X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=libavutil%2Ffifo.h;h=22a9aa5d189f14f9ab668c4f16f366598b5a10f3;hb=f863cdef813e51d5850e2386618feafe197f06f4;hp=999d0bf89b9660b5b0a2817dca5809e48b092815;hpb=5271b857ebc7ddcfa2d0dc6604f55ef43d2bc49e;p=ffmpeg

diff --git a/libavutil/fifo.h b/libavutil/fifo.h
index 999d0bf89b9..22a9aa5d189 100644
--- a/libavutil/fifo.h
+++ b/libavutil/fifo.h
@@ -25,6 +25,7 @@
 #define AVUTIL_FIFO_H
 
 #include <stdint.h>
+#include "avutil.h"
 
 typedef struct AVFifoBuffer {
     uint8_t *buffer;
@@ -41,20 +42,20 @@ AVFifoBuffer *av_fifo_alloc(unsigned int size);
 
 /**
  * Free an AVFifoBuffer.
- * @param *f AVFifoBuffer to free
+ * @param f AVFifoBuffer to free
  */
 void av_fifo_free(AVFifoBuffer *f);
 
 /**
  * Reset the AVFifoBuffer to the state right after av_fifo_alloc, in particular it is emptied.
- * @param *f AVFifoBuffer to reset
+ * @param f AVFifoBuffer to reset
  */
 void av_fifo_reset(AVFifoBuffer *f);
 
 /**
  * Return the amount of data in bytes in the AVFifoBuffer, that is the
  * amount of data you can read from it.
- * @param *f AVFifoBuffer to read from
+ * @param f AVFifoBuffer to read from
  * @return size
  */
 int av_fifo_size(AVFifoBuffer *f);
@@ -62,27 +63,27 @@ int av_fifo_size(AVFifoBuffer *f);
 /**
  * Return the amount of space in bytes in the AVFifoBuffer, that is the
  * amount of data you can write into it.
- * @param *f AVFifoBuffer to write into
+ * @param f AVFifoBuffer to write into
  * @return size
  */
 int av_fifo_space(AVFifoBuffer *f);
 
 /**
  * Feed data from an AVFifoBuffer to a user-supplied callback.
- * @param *f AVFifoBuffer to read from
+ * @param f AVFifoBuffer to read from
  * @param buf_size number of bytes to read
- * @param *func generic read function
- * @param *dest data destination
+ * @param func generic read function
+ * @param dest data destination
  */
 int av_fifo_generic_read(AVFifoBuffer *f, void *dest, int buf_size, void (*func)(void*, void*, int));
 
 /**
  * Feed data from a user-supplied callback to an AVFifoBuffer.
- * @param *f AVFifoBuffer to write to
- * @param *src data source; non-const since it may be used as a
+ * @param f AVFifoBuffer to write to
+ * @param src data source; non-const since it may be used as a
  * modifiable context by the function defined in func
  * @param size number of bytes to write
- * @param *func generic write function; the first parameter is src,
+ * @param func generic write function; the first parameter is src,
  * the second is dest_buf, the 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.
@@ -93,7 +94,9 @@ int av_fifo_generic_write(AVFifoBuffer *f, void *src, int size, int (*func)(void
 
 /**
  * Resize an AVFifoBuffer.
- * @param *f AVFifoBuffer to resize
+ * In case of reallocation failure, the old FIFO is kept unchanged.
+ *
+ * @param f AVFifoBuffer to resize
  * @param size new AVFifoBuffer size in bytes
  * @return <0 for failure, >=0 otherwise
  */
@@ -101,16 +104,40 @@ int av_fifo_realloc2(AVFifoBuffer *f, unsigned int size);
 
 /**
  * Read and discard the specified amount of data from an AVFifoBuffer.
- * @param *f AVFifoBuffer to read from
+ * @param f AVFifoBuffer to read from
  * @param size amount of data to read in bytes
  */
 void av_fifo_drain(AVFifoBuffer *f, int size);
 
-static inline uint8_t av_fifo_peek(AVFifoBuffer *f, int offs)
+/**
+ * Return a pointer to the data stored in a FIFO buffer at a certain offset.
+ * The FIFO buffer is not modified.
+ *
+ * @param f    AVFifoBuffer to peek at, f must be non-NULL
+ * @param offs an offset in bytes, its absolute value must be less
+ *             than the used buffer size or the returned pointer will
+ *             point outside to the buffer data.
+ *             The used buffer size can be checked with av_fifo_size().
+ */
+static inline uint8_t *av_fifo_peek2(const AVFifoBuffer *f, int offs)
 {
     uint8_t *ptr = f->rptr + offs;
     if (ptr >= f->end)
-        ptr -= f->end - f->buffer;
-    return *ptr;
+        ptr = f->buffer + (ptr - f->end);
+    else if (ptr < f->buffer)
+        ptr = f->end - (f->buffer - ptr);
+    return ptr;
+}
+
+#if FF_API_AV_FIFO_PEEK
+/**
+ * @deprecated Use av_fifo_peek2() instead.
+ */
+attribute_deprecated
+static inline uint8_t av_fifo_peek(AVFifoBuffer *f, int offs)
+{
+    return *av_fifo_peek2(f, offs);
 }
+#endif
+
 #endif /* AVUTIL_FIFO_H */