2d82a22c1c890865fa5d5c5c541b133872ed2471
2 * Copyright (C) 2005-2006 Andre Noll <maan@systemlinux.org>
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.
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.
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.
19 /** \file filter_chain.c common helper functions for filter input/output */
29 DEFINE_FILTER_ARRAY(filters
);
32 * call the init function of each supported filter
34 * \param all_filters the array of all supported filters
37 void filter_init(struct filter
*all_filters
)
41 for (f
= all_filters
; f
->name
; f
++)
46 * close and destroy a filter callback
48 * \param fcb the filter callback to close
50 * This removes \a fcb from the list of filter callbacks and calls
51 * the close callback associated with \a fcb.
53 static void close_filter_callback(struct filter_callback
*fcb
)
55 PARA_NOTICE_LOG("closing filter_callback %p, data: %p\n", fcb
, fcb
->data
);
61 * close all callbacks of a filter node
63 * \param fn the filter node which contains the filter callbacks to be closed
65 * Call close_filter_callback() for each entry in the filter callback list
68 static void close_callbacks(struct filter_node
*fn
)
70 struct filter_callback
*fcb
, *tmp
;
72 list_for_each_entry_safe(fcb
, tmp
, &fn
->callbacks
, node
) {
73 PARA_INFO_LOG("closing %s filter callback\n",
75 close_filter_callback(fcb
);
79 static void call_callbacks(struct filter_node
*fn
, char *inbuf
, size_t inlen
,
80 char *outbuf
, size_t outlen
)
82 struct filter_callback
*fcb
, *tmp
;
83 list_for_each_entry_safe(fcb
, tmp
, &fn
->callbacks
, node
) {
85 if (inlen
&& fcb
->input_cb
) {
86 ret
= fcb
->input_cb(inbuf
, inlen
, fcb
);
88 close_filter_callback(fcb
);
92 if (!outlen
|| !fcb
->output_cb
)
94 ret
= fcb
->output_cb(outbuf
, outlen
, fcb
);
96 close_filter_callback(fcb
);
101 * call the convert function of each filter
103 * This is the core function of the filter subsystem. It loops over the list of
104 * filter nodes determined by \a t and calls the filter's convert function if
105 * there is input available for the filter node in question. If the convert
106 * function consumed some or all of its input data, all registered input
107 * callbacks are called. Similarly, if a convert function produced output, all
108 * registerd output callbacks get called.
110 * \return The sum of output bytes produced by the convert functions on
111 * success, negative return value on errors (the return value is stored in
114 * \sa filter_node, filter#convert, filter_callback
116 void filter_pre_select(__a_unused
struct sched
*s
, struct task
*t
)
118 struct filter_chain
*fc
= t
->private_data
;
119 struct filter_node
*fn
;
122 int conv
, conv_total
= 0;
125 if (fc
->output_eof
&& *fc
->output_eof
)
127 if (fc
->input_eof
&& *fc
->input_eof
&& !*fc
->in_loaded
)
131 loaded
= fc
->in_loaded
;
133 list_for_each_entry(fn
, &fc
->filters
, node
) {
134 if (*loaded
&& fn
->loaded
< fn
->bufsize
) {
135 size_t old_fn_loaded
= fn
->loaded
;
136 PARA_DEBUG_LOG("fc %p loaded: %zd, calling %s convert\n",
137 fc
, *loaded
, fn
->filter
->name
);
138 t
->ret
= fn
->filter
->convert(ib
, *loaded
, fn
);
141 call_callbacks(fn
, ib
, t
->ret
, fn
->buf
+ old_fn_loaded
,
142 fn
->loaded
- old_fn_loaded
);
145 if (*loaded
&& t
->ret
) {
146 PARA_DEBUG_LOG("moving %zd bytes in input "
147 "buffer for %s filter\n",
148 *loaded
, fn
->filter
->name
);
149 memmove(ib
, ib
+ t
->ret
, *loaded
);
153 loaded
= &fn
->loaded
;
156 PARA_DEBUG_LOG("eof (in/out/fc): %d/%d/%d out_loaded: %d, "
157 "conv: %d, conv_total: %d\n", *fc
->input_eof
,
158 fc
->output_eof
? *fc
->output_eof
: -42,
159 fc
->eof
, *fc
->out_loaded
, conv
, conv_total
);
167 if (*fc
->in_loaded
&& conv_total
)
175 * close all filter nodes and its callbacks
177 * \param fc the filter chain to close
179 * For each filter node determined by \a fc, call the close function of each
180 * registered filter callback as well as the close function of the
181 * corresponding filter. Free all resources and destroy all callback lists and
182 * the filter node list.
184 * \sa filter::close, filter_callback::close
186 void close_filters(struct filter_chain
*fc
)
188 struct filter_node
*fn
, *tmp
;
192 PARA_NOTICE_LOG("closing filter chain %p\n", fc
);
193 list_for_each_entry_safe(fn
, tmp
, &fc
->filters
, node
) {
195 PARA_INFO_LOG("closing %s filter\n", fn
->filter
->name
);
196 fn
->filter
->close(fn
);
203 * If the filter has a command line parser and options is not NULL, run it.
204 * Returns filter_num on success, negative on errors
206 static int parse_filter_args(int filter_num
, char *options
, void **conf
)
208 struct filter
*f
= &filters
[filter_num
];
212 // PARA_DEBUG_LOG("%s, options: %s, parser: %p\n", f->name,
213 // options? options : "(none)", f->parse_config);
214 if (!f
->parse_config
)
215 return strlen(options
)? -E_BAD_FILTER_OPTIONS
: filter_num
;
216 // PARA_DEBUG_LOG("options: %s\n", options);
217 argc
= split_args(options
, &argv
, " \t");
218 // PARA_DEBUG_LOG("argc = %d, argv[0]: %s\n", argc, argv[0]);
219 for (i
= argc
- 1; i
>= 0; i
--)
220 argv
[i
+ 1] = argv
[i
];
221 argv
[0] = para_strdup(f
->name
);
223 *conf
= f
->parse_config(argc
, argv
);
224 return *conf
? filter_num
: -E_BAD_FILTER_OPTIONS
;
228 * check the filter command line options
230 * \param fa the command line options
231 * \param conf points to the filter configuration upon successful return
233 * Check if \a fa starts with a the name of a supported filter, followed by
234 * a colon. If yes, call the command line parser of that filter.
236 * \return On success, the number of the filter is returned and \a conf
237 * is initialized to point to the filter configuration determined by \a fa.
238 * On errors, a negative value is returned.
240 * Note: If \a fa specifies a filter that has no command line parser success is
241 * returned, and \a conf is initialized to \p NULL.
243 * \sa filter::parse_config
245 int check_filter_arg(char *fa
, void **conf
)
250 // PARA_DEBUG_LOG("arg: %s\n", fa);
251 for (j
= 0; filters
[j
].name
; j
++) {
252 const char *name
= filters
[j
].name
;
253 size_t len
= strlen(name
);
255 if (strlen(fa
) < len
)
257 if (strncmp(name
, fa
, len
))
262 if (c
&& !filters
[j
].parse_config
)
263 return -E_BAD_FILTER_OPTIONS
;
264 return parse_filter_args(j
, c
? fa
+ len
+ 1 :
265 fa
+ strlen(fa
), conf
);
267 return -E_UNSUPPORTED_FILTER
;