b92c5f1ca64f04328a482f9105d9280968e7877a
[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(&(struct btr_node_description)
85 EMBRACE(.name = name, .parent = parent,
86 .handler = w->execute, .context = wn));
87 strcpy(wn->task.status, name);
88 free(name);
89 ret = w->open(wn);
90 wn->task.post_select = w->post_select;
91 wn->task.pre_select = w->pre_select;
92 register_task(&wn->task);
93 }
94
95 /**
96 * Setup a writer node with the default writer.
97 *
98 * If arg is \p NULL, the OS-dependent default writer is used with an empty
99 * configuration string. It defaults to alsa for Linux, osx for OS X, oss for
100 * *BSD and the file writer if neither of these is supported.
101 *
102 * Once the writer configuration has been retrieved, a writer node is created,
103 * its buffer tree node is added to the buffer tree as a child of the given
104 * parent.
105 *
106 * Finally, the new writer node's taks structure is initialized and registered
107 * to the paraslash scheduler.
108 *
109 * \return A pointer to the allocated writer node group.
110 */
111 int setup_writer_node(const char *arg, struct btr_node *parent,
112 struct writer_node *wn)
113 {
114 if (arg)
115 wn->conf = check_writer_arg(arg, &wn->writer_num);
116 else {
117 wn->writer_num = DEFAULT_WRITER;
118 wn->conf = writers[DEFAULT_WRITER].parse_config("");
119 }
120 if (!wn->conf)
121 return -E_WRITE_COMMON_SYNTAX;
122 register_writer_node(wn, parent);
123 return 1;
124 }
125
126
127 /**
128 * Print the help text of all writers to stdout.
129 *
130 * \param detailed Whether to print the detailed help text.
131 */
132 void print_writer_helps(int detailed)
133 {
134 int i;
135
136 printf_or_die("\nAvailable writers: \n\t");
137 FOR_EACH_WRITER(i)
138 printf_or_die("%s%s", i? " " : "", writer_names[i]);
139 printf_or_die("\n\n");
140 FOR_EACH_WRITER(i) {
141 struct writer *w = writers + i;
142
143 if (!w->help.short_help)
144 continue;
145 printf_or_die("Options for %s:\n", writer_names[i]);
146 ggo_print_help(&w->help, detailed);
147 }
148 }
149
150 static int get_btr_value(struct btr_node *btrn, const char *key, int32_t *result)
151 {
152 char *buf = NULL;
153 int ret = btr_exec_up(btrn, key, &buf);
154
155 if (ret < 0)
156 return ret;
157 ret = para_atoi32(buf, result);
158 free(buf);
159 return ret;
160 }
161
162 /*
163 * Ask parent btr nodes for the samplerate of the current stream.
164 */
165 int get_btr_samplerate(struct btr_node *btrn, int32_t *result)
166 {
167 return get_btr_value(btrn, "samplerate", result);
168 }
169
170 /*
171 * Ask parent btr nodes for the channel count of the current stream.
172 */
173 int get_btr_channels(struct btr_node *btrn, int32_t *result)
174 {
175 return get_btr_value(btrn, "channels", result);
176 }