Fix: Warn if session is running with lttng view

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

diff --git a/src/bin/lttng/commands/view.c b/src/bin/lttng/commands/view.c
index c4724415c31bca500e8054a8dc9411f9d140c7e5..dd3c9a3cc225b06d2ff055fdfb7acdfe0bc141ef 100644 (file)
--- a/src/bin/lttng/commands/view.c
+++ b/src/bin/lttng/commands/view.c
@@ -1,18 +1,18 @@
 /*
  * Copyright (C) 2011 - David Goulet <dgoulet@efficios.com>
  *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License as published by the Free
- * Software Foundation; only version 2 of the License.
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2 only,
+ * as published by the Free Software Foundation.
  *
- * This program is distributed in the hope that it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
- * more details.
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
  *
- * You should have received a copy of the GNU General Public License along with
- * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
- * Place - Suite 330, Boston, MA  02111-1307, USA.
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  */
 
 #define _GNU_SOURCE
@@ -88,6 +88,7 @@ static void usage(FILE *ofp)
        fprintf(ofp, "Where SESSION_NAME is an optional session name. If not specified, lttng will\n");
        fprintf(ofp, "get it from the configuration file (.lttngrc).\n");
        fprintf(ofp, "\n");
+       fprintf(ofp, "Options:\n");
        fprintf(ofp, "  -h, --help               Show this help\n");
        fprintf(ofp, "      --list-options       Simple listing of options\n");
        fprintf(ofp, "  -t, --trace-path PATH    Trace directory path for the viewer\n");
@@ -258,7 +259,11 @@ static int spawn_viewer(const char *trace_path)
 
        ret = execvp(viewer_bin, argv);
        if (ret) {
-               PERROR("exec: %s", viewer_bin);
+               if (errno == ENOENT) {
+                       ERR("%s not found on the system", viewer_bin);
+               } else {
+                       PERROR("exec: %s", viewer_bin);
+               }
                free(argv);
                ret = CMD_FATAL;
                goto error;
@@ -338,6 +343,13 @@ static int view_trace(void)
                trace_path = opt_trace_path;
        }
 
+       if (sessions[i].enabled) {
+               WARN("Session %s is running. Please stop it before reading it.",
+                               session_name);
+               ret = CMD_ERROR;
+               goto free_sessions;
+       }
+
        MSG("Trace directory: %s\n", trace_path);
 
        ret = spawn_viewer(trace_path);
@@ -346,8 +358,6 @@ static int view_trace(void)
                goto free_sessions;
        }
 
-       ret = CMD_SUCCESS;
-
 free_sessions:
        if (sessions) {
                free(sessions);