intfloat_readwrite: fix signed addition overflows

[ffmpeg] / libavutil / fifo.c

diff --git a/libavutil/fifo.c b/libavutil/fifo.c
index 52ace0e22c8a0f7a671387a4bd44853e1b28cd54..5774d33d256b2b1944f4c09a2b23ad3e05f6a01a 100644 (file)
--- a/libavutil/fifo.c
+++ b/libavutil/fifo.c
@@ -3,20 +3,20 @@
  * Copyright (c) 2000, 2001, 2002 Fabrice Bellard
  * Copyright (c) 2006 Roman Shaposhnik
  *
- * This file is part of FFmpeg.
+ * This file is part of Libav.
  *
- * FFmpeg is free software; you can redistribute it and/or
+ * Libav is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation; either
  * version 2.1 of the License, or (at your option) any later version.
  *
- * FFmpeg is distributed in the hope that it will be useful,
+ * Libav is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with FFmpeg; if not, write to the Free Software
+ * License along with Libav; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 #include "common.h"
@@ -54,6 +54,11 @@ int av_fifo_size(AVFifoBuffer *f)
     return (uint32_t)(f->wndx - f->rndx);
 }
 
+int av_fifo_space(AVFifoBuffer *f)
+{
+    return f->end - f->buffer - av_fifo_size(f);
+}
+
 int av_fifo_realloc2(AVFifoBuffer *f, unsigned int new_size) {
     unsigned int old_size= f->end - f->buffer;
 
@@ -73,6 +78,7 @@ int av_fifo_realloc2(AVFifoBuffer *f, unsigned int new_size) {
     return 0;
 }
 
+// src must NOT be const as it can be a context for func that may need updating (like a pointer or byte counter)
 int av_fifo_generic_write(AVFifoBuffer *f, void *src, int size, int (*func)(void*, void*, int))
 {
     int total = size;
@@ -121,3 +127,39 @@ void av_fifo_drain(AVFifoBuffer *f, int size)
         f->rptr -= f->end - f->buffer;
     f->rndx += size;
 }
+
+#ifdef TEST
+
+#undef printf
+
+int main(void)
+{
+    /* create a FIFO buffer */
+    AVFifoBuffer *fifo = av_fifo_alloc(13 * sizeof(int));
+    int i, j, n;
+
+    /* fill data */
+    for (i = 0; av_fifo_space(fifo) >= sizeof(int); i++)
+        av_fifo_generic_write(fifo, &i, sizeof(int), NULL);
+
+    /* peek at FIFO */
+    n = av_fifo_size(fifo)/sizeof(int);
+    for (i = -n+1; i < n; i++) {
+        int *v = (int *)av_fifo_peek2(fifo, i*sizeof(int));
+        printf("%d: %d\n", i, *v);
+    }
+    printf("\n");
+
+    /* read data */
+    for (i = 0; av_fifo_size(fifo) >= sizeof(int); i++) {
+        av_fifo_generic_read(fifo, &j, sizeof(int), NULL);
+        printf("%d ", j);
+    }
+    printf("\n");
+
+    av_fifo_free(fifo);
+
+    return 0;
+}
+
+#endif