From de569025d2a282444293d56d4a1209d70f8b7e33 Mon Sep 17 00:00:00 2001
From: Gerrit Renker <grenker@cscs.ch>
Date: Sun, 13 Jun 2010 11:30:47 +0200
Subject: [PATCH] sender: add a hook to resolve target names

This adds a function pointer to interpret and resolve a given URL string in
a target-specific manner, filling in the target's defaults if omitted.

The hook is used for the add/delete commands, currently implemented for UDP.
---
 command.c   | 13 +++++++++++--
 dccp_send.c |  1 +
 http_send.c |  1 +
 send.h      |  9 +++++++++
 udp_send.c  | 23 +++++++++++++++++++++++
 5 files changed, 45 insertions(+), 2 deletions(-)

diff --git a/command.c b/command.c
index 42fa3e75..bcbbc340 100644
--- a/command.c
+++ b/command.c
@@ -191,10 +191,10 @@ static int check_sender_args(int argc, char * const * argv, struct sender_comman
 int com_sender(struct rc4_context *rc4c, int argc, char * const * argv)
 {
 	int i, ret;
+	char *msg = NULL;
 	struct sender_command_data scd;
 
 	if (argc < 2) {
-		char *msg = NULL;
 		for (i = 0; senders[i].name; i++) {
 			char *tmp = make_message("%s%s\n",
 				msg? msg : "", senders[i].name);
@@ -207,7 +207,6 @@ int com_sender(struct rc4_context *rc4c, int argc, char * const * argv)
 	}
 	ret = check_sender_args(argc, argv, &scd);
 	if (ret < 0) {
-		char *msg;
 		if (scd.sender_num < 0)
 			return ret;
 		msg = senders[scd.sender_num].help();
@@ -215,6 +214,16 @@ int com_sender(struct rc4_context *rc4c, int argc, char * const * argv)
 		free(msg);
 		return ret;
 	}
+
+	switch (scd.cmd_num) {
+	case SENDER_ADD:
+	case SENDER_DELETE:
+		assert(senders[scd.sender_num].resolve_target);
+		ret = senders[scd.sender_num].resolve_target(argv[3], &scd);
+		if (ret < 0)
+			return ret;
+	}
+
 	for (i = 0; i < 10; i++) {
 		mutex_lock(mmd_mutex);
 		if (mmd->sender_cmd_data.cmd_num >= 0) {
diff --git a/dccp_send.c b/dccp_send.c
index 6cfdfbbe..41aaf234 100644
--- a/dccp_send.c
+++ b/dccp_send.c
@@ -219,6 +219,7 @@ void dccp_send_init(struct sender *s)
 	s->pre_select = dccp_pre_select;
 	s->post_select = dccp_post_select;
 	s->shutdown_clients = dccp_shutdown_clients;
+	s->resolve_target = NULL;
 	s->help = generic_sender_help;
 	s->client_cmds[SENDER_ON] = dccp_com_on;
 	s->client_cmds[SENDER_OFF] = dccp_com_off;
diff --git a/http_send.c b/http_send.c
index e8b22cf9..e376c464 100644
--- a/http_send.c
+++ b/http_send.c
@@ -251,6 +251,7 @@ void http_send_init(struct sender *s)
 	s->pre_select = http_pre_select;
 	s->post_select = http_post_select;
 	s->shutdown_clients = http_shutdown_clients;
+	s->resolve_target = NULL;
 	s->help = generic_sender_help;
 	s->client_cmds[SENDER_ON] = http_com_on;
 	s->client_cmds[SENDER_OFF] = http_com_off;
diff --git a/send.h b/send.h
index df0cd1cb..5f874521 100644
--- a/send.h
+++ b/send.h
@@ -87,6 +87,15 @@ struct sender {
 	 * pointer means this command is not implemented by this sender.
 	 */
 	int (*client_cmds[NUM_SENDER_CMDS])(struct sender_command_data*);
+	/**
+	 * Resolve target-specific URL string
+	 *
+	 * This method must be defined if the sender supports the add/delete
+	 * subcommands. It interprets a string specifying a target URL in a
+	 * sender-specific fashion (e.g. embedded FEC string). It can also
+	 * fill in sender-specific defaults if necessary.
+	 */
+	int (*resolve_target)(const char *, struct sender_command_data *);
 };
 
 /** Describes one client, connected to a paraslash sender. */
diff --git a/udp_send.c b/udp_send.c
index 24ebf584..adac6a8d 100644
--- a/udp_send.c
+++ b/udp_send.c
@@ -187,6 +187,28 @@ static void udp_shutdown_targets(void)
 		}
 }
 
+static int udp_resolve_target(const char *url, struct sender_command_data *scd)
+{
+	const char *result;
+	int ret, port;
+
+	ret = parse_fec_url(url, scd);
+	if (ret)
+		return ret;
+	port = scd->port > 0 ? scd->port : conf.udp_default_port_arg;
+
+	ret = para_connect_simple(IPPROTO_UDP, scd->host, port);
+	if (ret < 0)
+		return ret;
+
+	result = remote_name(ret);
+	close(ret);
+
+	if (!parse_url(result, scd->host, sizeof(scd->host), &scd->port))
+		return -E_ADDRESS_LOOKUP;
+	return 1;
+}
+
 static int udp_com_on(__a_unused struct sender_command_data *scd)
 {
 	sender_status = SENDER_ON;
@@ -427,6 +449,7 @@ void udp_send_init(struct sender *s)
 	s->pre_select = NULL;
 	s->post_select = NULL;
 	s->shutdown_clients = udp_shutdown_targets;
+	s->resolve_target = udp_resolve_target;
 	s->client_cmds[SENDER_ON] = udp_com_on;
 	s->client_cmds[SENDER_OFF] = udp_com_off;
 	s->client_cmds[SENDER_DENY] = NULL;
-- 
2.39.2