From: Ben Pfaff <blp@nicira.com>
Date: Thu, 3 Dec 2009 22:20:33 +0000 (-0800)
Subject: ovsdb-server: Open --listen sockets before detaching.
X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=6dea5eaf5c9fb6e9eaa1610e8a9c44a587bafb25;p=openvswitch

ovsdb-server: Open --listen sockets before detaching.

This prevents a race condition in a command sequence that starts
ovsdb-server and then immediately connects to it with ovsdb-client.
---

diff --git a/ovsdb/jsonrpc-server.c b/ovsdb/jsonrpc-server.c
index 897f9ae5..1c08a10f 100644
--- a/ovsdb/jsonrpc-server.c
+++ b/ovsdb/jsonrpc-server.c
@@ -89,23 +89,15 @@ ovsdb_jsonrpc_server_create(struct ovsdb *db)
     return server;
 }
 
-int
-ovsdb_jsonrpc_server_listen(struct ovsdb_jsonrpc_server *svr, const char *name)
+void
+ovsdb_jsonrpc_server_listen(struct ovsdb_jsonrpc_server *svr,
+                            struct pstream *pstream)
 {
-    struct pstream *pstream;
-    int error;
-
-    error = pstream_open(name, &pstream);
-    if (error) {
-        return error;
-    }
-
     if (svr->n_listeners >= svr->allocated_listeners) {
         svr->listeners = x2nrealloc(svr->listeners, &svr->allocated_listeners,
                                     sizeof *svr->listeners);
     }
     svr->listeners[svr->n_listeners++] = pstream;
-    return 0;
 }
 
 void
diff --git a/ovsdb/jsonrpc-server.h b/ovsdb/jsonrpc-server.h
index 0a80ac61..6ff6fe0c 100644
--- a/ovsdb/jsonrpc-server.h
+++ b/ovsdb/jsonrpc-server.h
@@ -17,11 +17,12 @@
 #define OVSDB_JSONRPC_SERVER_H 1
 
 struct ovsdb;
+struct pstream;
 
 struct ovsdb_jsonrpc_server *ovsdb_jsonrpc_server_create(struct ovsdb *);
 
-int ovsdb_jsonrpc_server_listen(struct ovsdb_jsonrpc_server *,
-                                const char *name);
+void ovsdb_jsonrpc_server_listen(struct ovsdb_jsonrpc_server *,
+                                 struct pstream *);
 void ovsdb_jsonrpc_server_connect(struct ovsdb_jsonrpc_server *,
                                   const char *name);
 
diff --git a/ovsdb/ovsdb-server.c b/ovsdb/ovsdb-server.c
index f6308136..d80161b2 100644
--- a/ovsdb/ovsdb-server.c
+++ b/ovsdb/ovsdb-server.c
@@ -60,6 +60,7 @@ main(int argc, char *argv[])
     struct unixctl_server *unixctl;
     struct ovsdb_jsonrpc_server *jsonrpc;
     struct svec active, passive;
+    struct pstream **listeners;
     struct ovsdb_error *error;
     struct ovsdb *db;
     const char *name;
@@ -78,6 +79,18 @@ main(int argc, char *argv[])
 
     parse_options(argc, argv, &file_name, &active, &passive, &unixctl_path);
 
+    /* Open all the passive sockets before detaching, to avoid race with
+     * processes that start up later. */
+    listeners = xmalloc(passive.n * sizeof *listeners);
+    for (i = 0; i < passive.n; i++) {
+        int error;
+
+        error = pstream_open(passive.names[i], &listeners[i]);
+        if (error) {
+            ovs_fatal(error, "failed to listen on \"%s\"", passive.names[i]);
+        }
+    }
+
     if (get_detach() && is_chdir_enabled()) {
         /* We need to skip chdir("/") in daemonize() and do it later, because
          * we need to open the database and possible set up up Unix domain
@@ -101,11 +114,8 @@ main(int argc, char *argv[])
     SVEC_FOR_EACH (i, name, &active) {
         ovsdb_jsonrpc_server_connect(jsonrpc, name);
     }
-    SVEC_FOR_EACH (i, name, &passive) {
-        retval = ovsdb_jsonrpc_server_listen(jsonrpc, name);
-        if (retval) {
-            ovs_fatal(retval, "failed to listen on %s", name);
-        }
+    for (i = 0; i < passive.n; i++) {
+        ovsdb_jsonrpc_server_listen(jsonrpc, listeners[i]);
     }
     svec_destroy(&active);
     svec_destroy(&passive);