h264: move reading direct_spatial_mv_pred out of ff_set_ref_count()

[ffmpeg] / libavutil / fifo.c

diff --git a/libavutil/fifo.c b/libavutil/fifo.c
index b86d2629ee8211f5cef38ed01e56a8878800b438..a42899c2b302a57046acf55c59023693beaea3d6 100644 (file)
--- a/libavutil/fifo.c
+++ b/libavutil/fifo.c
@@ -1,114 +1,133 @@
 /*
- * A very simple circular buffer FIFO implementation
+ * a very simple circular buffer FIFO implementation
  * 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"
 #include "fifo.h"
 
-int av_fifo_init(AVFifoBuffer *f, int size)
+AVFifoBuffer *av_fifo_alloc(unsigned int size)
 {
-    f->wptr = f->rptr =
+    AVFifoBuffer *f = av_mallocz(sizeof(AVFifoBuffer));
+    if (!f)
+        return NULL;
     f->buffer = av_malloc(size);
-    f->end = f->buffer + size;
+    f->end    = f->buffer + size;
+    av_fifo_reset(f);
     if (!f->buffer)
-        return -1;
-    return 0;
+        av_freep(&f);
+    return f;
 }
 
 void av_fifo_free(AVFifoBuffer *f)
 {
-    av_free(f->buffer);
+    if (f) {
+        av_free(f->buffer);
+        av_free(f);
+    }
+}
+
+void av_fifo_reset(AVFifoBuffer *f)
+{
+    f->wptr = f->rptr = f->buffer;
+    f->wndx = f->rndx = 0;
 }
 
 int av_fifo_size(AVFifoBuffer *f)
 {
-    int size = f->wptr - f->rptr;
-    if (size < 0)
-        size += f->end - f->buffer;
-    return size;
+    return (uint32_t)(f->wndx - f->rndx);
 }
 
-/**
- * Get data from the fifo (returns -1 if not enough data).
- */
-int av_fifo_read(AVFifoBuffer *f, uint8_t *buf, int buf_size)
+int av_fifo_space(AVFifoBuffer *f)
 {
-    return av_fifo_generic_read(f, buf_size, NULL, buf);
+    return f->end - f->buffer - av_fifo_size(f);
 }
 
-/**
- * Resizes a FIFO.
- */
-void av_fifo_realloc(AVFifoBuffer *f, unsigned int new_size) {
-    unsigned int old_size= f->end - f->buffer;
+int av_fifo_realloc2(AVFifoBuffer *f, unsigned int new_size)
+{
+    unsigned int old_size = f->end - f->buffer;
 
-    if(old_size < new_size){
-        int len= av_fifo_size(f);
-        AVFifoBuffer f2;
+    if (old_size < new_size) {
+        int len          = av_fifo_size(f);
+        AVFifoBuffer *f2 = av_fifo_alloc(new_size);
 
-        av_fifo_init(&f2, new_size);
-        av_fifo_read(f, f2.buffer, len);
-        f2.wptr += len;
+        if (!f2)
+            return -1;
+        av_fifo_generic_read(f, f2->buffer, len, NULL);
+        f2->wptr += len;
+        f2->wndx += len;
         av_free(f->buffer);
-        *f= f2;
+        *f = *f2;
+        av_free(f2);
     }
+    return 0;
 }
 
-void av_fifo_write(AVFifoBuffer *f, const uint8_t *buf, int size)
+/* 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))
 {
-    while (size > 0) {
+    int total = size;
+    do {
         int len = FFMIN(f->end - f->wptr, size);
-        memcpy(f->wptr, buf, len);
+        if (func) {
+            if (func(src, f->wptr, len) <= 0)
+                break;
+        } else {
+            memcpy(f->wptr, src, len);
+            src = (uint8_t *)src + len;
+        }
+// Write memory barrier needed for SMP here in theory
         f->wptr += len;
         if (f->wptr >= f->end)
             f->wptr = f->buffer;
-        buf += len;
-        size -= len;
-    }
+        f->wndx += len;
+        size    -= len;
+    } while (size > 0);
+    return total - size;
 }
 
-
-/** get data from the fifo (return -1 if not enough data) */
-int av_fifo_generic_read(AVFifoBuffer *f, int buf_size, void (*func)(void*, void*, int), void* dest)
+int av_fifo_generic_read(AVFifoBuffer *f, void *dest, int buf_size,
+                         void (*func)(void *, void *, int))
 {
-    int size = av_fifo_size(f);
-
-    if (size < buf_size)
-        return -1;
-    while (buf_size > 0) {
+// Read memory barrier needed for SMP here in theory
+    do {
         int len = FFMIN(f->end - f->rptr, buf_size);
-        if(func) func(dest, f->rptr, len);
-        else{
+        if (func)
+            func(dest, f->rptr, len);
+        else {
             memcpy(dest, f->rptr, len);
-            dest = (uint8_t*)dest + len;
+            dest = (uint8_t *)dest + len;
         }
+// memory barrier needed for SMP here in theory
         av_fifo_drain(f, len);
         buf_size -= len;
-    }
+    } while (buf_size > 0);
     return 0;
 }
 
-/** discard data from the fifo */
+/** Discard data from the FIFO. */
 void av_fifo_drain(AVFifoBuffer *f, int size)
 {
     f->rptr += size;
     if (f->rptr >= f->end)
         f->rptr -= f->end - f->buffer;
+    f->rndx += size;
 }