res_pjsip: Forward PJSIP logging to Asterisk logging

This patch uses PJSIP's pj_log_set_log_func() to forward PJSIP's log
messages to Asterisk's logger. This is done in a new module:
res_pjsip_log_forwarder.so.

This patch sets defaultenabled on the existing res_pjsip_logger.so to
no, since logging every SIP packet seems a bit odd to do by default, and
is (hopefully) less necessary with regular PJSIP logging.

It also removes res_rtp_asterisk's disabling of PJSIP logging.

(closes issue ASTERISK-22360)
Reported by: Joshua Colp
Review: https://reviewboard.asterisk.org/r/2830/
........

Merged revisions 399049 from http://svn.asterisk.org/svn/asterisk/branches/12


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@399051 65c4cc65-6c06-0410-ace0-fbb531ad65f3

res/res_pjsip_log_forwarder.c

@@ -0,0 +1,124 @@
+/*
+ * Asterisk -- An open source telephony toolkit.
+ *
+ * Copyright (C) 2013, Digium, Inc.
+ *
+ * David M. Lee, II <dlee@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 Bridge PJSIP logging to Asterisk logging.
+ * \author David M. Lee, II <dlee@digium.com>
+ *
+ * PJSIP logging doesn't exactly match Asterisk logging, but mapping the two is
+ * not too bad. PJSIP log levels are identified by a single int. Limits are
+ * not specified by PJSIP, but their implementation used 1 through 6.
+ *
+ * The mapping is as follows:
+ *  - 0: LOG_ERROR
+ *  - 1: LOG_ERROR
+ *  - 2: LOG_WARNING
+ *  - 3 and above: equivalent to ast_debug(level, ...) for res_pjsip.so
+ */
+
+/*** MODULEINFO
+	<depend>pjproject</depend>
+	<support_level>core</support_level>
+ ***/
+
+#include "asterisk.h"
+
+ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
+
+#include <pjsip.h>
+#include <pj/log.h>
+
+#include "asterisk/logger.h"
+#include "asterisk/module.h"
+
+static pj_log_func *log_cb_orig;
+static unsigned decor_orig;
+
+static void log_cb(int level, const char *data, int len)
+{
+	int ast_level;
+	/* PJSIP doesn't provide much in the way of source info */
+	const char * log_source = "pjsip";
+	int log_line = 0;
+	const char *log_func = "<?>";
+	int mod_level;
+
+	/* Lower number indicates higher importance */
+	switch (level) {
+	case 0: /* level zero indicates fatal error, according to docs */
+	case 1: /* 1 seems to be used for errors */
+		ast_level = __LOG_ERROR;
+		break;
+	case 2: /* 2 seems to be used for warnings and errors */
+		ast_level = __LOG_WARNING;
+		break;
+	default:
+		ast_level = __LOG_DEBUG;
+
+		/* For levels 3 and up, obey the debug level for res_pjsip */
+		mod_level = ast_opt_dbg_module ?
+			ast_debug_get_by_module("res_pjsip") : 0;
+		if (option_debug < level && mod_level < level) {
+			return;
+		}
+		break;
+	}
+
+	/* PJSIP uses indention to indicate function call depth. We'll prepend
+	 * log statements with a tab so they'll have a better shot at lining
+	 * up */
+	ast_log(ast_level, log_source, log_line, log_func, "\t%s\n", data);
+}
+
+static int load_module(void)
+{
+	pj_init();
+
+	decor_orig = pj_log_get_decor();
+	log_cb_orig = pj_log_get_log_func();
+
+	ast_debug(3, "Forwarding PJSIP logger to Asterisk logger\n");
+	/* SENDER prepends the source to the log message. This could be a
+	 * filename, object reference, or simply a string
+	 *
+	 * INDENT is assumed to be on by most log statements in PJSIP itself.
+	 */
+	pj_log_set_decor(PJ_LOG_HAS_SENDER | PJ_LOG_HAS_INDENT);
+	pj_log_set_log_func(log_cb);
+
+	return AST_MODULE_LOAD_SUCCESS;
+}
+
+static int unload_module(void)
+{
+	pj_log_set_log_func(log_cb_orig);
+	pj_log_set_decor(decor_orig);
+
+	pj_shutdown();
+
+	return 0;
+}
+
+/* While we don't really export global symbols, we want to load before other
+ * modules that do */
+AST_MODULE_INFO(ASTERISK_GPL_KEY, AST_MODFLAG_GLOBAL_SYMBOLS | AST_MODFLAG_LOAD_ORDER, "PJSIP Log Forwarder",
+	.load = load_module,
+	.unload = unload_module,
+	.load_pri = AST_MODPRI_CHANNEL_DEPEND - 6,
+	);

res/res_pjsip_logger.c

@@ -19,6 +19,7 @@
 /*** MODULEINFO
 	<depend>pjproject</depend>
 	<depend>res_pjsip</depend>
+	<defaultenabled>no</defaultenabled>
 	<support_level>core</support_level>
  ***/
 

res/res_rtp_asterisk.c

@@ -4537,8 +4537,6 @@ static int load_module(void)
 #ifdef HAVE_PJPROJECT
 	pj_lock_t *lock;
 
-	pj_log_set_level(0);
-
 	if (pj_init() != PJ_SUCCESS) {
 		return AST_MODULE_LOAD_DECLINE;
 	}