lib9p: remove Srv.srvfd, make postsrv() and threadpostsrv() return the mountable file descriptor, update documentation

Now that we have these new functions,
we can also make them return an error
instead of calling sysfatal() like
postmountsrv().

Remove the confusing Srv.srvfd, as it
is only temporarily used and return
it from postsrv() instead.

5 files changed, 34 insertions, 32 deletions

diff --git a/sys/src/lib9p/listen.c b/sys/src/lib9p/listen.c
index c7e8dd02c..b093bc287 100644
--- a/sys/src/lib9p/listen.c
+++ b/sys/src/lib9p/listen.c
@@ -18,7 +18,7 @@ listensrv(Srv *os, char *addr)
 	*s = *os;
 
 	s->addr = estrdup9p(addr);
-	s->infd = s->outfd = s->srvfd = -1;
+	s->infd = s->outfd = -1;
 	s->fpool = nil;
 	s->rpool = nil;
 	s->msize = 0;
diff --git a/sys/src/lib9p/mount.c b/sys/src/lib9p/mount.c
index 1adc90bed..1ab41825c 100644
--- a/sys/src/lib9p/mount.c
+++ b/sys/src/lib9p/mount.c
@@ -8,12 +8,15 @@
 void
 postmountsrv(Srv *s, char *name, char *mtpt, int flag)
 {
-	postsrv(s, name);
+	int sfd;
 
+	sfd = postsrv(s, name);
+	if(sfd < 0)
+		sysfatal("postsrv: %r");
 	if(mtpt != nil){
-		if(amount(s->srvfd, mtpt, flag, "") == -1)
+		if(amount(sfd, mtpt, flag, "") == -1)
 			sysfatal("mount %s: %r", mtpt);
-		/* mount closed s->srvfd */
+		/* mount closed sfd */
 	} else
-		close(s->srvfd);
+		close(sfd);
 }
diff --git a/sys/src/lib9p/post.c b/sys/src/lib9p/post.c
index 18ded63ba..b2134968c 100644
--- a/sys/src/lib9p/post.c
+++ b/sys/src/lib9p/post.c
@@ -8,43 +8,41 @@ static void
 postproc(void *v)
 {
 	Srv *s = v;
-	rendezvous(0, 0);
-	close(s->srvfd);
+	close((int)(uintptr)rendezvous(s, 0));
 	srv(s);
 }
 
-void
+int
 postsrv(Srv *s, char *name)
 {
-	char buf[80];
-	int fd[2];
-	int cfd;
+	int fd[2], cfd;
 
 	if(pipe(fd) < 0)
-		sysfatal("pipe: %r");
-	s->infd = s->outfd = fd[1];
-	s->srvfd = fd[0];
-
+		return -1;
 	if(name != nil){
+		char buf[80];
+
 		snprint(buf, sizeof buf, "/srv/%s", name);
-		if((cfd = create(buf, OWRITE|ORCLOSE|OCEXEC, 0600)) < 0)
-			sysfatal("create %s: %r", buf);
-		if(fprint(cfd, "%d", s->srvfd) < 0)
-			sysfatal("write %s: %r", buf);
+		if((cfd = create(buf, OWRITE|ORCLOSE|OCEXEC, 0600)) < 0
+		|| fprint(cfd, "%d", fd[0]) < 0){
+			close(fd[0]);
+			fd[0] = -1;
+			goto Out;
+		}
 	} else
 		cfd = -1;
 
+	/* now we are commited */
+	s->infd = s->outfd = fd[1];
 	if(s->forker == nil)
 		s->forker = srvforker;
 	(*s->forker)(postproc, s, RFNAMEG|RFNOTEG);
 
 	rfork(RFFDG);
-	rendezvous(0, 0);
-
-	close(s->infd);
-	if(s->infd != s->outfd)
-		close(s->outfd);
-
+	rendezvous(s, (void*)(uintptr)fd[0]);
+Out:
 	if(cfd >= 0)
 		close(cfd);
+	close(fd[1]);
+	return fd[0];
 }
diff --git a/sys/src/lib9p/share.c b/sys/src/lib9p/share.c
index ff73e9c3e..afa01c2f2 100644
--- a/sys/src/lib9p/share.c
+++ b/sys/src/lib9p/share.c
@@ -8,7 +8,7 @@ void
 postsharesrv(Srv *s, char *name, char *mtpt, char *desc)
 {
 	char buf[80];
-	int cfd;
+	int cfd, sfd;
 
 	if(mtpt != nil && desc != nil){
 		snprint(buf, sizeof buf, "#σc/%s", mtpt);
@@ -21,12 +21,13 @@ postsharesrv(Srv *s, char *name, char *mtpt, char *desc)
 	} else
 		cfd = -1;
 
-	postsrv(s, name);
-
+	sfd = postsrv(s, name);
+	if(sfd < 0)
+		sysfatal("postsrv: %r");
 	if(cfd >= 0){
-		if(fprint(cfd, "%d\n", s->srvfd) < 0)
+		if(fprint(cfd, "%d\n", sfd) < 0)
 			sysfatal("write %s: %r", buf);
 		close(cfd);
 	}
-	close(s->srvfd);
+	close(sfd);
 }
diff --git a/sys/src/lib9p/threadpostsrv.c b/sys/src/lib9p/threadpostsrv.c
index abdb882e8..b627a8653 100644
--- a/sys/src/lib9p/threadpostsrv.c
+++ b/sys/src/lib9p/threadpostsrv.c
@@ -4,10 +4,10 @@
 #include <thread.h>
 #include <9p.h>
 
-void
+int
 threadpostsrv(Srv *s, char *name)
 {
 	if(s->forker == nil)
 		s->forker = threadsrvforker;
-	postsrv(s, name);
+	return postsrv(s, name);
 }