static int v4l_do_mmap(V4lState *s){
struct video_mbuf vmbuf;
int err,i;
memset(&vmbuf,0,sizeof(vmbuf));
/* try to get mmap properties */
err=ioctl(s->fd,VIDIOCGMBUF,&vmbuf);
if (err<0){
ms_error("Could not get mmap properties: %s",strerror(errno));
return -1;
}else {
if (vmbuf.size>0){
/* do the mmap */
s->msize=vmbuf.size;
s->frame_max=vmbuf.frames;
} else {
ms_error("This device cannot support mmap.");
return -1;
}
}
s->mmapdbuf=mmap(NULL,s->msize,PROT_READ,MAP_SHARED,s->fd,0);
if (s->mmapdbuf==(void*)-1) {
/* for non-mmu arch */
s->mmapdbuf=mmap(NULL,s->msize,PROT_READ,MAP_PRIVATE,s->fd,0);
if (s->mmapdbuf==(void*)-1) {
ms_error("Could not mmap: %s",strerror(errno));
s->mmapdbuf=NULL;
return -1;
}
}
/* initialize the mediastreamer buffers */
ms_message("Using %i-frames mmap'd buffer at %p, len %i",
s->frame_max, s->mmapdbuf,s->msize);
for(i=0;i<s->frame_max;i++){
mblk_t *buf=esballoc((uint8_t*)s->mmapdbuf+vmbuf.offsets[i],vmbuf.offsets[1],0,NULL);
/* adjust to real size of picture*/
if (s->pix_fmt==MS_RGB24)
buf->b_wptr+=s->vsize.width*s->vsize.height*3;
else
buf->b_wptr+=(s->vsize.width*s->vsize.height*3)/2;
s->frames[i]=ms_yuv_buf_alloc_from_buffer(s->vsize.width, s->vsize.height, buf);
}
s->frame_ind=0;
return 0;
}
static int msv4l2_do_mmap(V4l2State *s){
struct v4l2_requestbuffers req;
int i;
enum v4l2_buf_type type;
memset(&req,0,sizeof(req));
req.count = 4;
req.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
req.memory = V4L2_MEMORY_MMAP;
if (v4l2_ioctl (s->fd, VIDIOC_REQBUFS, &req)<0) {
ms_error("Error requesting info on mmap'd buffers: %s",strerror(errno));
return -1;
}
for (i=0; i<req.count; ++i) {
struct v4l2_buffer buf;
mblk_t *msg;
void *start;
memset(&buf,0,sizeof(buf));
buf.type=V4L2_BUF_TYPE_VIDEO_CAPTURE;
buf.memory=V4L2_MEMORY_MMAP;
buf.index=i;
if (v4l2_ioctl (s->fd, VIDIOC_QUERYBUF, &buf)<0){
ms_error("Could not VIDIOC_QUERYBUF : %s",strerror(errno));
return -1;
}
start=v4l2_mmap (NULL /* start anywhere */,
buf.length,
PROT_READ | PROT_WRITE /* required */,
MAP_SHARED /* recommended */,
s->fd, buf.m.offset);
if (start==NULL){
ms_error("Could not v4l2_mmap: %s",strerror(errno));
}
msg=esballoc(start,buf.length,0,NULL);
msg->b_wptr+=buf.length;
s->frames[i]=ms_yuv_buf_alloc_from_buffer(s->vsize.width, s->vsize.height, msg);
}
s->frame_max=req.count;
for (i = 0; i < s->frame_max; ++i) {
struct v4l2_buffer buf;
memset(&buf,0,sizeof(buf));
buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
buf.memory = V4L2_MEMORY_MMAP;
buf.index = i;
if (-1==v4l2_ioctl (s->fd, VIDIOC_QBUF, &buf)){
ms_error("VIDIOC_QBUF failed: %s",strerror(errno));
}else {
inc_ref(s->frames[i]);
s->queued++;
}
}
/*start capture immediately*/
type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
if (-1 ==v4l2_ioctl (s->fd, VIDIOC_STREAMON, &type)){
ms_error("VIDIOC_STREAMON failed: %s",strerror(errno));
return -1;
}
return 0;
}
