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;
+}