v4l2: add libv4l2 support.

Changelog

@@ -75,6 +75,7 @@ easier to use. The changes are:
 - new ffmpeg option: -map_channel
 - volume audio filter added
 - earwax audio filter added
+- libv4l2 support (--enable-libv4l2)
 
 
 version 0.8:

configure

@@ -187,6 +187,7 @@ External library support:
   --enable-libstagefright-h264  enable H.264 decoding via libstagefright [no]
   --enable-libtheora       enable Theora encoding via libtheora [no]
   --enable-libutvideo      enable Ut Video decoding via libutvideo [no]
+  --enable-libv4l2         enable libv4l2/v4l-utils [no]
   --enable-libvo-aacenc    enable AAC encoding via libvo-aacenc [no]
   --enable-libvo-amrwbenc  enable AMR-WB encoding via libvo-amrwbenc [no]
   --enable-libvorbis       enable Vorbis encoding via libvorbis,
@@ -1022,6 +1023,7 @@ CONFIG_LIST="
     libstagefright_h264
     libtheora
     libutvideo
+    libv4l2
     libvo_aacenc
     libvo_amrwbenc
     libvorbis
@@ -1568,6 +1570,7 @@ jack_indev_deps="jack_jack_h sem_timedwait"
 lavfi_indev_deps="avfilter"
 libcdio_indev_deps="libcdio"
 libdc1394_indev_deps="libdc1394"
+libv4l2_indev_deps="libv4l2"
 openal_indev_deps="openal"
 oss_indev_deps_any="soundcard_h sys_soundcard_h"
 oss_outdev_deps_any="soundcard_h sys_soundcard_h"
@@ -3055,6 +3058,7 @@ enabled libstagefright_h264  && require_cpp libstagefright_h264 "binder/ProcessS
     media/stagefright/OMXClient.h media/stagefright/OMXCodec.h" android::OMXClient -lstagefright -lmedia -lutils -lbinder
 enabled libtheora  && require  libtheora theora/theoraenc.h th_info_init -ltheoraenc -ltheoradec -logg
 enabled libutvideo    && require_cpp utvideo "stdint.h stdlib.h utvideo/utvideo.h utvideo/Codec.h" 'CCodec*' -lutvideo -lstdc++
+enabled libv4l2    && require_pkg_config libv4l2 libv4l2.h v4l2_ioctl
 enabled libvo_aacenc && require libvo_aacenc vo-aacenc/voAAC.h voGetAACEncAPI -lvo-aacenc
 enabled libvo_amrwbenc && require libvo_amrwbenc vo-amrwbenc/enc_if.h E_IF_init -lvo-amrwbenc
 enabled libvorbis  && require  libvorbis vorbis/vorbisenc.h vorbis_info_init -lvorbisenc -lvorbis -logg
@@ -3383,6 +3387,7 @@ echo "libspeex enabled          ${libspeex-no}"
 echo "libstagefright-h264 enabled    ${libstagefright_h264-no}"
 echo "libtheora enabled         ${libtheora-no}"
 echo "libutvideo enabled        ${libutvideo-no}"
+echo "libv4l2 enabled           ${libv4l2-no}"
 echo "libvo-aacenc support      ${libvo_aacenc-no}"
 echo "libvo-amrwbenc support    ${libvo_amrwbenc-no}"
 echo "libvorbis enabled         ${libvorbis-no}"

doc/indevs.texi

@@ -513,6 +513,9 @@ input device will use the frame rate value already set in the driver.
 Video4Linux support is deprecated since Linux 2.6.30, and will be
 dropped in later versions.
 
+Note that if FFmpeg is build with v4l-utils support ("--enable-libv4l2"
+option), it will always be used.
+
 Follow some usage examples of the video4linux devices with the ff*
 tools.
 @example

libavdevice/v4l2.c

@@ -52,6 +52,18 @@
 #include "libavutil/pixdesc.h"
 #include "libavutil/avstring.h"
 
+#if CONFIG_LIBV4L2
+#include <libv4l2.h>
+#else
+#define v4l2_open   open
+#define v4l2_close  close
+#define v4l2_dup    dup
+#define v4l2_ioctl  ioctl
+#define v4l2_read   read
+#define v4l2_mmap   mmap
+#define v4l2_munmap munmap
+#endif
+
 static const int desired_video_buffers = 256;
 
 enum io_method {
@@ -113,36 +125,49 @@ static int device_open(AVFormatContext *ctx, uint32_t *capabilities)
 {
     struct v4l2_capability cap;
     int fd;
+#if CONFIG_LIBV4L2
+    int fd_libv4l;
+#endif
     int res, err;
     int flags = O_RDWR;
 
     if (ctx->flags & AVFMT_FLAG_NONBLOCK) {
         flags |= O_NONBLOCK;
     }
-    fd = open(ctx->filename, flags, 0);
+    fd = v4l2_open(ctx->filename, flags, 0);
     if (fd < 0) {
         av_log(ctx, AV_LOG_ERROR, "Cannot open video device %s : %s\n",
                  ctx->filename, strerror(errno));
         return AVERROR(errno);
     }
+#if CONFIG_LIBV4L2
+    fd_libv4l = v4l2_fd_open(fd, 0);
+    if (fd < 0) {
+        err = AVERROR(errno);
+        av_log(ctx, AV_LOG_ERROR, "Cannot open video device with libv4l neither %s : %s\n",
+               ctx->filename, strerror(errno));
+        return err;
+    }
+    fd = fd_libv4l;
+#endif
 
-    res = ioctl(fd, VIDIOC_QUERYCAP, &cap);
+    res = v4l2_ioctl(fd, VIDIOC_QUERYCAP, &cap);
     // ENOIOCTLCMD definition only availble on __KERNEL__
     if (res < 0 && ((err = errno) == 515)) {
         av_log(ctx, AV_LOG_ERROR, "QUERYCAP not implemented, probably V4L device but not supporting V4L2\n");
-        close(fd);
+        v4l2_close(fd);
 
         return AVERROR(515);
     }
     if (res < 0) {
         av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QUERYCAP): %s\n",
                  strerror(errno));
-        close(fd);
+        v4l2_close(fd);
         return AVERROR(err);
     }
     if ((cap.capabilities & V4L2_CAP_VIDEO_CAPTURE) == 0) {
         av_log(ctx, AV_LOG_ERROR, "Not a video capture device\n");
-        close(fd);
+        v4l2_close(fd);
         return AVERROR(ENODEV);
     }
     *capabilities = cap.capabilities;
@@ -162,7 +187,7 @@ static int device_init(AVFormatContext *ctx, int *width, int *height, uint32_t p
     fmt.fmt.pix.height = *height;
     fmt.fmt.pix.pixelformat = pix_fmt;
     fmt.fmt.pix.field = V4L2_FIELD_INTERLACED;
-    res = ioctl(fd, VIDIOC_S_FMT, &fmt);
+    res = v4l2_ioctl(fd, VIDIOC_S_FMT, &fmt);
     if ((*width != fmt.fmt.pix.width) || (*height != fmt.fmt.pix.height)) {
         av_log(ctx, AV_LOG_INFO, "The V4L2 driver changed the video from %dx%d to %dx%d\n", *width, *height, fmt.fmt.pix.width, fmt.fmt.pix.height);
         *width = fmt.fmt.pix.width;
@@ -182,7 +207,7 @@ static int first_field(int fd)
     int res;
     v4l2_std_id std;
 
-    res = ioctl(fd, VIDIOC_G_STD, &std);
+    res = v4l2_ioctl(fd, VIDIOC_G_STD, &std);
     if (res < 0) {
         return 0;
     }
@@ -245,7 +270,7 @@ static int mmap_init(AVFormatContext *ctx)
     req.count = desired_video_buffers;
     req.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
     req.memory = V4L2_MEMORY_MMAP;
-    res = ioctl(s->fd, VIDIOC_REQBUFS, &req);
+    res = v4l2_ioctl(s->fd, VIDIOC_REQBUFS, &req);
     if (res < 0) {
         if (errno == EINVAL) {
             av_log(ctx, AV_LOG_ERROR, "Device does not support mmap\n");
@@ -278,7 +303,7 @@ static int mmap_init(AVFormatContext *ctx)
         buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
         buf.memory = V4L2_MEMORY_MMAP;
         buf.index = i;
-        res = ioctl(s->fd, VIDIOC_QUERYBUF, &buf);
+        res = v4l2_ioctl(s->fd, VIDIOC_QUERYBUF, &buf);
         if (res < 0) {
             av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QUERYBUF)\n");
             return AVERROR(errno);
@@ -290,7 +315,7 @@ static int mmap_init(AVFormatContext *ctx)
 
             return -1;
         }
-        s->buf_start[i] = mmap (NULL, buf.length,
+        s->buf_start[i] = v4l2_mmap(NULL, buf.length,
                         PROT_READ | PROT_WRITE, MAP_SHARED, s->fd, buf.m.offset);
         if (s->buf_start[i] == MAP_FAILED) {
             av_log(ctx, AV_LOG_ERROR, "mmap: %s\n", strerror(errno));
@@ -322,7 +347,7 @@ static void mmap_release_buffer(AVPacket *pkt)
     fd = buf_descriptor->fd;
     av_free(buf_descriptor);
 
-    res = ioctl(fd, VIDIOC_QBUF, &buf);
+    res = v4l2_ioctl(fd, VIDIOC_QBUF, &buf);
     if (res < 0) {
         av_log(NULL, AV_LOG_ERROR, "ioctl(VIDIOC_QBUF): %s\n", strerror(errno));
     }
@@ -341,7 +366,7 @@ static int mmap_read_frame(AVFormatContext *ctx, AVPacket *pkt)
     buf.memory = V4L2_MEMORY_MMAP;
 
     /* FIXME: Some special treatment might be needed in case of loss of signal... */
-    while ((res = ioctl(s->fd, VIDIOC_DQBUF, &buf)) < 0 && (errno == EINTR));
+    while ((res = v4l2_ioctl(s->fd, VIDIOC_DQBUF, &buf)) < 0 && (errno == EINTR));
     if (res < 0) {
         if (errno == EAGAIN) {
             pkt->size = 0;
@@ -368,7 +393,7 @@ static int mmap_read_frame(AVFormatContext *ctx, AVPacket *pkt)
          * allocate a buffer for memcopying into it
          */
         av_log(ctx, AV_LOG_ERROR, "Failed to allocate a buffer descriptor\n");
-        res = ioctl(s->fd, VIDIOC_QBUF, &buf);
+        res = v4l2_ioctl(s->fd, VIDIOC_QBUF, &buf);
 
         return AVERROR(ENOMEM);
     }
@@ -397,7 +422,7 @@ static int mmap_start(AVFormatContext *ctx)
         buf.memory = V4L2_MEMORY_MMAP;
         buf.index  = i;
 
-        res = ioctl(s->fd, VIDIOC_QBUF, &buf);
+        res = v4l2_ioctl(s->fd, VIDIOC_QBUF, &buf);
         if (res < 0) {
             av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QBUF): %s\n", strerror(errno));
             return AVERROR(errno);
@@ -405,7 +430,7 @@ static int mmap_start(AVFormatContext *ctx)
     }
 
     type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
-    res = ioctl(s->fd, VIDIOC_STREAMON, &type);
+    res = v4l2_ioctl(s->fd, VIDIOC_STREAMON, &type);
     if (res < 0) {
         av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_STREAMON): %s\n", strerror(errno));
         return AVERROR(errno);
@@ -423,9 +448,9 @@ static void mmap_close(struct video_data *s)
     /* We do not check for the result, because we could
      * not do anything about it anyway...
      */
-    ioctl(s->fd, VIDIOC_STREAMOFF, &type);
+    v4l2_ioctl(s->fd, VIDIOC_STREAMOFF, &type);
     for (i = 0; i < s->buffers; i++) {
-        munmap(s->buf_start[i], s->buf_len[i]);
+        v4l2_munmap(s->buf_start[i], s->buf_len[i]);
     }
     av_free(s->buf_start);
     av_free(s->buf_len);
@@ -450,14 +475,14 @@ static int v4l2_set_parameters(AVFormatContext *s1, AVFormatParameters *ap)
 
     /* set tv video input */
     input.index = s->channel;
-    if (ioctl(s->fd, VIDIOC_ENUMINPUT, &input) < 0) {
+    if (v4l2_ioctl(s->fd, VIDIOC_ENUMINPUT, &input) < 0) {
         av_log(s1, AV_LOG_ERROR, "The V4L2 driver ioctl enum input failed:\n");
         return AVERROR(EIO);
     }
 
     av_log(s1, AV_LOG_DEBUG, "The V4L2 driver set input_id: %d, input: %s\n",
             s->channel, input.name);
-    if (ioctl(s->fd, VIDIOC_S_INPUT, &input.index) < 0) {
+    if (v4l2_ioctl(s->fd, VIDIOC_S_INPUT, &input.index) < 0) {
         av_log(s1, AV_LOG_ERROR, "The V4L2 driver ioctl set input(%d) failed\n",
                 s->channel);
         return AVERROR(EIO);
@@ -469,7 +494,7 @@ static int v4l2_set_parameters(AVFormatContext *s1, AVFormatParameters *ap)
         /* set tv standard */
         for (i = 0;; i++) {
             standard.index = i;
-            ret = ioctl(s->fd, VIDIOC_ENUMSTD, &standard);
+            ret = v4l2_ioctl(s->fd, VIDIOC_ENUMSTD, &standard);
             if (ret < 0 || !av_strcasecmp(standard.name, s->standard))
                 break;
         }
@@ -480,7 +505,7 @@ static int v4l2_set_parameters(AVFormatContext *s1, AVFormatParameters *ap)
 
         av_log(s1, AV_LOG_DEBUG, "The V4L2 driver set standard: %s, id: %"PRIu64"\n",
                s->standard, (uint64_t)standard.id);
-        if (ioctl(s->fd, VIDIOC_S_STD, &standard.id) < 0) {
+        if (v4l2_ioctl(s->fd, VIDIOC_S_STD, &standard.id) < 0) {
             av_log(s1, AV_LOG_ERROR, "The V4L2 driver ioctl set standard(%s) failed\n",
                    s->standard);
             return AVERROR(EIO);
@@ -492,7 +517,7 @@ static int v4l2_set_parameters(AVFormatContext *s1, AVFormatParameters *ap)
                framerate_q.den, framerate_q.num);
         tpf->numerator   = framerate_q.den;
         tpf->denominator = framerate_q.num;
-        if (ioctl(s->fd, VIDIOC_S_PARM, &streamparm) != 0) {
+        if (v4l2_ioctl(s->fd, VIDIOC_S_PARM, &streamparm) != 0) {
             av_log(s1, AV_LOG_ERROR,
                    "ioctl set time per frame(%d/%d) failed\n",
                    framerate_q.den, framerate_q.num);
@@ -508,7 +533,7 @@ static int v4l2_set_parameters(AVFormatContext *s1, AVFormatParameters *ap)
         }
     } else {
         /* if timebase value is not set, read the timebase value from the driver */
-        if (ioctl(s->fd, VIDIOC_G_PARM, &streamparm) != 0) {
+        if (v4l2_ioctl(s->fd, VIDIOC_G_PARM, &streamparm) != 0) {
             av_log(s1, AV_LOG_ERROR, "ioctl(VIDIOC_G_PARM): %s\n", strerror(errno));
             return AVERROR(errno);
         }
@@ -590,7 +615,7 @@ static int v4l2_read_header(AVFormatContext *s1, AVFormatParameters *ap)
 
         av_log(s1, AV_LOG_VERBOSE, "Querying the device for the current frame size\n");
         fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
-        if (ioctl(s->fd, VIDIOC_G_FMT, &fmt) < 0) {
+        if (v4l2_ioctl(s->fd, VIDIOC_G_FMT, &fmt) < 0) {
             av_log(s1, AV_LOG_ERROR, "ioctl(VIDIOC_G_FMT): %s\n", strerror(errno));
             res = AVERROR(errno);
             goto out;
@@ -604,7 +629,7 @@ static int v4l2_read_header(AVFormatContext *s1, AVFormatParameters *ap)
     if (desired_format == 0) {
         av_log(s1, AV_LOG_ERROR, "Cannot find a proper format for "
                "codec_id %d, pix_fmt %d.\n", s1->video_codec_id, pix_fmt);
-        close(s->fd);
+        v4l2_close(s->fd);
 
         res = AVERROR(EIO);
         goto out;
@@ -629,7 +654,7 @@ static int v4l2_read_header(AVFormatContext *s1, AVFormatParameters *ap)
         res = read_init(s1);
     }
     if (res < 0) {
-        close(s->fd);
+        v4l2_close(s->fd);
         res = AVERROR(EIO);
         goto out;
     }
@@ -681,7 +706,7 @@ static int v4l2_read_close(AVFormatContext *s1)
         mmap_close(s);
     }
 
-    close(s->fd);
+    v4l2_close(s->fd);
     return 0;
 }