From 745cbab5017fbc32e1dbe0c1ce781205632708c2 Mon Sep 17 00:00:00 2001
From: Alexei Gradinari <alex2grad@gmail.com>
Date: Tue, 21 May 2019 15:53:47 -0400
Subject: [PATCH] app_blind_transfer: new application BlindTransfer

BlindTransfer redirects all channels currently bridged to the
caller channel to the specified destination.

This application can be useful with Custom Dynamic Features.
For example to make blind transfer to a predefined number.

features.conf
;;;
[applicationmap]
my_blindxfer => *6,self,GoSub,"my_blindxfer,s,1",default
;;;

extensions.conf
;;;
[globals]
DYNAMIC_FEATURES=my_blindxfer

[my_blindxfer]
exten => s,1,BlindTransfer(1234567890,default)
   same => n,Return()
;;;

This application also can be used to completly redefine Blind transfer
feature using dialplan. For example:

features.conf
;;;
[featuremap]
blindxfer =>

[applicationmap]
custom_blindxfer => ##,self,GoSub,"custom_blindxfer,s,1",default
;;;

extensions.conf
;;;
[globals]
DYNAMIC_FEATURES=custom_blindxfer

[custom_blindxfer]
exten => s,1,
   same => n,Playback(pbx-transfer)
   same => n,Read(dest,dial,10,i,3,3)
   same => n,BlindTransfer(${dest},default)
   same => n,Return()
;;;

Change-Id: I9d55e7f69ccfd4472dec00d62771d6de8803215a
---
 apps/app_blind_transfer.c                  | 137 +++++++++++++++++++++
 doc/CHANGES-staging/app_blind_transfer.txt |   4 +
 menuselect/example_menuselect-tree         |   2 +
 menuselect/test/menuselect-tree            |   2 +
 4 files changed, 145 insertions(+)
 create mode 100644 apps/app_blind_transfer.c
 create mode 100644 doc/CHANGES-staging/app_blind_transfer.txt

diff --git a/apps/app_blind_transfer.c b/apps/app_blind_transfer.c
new file mode 100644
index 0000000000..1c3fbb27cb
--- /dev/null
+++ b/apps/app_blind_transfer.c
@@ -0,0 +1,137 @@
+/*
+ * Asterisk -- An open source telephony toolkit.
+ *
+ * Copyright (C) 2019, Alexei Gradinari
+ *
+ * Alexei Gradinari <alex2grad@gmail.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 Blind transfer by caller channel
+ *
+ * \author Alexei Gradinari <alex2grad@gmail.com>
+ *
+ * \ingroup applications
+ */
+
+/*** MODULEINFO
+	<support_level>extended</support_level>
+ ***/
+
+#include "asterisk.h"
+
+#include "asterisk/pbx.h"
+#include "asterisk/module.h"
+#include "asterisk/app.h"
+#include "asterisk/channel.h"
+#include "asterisk/bridge.h"
+
+/*** DOCUMENTATION
+	<application name="BlindTransfer" language="en_US">
+		<synopsis>
+			Blind transfer channel(s) to the extension and context provided
+		</synopsis>
+		<syntax>
+			<parameter name="exten" required="true">
+				<para>Specify extension.</para>
+			</parameter>
+			<parameter name="context">
+				<para>Optionally specify a context.
+				By default, Asterisk will use the caller channel context.</para>
+			</parameter>
+		</syntax>
+		<description>
+			<para>Redirect all channels currently bridged to the caller channel to the
+			specified destination.</para>
+			<para>The result of the application will be reported in the <variable>BLINDTRANSFERSTATUS</variable>
+			channel variable:</para>
+			<variablelist>
+				<variable name="BLINDTRANSFERSTATUS">
+					<value name="SUCCESS">
+						Transfer succeeded.
+					</value>
+					<value name="FAILURE">
+						Transfer failed.
+					</value>
+					<value name="INVALID">
+						Transfer invalid.
+					</value>
+					<value name="NOTPERMITTED">
+						Transfer not permitted.
+					</value>
+				</variable>
+			</variablelist>
+		</description>
+	</application>
+ ***/
+
+static const char * const app = "BlindTransfer";
+
+static int blind_transfer_exec(struct ast_channel *chan, const char *data)
+{
+	char *exten = NULL;
+	char *context = NULL;
+	char *parse;
+	AST_DECLARE_APP_ARGS(args,
+		AST_APP_ARG(exten);
+		AST_APP_ARG(context);
+	);
+
+	if (ast_strlen_zero((char *)data)) {
+		ast_log(LOG_WARNING, "%s requires an argument (exten)\n", app);
+		pbx_builtin_setvar_helper(chan, "BLINDTRANSFERSTATUS", "FAILURE");
+		return 0;
+	}
+
+	parse = ast_strdupa(data);
+	AST_STANDARD_APP_ARGS(args, parse);
+
+	exten = args.exten;
+	if (ast_strlen_zero(args.context)) {
+		context = (char *)ast_channel_context(chan);
+	} else {
+		context = args.context;
+	}
+
+	switch (ast_bridge_transfer_blind(1, chan, exten, context, NULL, NULL)) {
+		case AST_BRIDGE_TRANSFER_NOT_PERMITTED:
+			pbx_builtin_setvar_helper(chan, "BLINDTRANSFERSTATUS", "NOTPERMITTED");
+			break;
+		case AST_BRIDGE_TRANSFER_INVALID:
+			pbx_builtin_setvar_helper(chan, "BLINDTRANSFERSTATUS", "INVALID");
+			break;
+		case AST_BRIDGE_TRANSFER_FAIL:
+			pbx_builtin_setvar_helper(chan, "BLINDTRANSFERSTATUS", "FAILURE");
+			break;
+		case AST_BRIDGE_TRANSFER_SUCCESS:
+			pbx_builtin_setvar_helper(chan, "BLINDTRANSFERSTATUS", "SUCCESS");
+			break;
+		default:
+			pbx_builtin_setvar_helper(chan, "BLINDTRANSFERSTATUS", "FAILURE");
+        }
+
+	return 0;
+}
+
+static int unload_module(void)
+{
+	return ast_unregister_application(app);
+}
+
+static int load_module(void)
+{
+	return ast_register_application_xml(app, blind_transfer_exec);
+}
+
+AST_MODULE_INFO_STANDARD(ASTERISK_GPL_KEY, "Blind transfer channel to the given destination");
diff --git a/doc/CHANGES-staging/app_blind_transfer.txt b/doc/CHANGES-staging/app_blind_transfer.txt
new file mode 100644
index 0000000000..dc86df0031
--- /dev/null
+++ b/doc/CHANGES-staging/app_blind_transfer.txt
@@ -0,0 +1,4 @@
+Subject: BlindTransfer
+
+A new application, this will redirect all channels currently
+bridged to the caller channel to the specified destination.
diff --git a/menuselect/example_menuselect-tree b/menuselect/example_menuselect-tree
index 6901b709f4..be07fda30f 100644
--- a/menuselect/example_menuselect-tree
+++ b/menuselect/example_menuselect-tree
@@ -10,6 +10,8 @@
 		</member>
 		<member name="app_authenticate" displayname="Authentication Application" remove_on_change="apps/app_authenticate.o apps/app_authenticate.so">
 		</member>
+		<member name="app_blind_transfer" displayname="Blind transfer by caller channel" remove_on_change="apps/app_blind_transfer.o apps/app_blind_transfer.so">
+		</member>
 		<member name="app_cdr" displayname="Tell Asterisk to not maintain a CDR for the current call" remove_on_change="apps/app_cdr.o apps/app_cdr.so">
 		</member>
 		<member name="app_chanisavail" displayname="Check channel availability" remove_on_change="apps/app_chanisavail.o apps/app_chanisavail.so">
diff --git a/menuselect/test/menuselect-tree b/menuselect/test/menuselect-tree
index 40c08b69f1..ac69e90f14 100644
--- a/menuselect/test/menuselect-tree
+++ b/menuselect/test/menuselect-tree
@@ -11,6 +11,8 @@
 </member>
 <member name="app_authenticate" displayname="Authentication Application" remove_on_change="apps/app_authenticate.o apps/app_authenticate.so">
 </member>
+<member name="app_blind_transfer" displayname="Blind transfer by caller channel" remove_on_change="apps/app_blind_transfer.o apps/app_blind_transfer.so">
+</member>
 <member name="app_cdr" displayname="Tell Asterisk to not maintain a CDR for the current call" remove_on_change="apps/app_cdr.o apps/app_cdr.so">
 </member>
 <member name="app_chanisavail" displayname="Check channel availability" remove_on_change="apps/app_chanisavail.o apps/app_chanisavail.so">
-- 
GitLab