordon. (icculus@icculus.org).
+ */
+
+#include <stdio.h>  /* used for SEEK_SET, SEEK_CUR, SEEK_END ... */
+#include "physfsrwops.h"
+
+/* SDL's RWOPS interface changed a little in SDL 1.3... */
+#if defined(SDL_VERSION_ATLEAST)
+#if SDL_VERSION_ATLEAST(1, 3, 0)
+#define TARGET_SDL13 1
+#endif
+#endif
+
+#if TARGET_SDL13
+static long SDLCALL physfsrwops_seek(struct SDL_RWops *rw, long offset, int whence)
+#else
+static int physfsrwops_seek(SDL_RWops *rw, int offset, int whence)
+#endif
+{
+    PHYSFS_File *handle = (PHYSFS_File *) rw->hidden.unknown.data1;
+    PHYSFS_sint64 pos = 0;
+
+    if (whence == SEEK_SET)
+        pos = (PHYSFS_sint64) offset;
+
+    else if (whence == SEEK_CUR)
+    {
+        const PHYSFS_sint64 current = PHYSFS_tell(handle);
+        if (current == -1)
+        {
+            SDL_SetError("Can't find position in file: %s",
+                          PHYSFS_getLastError());
+            return -1;
+        } /* if */
+
+        if (offset == 0)  /* this is a "tell" call. We're done. */
+        {
+            #if TARGET_SDL13
+            return (long) current;
+            #else
+            return (int) current;
+            #endif
+        } /* if */
+
+        pos = current + ((PHYSFS_sint64) offset);
+    } /* else if */
+
+    else if (whence == SEEK_END)
+    {
+        const PHYSFS_sint64 len = PHYSFS_fileLength(handle);
+        if (len == -1)
+        {
+            SDL_SetError("Can't find end of file: %s", PHYSFS_getLastError());
+            return -1;
+        } /* if */
+
+        pos = len + ((PHYSFS_sint64) offset);
+    } /* else if */
+
+    else
+    {
+        SDL_SetError("Invalid 'whence' parameter.");
+        return -1;
+    } /* else */
+
+    if ( pos < 0 )
+    {
+        SDL_SetError("Attempt to seek past start of file.");
+        return -1;
+    } /* if */
+    
+    if (!PHYSFS_seek(handle, (PHYSFS_uint64) pos))
+    {
+        SDL_SetError("PhysicsFS error: %s", PHYSFS_getLastError());
+        return -1;
+    } /* if */
+
+    #if TARGET_SDL13
+    return (long) pos;
+    #else
+    return (int) pos;
+    #endif
+} /* physfsrwops_seek */
+
+
+#if TARGET_SDL13
+static size_t SDLCALL physfsrwops_read(struct SDL_RWops *rw, void *ptr,
+                                       size_t size, size_t maxnum)
+#else
+static int physfsrwops_read(SDL_RWops *rw, void *ptr, int size, int maxnum)
+#endif
+{
+    PHYSFS_File *handle = (PHYSFS_File *) rw->hidden.unknown.data1;
+    const PHYSFS_uint64 readlen = (PHYSFS_uint64) (maxnum * size);
+    const PHYSFS_sint64 rc = PHYSFS_readBytes(handle, ptr, readlen);
+    if (rc != ((PHYSFS_sint64) readlen))
+    {
+        if (!PHYSFS_eof(handle)) /* not EOF? Must be an error. */
+            SDL_SetError("PhysicsFS error: %s", PHYSFS_getLastError());
+    } /* if */
+
+    #if TARGET_SDL13
+    return (size_t) rc;
+    #else
+    return (int) rc;
+    #endif
+} /* physfsrwops_read */
+
+
+#if TARGET_SDL13
+static size_t SDLCALL physfsrwops_write(struct SDL_RWops *rw, const void *ptr,
+                                        size_t size, size_t num)
+#else
+static int physfsrwops_write(SDL_RWops *rw, const void *ptr, int size, int num)
+#endif
+{
+    PHYSFS_File *handle = (PHYSFS_File *) rw->hidden.unknown.data1;
+    const PHYSFS_uint64 writelen = (PHYSFS_uint64) (num * size);
+    const PHYSFS_sint64 rc = PHYSFS_writeBytes(handle, ptr, writelen);
+    if (rc != ((PHYSFS_sint64) writelen))
+        SDL_SetError("PhysicsFS error: %s", PHYSFS_getLastError());
+
+    #if TARGET_SDL13
+    return (size_t) rc;
+    #else
+    return (int) rc;
+    #endif
+} /* physfsrwops_write */
+
+
+static int physfsrwops_close(SDL_RWops *rw)
+{
+    PHYSFS_File *handle = (PHYSFS_File *) rw->hidden.unknown.data1;
+    if (!PHYSFS_close(handle))
+    {
+        SDL_SetError("PhysicsFS error: %s", PHYSFS_getLastError());
+        return -1;
+    } /* if */
+
+    SDL_FreeRW(rw);
+    return 0;
+} /* physfsrwops_close */
+
+
+static SDL_RWops *create_rwops(PHYSFS_File *handle)
+{
+    SDL_RWops *retval = NULL;
+
+    if (handle == NULL)
+        SDL_SetError("PhysicsFS error: %s", PHYSFS_getLastError());
+    else
+    {
+        retval = SDL_AllocRW();
+        if (retval != NULL)
+        {
+            retval->seek  = physfsrwops_seek;
+            retval->read  = physfsrwops_read;
+            retval->write = physfsrwops_write;
+            retval->close = physfsrwops_close;
+            retval->hidden.unknown.data1 = handle;
+        } /* if */
+    } /* else */
+
+    return retval;
+} /* create_rwops */
+
+
+SDL_RWops *PHYSFSRWOPS_makeRWops(PHYSFS_File *handle)
+{
+    SDL_RWops *retval = NULL;
+    if (handle == NULL)
+        SDL_SetError("NULL pointer passed to PHYSFSRWOPS_makeRWops().");
+    else
+        retval = create_rwops(handle);
+
+    return retval;
+} /* PHYSFSRWOPS_makeRWops */
+
+
+SDL_RWops *PHYSFSRWOPS_openRead(const char *fname)
+{
+    return create_rwops(PHYSFS_openRead(fname));
+} /* PHYSFSRWOPS_openRead */
+
+
+SDL_RWops *PHYSFSRWOPS_openWrite(const char *fname)
+{
+    return create_rwops(PHYSFS_openWrite(fname));
+} /* PHYSFSRWOPS_openWrite */
+
+
+SDL_RWops *PHYSFSRWOPS_openAppend(const char *fname)
+{
+    return create_rwops(PHYSFS_openAppend(fname));
+} /* PHYSFSRWOPS_openAppend */
+
+
+/* end of physfsrwops.c ... */
+