Add a generic write function to av_fifo.

Patch by Björn Axelsson: bjorn axelsson intinor se
Original thread: [FFmpeg-devel] [RFC][PATCH] av_fifo_write_from_bytestream()
Date: 04/03/2008 12:14 PM

Originally committed as revision 12773 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavutil/fifo.c

@@ -73,15 +73,27 @@ void av_fifo_realloc(AVFifoBuffer *f, unsigned int new_size) {
 
 void av_fifo_write(AVFifoBuffer *f, const uint8_t *buf, int size)
 {
+    av_fifo_generic_write(f, (void *)buf, size, NULL);
+}
+
+int av_fifo_generic_write(AVFifoBuffer *f, void *buf, int size, int (*func)(void*, void*, int))
+{
+    int total = size;
     do {
         int len = FFMIN(f->end - f->wptr, size);
+        if(func) {
+            if(func(buf, f->wptr, len) <= 0)
+                break;
+        } else {
         memcpy(f->wptr, buf, len);
+            buf = (uint8_t*)buf + len;
+        }
         f->wptr += len;
         if (f->wptr >= f->end)
             f->wptr = f->buffer;
-        buf += len;
         size -= len;
     } while (size > 0);
+    return total - size;
 }
 
 

libavutil/fifo.h

@@ -76,7 +76,21 @@ int av_fifo_generic_read(AVFifoBuffer *f, int buf_size, void (*func)(void*, void
  * @param *buf data source
  * @param size data size
  */
-void av_fifo_write(AVFifoBuffer *f, const uint8_t *buf, int size);
+attribute_deprecated void av_fifo_write(AVFifoBuffer *f, const uint8_t *buf, int size);
+
+/**
+ * Feeds data from a user supplied callback to an AVFifoBuffer.
+ * @param *f AVFifoBuffer to write to
+ * @param *buf data source
+ * @param size number of bytes to write
+ * @param *func generic write function. First parameter is buf,
+ * second is dest_buf, third is dest_buf_size.
+ * func must return the number of bytes written to dest_buf, or <= 0 to
+ * indicate no more data available to write.
+ * If func is NULL, buf is interpreted as a simple byte array for source data.
+ * @return the number of bytes written to the fifo.
+ */
+int av_fifo_generic_write(AVFifoBuffer *f, void *buf, int size, int (*func)(void*, void*, int));
 
 /**
  * Resizes an AVFifoBuffer.