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