Make av_read_frame with rtsp client return EINTR on interrupt
[libav.git] / libavdevice / dv1394.c
1 /*
2 * Linux DV1394 interface
3 * Copyright (c) 2003 Max Krasnyansky <maxk@qualcomm.com>
4 *
5 * This file is part of FFmpeg.
6 *
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22 #include <unistd.h>
23 #include <fcntl.h>
24 #include <errno.h>
25 #include <sys/ioctl.h>
26 #include <sys/mman.h>
27 #include <sys/poll.h>
28 #include <sys/time.h>
29 #include <time.h>
30
31 #include "avformat.h"
32
33 #undef DV1394_DEBUG
34
35 #include "dv1394.h"
36 #include "dv.h"
37
38 struct dv1394_data {
39 int fd;
40 int channel;
41 int format;
42
43 uint8_t *ring; /* Ring buffer */
44 int index; /* Current frame index */
45 int avail; /* Number of frames available for reading */
46 int done; /* Number of completed frames */
47
48 DVDemuxContext* dv_demux; /* Generic DV muxing/demuxing context */
49 };
50
51 /*
52 * The trick here is to kludge around well known problem with kernel Ooopsing
53 * when you try to capture PAL on a device node configure for NTSC. That's
54 * why we have to configure the device node for PAL, and then read only NTSC
55 * amount of data.
56 */
57 static int dv1394_reset(struct dv1394_data *dv)
58 {
59 struct dv1394_init init;
60
61 init.channel = dv->channel;
62 init.api_version = DV1394_API_VERSION;
63 init.n_frames = DV1394_RING_FRAMES;
64 init.format = DV1394_PAL;
65
66 if (ioctl(dv->fd, DV1394_INIT, &init) < 0)
67 return -1;
68
69 dv->avail = dv->done = 0;
70 return 0;
71 }
72
73 static int dv1394_start(struct dv1394_data *dv)
74 {
75 /* Tell DV1394 driver to enable receiver */
76 if (ioctl(dv->fd, DV1394_START_RECEIVE, 0) < 0) {
77 av_log(NULL, AV_LOG_ERROR, "Failed to start receiver: %s\n", strerror(errno));
78 return -1;
79 }
80 return 0;
81 }
82
83 static int dv1394_read_header(AVFormatContext * context, AVFormatParameters * ap)
84 {
85 struct dv1394_data *dv = context->priv_data;
86
87 dv->dv_demux = dv_init_demux(context);
88 if (!dv->dv_demux)
89 goto failed;
90
91 if (ap->standard && !strcasecmp(ap->standard, "pal"))
92 dv->format = DV1394_PAL;
93 else
94 dv->format = DV1394_NTSC;
95
96 if (ap->channel)
97 dv->channel = ap->channel;
98 else
99 dv->channel = DV1394_DEFAULT_CHANNEL;
100
101 /* Open and initialize DV1394 device */
102 dv->fd = open(context->filename, O_RDONLY);
103 if (dv->fd < 0) {
104 av_log(context, AV_LOG_ERROR, "Failed to open DV interface: %s\n", strerror(errno));
105 goto failed;
106 }
107
108 if (dv1394_reset(dv) < 0) {
109 av_log(context, AV_LOG_ERROR, "Failed to initialize DV interface: %s\n", strerror(errno));
110 goto failed;
111 }
112
113 dv->ring = mmap(NULL, DV1394_PAL_FRAME_SIZE * DV1394_RING_FRAMES,
114 PROT_READ, MAP_PRIVATE, dv->fd, 0);
115 if (dv->ring == MAP_FAILED) {
116 av_log(context, AV_LOG_ERROR, "Failed to mmap DV ring buffer: %s\n", strerror(errno));
117 goto failed;
118 }
119
120 if (dv1394_start(dv) < 0)
121 goto failed;
122
123 return 0;
124
125 failed:
126 close(dv->fd);
127 return AVERROR(EIO);
128 }
129
130 static int dv1394_read_packet(AVFormatContext *context, AVPacket *pkt)
131 {
132 struct dv1394_data *dv = context->priv_data;
133 int size;
134
135 size = dv_get_packet(dv->dv_demux, pkt);
136 if (size > 0)
137 return size;
138
139 if (!dv->avail) {
140 struct dv1394_status s;
141 struct pollfd p;
142
143 if (dv->done) {
144 /* Request more frames */
145 if (ioctl(dv->fd, DV1394_RECEIVE_FRAMES, dv->done) < 0) {
146 /* This usually means that ring buffer overflowed.
147 * We have to reset :(.
148 */
149
150 av_log(context, AV_LOG_ERROR, "DV1394: Ring buffer overflow. Reseting ..\n");
151
152 dv1394_reset(dv);
153 dv1394_start(dv);
154 }
155 dv->done = 0;
156 }
157
158 /* Wait until more frames are available */
159 restart_poll:
160 p.fd = dv->fd;
161 p.events = POLLIN | POLLERR | POLLHUP;
162 if (poll(&p, 1, -1) < 0) {
163 if (errno == EAGAIN || errno == EINTR)
164 goto restart_poll;
165 av_log(context, AV_LOG_ERROR, "Poll failed: %s\n", strerror(errno));
166 return AVERROR(EIO);
167 }
168
169 if (ioctl(dv->fd, DV1394_GET_STATUS, &s) < 0) {
170 av_log(context, AV_LOG_ERROR, "Failed to get status: %s\n", strerror(errno));
171 return AVERROR(EIO);
172 }
173 #ifdef DV1394_DEBUG
174 av_log(context, AV_LOG_DEBUG, "DV1394: status\n"
175 "\tactive_frame\t%d\n"
176 "\tfirst_clear_frame\t%d\n"
177 "\tn_clear_frames\t%d\n"
178 "\tdropped_frames\t%d\n",
179 s.active_frame, s.first_clear_frame,
180 s.n_clear_frames, s.dropped_frames);
181 #endif
182
183 dv->avail = s.n_clear_frames;
184 dv->index = s.first_clear_frame;
185 dv->done = 0;
186
187 if (s.dropped_frames) {
188 av_log(context, AV_LOG_ERROR, "DV1394: Frame drop detected (%d). Reseting ..\n",
189 s.dropped_frames);
190
191 dv1394_reset(dv);
192 dv1394_start(dv);
193 }
194 }
195
196 #ifdef DV1394_DEBUG
197 av_log(context, AV_LOG_DEBUG, "index %d, avail %d, done %d\n", dv->index, dv->avail,
198 dv->done);
199 #endif
200
201 size = dv_produce_packet(dv->dv_demux, pkt,
202 dv->ring + (dv->index * DV1394_PAL_FRAME_SIZE),
203 DV1394_PAL_FRAME_SIZE);
204 dv->index = (dv->index + 1) % DV1394_RING_FRAMES;
205 dv->done++; dv->avail--;
206
207 return size;
208 }
209
210 static int dv1394_close(AVFormatContext * context)
211 {
212 struct dv1394_data *dv = context->priv_data;
213
214 /* Shutdown DV1394 receiver */
215 if (ioctl(dv->fd, DV1394_SHUTDOWN, 0) < 0)
216 av_log(context, AV_LOG_ERROR, "Failed to shutdown DV1394: %s\n", strerror(errno));
217
218 /* Unmap ring buffer */
219 if (munmap(dv->ring, DV1394_NTSC_FRAME_SIZE * DV1394_RING_FRAMES) < 0)
220 av_log(context, AV_LOG_ERROR, "Failed to munmap DV1394 ring buffer: %s\n", strerror(errno));
221
222 close(dv->fd);
223 av_free(dv->dv_demux);
224
225 return 0;
226 }
227
228 AVInputFormat dv1394_demuxer = {
229 .name = "dv1394",
230 .long_name = "dv1394 A/V grab",
231 .priv_data_size = sizeof(struct dv1394_data),
232 .read_header = dv1394_read_header,
233 .read_packet = dv1394_read_packet,
234 .read_close = dv1394_close,
235 .flags = AVFMT_NOFILE
236 };