[gnome-builder] subprocess: add IdeSubprocessSupervisor

[Christian Hergert <chergert src gnome org>]

commit 1189ac3d41448e9991e1016f6b59037ff12b599d
Author: Christian Hergert <chergert redhat com>
Date:   Wed Oct 19 15:46:08 2016 -0700

    subprocess: add IdeSubprocessSupervisor
    
    This will help us monitor processes that we need to keep running.
    Generally we'd prefer to use DBus for stuff like this, but we need
    something simple for external tools such as language-servers.

 libide/Makefile.am                            |    2 +
 libide/subprocess/ide-subprocess-supervisor.c |  268 +++++++++++++++++++++++++
 libide/subprocess/ide-subprocess-supervisor.h |   56 +++++
 3 files changed, 326 insertions(+), 0 deletions(-)
---
diff --git a/libide/Makefile.am b/libide/Makefile.am
index 9aa324e..2d6faa7 100644
--- a/libide/Makefile.am
+++ b/libide/Makefile.am
@@ -126,6 +126,7 @@ libide_1_0_la_public_headers =                            \
        sourceview/ide-source-view.h                      \
        subprocess/ide-subprocess.h                       \
        subprocess/ide-subprocess-launcher.h              \
+       subprocess/ide-subprocess-supervisor.h            \
        symbols/ide-symbol-node.h                         \
        symbols/ide-symbol-resolver.h                     \
        symbols/ide-symbol-tree.h                         \
@@ -292,6 +293,7 @@ libide_1_0_la_public_sources =                            \
        sourceview/ide-source-view.c                      \
        subprocess/ide-subprocess.c                       \
        subprocess/ide-subprocess-launcher.c              \
+       subprocess/ide-subprocess-supervisor.c            \
        symbols/ide-symbol-node.c                         \
        symbols/ide-symbol-resolver.c                     \
        symbols/ide-symbol-tree.c                         \
diff --git a/libide/subprocess/ide-subprocess-supervisor.c b/libide/subprocess/ide-subprocess-supervisor.c
new file mode 100644
index 0000000..176f8b6
--- /dev/null
+++ b/libide/subprocess/ide-subprocess-supervisor.c
@@ -0,0 +1,268 @@
+/* ide-subprocess-supervisor.c
+ *
+ * Copyright (C) 2016 Christian Hergert <chergert redhat com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#define G_LOG_DOMAIN "ide-subproces-supervisor"
+
+#include "ide-subprocess.h"
+#include "ide-subprocess-supervisor.h"
+
+typedef struct
+{
+  IdeSubprocessLauncher *launcher;
+  IdeSubprocess *subprocess;
+  guint supervising : 1;
+} IdeSubprocessSupervisorPrivate;
+
+G_DEFINE_TYPE_WITH_PRIVATE (IdeSubprocessSupervisor, ide_subprocess_supervisor, G_TYPE_OBJECT)
+
+enum {
+  SUPERVISE,
+  UNSUPERVISE,
+  N_SIGNALS
+};
+
+static guint signals [N_SIGNALS];
+
+static void
+ide_subprocess_supervisor_reset (IdeSubprocessSupervisor *self)
+{
+  IdeSubprocessSupervisorPrivate *priv = ide_subprocess_supervisor_get_instance_private (self);
+
+  g_return_if_fail (IDE_IS_SUBPROCESS_SUPERVISOR (self));
+
+  if (priv->subprocess != NULL)
+    {
+      g_autoptr(IdeSubprocess) subprocess = g_steal_pointer (&priv->subprocess);
+
+      if (ide_subprocess_get_if_exited (subprocess))
+        ide_subprocess_force_exit (subprocess);
+    }
+}
+
+static gboolean
+ide_subprocess_supervisor_real_supervise (IdeSubprocessSupervisor *self,
+                                          IdeSubprocessLauncher   *launcher)
+{
+  g_autoptr(IdeSubprocess) subprocess = NULL;
+  g_autoptr(GError) error = NULL;
+
+  g_assert (IDE_IS_SUBPROCESS_SUPERVISOR (self));
+  g_assert (IDE_IS_SUBPROCESS_LAUNCHER (launcher));
+
+  ide_subprocess_supervisor_reset (self);
+
+  subprocess = ide_subprocess_launcher_spawn_sync (launcher, NULL, &error);
+
+  if (subprocess != NULL)
+    ide_subprocess_supervisor_set_subprocess (self, subprocess);
+  else
+    g_warning ("%s", error->message);
+
+  return TRUE;
+}
+
+static gboolean
+ide_subprocess_supervisor_real_unsupervise (IdeSubprocessSupervisor *self,
+                                            IdeSubprocessLauncher   *launcher)
+{
+  g_assert (IDE_IS_SUBPROCESS_SUPERVISOR (self));
+  g_assert (IDE_IS_SUBPROCESS_LAUNCHER (launcher));
+
+  ide_subprocess_supervisor_reset (self);
+
+  return TRUE;
+}
+
+static void
+ide_subprocess_supervisor_finalize (GObject *object)
+{
+  IdeSubprocessSupervisor *self = (IdeSubprocessSupervisor *)object;
+  IdeSubprocessSupervisorPrivate *priv = ide_subprocess_supervisor_get_instance_private (self);
+
+  if (priv->subprocess != NULL && !ide_subprocess_get_if_exited (priv->subprocess))
+    ide_subprocess_force_exit (priv->subprocess);
+
+  g_clear_object (&priv->launcher);
+  g_clear_object (&priv->subprocess);
+
+  G_OBJECT_CLASS (ide_subprocess_supervisor_parent_class)->finalize (object);
+}
+
+static void
+ide_subprocess_supervisor_class_init (IdeSubprocessSupervisorClass *klass)
+{
+  GObjectClass *object_class = G_OBJECT_CLASS (klass);
+
+  object_class->finalize = ide_subprocess_supervisor_finalize;
+
+  signals [SUPERVISE] =
+    g_signal_new_class_handler ("supervise",
+                                G_TYPE_FROM_CLASS (klass),
+                                G_SIGNAL_RUN_LAST,
+                                G_CALLBACK (ide_subprocess_supervisor_real_supervise),
+                                g_signal_accumulator_true_handled, NULL,
+                                NULL,
+                                G_TYPE_BOOLEAN, 1, IDE_TYPE_SUBPROCESS_LAUNCHER);
+
+  signals [UNSUPERVISE] =
+    g_signal_new_class_handler ("unsupervise",
+                                G_TYPE_FROM_CLASS (klass),
+                                G_SIGNAL_RUN_LAST,
+                                G_CALLBACK (ide_subprocess_supervisor_real_unsupervise),
+                                g_signal_accumulator_true_handled, NULL,
+                                NULL,
+                                G_TYPE_BOOLEAN, 1, IDE_TYPE_SUBPROCESS_LAUNCHER);
+}
+
+static void
+ide_subprocess_supervisor_init (IdeSubprocessSupervisor *self)
+{
+}
+
+IdeSubprocessSupervisor *
+ide_subprocess_supervisor_new (void)
+{
+  return g_object_new (IDE_TYPE_SUBPROCESS_SUPERVISOR, NULL);
+}
+
+/**
+ * ide_subprocess_supervisor_get_launcher:
+ *
+ * Returns: (nullable) (transfer none): An #IdeSubprocessLauncher or %NULL.
+ */
+IdeSubprocessLauncher *
+ide_subprocess_supervisor_get_launcher (IdeSubprocessSupervisor *self)
+{
+  IdeSubprocessSupervisorPrivate *priv = ide_subprocess_supervisor_get_instance_private (self);
+
+  g_return_val_if_fail (IDE_IS_SUBPROCESS_SUPERVISOR (self), NULL);
+
+  return priv->launcher;
+}
+
+void
+ide_subprocess_supervisor_set_launcher (IdeSubprocessSupervisor *self,
+                                        IdeSubprocessLauncher   *launcher)
+{
+  IdeSubprocessSupervisorPrivate *priv = ide_subprocess_supervisor_get_instance_private (self);
+
+  g_return_if_fail (IDE_IS_SUBPROCESS_SUPERVISOR (self));
+  g_return_if_fail (!launcher || IDE_IS_SUBPROCESS_LAUNCHER (launcher));
+
+  g_set_object (&priv->launcher, launcher);
+}
+
+void
+ide_subprocess_supervisor_start (IdeSubprocessSupervisor *self)
+{
+  IdeSubprocessSupervisorPrivate *priv = ide_subprocess_supervisor_get_instance_private (self);
+  gboolean ret;
+
+  g_return_if_fail (IDE_IS_SUBPROCESS_SUPERVISOR (self));
+
+  if (priv->launcher == NULL)
+    {
+      g_warning ("Cannot supervise process, no launcher has been set");
+      return;
+    }
+
+  priv->supervising = TRUE;
+
+  g_signal_emit (self, signals [SUPERVISE], 0, priv->launcher, &ret);
+}
+
+void
+ide_subprocess_supervisor_stop (IdeSubprocessSupervisor *self)
+{
+  IdeSubprocessSupervisorPrivate *priv = ide_subprocess_supervisor_get_instance_private (self);
+  gboolean ret;
+
+  g_return_if_fail (IDE_IS_SUBPROCESS_SUPERVISOR (self));
+
+  if (priv->launcher == NULL)
+    {
+      g_warning ("Cannot unsupervise process, no launcher has been set");
+      return;
+    }
+
+  priv->supervising = FALSE;
+
+  g_signal_emit (self, signals [UNSUPERVISE], 0, priv->launcher, &ret);
+}
+
+/**
+ * ide_subprocess_supervisor_get_subprocess:
+ * @self: An #IdeSubprocessSupervisor
+ *
+ * Gets the current #IdeSubprocess that is being supervised. This might be
+ * %NULL if the ide_subprocess_supervisor_start() has not yet been
+ * called or if there was a failure to spawn the process.
+ *
+ * Returns: (nullable) (transfer none): An #IdeSubprocess or %NULL.
+ */
+IdeSubprocess *
+ide_subprocess_supervisor_get_subprocess (IdeSubprocessSupervisor *self)
+{
+  IdeSubprocessSupervisorPrivate *priv = ide_subprocess_supervisor_get_instance_private (self);
+
+  g_return_val_if_fail (IDE_IS_SUBPROCESS_SUPERVISOR (self), NULL);
+
+  return priv->subprocess;
+}
+
+static void
+ide_subprocess_supervisor_wait_cb (GObject      *object,
+                                   GAsyncResult *result,
+                                   gpointer      user_data)
+{
+  IdeSubprocess *subprocess = (IdeSubprocess *)object;
+  g_autoptr(IdeSubprocessSupervisor) self = user_data;
+  IdeSubprocessSupervisorPrivate *priv = ide_subprocess_supervisor_get_instance_private (self);
+  g_autoptr(GError) error = NULL;
+
+  g_return_if_fail (IDE_IS_SUBPROCESS_SUPERVISOR (self));
+  g_return_if_fail (IDE_IS_SUBPROCESS (subprocess));
+
+  if (!ide_subprocess_wait_finish (subprocess, result, &error))
+    g_warning ("%s", error->message);
+
+  if (priv->subprocess == subprocess)
+    {
+      g_clear_object (&priv->subprocess);
+      if (priv->supervising)
+        ide_subprocess_supervisor_start (self);
+    }
+}
+
+void
+ide_subprocess_supervisor_set_subprocess (IdeSubprocessSupervisor *self,
+                                          IdeSubprocess           *subprocess)
+{
+  IdeSubprocessSupervisorPrivate *priv = ide_subprocess_supervisor_get_instance_private (self);
+
+  g_return_if_fail (IDE_IS_SUBPROCESS_SUPERVISOR (self));
+  g_return_if_fail (!subprocess || IDE_IS_SUBPROCESS (subprocess));
+
+  if (g_set_object (&priv->subprocess, subprocess))
+    {
+      ide_subprocess_wait_async (priv->subprocess,
+                                 NULL,
+                                 ide_subprocess_supervisor_wait_cb,
+                                 g_object_ref (self));
+    }
+}
diff --git a/libide/subprocess/ide-subprocess-supervisor.h b/libide/subprocess/ide-subprocess-supervisor.h
new file mode 100644
index 0000000..0839d3e
--- /dev/null
+++ b/libide/subprocess/ide-subprocess-supervisor.h
@@ -0,0 +1,56 @@
+/* ide-subprocess-supervisor.h
+ *
+ * Copyright (C) 2016 Christian Hergert <chergert redhat com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef IDE_SUBPROCESS_SUPERVISOR_H
+#define IDE_SUBPROCESS_SUPERVISOR_H
+
+#include "subprocess/ide-subprocess-launcher.h"
+
+G_BEGIN_DECLS
+
+#define IDE_TYPE_SUBPROCESS_SUPERVISOR (ide_subprocess_supervisor_get_type())
+
+G_DECLARE_DERIVABLE_TYPE (IdeSubprocessSupervisor, ide_subprocess_supervisor, IDE, SUBPROCESS_SUPERVISOR, 
GObject)
+
+struct _IdeSubprocessSupervisorClass
+{
+  GObjectClass parent_class;
+
+  gpointer _reserved1;
+  gpointer _reserved2;
+  gpointer _reserved3;
+  gpointer _reserved4;
+  gpointer _reserved5;
+  gpointer _reserved6;
+  gpointer _reserved7;
+  gpointer _reserved8;
+};
+
+IdeSubprocessSupervisor *ide_subprocess_supervisor_new            (void);
+IdeSubprocessLauncher   *ide_subprocess_supervisor_get_launcher   (IdeSubprocessSupervisor *self);
+void                     ide_subprocess_supervisor_set_launcher   (IdeSubprocessSupervisor *self,
+                                                                   IdeSubprocessLauncher   *launcher);
+void                     ide_subprocess_supervisor_start          (IdeSubprocessSupervisor *self);
+void                     ide_subprocess_supervisor_stop           (IdeSubprocessSupervisor *self);
+IdeSubprocess           *ide_subprocess_supervisor_get_subprocess (IdeSubprocessSupervisor *self);
+void                     ide_subprocess_supervisor_set_subprocess (IdeSubprocessSupervisor *self,
+                                                                   IdeSubprocess           *subprocess);
+
+G_END_DECLS
+
+#endif /* IDE_SUBPROCESS_SUPERVISOR_H */