Merged revisions 187362 via svnmerge from

https://origsvn.digium.com/svn/asterisk/branches/1.4

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  r187362 | tilghman | 2009-04-09 11:38:37 -0500 (Thu, 09 Apr 2009) | 3 lines
  
  Permit zero-length text messages in SIP.
  (Related to an issue posted to the -users list, subject "AEL2, BASE64_DECODE and hexadecimal")
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git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@187363 65c4cc65-6c06-0410-ace0-fbb531ad65f3

apps/app_sendtext.c

@@ -81,7 +81,9 @@ static int sendtext_exec(struct ast_channel *chan, void *data)
 		AST_APP_ARG(text);
 	);
 
-	if (ast_strlen_zero(data)) {
+	/* NOT ast_strlen_zero, because some protocols (e.g. SIP) MUST be able to
+	 * send a zero-length message. */
+	if (!data) {
 		ast_log(LOG_WARNING, "SendText requires an argument (text)\n");
 		return -1;
 	} else

channels/chan_sip.c

@@ -4187,7 +4187,9 @@ static int sip_sendtext(struct ast_channel *ast, const char *text)
 		ast_verbose("Sending text %s on %s\n", text, ast->name);
 	if (!p)
 		return -1;
-	if (ast_strlen_zero(text))
+	/* NOT ast_strlen_zero, because a zero-length message is specifically
+	 * allowed by RFC 3428 (See section 10, Examples) */
+	if (!text)
 		return 0;
 	if (debug)
 		ast_verbose("Really sending text %s on %s\n", text, ast->name);