853dfba27bab85725c7fb511a4da5fd5abf73506
[paraslash.git] / grab_client.c
1 /*
2 * Copyright (C) 2006-2009 Andre Noll <maan@systemlinux.org>
3 *
4 * Licensed under the GPL v2. For licencing details see COPYING.
5 */
6
7 /**
8 * \file grab_client.c Functions for grabbing the stream at any position
9 * in a filter chain.
10 *
11 * \sa filter_chain filter_chain_info filter.
12 */
13
14 #include <regex.h>
15 #include <sys/types.h>
16 #include <dirent.h>
17 #include <stdbool.h>
18
19 #include "para.h"
20 #include "list.h"
21 #include "sched.h"
22 #include "ggo.h"
23 #include "buffer_tree.h"
24 #include "filter.h"
25 #include "grab_client.h"
26 #include "audiod.h"
27 #include "error.h"
28 #include "string.h"
29 #include "fd.h"
30
31 /** Grab clients that are not yet attached to a filter node. */
32 static struct list_head inactive_grab_client_list;
33
34 static int max_num_filters(void)
35 {
36 int i, ret = 0;
37
38 for (i = 0; audio_formats[i]; i++) {
39 PARA_INFO_LOG("%s filter chain length: %d\n", audio_formats[i],
40 num_filters(i));
41 ret = PARA_MAX(ret, num_filters(i));
42 }
43 PARA_INFO_LOG("maximal filter chain length: %d\n", ret);
44 return ret;
45 }
46
47 static struct filter_node *find_filter_node(int format, int filternum)
48 {
49 int i;
50
51 FOR_EACH_SLOT(i) {
52 struct slot_info *s = &slot[i];
53 if (s->format < 0 || !s->fc)
54 continue;
55 if (format >= 0 && s->format != format)
56 continue;
57 if (num_filters(i) <= filternum)
58 continue;
59 /* success */
60 return s->fc->filter_nodes + filternum;
61 }
62 return NULL;
63 }
64
65 static int gc_write(char *buf, size_t len, struct filter_callback *fcb)
66 {
67 struct grab_client *gc = container_of(fcb, struct grab_client, fcb);
68 size_t written = 0;
69
70 while (written < len) {
71 int ret = write_ok(gc->fd);
72 if (ret < 0)
73 goto err;
74 if (ret == 0) { /* fd not ready */
75 if (gc->mode == GM_PEDANTIC)
76 goto err;
77 if (gc->mode == GM_SLOPPY)
78 return 1;
79 }
80 ret = write(gc->fd, buf + written, len - written);
81 if (ret < 0) {
82 if (errno != EAGAIN && errno != EINTR)
83 goto err;
84 if (gc->mode == GM_PEDANTIC)
85 goto err;
86 if (gc->mode == GM_SLOPPY)
87 return 1;
88 } else
89 written += ret;
90 }
91 return 1;
92 err:
93 gc->error = -E_GC_WRITE;
94 return -E_GC_WRITE;
95 }
96
97 static void add_inactive_gc(struct grab_client *gc)
98 {
99 PARA_INFO_LOG("adding grab client %p (fd %d) to inactive list\n",
100 gc, gc->fd);
101 para_list_add(&gc->node, &inactive_grab_client_list);
102 }
103
104 static void gc_close(struct filter_callback *fcb)
105 {
106 struct grab_client *gc = container_of(fcb, struct grab_client, fcb);
107
108 if ((gc->flags & GF_ONE_SHOT) || gc->error < 0) {
109 PARA_INFO_LOG("closing fd %d (grab client %p)\n", gc->fd, gc);
110 close(gc->fd);
111 free(gc);
112 return;
113 }
114 add_inactive_gc(gc);
115 }
116
117 /**
118 * Move a grab client from the inactive list to a filter node.
119 *
120 * \param gc The grab client to activate.
121 * \param fn The filter node \a gc gets attached to.
122 *
123 * \sa filter_node::callbacks, inactive_grab_client_list.
124 */
125 void activate_grab_client(struct grab_client *gc, struct filter_node *fn)
126 {
127 PARA_INFO_LOG("activating %p (fd %d, filter node: %p)\n", gc, gc->fd, fn);
128 list_del(&gc->node);
129 para_list_add(&gc->fcb.node, &fn->callbacks);
130 }
131
132 /**
133 * Activate inactive grab clients if possible.
134 *
135 * \param audio_format_num The number of the audio format of the new audio file.
136 * \param fc The filter chain containing the activated filters.
137 *
138 * This is called from audiod.c when the current audio file changes. It loops
139 * over all inactive grab clients and checks each grab client's configuration
140 * to determine if the client in question wishes to grab the new stream. If
141 * yes, this grab client is moved from the inactive grab client list to an
142 * appropriate filter_node.
143 *
144 * \sa filter_chain_info::filters, inactive_grab_client_list,
145 * activate_grab_client.
146 */
147 void activate_inactive_grab_clients(int audio_format_num,
148 struct filter_chain *fc)
149 {
150 struct grab_client *gc, *tmp;
151 struct filter_node *fn;
152
153 list_for_each_entry_safe(gc, tmp, &inactive_grab_client_list, node) {
154 if (gc->audio_format_num >= 0 && gc->audio_format_num !=
155 audio_format_num)
156 continue;
157 if (gc->filter_num >= num_filters(audio_format_num))
158 continue;
159 fn = fc->filter_nodes + gc->filter_num;
160 activate_grab_client(gc, fn);
161 }
162 }
163
164 static int check_gc_args(int argc, char **argv, struct grab_client *gc)
165 {
166 int i, ret;
167
168 gc->audio_format_num = -1; /* default: grab any audio format */
169 for (i = 1; i < argc; i++) {
170 const char *arg = argv[i];
171 if (arg[0] != '-')
172 break;
173 if (!strcmp(arg, "--")) {
174 i++;
175 break;
176 }
177 if (!strncmp(arg, "-n=", 3)) {
178 ret = para_atoi32(arg + 3, &gc->filter_num);
179 if (ret < 0)
180 return ret;
181 if (gc->filter_num < 0)
182 return -E_BAD_GC_FILTER_NUM;
183 if (gc->filter_num >= max_num_filters())
184 return -E_BAD_GC_FILTER_NUM;
185 continue;
186 }
187 if (!strncmp(arg, "-m", 2)) {
188 if (*(arg + 3))
189 return -E_GC_SYNTAX;
190 switch(*(arg + 2)) {
191 case 's':
192 gc->mode = GM_SLOPPY;
193 continue;
194 case 'a':
195 gc->mode = GM_AGGRESSIVE;
196 continue;
197 case 'p':
198 gc->mode = GM_PEDANTIC;
199 continue;
200 default:
201 return -E_GC_SYNTAX;
202 }
203 }
204 if (!strcmp(arg, "-i")) {
205 gc->flags |= GF_INPUT_GRAB;
206 continue;
207 }
208 if (!strcmp(arg, "-o")) {
209 gc->flags |= GF_ONE_SHOT;
210 continue;
211 }
212 if (!strncmp(arg, "-f=", 3)) {
213 ret = get_audio_format_num(arg + 3);
214 if (ret < 0)
215 return ret;
216 gc->audio_format_num = ret;
217 continue;
218 }
219 return -E_GC_SYNTAX;
220 }
221 if (i != argc)
222 return -E_GC_SYNTAX;
223 return 1;
224 }
225
226 /**
227 * Check the command line options and allocate a grab_client structure.
228 *
229 * \param fd The file descriptor of the client.
230 * \param argc Argument count.
231 * \param argv Argument vector.
232 *
233 * If the command line options given by \a argc and \a argv are valid.
234 * allocate a struct grab_client and initialize it with this valid
235 * configuration. Moreover, add the new grab client to the inactive list.
236 *
237 * \return Standard.
238 *
239 * \sa grab_client, inactive_grab_client_list, activate_grab_client,
240 * filter_node::callbacks.
241 */
242 int grab_client_new(int fd, int argc, char **argv)
243 {
244 int ret;
245 struct grab_client *gc = para_calloc(sizeof(struct grab_client));
246 struct filter_node *fn;
247
248 ret = check_gc_args(argc, argv, gc);
249 if (ret < 0)
250 goto err_out;
251 if (gc->flags & GF_INPUT_GRAB)
252 gc->fcb.input_cb = gc_write;
253 else
254 gc->fcb.output_cb = gc_write;
255 gc->fd = fd;
256 gc->fcb.close = gc_close;
257 fn = find_filter_node(gc->audio_format_num, gc->filter_num);
258 if (fn)
259 para_list_add(&gc->fcb.node, &fn->callbacks);
260 else
261 add_inactive_gc(gc);
262 return 1;
263 err_out:
264 free(gc);
265 return ret;
266 }
267
268 /**
269 * Initialize the grabbing subsystem.
270 *
271 * This has to be called once during startup before any other function from
272 * grab_client.c may be used. It initializes \a inactive_grab_client_list.
273 */
274 void init_grabbing(void)
275 {
276 PARA_INFO_LOG("grab init\n");
277 INIT_LIST_HEAD(&inactive_grab_client_list);
278 }