grab_client.c

   1 /*
   2  * Copyright (C) 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 /**
  20  * \file grab_client.c functions for grabbing the stream at any position
  21  * in a filter chain
  22  *
  23  * \sa filter_chain filter_chain_info filter
  24  */
  25
  26 #include "para.h"
  27 #include "close_on_fork.h"
  28 #include "grab_client.cmdline.h"
  29 #include "list.h"
  30 #include "filter.h"
  31 #include "grab_client.h"
  32 #include "audiod.h"
  33 #include "error.h"
  34 #include "string.h"
  35
  36
  37 /** this maps the enum to the text used at the command line */
  38 static const char *gc_modes[] = {
  39         [GRAB_PEDANTIC] = "pedantic",
  40         [GRAB_SLOPPY] = "sloppy",
  41         [GRAB_AGGRESSIVE] = "aggressive",
  42         NULL
  43 };
  44
  45 /** grab clients that are not yet attached to a filter node */
  46 struct list_head inactive_grab_client_list;
  47
  48 static int max_num_filters(void)
  49 {
  50         int i, ret = 0;
  51         for (i = 0; audio_formats[i]; i++) {
  52                 PARA_INFO_LOG("%s filter chain length: %d\n", audio_formats[i],
  53                         num_filters(i));
  54                 ret = MAX(ret, num_filters(i));
  55         }
  56         PARA_INFO_LOG("maximal filter chain length: %d\n", ret);
  57         return ret;
  58 }
  59
  60 static int gc_write(char *buf, size_t len, struct filter_callback *fcb)
  61 {
  62         struct grab_client *gc = fcb->data;
  63         struct timeval tv = {0, 100};
  64         int ret;
  65
  66 //      PARA_INFO_LOG("writing %d bytes to fd %d\n", len, gc->fd);
  67         fd_set wfds;
  68         do {
  69                 FD_ZERO(&wfds);
  70                 FD_SET(gc->fd, &wfds);
  71                 ret = select(gc->fd + 1, NULL, &wfds, NULL, &tv);
  72         } while (ret == EAGAIN || ret == EINTR);
  73         if (ret != 1) {
  74                 if (gc->mode == GRAB_PEDANTIC)
  75                         return -E_PEDANTIC_GRAB;
  76                 if (gc->mode == GRAB_SLOPPY)
  77                         return 1;
  78         }
  79 rewrite:
  80         ret = write(gc->fd, buf, len);
  81         if (ret < 0) {
  82                 ret = -E_GC_WRITE;
  83                 gc->error = E_GC_WRITE;
  84         } else {
  85                 if (ret != len) {
  86                         if (gc->mode == GRAB_PEDANTIC)
  87                                 return -E_PEDANTIC_GRAB;
  88                         if (gc->mode == GRAB_AGGRESSIVE) {
  89                                 len -= ret;
  90                                 memmove(buf, buf + ret, len);
  91                                 goto rewrite;
  92                         }
  93                 }
  94         }
  95         return ret;
  96 }
  97
  98 static int check_gc_args(struct grab_client *gc)
  99 {
 100         int i;
 101         struct grab_client_args_info *conf = gc->conf;
 102
 103         PARA_INFO_LOG("filter_num: %d\n", gc->conf->filter_num_arg);
 104         for (i = 0; gc_modes[i]; i++)
 105                 if (!strcmp(conf->mode_arg, gc_modes[i]))
 106                         break;
 107         if (!gc_modes[i])
 108                 return -E_INVALID_GRAB_MODE;
 109         gc->mode = i;
 110         if (conf->audio_format_given) {
 111                 gc->audio_format_num = get_audio_format_num(conf->audio_format_arg);
 112                 if (gc->audio_format_num < 0)
 113                         return gc->audio_format_num;
 114         }
 115         if (conf->slot_arg > MAX_STREAM_SLOTS)
 116                 return -E_BAD_GC_SLOT;
 117         if (conf->filter_num_arg <= 0)
 118                 return -E_BAD_GC_FILTER_NUM;
 119         if (conf->audio_format_given) {
 120                 if (num_filters(gc->audio_format_num) < conf->filter_num_arg)
 121                         return -E_BAD_GC_FILTER_NUM;
 122         } else
 123                 if (conf->filter_num_arg > max_num_filters())
 124                         return -E_BAD_GC_FILTER_NUM;
 125
 126         return 1;
 127 }
 128
 129 static void add_inactive_gc(struct grab_client *gc)
 130 {
 131         PARA_INFO_LOG("adding grab client %p (fd %d) to inactive list\n",
 132                 gc, gc->fd);
 133         list_add(&gc->node, &inactive_grab_client_list);
 134 }
 135
 136 static void gc_free(struct grab_client *gc)
 137 {
 138         int i;
 139
 140         for (i = 0; i < gc->argc; i++)
 141                 free(gc->argv[i]);
 142         free(gc->argv);
 143         free(gc->conf);
 144         free(gc);
 145
 146 }
 147
 148 static void gc_close(struct filter_callback *fcb)
 149 {
 150         struct grab_client *gc = fcb->data;
 151
 152         if (gc->conf->one_shot_given || gc->error) {
 153                 PARA_INFO_LOG("closing fd %d (grab client %p)\n", gc->fd, gc);
 154                 del_close_on_fork_list(gc->fd);
 155                 close(gc->fd);
 156                 gc_free(gc);
 157                 /* close on fork ?*/
 158                 return;
 159         }
 160         add_inactive_gc(gc);
 161 }
 162
 163 /**
 164  * move a grab client from the inactive list to a filter node
 165  *
 166  * \param gc the grab client to activate
 167  * \param fn the filter node \a gc gets attached to
 168  *
 169  * \sa filter_node::callbacks, inactive_grab_client_list
 170  */
 171 void activate_grab_client(struct grab_client *gc, struct filter_node *fn)
 172 {
 173         PARA_INFO_LOG("activating %p (fd %d, filter node: %p)\n", gc, gc->fd, fn);
 174         list_del(&gc->node);
 175         list_add(&gc->fcb.node, &fn->callbacks);
 176 }
 177
 178 /**
 179  * activate inactive grab clients if possible
 180  *
 181  * \param slot audiod's slot for the new audio file
 182  * \param audio_format_num the number of the audio format of the new audio file
 183  * \param filter_list the list of activated filters for that new audio file
 184  *
 185  * This is called from audiod.c when the current audio file changes. It loops
 186  * over all inactive grab clients and checks each grab client's configuration
 187  * to determine if the client in question wishes to grab the new stream.  If
 188  * yes, this grab client is moved from the inactive grab client list to an
 189  * appropriate filter_node.
 190  *
 191  * \sa filter_chain_info::filters, inactive_grab_client_list,
 192  * activate_grab_client
 193  */
 194 void activate_inactive_grab_clients(int slot, int audio_format_num,
 195                 struct list_head *filter_list)
 196 {
 197         struct grab_client *gc, *tmp;
 198         int i;
 199         struct filter_node *fn;
 200
 201         list_for_each_entry_safe(gc, tmp, &inactive_grab_client_list, node) {
 202 //              PARA_INFO_LOG("checking inactive grab client %p\n", gc);
 203                 if (gc->conf->slot_arg >= 0 && gc->conf->slot_arg != slot)
 204                         continue;
 205                 if (gc->audio_format_num >= 0 && gc->audio_format_num !=
 206                                 audio_format_num)
 207                         continue;
 208                 if (gc->conf->filter_num_arg >= 0 &&
 209                                 num_filters(gc->audio_format_num)
 210                                 < gc->conf->filter_num_arg)
 211                         continue;
 212                 i = 1;
 213                 list_for_each_entry(fn, filter_list, node) {
 214                         if (gc->conf->filter_num_arg <= 0
 215                                 || i == gc->conf->filter_num_arg)
 216                                 break;
 217                         i++;
 218                 }
 219                 activate_grab_client(gc, fn);
 220         }
 221 }
 222
 223 /**
 224  * check the command line options and allocate a grab_client structure
 225  *
 226  * \param fd the file descriptor of the client
 227  * \param argc the number of command line options
 228  * \param argv pointers to the command line options
 229  * \param err non-zero if an error occured
 230  *
 231  * If the command line options  given by \a argc and \a argv are valid.
 232  * allocate a struct grab_client and initialize it with this valid
 233  * configuration. Moreover, add the new grab client to the inactive list.
 234  *
 235  * \return On success, this function returns a pointer to the newly created
 236  * struct. On errors, it returns NULL and sets \a err appropriately.
 237  *
 238  * \sa grab_client, inactive_grab_client_list, activate_grab_client,
 239  * filter_node::callbacks
 240  */
 241 /*
 242  * argc, argv get freed when com_grab() returns, so we have to make a
 243  * copy.
 244  */
 245 __malloc struct grab_client *grab_client_new(int fd, int argc, char **argv, int *err)
 246 {
 247         int i, ret;
 248         struct grab_client *gc = para_calloc(sizeof(struct grab_client));
 249
 250         gc->conf = para_calloc(sizeof(struct grab_client_args_info));
 251         gc->argc = argc;
 252         gc->argv = para_calloc((argc + 1) * sizeof(char *));
 253
 254         for (i = 0; i < argc; i++) {
 255                 gc->argv[i] = para_strdup(argv[i]);
 256                 PARA_INFO_LOG("argc: %d, argv[%d]: %s\n", argc, i, gc->argv[i]);
 257         }
 258         PARA_INFO_LOG("argv[%d]: %s\n", argc, gc->argv[argc]);
 259         ret = grab_client_cmdline_parser(gc->argc, gc->argv , gc->conf);
 260         *err = -E_GC_SYNTAX;
 261         if (ret)
 262                 goto err_out;
 263         *err = -E_GC_HELP_GIVEN;
 264         if (gc->conf->help_given)
 265                 goto err_out;
 266         *err = -E_GC_VERSION_GIVEN;
 267         if (gc->conf->version_given)
 268                 goto err_out;
 269         *err = check_gc_args(gc);
 270         if (*err < 0)
 271                 goto err_out;
 272         if (gc->conf->input_grab_given) {
 273                 gc->fcb.input_cb = gc_write;
 274                 gc->fcb.output_cb = NULL;
 275         } else {
 276                 gc->fcb.output_cb = gc_write;
 277                 gc->fcb.input_cb = NULL;
 278         }
 279         gc->fd = fd;
 280         gc->fcb.close = gc_close;
 281         gc->fcb.data = gc;
 282         add_inactive_gc(gc);
 283         return gc;
 284 err_out:
 285         for (i = 0; i < argc; i++)
 286                 free(gc->argv[i]);
 287         free(gc->argv);
 288         free(gc->conf);
 289         free(gc);
 290         return NULL;
 291 }
 292
 293 /** initialize the grabbing subsystem.
 294  *
 295  * This has to be called once during startup before any other function from
 296  * grab_client.c may be used. It initializes \a inactive_grab_client_list.
 297  */
 298 void init_grabbing()
 299 {
 300         PARA_INFO_LOG("%s", "grab init\n");
 301         INIT_LIST_HEAD(&inactive_grab_client_list);
 302 }
 303