WIP

Signed-off-by: Philip Withnall <withnall@endlessm.com>

libmalcontent/manager.c

@@ -29,6 +29,7 @@
 #include <libmalcontent/app-filter.h>
 #include <libmalcontent/manager.h>
 #include <libmalcontent/session-limits.h>
+#include <systemd/sd-journal.h>
 
 #include "libmalcontent/app-filter-private.h"
 #include "libmalcontent/session-limits-private.h"
@@ -1333,3 +1334,132 @@ mct_manager_set_session_limits_finish (MctManager    *self,
 
   return g_task_propagate_boolean (G_TASK (result), error);
 }
+
+G_DEFINE_AUTO_CLEANUP_CLEAR_FUNC (sd_journal, sd_journal_close)
+
+/* TODO Docs */
+MctSessionHistory *
+mct_manager_get_session_history (MctManager               *self,
+                                 uid_t                     user_id,
+                                 GDateTime                *start,
+                                 GDateTime                *end,
+                                 MctManagerGetValueFlags   flags,
+                                 GCancellable             *cancellable,
+                                 GError                  **error)
+{
+  g_auto(sd_journal) *journal = NULL;
+  int ret;
+  const gchar * const match_message_ids[] =
+    {
+      "MESSAGE_ID=8d45620c1a4348dbb17410da57c60c66",  /* new session */
+      "MESSAGE_ID=3354939424b4456d9802ca8333ed424a",  /* session ended */
+      "MESSAGE_ID=6bbd95ee977941e497c48be27c254128",  /* entering sleep */
+      "MESSAGE_ID=8811e6df2a8e40f58a94cea26f8ebf14",  /* leaving sleep */
+      "MESSAGE_ID=b07a249cd024414a82dd00cd181378ff",  /* startup complete */
+      "MESSAGE_ID=98268866d1d54a499c4e98921d93bc40",  /* starting to shut down */
+      /* TODO: need to add messages to gnome-shell for when the user locks and unlocks the screen,
+       * including logging in and out and switching user */
+    };
+  const size_t message_id_len = sizeof (match_message_ids[0]);
+  g_autoptr(GPtrArray) active_periods = g_ptr_array_new_with_free_func (NULL);  /* TODO */
+
+  g_return_val_if_fail (MCT_IS_MANAGER (self), NULL);
+  g_return_val_if_fail (start != NULL, NULL);
+  g_return_val_if_fail (end != NULL, NULL);
+  g_return_val_if_fail (cancellable == NULL || G_IS_CANCELLABLE (cancellable), NULL);
+  g_return_val_if_fail (error == NULL || *error == NULL, NULL);
+
+  ret = sd_journal_open (&journal, SD_JOURNAL_SYSTEM);
+  if (ret < 0)
+    {
+      g_set_error (error, G_IO_ERROR, G_IO_ERROR_FAILED,
+                   "Error opening journal: %s", g_strerror (-ret));
+      return NULL;
+    }
+
+  /* TODO: work out what data threshold is needed and set with sd_journal_set_data_threshold() */
+
+  /* Add matches. */
+  for (gsize i = 0; i < G_N_ELEMENTS (match_message_ids); i++)
+    {
+      ret = sd_journal_add_match (journal, "MESSAGE_ID=TODO", 0);
+      if (ret < 0)
+        {
+          g_set_error (error, G_IO_ERROR, G_IO_ERROR_FAILED,  /* TODO More specific error codes throughout */
+                       "Error applying matches in journal: %s", g_strerror (-ret));
+          return NULL;
+        }
+    }
+
+  ret = sd_journal_seek_realtime_usec (journal, (uint64_t) g_date_time_to_unix (start) * G_USEC_PER_SEC);
+  if (ret < 0)
+    {
+      g_set_error (error, G_IO_ERROR, G_IO_ERROR_FAILED,  /* TODO More specific error codes throughout */
+                   "Error finding start entry in journal: %s", g_strerror (-ret));
+      return NULL;
+    }
+
+  while (TRUE)
+    {
+      uint64_t entry_realtime = 0;
+      const void *data = NULL;
+      size_t data_len = 0;
+
+      ret = sd_journal_next (journal);
+      if (ret < 0)
+        {
+          g_set_error (error, G_IO_ERROR, G_IO_ERROR_FAILED,
+                       "Error seeking journal: %s", g_strerror (-ret));
+          return NULL;
+        }
+      else if (ret == 0)
+        {
+          /* Reached EOF. */
+          break;
+        }
+
+      ret = sd_journal_get_realtime_usec (journal, &entry_realtime);
+      if (ret < 0)
+        {
+          g_set_error (error, G_IO_ERROR, G_IO_ERROR_FAILED,
+                       "Error reading journal: %s", g_strerror (-ret));
+          return NULL;
+        }
+
+      if (entry_realtime / G_USEC_PER_SEC >= g_date_time_to_unix (end))
+        {
+          /* Reached the end of the search range. */
+          break;
+        }
+
+      /* Check the type of the record. */
+      ret = sd_journal_get_data (journal, "MESSAGE_ID", &data, &data_len);
+      if (ret < 0)
+        {
+          g_set_error (error, G_IO_ERROR, G_IO_ERROR_FAILED,
+                       "Error reading journal: %s", g_strerror (-ret));
+          return NULL;
+        }
+
+      if (data_len != message_id_len)
+        {
+          g_debug ("Unexpected field %s, ignoring", data);
+          continue;
+        }
+
+      /* TODO: need to filter by uid */
+      if (memcmp (data, "MESSAGE_ID=8d45620c1a4348dbb17410da57c60c66", message_id_len) == 0)
+        {
+          /* New session. */
+          g_ptr_array_add (active_periods, TODO);
+        }
+
+/* TODO */
+      "MESSAGE_ID=3354939424b4456d9802ca8333ed424a",  /* session ended */
+      "MESSAGE_ID=6bbd95ee977941e497c48be27c254128",  /* entering sleep */
+      "MESSAGE_ID=8811e6df2a8e40f58a94cea26f8ebf14",  /* leaving sleep */
+      "MESSAGE_ID=b07a249cd024414a82dd00cd181378ff",  /* startup complete */
+      "MESSAGE_ID=98268866d1d54a499c4e98921d93bc40",  /* starting to shut down */
+
+    }
+}

libmalcontent/manager.h

@@ -168,4 +168,13 @@ gboolean      mct_manager_set_session_limits_finish (MctManager                *
                                                      GAsyncResult              *result,
                                                      GError                   **error);
 
+/* TODO */
+MctSessionHistory *mct_manager_get_session_history (MctManager               *self,
+                                                    uid_t                     user_id,
+                                                    GDateTime                *start,
+                                                    GDateTime                *end,
+                                                    MctManagerGetValueFlags   flags,
+                                                    GCancellable             *cancellable,
+                                                    GError                  **error);
+
 G_END_DECLS

libmalcontent/meson.build

@@ -3,16 +3,19 @@ libmalcontent_api_name = 'malcontent-' + libmalcontent_api_version
 libmalcontent_sources = [
   'app-filter.c',
   'manager.c',
+  'session-history.c',
   'session-limits.c',
 ]
 libmalcontent_headers = [
   'app-filter.h',
   'malcontent.h',
   'manager.h',
+  'session-history.h',
   'session-limits.h',
 ]
 libmalcontent_private_headers = [
   'app-filter-private.h',
+  'session-history-private.h',
   'session-limits-private.h',
 ]
 
@@ -68,4 +71,4 @@ gnome.generate_gir(libmalcontent,
   dependencies: libmalcontent_dep,
 )
 
-subdir('tests')
+subdir('tests')

libmalcontent/session-history-private.h

@@ -0,0 +1,42 @@
+/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*-
+ *
+ * Copyright © 2020 Endless Mobile, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ * Authors:
+ *  - Philip Withnall <withnall@endlessm.com>
+ */
+
+#pragma once
+
+#include <gio/gio.h>
+#include <glib.h>
+#include <glib-object.h>
+#include <libmalcontent/session-history.h>
+
+G_BEGIN_DECLS
+
+struct _MctSessionHistory
+{
+  gint ref_count;
+
+  uid_t user_id;
+
+  GDateTime *start;  /* (owned) */
+  GDateTime *end;  /* (owned) */
+};
+
+G_END_DECLS

libmalcontent/session-history.c

@@ -0,0 +1,100 @@
+/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*-
+ *
+ * Copyright © 2020 Endless Mobile, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ * Authors:
+ *  - Philip Withnall <withnall@endlessm.com>
+ */
+
+#include "config.h"
+
+#include <glib.h>
+#include <glib-object.h>
+#include <glib/gi18n-lib.h>
+#include <gio/gio.h>
+#include <libmalcontent/session-history.h>
+
+#include "libmalcontent/session-history-private.h"
+
+
+/* struct _MctSessionHistory is defined in session-history-private.h */
+
+G_DEFINE_BOXED_TYPE (MctSessionHistory, mct_session_history,
+                     mct_session_history_ref, mct_session_history_unref)
+
+/**
+ * mct_session_history_ref:
+ * @history: (transfer none): an #MctSessionHistory
+ *
+ * Increment the reference count of @history, and return the same pointer to it.
+ *
+ * Returns: (transfer full): the same pointer as @history
+ * Since: 0.5.0
+ */
+MctSessionHistory *
+mct_session_history_ref (MctSessionHistory *history)
+{
+  g_return_val_if_fail (history != NULL, NULL);
+  g_return_val_if_fail (history->ref_count >= 1, NULL);
+  g_return_val_if_fail (history->ref_count <= G_MAXINT - 1, NULL);
+
+  history->ref_count++;
+  return history;
+}
+
+/**
+ * mct_session_history_unref:
+ * @history: (transfer full): an #MctSessionHistory
+ *
+ * Decrement the reference count of @history. If the reference count reaches
+ * zero, free the @history and all its resources.
+ *
+ * Since: 0.5.0
+ */
+void
+mct_session_history_unref (MctSessionHistory *history)
+{
+  g_return_if_fail (history != NULL);
+  g_return_if_fail (history->ref_count >= 1);
+
+  history->ref_count--;
+
+  if (history->ref_count <= 0)
+    {
+      g_clear_pointer (&history->start, g_date_time_unref);
+      g_clear_pointer (&history->end, g_date_time_unref);
+      g_free (history);
+    }
+}
+
+/**
+ * mct_session_history_get_user_id:
+ * @history: an #MctSessionHistory
+ *
+ * Get the user ID of the user this #MctSessionHistory is for.
+ *
+ * Returns: user ID of the relevant user
+ * Since: 0.5.0
+ */
+uid_t
+mct_session_history_get_user_id (MctSessionHistory *history)
+{
+  g_return_val_if_fail (history != NULL, (uid_t) -1);
+  g_return_val_if_fail (history->ref_count >= 1, (uid_t) -1);
+
+  return history->user_id;
+}

libmalcontent/session-history.h

@@ -0,0 +1,59 @@
+/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*-
+ *
+ * Copyright © 2020 Endless Mobile, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ * Authors:
+ *  - Philip Withnall <withnall@endlessm.com>
+ */
+
+#pragma once
+
+#include <gio/gio.h>
+#include <glib.h>
+#include <glib-object.h>
+
+G_BEGIN_DECLS
+
+/**
+ * MctSessionHistory:
+ *
+ * TODO
+ * #MctSessionLimits is an opaque, immutable structure which contains a snapshot
+ * of the session limits settings for a user at a given time. This includes
+ * whether session limits are being enforced, and the limit policy — for
+ * example, the times of day when a user is allowed to use the computer.
+ *
+ * Typically, session limits settings can only be changed by the administrator,
+ * and are read-only for non-administrative users. The precise policy is set
+ * using polkit.
+ *
+ * Since: 0.5.0
+ */
+typedef struct _MctSessionHistory MctSessionHistory;
+GType mct_session_history_get_type (void);
+#define MCT_TYPE_SESSION_HISTORY mct_session_history_get_type ()
+
+MctSessionHistory *mct_session_history_ref   (MctSessionHistory *history);
+void              mct_session_history_unref (MctSessionHistory *history);
+
+G_DEFINE_AUTOPTR_CLEANUP_FUNC (MctSessionHistory, mct_session_history_unref)
+
+uid_t      mct_session_history_get_user_id          (MctSessionHistory *history);
+GDateTime *mct_session_history_get_start            (MctSessionHistory *history);
+GDateTime *mct_session_history_get_end              (MctSessionHistory *history);
+
+G_END_DECLS