From 547504706ea62956201d40c230d2ab85bd99fbc4 Mon Sep 17 00:00:00 2001

From: "Richard W.M. Jones" <rjones@redhat.com>

Date: Thu, 30 Jun 2016 14:13:24 +0100

Subject: [PATCH] p2v: Send ^C to remote end to cancel the conversion.

We are now able to cancel the conversion instantly by sending ^C to

the remote virt-v2v process.

Also, this reverts:

"p2v: Poll to make Cancel Conversion button more responsive."

(commit 6da4941db7f8a85997d6281b9b4c5165768e6489)

(cherry picked from commit 87131d8681b6e72dac4d8c952f3b3fb7ade02eed)

---

 p2v/conversion.c | 60 +++++++++++++++++++++++++++-----------------------------

 1 file changed, 29 insertions(+), 31 deletions(-)

diff --git a/p2v/conversion.c b/p2v/conversion.c

index f9b8350..484c0e4 100644

--- a/p2v/conversion.c

+++ b/p2v/conversion.c

@@ -25,7 +25,6 @@

 #include <fcntl.h>

 #include <inttypes.h>

 #include <unistd.h>

-#include <poll.h>

 #include <time.h>

 #include <errno.h>

 #include <error.h>

@@ -127,6 +126,7 @@ static pthread_mutex_t running_mutex = PTHREAD_MUTEX_INITIALIZER;

 static int running = 0;

 static pthread_mutex_t cancel_requested_mutex = PTHREAD_MUTEX_INITIALIZER;

 static int cancel_requested = 0;

+static mexp_h *control_h = NULL;

 static int

 is_running (void)

@@ -161,6 +161,21 @@ set_cancel_requested (int r)

 {

   pthread_mutex_lock (&cancel_requested_mutex);

   cancel_requested = r;

+

+  /* Send ^C to the remote so that virt-v2v "knows" the connection has

+   * been cancelled.  mexp_send_interrupt is a single write(2) call.

+   */

+  if (r && control_h)

+    ignore_value (mexp_send_interrupt (control_h));

+

+  pthread_mutex_unlock (&cancel_requested_mutex);

+}

+

+static void

+set_control_h (mexp_h *new_h)

+{

+  pthread_mutex_lock (&cancel_requested_mutex);

+  control_h = new_h;

   pthread_mutex_unlock (&cancel_requested_mutex);

 }

@@ -175,7 +190,6 @@ start_conversion (struct config *config,

   const size_t nr_disks = guestfs_int_count_strings (config->disks);

   time_t now;

   struct tm tm;

-  mexp_h *control_h = NULL;

   struct data_conn data_conns[nr_disks];

   CLEANUP_FREE char *remote_dir = NULL;

   char tmpdir[]           = "/tmp/p2v.XXXXXX";

@@ -189,6 +203,7 @@ start_conversion (struct config *config,

   fprintf (stderr, "\n");

 #endif

+  set_control_h (NULL);

   set_running (1);

   set_cancel_requested (0);

@@ -299,7 +314,7 @@ start_conversion (struct config *config,

   if (notify_ui)

     notify_ui (NOTIFY_STATUS, _("Setting up the control connection ..."));

-  control_h = start_remote_connection (config, remote_dir);

+  set_control_h (start_remote_connection (config, remote_dir));

   if (control_h == NULL) {

     set_conversion_error ("could not open control connection over SSH to the conversion server: %s",

                           get_ssh_error ());

@@ -346,35 +361,13 @@ start_conversion (struct config *config,

   }

   /* Read output from the virt-v2v process and echo it through the

-   * notify function, until virt-v2v closes the connection.  We

-   * actually poll in this loop (albeit it only every 2 seconds) so

-   * that the user won't have to wait too long between pressing the

-   * cancel button and having the conversion cancelled.

+   * notify function, until virt-v2v closes the connection.

    */

   while (!is_cancel_requested ()) {

-    int fd = mexp_get_fd (control_h);

-    struct pollfd fds[1];

-    int rp;

     char buf[257];

     ssize_t r;

-    fds[0].fd = fd;

-    fds[0].events = POLLIN;

-    fds[0].revents = 0;

-    rp = poll (fds, 1, 2000 /* ms */);

-    if (rp == -1) {

-      /* See comment about this in miniexpect.c. */

-      if (errno == EIO)

-        break;

-      set_conversion_error ("poll: %m");

-      goto out;

-    }

-    else if (rp == 0)

-      /* Timeout. */

-      continue;

-    /* ... else rp == 1, ignore revents and just do the read. */

-

-    r = read (fd, buf, sizeof buf - 1);

+    r = read (mexp_get_fd (control_h), buf, sizeof buf - 1);

     if (r == -1) {

       /* See comment about this in miniexpect.c. */

       if (errno == EIO)

@@ -402,12 +395,17 @@ start_conversion (struct config *config,

   ret = 0;

  out:

   if (control_h) {

-    if ((status = mexp_close (control_h)) == -1) {

+    mexp_h *h = control_h;

+    set_control_h (NULL);

+    status = mexp_close (h);

+

+    if (status == -1) {

       set_conversion_error ("mexp_close: %m");

       ret = -1;

-    } else if (ret == 0 &&

-               WIFEXITED (status) &&

-               WEXITSTATUS (status) != 0) {

+    }

+    else if (ret == 0 &&

+             WIFEXITED (status) &&

+             WEXITSTATUS (status) != 0) {

       set_conversion_error ("virt-v2v exited with status %d",

                             WEXITSTATUS (status));

       ret = -1;

-- 

1.8.3.1