Cleanup: rename session list count to "next_uuid"

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

diff --git a/src/bin/lttng-sessiond/utils.c b/src/bin/lttng-sessiond/utils.c
index 6c4ef0636927a346485e54685c98623704531c05..d0c8dd16f62571618db8118759d7a8ee4e650a76 100644 (file)
--- a/src/bin/lttng-sessiond/utils.c
+++ b/src/bin/lttng-sessiond/utils.c
@@ -2,22 +2,23 @@
  * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
  *                      Mathieu Desnoyers <mathieu.desnoyers@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
 #include <errno.h>
+#include <fcntl.h>
 #include <limits.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -52,3 +53,77 @@ const char *get_home_dir(void)
 {
        return ((const char *) getenv("HOME"));
 }
+
+/*
+ * Create a pipe in dst.
+ */
+int utils_create_pipe(int *dst)
+{
+       int ret;
+
+       if (dst == NULL) {
+               return -1;
+       }
+
+       ret = pipe(dst);
+       if (ret < 0) {
+               PERROR("create pipe");
+       }
+
+       return ret;
+}
+
+/*
+ * Create pipe and set CLOEXEC flag to both fd.
+ *
+ * Make sure the pipe opened by this function are closed at some point. Use
+ * utils_close_pipe().
+ */
+int utils_create_pipe_cloexec(int *dst)
+{
+       int ret, i;
+
+       if (dst == NULL) {
+               return -1;
+       }
+
+       ret = utils_create_pipe(dst);
+       if (ret < 0) {
+               goto error;
+       }
+
+       for (i = 0; i < 2; i++) {
+               ret = fcntl(dst[i], F_SETFD, FD_CLOEXEC);
+               if (ret < 0) {
+                       PERROR("fcntl pipe cloexec");
+                       goto error;
+               }
+       }
+
+error:
+       return ret;
+}
+
+/*
+ * Close both read and write side of the pipe.
+ */
+void utils_close_pipe(int *src)
+{
+       int i, ret;
+
+       if (src == NULL) {
+               return;
+       }
+
+       for (i = 0; i < 2; i++) {
+               /* Safety check */
+               if (src[i] < 0) {
+                       continue;
+               }
+
+               ret = close(src[i]);
+               if (ret) {
+                       PERROR("close pipe");
+               }
+       }
+}