Cleanup poll handling events

Make the accept in the thread client only if we have a POLLIN request.

Signed-off-by: David Goulet <david.goulet@polymtl.ca>

diff --git a/ltt-sessiond/main.c b/ltt-sessiond/main.c
index 91f79b3c5cdfc363de10dd080550cc251eb6a330..77497d570b68e3e10aaf2a2386321ac66bd55d8c 100644 (file)
--- a/ltt-sessiond/main.c
+++ b/ltt-sessiond/main.c
@@ -2643,8 +2643,8 @@ static void *thread_manage_clients(void *data)
        pollfd[1].fd = client_sock;
        pollfd[1].events = POLLIN;
 
-       /* Notify parent pid that we are ready
-        * to accept command for client side.
+       /*
+        * Notify parent pid that we are ready to accept command for client side.
         */
        if (opt_sig_parent) {
                kill(ppid, SIGCHLD);
@@ -2663,63 +2663,69 @@ static void *thread_manage_clients(void *data)
                /* Thread quit pipe has been closed. Killing thread. */
                if (pollfd[0].revents == POLLNVAL) {
                        goto error;
-               } else if (pollfd[1].revents == POLLERR) {
-                       ERR("Client socket poll error");
-                       goto error;
                }
 
-               sock = lttcomm_accept_unix_sock(client_sock);
-               if (sock < 0) {
+               switch (pollfd[1].revents) {
+               case POLLNVAL:
+               case POLLHUP:
+               case POLLERR:
+                       ERR("Client socket poll error");
                        goto error;
-               }
+               case POLLIN:
+                       sock = lttcomm_accept_unix_sock(client_sock);
+                       if (sock < 0) {
+                               goto error;
+                       }
 
-               /* Allocate context command to process the client request */
-               cmd_ctx = malloc(sizeof(struct command_ctx));
+                       /* Allocate context command to process the client request */
+                       cmd_ctx = malloc(sizeof(struct command_ctx));
 
-               /* Allocate data buffer for reception */
-               cmd_ctx->lsm = malloc(sizeof(struct lttcomm_session_msg));
-               cmd_ctx->llm = NULL;
-               cmd_ctx->session = NULL;
+                       /* Allocate data buffer for reception */
+                       cmd_ctx->lsm = malloc(sizeof(struct lttcomm_session_msg));
+                       cmd_ctx->llm = NULL;
+                       cmd_ctx->session = NULL;
 
-               /*
-                * Data is received from the lttng client. The struct
-                * lttcomm_session_msg (lsm) contains the command and data request of
-                * the client.
-                */
-               DBG("Receiving data from client ...");
-               ret = lttcomm_recv_unix_sock(sock, cmd_ctx->lsm, sizeof(struct lttcomm_session_msg));
-               if (ret <= 0) {
-                       continue;
-               }
+                       /*
+                        * Data is received from the lttng client. The struct
+                        * lttcomm_session_msg (lsm) contains the command and data request of
+                        * the client.
+                        */
+                       DBG("Receiving data from client ...");
+                       ret = lttcomm_recv_unix_sock(sock, cmd_ctx->lsm, sizeof(struct lttcomm_session_msg));
+                       if (ret <= 0) {
+                               continue;
+                       }
 
-               // TODO: Validate cmd_ctx including sanity check for security purpose.
+                       // TODO: Validate cmd_ctx including sanity check for security purpose.
 
-               /*
-                * This function dispatch the work to the kernel or userspace tracer
-                * libs and fill the lttcomm_lttng_msg data structure of all the needed
-                * informations for the client. The command context struct contains
-                * everything this function may needs.
-                */
-               ret = process_client_msg(cmd_ctx);
-               if (ret < 0) {
-                       /* TODO: Inform client somehow of the fatal error. At this point,
-                        * ret < 0 means that a malloc failed (ENOMEM). */
-                       /* Error detected but still accept command */
-                       clean_command_ctx(&cmd_ctx);
-                       continue;
-               }
+                       /*
+                        * This function dispatch the work to the kernel or userspace tracer
+                        * libs and fill the lttcomm_lttng_msg data structure of all the needed
+                        * informations for the client. The command context struct contains
+                        * everything this function may needs.
+                        */
+                       ret = process_client_msg(cmd_ctx);
+                       if (ret < 0) {
+                               /* TODO: Inform client somehow of the fatal error. At this point,
+                                * ret < 0 means that a malloc failed (ENOMEM). */
+                               /* Error detected but still accept command */
+                               clean_command_ctx(&cmd_ctx);
+                               continue;
+                       }
 
-               DBG("Sending response (size: %d, retcode: %d)",
-                               cmd_ctx->lttng_msg_size, cmd_ctx->llm->ret_code);
-               ret = send_unix_sock(sock, cmd_ctx->llm, cmd_ctx->lttng_msg_size);
-               if (ret < 0) {
-                       ERR("Failed to send data back to client");
-               }
+                       DBG("Sending response (size: %d, retcode: %d)",
+                                       cmd_ctx->lttng_msg_size, cmd_ctx->llm->ret_code);
+                       ret = send_unix_sock(sock, cmd_ctx->llm, cmd_ctx->lttng_msg_size);
+                       if (ret < 0) {
+                               ERR("Failed to send data back to client");
+                       }
 
-               clean_command_ctx(&cmd_ctx);
+                       clean_command_ctx(&cmd_ctx);
 
-               /* End of transmission */
-               close(sock);
+                       /* End of transmission */
+                       close(sock);
+                       break;
+               }
        }
 
 error: