/* * Linux DV1394 interface * Copyright (c) 2003 Max Krasnyansky <maxk@qualcomm.com> * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser 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 * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser 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 */#include <unistd.h>#include <fcntl.h>#include <errno.h>#include <sys/ioctl.h>#include <sys/mman.h>#include <sys/poll.h>#include <sys/time.h>#include <time.h>#include "avformat.h"#undef DV1394_DEBUG#include "dv1394.h"#include "dv.h"struct dv1394_data {    int fd;    int channel;    int format;    void *ring; /* Ring buffer */    int index;  /* Current frame index */    int avail;  /* Number of frames available for reading */    int done;   /* Number of completed frames */    DVDemuxContext* dv_demux; /* Generic DV muxing/demuxing context */};/*  * The trick here is to kludge around well known problem with kernel Ooopsing * when you try to capture PAL on a device node configure for NTSC. That's  * why we have to configure the device node for PAL, and then read only NTSC * amount of data. */static int dv1394_reset(struct dv1394_data *dv){    struct dv1394_init init;    init.channel     = dv->channel;    init.api_version = DV1394_API_VERSION;    init.n_frames    = DV1394_RING_FRAMES;    init.format      = DV1394_PAL;    if (ioctl(dv->fd, DV1394_INIT, &init) < 0)        return -1;    dv->avail  = dv->done = 0;    return 0;}static int dv1394_start(struct dv1394_data *dv){    /* Tell DV1394 driver to enable receiver */    if (ioctl(dv->fd, DV1394_START_RECEIVE, 0) < 0) {        perror("Failed to start receiver");        return -1;    }    return 0;}static int dv1394_read_header(AVFormatContext * context, AVFormatParameters * ap){    struct dv1394_data *dv = context->priv_data;    const char *video_device;    dv->dv_demux = dv_init_demux(context);    if (!dv->dv_demux)        goto failed;    if (ap->standard && !strcasecmp(ap->standard, "pal"))	dv->format = DV1394_PAL;    else	dv->format = DV1394_NTSC;    if (ap->channel)        dv->channel = ap->channel;    else        dv->channel = DV1394_DEFAULT_CHANNEL;    /* Open and initialize DV1394 device */    video_device = ap->device;    if (!video_device)        video_device = "/dev/dv1394/0";    dv->fd = open(video_device, O_RDONLY);    if (dv->fd < 0) {        perror("Failed to open DV interface");        goto failed;    }    if (dv1394_reset(dv) < 0) {        perror("Failed to initialize DV interface");        goto failed;    }    dv->ring = mmap(NULL, DV1394_PAL_FRAME_SIZE * DV1394_RING_FRAMES,                    PROT_READ, MAP_PRIVATE, dv->fd, 0);    if (dv->ring == MAP_FAILED) {        perror("Failed to mmap DV ring buffer");        goto failed;    }    if (dv1394_start(dv) < 0)        goto failed;    return 0;failed:    close(dv->fd);    return -EIO;}static int dv1394_read_packet(AVFormatContext *context, AVPacket *pkt){    struct dv1394_data *dv = context->priv_data;    int size;    size = dv_get_packet(dv->dv_demux, pkt);    if (size > 0)        return size;    if (!dv->avail) {        struct dv1394_status s;        struct pollfd p;        if (dv->done) {            /* Request more frames */            if (ioctl(dv->fd, DV1394_RECEIVE_FRAMES, dv->done) < 0) {                /* This usually means that ring buffer overflowed.                 * We have to reset :(.                 */                  av_log(context, AV_LOG_ERROR, "DV1394: Ring buffer overflow. Reseting ..\n");                 dv1394_reset(dv);                dv1394_start(dv);            }            dv->done = 0;        }        /* Wait until more frames are available */restart_poll:        p.fd = dv->fd;        p.events = POLLIN | POLLERR | POLLHUP;        if (poll(&p, 1, -1) < 0) {            if (errno == EAGAIN || errno == EINTR)                goto restart_poll;            perror("Poll failed");            return -EIO;        }        if (ioctl(dv->fd, DV1394_GET_STATUS, &s) < 0) {            perror("Failed to get status");            return -EIO;        }#ifdef DV1394_DEBUG        fprintf(stderr, "DV1394: status\n"                "\tactive_frame\t%d\n"                "\tfirst_clear_frame\t%d\n"                "\tn_clear_frames\t%d\n"                "\tdropped_frames\t%d\n",                s.active_frame, s.first_clear_frame,                s.n_clear_frames, s.dropped_frames);#endif        dv->avail = s.n_clear_frames;        dv->index = s.first_clear_frame;        dv->done  = 0;        if (s.dropped_frames) {            av_log(context, AV_LOG_ERROR, "DV1394: Frame drop detected (%d). Reseting ..\n",                    s.dropped_frames);            dv1394_reset(dv);            dv1394_start(dv);        }    }#ifdef DV1394_DEBUG    fprintf(stderr, "index %d, avail %d, done %d\n", dv->index, dv->avail,            dv->done);#endif    size = dv_produce_packet(dv->dv_demux, pkt,                              dv->ring + (dv->index * DV1394_PAL_FRAME_SIZE), 			     DV1394_PAL_FRAME_SIZE);    dv->index = (dv->index + 1) % DV1394_RING_FRAMES;    dv->done++; dv->avail--;        return size;}static int dv1394_close(AVFormatContext * context){    struct dv1394_data *dv = context->priv_data;    /* Shutdown DV1394 receiver */    if (ioctl(dv->fd, DV1394_SHUTDOWN, 0) < 0)        perror("Failed to shutdown DV1394");    /* Unmap ring buffer */    if (munmap(dv->ring, DV1394_NTSC_FRAME_SIZE * DV1394_RING_FRAMES) < 0)        perror("Failed to munmap DV1394 ring buffer");    close(dv->fd);    av_free(dv->dv_demux);    return 0;}static AVInputFormat dv1394_format = {    .name           = "dv1394",    .long_name      = "dv1394 A/V grab",    .priv_data_size = sizeof(struct dv1394_data),    .read_header    = dv1394_read_header,    .read_packet    = dv1394_read_packet,    .read_close     = dv1394_close,    .flags          = AVFMT_NOFILE};int dv1394_init(void){    av_register_input_format(&dv1394_format);    return 0;}