Enable running the daemon under valgrind.

This commit allows you to run the daemon under valgrind.  You have to
enable it at configure time:

  ./configure --enable-valgrind-daemon

This should *not* be done for production builds.

When this feature is enabled, valgrind is added to the appliance and
the daemon is run under valgrind.  Log messages from valgrind are
passed back over a virtio-serial channel into a file called
'valgrind.log.$PID' in the top build directory.

Running 'make check', 'make extra-tests' etc causes many
valgrind.log.* files to be created which must be examined by hand.
(cherry picked from commit d08806adfc5d111b4b6c761540ff508d3f25b66e)

2 files changed, 18 insertions, 0 deletions

diff --git a/src/guestfs.c b/src/guestfs.c
index 31968e4e..3607eaad 100644
--- a/src/guestfs.c
+++ b/src/guestfs.c
@@ -190,9 +190,17 @@ guestfs_close (guestfs_h *g)
   if (g->autosync && g->state == READY)
     guestfs_internal_autosync (g);
 
+  /* If we are valgrinding the daemon, then we *don't* want to kill
+   * the subprocess because we want the final valgrind messages sent
+   * when we close sockets below.  However for normal production use,
+   * killing the subprocess is the right thing to do (in case the
+   * daemon or qemu is not responding).
+   */
+#ifndef VALGRIND_DAEMON
   /* Kill the qemu subprocess. */
   if (g->state != CONFIG)
     guestfs_kill_subprocess (g);
+#endif
 
   /* Run user close callbacks. */
   guestfs___call_callbacks_void (g, GUESTFS_EVENT_CLOSE);
diff --git a/src/launch.c b/src/launch.c
index 1af74b99..4e2fba9d 100644
--- a/src/launch.c
+++ b/src/launch.c
@@ -703,6 +703,16 @@ launch_appliance (guestfs_h *g)
     add_cmdline (g, "-device");
     add_cmdline (g, "virtserialport,chardev=channel0,name=org.libguestfs.channel.0");
 
+#ifdef VALGRIND_DAEMON
+    /* Set up virtio-serial channel for valgrind messages. */
+    add_cmdline (g, "-chardev");
+    snprintf (buf, sizeof buf, "file,path=%s/valgrind.log.%d,id=valgrind",
+              VALGRIND_LOG_PATH, getpid ());
+    add_cmdline (g, buf);
+    add_cmdline (g, "-device");
+    add_cmdline (g, "virtserialport,chardev=valgrind,name=org.libguestfs.valgrind");
+#endif
+
     /* Enable user networking. */
     if (g->enable_network) {
       add_cmdline (g, "-netdev");