1 files changed, 59 insertions, 0 deletions
diff --git a/src/common.c b/src/common.c
new file mode 100644
index 0000000..558dedf
--- /dev/null
+++ b/src/common.c
@@ -0,0 +1,59 @@
+// 
+// Copyright (C) 2015 Aaron Ball <nullspoon@iohq.net>
+// 
+// Cnetbench 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, either version 3 of the License, or
+// (at your option) any later version.
+// 
+// Cnetbench 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 cnetbench.  If not, see <http://www.gnu.org/licenses/>.
+// 
+#include "common.h"
+
+//
+// Watches an array of pids for their exit, and updates the output array
+// exit_times with each pid's exit timeval struct timestamp (epoch with
+// microseconds).
+//
+// Note that this function does not start the pids, but only watches them. To
+// calculate runtime, external code needs to track when the pids were created.
+//
+// @param pids       Array of pid_t pids to be watched
+// @param count      Number of pids in the pids array
+// @param exit_times Array of timeval structs that will contain exit times for
+//                   all of the pids in the array. Must be at least the size of
+//                   the pids array or unpredictable behavior may result.
+//
+// @return int Overall status of all exited pids (if any fail exit, returns 1)
+//
+int time_pids(pid_t* pids, int count, struct timeval *exit_times) {
+  int i;
+  int waiting = 1;
+
+  while(waiting != 0) {
+    waiting = 0;
+    for(i = 0; i < count; i++) {
+      // Pid with this index has exited, skip it.
+      if(pids[i] == 0)
+        continue;
+
+      // 0 = state change (exit)
+      if(waitpid(pids[i], NULL, WNOHANG) != 0) {
+        // Child has exited
+        pids[i] = 0;
+        // Write the exit time
+        gettimeofday(&exit_times[i], NULL);
+      } else {
+        waiting = 1;
+      }
+    }
+    sleep(1);
+  }
+  return 0;
+}