X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=dccp_send.c;h=6cfdfbbeddccb42cd46a5d4b8c06aec24a0427ec;hp=0657d11cbe00b55184fa2e612e2f5ffa24acbdae;hb=18f8523446329aaabbcdd14ec2be6fc27802ef4f;hpb=e1a07bd50c0e0bc393abf89a342ce53e10ccf576

diff --git a/dccp_send.c b/dccp_send.c
index 0657d11c..6cfdfbbe 100644
--- a/dccp_send.c
+++ b/dccp_send.c
@@ -32,9 +32,6 @@
 #include "server.cmdline.h"
 #include "acl.h"
 
-/** Do not write more than that many bytes at once. */
-#define DCCP_MAX_BYTES_PER_WRITE 1024
-
 static struct sender_status dccp_sender_status, *dss = &dccp_sender_status;
 
 struct dccp_fec_client {
@@ -86,9 +83,28 @@ static void dccp_shutdown_clients(void)
 		dccp_shutdown_client(sc);
 }
 
+/** * Obtain current MPS according to RFC 4340, sec. 14. */
+static int dccp_init_fec(struct sender_client *sc)
+{
+	int mps, ret;
+	socklen_t ml = sizeof(mps);
+
+	/* If call fails, return some sensible minimum value */
+	ret = getsockopt(sc->fd, SOL_DCCP, DCCP_SOCKOPT_GET_CUR_MPS, &mps, &ml);
+	if (ret < 0) {
+		PARA_NOTICE_LOG("can not determine MPS: %s\n", strerror(errno));
+		mps = generic_max_transport_msg_size(sc->fd) - DCCP_MAX_HEADER;
+	}
+	PARA_INFO_LOG("current MPS = %d bytes\n", mps);
+	assert(mps > 0);
+	if (conf.dccp_max_slice_size_arg > 0)
+		mps = PARA_MIN(mps, conf.dccp_max_slice_size_arg);
+	return mps;
+}
+
 static int dccp_send_fec(struct sender_client *sc, char *buf, size_t len)
 {
-	int ret = write_nonblock(sc->fd, buf, len, DCCP_MAX_BYTES_PER_WRITE);
+	int ret = write_nonblock(sc->fd, buf, len);
 
 	if (ret < 0)
 		dccp_shutdown_client(sc);
@@ -125,10 +141,9 @@ static void dccp_post_select(fd_set *rfds, __a_unused fd_set *wfds)
 	}
 	dfc = para_calloc(sizeof(*dfc));
 	sc->private_data = dfc;
-	dfc->fcp.slices_per_group	= 4;
-	dfc->fcp.data_slices_per_group	= 3;
-	dfc->fcp.max_slice_bytes	= DCCP_MAX_BYTES_PER_WRITE; /* FIXME */
-	dfc->fcp.init_fec		= NULL; /* FIXME */
+	dfc->fcp.data_slices_per_group	= conf.dccp_data_slices_per_group_arg;
+	dfc->fcp.slices_per_group	= conf.dccp_slices_per_group_arg;
+	dfc->fcp.init_fec		= dccp_init_fec;
 	dfc->fcp.send_fec		= dccp_send_fec;
 	dfc->fc = vss_add_fec_client(sc, &dfc->fcp);
 }
@@ -197,7 +212,7 @@ static char *dccp_info(void)
  */
 void dccp_send_init(struct sender *s)
 {
-	int ret;
+	int ret, k, n;
 
 	s->info = dccp_info;
 	s->send = NULL;
@@ -212,6 +227,15 @@ void dccp_send_init(struct sender *s)
 	s->client_cmds[SENDER_ADD] = NULL;
 	s->client_cmds[SENDER_DELETE] = NULL;
 
+	k = conf.dccp_data_slices_per_group_arg;
+	n = conf.dccp_slices_per_group_arg;
+
+	if (k <= 0 || n <= 0 || k >= n) {
+		PARA_WARNING_LOG("invalid FEC parameters, using defaults\n");
+		conf.dccp_data_slices_per_group_arg = 3;
+		conf.dccp_slices_per_group_arg = 4;
+	}
+
 	init_sender_status(dss, conf.dccp_access_arg, conf.dccp_access_given,
 		conf.dccp_port_arg, conf.dccp_max_clients_arg,
 		conf.dccp_default_deny_given);