static int v4l2_receive_packet(AVCodecContext *avctx, AVPacket *avpkt)
{
V4L2m2mContext *s = avctx->priv_data;
V4L2Context *const capture = &s->capture;
V4L2Context *const output = &s->output;
int ret;
if (s->draining)
goto dequeue;
if (!output->streamon) {
ret = ff_v4l2_context_set_status(output, VIDIOC_STREAMON);
if (ret) {
av_log(avctx, AV_LOG_ERROR, "VIDIOC_STREAMOFF failed on output context\n");
return ret;
}
}
if (!capture->streamon) {
ret = ff_v4l2_context_set_status(capture, VIDIOC_STREAMON);
if (ret) {
av_log(avctx, AV_LOG_ERROR, "VIDIOC_STREAMON failed on capture context\n");
return ret;
}
}
dequeue:
return ff_v4l2_context_dequeue_packet(capture, avpkt);
}
static int v4l2_stop_decode(V4L2Context *ctx)
{
struct v4l2_decoder_cmd cmd = {
.cmd = V4L2_DEC_CMD_STOP,
.flags = 0,
};
int ret;
ret = ioctl(ctx_to_m2mctx(ctx)->fd, VIDIOC_DECODER_CMD, &cmd);
if (ret) {
/* DECODER_CMD is optional */
if (errno == ENOTTY)
return ff_v4l2_context_set_status(ctx, VIDIOC_STREAMOFF);
}
return 0;
}
static int v4l2_stop_encode(V4L2Context *ctx)
{
struct v4l2_encoder_cmd cmd = {
.cmd = V4L2_ENC_CMD_STOP,
.flags = 0,
};
int ret;
ret = ioctl(ctx_to_m2mctx(ctx)->fd, VIDIOC_ENCODER_CMD, &cmd);
if (ret) {
/* ENCODER_CMD is optional */
if (errno == ENOTTY)
return ff_v4l2_context_set_status(ctx, VIDIOC_STREAMOFF);
}
return 0;
}
static V4L2Buffer* v4l2_dequeue_v4l2buf(V4L2Context *ctx, int timeout)
{
struct v4l2_plane planes[VIDEO_MAX_PLANES];
struct v4l2_buffer buf = { 0 };
V4L2Buffer* avbuf = NULL;
struct pollfd pfd = {
.events = POLLIN | POLLRDNORM | POLLPRI | POLLOUT | POLLWRNORM, /* default blocking capture */
.fd = ctx_to_m2mctx(ctx)->fd,
};
int i, ret;
/* if we are draining and there are no more capture buffers queued in the driver we are done */
if (!V4L2_TYPE_IS_OUTPUT(ctx->type) && ctx_to_m2mctx(ctx)->draining) {
for (i = 0; i < ctx->num_buffers; i++) {
if (ctx->buffers[i].status == V4L2BUF_IN_DRIVER)
goto start;
}
ctx->done = 1;
return NULL;
}
start:
if (V4L2_TYPE_IS_OUTPUT(ctx->type))
pfd.events = POLLOUT | POLLWRNORM;
else {
/* no need to listen to requests for more input while draining */
if (ctx_to_m2mctx(ctx)->draining)
pfd.events = POLLIN | POLLRDNORM | POLLPRI;
}
for (;;) {
ret = poll(&pfd, 1, timeout);
if (ret > 0)
break;
if (errno == EINTR)
continue;
return NULL;
}
/* 0. handle errors */
if (pfd.revents & POLLERR) {
/* if we are trying to get free buffers but none have been queued yet
no need to raise a warning */
if (timeout == 0) {
for (i = 0; i < ctx->num_buffers; i++) {
if (ctx->buffers[i].status != V4L2BUF_AVAILABLE)
av_log(logger(ctx), AV_LOG_WARNING, "%s POLLERR\n", ctx->name);
}
}
else
av_log(logger(ctx), AV_LOG_WARNING, "%s POLLERR\n", ctx->name);
return NULL;
}
/* 1. handle resolution changes */
if (pfd.revents & POLLPRI) {
ret = v4l2_handle_event(ctx);
if (ret < 0) {
/* if re-init failed, abort */
ctx->done = 1;
return NULL;
}
if (ret) {
/* if re-init was successful drop the buffer (if there was one)
* since we had to reconfigure capture (unmap all buffers)
*/
return NULL;
}
}
/* 2. dequeue the buffer */
if (pfd.revents & (POLLIN | POLLRDNORM | POLLOUT | POLLWRNORM)) {
if (!V4L2_TYPE_IS_OUTPUT(ctx->type)) {
/* there is a capture buffer ready */
if (pfd.revents & (POLLIN | POLLRDNORM))
goto dequeue;
/* the driver is ready to accept more input; instead of waiting for the capture
* buffer to complete we return NULL so input can proceed (we are single threaded)
*/
if (pfd.revents & (POLLOUT | POLLWRNORM))
return NULL;
}
dequeue:
memset(&buf, 0, sizeof(buf));
buf.memory = V4L2_MEMORY_MMAP;
buf.type = ctx->type;
if (V4L2_TYPE_IS_MULTIPLANAR(ctx->type)) {
memset(planes, 0, sizeof(planes));
buf.length = VIDEO_MAX_PLANES;
buf.m.planes = planes;
}
ret = ioctl(ctx_to_m2mctx(ctx)->fd, VIDIOC_DQBUF, &buf);
if (ret) {
if (errno != EAGAIN) {
ctx->done = 1;
if (errno != EPIPE)
av_log(logger(ctx), AV_LOG_DEBUG, "%s VIDIOC_DQBUF, errno (%s)\n",
ctx->name, av_err2str(AVERROR(errno)));
}
return NULL;
}
avbuf = &ctx->buffers[buf.index];
avbuf->status = V4L2BUF_AVAILABLE;
avbuf->buf = buf;
if (V4L2_TYPE_IS_MULTIPLANAR(ctx->type)) {
memcpy(avbuf->planes, planes, sizeof(planes));
avbuf->buf.m.planes = avbuf->planes;
}
return avbuf;
}
return NULL;
}
static V4L2Buffer* v4l2_getfree_v4l2buf(V4L2Context *ctx)
{
int timeout = 0; /* return when no more buffers to dequeue */
int i;
/* get back as many output buffers as possible */
if (V4L2_TYPE_IS_OUTPUT(ctx->type)) {
do {
} while (v4l2_dequeue_v4l2buf(ctx, timeout));
}
for (i = 0; i < ctx->num_buffers; i++) {
if (ctx->buffers[i].status == V4L2BUF_AVAILABLE)
return &ctx->buffers[i];
}
return NULL;
}
static int v4l2_release_buffers(V4L2Context* ctx)
{
struct v4l2_requestbuffers req = {
.memory = V4L2_MEMORY_MMAP,
.type = ctx->type,
.count = 0, /* 0 -> unmaps buffers from the driver */
};
int i, j;
for (i = 0; i < ctx->num_buffers; i++) {
V4L2Buffer *buffer = &ctx->buffers[i];
for (j = 0; j < buffer->num_planes; j++) {
struct V4L2Plane_info *p = &buffer->plane_info[j];
if (p->mm_addr && p->length)
if (munmap(p->mm_addr, p->length) < 0)
av_log(logger(ctx), AV_LOG_ERROR, "%s unmap plane (%s))\n", ctx->name, av_err2str(AVERROR(errno)));
}
}
return ioctl(ctx_to_m2mctx(ctx)->fd, VIDIOC_REQBUFS, &req);
}
static inline int v4l2_try_raw_format(V4L2Context* ctx, enum AVPixelFormat pixfmt)
{
struct v4l2_format *fmt = &ctx->format;
uint32_t v4l2_fmt;
int ret;
v4l2_fmt = ff_v4l2_format_avfmt_to_v4l2(pixfmt);
if (!v4l2_fmt)
return AVERROR(EINVAL);
if (V4L2_TYPE_IS_MULTIPLANAR(ctx->type))
fmt->fmt.pix_mp.pixelformat = v4l2_fmt;
else
fmt->fmt.pix.pixelformat = v4l2_fmt;
fmt->type = ctx->type;
ret = ioctl(ctx_to_m2mctx(ctx)->fd, VIDIOC_TRY_FMT, fmt);
if (ret)
return AVERROR(EINVAL);
return 0;
}
static int v4l2_get_raw_format(V4L2Context* ctx, enum AVPixelFormat *p)
{
enum AVPixelFormat pixfmt = ctx->av_pix_fmt;
struct v4l2_fmtdesc fdesc;
int ret;
memset(&fdesc, 0, sizeof(fdesc));
fdesc.type = ctx->type;
if (pixfmt != AV_PIX_FMT_NONE) {
ret = v4l2_try_raw_format(ctx, pixfmt);
if (!ret)
return 0;
}
for (;;) {
ret = ioctl(ctx_to_m2mctx(ctx)->fd, VIDIOC_ENUM_FMT, &fdesc);
if (ret)
return AVERROR(EINVAL);
pixfmt = ff_v4l2_format_v4l2_to_avfmt(fdesc.pixelformat, AV_CODEC_ID_RAWVIDEO);
ret = v4l2_try_raw_format(ctx, pixfmt);
if (ret){
fdesc.index++;
continue;
}
*p = pixfmt;
return 0;
}
return AVERROR(EINVAL);
}
static int v4l2_get_coded_format(V4L2Context* ctx, uint32_t *p)
{
struct v4l2_fmtdesc fdesc;
uint32_t v4l2_fmt;
int ret;
/* translate to a valid v4l2 format */
v4l2_fmt = ff_v4l2_format_avcodec_to_v4l2(ctx->av_codec_id);
if (!v4l2_fmt)
return AVERROR(EINVAL);
/* check if the driver supports this format */
memset(&fdesc, 0, sizeof(fdesc));
fdesc.type = ctx->type;
for (;;) {
ret = ioctl(ctx_to_m2mctx(ctx)->fd, VIDIOC_ENUM_FMT, &fdesc);
if (ret)
return AVERROR(EINVAL);
if (fdesc.pixelformat == v4l2_fmt)
break;
fdesc.index++;
}
*p = v4l2_fmt;
return 0;
}
/*****************************************************************************
*
* V4L2 Context Interface
*
*****************************************************************************/
int ff_v4l2_context_set_status(V4L2Context* ctx, uint32_t cmd)
{
int type = ctx->type;
int ret;
ret = ioctl(ctx_to_m2mctx(ctx)->fd, cmd, &type);
if (ret < 0)
return AVERROR(errno);
ctx->streamon = (cmd == VIDIOC_STREAMON);
return 0;
}
int ff_v4l2_context_enqueue_frame(V4L2Context* ctx, const AVFrame* frame)
{
V4L2m2mContext *s = ctx_to_m2mctx(ctx);
V4L2Buffer* avbuf;
int ret;
if (!frame) {
ret = v4l2_stop_encode(ctx);
if (ret)
av_log(logger(ctx), AV_LOG_ERROR, "%s stop_encode\n", ctx->name);
s->draining= 1;
return 0;
}
avbuf = v4l2_getfree_v4l2buf(ctx);
if (!avbuf)
return AVERROR(ENOMEM);
ret = ff_v4l2_buffer_avframe_to_buf(frame, avbuf);
if (ret)
return ret;
return ff_v4l2_buffer_enqueue(avbuf);
}
int ff_v4l2_context_enqueue_packet(V4L2Context* ctx, const AVPacket* pkt)
{
V4L2m2mContext *s = ctx_to_m2mctx(ctx);
V4L2Buffer* avbuf;
int ret;
if (!pkt->size) {
ret = v4l2_stop_decode(ctx);
if (ret)
av_log(logger(ctx), AV_LOG_ERROR, "%s stop_decode\n", ctx->name);
s->draining = 1;
return 0;
}
avbuf = v4l2_getfree_v4l2buf(ctx);
if (!avbuf)
return AVERROR(ENOMEM);
ret = ff_v4l2_buffer_avpkt_to_buf(pkt, avbuf);
if (ret)
return ret;
return ff_v4l2_buffer_enqueue(avbuf);
}
