Add pidfile cmdline option

[vpp.git] / src / vlib / unix / main.c

diff --git a/src/vlib/unix/main.c b/src/vlib/unix/main.c
index f52316e..c90e133 100644 (file)
--- a/src/vlib/unix/main.c
+++ b/src/vlib/unix/main.c
@@ -317,6 +317,7 @@ unix_config (vlib_main_t * vm, unformat_input_t * input)
   unix_main_t *um = &unix_main;
   clib_error_t *error = 0;
   gid_t gid;
+  int pidfd = -1;
 
   /* Defaults */
   um->cli_pager_buffer_limit = UNIX_CLI_DEFAULT_PAGER_LIMIT;
@@ -415,11 +416,38 @@ unix_config (vlib_main_t * vm, unformat_input_t * input)
          if (setegid (gid) == -1)
            return clib_error_return_unix (0, "setegid");
        }
+      else if (unformat (input, "pidfile %s", &um->pidfile))
+       ;
       else
        return clib_error_return (0, "unknown input `%U'",
                                  format_unformat_error, input);
     }
 
+  if (um->runtime_dir == 0)
+    {
+      uid_t uid = geteuid ();
+      if (uid == 00)
+       um->runtime_dir = format (0, "/run/%s%c",
+                                 vlib_default_runtime_dir, 0);
+      else
+       um->runtime_dir = format (0, "/run/user/%u/%s%c", uid,
+                                 vlib_default_runtime_dir, 0);
+    }
+
+  if (um->pidfile)
+    {
+      if ((error = vlib_unix_validate_runtime_file (um,
+                                                   (char *) um->pidfile,
+                                                   &um->pidfile)))
+       return error;
+
+      if (((pidfd = open ((char *) um->pidfile,
+                         O_CREAT | O_WRONLY | O_TRUNC, 0644)) < 0))
+       {
+         return clib_error_return_unix (0, "open");
+       }
+    }
+
   error = setup_signal_handlers (um);
   if (error)
     return error;
@@ -434,19 +462,21 @@ unix_config (vlib_main_t * vm, unformat_input_t * input)
                                                       0) < 0)
        clib_error_return (0, "daemon () fails");
     }
-  um->unix_config_complete = 1;
 
-  if (um->runtime_dir == 0)
+  if (pidfd >= 0)
     {
-      uid_t uid = geteuid ();
-      if (uid == 00)
-       um->runtime_dir = format (0, "/run/%s%c",
-                                 vlib_default_runtime_dir, 0);
-      else
-       um->runtime_dir = format (0, "/run/user/%u/%s%c", uid,
-                                 vlib_default_runtime_dir, 0);
+      u8 *lv = format (0, "%d", getpid ());
+      if (write (pidfd, (char *) lv, vec_len (lv)) != vec_len (lv))
+       {
+         vec_free (lv);
+         close (pidfd);
+         return clib_error_return_unix (0, "write");
+       }
+      vec_free (lv);
+      close (pidfd);
     }
 
+  um->unix_config_complete = 1;
 
   return 0;
 }
@@ -475,6 +505,9 @@ unix_config (vlib_main_t * vm, unformat_input_t * input)
  * Very useful in situations where folks don't remember or can't be bothered
  * to include CLI commands in bug reports.
  *
+ * @cfgcmd{pidfile, &lt;filename&gt;}
+ * Writes the pid of the main thread in @c filename.
+ *
  * @cfgcmd{full-coredump}
  * Ask the Linux kernel to dump all memory-mapped address regions, instead
  * of just text+data+bss.