2 * Copyright (C) 2006-2009 Andre Noll <maan@systemlinux.org>
4 * Licensed under the GPL v2. For licencing details see COPYING.
8 * \file grab_client.c Functions for grabbing the stream at any position
11 * \sa filter_chain filter_chain_info filter.
15 #include <sys/types.h>
23 #include "buffer_tree.h"
25 #include "grab_client.h"
31 /** Grab clients that are not yet attached any btr node. */
32 static struct list_head inactive_grab_client_list;
34 /** Grab clients that are attached to a btr node. */
35 static struct list_head active_grab_client_list;
37 static int gc_write(struct grab_client *gc, char *buf, size_t len)
39 int ret = write_ok(gc->fd);
43 if (ret == 0) { /* fd not ready */
44 if (gc->mode == GM_PEDANTIC)
46 if (gc->mode == GM_SLOPPY)
49 ret = write_nonblock(gc->fd, buf, len, 0);
55 if (gc->mode == GM_PEDANTIC)
57 if (gc->mode == GM_SLOPPY)
65 static void gc_pre_select(struct sched *s, struct task *t)
67 struct grab_client *gc = container_of(t, struct grab_client, task);
68 int ret = btr_node_status(gc->btrn, 0, BTR_NT_LEAF);
73 s->timeout.tv_sec = 0;
74 s->timeout.tv_usec = 0;
77 para_fd_set(gc->fd, &s->wfds, &s->max_fileno);
81 * We need this forward declaration as post_select() needs
82 * activate_grab_client and vice versa.
84 static void gc_post_select(struct sched *s, struct task *t);
87 * Move a grab client to the active list and start it.
89 * \param gc The grab client to activate.
92 static void activate_grab_client(struct grab_client *gc)
94 struct btr_node *root = audiod_get_btr_root(), *parent;
98 parent = btr_search_node(gc->parent, root);
101 PARA_INFO_LOG("activating %p (fd %d)\n", gc, gc->fd);
102 list_move(&gc->node, &active_grab_client_list);
103 gc->btrn = btr_new_node("grab", parent, NULL, NULL);
104 if (!gc->task.pre_select) {
105 gc->task.pre_select = gc_pre_select;
106 gc->task.post_select = gc_post_select;
107 sprintf(gc->task.status, "grab");
108 register_task(&gc->task);
113 * Activate inactive grab clients if possible.
115 * This is called from audiod.c when the current audio file changes. It loops
116 * over all inactive grab clients and checks each grab client's configuration
117 * to determine if the client in question wishes to grab the new stream. If
118 * yes, this grab client is moved from the inactive to the active grab client list.
120 void activate_grab_clients(void)
122 struct grab_client *gc, *tmp;
124 list_for_each_entry_safe(gc, tmp, &inactive_grab_client_list, node) {
125 if (gc->task.error == -E_TASK_UNREGISTERED) {
130 activate_grab_client(gc);
134 static void add_inactive_gc(struct grab_client *gc)
136 PARA_INFO_LOG("adding grab client %p (fd %d) to inactive list\n",
138 para_list_add(&gc->node, &inactive_grab_client_list);
141 static int gc_close(struct grab_client *gc, int err)
143 btr_remove_node(gc->btrn);
144 btr_free_node(gc->btrn);
146 PARA_INFO_LOG("closing gc: %s\n", para_strerror(-err));
147 list_move(&gc->node, &inactive_grab_client_list);
148 if (err == -E_GC_WRITE || (gc->flags & GF_ONE_SHOT)) {
153 activate_grab_client(gc);
157 static void gc_post_select(__a_unused struct sched *s, struct task *t)
159 struct grab_client *gc = container_of(t, struct grab_client, task);
160 struct btr_node *btrn = gc->btrn;
166 ret = btr_node_status(btrn, 0, BTR_NT_LEAF);
171 sz = btr_next_buffer(btrn, &buf);
173 ret = gc_write(gc, buf, sz);
177 btr_consume(btrn, ret);
180 t->error = gc_close(gc, ret)? ret : 0;
183 static int check_gc_args(int argc, char **argv, struct grab_client *gc)
187 for (i = 1; i < argc; i++) {
188 const char *arg = argv[i];
191 if (!strcmp(arg, "--")) {
195 if (!strncmp(arg, "-m", 2)) {
200 gc->mode = GM_SLOPPY;
203 gc->mode = GM_AGGRESSIVE;
206 gc->mode = GM_PEDANTIC;
212 if (!strcmp(arg, "-o")) {
213 gc->flags |= GF_ONE_SHOT;
216 if (!strncmp(arg, "-p=", 3)) {
217 gc->parent = para_strdup(arg + 3);
228 * Check the command line options and allocate a grab_client structure.
230 * \param fd The file descriptor of the client.
231 * \param argc Argument count.
232 * \param argv Argument vector.
234 * If the command line options given by \a argc and \a argv are valid.
235 * allocate a struct grab_client and initialize it with this valid
236 * configuration. Moreover, add the new grab client to the inactive list.
240 * \sa grab_client, inactive_grab_client_list, activate_grab_client,
241 * filter_node::callbacks.
243 int grab_client_new(int fd, int argc, char **argv)
246 struct grab_client *gc = para_calloc(sizeof(struct grab_client));
248 ret = check_gc_args(argc, argv, gc);
253 activate_grab_client(gc);
261 * Initialize the grabbing subsystem.
263 * This has to be called once during startup before any other function from
264 * grab_client.c may be used. It initializes \a inactive_grab_client_list.
266 void init_grabbing(void)
268 PARA_INFO_LOG("grab init\n");
269 INIT_LIST_HEAD(&inactive_grab_client_list);
270 INIT_LIST_HEAD(&active_grab_client_list);