text: /* GStreamer
   *
   * Copyright (C) 2001-2002 Ronald Bultje <rbultje@ronald.bitfreak.net>
   *               2006 Edgard Lima <edgard.lima@gmail.com>
   *
   * gstv4l2.c: plugin for v4l2 elements
   *
   * This library is free software; you can redistribute it and/or
   * modify it under the terms of the GNU Library General Public
   * License as published by the Free Software Foundation; either
   * version 2 of the License, or (at your option) any later version.
   *
   * This library 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
   * Library General Public License for more details.
   *
   * You should have received a copy of the GNU Library General Public
   * License along with this library; if not, write to the
   * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
   * Boston, MA 02110-1301, USA.
   */
  
  #ifdef HAVE_CONFIG_H
  #include "config.h"
  #endif
  
  #ifndef _GNU_SOURCE
  # define _GNU_SOURCE            /* O_CLOEXEC */
  #endif
  
  #include "gst/gst-i18n-plugin.h"
  
  #include <gst/gst.h>
  
  #include <fcntl.h>
  #include <string.h>
  #include <sys/stat.h>
  #include <sys/types.h>
  #include <unistd.h>
  
  #include "ext/videodev2.h"
  #include "v4l2-utils.h"
  
  #include "gstv4l2object.h"
  #include "gstv4l2src.h"
  #include "gstv4l2sink.h"
  #include "gstv4l2radio.h"
  #include "gstv4l2videodec.h"
  #include "gstv4l2fwhtenc.h"
  #include "gstv4l2h263enc.h"
  #include "gstv4l2h264enc.h"
  #include "gstv4l2h265enc.h"
  #include "gstv4l2jpegenc.h"
  #include "gstv4l2mpeg4enc.h"
  #include "gstv4l2vp8enc.h"
  #include "gstv4l2vp9enc.h"
  #include "gstv4l2deviceprovider.h"
  #include "gstv4l2transform.h"
  
  /* used in gstv4l2object.c and v4l2_calls.c */
  GST_DEBUG_CATEGORY (v4l2_debug);
  #define GST_CAT_DEFAULT v4l2_debug
  
  #ifdef GST_V4L2_ENABLE_PROBE
  /* This is a minimalist probe, for speed, we only enumerate formats */
  static GstCaps *
  gst_v4l2_probe_template_caps (const gchar * device, gint video_fd,
      enum v4l2_buf_type type)
  {
    gint n;
    struct v4l2_fmtdesc format;
    GstCaps *caps;
  
    GST_DEBUG ("Getting %s format enumerations", device);
    caps = gst_caps_new_empty ();
  
    for (n = 0;; n++) {
      GstStructure *template;
  
      memset (&format, 0, sizeof (format));
  
      format.index = n;
      format.type = type;
  
      if (ioctl (video_fd, VIDIOC_ENUM_FMT, &format) < 0)
        break;                    /* end of enumeration */
  
      GST_LOG ("index:       %u", format.index);
      GST_LOG ("type:        %d", format.type);
      GST_LOG ("flags:       %08x", format.flags);
      GST_LOG ("description: '%s'", format.description);
      GST_LOG ("pixelformat: %" GST_FOURCC_FORMAT,
          GST_FOURCC_ARGS (format.pixelformat));
  
      template = gst_v4l2_object_v4l2fourcc_to_structure (format.pixelformat);
  
      if (template) {
        GstStructure *alt_t = NULL;
  
        switch (format.pixelformat) {
          case V4L2_PIX_FMT_RGB32:
            alt_t = gst_structure_copy (template);
            gst_structure_set (alt_t, "format", G_TYPE_STRING, "ARGB", NULL);
            break;
          case V4L2_PIX_FMT_BGR32:
            alt_t = gst_structure_copy (template);
            gst_structure_set (alt_t, "format", G_TYPE_STRING, "BGRA", NULL);
          default:
            break;
        }
  
        gst_caps_append_structure (caps, template);
  
        if (alt_t)
          gst_caps_append_structure (caps, alt_t);
      }
    }
  
    return gst_caps_simplify (caps);
  }
  
  static gboolean
  gst_v4l2_probe_and_register (GstPlugin * plugin)
  {
    GstV4l2Iterator *it;
    gint video_fd = -1;
    struct v4l2_capability vcap;
    guint32 device_caps;
  
    GST_DEBUG ("Probing devices");
  
    it = gst_v4l2_iterator_new ();
  
    while (gst_v4l2_iterator_next (it)) {
      GstCaps *src_caps, *sink_caps;
      gchar *basename;
  
      if (video_fd >= 0)
        close (video_fd);
  
      video_fd = open (it->device_path, O_RDWR | O_CLOEXEC);
  
      if (video_fd == -1) {
        GST_DEBUG ("Failed to open %s: %s", it->device_path, g_strerror (errno));
        continue;
      }
  
      memset (&vcap, 0, sizeof (vcap));
  
      if (ioctl (video_fd, VIDIOC_QUERYCAP, &vcap) < 0) {
        GST_DEBUG ("Failed to get device capabilities: %s", g_strerror (errno));
        continue;
      }
  
      if (vcap.capabilities & V4L2_CAP_DEVICE_CAPS)
        device_caps = vcap.device_caps;
      else
        device_caps = vcap.capabilities;
  
      if (!GST_V4L2_IS_M2M (device_caps))
        continue;
  
      GST_DEBUG ("Probing '%s' located at '%s'",
          it->device_name ? it->device_name : (const gchar *) vcap.driver,
          it->device_path);
  
      /* get sink supported format (no MPLANE for codec) */
      sink_caps = gst_caps_merge (gst_v4l2_probe_template_caps (it->device_path,
              video_fd, V4L2_BUF_TYPE_VIDEO_OUTPUT),
          gst_v4l2_probe_template_caps (it->device_path, video_fd,
              V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE));
  
      /* get src supported format */
      src_caps = gst_caps_merge (gst_v4l2_probe_template_caps (it->device_path,
              video_fd, V4L2_BUF_TYPE_VIDEO_CAPTURE),
          gst_v4l2_probe_template_caps (it->device_path, video_fd,
              V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE));
  
      /* Skip devices without any supported formats */
      if (gst_caps_is_empty (sink_caps) || gst_caps_is_empty (src_caps)) {
        gst_caps_unref (sink_caps);
        gst_caps_unref (src_caps);
        continue;
      }
  
      basename = g_path_get_basename (it->device_path);
  
      /* Caps won't be freed if the subclass is not instantiated */
      GST_MINI_OBJECT_FLAG_SET (sink_caps, GST_MINI_OBJECT_FLAG_MAY_BE_LEAKED);
      GST_MINI_OBJECT_FLAG_SET (src_caps, GST_MINI_OBJECT_FLAG_MAY_BE_LEAKED);
  
      if (gst_v4l2_is_video_dec (sink_caps, src_caps)) {
        gst_v4l2_video_dec_register (plugin, basename, it->device_path,
            video_fd, sink_caps, src_caps);
      } else if (gst_v4l2_is_video_enc (sink_caps, src_caps, NULL)) {
        if (gst_v4l2_is_fwht_enc (sink_caps, src_caps))
          gst_v4l2_fwht_enc_register (plugin, basename, it->device_path,
              sink_caps, src_caps);
  
        if (gst_v4l2_is_h264_enc (sink_caps, src_caps))
          gst_v4l2_h264_enc_register (plugin, basename, it->device_path,
              video_fd, sink_caps, src_caps);
  
        if (gst_v4l2_is_h265_enc (sink_caps, src_caps))
          gst_v4l2_h265_enc_register (plugin, basename, it->device_path,
              video_fd, sink_caps, src_caps);
  
        if (gst_v4l2_is_mpeg4_enc (sink_caps, src_caps))
          gst_v4l2_mpeg4_enc_register (plugin, basename, it->device_path,
              video_fd, sink_caps, src_caps);
  
        if (gst_v4l2_is_h263_enc (sink_caps, src_caps))
          gst_v4l2_h263_enc_register (plugin, basename, it->device_path,
              sink_caps, src_caps);
  
        if (gst_v4l2_is_jpeg_enc (sink_caps, src_caps))
          gst_v4l2_jpeg_enc_register (plugin, basename, it->device_path,
              sink_caps, src_caps);
  
        if (gst_v4l2_is_vp8_enc (sink_caps, src_caps))
          gst_v4l2_vp8_enc_register (plugin, basename, it->device_path,
              video_fd, sink_caps, src_caps);
  
        if (gst_v4l2_is_vp9_enc (sink_caps, src_caps))
          gst_v4l2_vp9_enc_register (plugin, basename, it->device_path,
              video_fd, sink_caps, src_caps);
      } else if (gst_v4l2_is_transform (sink_caps, src_caps)) {
        gst_v4l2_transform_register (plugin, basename, it->device_path,
            sink_caps, src_caps);
      }
      /* else if ( ... etc. */
  
      gst_caps_unref (sink_caps);
      gst_caps_unref (src_caps);
      g_free (basename);
    }
  
    if (video_fd >= 0)
      close (video_fd);
  
    gst_v4l2_iterator_free (it);
  
    return TRUE;
  }
  #endif
  
  static gboolean
  plugin_init (GstPlugin * plugin)
  {
    const gchar *paths[] = { "/dev", "/dev/v4l2", NULL };
    const gchar *names[] = { "video", NULL };
  
    GST_DEBUG_CATEGORY_INIT (v4l2_debug, "v4l2", 0, "V4L2 API calls");
  
    /* Add some dependency, so the dynamic features get updated upon changes in
     * /dev/video* */
    gst_plugin_add_dependency (plugin,
        NULL, paths, names, GST_PLUGIN_DEPENDENCY_FLAG_FILE_NAME_IS_PREFIX);
  
    if (!gst_element_register (plugin, "v4l2src", GST_RANK_PRIMARY,
            GST_TYPE_V4L2SRC) ||
        !gst_element_register (plugin, "v4l2sink", GST_RANK_NONE,
            GST_TYPE_V4L2SINK) ||
        !gst_element_register (plugin, "v4l2radio", GST_RANK_NONE,
            GST_TYPE_V4L2RADIO) ||
        !gst_device_provider_register (plugin, "v4l2deviceprovider",
            GST_RANK_PRIMARY, GST_TYPE_V4L2_DEVICE_PROVIDER)
        /* etc. */
  #ifdef GST_V4L2_ENABLE_PROBE
        || !gst_v4l2_probe_and_register (plugin)
  #endif
        )
      return FALSE;
  
  #ifdef ENABLE_NLS
    bindtextdomain (GETTEXT_PACKAGE, LOCALEDIR);
    bind_textdomain_codeset (GETTEXT_PACKAGE, "UTF-8");
  #endif /* ENABLE_NLS */
  
    return TRUE;
  }
  
  GST_PLUGIN_DEFINE (GST_VERSION_MAJOR,
      GST_VERSION_MINOR,
      video4linux2,
      "elements for Video 4 Linux",
      plugin_init, VERSION, GST_LICENSE, GST_PACKAGE_NAME, GST_PACKAGE_ORIGIN)
  