Add a '--list-options' option to each command.

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

diff --git a/src/bin/lttng/lttng.c b/src/bin/lttng/lttng.c
index 2ee93253fe7b50f7ddfc139c58bde769465ec09c..64f3efa446530ed61663c9434eb77251cc923c91 100644 (file)
--- a/src/bin/lttng/lttng.c
+++ b/src/bin/lttng/lttng.c
@@ -22,6 +22,8 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <sys/types.h>
+#include <sys/wait.h>
 #include <unistd.h>
 #include <config.h>
 
@@ -37,6 +39,7 @@ int opt_quiet;
 int opt_verbose;
 static int opt_no_sessiond;
 static char *opt_sessiond_path;
+static pid_t sessiond_pid;
 
 enum {
        OPT_SESSION_PATH,
@@ -168,14 +171,23 @@ static void clean_exit(int code)
  */
 static void sighandler(int sig)
 {
+       int status;
+
        switch (sig) {
                case SIGTERM:
                        DBG("SIGTERM caugth");
                        clean_exit(EXIT_FAILURE);
                        break;
                case SIGCHLD:
-                       /* Notify is done */
                        DBG("SIGCHLD caugth");
+                       waitpid(sessiond_pid, &status, 0);
+                       /* Indicate that the session daemon died */
+                       sessiond_pid = 0;
+                       ERR("Session daemon died (exit status %d)", WEXITSTATUS(status));
+                       break;
+               case SIGUSR1:
+                       /* Notify is done */
+                       DBG("SIGUSR1 caugth");
                        break;
                default:
                        DBG("Unknown signal %d caugth", sig);
@@ -204,7 +216,7 @@ static int set_signal_handler(void)
        sa.sa_handler = sighandler;
        sa.sa_mask = sigset;
        sa.sa_flags = 0;
-       if ((ret = sigaction(SIGCHLD, &sa, NULL)) < 0) {
+       if ((ret = sigaction(SIGUSR1, &sa, NULL)) < 0) {
                perror("sigaction");
                goto end;
        }
@@ -214,6 +226,11 @@ static int set_signal_handler(void)
                goto end;
        }
 
+       if ((ret = sigaction(SIGCHLD, &sa, NULL)) < 0) {
+               perror("sigaction");
+               goto end;
+       }
+
 end:
        return ret;
 }
@@ -246,9 +263,6 @@ static int handle_command(int argc, char **argv)
                        case CMD_ERROR:
                                ERR("Command error");
                                break;
-                       case CMD_NOT_IMPLEMENTED:
-                               ERR("Options not implemented");
-                               break;
                        case CMD_UNDEFINED:
                                ERR("Undefined command");
                                break;
@@ -296,8 +310,12 @@ static int spawn_sessiond(char *pathname)
                kill(getppid(), SIGTERM);       /* unpause parent */
                exit(EXIT_FAILURE);
        } else if (pid > 0) {
+               sessiond_pid = pid;
                /* Wait for lttng-sessiond to start */
                pause();
+               if (!sessiond_pid) {
+                       exit(EXIT_FAILURE);
+               }
                goto end;
        } else {
                perror("fork");
@@ -359,15 +377,19 @@ end:
 }
 
 /*
- * Check for the "help" option in the argv. If found, return 1 else return 0.
+ * Check args for specific options that *must* not trigger a session daemon
+ * execution.
+ *
+ * Return 1 if match else 0.
  */
-static int check_help_command(int argc, char **argv)
+static int check_args_no_sessiond(int argc, char **argv)
 {
        int i;
 
        for (i = 0; i < argc; i++) {
                if ((strncmp(argv[i], "-h", 2) == 0) ||
-                               strncmp(argv[i], "--h", 3) == 0) {
+                               strncmp(argv[i], "--h", 3) == 0 ||
+                               strncmp(argv[i], "--list-options", 14)) {
                        return 1;
                }
        }
@@ -430,7 +452,7 @@ static int parse_args(int argc, char **argv)
        }
 
        /* Spawn session daemon if needed */
-       if (opt_no_sessiond == 0 && check_help_command(argc, argv) == 0 &&
+       if (opt_no_sessiond == 0 && check_args_no_sessiond(argc, argv) == 0 &&
                        (check_sessiond() < 0)) {
                goto error;
        }