libsysprof-analyze: start on mount namespace APIs

The goal here is that we can try to reproduce to some degree the mount
namespace as the PID saw it, but also convert that to paths where we can
find the files on the host system.

src/libsysprof-analyze/sysprof-mount-namespace.c

@@ -0,0 +1,94 @@
+/* sysprof-mount-namespace.c
+ *
+ * Copyright 2023 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 "sysprof-mount-namespace-private.h"
+
+struct _SysprofMountNamespace
+{
+  GObject    parent_instance;
+  GPtrArray *devices;
+};
+
+G_DEFINE_FINAL_TYPE (SysprofMountNamespace, sysprof_mount_namespace, G_TYPE_OBJECT)
+
+static void
+sysprof_mount_namespace_finalize (GObject *object)
+{
+  SysprofMountNamespace *self = (SysprofMountNamespace *)object;
+
+  g_clear_pointer (&self->devices, g_ptr_array_unref);
+
+  G_OBJECT_CLASS (sysprof_mount_namespace_parent_class)->finalize (object);
+}
+
+static void
+sysprof_mount_namespace_class_init (SysprofMountNamespaceClass *klass)
+{
+  GObjectClass *object_class = G_OBJECT_CLASS (klass);
+
+  object_class->finalize = sysprof_mount_namespace_finalize;
+}
+
+static void
+sysprof_mount_namespace_init (SysprofMountNamespace *self)
+{
+  self->devices = g_ptr_array_new_with_free_func (g_object_unref);
+}
+
+SysprofMountNamespace *
+sysprof_mount_namespace_new (void)
+{
+  return g_object_new (SYSPROF_TYPE_MOUNT_NAMESPACE, NULL);
+}
+
+SysprofMountNamespace *
+sysprof_mount_namespace_copy (SysprofMountNamespace *self)
+{
+  SysprofMountNamespace *copy;
+
+  g_return_val_if_fail (SYSPROF_IS_MOUNT_NAMESPACE (self), NULL);
+
+  copy = sysprof_mount_namespace_new ();
+
+  for (guint i = 0; i < self->devices->len; i++)
+    sysprof_mount_namespace_add_device (copy, g_object_ref (g_ptr_array_index (self->devices, i)));
+
+  return copy;
+}
+
+/**
+ * sysprof_mount_namespace_add_device:
+ * @self: a #SysprofMountNamespace
+ * @device: (transfer full): a #SysprofMountDevice
+ *
+ * Adds information about where a device is mounted on the host for resolving
+ * paths to binaries.
+ */
+void
+sysprof_mount_namespace_add_device (SysprofMountNamespace *self,
+                                    SysprofMountDevice    *device)
+{
+  g_return_if_fail (SYSPROF_IS_MOUNT_NAMESPACE (self));
+  g_return_if_fail (SYSPROF_IS_MOUNT_DEVICE (device));
+
+  g_ptr_array_add (self->devices, device);
+}