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