initial code repo

[stor4nfv.git] / src / ceph / src / common / run_cmd.cc

diff --git a/src/ceph/src/common/run_cmd.cc b/src/ceph/src/common/run_cmd.cc
new file mode 100644 (file)
index 0000000..a84f68a
--- /dev/null
+++ b/src/ceph/src/common/run_cmd.cc
@@ -0,0 +1,80 @@
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+/*
+ * Ceph - scalable distributed file system
+ *
+ * Copyright (C) 2011 New Dream Network
+ *
+ * This is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License version 2.1, as published by the Free Software
+ * Foundation.  See file COPYING.
+ *
+ */
+
+#include "common/errno.h"
+
+#include <sstream>
+#include <stdarg.h>
+#include <sys/wait.h>
+#include <unistd.h>
+#include <vector>
+
+using std::ostringstream;
+
+std::string run_cmd(const char *cmd, ...)
+{
+  std::vector <const char *> arr;
+  va_list ap;
+  va_start(ap, cmd);
+  const char *c = cmd;
+  do {
+    arr.push_back(c);
+    c = va_arg(ap, const char*);
+  } while (c != NULL);
+  va_end(ap);
+  arr.push_back(NULL);
+
+  int fret = fork();
+  if (fret == -1) {
+    int err = errno;
+    ostringstream oss;
+    oss << "run_cmd(" << cmd << "): unable to fork(): " << cpp_strerror(err);
+    return oss.str();
+  }
+  else if (fret == 0) {
+    // execvp doesn't modify its arguments, so the const-cast here is safe.
+    close(STDIN_FILENO);
+    close(STDOUT_FILENO);
+    close(STDERR_FILENO);
+    execvp(cmd, (char * const*)&arr[0]);
+    _exit(127);
+  }
+  int status;
+  while (waitpid(fret, &status, 0) == -1) {
+    int err = errno;
+    if (err == EINTR)
+      continue;
+    ostringstream oss;
+    oss << "run_cmd(" << cmd << "): waitpid error: "
+        << cpp_strerror(err);
+    return oss.str();
+  }
+  if (WIFEXITED(status)) {
+    int wexitstatus = WEXITSTATUS(status);
+    if (wexitstatus != 0) {
+      ostringstream oss;
+      oss << "run_cmd(" << cmd << "): exited with status " << wexitstatus;
+      return oss.str();
+    }
+    return "";
+  }
+  else if (WIFSIGNALED(status)) {
+    ostringstream oss;
+    oss << "run_cmd(" << cmd << "): terminated by signal";
+    return oss.str();
+  }
+  ostringstream oss;
+  oss << "run_cmd(" << cmd << "): terminated by unknown mechanism";
+  return oss.str();
+}