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authorJeremy Andrews <athenian200@outlook.com>2021-09-26 13:48:44 -0500
committerJeremy Andrews <athenian200@outlook.com>2021-09-26 13:48:44 -0500
commit032e39643a289df092067142058dfd4e59667d52 (patch)
tree7877b1fba3ee0baf7d9c87af9d3f8cb264e182b3 /libs/ffvpx/libavutil/fifo.c
parentcc621e1829f61df96473cd04fb8ba27a65c99e13 (diff)
downloadaura-central-032e39643a289df092067142058dfd4e59667d52.tar.gz
Issue %3003 - Move ffvpx to libs/
Diffstat (limited to 'libs/ffvpx/libavutil/fifo.c')
-rw-r--r--libs/ffvpx/libavutil/fifo.c240
1 files changed, 240 insertions, 0 deletions
diff --git a/libs/ffvpx/libavutil/fifo.c b/libs/ffvpx/libavutil/fifo.c
new file mode 100644
index 000000000..1060aedf1
--- /dev/null
+++ b/libs/ffvpx/libavutil/fifo.c
@@ -0,0 +1,240 @@
+/*
+ * 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.
+ *
+ * FFmpeg 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,
+ * 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
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "avassert.h"
+#include "common.h"
+#include "fifo.h"
+
+static AVFifoBuffer *fifo_alloc_common(void *buffer, size_t size)
+{
+ AVFifoBuffer *f;
+ if (!buffer)
+ return NULL;
+ f = av_mallocz(sizeof(AVFifoBuffer));
+ if (!f) {
+ av_free(buffer);
+ return NULL;
+ }
+ f->buffer = buffer;
+ f->end = f->buffer + size;
+ av_fifo_reset(f);
+ return f;
+}
+
+AVFifoBuffer *av_fifo_alloc(unsigned int size)
+{
+ void *buffer = av_malloc(size);
+ return fifo_alloc_common(buffer, size);
+}
+
+AVFifoBuffer *av_fifo_alloc_array(size_t nmemb, size_t size)
+{
+ void *buffer = av_malloc_array(nmemb, size);
+ return fifo_alloc_common(buffer, nmemb * size);
+}
+
+void av_fifo_free(AVFifoBuffer *f)
+{
+ if (f) {
+ av_freep(&f->buffer);
+ av_free(f);
+ }
+}
+
+void av_fifo_freep(AVFifoBuffer **f)
+{
+ if (f) {
+ av_fifo_free(*f);
+ *f = NULL;
+ }
+}
+
+void av_fifo_reset(AVFifoBuffer *f)
+{
+ f->wptr = f->rptr = f->buffer;
+ f->wndx = f->rndx = 0;
+}
+
+int av_fifo_size(const AVFifoBuffer *f)
+{
+ return (uint32_t)(f->wndx - f->rndx);
+}
+
+int av_fifo_space(const 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;
+
+ if (old_size < new_size) {
+ int len = av_fifo_size(f);
+ AVFifoBuffer *f2 = av_fifo_alloc(new_size);
+
+ if (!f2)
+ return AVERROR(ENOMEM);
+ av_fifo_generic_read(f, f2->buffer, len, NULL);
+ f2->wptr += len;
+ f2->wndx += len;
+ av_free(f->buffer);
+ *f = *f2;
+ av_free(f2);
+ }
+ return 0;
+}
+
+int av_fifo_grow(AVFifoBuffer *f, unsigned int size)
+{
+ unsigned int old_size = f->end - f->buffer;
+ if(size + (unsigned)av_fifo_size(f) < size)
+ return AVERROR(EINVAL);
+
+ size += av_fifo_size(f);
+
+ if (old_size < size)
+ return av_fifo_realloc2(f, FFMAX(size, 2*old_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;
+ uint32_t wndx= f->wndx;
+ uint8_t *wptr= f->wptr;
+
+ do {
+ int len = FFMIN(f->end - wptr, size);
+ if (func) {
+ len = func(src, wptr, len);
+ if (len <= 0)
+ break;
+ } else {
+ memcpy(wptr, src, len);
+ src = (uint8_t *)src + len;
+ }
+// Write memory barrier needed for SMP here in theory
+ wptr += len;
+ if (wptr >= f->end)
+ wptr = f->buffer;
+ wndx += len;
+ size -= len;
+ } while (size > 0);
+ f->wndx= wndx;
+ f->wptr= wptr;
+ return total - size;
+}
+
+int av_fifo_generic_peek_at(AVFifoBuffer *f, void *dest, int offset, int buf_size, void (*func)(void*, void*, int))
+{
+ uint8_t *rptr = f->rptr;
+
+ av_assert2(offset >= 0);
+
+ /*
+ * *ndx are indexes modulo 2^32, they are intended to overflow,
+ * to handle *ndx greater than 4gb.
+ */
+ av_assert2(buf_size + (unsigned)offset <= f->wndx - f->rndx);
+
+ if (offset >= f->end - rptr)
+ rptr += offset - (f->end - f->buffer);
+ else
+ rptr += offset;
+
+ while (buf_size > 0) {
+ int len;
+
+ if (rptr >= f->end)
+ rptr -= f->end - f->buffer;
+
+ len = FFMIN(f->end - rptr, buf_size);
+ if (func)
+ func(dest, rptr, len);
+ else {
+ memcpy(dest, rptr, len);
+ dest = (uint8_t *)dest + len;
+ }
+
+ buf_size -= len;
+ rptr += len;
+ }
+
+ return 0;
+}
+
+int av_fifo_generic_peek(AVFifoBuffer *f, void *dest, int buf_size,
+ void (*func)(void *, void *, int))
+{
+// Read memory barrier needed for SMP here in theory
+ uint8_t *rptr = f->rptr;
+
+ do {
+ int len = FFMIN(f->end - rptr, buf_size);
+ if (func)
+ func(dest, rptr, len);
+ else {
+ memcpy(dest, rptr, len);
+ dest = (uint8_t *)dest + len;
+ }
+// memory barrier needed for SMP here in theory
+ rptr += len;
+ if (rptr >= f->end)
+ rptr -= f->end - f->buffer;
+ buf_size -= len;
+ } while (buf_size > 0);
+
+ return 0;
+}
+
+int av_fifo_generic_read(AVFifoBuffer *f, void *dest, int buf_size,
+ void (*func)(void *, void *, int))
+{
+// 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 {
+ memcpy(dest, f->rptr, 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. */
+void av_fifo_drain(AVFifoBuffer *f, int size)
+{
+ av_assert2(av_fifo_size(f) >= size);
+ f->rptr += size;
+ if (f->rptr >= f->end)
+ f->rptr -= f->end - f->buffer;
+ f->rndx += size;
+}