/* GStreamer * * Copyright (C) 2001-2002 Ronald Bultje * 2006 Edgard Lima * 2009 Texas Instruments, Inc - http://www.ti.com/ * * gstv4l2bufferpool.c V4L2 buffer pool class * * 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., 59 Temple Place - Suite 330, * Boston, MA 02111-1307, USA. */ #ifdef HAVE_CONFIG_H # include #endif #include #include #include #include "gst/video/video.h" #include #include "gstv4l2src.h" #include "gstv4l2sink.h" #include "v4l2_calls.h" #include "gst/gst-i18n-plugin.h" /* videodev2.h is not versioned and we can't easily check for the presence * of enum values at compile time, but the V4L2_CAP_VIDEO_OUTPUT_OVERLAY define * was added in the same commit as V4L2_FIELD_INTERLACED_{TB,BT} (b2787845) */ #ifndef V4L2_CAP_VIDEO_OUTPUT_OVERLAY #define V4L2_FIELD_INTERLACED_TB 8 #define V4L2_FIELD_INTERLACED_BT 9 #endif GST_DEBUG_CATEGORY_EXTERN (v4l2_debug); #define GST_CAT_DEFAULT v4l2_debug /* * GstV4l2Buffer: */ const GstMetaInfo * gst_meta_v4l2_get_info (void) { static const GstMetaInfo *meta_info = NULL; if (meta_info == NULL) { meta_info = gst_meta_register ("GstMetaV4l2", "GstMetaV4l2", sizeof (GstMetaV4l2), (GstMetaInitFunction) NULL, (GstMetaFreeFunction) NULL, (GstMetaCopyFunction) NULL, (GstMetaTransformFunction) NULL); } return meta_info; } static void gst_v4l2_buffer_dispose (GstBuffer * buffer) { GstV4l2BufferPool *pool; gboolean resuscitated = FALSE; gint index; GstMetaV4l2 *meta; GstV4l2Object *obj; meta = GST_META_V4L2_GET (buffer); g_assert (meta != NULL); pool = meta->pool; index = meta->vbuffer.index; obj = pool->obj; GST_LOG_OBJECT (obj->element, "finalizing buffer %p %d", buffer, index); GST_V4L2_BUFFER_POOL_LOCK (pool); if (pool->running) { if (pool->requeuebuf) { if (!gst_v4l2_buffer_pool_qbuf (pool, buffer)) { GST_WARNING_OBJECT (obj->element, "could not requeue buffer %p %d", buffer, index); } else { resuscitated = TRUE; } } else { resuscitated = TRUE; /* XXX double check this... I think it is ok to not synchronize this * w.r.t. destruction of the pool, since the buffer is still live and * the buffer holds a ref to the pool.. */ g_async_queue_push (pool->avail_buffers, buffer); } } else { GST_LOG_OBJECT (obj->element, "the pool is shutting down"); } if (resuscitated) { GST_LOG_OBJECT (obj->element, "reviving buffer %p, %d", buffer, index); gst_buffer_ref (buffer); pool->buffers[index] = buffer; } GST_V4L2_BUFFER_POOL_UNLOCK (pool); if (!resuscitated) { GST_LOG_OBJECT (obj->element, "buffer %p (data %p, len %u) not recovered, unmapping", buffer, meta->mem, meta->vbuffer.length); v4l2_munmap (meta->mem, meta->vbuffer.length); g_object_unref (pool); } } static GstBuffer * gst_v4l2_buffer_new (GstV4l2BufferPool * pool, guint index) { GstBuffer *ret; GstMetaV4l2 *meta; GstV4l2Object *obj; obj = pool->obj; ret = gst_buffer_new (); GST_MINI_OBJECT_CAST (ret)->dispose = (GstMiniObjectDisposeFunction) gst_v4l2_buffer_dispose; meta = GST_META_V4L2_ADD (ret); GST_LOG_OBJECT (obj->element, "creating buffer %u, %p in pool %p", index, ret, pool); meta->pool = (GstV4l2BufferPool *) g_object_ref (pool); meta->vbuffer.index = index; meta->vbuffer.type = pool->type; meta->vbuffer.memory = V4L2_MEMORY_MMAP; if (v4l2_ioctl (pool->video_fd, VIDIOC_QUERYBUF, &meta->vbuffer) < 0) goto querybuf_failed; GST_LOG_OBJECT (obj->element, " index: %u", meta->vbuffer.index); GST_LOG_OBJECT (obj->element, " type: %d", meta->vbuffer.type); GST_LOG_OBJECT (obj->element, " bytesused: %u", meta->vbuffer.bytesused); GST_LOG_OBJECT (obj->element, " flags: %08x", meta->vbuffer.flags); GST_LOG_OBJECT (obj->element, " field: %d", meta->vbuffer.field); GST_LOG_OBJECT (obj->element, " memory: %d", meta->vbuffer.memory); if (meta->vbuffer.memory == V4L2_MEMORY_MMAP) GST_LOG_OBJECT (obj->element, " MMAP offset: %u", meta->vbuffer.m.offset); GST_LOG_OBJECT (obj->element, " length: %u", meta->vbuffer.length); GST_LOG_OBJECT (obj->element, " input: %u", meta->vbuffer.input); meta->mem = v4l2_mmap (0, meta->vbuffer.length, PROT_READ | PROT_WRITE, MAP_SHARED, pool->video_fd, meta->vbuffer.m.offset); if (meta->mem == MAP_FAILED) goto mmap_failed; gst_buffer_take_memory (ret, -1, gst_memory_new_wrapped (0, meta->mem, NULL, meta->vbuffer.length, 0, meta->vbuffer.length)); /* add metadata to buffers */ return ret; /* ERRORS */ querybuf_failed: { gint errnosave = errno; GST_WARNING ("Failed QUERYBUF: %s", g_strerror (errnosave)); gst_buffer_unref (ret); errno = errnosave; return NULL; } mmap_failed: { gint errnosave = errno; GST_WARNING ("Failed to mmap: %s", g_strerror (errnosave)); gst_buffer_unref (ret); errno = errnosave; return NULL; } } /* * GstV4l2BufferPool: */ #define gst_v4l2_buffer_pool_parent_class parent_class G_DEFINE_TYPE (GstV4l2BufferPool, gst_v4l2_buffer_pool, G_TYPE_OBJECT); static void gst_v4l2_buffer_pool_finalize (GObject * object) { GstV4l2BufferPool *pool = GST_V4L2_BUFFER_POOL (object); g_mutex_free (pool->lock); pool->lock = NULL; g_async_queue_unref (pool->avail_buffers); pool->avail_buffers = NULL; if (pool->video_fd >= 0) v4l2_close (pool->video_fd); if (pool->buffers) { g_free (pool->buffers); pool->buffers = NULL; } G_OBJECT_CLASS (parent_class)->finalize (object); } static void gst_v4l2_buffer_pool_init (GstV4l2BufferPool * pool) { pool->lock = g_mutex_new (); pool->running = FALSE; pool->num_live_buffers = 0; } static void gst_v4l2_buffer_pool_class_init (GstV4l2BufferPoolClass * klass) { GObjectClass *object_class = G_OBJECT_CLASS (klass); object_class->finalize = gst_v4l2_buffer_pool_finalize; } /** * gst_v4l2_buffer_pool_new: * @obj: the v4l2 object owning the pool * @num_buffers: the requested number of buffers in the pool * @requeuebuf: if %TRUE, and if the pool is still in the running state, a * buffer with no remaining references is immediately passed back to v4l2 * (VIDIOC_QBUF), otherwise it is returned to the pool of available buffers * (which can be accessed via gst_v4l2_buffer_pool_get(). * * Construct a new buffer pool. * * Returns: the new pool, use gst_v4l2_buffer_pool_destroy() to free resources */ GstV4l2BufferPool * gst_v4l2_buffer_pool_new (GstV4l2Object * obj, gint num_buffers, gboolean requeuebuf) { GstV4l2BufferPool *pool; gint n; struct v4l2_requestbuffers breq; pool = (GstV4l2BufferPool *) g_object_new (GST_TYPE_V4L2_BUFFER_POOL, NULL); pool->video_fd = v4l2_dup (obj->video_fd); if (pool->video_fd < 0) goto dup_failed; /* first, lets request buffers, and see how many we can get: */ GST_DEBUG_OBJECT (obj->element, "STREAMING, requesting %d MMAP buffers", num_buffers); memset (&breq, 0, sizeof (struct v4l2_requestbuffers)); breq.type = obj->type; breq.count = num_buffers; breq.memory = V4L2_MEMORY_MMAP; if (v4l2_ioctl (pool->video_fd, VIDIOC_REQBUFS, &breq) < 0) goto reqbufs_failed; GST_LOG_OBJECT (obj->element, " count: %u", breq.count); GST_LOG_OBJECT (obj->element, " type: %d", breq.type); GST_LOG_OBJECT (obj->element, " memory: %d", breq.memory); if (breq.count < GST_V4L2_MIN_BUFFERS) goto no_buffers; if (num_buffers != breq.count) { GST_WARNING_OBJECT (obj->element, "using %u buffers instead", breq.count); num_buffers = breq.count; } pool->obj = obj; pool->requeuebuf = requeuebuf; pool->type = obj->type; pool->buffer_count = num_buffers; pool->buffers = g_new0 (GstBuffer *, num_buffers); pool->avail_buffers = g_async_queue_new (); /* now, map the buffers: */ for (n = 0; n < num_buffers; n++) { pool->buffers[n] = gst_v4l2_buffer_new (pool, n); if (!pool->buffers[n]) goto buffer_new_failed; pool->num_live_buffers++; g_async_queue_push (pool->avail_buffers, pool->buffers[n]); } return pool; /* ERRORS */ dup_failed: { gint errnosave = errno; g_object_unref (pool); errno = errnosave; return NULL; } reqbufs_failed: { GST_ELEMENT_ERROR (obj->element, RESOURCE, READ, (_("Could not get buffers from device '%s'."), obj->videodev), ("error requesting %d buffers: %s", num_buffers, g_strerror (errno))); return NULL; } no_buffers: { GST_ELEMENT_ERROR (obj->element, RESOURCE, READ, (_("Could not get enough buffers from device '%s'."), obj->videodev), ("we received %d from device '%s', we want at least %d", breq.count, obj->videodev, GST_V4L2_MIN_BUFFERS)); return NULL; } buffer_new_failed: { gint errnosave = errno; gst_v4l2_buffer_pool_destroy (pool); errno = errnosave; return NULL; } } /** * gst_v4l2_buffer_pool_destroy: * @pool: the pool * * Free all resources in the pool and the pool itself. */ void gst_v4l2_buffer_pool_destroy (GstV4l2BufferPool * pool) { gint n; GstV4l2Object *obj = pool->obj; GST_V4L2_BUFFER_POOL_LOCK (pool); pool->running = FALSE; GST_V4L2_BUFFER_POOL_UNLOCK (pool); GST_DEBUG_OBJECT (obj->element, "destroy pool"); /* after this point, no more buffers will be queued or dequeued; no buffer * from pool->buffers that is NULL will be set to a buffer, and no buffer that * is not NULL will be pushed out. */ /* miniobjects have no dispose, so they can't break ref-cycles, as buffers ref * the pool, we need to unref the buffer to properly finalize te pool */ for (n = 0; n < pool->buffer_count; n++) { GstBuffer *buf; GST_V4L2_BUFFER_POOL_LOCK (pool); buf = pool->buffers[n]; GST_V4L2_BUFFER_POOL_UNLOCK (pool); if (buf) /* we own the ref if the buffer is in pool->buffers; drop it. */ gst_buffer_unref (buf); } g_object_unref (pool); } /** * gst_v4l2_buffer_pool_get: * @pool: the "this" object * @blocking: should this call suspend until there is a buffer available * in the buffer pool? * * Get an available buffer in the pool */ GstBuffer * gst_v4l2_buffer_pool_get (GstV4l2BufferPool * pool, gboolean blocking) { GstBuffer *buf; if (blocking) { buf = g_async_queue_pop (pool->avail_buffers); } else { buf = g_async_queue_try_pop (pool->avail_buffers); } if (buf) { GstMetaV4l2 *meta = GST_META_V4L2_GET (buf); GST_V4L2_BUFFER_POOL_LOCK (pool); gst_buffer_resize (buf, 0, meta->vbuffer.length); GST_BUFFER_FLAG_UNSET (buf, 0xffffffff); GST_V4L2_BUFFER_POOL_UNLOCK (pool); } pool->running = TRUE; return buf; } /** * gst_v4l2_buffer_pool_qbuf: * @pool: the pool * @buf: the buffer to queue * * Queue a buffer to the driver * * Returns: %TRUE for success */ gboolean gst_v4l2_buffer_pool_qbuf (GstV4l2BufferPool * pool, GstBuffer * buf) { GstMetaV4l2 *meta; GstV4l2Object *obj = pool->obj; meta = GST_META_V4L2_GET (buf); GST_LOG_OBJECT (obj->element, "enqueue pool buffer %d", meta->vbuffer.index); if (v4l2_ioctl (pool->video_fd, VIDIOC_QBUF, &meta->vbuffer) < 0) goto queue_failed; pool->num_live_buffers--; GST_DEBUG_OBJECT (obj->element, "num_live_buffers--: %d", pool->num_live_buffers); return TRUE; /* ERRORS */ queue_failed: { GST_WARNING_OBJECT (obj->element, "could not queue a buffer"); return FALSE; } } /** * gst_v4l2_buffer_pool_dqbuf: * @pool: the pool * * Dequeue a buffer from the driver. Some generic error handling is done in * this function, but any error handling specific to v4l2src (capture) or * v4l2sink (output) can be done outside this function by checking 'errno' * * Returns: a buffer */ GstBuffer * gst_v4l2_buffer_pool_dqbuf (GstV4l2BufferPool * pool) { GstBuffer *pool_buffer; struct v4l2_buffer buffer; GstV4l2Object *obj = pool->obj; memset (&buffer, 0x00, sizeof (buffer)); buffer.type = pool->type; buffer.memory = V4L2_MEMORY_MMAP; if (v4l2_ioctl (pool->video_fd, VIDIOC_DQBUF, &buffer) < 0) goto error; GST_V4L2_BUFFER_POOL_LOCK (pool); /* get our GstBuffer with that index from the pool, if the buffer was * outstanding we have a serious problem. */ pool_buffer = pool->buffers[buffer.index]; if (pool_buffer == NULL) goto no_buffers; GST_LOG_OBJECT (obj->element, "grabbed frame %d (ix=%d), flags %08x, pool-ct=%d, buffer=%p", buffer.sequence, buffer.index, buffer.flags, pool->num_live_buffers, pool_buffer); pool->num_live_buffers++; GST_DEBUG_OBJECT (obj->element, "num_live_buffers++: %d", pool->num_live_buffers); /* set top/bottom field first if v4l2_buffer has the information */ if (buffer.field == V4L2_FIELD_INTERLACED_TB) GST_BUFFER_FLAG_SET (pool_buffer, GST_VIDEO_BUFFER_TFF); if (buffer.field == V4L2_FIELD_INTERLACED_BT) GST_BUFFER_FLAG_UNSET (pool_buffer, GST_VIDEO_BUFFER_TFF); /* this can change at every frame, esp. with jpeg */ gst_buffer_resize (pool_buffer, 0, buffer.bytesused); GST_V4L2_BUFFER_POOL_UNLOCK (pool); return pool_buffer; /* ERRORS */ error: { GST_WARNING_OBJECT (obj->element, "problem grabbing frame %d (ix=%d), pool-ct=%d, buf.flags=%d", buffer.sequence, buffer.index, GST_MINI_OBJECT_REFCOUNT (pool), buffer.flags); switch (errno) { case EAGAIN: GST_WARNING_OBJECT (obj->element, "Non-blocking I/O has been selected using O_NONBLOCK and" " no buffer was in the outgoing queue. device %s", obj->videodev); break; case EINVAL: GST_ELEMENT_ERROR (obj->element, RESOURCE, FAILED, (_("Failed trying to get video frames from device '%s'."), obj->videodev), (_("The buffer type is not supported, or the index is out of bounds," " or no buffers have been allocated yet, or the userptr" " or length are invalid. device %s"), obj->videodev)); break; case ENOMEM: GST_ELEMENT_ERROR (obj->element, RESOURCE, FAILED, (_("Failed trying to get video frames from device '%s'. Not enough memory."), obj->videodev), (_("insufficient memory to enqueue a user pointer buffer. device %s."), obj->videodev)); break; case EIO: GST_INFO_OBJECT (obj->element, "VIDIOC_DQBUF failed due to an internal error." " Can also indicate temporary problems like signal loss." " Note the driver might dequeue an (empty) buffer despite" " returning an error, or even stop capturing." " device %s", obj->videodev); /* have we de-queued a buffer ? */ if (!(buffer.flags & (V4L2_BUF_FLAG_QUEUED | V4L2_BUF_FLAG_DONE))) { GST_DEBUG_OBJECT (obj->element, "reenqueing buffer"); /* FIXME ... should we do something here? */ } break; case EINTR: GST_WARNING_OBJECT (obj->element, "could not sync on a buffer on device %s", obj->videodev); break; default: GST_WARNING_OBJECT (obj->element, "Grabbing frame got interrupted on %s unexpectedly. %d: %s.", obj->videodev, errno, g_strerror (errno)); break; } return NULL; } no_buffers: { GST_ELEMENT_ERROR (obj->element, RESOURCE, FAILED, (_("Failed trying to get video frames from device '%s'."), obj->videodev), (_("No free buffers found in the pool at index %d."), buffer.index)); GST_V4L2_BUFFER_POOL_UNLOCK (pool); return NULL; } } /** * gst_v4l2_buffer_pool_available_buffers: * @pool: the pool * * Check the number of buffers available to the driver, ie. buffers that * have been QBUF'd but not yet DQBUF'd. * * Returns: the number of buffers available. */ gint gst_v4l2_buffer_pool_available_buffers (GstV4l2BufferPool * pool) { return pool->buffer_count - pool->num_live_buffers; }