Hi,
To double the receive buffer of a socketpair does not help as sending
checks the send buffer size. So double both buffer sizes.
Moreover the default for sending is 2048 and for receiving is 4096.
This makes the existing double buffer algorithm inconsistent. I
think it is better to make the buffers large enough to hold 8 full
length messages. Just make sure that it does not shrink.
I have kept the double size approach. When we are low on buffers
and connot reach the full size, increase it as much as possible.
While there, add consistent error messages.
ok?
bluhm
Index: usr.sbin/syslogd/syslogd.c
===================================================================
RCS file: /data/mirror/openbsd/cvs/src/usr.sbin/syslogd/syslogd.c,v
retrieving revision 1.183
diff -u -p -r1.183 syslogd.c
--- usr.sbin/syslogd/syslogd.c 3 Sep 2015 20:50:48 -0000 1.183
+++ usr.sbin/syslogd/syslogd.c 7 Sep 2015 11:50:58 -0000
@@ -337,7 +337,7 @@ int getmsgbufsize(void);
int socket_bind(const char *, const char *, const char *, int,
int *, int *);
int unix_socket(char *, int, mode_t);
-void double_rbuf(int);
+void double_sockbuf(int, int);
void tailify_replytext(char *, int);
int
@@ -484,13 +484,16 @@ main(int argc, char *argv[])
die(0);
continue;
}
- double_rbuf(fd_unix[i]);
+ double_sockbuf(fd_unix[i], SO_RCVBUF);
}
- if (socketpair(AF_UNIX, SOCK_DGRAM, PF_UNSPEC, pair) == -1)
+ if (socketpair(AF_UNIX, SOCK_DGRAM, PF_UNSPEC, pair) == -1) {
+ logerror("socketpair");
die(0);
+ }
+ double_sockbuf(pair[0], SO_RCVBUF);
+ double_sockbuf(pair[1], SO_SNDBUF);
fd_sendsys = pair[0];
- double_rbuf(fd_sendsys);
fd_ctlsock = fd_ctlconn = -1;
if (path_ctlsock != NULL) {
@@ -792,7 +795,7 @@ socket_bind(const char *proto, const cha
continue;
}
if (!shutread && res->ai_protocol == IPPROTO_UDP)
- double_rbuf(*fdp);
+ double_sockbuf(*fdp, SO_RCVBUF);
}
freeaddrinfo(res0);
@@ -2671,20 +2674,28 @@ unix_socket(char *path, int type, mode_t
optval = MAXLINE + PATH_MAX;
if (setsockopt(fd, SOL_SOCKET, SO_RCVBUF, &optval, sizeof(optval))
== -1)
- logerror("cannot setsockopt unix");
+ logerror("setsockopt unix");
return (fd);
}
void
-double_rbuf(int fd)
+double_sockbuf(int fd, int optname)
{
- socklen_t slen, len;
+ socklen_t len;
+ int i, newsize, oldsize = 0;
- slen = sizeof(len);
- if (getsockopt(fd, SOL_SOCKET, SO_RCVBUF, &len, &slen) == 0) {
- len *= 2;
- setsockopt(fd, SOL_SOCKET, SO_RCVBUF, &len, slen);
+ len = sizeof(oldsize);
+ if (getsockopt(fd, SOL_SOCKET, optname, &oldsize, &len) == 1)
+ logerror("getsockopt bufsize");
+ len = sizeof(newsize);
+ newsize = MAXLINE + 128; /* data + control */
+ /* allow 8 full length messages */
+ for (i = 0; i < 4; i++, newsize *= 2) {
+ if (newsize <= oldsize)
+ continue;
+ if (setsockopt(fd, SOL_SOCKET, optname, &newsize, len) == -1)
+ logerror("setsockopt bufsize");
}
}
