convert para_audiod to the new scheduler.
[paraslash.git] / filter_chain.c
1 /*
2 * Copyright (C) 2005-2006 Andre Noll <maan@systemlinux.org>
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA.
17 */
18
19 /** \file filter_chain.c common helper functions for filter input/output */
20
21 #include "para.h"
22 #include "list.h"
23 #include "sched.h"
24 #include "fd.h"
25 #include "filter.h"
26 #include "error.h"
27 #include "string.h"
28
29 DEFINE_FILTER_ARRAY(filters);
30
31 /**
32 * call the init function of each supported filter
33 *
34 * \param all_filters the array of all supported filters
35 * \sa filter::init
36 */
37 void filter_init(struct filter *all_filters)
38 {
39 struct filter *f;
40
41 for (f = all_filters; f->name; f++)
42 f->init(f);
43 }
44
45 /**
46 * close and destroy a filter callback
47 *
48 * \param fcb the filter callback to close
49 *
50 * This removes \a fcb from the list of filter callbacks and calls
51 * the close callback associated with \a fcb.
52 */
53 static void close_filter_callback(struct filter_callback *fcb)
54 {
55 PARA_NOTICE_LOG("closing filter_callback %p, data: %p\n", fcb, fcb->data);
56 list_del(&fcb->node);
57 fcb->close(fcb);
58 }
59
60 /**
61 * close all callbacks of a filter node
62 *
63 * \param fn the filter node which contains the filter callbacks to be closed
64 *
65 * Call close_filter_callback() for each entry in the filter callback list
66 * of \a fn.
67 */
68 static void close_callbacks(struct filter_node *fn)
69 {
70 struct filter_callback *fcb, *tmp;
71
72 list_for_each_entry_safe(fcb, tmp, &fn->callbacks, node)
73 close_filter_callback(fcb);
74 }
75
76 static void call_callbacks(struct filter_node *fn, char *inbuf, size_t inlen,
77 char *outbuf, size_t outlen)
78 {
79 struct filter_callback *fcb, *tmp;
80 list_for_each_entry_safe(fcb, tmp, &fn->callbacks, node) {
81 int ret;
82 if (inlen && fcb->input_cb) {
83 ret = fcb->input_cb(inbuf, inlen, fcb);
84 if (ret < 0) {
85 close_filter_callback(fcb);
86 continue;
87 }
88 }
89 if (!outlen || !fcb->output_cb)
90 continue;
91 ret = fcb->output_cb(outbuf, outlen, fcb);
92 if (ret < 0)
93 close_filter_callback(fcb);
94 }
95 }
96
97 /**
98 * call the convert function of each filter
99 *
100 * This is the core function of the filter subsystem. It loops over the list of
101 * filter nodes determined by \a t and calls the filter's convert function if
102 * there is input available for the filter node in question. If the convert
103 * function consumed some or all of its input data, all registered input
104 * callbacks are called. Similarly, if a convert function produced output, all
105 * registerd output callbacks get called.
106 *
107 * \return The sum of output bytes produced by the convert functions on
108 * success, negative return value on errors (the return value is stored in
109 * t->ret).
110 *
111 * \sa filter_node, filter#convert, filter_callback
112 */
113 void filter_pre_select(__a_unused struct sched *s, struct task *t)
114 {
115 struct filter_chain *fc = t->private_data;
116 struct filter_node *fn;
117 char *ib;
118 size_t *loaded;
119 int conv, conv_total = 0;
120
121 t->ret = -E_FC_EOF;
122 if (*fc->output_eof)
123 goto err_out;
124 again:
125 ib = fc->inbuf;
126 loaded = fc->in_loaded;
127 conv = 0;
128 list_for_each_entry(fn, &fc->filters, node) {
129 if (*loaded && fn->loaded < fn->bufsize) {
130 size_t old_fn_loaded = fn->loaded;
131 PARA_DEBUG_LOG("fc %p loaded: %zd, calling %s convert\n",
132 fc, *loaded, fn->filter->name);
133 t->ret = fn->filter->convert(ib, *loaded, fn);
134 if (t->ret < 0)
135 goto err_out;
136 call_callbacks(fn, ib, t->ret, fn->buf + old_fn_loaded,
137 fn->loaded - old_fn_loaded);
138 *loaded -= t->ret;
139 conv += t->ret;
140 if (*loaded && t->ret) {
141 PARA_DEBUG_LOG("moving %zd bytes in input buffer for %s filter\n",
142 *loaded, fn->filter->name);
143 memmove(ib, ib + t->ret, *loaded);
144 }
145 }
146 ib = fn->buf;
147 loaded = &fn->loaded;
148 }
149 conv_total += conv;
150 PARA_DEBUG_LOG("eof (in/out/fc): %d/%d/%d out_loaded: %d, conv: %d, conv_total: %d\n", *fc->input_eof,
151 *fc->output_eof, fc->eof, *fc->out_loaded, conv, conv_total);
152 if (conv)
153 goto again;
154 t->ret = 1;
155 if (!*fc->input_eof)
156 return;
157 if (*fc->out_loaded)
158 return;
159 if (*fc->in_loaded && conv_total)
160 return;
161 t->ret = -E_FC_EOF;
162 err_out:
163 fc->eof = 1;
164 }
165
166 /**
167 * close all filter nodes and its callbacks
168 *
169 * \param fc the filter chain to close
170 *
171 * For each filter node determined by \a fc, call the close function of each
172 * registered filter callback as well as the close function of the
173 * corresponding filter. Free all resources and destroy all callback lists and
174 * the filter node list.
175 *
176 * \sa filter::close, filter_callback::close
177 */
178 void close_filters(struct filter_chain *fc)
179 {
180 struct filter_node *fn, *tmp;
181
182 if (!fc)
183 return;
184 PARA_DEBUG_LOG("closing filter chain %p\n", fc);
185 list_for_each_entry_safe(fn, tmp, &fc->filters, node) {
186 PARA_NOTICE_LOG("closing %s filter callbacks (fc %p, fn %p)\n", fn->filter->name, fc, fn);
187 close_callbacks(fn);
188 PARA_NOTICE_LOG("closing %s filter (fc %p, fn %p)\n", fn->filter->name, fc, fn);
189 fn->filter->close(fn);
190 list_del(&fn->node);
191 free(fn);
192 }
193 }
194
195 /*
196 * If the filter has a command line parser and options is not NULL, run it.
197 * Returns filter_num on success, negative on errors
198 */
199 static int parse_filter_args(int filter_num, char *options, void **conf)
200 {
201 struct filter *f = &filters[filter_num];
202 int i, argc = 2;
203 char **argv;
204
205 // PARA_DEBUG_LOG("%s, options: %s, parser: %p\n", f->name,
206 // options? options : "(none)", f->parse_config);
207 if (!f->parse_config)
208 return strlen(options)? -E_BAD_FILTER_OPTIONS : filter_num;
209 // PARA_DEBUG_LOG("options: %s\n", options);
210 argc = split_args(options, &argv, " \t");
211 // PARA_DEBUG_LOG("argc = %d, argv[0]: %s\n", argc, argv[0]);
212 for (i = argc - 1; i >= 0; i--)
213 argv[i + 1] = argv[i];
214 argv[0] = para_strdup(f->name);
215 argc += 1;
216 *conf = f->parse_config(argc, argv);
217 return *conf? filter_num : -E_BAD_FILTER_OPTIONS;
218 }
219
220 /**
221 * check the filter command line options
222 *
223 * \param fa the command line options
224 * \param conf points to the filter configuration upon successful return
225 *
226 * Check if \a fa starts with a the name of a supported filter, followed by
227 * a colon. If yes, call the command line parser of that filter.
228 *
229 * \return On success, the number of the filter is returned and \a conf
230 * is initialized to point to the filter configuration determined by \a fa.
231 * On errors, a negative value is returned.
232 *
233 * Note: If \a fa specifies a filter that has no command line parser success is
234 * returned, and \a conf is initialized to \p NULL.
235 *
236 * \sa filter::parse_config
237 */
238 int check_filter_arg(char *fa, void **conf)
239 {
240 int j;
241
242 *conf = NULL;
243 // PARA_DEBUG_LOG("arg: %s\n", fa);
244 for (j = 0; filters[j].name; j++) {
245 const char *name = filters[j].name;
246 size_t len = strlen(name);
247 char c;
248 if (strlen(fa) < len)
249 continue;
250 if (strncmp(name, fa, len))
251 continue;
252 c = fa[len];
253 if (c && c != ' ')
254 continue;
255 if (c && !filters[j].parse_config)
256 return -E_BAD_FILTER_OPTIONS;
257 return parse_filter_args(j, c? fa + len + 1 :
258 fa + strlen(fa), conf);
259 }
260 return -E_UNSUPPORTED_FILTER;
261 }
262