libcami: Add a variadic version of ami_action.

Add and expose a version of ami_action that accepts a va_list.

If the user application wants to have its own wrapper around
ami_action, then it would be more efficient to pass us a va_list,
rather than formatting it there only to have us format it again
in ami_action.

Author: InterLinked1

cami.c

@@ -1135,12 +1135,11 @@ static int __attribute__ ((format (printf, 3, 4))) ami_send(struct ami_session *
 	return res;
 }
 
-struct ami_response * __attribute__ ((format (printf, 3, 4))) ami_action(struct ami_session *ami, const char *action, const char *fmt, ...)
+struct ami_response * __attribute__ ((format (printf, 3, 0))) ami_action_va(struct ami_session *ami, const char *action, const char *fmt, va_list ap)
 {
 	struct ami_response *resp = NULL;
 	/* Remember: no trailing \r\n in fmt !*/
 	int res, actionid;
-	va_list ap;
 
 	if (ami->ami_socket < 0) {
 		/* Connection got shutdown */
@@ -1156,10 +1155,8 @@ struct ami_response * __attribute__ ((format (printf, 3, 4))) ami_action(struct
 	/* Nobody sends anything else until we get our response. */
 	pthread_mutex_lock(&ami->ami_read_lock);
 
-	va_start(ap, fmt);
 	/* If we don't have a user-supplied format string, don't add \r\n after ActionID or we'll get 3 sets in a row and cause Asterisk to whine. */
 	res = __ami_send(ami, ap, fmt, fmt && *fmt ? "Action:%s\r\nActionID:%d\r\n" : "Action:%s\r\nActionID:%d", action, ++ami->ami_msg_id);
-	va_end(ap);
 
 	actionid = ami->ami_msg_id; /* This is the ActionID we expect in our response */
 
@@ -1195,6 +1192,17 @@ struct ami_response * __attribute__ ((format (printf, 3, 4))) ami_action(struct
 	return resp;
 }
 
+struct ami_response * __attribute__ ((format (printf, 3, 4))) ami_action(struct ami_session *ami, const char *action, const char *fmt, ...)
+{
+	struct ami_response *resp = NULL;
+	va_list ap;
+
+	va_start(ap, fmt);
+	resp = ami_action_va(ami, action, fmt, ap);
+	va_end(ap);
+	return resp;
+}
+
 int ami_action_login(struct ami_session *ami, const char *username, const char *password)
 {
 	struct ami_response *resp;

include/cami.h

@@ -17,8 +17,8 @@
  */
 
 #define CAMI_VERSION_MAJOR 0
-#define CAMI_VERSION_MINOR 2
-#define CAMI_VERSION_PATCH 1
+#define CAMI_VERSION_MINOR 3
+#define CAMI_VERSION_PATCH 0
 
 /* Max wait time in ms. Don't be tempted to make this too big, as this blocks all AMI traffic. Most of the time, it shouldn't really matter though. */
 #define AMI_MAX_WAIT_TIME 1000
@@ -162,6 +162,9 @@ int ami_action_login(struct ami_session *ami, const char *username, const char *
  */
 int ami_auto_detect_ami_pass(const char *amiusername, char *buf, size_t buflen);
 
+/*! \brief Same as ami_action, but accepts a va_list, for convenience when calling from a variadic function */
+struct ami_response *ami_action_va(struct ami_session *ami, const char *action, const char *fmt, va_list ap);
+
 /*!
  * \brief Request a custom AMI action
  * \param ami