grab_client.c

   1 /*
   2  * Copyright (C) 2006-2007 Andre Noll <maan@systemlinux.org>
   3  *
   4  * Licensed under the GPL v2. For licencing details see COPYING.
   5  */
   6
   7 /**
   8  * \file grab_client.c Functions for grabbing the stream at any position
   9  * in a filter chain.
  10  *
  11  * \sa filter_chain filter_chain_info filter.
  12  */
  13
  14 #include <sys/types.h>
  15 #include <dirent.h>
  16
  17 #include "para.h"
  18 #include "grab_client.cmdline.h"
  19 #include "list.h"
  20 #include "sched.h"
  21 #include "filter.h"
  22 #include "grab_client.h"
  23 #include "audiod.h"
  24 #include "error.h"
  25 #include "string.h"
  26 #include "fd.h"
  27 #include "crypt.h"
  28
  29 /** Grab clients that are not yet attached to a filter node. */
  30 struct list_head inactive_grab_client_list;
  31
  32 static int max_num_filters(void)
  33 {
  34         int i, ret = 0;
  35         for (i = 0; audio_formats[i]; i++) {
  36                 PARA_INFO_LOG("%s filter chain length: %d\n", audio_formats[i],
  37                         num_filters(i));
  38                 ret = PARA_MAX(ret, num_filters(i));
  39         }
  40         PARA_INFO_LOG("maximal filter chain length: %d\n", ret);
  41         return ret;
  42 }
  43
  44 static int gc_write(char *buf, size_t len, struct filter_callback *fcb)
  45 {
  46         struct grab_client *gc = fcb->data;
  47         struct timeval tv = {0, 100};
  48         int ret;
  49
  50 //      PARA_INFO_LOG("writing %d bytes to fd %d\n", len, gc->fd);
  51         fd_set wfds;
  52         FD_ZERO(&wfds);
  53         FD_SET(gc->fd, &wfds);
  54         ret = para_select(gc->fd + 1, NULL, &wfds, &tv);
  55         if (ret <= 0) {
  56                 if (gc->mode == GRAB_PEDANTIC)
  57                         return -E_PEDANTIC_GRAB;
  58                 if (gc->mode == GRAB_SLOPPY)
  59                         return 1;
  60         }
  61 rewrite:
  62         ret = write(gc->fd, buf, len);
  63         if (ret < 0) {
  64                 ret = -E_GC_WRITE;
  65                 gc->error = E_GC_WRITE;
  66         } else {
  67                 if (ret != len) {
  68                         if (gc->mode == GRAB_PEDANTIC)
  69                                 return -E_PEDANTIC_GRAB;
  70                         if (gc->mode == GRAB_AGGRESSIVE) {
  71                                 len -= ret;
  72                                 memmove(buf, buf + ret, len);
  73                                 goto rewrite;
  74                         }
  75                 }
  76         }
  77         return ret;
  78 }
  79
  80 /* TODO: gengetopt can handle the grab client modes */
  81 static int check_gc_args(struct grab_client *gc)
  82 {
  83         int i;
  84         struct grab_client_args_info *c = gc->conf;
  85         char **mv = grab_client_cmdline_parser_mode_values;
  86
  87         PARA_INFO_LOG("filter_num: %d\n", c->filter_num_arg);
  88         for (i = 0; mv[i]; i++)
  89                 if (!strcmp(c->mode_arg, mv[i]))
  90                         break;
  91         if (!mv[i])
  92                 return -E_GC_SYNTAX;
  93         gc->mode = i;
  94         gc->audio_format_num = -1;
  95         if (c->audio_format_given) {
  96                 gc->audio_format_num = get_audio_format_num(c->audio_format_arg);
  97                 if (gc->audio_format_num < 0)
  98                         return gc->audio_format_num;
  99         }
 100         if (c->slot_arg > MAX_STREAM_SLOTS)
 101                 return -E_BAD_GC_SLOT;
 102         if (c->filter_num_arg <= 0)
 103                 return -E_BAD_GC_FILTER_NUM;
 104         if (c->audio_format_given) {
 105                 if (num_filters(gc->audio_format_num) < c->filter_num_arg)
 106                         return -E_BAD_GC_FILTER_NUM;
 107         } else
 108                 if (c->filter_num_arg > max_num_filters())
 109                         return -E_BAD_GC_FILTER_NUM;
 110
 111         return 1;
 112 }
 113
 114 static void add_inactive_gc(struct grab_client *gc)
 115 {
 116         PARA_INFO_LOG("adding grab client %p (fd %d) to inactive list\n",
 117                 gc, gc->fd);
 118         para_list_add(&gc->node, &inactive_grab_client_list);
 119 }
 120
 121 static void gc_free(struct grab_client *gc)
 122 {
 123         int i;
 124
 125         for (i = 0; i < gc->argc; i++)
 126                 free(gc->argv[i]);
 127         free(gc->argv);
 128         free(gc->conf);
 129         free(gc);
 130
 131 }
 132
 133 static void gc_close(struct filter_callback *fcb)
 134 {
 135         struct grab_client *gc = fcb->data;
 136
 137         if (gc->conf->one_shot_given || gc->error) {
 138                 PARA_INFO_LOG("closing fd %d (grab client %p)\n", gc->fd, gc);
 139                 close(gc->fd);
 140                 gc_free(gc);
 141                 /* close on fork ?*/
 142                 return;
 143         }
 144         add_inactive_gc(gc);
 145 }
 146
 147 /**
 148  * Move a grab client from the inactive list to a filter node.
 149  *
 150  * \param gc The grab client to activate.
 151  * \param fn The filter node \a gc gets attached to.
 152  *
 153  * \sa filter_node::callbacks, inactive_grab_client_list.
 154  */
 155 void activate_grab_client(struct grab_client *gc, struct filter_node *fn)
 156 {
 157         PARA_INFO_LOG("activating %p (fd %d, filter node: %p)\n", gc, gc->fd, fn);
 158         list_del(&gc->node);
 159         para_list_add(&gc->fcb.node, &fn->callbacks);
 160 }
 161
 162 /**
 163  * Activate inactive grab clients if possible.
 164  *
 165  * \param slot_num Audiod's slot for the new audio file.
 166  * \param audio_format_num The number of the audio format of the new audio file.
 167  * \param filter_list The list of activated filters for that new audio file.
 168  *
 169  * This is called from audiod.c when the current audio file changes. It loops
 170  * over all inactive grab clients and checks each grab client's configuration
 171  * to determine if the client in question wishes to grab the new stream.  If
 172  * yes, this grab client is moved from the inactive grab client list to an
 173  * appropriate filter_node.
 174  *
 175  * \sa filter_chain_info::filters, inactive_grab_client_list,
 176  * activate_grab_client.
 177  */
 178 void activate_inactive_grab_clients(int slot_num, int audio_format_num,
 179                 struct list_head *filter_list)
 180 {
 181         struct grab_client *gc, *tmp;
 182         int i;
 183         struct filter_node *fn;
 184
 185         list_for_each_entry_safe(gc, tmp, &inactive_grab_client_list, node) {
 186 //              PARA_INFO_LOG("checking inactive grab client %p\n", gc);
 187                 if (gc->conf->slot_arg >= 0 && gc->conf->slot_arg != slot_num)
 188                         continue;
 189                 if (gc->audio_format_num >= 0 && gc->audio_format_num !=
 190                                 audio_format_num)
 191                         continue;
 192                 if (gc->conf->filter_num_arg >= 0 &&
 193                                 num_filters(gc->audio_format_num)
 194                                 < gc->conf->filter_num_arg)
 195                         continue;
 196                 i = 1;
 197                 list_for_each_entry(fn, filter_list, node) {
 198                         if (gc->conf->filter_num_arg <= 0
 199                                 || i == gc->conf->filter_num_arg)
 200                                 break;
 201                         i++;
 202                 }
 203                 activate_grab_client(gc, fn);
 204         }
 205 }
 206
 207 /**
 208  * Check the command line options and allocate a grab_client structure.
 209  *
 210  * \param fd The file descriptor of the client.
 211  * \param line The command line.
 212  * \param err Non-zero if an error occurred.
 213  *
 214  * If the command line options given by \a argc and \a argv are valid.
 215  * allocate a struct grab_client and initialize it with this valid
 216  * configuration. Moreover, add the new grab client to the inactive list.
 217  *
 218  * \return On success, this function returns a pointer to the newly created
 219  * struct. On errors, it returns NULL and sets \a err appropriately.
 220  *
 221  * \sa grab_client, inactive_grab_client_list, activate_grab_client,
 222  * filter_node::callbacks.
 223  */
 224 /*
 225  * argc, argv get freed when com_grab() returns, so we have to make a
 226  * copy.
 227  */
 228 struct grab_client *grab_client_new(int fd, char *line, int *err)
 229 {
 230         int ret;
 231         struct grab_client *gc = para_calloc(sizeof(struct grab_client));
 232
 233         gc->conf = para_calloc(sizeof(struct grab_client_args_info));
 234
 235         ret = grab_client_cmdline_parser_string(line, gc->conf, "grab");
 236         *err = -E_GC_SYNTAX;
 237         if (ret)
 238                 goto err_out;
 239         *err = -E_GC_HELP_GIVEN;
 240         if (gc->conf->help_given)
 241                 goto err_out;
 242         *err = -E_GC_VERSION_GIVEN;
 243         if (gc->conf->version_given)
 244                 goto err_out;
 245         *err = check_gc_args(gc);
 246         if (*err < 0)
 247                 goto err_out;
 248         if (gc->conf->input_grab_given) {
 249                 gc->fcb.input_cb = gc_write;
 250                 gc->fcb.output_cb = NULL;
 251         } else {
 252                 gc->fcb.output_cb = gc_write;
 253                 gc->fcb.input_cb = NULL;
 254         }
 255         gc->fd = fd;
 256         gc->fcb.close = gc_close;
 257         gc->fcb.data = gc;
 258         add_inactive_gc(gc);
 259         return gc;
 260 err_out:
 261         free(gc->conf);
 262         free(gc);
 263         return NULL;
 264 }
 265
 266 /**
 267  * Initialize the grabbing subsystem.
 268  *
 269  * This has to be called once during startup before any other function from
 270  * grab_client.c may be used. It initializes \a inactive_grab_client_list.
 271  */
 272 void init_grabbing(void)
 273 {
 274         PARA_INFO_LOG("%s", "grab init\n");
 275         INIT_LIST_HEAD(&inactive_grab_client_list);
 276 }