Handle AVSEEK_FORCE

3 files changed, 11 insertions, 12 deletions

diff --git a/examples/example_custom.c b/examples/example_custom.c
index 2f84b99..d666550 100644
--- a/examples/example_custom.c
+++ b/examples/example_custom.c
@@ -24,8 +24,8 @@ int read_callback(void *userdata, uint8_t *buf, int buf_size) {
 
 int64_t seek_callback(void *userdata, int64_t offset, int whence) {
     FILE *fd =  (FILE*)userdata;
-    if(whence == 3) { // AVSEEK_SIZE
-        return -1; // Not supported
+    if(whence != SEEK_SET && whence != SEEK_END && whence != SEEK_CUR) {
+        return -1; // AVSEEK_SIZE, AVSEEK_FORCE Not supported
     }
     if(fseek(fd, offset, whence)) {
         return ftell(fd);
diff --git a/include/kitchensink/kitsource.h b/include/kitchensink/kitsource.h
index 533e233..9b744ca 100644
--- a/include/kitchensink/kitsource.h
+++ b/include/kitchensink/kitsource.h
@@ -87,6 +87,8 @@ typedef int (*Kit_ReadCallback)(void *userdata, uint8_t *buf, int size);
  * - SEEK_CUR: Reference position is the current position of the file pointer
  * - SEEK_END: Reference position is the end of the file
  * - AVSEEK_SIZE: Optional. Does not seek, instead finds the size of the source file.
+ * - AVSEEK_FORCE: Optional. Suggests that seeking should be done at any cost. May be passed alongside
+ *   any of the SEEK_* flags, eg. SEEK_SET|AVSEEK_FORCE.
  * 
  * The function must return the position (in bytes) we seeked to or <0 on error or on unsupported operation.
  * 
diff --git a/src/kitsource.c b/src/kitsource.c
index fddb410..71a73b0 100644
--- a/src/kitsource.c
+++ b/src/kitsource.c
@@ -137,17 +137,14 @@ static int64_t _RWGetSize(SDL_RWops *rw_ops) {
 static int64_t _RWSeekCallback(void *userdata, int64_t offset, int whence) {
     int rw_whence = 0;
 
-    // Looking for file size. Will return size of -1 if not supported.
-    if(whence == AVSEEK_SIZE) {
+    if(whence & AVSEEK_SIZE)
         return _RWGetSize(userdata);
-    }
-
-    // RW and normal seeks *should* be the same, but it's not guaranteed by docs.
-    switch(whence) {
-        case SEEK_CUR: rw_whence = RW_SEEK_CUR; break;
-        case SEEK_SET: rw_whence = RW_SEEK_SET; break;
-        case SEEK_END: rw_whence = RW_SEEK_END; break;
-    }
+    if((whence & ~AVSEEK_FORCE) == SEEK_CUR)
+        rw_whence = RW_SEEK_CUR;
+    if((whence & ~AVSEEK_FORCE) == SEEK_SET)
+        rw_whence = RW_SEEK_SET;
+    if((whence & ~AVSEEK_FORCE) == SEEK_END)
+        rw_whence = RW_SEEK_END;
 
     if(SDL_RWseek((SDL_RWops*)userdata, offset, rw_whence) < 0) {
         return -1;