Fix: sessiond app listening: use posix-compliant poll flags

[lttng-tools.git] / src / bin / lttng-sessiond / main.c

diff --git a/src/bin/lttng-sessiond/main.c b/src/bin/lttng-sessiond/main.c
index 6c4b8ec5ce4c94a26b14c33f44839938f8bdd7ac..3cb970c06e21c62c50b42a2e7466ead067a493f9 100644 (file)
--- a/src/bin/lttng-sessiond/main.c
+++ b/src/bin/lttng-sessiond/main.c
@@ -831,8 +831,15 @@ static void *thread_manage_kernel(void *data)
                lttng_poll_reset(&events);
 
                /* Poll infinite value of time */
+       restart:
                ret = lttng_poll_wait(&events, -1);
                if (ret < 0) {
+                       /*
+                        * Restart interrupted system call.
+                        */
+                       if (errno == EINTR) {
+                               goto restart;
+                       }
                        goto error;
                } else if (ret == 0) {
                        /* Should not happen since timeout is infinite */
@@ -922,8 +929,15 @@ static void *thread_manage_consumer(void *data)
        nb_fd = LTTNG_POLL_GETNB(&events);
 
        /* Inifinite blocking call, waiting for transmission */
+restart:
        ret = lttng_poll_wait(&events, -1);
        if (ret < 0) {
+               /*
+                * Restart interrupted system call.
+                */
+               if (errno == EINTR) {
+                       goto restart;
+               }
                goto error;
        }
 
@@ -993,8 +1007,15 @@ static void *thread_manage_consumer(void *data)
        nb_fd = LTTNG_POLL_GETNB(&events);
 
        /* Inifinite blocking call, waiting for transmission */
+restart_poll:
        ret = lttng_poll_wait(&events, -1);
        if (ret < 0) {
+               /*
+                * Restart interrupted system call.
+                */
+               if (errno == EINTR) {
+                       goto restart_poll;
+               }
                goto error;
        }
 
@@ -1077,8 +1098,15 @@ static void *thread_manage_apps(void *data)
                DBG("Apps thread polling on %d fds", nb_fd);
 
                /* Inifinite blocking call, waiting for transmission */
+       restart:
                ret = lttng_poll_wait(&events, -1);
                if (ret < 0) {
+                       /*
+                        * Restart interrupted system call.
+                        */
+                       if (errno == EINTR) {
+                               goto restart;
+                       }
                        goto error;
                }
 
@@ -1138,8 +1166,10 @@ static void *thread_manage_apps(void *data)
                                                /*
                                                 * We just need here to monitor the close of the UST
                                                 * socket and poll set monitor those by default.
+                                                * Listen on POLLIN (even if we never expect any
+                                                * data) to ensure that hangup wakes us.
                                                 */
-                                               ret = lttng_poll_add(&events, ust_cmd.sock, 0);
+                                               ret = lttng_poll_add(&events, ust_cmd.sock, LPOLLIN);
                                                if (ret < 0) {
                                                        goto error;
                                                }
@@ -1296,8 +1326,15 @@ static void *thread_registration_apps(void *data)
                nb_fd = LTTNG_POLL_GETNB(&events);
 
                /* Inifinite blocking call, waiting for transmission */
+       restart:
                ret = lttng_poll_wait(&events, -1);
                if (ret < 0) {
+                       /*
+                        * Restart interrupted system call.
+                        */
+                       if (errno == EINTR) {
+                               goto restart;
+                       }
                        goto error;
                }
 
@@ -3126,10 +3163,25 @@ static int process_client_msg(struct command_ctx *cmd_ctx)
 {
        int ret = LTTCOMM_OK;
        int need_tracing_session = 1;
+       int need_domain;
 
        DBG("Processing client command %d", cmd_ctx->lsm->cmd_type);
 
-       if (opt_no_kernel && cmd_ctx->lsm->domain.type == LTTNG_DOMAIN_KERNEL) {
+       switch (cmd_ctx->lsm->cmd_type) {
+       case LTTNG_CREATE_SESSION:
+       case LTTNG_DESTROY_SESSION:
+       case LTTNG_LIST_SESSIONS:
+       case LTTNG_LIST_DOMAINS:
+       case LTTNG_START_TRACE:
+       case LTTNG_STOP_TRACE:
+               need_domain = 0;
+               break;
+       default:
+               need_domain = 1;
+       }
+
+       if (opt_no_kernel && need_domain
+                       && cmd_ctx->lsm->domain.type == LTTNG_DOMAIN_KERNEL) {
                ret = LTTCOMM_KERN_NA;
                goto error;
        }
@@ -3157,8 +3209,8 @@ static int process_client_msg(struct command_ctx *cmd_ctx)
 
        /* Commands that DO NOT need a session. */
        switch (cmd_ctx->lsm->cmd_type) {
-       case LTTNG_CALIBRATE:
        case LTTNG_CREATE_SESSION:
+       case LTTNG_CALIBRATE:
        case LTTNG_LIST_SESSIONS:
        case LTTNG_LIST_TRACEPOINTS:
                need_tracing_session = 0;
@@ -3183,6 +3235,9 @@ static int process_client_msg(struct command_ctx *cmd_ctx)
                break;
        }
 
+       if (!need_domain) {
+               goto skip_domain;
+       }
        /*
         * Check domain type for specific "pre-action".
         */
@@ -3276,6 +3331,7 @@ static int process_client_msg(struct command_ctx *cmd_ctx)
        default:
                break;
        }
+skip_domain:
 
        /*
         * Check that the UID or GID match that of the tracing session.
@@ -3477,11 +3533,7 @@ static int process_client_msg(struct command_ctx *cmd_ctx)
 
                session_lock_list();
                nr_sessions = lttng_sessions_count(cmd_ctx->creds.uid, cmd_ctx->creds.gid);
-               if (nr_sessions == 0) {
-                       ret = LTTCOMM_NO_SESSION;
-                       session_unlock_list();
-                       goto error;
-               }
+
                ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_session) * nr_sessions);
                if (ret < 0) {
                        session_unlock_list();
@@ -3579,8 +3631,15 @@ static void *thread_manage_clients(void *data)
                nb_fd = LTTNG_POLL_GETNB(&events);
 
                /* Inifinite blocking call, waiting for transmission */
+       restart:
                ret = lttng_poll_wait(&events, -1);
                if (ret < 0) {
+                       /*
+                        * Restart interrupted system call.
+                        */
+                       if (errno == EINTR) {
+                               goto restart;
+                       }
                        goto error;
                }
 
@@ -3917,7 +3976,7 @@ static int check_existing_daemon(void)
  * Set the tracing group gid onto the client socket.
  *
  * Race window between mkdir and chown is OK because we are going from more
- * permissive (root.root) to les permissive (root.tracing).
+ * permissive (root.root) to less permissive (root.tracing).
  */
 static int set_permissions(char *rundir)
 {
@@ -3938,6 +3997,13 @@ static int set_permissions(char *rundir)
                perror("chown");
        }
 
+       /* Ensure tracing group can search the run dir */
+       ret = chmod(rundir, S_IRWXU | S_IXGRP | S_IXOTH);
+       if (ret < 0) {
+               ERR("Unable to set permissions on %s", rundir);
+               perror("chmod");
+       }
+
        /* lttng client socket path */
        ret = chown(client_unix_sock_path, 0, gid);
        if (ret < 0) {
@@ -3997,7 +4063,7 @@ static int create_lttng_rundir(const char *rundir)
 
        DBG3("Creating LTTng run directory: %s", rundir);
 
-       ret = mkdir(rundir, S_IRWXU | S_IRWXG );
+       ret = mkdir(rundir, S_IRWXU);
        if (ret < 0) {
                if (errno != EEXIST) {
                        ERR("Unable to create %s", rundir);
@@ -4039,7 +4105,7 @@ static int set_consumer_sockets(struct consumer_data *consumer_data,
 
        DBG2("Creating consumer directory: %s", path);
 
-       ret = mkdir(path, S_IRWXU | S_IRWXG);
+       ret = mkdir(path, S_IRWXU);
        if (ret < 0) {
                if (errno != EEXIST) {
                        ERR("Failed to create %s", path);