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Diffstat (limited to 'main/devicestate.c')
-rw-r--r-- | main/devicestate.c | 383 |
1 files changed, 383 insertions, 0 deletions
diff --git a/main/devicestate.c b/main/devicestate.c new file mode 100644 index 000000000..c434ce9a0 --- /dev/null +++ b/main/devicestate.c @@ -0,0 +1,383 @@ +/* + * Asterisk -- An open source telephony toolkit. + * + * Copyright (C) 1999 - 2006, Digium, Inc. + * + * Mark Spencer <markster@digium.com> + * + * See http://www.asterisk.org for more information about + * the Asterisk project. Please do not directly contact + * any of the maintainers of this project for assistance; + * the project provides a web site, mailing lists and IRC + * channels for your use. + * + * This program is free software, distributed under the terms of + * the GNU General Public License Version 2. See the LICENSE file + * at the top of the source tree. + */ + +/*! \file + * + * \brief Device state management + * + * \author Mark Spencer <markster@digium.com> + */ + +#include "asterisk.h" + +ASTERISK_FILE_VERSION(__FILE__, "$Revision$") + +#include <sys/types.h> +#include <unistd.h> +#include <stdlib.h> +#include <string.h> +#include <stdio.h> + +#include "asterisk/channel.h" +#include "asterisk/utils.h" +#include "asterisk/lock.h" +#include "asterisk/linkedlists.h" +#include "asterisk/logger.h" +#include "asterisk/devicestate.h" +#include "asterisk/pbx.h" +#include "asterisk/app.h" +#include "asterisk/options.h" + +/*! \brief Device state strings for printing */ +static const char *devstatestring[] = { + /* 0 AST_DEVICE_UNKNOWN */ "Unknown", /*!< Valid, but unknown state */ + /* 1 AST_DEVICE_NOT_INUSE */ "Not in use", /*!< Not used */ + /* 2 AST_DEVICE IN USE */ "In use", /*!< In use */ + /* 3 AST_DEVICE_BUSY */ "Busy", /*!< Busy */ + /* 4 AST_DEVICE_INVALID */ "Invalid", /*!< Invalid - not known to Asterisk */ + /* 5 AST_DEVICE_UNAVAILABLE */ "Unavailable", /*!< Unavailable (not registred) */ + /* 6 AST_DEVICE_RINGING */ "Ringing", /*!< Ring, ring, ring */ + /* 7 AST_DEVICE_RINGINUSE */ "Ring+Inuse", /*!< Ring and in use */ + /* 8 AST_DEVICE_ONHOLD */ "On Hold" /*!< On Hold */ +}; + +/*! \brief A device state provider (not a channel) */ +struct devstate_prov { + char label[40]; + ast_devstate_prov_cb_type callback; + AST_LIST_ENTRY(devstate_prov) list; +}; + +/*! \brief A list of providers */ +static AST_LIST_HEAD_STATIC(devstate_provs, devstate_prov); + +/*! \brief A device state watcher (callback) */ +struct devstate_cb { + void *data; + ast_devstate_cb_type callback; + AST_LIST_ENTRY(devstate_cb) list; +}; + +/*! \brief A device state watcher list */ +static AST_LIST_HEAD_STATIC(devstate_cbs, devstate_cb); + +struct state_change { + AST_LIST_ENTRY(state_change) list; + char device[1]; +}; + +/*! \brief The state change queue. State changes are queued + for processing by a separate thread */ +static AST_LIST_HEAD_STATIC(state_changes, state_change); + +/*! \brief The device state change notification thread */ +static pthread_t change_thread = AST_PTHREADT_NULL; + +/*! \brief Flag for the queue */ +static ast_cond_t change_pending; + +/* Forward declarations */ +static int getproviderstate(const char *provider, const char *address); + +/*! \brief Find devicestate as text message for output */ +const char *devstate2str(int devstate) +{ + return devstatestring[devstate]; +} + +/*! \brief Find out if device is active in a call or not + \note find channels with the device's name in it + This function is only used for channels that does not implement + devicestate natively +*/ +int ast_parse_device_state(const char *device) +{ + struct ast_channel *chan; + char match[AST_CHANNEL_NAME]; + int res; + + ast_copy_string(match, device, sizeof(match)-1); + strcat(match, "-"); + chan = ast_get_channel_by_name_prefix_locked(match, strlen(match)); + + if (!chan) + return AST_DEVICE_UNKNOWN; + + if (chan->_state == AST_STATE_RINGING) + res = AST_DEVICE_RINGING; + else + res = AST_DEVICE_INUSE; + + ast_channel_unlock(chan); + + return res; +} + +/*! \brief Check device state through channel specific function or generic function */ +int ast_device_state(const char *device) +{ + char *buf; + char *number; + const struct ast_channel_tech *chan_tech; + int res = 0; + /*! \brief Channel driver that provides device state */ + char *tech; + /*! \brief Another provider of device state */ + char *provider = NULL; + + buf = ast_strdupa(device); + tech = strsep(&buf, "/"); + number = buf; + if (!number) { + provider = strsep(&tech, ":"); + if (!provider) + return AST_DEVICE_INVALID; + /* We have a provider */ + number = tech; + tech = NULL; + } + + if (provider) { + if(option_debug > 2) + ast_log(LOG_DEBUG, "Checking if I can find provider for \"%s\" - number: %s\n", provider, number); + return getproviderstate(provider, number); + } + if (option_debug > 3) + ast_log(LOG_DEBUG, "No provider found, checking channel drivers for %s - %s\n", tech, number); + + chan_tech = ast_get_channel_tech(tech); + if (!chan_tech) + return AST_DEVICE_INVALID; + + if (!chan_tech->devicestate) /* Does the channel driver support device state notification? */ + return ast_parse_device_state(device); /* No, try the generic function */ + else { + res = chan_tech->devicestate(number); /* Ask the channel driver for device state */ + if (res == AST_DEVICE_UNKNOWN) { + res = ast_parse_device_state(device); + /* at this point we know the device exists, but the channel driver + could not give us a state; if there is no channel state available, + it must be 'not in use' + */ + if (res == AST_DEVICE_UNKNOWN) + res = AST_DEVICE_NOT_INUSE; + return res; + } else + return res; + } +} + +/*! \brief Add device state provider */ +int ast_devstate_prov_add(const char *label, ast_devstate_prov_cb_type callback) +{ + struct devstate_prov *devprov; + + if (!callback || !(devprov = ast_calloc(1, sizeof(*devprov)))) + return -1; + + devprov->callback = callback; + ast_copy_string(devprov->label, label, sizeof(devprov->label)); + + AST_LIST_LOCK(&devstate_provs); + AST_LIST_INSERT_HEAD(&devstate_provs, devprov, list); + AST_LIST_UNLOCK(&devstate_provs); + + return 0; +} + +/*! \brief Remove device state provider */ +void ast_devstate_prov_del(const char *label) +{ + struct devstate_prov *devcb; + + AST_LIST_LOCK(&devstate_provs); + AST_LIST_TRAVERSE_SAFE_BEGIN(&devstate_provs, devcb, list) { + if (!strcasecmp(devcb->label, label)) { + AST_LIST_REMOVE_CURRENT(&devstate_provs, list); + free(devcb); + break; + } + } + AST_LIST_TRAVERSE_SAFE_END; + AST_LIST_UNLOCK(&devstate_provs); +} + +/*! \brief Get provider device state */ +static int getproviderstate(const char *provider, const char *address) +{ + struct devstate_prov *devprov; + int res = AST_DEVICE_INVALID; + + + AST_LIST_LOCK(&devstate_provs); + AST_LIST_TRAVERSE_SAFE_BEGIN(&devstate_provs, devprov, list) { + if(option_debug > 4) + ast_log(LOG_DEBUG, "Checking provider %s with %s\n", devprov->label, provider); + + if (!strcasecmp(devprov->label, provider)) { + res = devprov->callback(address); + break; + } + } + AST_LIST_TRAVERSE_SAFE_END; + AST_LIST_UNLOCK(&devstate_provs); + return res; +} + +/*! \brief Add device state watcher */ +int ast_devstate_add(ast_devstate_cb_type callback, void *data) +{ + struct devstate_cb *devcb; + + if (!callback || !(devcb = ast_calloc(1, sizeof(*devcb)))) + return -1; + + devcb->data = data; + devcb->callback = callback; + + AST_LIST_LOCK(&devstate_cbs); + AST_LIST_INSERT_HEAD(&devstate_cbs, devcb, list); + AST_LIST_UNLOCK(&devstate_cbs); + + return 0; +} + +/*! \brief Remove device state watcher */ +void ast_devstate_del(ast_devstate_cb_type callback, void *data) +{ + struct devstate_cb *devcb; + + AST_LIST_LOCK(&devstate_cbs); + AST_LIST_TRAVERSE_SAFE_BEGIN(&devstate_cbs, devcb, list) { + if ((devcb->callback == callback) && (devcb->data == data)) { + AST_LIST_REMOVE_CURRENT(&devstate_cbs, list); + free(devcb); + break; + } + } + AST_LIST_TRAVERSE_SAFE_END; + AST_LIST_UNLOCK(&devstate_cbs); +} + +/*! \brief Notify callback watchers of change, and notify PBX core for hint updates + Normally executed within a separate thread +*/ +static void do_state_change(const char *device) +{ + int state; + struct devstate_cb *devcb; + + state = ast_device_state(device); + if (option_debug > 2) + ast_log(LOG_DEBUG, "Changing state for %s - state %d (%s)\n", device, state, devstate2str(state)); + + AST_LIST_LOCK(&devstate_cbs); + AST_LIST_TRAVERSE(&devstate_cbs, devcb, list) + devcb->callback(device, state, devcb->data); + AST_LIST_UNLOCK(&devstate_cbs); + + ast_hint_state_changed(device); +} + +static int __ast_device_state_changed_literal(char *buf) +{ + char *device, *tmp; + struct state_change *change; + + if (option_debug > 2) + ast_log(LOG_DEBUG, "Notification of state change to be queued on device/channel %s\n", buf); + + device = buf; + if ((tmp = strrchr(device, '-'))) + *tmp = '\0'; + + + + if (change_thread == AST_PTHREADT_NULL || !(change = ast_calloc(1, sizeof(*change) + strlen(device)))) { + /* we could not allocate a change struct, or */ + /* there is no background thread, so process the change now */ + do_state_change(device); + } else { + /* queue the change */ + strcpy(change->device, device); + AST_LIST_LOCK(&state_changes); + AST_LIST_INSERT_TAIL(&state_changes, change, list); + if (AST_LIST_FIRST(&state_changes) == change) + /* the list was empty, signal the thread */ + ast_cond_signal(&change_pending); + AST_LIST_UNLOCK(&state_changes); + } + + return 1; +} + +int ast_device_state_changed_literal(const char *dev) +{ + char *buf; + buf = ast_strdupa(dev); + return __ast_device_state_changed_literal(buf); +} + +/*! \brief Accept change notification, add it to change queue */ +int ast_device_state_changed(const char *fmt, ...) +{ + char buf[AST_MAX_EXTENSION]; + va_list ap; + + va_start(ap, fmt); + vsnprintf(buf, sizeof(buf), fmt, ap); + va_end(ap); + return __ast_device_state_changed_literal(buf); +} + +/*! \brief Go through the dev state change queue and update changes in the dev state thread */ +static void *do_devstate_changes(void *data) +{ + struct state_change *cur; + + AST_LIST_LOCK(&state_changes); + for(;;) { + /* the list lock will _always_ be held at this point in the loop */ + cur = AST_LIST_REMOVE_HEAD(&state_changes, list); + if (cur) { + /* we got an entry, so unlock the list while we process it */ + AST_LIST_UNLOCK(&state_changes); + do_state_change(cur->device); + free(cur); + AST_LIST_LOCK(&state_changes); + } else { + /* there was no entry, so atomically unlock the list and wait for + the condition to be signalled (returns with the lock held) */ + ast_cond_wait(&change_pending, &state_changes.lock); + } + } + + return NULL; +} + +/*! \brief Initialize the device state engine in separate thread */ +int ast_device_state_engine_init(void) +{ + ast_cond_init(&change_pending, NULL); + if (ast_pthread_create(&change_thread, NULL, do_devstate_changes, NULL) < 0) { + ast_log(LOG_ERROR, "Unable to start device state change thread.\n"); + return -1; + } + + return 0; +} |