X-Git-Url: http://git.efficios.com/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fbin%2Flttng%2Fcommands%2Fcreate.c;h=a7d327fbcada361477b71f44d025595adba67056;hp=b8d9f3b5655c56975bfa1716a08065b86ca1ca14;hb=d1edd8a82868dafce6d61600c87ac916d7f73702;hpb=d7ba13889c8692b14f99238ddf2721ed78df89d2

diff --git a/src/bin/lttng/commands/create.c b/src/bin/lttng/commands/create.c
index b8d9f3b56..a7d327fbc 100644
--- a/src/bin/lttng/commands/create.c
+++ b/src/bin/lttng/commands/create.c
@@ -27,6 +27,8 @@
 #include <sys/types.h>
 #include <time.h>
 #include <unistd.h>
+#include <signal.h>
+#include <sys/wait.h>
 
 #include <common/mi-lttng.h>
 
@@ -79,7 +81,7 @@ static struct poptOption long_options[] = {
  * why this declaration exists and used ONLY in for this command.
  */
 extern int _lttng_create_session_ext(const char *name, const char *url,
-		const char *datetime, int live_timer);
+		const char *datetime);
 
 /*
  * usage
@@ -458,7 +460,7 @@ static int create_session(void)
 		}
 		ret = lttng_create_session_live(session_name, url, opt_live_timer);
 	} else {
-		ret = _lttng_create_session_ext(session_name, url, datetime, -1);
+		ret = _lttng_create_session_ext(session_name, url, datetime);
 	}
 	if (ret < 0) {
 		/* Don't set ret so lttng can interpret the sessiond error. */
@@ -550,6 +552,129 @@ error:
 	return ret;
 }
 
+/*
+ *  spawn_sessiond
+ *
+ *  Spawn a session daemon by forking and execv.
+ */
+static int spawn_sessiond(char *pathname)
+{
+	int ret = 0;
+	pid_t pid;
+
+	MSG("Spawning a session daemon");
+	pid = fork();
+	if (pid == 0) {
+		/*
+		 * Spawn session daemon in daemon mode.
+		 */
+		execlp(pathname, "lttng-sessiond",
+				"--daemonize", NULL);
+		/* execlp only returns if error happened */
+		if (errno == ENOENT) {
+			ERR("No session daemon found. Use --sessiond-path.");
+		} else {
+			PERROR("execlp");
+		}
+		kill(getppid(), SIGTERM);	/* wake parent */
+		exit(EXIT_FAILURE);
+	} else if (pid > 0) {
+		int status;
+
+		/*
+		 * In daemon mode (--daemonize), sessiond only exits when
+		 * it's ready to accept commands.
+		 */
+		for (;;) {
+			waitpid(pid, &status, 0);
+
+			if (WIFSIGNALED(status)) {
+				ERR("Session daemon was killed by signal %d",
+						WTERMSIG(status));
+				ret = -1;
+			        goto end;
+			} else if (WIFEXITED(status)) {
+				DBG("Session daemon terminated normally (exit status: %d)",
+						WEXITSTATUS(status));
+
+				if (WEXITSTATUS(status) != 0) {
+					ERR("Session daemon terminated with an error (exit status: %d)",
+							WEXITSTATUS(status));
+					ret = -1;
+				        goto end;
+				}
+				break;
+			}
+		}
+
+		goto end;
+	} else {
+		PERROR("fork");
+		ret = -1;
+		goto end;
+	}
+
+end:
+	return ret;
+}
+
+/*
+ *  launch_sessiond
+ *
+ *  Check if the session daemon is available using
+ *  the liblttngctl API for the check. If not, try to
+ *  spawn a daemon.
+ */
+static int launch_sessiond(void)
+{
+	int ret;
+	char *pathname = NULL;
+
+	ret = lttng_session_daemon_alive();
+	if (ret) {
+		/* Sessiond is alive, not an error */
+		ret = 0;
+		goto end;
+	}
+
+	/* Try command line option path */
+	pathname = opt_sessiond_path;
+
+	/* Try LTTNG_SESSIOND_PATH env variable */
+	if (pathname == NULL) {
+		pathname = getenv(DEFAULT_SESSIOND_PATH_ENV);
+	}
+
+	/* Try with configured path */
+	if (pathname == NULL) {
+		if (CONFIG_SESSIOND_BIN[0] != '\0') {
+			pathname = CONFIG_SESSIOND_BIN;
+		}
+	}
+
+	/* Try the default path */
+	if (pathname == NULL) {
+		pathname = INSTALL_BIN_PATH "/lttng-sessiond";
+	}
+
+	DBG("Session daemon binary path: %s", pathname);
+
+	/* Check existence and permissions */
+	ret = access(pathname, F_OK | X_OK);
+	if (ret < 0) {
+		ERR("No such file or access denied: %s", pathname);
+		goto end;
+	}
+
+	ret = spawn_sessiond(pathname);
+end:
+	if (ret) {
+		ERR("Problem occurred while launching session daemon (%s)",
+				pathname);
+	}
+	return ret;
+}
+
 /*
  *  The 'create <options>' first level command
  *
@@ -597,6 +722,11 @@ int cmd_create(int argc, const char **argv)
 				ret = CMD_ERROR;
 				goto end;
 			}
+			if (v == 0) {
+				ERR("Live timer interval must be greater than zero");
+				ret = CMD_ERROR;
+				goto end;
+			}
 			opt_live_timer = (uint32_t) v;
 			DBG("Session live timer interval set to %d", opt_live_timer);
 			break;
@@ -614,6 +744,15 @@ int cmd_create(int argc, const char **argv)
 		goto end;
 	}
 
+	/* Spawn a session daemon if needed */
+	if (!opt_no_sessiond) {
+		ret = launch_sessiond();
+		if (ret) {
+			ret = CMD_ERROR;
+			goto end;
+		}
+	}
+
 	/* MI initialization */
 	if (lttng_opt_mi) {
 		writer = mi_lttng_writer_create(fileno(stdout), lttng_opt_mi);