[Libguestfs] [PATCH v2 2/3] p2v: Remove GDK thread synchronization.
Richard W.M. Jones
rjones at redhat.com
Mon May 30 20:48:59 UTC 2016
Gtk 3 deprecates the GDK thread synchronization locks (functions such
as gdk_threads_enter/gdk_threads_leave), and requires that you issue
all Gtk calls in the main thread. To do this you have to restructure
any code that calls Gtk from other threads so it is wrapped in an idle
task, and so is run from the main thread.
This commit transforms the code in this way.
I found through experimentation that libxcb crashes noisily if you
issue any X11 calls (and hence any significant Gtk calls) when the GDK
thread sychronization initializer has been removed, so if there are
any remaining calls that are missed by this patch we should find out
about them quickly.
---
p2v/gui.c | 289 ++++++++++++++++++++++++++++++++++++++++++-------------------
p2v/main.c | 9 --
2 files changed, 202 insertions(+), 96 deletions(-)
diff --git a/p2v/gui.c b/p2v/gui.c
index f3e448f..633d3a3 100644
--- a/p2v/gui.c
+++ b/p2v/gui.c
@@ -127,7 +127,6 @@ gui_conversion (struct config *config)
show_connection_dialog ();
gtk_main ();
- gdk_threads_leave ();
}
/*----------------------------------------------------------------------*/
@@ -135,6 +134,10 @@ gui_conversion (struct config *config)
static void test_connection_clicked (GtkWidget *w, gpointer data);
static void *test_connection_thread (void *data);
+static gboolean start_spinner (gpointer user_data);
+static gboolean stop_spinner (gpointer user_data);
+static gboolean test_connection_error (gpointer user_data);
+static gboolean test_connection_ok (gpointer user_data);
static void configure_network_button_clicked (GtkWidget *w, gpointer data);
static void about_button_clicked (GtkWidget *w, gpointer data);
static void connection_next_clicked (GtkWidget *w, gpointer data);
@@ -396,43 +399,84 @@ test_connection_thread (void *data)
struct config *copy = data;
int r;
- gdk_threads_enter ();
+ g_idle_add (start_spinner, NULL);
+
+ wait_network_online (copy);
+ r = test_connection (copy);
+ free_config (copy);
+
+ g_idle_add (stop_spinner, NULL);
+
+ if (r == -1)
+ g_idle_add (test_connection_error, NULL);
+ else
+ g_idle_add (test_connection_ok, NULL);
+
+ /* Thread is detached anyway, so no one is waiting for the status. */
+ return NULL;
+}
+
+/**
+ * Idle task called from C<test_connection_thread> (but run on the
+ * main thread) to start the spinner in the connection dialog.
+ */
+static gboolean
+start_spinner (gpointer user_data)
+{
gtk_label_set_text (GTK_LABEL (spinner_message),
_("Testing the connection to the conversion server ..."));
gtk_spinner_start (GTK_SPINNER (spinner));
- gdk_threads_leave ();
+ return FALSE;
+}
- wait_network_online (copy);
- r = test_connection (copy);
- free_config (copy);
-
- gdk_threads_enter ();
+/**
+ * Idle task called from C<test_connection_thread> (but run on the
+ * main thread) to stop the spinner in the connection dialog.
+ */
+static gboolean
+stop_spinner (gpointer user_data)
+{
gtk_spinner_stop (GTK_SPINNER (spinner));
+ return FALSE;
+}
- if (r == -1) {
- /* Error testing the connection. */
- const char *err = get_ssh_error ();
+/**
+ * Idle task called from C<test_connection_thread> (but run on the
+ * main thread) when there is an error. Display the error message and
+ * disable the C<Next> button so the user is forced to correct it.
+ */
+static gboolean
+test_connection_error (gpointer user_data)
+{
+ const char *err = get_ssh_error ();
- gtk_label_set_text (GTK_LABEL (spinner_message), err);
- /* Disable the Next button. */
- gtk_widget_set_sensitive (next_button, FALSE);
- }
- else {
- /* Connection is good. */
- gtk_label_set_text (GTK_LABEL (spinner_message),
- _("Connected to the conversion server.\n"
- "Press the \"Next\" button to configure the conversion process."));
- /* Enable the Next button. */
- gtk_widget_set_sensitive (next_button, TRUE);
- gtk_widget_grab_focus (next_button);
+ gtk_label_set_text (GTK_LABEL (spinner_message), err);
+ /* Disable the Next button. */
+ gtk_widget_set_sensitive (next_button, FALSE);
- /* Update the information in the conversion dialog. */
- set_info_label ();
- }
- gdk_threads_leave ();
+ return FALSE;
+}
- /* Thread is detached anyway, so no one is waiting for the status. */
- return NULL;
+/**
+ * Idle task called from C<test_connection_thread> (but run on the
+ * main thread) when the connection test was successful.
+ */
+static gboolean
+test_connection_ok (gpointer user_data)
+{
+ gtk_label_set_text
+ (GTK_LABEL (spinner_message),
+ _("Connected to the conversion server.\n"
+ "Press the \"Next\" button to configure the conversion process."));
+
+ /* Enable the Next button. */
+ gtk_widget_set_sensitive (next_button, TRUE);
+ gtk_widget_grab_focus (next_button);
+
+ /* Update the information in the conversion dialog. */
+ set_info_label ();
+
+ return FALSE;
}
/**
@@ -1415,11 +1459,12 @@ get_memory_from_conv_dlg (void)
/*----------------------------------------------------------------------*/
/* Running dialog. */
-static void set_log_dir (const char *remote_dir);
-static void set_status (const char *msg);
-static void add_v2v_output (const char *msg);
-static void add_v2v_output_2 (const char *msg, size_t len);
+static gboolean set_log_dir (gpointer remote_dir);
+static gboolean set_status (gpointer msg);
+static gboolean add_v2v_output (gpointer msg);
static void *start_conversion_thread (void *data);
+static gboolean conversion_error (gpointer user_data);
+static gboolean conversion_finished (gpointer user_data);
static void cancel_conversion_clicked (GtkWidget *w, gpointer data);
static void reboot_clicked (GtkWidget *w, gpointer data);
static gboolean close_running_dialog (GtkWidget *w, GdkEvent *event, gpointer data);
@@ -1499,9 +1544,19 @@ show_running_dialog (void)
gtk_widget_set_sensitive (reboot_button, FALSE);
}
-static void
-set_log_dir (const char *remote_dir)
+/**
+ * Display the remote log directory in the running dialog.
+ *
+ * If this isn't called from the main thread, then you must only
+ * call it via an idle task (C<g_idle_add>).
+ *
+ * B<NB:> This frees the remote_dir (C<user_data> pointer) which was
+ * strdup'd in C<notify_ui_callback>.
+ */
+static gboolean
+set_log_dir (gpointer user_data)
{
+ CLEANUP_FREE const char *remote_dir = user_data;
CLEANUP_FREE char *msg;
if (asprintf (&msg,
@@ -1513,45 +1568,70 @@ set_log_dir (const char *remote_dir)
error (EXIT_FAILURE, errno, "asprintf");
gtk_label_set_text (GTK_LABEL (log_label), msg);
+
+ return FALSE;
}
-static void
-set_status (const char *msg)
+/**
+ * Display the conversion status in the running dialog.
+ *
+ * If this isn't called from the main thread, then you must only
+ * call it via an idle task (C<g_idle_add>).
+ *
+ * B<NB:> This frees the message (C<user_data> pointer) which was
+ * strdup'd in C<notify_ui_callback>.
+ */
+static gboolean
+set_status (gpointer user_data)
{
+ CLEANUP_FREE const char *msg = user_data;
+
gtk_label_set_text (GTK_LABEL (status_label), msg);
+
+ return FALSE;
}
+static void add_v2v_output_helper (const char *msg, size_t len);
+
/**
* Append output from the virt-v2v process to the buffer, and scroll
* to ensure it is visible.
+ *
+ * If this isn't called from the main thread, then you must only
+ * call it via an idle task (C<g_idle_add>).
+ *
+ * B<NB:> This frees the message (C<user_data> pointer) which was
+ * strdup'd in C<notify_ui_callback>.
*/
-static void
-add_v2v_output (const char *msg)
+static gboolean
+add_v2v_output (gpointer user_data)
{
+ CLEANUP_FREE const char *msg = user_data;
static size_t linelen = 0;
const char *p0, *p;
- /* Gtk2 (in ~ Fedora 23) has a regression where it takes much
- * longer to display long lines, to the point where the virt-p2v
- * UI would still be slowly display kernel modules while the
- * conversion had finished. For this reason, arbitrarily break
- * long lines.
+ /* Gtk2 (in ~ Fedora 23) has a regression where it takes much longer
+ * to display long lines, to the point where the virt-p2v UI would
+ * still be slowly displaying kernel modules while the conversion
+ * had finished. For this reason, arbitrarily break long lines.
*/
for (p0 = p = msg; *p; ++p) {
linelen++;
if (*p == '\n' || linelen > 1024) {
- add_v2v_output_2 (p0, p-p0+1);
+ add_v2v_output_helper (p0, p-p0+1);
if (*p != '\n')
- add_v2v_output_2 ("\n", 1);
+ add_v2v_output_helper ("\n", 1);
linelen = 0;
p0 = p+1;
}
}
- add_v2v_output_2 (p0, p-p0);
+ add_v2v_output_helper (p0, p-p0);
+
+ return FALSE;
}
static void
-add_v2v_output_2 (const char *msg, size_t len)
+add_v2v_output_helper (const char *msg, size_t len)
{
GtkTextBuffer *buf;
GtkTextIter iter;
@@ -1689,73 +1769,108 @@ start_conversion_thread (void *data)
{
struct config *copy = data;
int r;
- GtkWidget *dlg;
r = start_conversion (copy, notify_ui_callback);
free_config (copy);
- gdk_threads_enter ();
-
- if (r == -1) {
- const char *err = get_conversion_error ();
-
- dlg = gtk_message_dialog_new (GTK_WINDOW (run_dlg),
- GTK_DIALOG_DESTROY_WITH_PARENT,
- GTK_MESSAGE_ERROR,
- GTK_BUTTONS_OK,
- _("Conversion failed: %s"), err);
- gtk_window_set_title (GTK_WINDOW (dlg), _("Conversion failed"));
- gtk_dialog_run (GTK_DIALOG (dlg));
- gtk_widget_destroy (dlg);
- }
- else {
- dlg = gtk_message_dialog_new (GTK_WINDOW (run_dlg),
- GTK_DIALOG_DESTROY_WITH_PARENT,
- GTK_MESSAGE_INFO,
- GTK_BUTTONS_OK,
- _("The conversion was successful."));
- gtk_window_set_title (GTK_WINDOW (dlg), _("Conversion was successful"));
- gtk_dialog_run (GTK_DIALOG (dlg));
- gtk_widget_destroy (dlg);
- }
-
- /* Disable the cancel button. */
- gtk_widget_set_sensitive (cancel_button, FALSE);
-
- /* Enable the reboot button. */
- gtk_widget_set_sensitive (reboot_button, TRUE);
-
- gdk_threads_leave ();
+ if (r == -1)
+ g_idle_add (conversion_error, NULL);
+ else
+ g_idle_add (conversion_finished, NULL);
/* Thread is detached anyway, so no one is waiting for the status. */
return NULL;
}
+/**
+ * Idle task called from C<start_conversion_thread> (but run on the
+ * main thread) when there was an error during the conversion.
+ */
+static gboolean
+conversion_error (gpointer user_data)
+{
+ const char *err = get_conversion_error ();
+ GtkWidget *dlg;
+
+ dlg = gtk_message_dialog_new (GTK_WINDOW (run_dlg),
+ GTK_DIALOG_DESTROY_WITH_PARENT,
+ GTK_MESSAGE_ERROR,
+ GTK_BUTTONS_OK,
+ _("Conversion failed: %s"), err);
+ gtk_window_set_title (GTK_WINDOW (dlg), _("Conversion failed"));
+ gtk_dialog_run (GTK_DIALOG (dlg));
+ gtk_widget_destroy (dlg);
+
+ /* Disable the cancel button. */
+ gtk_widget_set_sensitive (cancel_button, FALSE);
+
+ /* Enable the reboot button. */
+ gtk_widget_set_sensitive (reboot_button, TRUE);
+
+ return FALSE;
+}
+
+/**
+ * Idle task called from C<start_conversion_thread> (but run on the
+ * main thread) when the conversion completed without errors.
+ */
+static gboolean
+conversion_finished (gpointer user_data)
+{
+ GtkWidget *dlg;
+
+ dlg = gtk_message_dialog_new (GTK_WINDOW (run_dlg),
+ GTK_DIALOG_DESTROY_WITH_PARENT,
+ GTK_MESSAGE_INFO,
+ GTK_BUTTONS_OK,
+ _("The conversion was successful."));
+ gtk_window_set_title (GTK_WINDOW (dlg), _("Conversion was successful"));
+ gtk_dialog_run (GTK_DIALOG (dlg));
+ gtk_widget_destroy (dlg);
+
+ /* Disable the cancel button. */
+ gtk_widget_set_sensitive (cancel_button, FALSE);
+
+ /* Enable the reboot button. */
+ gtk_widget_set_sensitive (reboot_button, TRUE);
+
+ return FALSE;
+}
+
+/**
+ * This is called from F<conversion.c>:C<start_conversion>
+ * when there is a status change or a log message.
+ */
static void
notify_ui_callback (int type, const char *data)
{
- gdk_threads_enter ();
+ /* Because we call the functions as idle callbacks which run
+ * in the main thread some time later, we must duplicate the
+ * 'data' parameter (which is always a \0-terminated string).
+ *
+ * This is freed by the idle task function.
+ */
+ char *copy = strdup (data);
switch (type) {
case NOTIFY_LOG_DIR:
- set_log_dir (data);
+ g_idle_add (set_log_dir, (gpointer) copy);
break;
case NOTIFY_REMOTE_MESSAGE:
- add_v2v_output (data);
+ g_idle_add (add_v2v_output, (gpointer) copy);
break;
case NOTIFY_STATUS:
- set_status (data);
+ g_idle_add (set_status, (gpointer) copy);
break;
default:
fprintf (stderr,
"%s: unknown message during conversion: type=%d data=%s\n",
guestfs_int_program_name, type, data);
+ free (copy);
}
-
- gdk_threads_leave ();
}
static gboolean
diff --git a/p2v/main.c b/p2v/main.c
index e1be311..68a846f 100644
--- a/p2v/main.c
+++ b/p2v/main.c
@@ -131,15 +131,6 @@ main (int argc, char *argv[])
*/
udevadm_settle ();
-#if ! GLIB_CHECK_VERSION(2,32,0)
- /* In glib2 < 2.32 you had to call g_thread_init(). In later glib2
- * that is not required and should not be called.
- */
- if (glib_check_version (2, 32, 0) != NULL) /* This checks < 2.32 */
- g_thread_init (NULL);
-#endif
- gdk_threads_init ();
- gdk_threads_enter ();
gui_possible = gtk_init_check (&argc, &argv);
for (;;) {
--
2.7.4
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