grab_client.c

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