Merge branch 't/interactive'
[paraslash.git] / write_common.c
1 /*
2 * Copyright (C) 2006-2011 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 * prints an error message and calls exit().
51 */
52 void *check_writer_arg_or_die(const char *wa, int *writer_num)
53 {
54 int i;
55
56 PARA_INFO_LOG("checking %s\n", wa);
57 FOR_EACH_WRITER(i) {
58 const char *name = writer_names[i];
59 size_t len = strlen(name);
60 char c;
61 if (strlen(wa) < len)
62 continue;
63 if (strncmp(name, wa, len))
64 continue;
65 c = wa[len];
66 if (c && c != ' ')
67 continue;
68 *writer_num = i;
69 return writers[i].parse_config_or_die(c? wa + len + 1 : "");
70 }
71 PARA_EMERG_LOG("invalid writer %s\n", wa);
72 exit(EXIT_FAILURE);
73 }
74
75 /**
76 * Open a writer node and register the corresponding task.
77 *
78 * \param wn The writer node to open.
79 * \param parent The parent btr node (the source for the writer node).
80 * \param s The scheduler instance to register the task to.
81 *
82 * The configuration of the writer node stored in \p wn->conf must be
83 * initialized before this function may be called.
84 */
85 void register_writer_node(struct writer_node *wn, struct btr_node *parent,
86 struct sched *s)
87 {
88 struct writer *w = writers + wn->writer_num;
89 char *name = make_message("%s writer", writer_names[wn->writer_num]);
90
91 wn->btrn = btr_new_node(&(struct btr_node_description)
92 EMBRACE(.name = name, .parent = parent,
93 .handler = w->execute, .context = wn));
94 strcpy(wn->task.status, name);
95 free(name);
96 wn->task.post_select = w->post_select;
97 wn->task.pre_select = w->pre_select;
98 register_task(s, &wn->task);
99 }
100
101 /**
102 * Print the help text of all writers to stdout.
103 *
104 * \param detailed Whether to print the detailed help text.
105 */
106 void print_writer_helps(int detailed)
107 {
108 int i;
109
110 printf_or_die("\nAvailable writers: \n\t");
111 FOR_EACH_WRITER(i)
112 printf_or_die("%s%s", i? " " : "", writer_names[i]);
113 printf_or_die("\n\n");
114 FOR_EACH_WRITER(i) {
115 struct writer *w = writers + i;
116
117 if (!w->help.short_help)
118 continue;
119 printf_or_die("Options for %s:\n", writer_names[i]);
120 ggo_print_help(&w->help, detailed);
121 }
122 }
123
124 static void get_btr_value(struct btr_node *btrn, const char *cmd,
125 int32_t *result)
126 {
127 char *buf = NULL;
128 int ret = btr_exec_up(btrn, cmd, &buf);
129
130 if (ret < 0) {
131 /*
132 * This really should not happen. It means one of our parent
133 * nodes died unexpectedly. Proceed with fingers crossed.
134 */
135 PARA_CRIT_LOG("cmd %s: %s\n", cmd, para_strerror(-ret));
136 *result = 0;
137 return;
138 }
139 ret = para_atoi32(buf, result);
140 assert(ret >= 0);
141 free(buf);
142 }
143
144 /**
145 * Ask parent btr nodes for the sample rate of the current stream.
146 *
147 * \param btrn Where to start the search.
148 * \param result Filled in by this function.
149 *
150 * This function is assumed to succeed and terminates on errors.
151 */
152 void get_btr_sample_rate(struct btr_node *btrn, int32_t *result)
153 {
154 get_btr_value(btrn, "sample_rate", result);
155 }
156
157 /**
158 * Ask parent btr nodes for the channel count of the current stream.
159 *
160 * \param btrn See \ref get_btr_sample_rate.
161 * \param result See \ref get_btr_sample_rate.
162 */
163 void get_btr_channels(struct btr_node *btrn, int32_t *result)
164 {
165 get_btr_value(btrn, "channels", result);
166 }
167
168 /**
169 * Ask parent btr nodes for the number of bits per sample and the byte sex.
170 *
171 * \param btrn See \ref get_btr_sample_rate.
172 * \param result Contains the sample format as an enum sample_format type.
173 */
174 void get_btr_sample_format(struct btr_node *btrn, int32_t *result)
175 {
176 get_btr_value(btrn, "sample_format", result);
177 }