Rename struct rc4_context and stream cipher send/receive functions.
[paraslash.git] / filter_common.c
1 /*
2 * Copyright (C) 2005-2011 Andre Noll <maan@systemlinux.org>
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 #include <dirent.h>
12 #include <stdbool.h>
13
14 #include "para.h"
15 #include "list.h"
16 #include "sched.h"
17 #include "fd.h"
18 #include "ggo.h"
19 #include "buffer_tree.h"
20 #include "filter.h"
21 #include "error.h"
22 #include "string.h"
23
24 /** The array of supported filters. */
25 struct filter filters[NUM_SUPPORTED_FILTERS] = {FILTER_ARRAY};
26
27 /**
28 * Call the init function of each supported filter.
29 * \sa filter::init
30 */
31 void filter_init(void)
32 {
33 int i;
34
35 FOR_EACH_SUPPORTED_FILTER(i)
36 filters[i].init(filters + i);
37 }
38
39 /*
40 * If the filter has a command line parser and options is not NULL, run it.
41 * Returns filter_num on success, negative on errors
42 */
43 static int parse_filter_args(int filter_num, char *options, void **conf)
44 {
45 struct filter *f = &filters[filter_num];
46 int ret, i, argc = 2;
47 char **argv;
48
49 // PARA_DEBUG_LOG("%s, options: %s, parser: %p\n", f->name,
50 // options? options : "(none)", f->parse_config);
51 if (!f->parse_config)
52 return strlen(options)? -E_BAD_FILTER_OPTIONS : filter_num;
53 // PARA_DEBUG_LOG("options: %s\n", options);
54 argc = create_argv(options, " \t", &argv);
55 if (argc < 0)
56 return -E_BAD_FILTER_OPTIONS;
57 PARA_DEBUG_LOG("argc = %d, argv[0]: %s\n", argc, argv[0]);
58 for (i = argc - 1; i >= 0; i--)
59 argv[i + 1] = argv[i];
60 argv[0] = para_strdup(f->name);
61 argc++;
62 ret = f->parse_config(argc, argv, conf);
63 free(argv[argc - 1]);
64 argv[argc - 1] = NULL;
65 free_argv(argv);
66 return ret < 0? ret : filter_num;
67 }
68
69 /**
70 * Check the filter command line options.
71 *
72 * \param fa The command line options.
73 * \param conf Points to the filter configuration upon successful return.
74 *
75 * Check if \a fa starts with a the name of a supported filter, followed by
76 * a colon. If yes, call the command line parser of that filter.
77 *
78 * \return On success, the number of the filter is returned and \a conf
79 * is initialized to point to the filter configuration determined by \a fa.
80 * On errors, a negative value is returned.
81 *
82 * Note: If \a fa specifies a filter that has no command line parser success is
83 * returned, and \a conf is initialized to \p NULL.
84 *
85 * \sa filter::parse_config
86 */
87 int check_filter_arg(char *fa, void **conf)
88 {
89 int j;
90
91 *conf = NULL;
92 // PARA_DEBUG_LOG("arg: %s\n", fa);
93 FOR_EACH_SUPPORTED_FILTER(j) {
94 const char *name = filters[j].name;
95 size_t len = strlen(name);
96 char c;
97 if (strlen(fa) < len)
98 continue;
99 if (strncmp(name, fa, len))
100 continue;
101 c = fa[len];
102 if (c && c != ' ')
103 continue;
104 if (c && !filters[j].parse_config)
105 return -E_BAD_FILTER_OPTIONS;
106 return parse_filter_args(j, c? fa + len + 1 :
107 fa + strlen(fa), conf);
108 }
109 return -E_UNSUPPORTED_FILTER;
110 }
111
112 void print_filter_helps(int detailed)
113 {
114 int i;
115
116 printf_or_die("\nAvailable filters: \n\t");
117 FOR_EACH_SUPPORTED_FILTER(i)
118 printf_or_die("%s%s", i? " " : "", filters[i].name);
119 printf_or_die("\n\n");
120
121 FOR_EACH_SUPPORTED_FILTER(i) {
122 struct filter *f = filters + i;
123
124 if (!f->help.short_help)
125 continue;
126 printf_or_die("Options for %s:\n", f->name);
127 ggo_print_help(&f->help, detailed);
128 }
129 }
130
131 void generic_filter_pre_select(struct sched *s, struct task *t)
132 {
133 struct filter_node *fn = container_of(t, struct filter_node, task);
134
135 t->error = 0;
136 if (btr_node_status(fn->btrn, fn->min_iqs, BTR_NT_INTERNAL) != 0)
137 sched_min_delay(s);
138 }
139
140 #ifdef WORDS_BIGENDIAN
141 #define DECODER_SAMPLE_FORMAT SF_S16_BE
142 #else
143 #define DECODER_SAMPLE_FORMAT SF_S16_LE
144 #endif
145
146 /**
147 * Execute a btr command for a decoder.
148 *
149 * The buffer tree nodes of the writers ask the parent nodes about sample_rate,
150 * channels count and sample format. This function is called by all decoders to
151 * answer these queries.
152 *
153 * \param cmd The command to be executed by the child node.
154 * \param sample_rate Known to the decoder.
155 * \param channels Known to the decoder.
156 * \param result Ascii representation on the answer is stored here.
157 */
158 int decoder_execute(const char *cmd, unsigned sample_rate, unsigned channels,
159 char **result)
160 {
161 if (!strcmp(cmd, "sample_rate")) {
162 if (sample_rate == 0)
163 return -E_BTR_NAVAIL;
164 *result = make_message("%u", sample_rate);
165 return 1;
166 }
167 if (!strcmp(cmd, "channels")) {
168 if (channels == 0)
169 return -E_BTR_NAVAIL;
170 *result = make_message("%u", channels);
171 return 1;
172 }
173 if (!strcmp(cmd, "sample_format")) {
174 *result = make_message("%u", DECODER_SAMPLE_FORMAT);
175 return 1;
176 }
177 return -ERRNO_TO_PARA_ERROR(ENOTSUP);
178 }