Standardize quit pipes behavior

[lttng-tools.git] / src / bin / lttng-sessiond / health.cpp

diff --git a/src/bin/lttng-sessiond/health.cpp b/src/bin/lttng-sessiond/health.cpp
index a7f4bdcbb534dc82ae6b6cebaae876043a8f71f5..1ba991447bd5223e17b61cdfe3767692ef9810d5 100644 (file)
--- a/src/bin/lttng-sessiond/health.cpp
+++ b/src/bin/lttng-sessiond/health.cpp
@@ -17,10 +17,12 @@
 #include "utils.hpp"
 #include "thread.hpp"
 
+namespace {
 struct thread_notifiers {
        struct lttng_pipe *quit_pipe;
        sem_t ready;
 };
+} /* namespace */
 
 static
 void mark_thread_as_ready(struct thread_notifiers *notifiers)
@@ -52,14 +54,14 @@ static void cleanup_health_management_thread(void *data)
 static void *thread_manage_health(void *data)
 {
        const bool is_root = (getuid() == 0);
-       int sock = -1, new_sock = -1, ret, i, pollfd, err = -1;
-       uint32_t revents, nb_fd;
+       int sock = -1, new_sock = -1, ret, i, err = -1;
+       uint32_t nb_fd;
        struct lttng_poll_event events;
        struct health_comm_msg msg;
        struct health_comm_reply reply;
        /* Thread-specific quit pipe. */
        struct thread_notifiers *notifiers = (thread_notifiers *) data;
-       const int quit_pipe_read_fd = lttng_pipe_get_readfd(
+       const auto thread_quit_pipe_fd = lttng_pipe_get_readfd(
                        notifiers->quit_pipe);
 
        DBG("[thread] Manage health check started");
@@ -68,7 +70,7 @@ static void *thread_manage_health(void *data)
 
        /*
         * Created with a size of two for:
-        *   - client socket
+        *   - health client socket
         *   - thread quit pipe
         */
        ret = lttng_poll_create(&events, 2, LTTNG_CLOEXEC);
@@ -120,12 +122,12 @@ static void *thread_manage_health(void *data)
                goto error;
        }
 
-       ret = lttng_poll_add(&events, quit_pipe_read_fd, LPOLLIN | LPOLLERR);
+       ret = lttng_poll_add(&events, thread_quit_pipe_fd, LPOLLIN | LPOLLERR);
        if (ret < 0) {
                goto error;
        }
 
-       /* Add the application registration socket */
+       /* Add the health client socket. */
        ret = lttng_poll_add(&events, sock, LPOLLIN | LPOLLPRI);
        if (ret < 0) {
                goto error;
@@ -152,25 +154,26 @@ restart:
 
                for (i = 0; i < nb_fd; i++) {
                        /* Fetch once the poll data */
-                       revents = LTTNG_POLL_GETEV(&events, i);
-                       pollfd = LTTNG_POLL_GETFD(&events, i);
-
-                       /* Event on the registration socket */
-                       if (pollfd == sock) {
-                               if (revents & LPOLLIN) {
-                                       continue;
-                               } else if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
-                                       ERR("Health socket poll error");
-                                       goto error;
-                               } else {
-                                       ERR("Unexpected poll events %u for sock %d", revents, pollfd);
-                                       goto error;
-                               }
-                       } else {
-                               /* Event on the thread's quit pipe. */
+                       const auto revents = LTTNG_POLL_GETEV(&events, i);
+                       const auto pollfd = LTTNG_POLL_GETFD(&events, i);
+
+                       /* Activity on thread quit pipe, exiting. */
+                       if (pollfd == thread_quit_pipe_fd) {
+                               DBG("Activity on thread quit pipe");
                                err = 0;
                                goto exit;
                        }
+
+                       /* Event on the health client socket. */
+                       if (revents & LPOLLIN) {
+                               continue;
+                       } else if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
+                               ERR("Health socket poll error");
+                               goto error;
+                       } else {
+                               ERR("Unexpected poll events %u for sock %d", revents, pollfd);
+                               goto error;
+                       }
                }
 
                new_sock = lttcomm_accept_unix_sock(sock);
@@ -255,7 +258,7 @@ bool launch_health_management_thread(void)
        struct thread_notifiers *notifiers;
        struct lttng_thread *thread;
 
-       notifiers = (thread_notifiers *) zmalloc(sizeof(*notifiers));
+       notifiers = zmalloc<thread_notifiers>();
        if (!notifiers) {
                goto error_alloc;
        }