[glib] GUnixVolume: port to GSubprocess

[Ryan Lortie <desrt src gnome org>]

commit 62fa9c578f4ee3f2ca5127961a4609596a4bdaee
Author: Ryan Lortie <desrt desrt ca>
Date:   Sun Mar 2 21:24:14 2014 -0500

    GUnixVolume: port to GSubprocess
    
    Do the same as we just did for GUnixMount, for GUnixVolume too.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=724916

 gio/gunixvolume.c |  174 +++++++++++-----------------------------------------
 1 files changed, 37 insertions(+), 137 deletions(-)
---
diff --git a/gio/gunixvolume.c b/gio/gunixvolume.c
index 079b902..0ebcda7 100644
--- a/gio/gunixvolume.c
+++ b/gio/gunixvolume.c
@@ -265,160 +265,60 @@ _g_unix_volume_has_mount_path (GUnixVolume *volume,
   return strcmp (volume->mount_path, mount_path) == 0;
 }
 
-
-typedef struct {
-  GUnixVolume *unix_volume;
-  int error_fd;
-  GIOChannel *error_channel;
-  GSource *error_channel_source;
-  GString *error_string;
-} EjectMountOp;
-
-static void
-eject_mount_op_free (EjectMountOp *data)
-{
-  if (data->error_string != NULL)
-    g_string_free (data->error_string, TRUE);
-
-  if (data->error_channel != NULL)
-    g_io_channel_unref (data->error_channel);
-
-  if (data->error_channel_source)
-    {
-      g_source_destroy (data->error_channel_source);
-      g_source_unref (data->error_channel_source);
-    }
-
-  if (data->error_fd != -1)
-    close (data->error_fd);
-
-  g_free (data);
-}
-
 static void
-eject_mount_cb (GPid     pid,
-                gint     status,
-                gpointer user_data)
+eject_mount_done (GObject      *source,
+                  GAsyncResult *result,
+                  gpointer      user_data)
 {
+  GSubprocess *subprocess = G_SUBPROCESS (source);
   GTask *task = user_data;
-  EjectMountOp *data = g_task_get_task_data (task);
-  
-  if (WEXITSTATUS (status) != 0)
-    {
-      g_task_return_new_error (task,
-                               G_IO_ERROR, 
-                               G_IO_ERROR_FAILED,
-                               "%s", data->error_string->str);
-    }
-  else
-    g_task_return_boolean (task, TRUE);
-  g_object_unref (task);
-}
+  GError *error = NULL;
+  gchar *stderr_str;
 
-static gboolean
-eject_mount_read_error (GIOChannel   *channel,
-                        GIOCondition  condition,
-                        gpointer      user_data)
-{
-  GTask *task = user_data;
-  EjectMountOp *data = g_task_get_task_data (task);
-  char buf[BUFSIZ];
-  gsize bytes_read;
-  GError *error;
-  GIOStatus status;
-
-  error = NULL;
-read:
-  status = g_io_channel_read_chars (channel, buf, sizeof (buf), &bytes_read, &error);
-  if (status == G_IO_STATUS_NORMAL)
-   {
-     g_string_append_len (data->error_string, buf, bytes_read);
-     if (bytes_read == sizeof (buf))
-        goto read;
-   }
-  else if (status == G_IO_STATUS_EOF)
-    g_string_append_len (data->error_string, buf, bytes_read);
-  else if (status == G_IO_STATUS_ERROR)
+  if (!g_subprocess_communicate_utf8_finish (subprocess, result, NULL, &stderr_str, &error))
     {
-      if (data->error_string->len > 0)
-        g_string_append (data->error_string, "\n");
-
-      g_string_append (data->error_string, error->message);
+      g_task_return_error (task, error);
       g_error_free (error);
-
-      if (data->error_channel_source)
-        {
-          g_source_unref (data->error_channel_source);
-          data->error_channel_source = NULL;
-        }
-      return FALSE;
+    }
+  else /* successful communication */
+    {
+      if (!g_subprocess_get_successful (subprocess))
+        /* ...but bad exit code */
+        g_task_return_new_error (task, G_IO_ERROR, G_IO_ERROR_FAILED, "%s", stderr_str);
+      else
+        /* ...and successful exit code */
+        g_task_return_boolean (task, TRUE);
+
+      g_free (stderr_str);
     }
 
-  return TRUE;
+  g_object_unref (task);
 }
 
 static void
-eject_mount_do (GVolume             *volume,
-                GCancellable        *cancellable,
-                GAsyncReadyCallback  callback,
-                gpointer             user_data,
-                char               **argv)
+eject_mount_do (GVolume              *volume,
+                GCancellable         *cancellable,
+                GAsyncReadyCallback   callback,
+                gpointer              user_data,
+                const gchar * const  *argv)
 {
-  GUnixVolume *unix_volume = G_UNIX_VOLUME (volume);
+  GSubprocess *subprocess;
+  GError *error = NULL;
   GTask *task;
-  EjectMountOp *data;
-  GPid child_pid;
-  GSource *child_watch;
-  GError *error;
-  
-  data = g_new0 (EjectMountOp, 1);
-  data->unix_volume = unix_volume;
-  data->error_fd = -1;
-  
-  task = g_task_new (unix_volume, cancellable, callback, user_data);
-  g_task_set_task_data (task, data, (GDestroyNotify) eject_mount_op_free);
-
-  error = NULL;
-  if (!g_spawn_async_with_pipes (NULL,         /* working dir */
-                                 argv,
-                                 NULL,         /* envp */
-                                 G_SPAWN_DO_NOT_REAP_CHILD|G_SPAWN_SEARCH_PATH,
-                                 NULL,         /* child_setup */
-                                 NULL,         /* user_data for child_setup */
-                                 &child_pid,
-                                 NULL,           /* standard_input */
-                                 NULL,           /* standard_output */
-                                 &(data->error_fd),
-                                 &error))
-    {
-      g_assert (error != NULL);
-      goto handle_error;
-    }
 
-  data->error_string = g_string_new ("");
+  task = g_task_new (volume, cancellable, callback, user_data);
 
-  data->error_channel = g_io_channel_unix_new (data->error_fd);
-  g_io_channel_set_flags (data->error_channel, G_IO_FLAG_NONBLOCK, &error);
-  if (error != NULL)
-    goto handle_error;
-
-  data->error_channel_source = g_io_create_watch (data->error_channel, G_IO_IN);
-  g_task_attach_source (task, data->error_channel_source,
-                        (GSourceFunc) eject_mount_read_error);
+  if (g_task_return_error_if_cancelled (task))
+    return;
 
-  child_watch = g_child_watch_source_new (child_pid);
-  g_task_attach_source (task, child_watch, (GSourceFunc) eject_mount_cb);
-  g_source_unref (child_watch);
+  subprocess = g_subprocess_newv (argv, G_SUBPROCESS_FLAGS_STDOUT_SILENCE | G_SUBPROCESS_FLAGS_STDERR_PIPE, 
&error);
+  g_assert_no_error (error);
 
-handle_error:
-  if (error != NULL)
-    {
-      g_task_return_error (task, error);
-      g_object_unref (task);
-    }
+  g_subprocess_communicate_utf8_async (subprocess, NULL,
+                                       g_task_get_cancellable (task),
+                                       eject_mount_done, task);
 }
 
-
 static void
 g_unix_volume_mount (GVolume            *volume,
                      GMountMountFlags    flags,
@@ -428,7 +328,7 @@ g_unix_volume_mount (GVolume            *volume,
                      gpointer             user_data)
 {
   GUnixVolume *unix_volume = G_UNIX_VOLUME (volume);
-  char *argv[] = { "mount", NULL, NULL };
+  const gchar *argv[] = { "mount", NULL, NULL };
 
   if (unix_volume->mount_path != NULL)
     argv[1] = unix_volume->mount_path;
@@ -454,7 +354,7 @@ g_unix_volume_eject (GVolume             *volume,
                      gpointer             user_data)
 {
   GUnixVolume *unix_volume = G_UNIX_VOLUME (volume);
-  char *argv[] = { "eject", NULL, NULL };
+  const gchar *argv[] = { "eject", NULL, NULL };
 
   argv[1] = unix_volume->device_path;