b05a9e9839e8e5bf6e37531f81307cb8a08318dc
[paraslash.git] / write_common.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 /** \file write_common.c common functions of para_audiod and para_write */
8
9 #include <regex.h>
10 #include <stdbool.h>
11
12 #include "para.h"
13 #include "string.h"
14 #include "list.h"
15 #include "sched.h"
16 #include "ggo.h"
17 #include "buffer_tree.h"
18 #include "write.h"
19 #include "error.h"
20
21 /** the array containing the names of all supported writers */
22 const char *writer_names[] ={WRITER_NAMES};
23
24 /** the array of supported writers */
25 struct writer writers[NUM_SUPPORTED_WRITERS] = {WRITER_ARRAY};
26
27 /**
28 * Call the init function of each supported paraslash writer.
29 */
30 void writer_init(void)
31 {
32 int i;
33
34 FOR_EACH_WRITER(i)
35 writers[i].init(&writers[i]);
36 }
37 /**
38 * check if given string is a valid command line for any writer
39 *
40 * \param \wa string of the form writer_name:options
41 * \param writer_num contains the number of the writer upon success
42 *
43 * This function checks whether \a wa starts with the name of a supported
44 * paraslash writer, optionally followed by a colon and any options for that
45 * writer. If a valid writer name was found and further are present, the
46 * remaining part of \a wa is passed to that writer's config parser.
47 *
48 * \return On success, a pointer to the gengetopt args info struct is returned
49 * and \a writer_num contains the number of the writer. Otherwise this function
50 * returns \p NULL.
51 */
52 void *check_writer_arg(const char *wa, int *writer_num)
53 {
54 int i;
55
56 *writer_num = -E_WRITE_COMMON_SYNTAX;
57 PARA_INFO_LOG("checking %s\n", wa);
58 FOR_EACH_WRITER(i) {
59 const char *name = writer_names[i];
60 size_t len = strlen(name);
61 char c;
62 if (strlen(wa) < len)
63 continue;
64 if (strncmp(name, wa, len))
65 continue;
66 c = wa[len];
67 if (c && c != ' ')
68 continue;
69 if (c && !writers[i].parse_config)
70 return NULL;
71 *writer_num = i;
72 return writers[i].parse_config(c? wa + len + 1 : "");
73 }
74 PARA_ERROR_LOG("writer not found\n");
75 return NULL;
76 }
77
78 void register_writer_node(struct writer_node *wn, struct btr_node *parent)
79 {
80 struct writer *w = writers + wn->writer_num;
81 char *name = make_message("%s writer", writer_names[wn->writer_num]);
82 int ret;
83
84 wn->btrn = btr_new_node(name, parent, w->execute, wn);
85 strcpy(wn->task.status, name);
86 free(name);
87 ret = w->open(wn);
88 wn->task.post_select = w->post_select_btr;
89 wn->task.pre_select = w->pre_select_btr;
90 register_task(&wn->task);
91 }
92
93 /**
94 * Setup a writer node with the default writer.
95 *
96 * If arg is \p NULL, the OS-dependent default writer is used with an empty
97 * configuration string. It defaults to alsa for Linux, osx for OS X, oss for
98 * *BSD and the file writer if neither of these is supported.
99 *
100 * Once the writer configuration has been retrieved, a writer node is created,
101 * its buffer tree node is added to the buffer tree as a child of the given
102 * parent.
103 *
104 * Finally, the new writer node's taks structure is initialized and registered
105 * to the paraslash scheduler.
106 *
107 * \return A pointer to the allocated writer node group.
108 */
109 int setup_writer_node(const char *arg, struct btr_node *parent,
110 struct writer_node *wn)
111 {
112 if (arg)
113 wn->conf = check_writer_arg(arg, &wn->writer_num);
114 else {
115 wn->writer_num = DEFAULT_WRITER;
116 wn->conf = writers[DEFAULT_WRITER].parse_config("");
117 }
118 if (!wn->conf)
119 return -E_WRITE_COMMON_SYNTAX;
120 register_writer_node(wn, parent);
121 return 1;
122 }
123
124
125 /**
126 * Print the help text of all writers to stdout.
127 *
128 * \param detailed Whether to print the detailed help text.
129 */
130 void print_writer_helps(int detailed)
131 {
132 int i;
133
134 printf_or_die("\nAvailable writers: \n\t");
135 FOR_EACH_WRITER(i)
136 printf_or_die("%s%s", i? " " : "", writer_names[i]);
137 printf_or_die("\n\n");
138 FOR_EACH_WRITER(i) {
139 struct writer *w = writers + i;
140
141 if (!w->help.short_help)
142 continue;
143 printf_or_die("Options for %s:\n", writer_names[i]);
144 ggo_print_help(&w->help, detailed);
145 }
146 }
147
148 static int get_btr_value(struct btr_node *btrn, const char *key, int32_t *result)
149 {
150 char *buf = NULL;
151 int ret = btr_exec_up(btrn, key, &buf);
152
153 if (ret < 0)
154 return ret;
155 ret = para_atoi32(buf, result);
156 free(buf);
157 return ret;
158 }
159
160 /*
161 * Ask parent btr nodes for the samplerate of the current stream.
162 */
163 int get_btr_samplerate(struct btr_node *btrn, int32_t *result)
164 {
165 return get_btr_value(btrn, "samplerate", result);
166 }
167
168 /*
169 * Ask parent btr nodes for the channel count of the current stream.
170 */
171 int get_btr_channels(struct btr_node *btrn, int32_t *result)
172 {
173 return get_btr_value(btrn, "channels", result);
174 }