ctdb-mutex: Handle pings from lock checking child to parent

The ping timeout is specified by passing an extra argument to the
mutex helper, representing the ping timeout in seconds.

Signed-off-by: Martin Schwenke <martin@meltin.net>
Reviewed-by: Amitay Isaacs <amitay@gmail.com>

diff --git a/ctdb/server/ctdb_mutex_fcntl_helper.c b/ctdb/server/ctdb_mutex_fcntl_helper.c
index 79edd8388f66b179a037af0207525ac71668665b..cdc1450cd2b14fd4356e648846387898acacac5c 100644 (file)
--- a/ctdb/server/ctdb_mutex_fcntl_helper.c
+++ b/ctdb/server/ctdb_mutex_fcntl_helper.c
@@ -272,17 +272,19 @@ static struct tevent_req *lock_test_child_send(TALLOC_CTX *mem_ctx,
                                               const char *lock_file,
                                               int fd,
                                               ino_t inode,
-                                              unsigned long recheck_interval)
+                                              unsigned long recheck_interval,
+                                              bool send_pings)
 {
        struct tevent_req *req, *subreq;
        struct lock_test_child_state *state;
+       unsigned int interval = send_pings ? 1 : 0;
 
        req = tevent_req_create(mem_ctx, &state, struct lock_test_child_state);
        if (req == NULL) {
                return NULL;
        }
 
-       subreq = tmon_ping_send(state, ev, fd, TMON_FD_BOTH, 0, 0);
+       subreq = tmon_ping_send(state, ev, fd, TMON_FD_BOTH, 0, interval);
        if (tevent_req_nomem(subreq, req)) {
                return tevent_req_post(req, ev);
        }
@@ -351,7 +353,8 @@ static bool lock_test_child_recv(struct tevent_req *req, int *perr)
 static void lock_test_child(const char *lock_file,
                            int lock_fd,
                            int pipe_fd,
-                           unsigned long recheck_interval)
+                           unsigned long recheck_interval,
+                           bool send_pings)
 {
        struct tevent_context *ev;
        struct tevent_req *req;
@@ -384,7 +387,8 @@ static void lock_test_child(const char *lock_file,
                                   lock_file,
                                   pipe_fd,
                                   inode,
-                                  recheck_interval);
+                                  recheck_interval,
+                                  send_pings);
        if (req == NULL) {
                fprintf(stderr,
                        "%s: lock_test_child_send() failed\n",
@@ -418,7 +422,8 @@ static struct tevent_req *lock_test_send(TALLOC_CTX *mem_ctx,
                                         struct tevent_context *ev,
                                         const char *lock_file,
                                         int *fdp,
-                                        unsigned long recheck_interval)
+                                        unsigned long recheck_interval,
+                                        unsigned long ping_timeout)
 {
        struct tevent_req *req, *subreq;
        struct lock_test_state *state;
@@ -456,7 +461,11 @@ static struct tevent_req *lock_test_send(TALLOC_CTX *mem_ctx,
                close(sv[0]);
                TALLOC_FREE(ev);
 
-               lock_test_child(lock_file, *fdp, sv[1], recheck_interval);
+               lock_test_child(lock_file,
+                               *fdp,
+                               sv[1],
+                               recheck_interval,
+                               ping_timeout != 0);
                /* Above does not return */
        }
 
@@ -467,7 +476,7 @@ static struct tevent_req *lock_test_send(TALLOC_CTX *mem_ctx,
        state->pipe_fd = sv[0];
        state->child_pid = pid;
 
-       subreq = tmon_ping_send(state, ev, sv[0], TMON_FD_BOTH, 0, 0);
+       subreq = tmon_ping_send(state, ev, sv[0], TMON_FD_BOTH, ping_timeout, 0);
        if (tevent_req_nomem(subreq, req)) {
                close(sv[0]);
                return tevent_req_post(req, ev);
@@ -547,7 +556,8 @@ static struct tevent_req *wait_for_exit_send(TALLOC_CTX *mem_ctx,
                                             pid_t ppid,
                                             const char *lock_file,
                                             int *fdp,
-                                            unsigned long recheck_interval)
+                                            unsigned long recheck_interval,
+                                            unsigned long ping_timeout)
 {
        struct tevent_req *req, *subreq;
        struct wait_for_exit_state *state;
@@ -568,7 +578,8 @@ static struct tevent_req *wait_for_exit_send(TALLOC_CTX *mem_ctx,
                                        ev,
                                        lock_file,
                                        fdp,
-                                       recheck_interval);
+                                       recheck_interval,
+                                       ping_timeout);
                if (tevent_req_nomem(subreq, req)) {
                        return tevent_req_post(req, ev);
                }
@@ -633,7 +644,9 @@ static bool wait_for_exit_recv(struct tevent_req *req, int *perr)
 
 static void usage(void)
 {
-       fprintf(stderr, "Usage: %s <file> [recheck_interval]\n", progname);
+       fprintf(stderr,
+               "Usage: %s <file> [recheck_interval [ping_timeout]]\n",
+               progname);
 }
 
 int main(int argc, char *argv[])
@@ -643,6 +656,7 @@ int main(int argc, char *argv[])
        int ppid;
        const char *file = NULL;
        unsigned long recheck_interval;
+       unsigned long ping_timeout;
        int ret;
        int fd = -1;
        struct tevent_req *req;
@@ -651,7 +665,7 @@ int main(int argc, char *argv[])
        strlcpy(progpath, argv[0], sizeof(progpath));
        progname = basename(progpath);
 
-       if (argc < 2 || argc > 3) {
+       if (argc < 2 || argc > 4) {
                usage();
                exit(1);
        }
@@ -667,7 +681,8 @@ int main(int argc, char *argv[])
        file = argv[1];
 
        recheck_interval = 5;
-       if (argc == 3) {
+       ping_timeout = 0;
+       if (argc >= 3) {
                recheck_interval = smb_strtoul(argv[2],
                                               NULL,
                                               10,
@@ -678,6 +693,17 @@ int main(int argc, char *argv[])
                        exit(1);
                }
        }
+       if (argc >= 4) {
+               ping_timeout = smb_strtoul(argv[3],
+                                          NULL,
+                                          10,
+                                          &ret,
+                                          SMB_STR_STANDARD);
+               if (ret != 0) {
+                       usage();
+                       exit(1);
+               }
+       }
 
        result = fcntl_lock(file, &fd);
        sys_write(STDOUT_FILENO, &result, 1);
@@ -686,7 +712,13 @@ int main(int argc, char *argv[])
                return 0;
        }
 
-       req = wait_for_exit_send(ev, ev, ppid, file, &fd, recheck_interval);
+       req = wait_for_exit_send(ev,
+                                ev,
+                                ppid,
+                                file,
+                                &fd,
+                                recheck_interval,
+                                ping_timeout);
        if (req == NULL) {
                fprintf(stderr,
                        "%s: wait_for_exit_send() failed\n",