From 08ecccc7fedd49072a885b7c809e6d6eb319ffa5 Mon Sep 17 00:00:00 2001
From: Erik Ekman <yarrick@kryo.se>
Date: Sun, 11 Feb 2007 11:51:30 +0000
Subject: [PATCH] #11 only read from tun if any active user is not sending

---
 src/iodined.c | 14 ++++++++++----
 src/user.c    | 20 +++++++++++++++++++-
 src/user.h    |  1 +
 3 files changed, 30 insertions(+), 5 deletions(-)

diff --git a/src/iodined.c b/src/iodined.c
index 0e98072..fb32cba 100644
--- a/src/iodined.c
+++ b/src/iodined.c
@@ -80,10 +80,15 @@ tunnel_tun(int tun_fd, int dns_fd)
 
 	outlen = sizeof(out);
 	compress2((uint8_t*)out, &outlen, (uint8_t*)in, read, 9);
-	memcpy(users[userid].outpacket.data, out, outlen);
-	users[userid].outpacket.len = outlen;
 
-	return outlen;
+	/* if another packet is queued, throw away this one. TODO build queue */
+	if (users[userid].outpacket.len == 0) {
+		memcpy(users[userid].outpacket.data, out, outlen);
+		users[userid].outpacket.len = outlen;
+		return outlen;
+	} else {
+		return 0;
+	}
 }
 
 typedef enum {
@@ -281,7 +286,8 @@ tunnel(int tun_fd, int dns_fd)
 		}
 
 		FD_ZERO(&fds);
-		//if(outpacket.len == 0) TODO fix this
+		/* TODO : use some kind of packet queue */
+		if(!all_users_waiting_to_send())
 			FD_SET(tun_fd, &fds);
 		FD_SET(dns_fd, &fds);
 
diff --git a/src/user.c b/src/user.c
index a85e280..6571f30 100644
--- a/src/user.c
+++ b/src/user.c
@@ -79,12 +79,30 @@ find_user_by_ip(uint32_t ip)
 	return ret;
 }
 
+int
+all_users_waiting_to_send()
+{
+	time_t now;
+	int ret;
+	int i;
+
+	ret = 1;
+	now = time(NULL);
+	for (i = 0; i < USERS; i++) {
+		if (users[i].active && users[i].last_pkt + 60 > now &&
+			users[i].outpacket.len == 0) {
+			ret = 0;
+			break;
+		}
+	}
+	return ret;
+}
+
 int
 find_available_user()
 {
 	int ret = -1;
 	int i;
-
 	for (i = 0; i < USERS; i++) {
 		/* Not used at all or not used in one minute */
 		if (!users[i].active || users[i].last_pkt + 60 < time(NULL)) {
diff --git a/src/user.h b/src/user.h
index f9bbfb1..8e2021d 100644
--- a/src/user.h
+++ b/src/user.h
@@ -37,6 +37,7 @@ extern struct user users[USERS];
 void init_users(in_addr_t);
 int users_waiting_on_reply();
 int find_user_by_ip(uint32_t);
+int all_users_waiting_to_send();
 int find_available_user();
 
 #endif