X-Git-Url: http://git.meshlink.io/?a=blobdiff_plain;f=utcp.c;h=f48460d6f7aa6bf1686fec55cb6841139b62070f;hb=88fac696ff9e360c47e20a8fc8a397004e1ba49e;hp=9f668edd37256e214db12347722c48a79dd8f4cf;hpb=f4c52312544ee99bcce46ebcfc0c8e6ac6356fd5;p=utcp

diff --git a/utcp.c b/utcp.c
index 9f668ed..f48460d 100644
--- a/utcp.c
+++ b/utcp.c
@@ -32,6 +32,27 @@
 
 #include "utcp_priv.h"
 
+#ifndef EBADMSG
+#define EBADMSG         104
+#endif
+
+#ifndef SHUT_RDWR
+#define SHUT_RDWR 2
+#endif
+
+#ifdef poll
+#undef poll
+#endif
+
+#ifndef timersub
+#define timersub(a, b, r) do {\
+	(r)->tv_sec = (a)->tv_sec - (b)->tv_sec;\
+	(r)->tv_usec = (a)->tv_usec - (b)->tv_usec;\
+	if((r)->tv_usec < 0)\
+		(r)->tv_sec--, (r)->tv_usec += 1000000;\
+} while (0)
+#endif
+
 #ifdef UTCP_DEBUG
 #include <stdarg.h>
 
@@ -202,6 +223,7 @@ struct utcp_connection *utcp_connect(struct utcp *utcp, uint16_t dst, utcp_recv_
 		return NULL;
 
 	c->recv = recv;
+	c->priv = priv;
 
 	struct hdr hdr;
 
@@ -254,21 +276,25 @@ static void ack(struct utcp_connection *c, bool sendatleastone) {
 
 	struct {
 		struct hdr hdr;
-		char data[c->utcp->mtu];
-	} pkt;
+		char data[];
+	} *pkt;
 
-	pkt.hdr.src = c->src;
-	pkt.hdr.dst = c->dst;
-	pkt.hdr.ack = c->rcv.nxt;
-	pkt.hdr.wnd = c->snd.wnd;
-	pkt.hdr.ctl = ACK;
-	pkt.hdr.aux = 0;
+	pkt = malloc(sizeof pkt->hdr + c->utcp->mtu);
+	if(!pkt->data)
+		return;
+
+	pkt->hdr.src = c->src;
+	pkt->hdr.dst = c->dst;
+	pkt->hdr.ack = c->rcv.nxt;
+	pkt->hdr.wnd = c->snd.wnd;
+	pkt->hdr.ctl = ACK;
+	pkt->hdr.aux = 0;
 
 	do {
 		uint32_t seglen = left > c->utcp->mtu ? c->utcp->mtu : left;
-		pkt.hdr.seq = c->snd.nxt;
+		pkt->hdr.seq = c->snd.nxt;
 
-		memcpy(pkt.data, data, seglen);
+		memcpy(pkt->data, data, seglen);
 
 		c->snd.nxt += seglen;
 		data += seglen;
@@ -279,16 +305,18 @@ static void ack(struct utcp_connection *c, bool sendatleastone) {
 			case FIN_WAIT_1:
 			case CLOSING:
 				seglen--;
-				pkt.hdr.ctl |= FIN;
+				pkt->hdr.ctl |= FIN;
 				break;
 			default:
 				break;
 			}
 		}
 
-		print_packet(c->utcp, "send", &pkt, sizeof pkt.hdr + seglen);
-		c->utcp->send(c->utcp, &pkt, sizeof pkt.hdr + seglen);
+		print_packet(c->utcp, "send", pkt, sizeof pkt->hdr + seglen);
+		c->utcp->send(c->utcp, pkt, sizeof pkt->hdr + seglen);
 	} while(left);
+
+	free(pkt);
 }
 
 ssize_t utcp_send(struct utcp_connection *c, const void *data, size_t len) {
@@ -596,20 +624,38 @@ ssize_t utcp_recv(struct utcp *utcp, const void *data, size_t len) {
 	// 3. Advance snd.una
 
 	uint32_t advanced = seqdiff(hdr.ack, c->snd.una);
-	c->snd.una = hdr.ack;
+	uint32_t prevrcvnxt = c->rcv.nxt;
 
 	if(advanced) {
-		debug("%p advanced %u\n", utcp, advanced);
+		int32_t data_acked = advanced;
+
+		switch(c->state) {
+			case SYN_SENT:
+			case SYN_RECEIVED:
+				data_acked--;
+				break;
+			// TODO: handle FIN as well.
+			default:
+				break;
+		}
+
+		assert(data_acked >= 0);
+
+		int32_t bufused = seqdiff(c->snd.last, c->snd.una);
+		assert(data_acked <= bufused);
+
 		// Make room in the send buffer.
 		// TODO: try to avoid memmoving too much. Circular buffer?
-		uint32_t left = seqdiff(c->snd.nxt, hdr.ack);
-		if(left)
-			memmove(c->sndbuf, c->sndbuf + advanced, left);
+		uint32_t left = bufused - data_acked;
+		if(data_acked && left)
+			memmove(c->sndbuf, c->sndbuf + data_acked, left);
+
+		c->snd.una = hdr.ack;
+
 		c->dupack = 0;
 		c->snd.cwnd += utcp->mtu;
 		if(c->snd.cwnd > c->maxsndbufsize)
 			c->snd.cwnd = c->maxsndbufsize;
-		debug("%p increasing cwnd to %u\n", utcp, c->snd.cwnd);
 
 		// Check if we have sent a FIN that is now ACKed.
 		switch(c->state) {
@@ -775,14 +821,14 @@ ssize_t utcp_recv(struct utcp *utcp, const void *data, size_t len) {
 		}
 	}
 
-	if(!len && !advanced)
-		return 0;
-
-	if(!len && !(hdr.ctl & SYN) && !(hdr.ctl & FIN))
-		return 0;
+	// Now we send something back if:
+	// - we advanced rcv.nxt (ie, we got some data that needs to be ACKed)
+	//   -> sendatleastone = true
+	// - or we got an ack, so we should maybe send a bit more data
+	//   -> sendatleastone = false
 
 ack:
-	ack(c, true);
+	ack(c, prevrcvnxt != c->rcv.nxt);
 	return 0;
 
 reset:
@@ -913,11 +959,15 @@ static void retransmit(struct utcp_connection *c) {
 
 	struct {
 		struct hdr hdr;
-		char data[c->utcp->mtu];
-	} pkt;
+		char data[];
+	} *pkt;
+
+	pkt = malloc(sizeof pkt->hdr + c->utcp->mtu);
+	if(!pkt)
+		return;
 
-	pkt.hdr.src = c->src;
-	pkt.hdr.dst = c->dst;
+	pkt->hdr.src = c->src;
+	pkt->hdr.dst = c->dst;
 
 	switch(c->state) {
 		case LISTEN:
@@ -925,27 +975,27 @@ static void retransmit(struct utcp_connection *c) {
 			break;
 
 		case SYN_SENT:
-			pkt.hdr.seq = c->snd.iss;
-			pkt.hdr.ack = 0;
-			pkt.hdr.wnd = c->rcv.wnd;
-			pkt.hdr.ctl = SYN;
-			print_packet(c->utcp, "rtrx", &pkt, sizeof pkt.hdr);
-			utcp->send(utcp, &pkt, sizeof pkt.hdr);
+			pkt->hdr.seq = c->snd.iss;
+			pkt->hdr.ack = 0;
+			pkt->hdr.wnd = c->rcv.wnd;
+			pkt->hdr.ctl = SYN;
+			print_packet(c->utcp, "rtrx", pkt, sizeof pkt->hdr);
+			utcp->send(utcp, pkt, sizeof pkt->hdr);
 			break;
 
 		case SYN_RECEIVED:
-			pkt.hdr.seq = c->snd.nxt;
-			pkt.hdr.ack = c->rcv.nxt;
-			pkt.hdr.ctl = SYN | ACK;
-			print_packet(c->utcp, "rtrx", &pkt, sizeof pkt.hdr);
-			utcp->send(utcp, &pkt, sizeof pkt.hdr);
+			pkt->hdr.seq = c->snd.nxt;
+			pkt->hdr.ack = c->rcv.nxt;
+			pkt->hdr.ctl = SYN | ACK;
+			print_packet(c->utcp, "rtrx", pkt, sizeof pkt->hdr);
+			utcp->send(utcp, pkt, sizeof pkt->hdr);
 			break;
 
 		case ESTABLISHED:
 		case FIN_WAIT_1:
-			pkt.hdr.seq = c->snd.una;
-			pkt.hdr.ack = c->rcv.nxt;
-			pkt.hdr.ctl = ACK;
+			pkt->hdr.seq = c->snd.una;
+			pkt->hdr.ack = c->rcv.nxt;
+			pkt->hdr.ctl = ACK;
 			uint32_t len = seqdiff(c->snd.nxt, c->snd.una);
 			if(c->state == FIN_WAIT_1)
 				len--;
@@ -953,17 +1003,19 @@ static void retransmit(struct utcp_connection *c) {
 				len = utcp->mtu;
 			else {
 				if(c->state == FIN_WAIT_1)
-					pkt.hdr.ctl |= FIN;
+					pkt->hdr.ctl |= FIN;
 			}
-			memcpy(pkt.data, c->sndbuf, len);
-			print_packet(c->utcp, "rtrx", &pkt, sizeof pkt.hdr + len);
-			utcp->send(utcp, &pkt, sizeof pkt.hdr + len);
+			memcpy(pkt->data, c->sndbuf, len);
+			print_packet(c->utcp, "rtrx", pkt, sizeof pkt->hdr + len);
+			utcp->send(utcp, pkt, sizeof pkt->hdr + len);
 			break;
 
 		default:
 			// TODO: implement
 			abort();
 	}
+
+	free(pkt);
 }
 
 /* Handle timeouts.
@@ -1003,6 +1055,9 @@ int utcp_timeout(struct utcp *utcp) {
 			retransmit(c);
 		}
 
+		if(c->poll && c->sndbufsize < c->maxsndbufsize / 2)
+			c->poll(c, c->maxsndbufsize - c->sndbufsize);
+
 		if(timerisset(&c->conn_timeout) && timercmp(&c->conn_timeout, &next, <))
 			next = c->conn_timeout;
 
@@ -1078,6 +1133,10 @@ size_t utcp_get_sndbuf(struct utcp_connection *c) {
 	return c->maxsndbufsize;
 }
 
+size_t utcp_get_sndbuf_free(struct utcp_connection *c) {
+	return c->maxsndbufsize - c->sndbufsize;
+}
+
 void utcp_set_sndbuf(struct utcp_connection *c, size_t size) {
 	c->maxsndbufsize = size;
 	if(c->maxsndbufsize != size)
@@ -1103,3 +1162,11 @@ void utcp_set_keepalive(struct utcp_connection *c, bool keepalive) {
 size_t utcp_get_outq(struct utcp_connection *c) {
 	return seqdiff(c->snd.nxt, c->snd.una);
 }
+
+void utcp_set_recv_cb(struct utcp_connection *c, utcp_recv_t recv) {
+	c->recv = recv;
+}
+
+void utcp_set_poll_cb(struct utcp_connection *c, utcp_poll_t poll) {
+	c->poll = poll;
+}