Merge branch 't/remove_sb_compat'
[paraslash.git] / write_common.c
1 /*
2 * Copyright (C) 2006-2013 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
11 #include "para.h"
12 #include "string.h"
13 #include "list.h"
14 #include "sched.h"
15 #include "ggo.h"
16 #include "buffer_tree.h"
17 #include "write.h"
18 #include "error.h"
19
20 /** the array containing the names of all supported writers */
21 const char *writer_names[] ={WRITER_NAMES};
22
23 /** the array of supported writers */
24 struct writer writers[NUM_SUPPORTED_WRITERS] = {WRITER_ARRAY};
25
26 /**
27 * Call the init function of each supported paraslash writer.
28 */
29 void writer_init(void)
30 {
31 int i;
32
33 FOR_EACH_WRITER(i)
34 writers[i].init(&writers[i]);
35 }
36 /**
37 * Check if given string is a valid command line for any writer.
38 *
39 * \param \wa String of the form writer_name:options.
40 * \param writer_num Contains the number of the writer upon success.
41 *
42 * This function checks whether \a wa starts with the name of a supported
43 * paraslash writer, optionally followed by a colon and any options for that
44 * writer. If a valid writer name was found and further are present, the
45 * remaining part of \a wa is passed to that writer's config parser.
46 *
47 * \return On success, a pointer to the gengetopt args info struct is returned
48 * and \a writer_num contains the number of the writer. Otherwise this function
49 * prints an error message and calls exit().
50 */
51 void *check_writer_arg_or_die(const char *wa, int *writer_num)
52 {
53 int i, ret, argc;
54 const char *cmdline;
55 char **argv;
56 void *conf;
57
58 if (!wa || !*wa) {
59 i = DEFAULT_WRITER;
60 cmdline = NULL;
61 goto check;
62 }
63 PARA_INFO_LOG("checking %s\n", wa);
64 FOR_EACH_WRITER(i) {
65 const char *name = writer_names[i];
66 size_t len = strlen(name);
67 char c;
68
69 if (strlen(wa) < len)
70 continue;
71 if (strncmp(name, wa, len))
72 continue;
73 c = wa[len];
74 if (!c || c == ' ') {
75 cmdline = c? wa + len + 1 : NULL;
76 goto check;
77 }
78 }
79 PARA_EMERG_LOG("invalid writer %s\n", wa);
80 exit(EXIT_FAILURE);
81 check:
82 ret = create_shifted_argv(cmdline, " \t", &argv);
83 if (ret < 0) {
84 PARA_EMERG_LOG("%s: %s\n", wa, para_strerror(-ret));
85 exit(EXIT_FAILURE);
86 }
87 argc = ret;
88 argv[0] = make_message("%s_write", writer_names[i]);
89 *writer_num = i;
90 conf = writers[i].parse_config_or_die(argc, argv);
91 free_argv(argv);
92 return conf;
93 }
94
95 /**
96 * Open a writer node and register the corresponding task.
97 *
98 * \param wn The writer node to open.
99 * \param parent The parent btr node (the source for the writer node).
100 * \param s The scheduler instance to register the task to.
101 *
102 * The configuration of the writer node stored in \p wn->conf must be
103 * initialized before this function may be called.
104 */
105 void register_writer_node(struct writer_node *wn, struct btr_node *parent,
106 struct sched *s)
107 {
108 struct writer *w = writers + wn->writer_num;
109 char *name = make_message("%s writer", writer_names[wn->writer_num]);
110
111 wn->btrn = btr_new_node(&(struct btr_node_description)
112 EMBRACE(.name = name, .parent = parent,
113 .handler = w->execute, .context = wn));
114 strcpy(wn->task.status, name);
115 free(name);
116 wn->task.pre_select = w->pre_select;
117 wn->task.post_select = w->post_select;
118 register_task(s, &wn->task);
119 }
120
121 /**
122 * Print the help text of all writers to stdout.
123 *
124 * \param flags Passed to \ref ggo_print_help().
125 */
126 void print_writer_helps(unsigned flags)
127 {
128 int i;
129
130 printf_or_die("\nAvailable writers: ");
131 FOR_EACH_WRITER(i)
132 printf_or_die("%s%s", i? " " : "", writer_names[i]);
133 printf_or_die("\n");
134 FOR_EACH_WRITER(i) {
135 struct writer *w = writers + i;
136
137 if (!w->help.short_help)
138 continue;
139 printf_or_die("\n%s: %s", writer_names[i],
140 w->help.purpose);
141 ggo_print_help(&w->help, flags);
142 }
143 }
144
145 static void get_btr_value(struct btr_node *btrn, const char *cmd,
146 int32_t *result)
147 {
148 char *buf = NULL;
149 int ret = btr_exec_up(btrn, cmd, &buf);
150
151 if (ret < 0) {
152 /*
153 * This really should not happen. It means one of our parent
154 * nodes died unexpectedly. Proceed with fingers crossed.
155 */
156 PARA_CRIT_LOG("cmd %s: %s\n", cmd, para_strerror(-ret));
157 *result = 0;
158 return;
159 }
160 ret = para_atoi32(buf, result);
161 assert(ret >= 0);
162 free(buf);
163 }
164
165 /**
166 * Ask parent btr nodes for the sample rate of the current stream.
167 *
168 * \param btrn Where to start the search.
169 * \param result Filled in by this function.
170 *
171 * This function is assumed to succeed and terminates on errors.
172 */
173 void get_btr_sample_rate(struct btr_node *btrn, int32_t *result)
174 {
175 get_btr_value(btrn, "sample_rate", result);
176 }
177
178 /**
179 * Ask parent btr nodes for the channel count of the current stream.
180 *
181 * \param btrn See \ref get_btr_sample_rate.
182 * \param result See \ref get_btr_sample_rate.
183 */
184 void get_btr_channels(struct btr_node *btrn, int32_t *result)
185 {
186 get_btr_value(btrn, "channels", result);
187 }
188
189 /**
190 * Ask parent btr nodes for the number of bits per sample and the byte sex.
191 *
192 * \param btrn See \ref get_btr_sample_rate.
193 * \param result Contains the sample format as an enum sample_format type.
194 */
195 void get_btr_sample_format(struct btr_node *btrn, int32_t *result)
196 {
197 get_btr_value(btrn, "sample_format", result);
198 }