8385ae8a86ef390a8943ca64cdf3445003e09fd4
[disorder] / driver / disorder.c
1
2 /*
3 * This file is part of DisOrder.
4 * Copyright (C) 2005 Richard Kettlewell
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful, but
12 * WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
19 * USA
20 */
21
22 #include <config.h>
23
24 #include <string.h>
25 #include <stdlib.h>
26 #include <errno.h>
27 #include <unistd.h>
28 #include <poll.h>
29 #include <ao/ao.h>
30 #include <ao/plugin.h>
31
32 /* extra declarations to help out lazy <ao/plugin.h> */
33 int ao_plugin_test(void);
34 ao_info *ao_plugin_driver_info(void);
35 char *ao_plugin_file_extension(void);
36
37 /* private data structure for this driver */
38 struct internal {
39 int fd; /* output file descriptor */
40 int exit_on_error; /* exit on write error */
41 };
42
43 /* like write() but never returns EINTR/EAGAIN or short */
44 static int do_write(int fd, const void *ptr, size_t n) {
45 size_t written = 0;
46 int ret;
47 struct pollfd ufd;
48
49 memset(&ufd, 0, sizeof ufd);
50 ufd.fd = fd;
51 ufd.events = POLLOUT;
52 while(written < n) {
53 ret = write(fd, (const char *)ptr + written, n - written);
54 if(ret < 0) {
55 switch(errno) {
56 case EINTR: break;
57 case EAGAIN:
58 /* Someone sneakily gave us a nonblocking file descriptor, wait until
59 * we can write again */
60 ret = poll(&ufd, 1, -1);
61 if(ret < 0 && errno != EINTR) return -1;
62 break;
63 default:
64 return -1;
65 }
66 } else
67 written += ret;
68 }
69 return written;
70 }
71
72 /* return 1 if this driver can be opened */
73 int ao_plugin_test(void) {
74 return 1;
75 }
76
77 /* return info about this driver */
78 ao_info *ao_plugin_driver_info(void) {
79 static const char *options[] = { "fd" };
80 static const ao_info info = {
81 AO_TYPE_LIVE, /* type */
82 (char *)"DisOrder format driver", /* name */
83 (char *)"disorder", /* short_name */
84 (char *)"http://www.greenend.org.uk/rjk/disorder/", /* comment */
85 (char *)"Richard Kettlewell", /* author */
86 AO_FMT_NATIVE, /* preferred_byte_format */
87 0, /* priority */
88 (char **)options, /* options */
89 1, /* option_count */
90 };
91 return (ao_info *)&info;
92 }
93
94 /* initialize the private data structure */
95 int ao_plugin_device_init(ao_device *device) {
96 struct internal *i = malloc(sizeof (struct internal));
97 const char *e;
98
99 if(!i) return 0;
100 memset(i, 0, sizeof *i);
101 if((e = getenv("DISORDER_RAW_FD")))
102 i->fd = atoi(e);
103 else
104 i->fd = 1;
105 device->internal = i;
106 return 1;
107 }
108
109 /* set an option */
110 int ao_plugin_set_option(ao_device *device,
111 const char *key,
112 const char *value) {
113 struct internal *i = device->internal;
114
115 if(!strcmp(key, "fd"))
116 i->fd = atoi(value);
117 else if(!strcmp(key, "fragile"))
118 i->exit_on_error = atoi(value);
119 /* unknown options are required to be ignored */
120 return 1;
121 }
122
123 /* open the device */
124 int ao_plugin_open(ao_device *device, ao_sample_format *format) {
125 struct internal *i = device->internal;
126
127 /* we would like native-order samples */
128 device->driver_byte_format = AO_FMT_NATIVE;
129 if(do_write(i->fd, format, sizeof *format) < 0) {
130 if(i->exit_on_error) exit(-1);
131 return 0;
132 }
133 return 1;
134 }
135
136 /* play some samples */
137 int ao_plugin_play(ao_device *device, const char *output_samples,
138 uint_32 num_bytes) {
139 struct internal *i = device->internal;
140
141 if(do_write(i->fd, output_samples, num_bytes) < 0) {
142 if(i->exit_on_error) _exit(-1);
143 return 0;
144 }
145 return 1;
146 }
147
148 /* close the device */
149 int ao_plugin_close(ao_device attribute((unused)) *device) {
150 return 1;
151 }
152
153 /* delete private data structures */
154 void ao_plugin_device_clear(ao_device *device) {
155 free(device->internal);
156 device->internal = 0;
157 }
158
159 /* report preferred filename extension */
160 char *ao_plugin_file_extension(void) {
161 return 0;
162 }
163
164 /*
165 Local Variables:
166 c-basic-offset:2
167 comment-column:40
168 End:
169 */
170 /* arch-tag:ru/Jqo0hseWMoSt/ba4Xlw */