[MEDIUM] unix sockets: cleanup the error reporting path

There were a lot of snprintf() everywhere in the UNIX bind code. Now we
proceed as for tcp and indicate the socket path at the end between square
brackets. The code is smaller and more readable.

diff --git a/src/proto_uxst.c b/src/proto_uxst.c
index a1c83b0232f88d6ec12b64331b2f0539ffb53f6e..dfd66453f5a259eb225d7b3c4452d6483c7d597b 100644 (file)
--- a/src/proto_uxst.c
+++ b/src/proto_uxst.c
@@ -84,47 +84,42 @@ static int create_uxst_socket(const char *path, uid_t uid, gid_t gid, mode_t mod
        char tempname[MAXPATHLEN];
        char backname[MAXPATHLEN];
        struct sockaddr_un addr;
+       const char *msg = NULL;
 
        int ret, sock;
 
        /* 1. create socket names */
        if (!path[0]) {
-               if (errmsg && errlen)
-                       snprintf(errmsg, errlen, "Invalid empty name for a UNIX socket");
+               msg = "Invalid empty name for a UNIX socket";
                goto err_return;
        }
 
        ret = snprintf(tempname, MAXPATHLEN, "%s.%d.tmp", path, pid);
        if (ret < 0 || ret >= MAXPATHLEN) {
-               if (errmsg && errlen)
-                       snprintf(errmsg, errlen, "name too long for UNIX socket (%s)", path);
+               msg = "name too long for UNIX socket";
                goto err_return;
        }
 
        ret = snprintf(backname, MAXPATHLEN, "%s.%d.bak", path, pid);
        if (ret < 0 || ret >= MAXPATHLEN) {
-               if (errmsg && errlen)
-                       snprintf(errmsg, errlen, "name too long for UNIX socket (%s)", path);
+               msg = "name too long for UNIX socket";
                goto err_return;
        }
 
        /* 2. clean existing orphaned entries */
        if (unlink(tempname) < 0 && errno != ENOENT) {
-               if (errmsg && errlen)
-                       snprintf(errmsg, errlen, "error when trying to unlink previous UNIX socket (%s)", path);
+               msg = "error when trying to unlink previous UNIX socket";
                goto err_return;
        }
 
        if (unlink(backname) < 0 && errno != ENOENT) {
-               if (errmsg && errlen)
-                       snprintf(errmsg, errlen, "error when trying to unlink previous UNIX socket (%s)", path);
+               msg = "error when trying to unlink previous UNIX socket";
                goto err_return;
        }
 
        /* 3. backup existing socket */
        if (link(path, backname) < 0 && errno != ENOENT) {
-               if (errmsg && errlen)
-                       snprintf(errmsg, errlen, "error when trying to preserve previous UNIX socket (%s)", path);
+               msg = "error when trying to preserve previous UNIX socket";
                goto err_return;
        }
 
@@ -135,40 +130,34 @@ static int create_uxst_socket(const char *path, uid_t uid, gid_t gid, mode_t mod
 
        sock = socket(PF_UNIX, SOCK_STREAM, 0);
        if (sock < 0) {
-               if (errmsg && errlen)
-                       snprintf(errmsg, errlen, "cannot create socket for UNIX listener (%s)", path);
+               msg = "cannot create UNIX socket";
                goto err_unlink_back;
        }
 
        if (sock >= global.maxsock) {
-               if (errmsg && errlen)
-                       snprintf(errmsg, errlen, "socket(): not enough free sockets for UNIX listener (%s). Raise -n argument", path);
+               msg = "socket(): not enough free sockets, raise -n argument";
                goto err_unlink_temp;
        }
 
        if (fcntl(sock, F_SETFL, O_NONBLOCK) == -1) {
-               if (errmsg && errlen)
-                       snprintf(errmsg, errlen, "cannot make UNIX socket non-blocking");
+               msg = "cannot make UNIX socket non-blocking";
                goto err_unlink_temp;
        }
 
        if (bind(sock, (struct sockaddr *)&addr, sizeof(addr)) < 0) {
                /* note that bind() creates the socket <tempname> on the file system */
-               if (errmsg && errlen)
-                       snprintf(errmsg, errlen, "cannot bind socket for UNIX listener (%s)", path);
+               msg = "cannot bind UNIX socket";
                goto err_unlink_temp;
        }
 
        if (((uid != -1 || gid != -1) && (chown(tempname, uid, gid) == -1)) ||
            (mode != 0 && chmod(tempname, mode) == -1)) {
-               if (errmsg && errlen)
-                       snprintf(errmsg, errlen, "cannot change UNIX socket ownership (%s)", path);
+               msg = "cannot change UNIX socket ownership";
                goto err_unlink_temp;
        }
 
        if (listen(sock, 0) < 0) {
-               if (errmsg && errlen)
-                       snprintf(errmsg, errlen, "cannot listen to socket for UNIX listener (%s)", path);
+               msg = "cannot listen to UNIX socket";
                goto err_unlink_temp;
        }
 
@@ -178,8 +167,7 @@ static int create_uxst_socket(const char *path, uid_t uid, gid_t gid, mode_t mod
         * backname.
         */
        if (rename(tempname, path) < 0) {
-               if (errmsg && errlen)
-                       snprintf(errmsg, errlen, "cannot switch final and temporary sockets for UNIX listener (%s)", path);
+               msg = "cannot switch final and temporary UNIX sockets";
                goto err_rename;
        }
 
@@ -198,6 +186,9 @@ static int create_uxst_socket(const char *path, uid_t uid, gid_t gid, mode_t mod
  err_unlink_back:
        unlink(backname);
  err_return:
+       if (msg && errlen)
+               snprintf(errmsg, errlen, "%s [%s]", msg, path);
+
        return -1;
 }