grab_client.c

   1 /*
   2  * Copyright (C) 2006-2009 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 "ggo.h"
  22 #include "filter.h"
  23 #include "grab_client.h"
  24 #include "audiod.h"
  25 #include "error.h"
  26 #include "string.h"
  27 #include "fd.h"
  28 #include "crypt.h"
  29
  30 /** Grab clients that are not yet attached to a filter node. */
  31 struct list_head inactive_grab_client_list;
  32
  33 static int max_num_filters(void)
  34 {
  35         int i, ret = 0;
  36         for (i = 0; audio_formats[i]; i++) {
  37                 PARA_INFO_LOG("%s filter chain length: %d\n", audio_formats[i],
  38                         num_filters(i));
  39                 ret = PARA_MAX(ret, num_filters(i));
  40         }
  41         PARA_INFO_LOG("maximal filter chain length: %d\n", ret);
  42         return ret;
  43 }
  44
  45 static int gc_write(char *buf, size_t len, struct filter_callback *fcb)
  46 {
  47         struct grab_client *gc = fcb->data;
  48         struct timeval tv = {0, 100};
  49         int ret;
  50
  51 //      PARA_INFO_LOG("writing %d bytes to fd %d\n", len, gc->fd);
  52         fd_set wfds;
  53         FD_ZERO(&wfds);
  54         FD_SET(gc->fd, &wfds);
  55         ret = para_select(gc->fd + 1, NULL, &wfds, &tv);
  56         if (ret <= 0) {
  57                 if (gc->mode == GRAB_PEDANTIC)
  58                         return -E_PEDANTIC_GRAB;
  59                 if (gc->mode == GRAB_SLOPPY)
  60                         return 1;
  61         }
  62 rewrite:
  63         ret = write(gc->fd, buf, len);
  64         if (ret < 0) {
  65                 ret = -E_GC_WRITE;
  66                 gc->error = E_GC_WRITE;
  67         } else {
  68                 if (ret != len) {
  69                         if (gc->mode == GRAB_PEDANTIC)
  70                                 return -E_PEDANTIC_GRAB;
  71                         if (gc->mode == GRAB_AGGRESSIVE) {
  72                                 len -= ret;
  73                                 memmove(buf, buf + ret, len);
  74                                 goto rewrite;
  75                         }
  76                 }
  77         }
  78         return ret;
  79 }
  80
  81 /* TODO: gengetopt can handle the grab client modes */
  82 static int check_gc_args(struct grab_client *gc)
  83 {
  84         int i;
  85         struct grab_client_args_info *c = gc->conf;
  86         const char **mv = grab_client_cmdline_parser_mode_values;
  87
  88         PARA_INFO_LOG("filter_num: %d\n", c->filter_num_arg);
  89         for (i = 0; mv[i]; i++)
  90                 if (!strcmp(c->mode_arg, mv[i]))
  91                         break;
  92         if (!mv[i])
  93                 return -E_GC_SYNTAX;
  94         gc->mode = i;
  95         gc->audio_format_num = -1;
  96         if (c->audio_format_given) {
  97                 gc->audio_format_num = get_audio_format_num(c->audio_format_arg);
  98                 if (gc->audio_format_num < 0)
  99                         return gc->audio_format_num;
 100         }
 101         if (c->slot_arg >= MAX_STREAM_SLOTS)
 102                 return -E_BAD_GC_SLOT;
 103         if (c->filter_num_arg < 0)
 104                 return -E_BAD_GC_FILTER_NUM;
 105         if (c->audio_format_given) {
 106                 if (num_filters(gc->audio_format_num) <= c->filter_num_arg)
 107                         return -E_BAD_GC_FILTER_NUM;
 108         } else
 109                 if (c->filter_num_arg >= max_num_filters())
 110                         return -E_BAD_GC_FILTER_NUM;
 111
 112         return 1;
 113 }
 114
 115 static void add_inactive_gc(struct grab_client *gc)
 116 {
 117         PARA_INFO_LOG("adding grab client %p (fd %d) to inactive list\n",
 118                 gc, gc->fd);
 119         para_list_add(&gc->node, &inactive_grab_client_list);
 120 }
 121
 122 static void gc_free(struct grab_client *gc)
 123 {
 124         int i;
 125
 126         for (i = 0; i < gc->argc; i++)
 127                 free(gc->argv[i]);
 128         free(gc->argv);
 129         free(gc->conf);
 130         free(gc);
 131
 132 }
 133
 134 static void gc_close(struct filter_callback *fcb)
 135 {
 136         struct grab_client *gc = fcb->data;
 137
 138         if (gc->conf->one_shot_given || gc->error) {
 139                 PARA_INFO_LOG("closing fd %d (grab client %p)\n", gc->fd, gc);
 140                 close(gc->fd);
 141                 gc_free(gc);
 142                 /* close on fork ?*/
 143                 return;
 144         }
 145         add_inactive_gc(gc);
 146 }
 147
 148 /**
 149  * Move a grab client from the inactive list to a filter node.
 150  *
 151  * \param gc The grab client to activate.
 152  * \param fn The filter node \a gc gets attached to.
 153  *
 154  * \sa filter_node::callbacks, inactive_grab_client_list.
 155  */
 156 void activate_grab_client(struct grab_client *gc, struct filter_node *fn)
 157 {
 158         PARA_INFO_LOG("activating %p (fd %d, filter node: %p)\n", gc, gc->fd, fn);
 159         list_del(&gc->node);
 160         para_list_add(&gc->fcb.node, &fn->callbacks);
 161 }
 162
 163 /**
 164  * Activate inactive grab clients if possible.
 165  *
 166  * \param slot_num Audiod's slot for the new audio file.
 167  * \param audio_format_num The number of the audio format of the new audio file.
 168  * \param fc The filter chain containing the activated filters.
 169  *
 170  * This is called from audiod.c when the current audio file changes. It loops
 171  * over all inactive grab clients and checks each grab client's configuration
 172  * to determine if the client in question wishes to grab the new stream.  If
 173  * yes, this grab client is moved from the inactive grab client list to an
 174  * appropriate filter_node.
 175  *
 176  * \sa filter_chain_info::filters, inactive_grab_client_list,
 177  * activate_grab_client.
 178  */
 179 void activate_inactive_grab_clients(int slot_num, int audio_format_num,
 180                 struct filter_chain *fc)
 181 {
 182         struct grab_client *gc, *tmp;
 183         int filter_num;
 184         struct filter_node *fn;
 185
 186         list_for_each_entry_safe(gc, tmp, &inactive_grab_client_list, node) {
 187 //              PARA_INFO_LOG("checking inactive grab client %p\n", gc);
 188                 if (gc->conf->slot_arg >= 0 && gc->conf->slot_arg != slot_num)
 189                         continue;
 190                 if (gc->audio_format_num >= 0 && gc->audio_format_num !=
 191                                 audio_format_num)
 192                         continue;
 193                 filter_num = gc->conf->filter_num_arg;
 194                 if (filter_num >= num_filters(gc->audio_format_num))
 195                         continue;
 196                 fn = fc->filter_nodes + filter_num;
 197                 activate_grab_client(gc, fn);
 198         }
 199 }
 200
 201 /**
 202  * Check the command line options and allocate a grab_client structure.
 203  *
 204  * \param fd The file descriptor of the client.
 205  * \param line The command line.
 206  * \param err Non-zero if an error occurred.
 207  *
 208  * If the command line options given by \a argc and \a argv are valid.
 209  * allocate a struct grab_client and initialize it with this valid
 210  * configuration. Moreover, add the new grab client to the inactive list.
 211  *
 212  * \return On success, this function returns a pointer to the newly created
 213  * struct. On errors, it returns NULL and sets \a err appropriately.
 214  *
 215  * \sa grab_client, inactive_grab_client_list, activate_grab_client,
 216  * filter_node::callbacks.
 217  */
 218 /*
 219  * argc, argv get freed when com_grab() returns, so we have to make a
 220  * copy.
 221  */
 222 struct grab_client *grab_client_new(int fd, char *line, int *err)
 223 {
 224         int ret;
 225         struct grab_client *gc = para_calloc(sizeof(struct grab_client));
 226
 227         gc->conf = para_calloc(sizeof(struct grab_client_args_info));
 228
 229         ret = grab_client_cmdline_parser_string(line, gc->conf, "grab");
 230         *err = -E_GC_SYNTAX;
 231         if (ret)
 232                 goto err_out;
 233         *err = -E_GC_HELP_GIVEN;
 234         if (gc->conf->help_given)
 235                 goto err_out;
 236         *err = -E_GC_VERSION_GIVEN;
 237         if (gc->conf->version_given)
 238                 goto err_out;
 239         *err = check_gc_args(gc);
 240         if (*err < 0)
 241                 goto err_out;
 242         if (gc->conf->input_grab_given) {
 243                 gc->fcb.input_cb = gc_write;
 244                 gc->fcb.output_cb = NULL;
 245         } else {
 246                 gc->fcb.output_cb = gc_write;
 247                 gc->fcb.input_cb = NULL;
 248         }
 249         gc->fd = fd;
 250         gc->fcb.close = gc_close;
 251         gc->fcb.data = gc;
 252         add_inactive_gc(gc);
 253         return gc;
 254 err_out:
 255         free(gc->conf);
 256         free(gc);
 257         return NULL;
 258 }
 259
 260 /**
 261  * Initialize the grabbing subsystem.
 262  *
 263  * This has to be called once during startup before any other function from
 264  * grab_client.c may be used. It initializes \a inactive_grab_client_list.
 265  */
 266 void init_grabbing(void)
 267 {
 268         PARA_INFO_LOG("grab init\n");
 269         INIT_LIST_HEAD(&inactive_grab_client_list);
 270 }