test suite: Fail test if para_server could not be started.
[paraslash.git] / filter_common.c
1 /*
2 * Copyright (C) 2005 Andre Noll <maan@tuebingen.mpg.de>
3 *
4 * Licensed under the GPL v2. For licencing details see COPYING.
5 */
6
7 /** \file filter_common.c Common helper functions for filter input/output. */
8
9 #include <regex.h>
10 #include <sys/types.h>
11
12 #include "para.h"
13 #include "list.h"
14 #include "sched.h"
15 #include "fd.h"
16 #include "ggo.h"
17 #include "buffer_tree.h"
18 #include "filter.h"
19 #include "error.h"
20 #include "string.h"
21
22 /** Iterate over the array of supported filters. */
23 #define FOR_EACH_SUPPORTED_FILTER(j) for (j = 0; j < NUM_SUPPORTED_FILTERS; j++)
24
25 /** The array of supported filters. */
26 static struct filter filters[NUM_SUPPORTED_FILTERS] = {FILTER_ARRAY};
27
28 /**
29 * Obtain a reference to a filter structure.
30 *
31 * \param filter_num Between zero and NUM_SUPPORTED_FILTERS, inclusively.
32 *
33 * \return Pointer to the filter identified by the given filter number.
34 *
35 * It is a fatal error if the given number is out of range. In this case
36 * the function aborts.
37 */
38 const struct filter *filter_get(int filter_num)
39 {
40 assert(filter_num >= 0);
41 assert(filter_num < NUM_SUPPORTED_FILTERS);
42 return filters + filter_num;
43 }
44
45 /**
46 * Call the init function of each supported filter.
47 * \sa filter::init
48 */
49 void filter_init(void)
50 {
51 int i;
52
53 FOR_EACH_SUPPORTED_FILTER(i)
54 filter_get(i)->init((struct filter *)filter_get(i));
55 }
56
57 /*
58 * If the filter has a command line parser and options is not NULL, run it.
59 * Returns filter_num on success, negative on errors
60 */
61 static int parse_filter_args(int filter_num, char *options, void **conf)
62 {
63 const struct filter *f = filter_get(filter_num);
64 int ret, argc;
65 char **argv;
66
67 if (!f->parse_config)
68 return strlen(options)? -E_BAD_FILTER_OPTIONS : filter_num;
69 argc = create_shifted_argv(options, " \t", &argv);
70 if (argc < 0)
71 return -E_BAD_FILTER_OPTIONS;
72 argv[0] = para_strdup(f->name);
73 ret = f->parse_config(argc, argv, conf);
74 free_argv(argv);
75 return ret < 0? ret : filter_num;
76 }
77
78 /**
79 * Check the filter command line options.
80 *
81 * \param fa The command line options.
82 * \param conf Points to the filter configuration upon successful return.
83 *
84 * Check if \a fa starts with a the name of a supported filter, followed by
85 * a colon. If yes, call the command line parser of that filter.
86 *
87 * \return On success, the number of the filter is returned and \a conf
88 * is initialized to point to the filter configuration determined by \a fa.
89 * On errors, a negative value is returned.
90 *
91 * Note: If \a fa specifies a filter that has no command line parser success is
92 * returned, and \a conf is initialized to \p NULL.
93 *
94 * \sa filter::parse_config
95 */
96 int check_filter_arg(char *fa, void **conf)
97 {
98 int j;
99
100 *conf = NULL;
101 // PARA_DEBUG_LOG("arg: %s\n", fa);
102 FOR_EACH_SUPPORTED_FILTER(j) {
103 const char *name = filter_get(j)->name;
104 size_t len = strlen(name);
105 char c;
106 if (strlen(fa) < len)
107 continue;
108 if (strncmp(name, fa, len))
109 continue;
110 c = fa[len];
111 if (c && c != ' ')
112 continue;
113 if (c && !filter_get(j)->parse_config)
114 return -E_BAD_FILTER_OPTIONS;
115 return parse_filter_args(j, c? fa + len + 1 :
116 fa + strlen(fa), conf);
117 }
118 return -E_UNSUPPORTED_FILTER;
119 }
120
121 /**
122 * Print help text of each filter to stdout.
123 *
124 * \param flags Passed to \ref ggo_print_help().
125 */
126 void print_filter_helps(unsigned flags)
127 {
128 int i, num = 0;
129
130 printf_or_die("\nAvailable filters: ");
131 FOR_EACH_SUPPORTED_FILTER(i) {
132 if (num > 50) {
133 printf_or_die("\n ");
134 num = 0;
135 }
136 num += printf_or_die("%s%s", i? " " : "", filter_get(i)->name);
137 }
138 printf_or_die("\n");
139
140 FOR_EACH_SUPPORTED_FILTER(i) {
141 struct filter *f = (struct filter *)filter_get(i);
142
143 if (!f->help.short_help)
144 continue;
145 printf_or_die("\nOptions for %s (%s):", f->name,
146 f->help.purpose);
147 ggo_print_help(&f->help, flags);
148 }
149 }
150
151 /**
152 * Set select timeout of the scheduler.
153 *
154 * \param s The scheduler.
155 * \param context Pointer to the filter node (task context).
156 *
157 * This looks at the status of the btr node of the filter. If data is available
158 * in the input queue of the filter, or if an error occurred, a minimal timeout
159 * for the next select call is requested from the scheduler. Otherwise the
160 * scheduler timeout is left unchanged.
161 */
162 void generic_filter_pre_select(struct sched *s, void *context)
163 {
164 struct filter_node *fn = context;
165
166 if (btr_node_status(fn->btrn, fn->min_iqs, BTR_NT_INTERNAL) != 0)
167 sched_min_delay(s);
168 }
169
170 #ifdef WORDS_BIGENDIAN
171 #define DECODER_SAMPLE_FORMAT SF_S16_BE
172 #else
173 #define DECODER_SAMPLE_FORMAT SF_S16_LE
174 #endif
175
176 /**
177 * Execute a btr command for a decoder.
178 *
179 * The buffer tree nodes of the writers ask the parent nodes about sample_rate,
180 * channels count and sample format. This function is called by all decoders to
181 * answer these queries.
182 *
183 * \param cmd The command to be executed by the child node.
184 * \param sample_rate Known to the decoder.
185 * \param channels Known to the decoder.
186 * \param result Ascii representation on the answer is stored here.
187 *
188 * \return Standard.
189 */
190 int decoder_execute(const char *cmd, unsigned sample_rate, unsigned channels,
191 char **result)
192 {
193 if (!strcmp(cmd, "sample_rate")) {
194 if (sample_rate == 0)
195 return -E_BTR_NAVAIL;
196 *result = make_message("%u", sample_rate);
197 return 1;
198 }
199 if (!strcmp(cmd, "channels")) {
200 if (channels == 0)
201 return -E_BTR_NAVAIL;
202 *result = make_message("%u", channels);
203 return 1;
204 }
205 if (!strcmp(cmd, "sample_format")) {
206 *result = make_message("%u", DECODER_SAMPLE_FORMAT);
207 return 1;
208 }
209 return -ERRNO_TO_PARA_ERROR(ENOTSUP);
210 }