added primitive aborting system

Originally committed as revision 2058 to svn://svn.ffmpeg.org/ffmpeg/trunk

1 files changed, 22 insertions, 0 deletions

diff --git a/libavformat/avio.c b/libavformat/avio.c
index 3cd9e4d991..2c25c8a059 100644
--- a/libavformat/avio.c
+++ b/libavformat/avio.c
@@ -19,7 +19,10 @@
 #include "avformat.h"
 #include <ctype.h>
 
+static int default_interrupt_cb(void);
+
 URLProtocol *first_protocol = NULL;
+URLInterruptCB *url_interrupt_cb = default_interrupt_cb;
 
 int register_protocol(URLProtocol *protocol)
 {
@@ -165,3 +168,22 @@ void url_get_filename(URLContext *h, char *buf, int buf_size)
 {
     pstrcpy(buf, buf_size, h->filename);
 }
+
+
+static int default_interrupt_cb(void)
+{
+    return 0;
+}
+
+/** 
+ * The callback is called in blocking functions to test regulary if
+ * asynchronous interruption is needed. -EINTR is returned in this
+ * case by the interrupted function. 'NULL' means no interrupt
+ * callback is given.  
+ */
+void url_set_interrupt_cb(URLInterruptCB *interrupt_cb)
+{
+    if (!interrupt_cb)
+        interrupt_cb = default_interrupt_cb;
+    url_interrupt_cb = interrupt_cb;
+}