lavd: add list devices API

Signed-off-by: Lukasz Marek <lukasz.m.luki@gmail.com>

doc/APIchanges

@@ -15,6 +15,9 @@ libavutil:     2012-10-22
 
 API changes, most recent first:
 
+2014-02-xx - xxxxxxx - lavd 55.10.100 - avdevice.h
+  Add avdevice_list_devices() and avdevice_free_list_devices()
+
 2014-02-xx - xxxxxxx - lavu 53.3.0 - frame.h
   Add AV_FRAME_DATA_DOWNMIX_INFO value to the AVFrameSideDataType enum and
   downmix_info.h API, which identify downmix-related metadata.

libavdevice/avdevice.c

@@ -52,3 +52,44 @@ int avdevice_dev_to_app_control_message(struct AVFormatContext *s, enum AVDevToA
         return AVERROR(ENOSYS);
     return s->control_message_cb(s, type, data, data_size);
 }
+
+int avdevice_list_devices(AVFormatContext *s, AVDeviceInfoList **device_list)
+{
+    av_assert0(s);
+    av_assert0(device_list);
+    av_assert0(s->oformat || s->iformat);
+    if ((s->oformat && !s->oformat->get_device_list) ||
+        (s->iformat && !s->iformat->get_device_list)) {
+        *device_list = NULL;
+        return AVERROR(ENOSYS);
+    }
+    *device_list = av_mallocz(sizeof(AVDeviceInfoList));
+    if (!(*device_list))
+        return AVERROR(ENOMEM);
+    if (s->oformat)
+        return s->oformat->get_device_list(s, *device_list);
+    return s->iformat->get_device_list(s, *device_list);
+}
+
+void avdevice_free_list_devices(AVDeviceInfoList **device_list)
+{
+    AVDeviceInfoList *list;
+    AVDeviceInfo *dev;
+    int i;
+
+    av_assert0(device_list);
+    list = *device_list;
+    if (!list)
+        return;
+
+    for (i = 0; i < list->nb_devices; i++) {
+        dev = list->devices[i];
+        if (dev) {
+            av_free(dev->device_name);
+            av_free(dev->device_description);
+            av_free(dev);
+        }
+    }
+    av_free(list->devices);
+    av_freep(device_list);
+}

libavdevice/avdevice.h

@@ -191,4 +191,43 @@ int avdevice_dev_to_app_control_message(struct AVFormatContext *s,
                                         enum AVDevToAppMessageType type,
                                         void *data, size_t data_size);
 
+/**
+ * Structure describes basic parameters of the device.
+ */
+typedef struct AVDeviceInfo {
+    char *device_name;                   /**< device name, format depends on device */
+    char *device_description;            /**< human friendly name */
+} AVDeviceInfo;
+
+/**
+ * List of devices.
+ */
+typedef struct AVDeviceInfoList {
+    AVDeviceInfo **devices;              /**< list of autodetected devices */
+    int nb_devices;                      /**< number of autodetected devices */
+    int default_device;                  /**< index of default device or -1 if no default */
+} AVDeviceInfoList;
+
+/**
+ * List devices.
+ *
+ * Returns available device names and their parameters.
+ *
+ * @note: Some devices may accept system-dependent device names that cannot be
+ *        autodetected. The list returned by this function cannot be assumed to
+ *        be always completed.
+ *
+ * @param s                device context.
+ * @param[out] device_list list of autodetected devices.
+ * @return count of autodetected devices, negative on error.
+ */
+int avdevice_list_devices(struct AVFormatContext *s, AVDeviceInfoList **device_list);
+
+/**
+ * Convinient function to free result of avdevice_list_devices().
+ *
+ * @param devices device list to be freed.
+ */
+void avdevice_free_list_devices(AVDeviceInfoList **device_list);
+
 #endif /* AVDEVICE_AVDEVICE_H */

libavdevice/version.h

@@ -28,8 +28,8 @@
 #include "libavutil/version.h"
 
 #define LIBAVDEVICE_VERSION_MAJOR  55
-#define LIBAVDEVICE_VERSION_MINOR   9
-#define LIBAVDEVICE_VERSION_MICRO 101
+#define LIBAVDEVICE_VERSION_MINOR  10
+#define LIBAVDEVICE_VERSION_MICRO 100
 
 #define LIBAVDEVICE_VERSION_INT AV_VERSION_INT(LIBAVDEVICE_VERSION_MAJOR, \
                                                LIBAVDEVICE_VERSION_MINOR, \

libavformat/avformat.h

@@ -261,6 +261,7 @@
 
 struct AVFormatContext;
 
+struct AVDeviceInfoList;
 
 /**
  * @defgroup metadata_api Public Metadata API
@@ -523,6 +524,11 @@ typedef struct AVOutputFormat {
      */
     int (*write_uncoded_frame)(struct AVFormatContext *, int stream_index,
                                AVFrame **frame, unsigned flags);
+    /**
+     * Returns device list with it properties.
+     * @see avdevice_list_devices() for more details.
+     */
+    int (*get_device_list)(struct AVFormatContext *s, struct AVDeviceInfoList *device_list);
 } AVOutputFormat;
 /**
  * @}
@@ -651,6 +657,12 @@ typedef struct AVInputFormat {
      * Active streams are all streams that have AVStream.discard < AVDISCARD_ALL.
      */
     int (*read_seek2)(struct AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags);
+
+    /**
+     * Returns device list with it properties.
+     * @see avdevice_list_devices() for more details.
+     */
+    int (*get_device_list)(struct AVFormatContext *s, struct AVDeviceInfoList *device_list);
 } AVInputFormat;
 /**
  * @}

libavformat/version.h

@@ -30,8 +30,8 @@
 #include "libavutil/version.h"
 
 #define LIBAVFORMAT_VERSION_MAJOR 55
-#define LIBAVFORMAT_VERSION_MINOR 32
-#define LIBAVFORMAT_VERSION_MICRO 101
+#define LIBAVFORMAT_VERSION_MINOR 33
+#define LIBAVFORMAT_VERSION_MICRO 100
 
 #define LIBAVFORMAT_VERSION_INT AV_VERSION_INT(LIBAVFORMAT_VERSION_MAJOR, \
                                                LIBAVFORMAT_VERSION_MINOR, \