libsysprof-profile: bring over mapped ring buffer source

src/libsysprof-profile/mapped-ring-buffer-source-private.h

@@ -0,0 +1,41 @@
+/* mapped-ring-buffer-source-private.h
+ *
+ * Copyright 2020 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/>.
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
+#pragma once
+
+#include <glib.h>
+
+#include "mapped-ring-buffer.h"
+
+G_BEGIN_DECLS
+
+G_DEFINE_AUTOPTR_CLEANUP_FUNC (MappedRingBuffer, mapped_ring_buffer_unref)
+
+G_GNUC_INTERNAL
+guint mapped_ring_buffer_create_source      (MappedRingBuffer         *self,
+                                             MappedRingBufferCallback  callback,
+                                             gpointer                  user_data);
+G_GNUC_INTERNAL
+guint mapped_ring_buffer_create_source_full (MappedRingBuffer         *self,
+                                             MappedRingBufferCallback  callback,
+                                             gpointer                  user_data,
+                                             GDestroyNotify            destroy);
+
+G_END_DECLS

src/libsysprof-profile/mapped-ring-buffer-source.c

@@ -0,0 +1,119 @@
+/* mapped-ring-buffer-source.c
+ *
+ * Copyright 2020 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/>.
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
+#include "config.h"
+
+#include <glib.h>
+
+#include "mapped-ring-buffer-source-private.h"
+
+typedef struct _MappedRingSource
+{
+  GSource           source;
+  MappedRingBuffer *buffer;
+} MappedRingSource;
+
+static gboolean
+mapped_ring_source_dispatch (GSource     *source,
+                             GSourceFunc  callback,
+                             gpointer     user_data)
+{
+  MappedRingSource *real_source = (MappedRingSource *)source;
+
+  g_assert (source != NULL);
+
+  return mapped_ring_buffer_drain (real_source->buffer,
+                                   (MappedRingBufferCallback)callback,
+                                   user_data);
+}
+
+static void
+mapped_ring_source_finalize (GSource *source)
+{
+  MappedRingSource *real_source = (MappedRingSource *)source;
+
+  if (real_source != NULL)
+    g_clear_pointer (&real_source->buffer, mapped_ring_buffer_unref);
+}
+
+static gboolean
+mapped_ring_source_check (GSource *source)
+{
+  MappedRingSource *real_source = (MappedRingSource *)source;
+
+  g_assert (real_source != NULL);
+  g_assert (real_source->buffer != NULL);
+
+  return !mapped_ring_buffer_is_empty (real_source->buffer);
+}
+
+static gboolean
+mapped_ring_source_prepare (GSource *source,
+                            gint    *timeout_)
+{
+  MappedRingSource *real_source = (MappedRingSource *)source;
+
+  g_assert (real_source != NULL);
+  g_assert (real_source->buffer != NULL);
+
+  if (!mapped_ring_buffer_is_empty (real_source->buffer))
+    return TRUE;
+
+  *timeout_ = 5;
+
+  return FALSE;
+}
+
+static GSourceFuncs mapped_ring_source_funcs = {
+  .prepare  = mapped_ring_source_prepare,
+  .check    = mapped_ring_source_check,
+  .dispatch = mapped_ring_source_dispatch,
+  .finalize = mapped_ring_source_finalize,
+};
+
+guint
+mapped_ring_buffer_create_source_full (MappedRingBuffer         *self,
+                                       MappedRingBufferCallback  source_func,
+                                       gpointer                  user_data,
+                                       GDestroyNotify            destroy)
+{
+  MappedRingSource *source;
+  guint ret;
+
+  g_return_val_if_fail (self != NULL, 0);
+  g_return_val_if_fail (source_func != NULL, 0);
+
+  source = (MappedRingSource *)g_source_new (&mapped_ring_source_funcs, sizeof (MappedRingSource));
+  source->buffer = mapped_ring_buffer_ref (self);
+  g_source_set_callback ((GSource *)source, (GSourceFunc)source_func, user_data, destroy);
+  g_source_set_name ((GSource *)source, "MappedRingSource");
+  ret = g_source_attach ((GSource *)source, g_main_context_default ());
+  g_source_unref ((GSource *)source);
+
+  return ret;
+}
+
+guint
+mapped_ring_buffer_create_source (MappedRingBuffer         *self,
+                                  MappedRingBufferCallback  source_func,
+                                  gpointer                  user_data)
+{
+  return mapped_ring_buffer_create_source_full (self, source_func, user_data, NULL);
+}

src/libsysprof-profile/meson.build

@@ -6,6 +6,7 @@ libsysprof_profile_public_sources = [
 ]
 
 libsysprof_profile_private_sources = [
+  'mapped-ring-buffer-source.c',
   'sysprof-controlfd-instrument.c',
   'sysprof-polkit.c',
 ]