[ostree] admin prune: New builtin for cleaning up deployments and repo

[Colin Walters <walters src gnome org>]

commit 3f4d2233611e5b4c93606d6eac17dc15b70e3b80
Author: Colin Walters <walters verbum org>
Date:   Fri Nov 16 17:41:46 2012 -0500

    admin prune: New builtin for cleaning up deployments and repo
    
    After a while of pull-deploy cycles, you start to accumulate a lot of
    them.  While the deployment read-only part is hardlinked, the -etc
    space adds up.
    
    Additionally, the repository itself just gets large.
    
    The new command "ostree admin prune" deletes everything except the
    "current" and "previous" deployments.

 Makefile-ostree.am                  |    1 +
 src/ostree/ot-admin-builtin-prune.c |  179 +++++++++++++++++++++++++++++++++++
 src/ostree/ot-admin-builtins.h      |    1 +
 src/ostree/ot-admin-functions.c     |   21 ++++
 src/ostree/ot-admin-functions.h     |    4 +
 src/ostree/ot-builtin-admin.c       |    1 +
 6 files changed, 207 insertions(+), 0 deletions(-)
---
diff --git a/Makefile-ostree.am b/Makefile-ostree.am
index 519f77a..2bff6c9 100644
--- a/Makefile-ostree.am
+++ b/Makefile-ostree.am
@@ -49,6 +49,7 @@ ostree_SOURCES += \
 	src/ostree/ot-admin-builtin-init.c \
 	src/ostree/ot-admin-builtin-diff.c \
 	src/ostree/ot-admin-builtin-deploy.c \
+	src/ostree/ot-admin-builtin-prune.c \
 	src/ostree/ot-admin-builtin-pull-deploy.c \
 	src/ostree/ot-admin-builtin-update-kernel.c \
 	src/ostree/ot-admin-builtins.h \
diff --git a/src/ostree/ot-admin-builtin-prune.c b/src/ostree/ot-admin-builtin-prune.c
new file mode 100644
index 0000000..5551644
--- /dev/null
+++ b/src/ostree/ot-admin-builtin-prune.c
@@ -0,0 +1,179 @@
+/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*-
+ *
+ * Copyright (C) 2012 Colin Walters <walters verbum org>
+ *
+ * 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 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., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ *
+ * Author: Colin Walters <walters verbum org>
+ */
+
+#include "config.h"
+
+#include "ot-admin-builtins.h"
+#include "ot-admin-functions.h"
+#include "ostree.h"
+
+#include <glib/gi18n.h>
+
+static gboolean opt_no_repo_prune;
+
+static GOptionEntry options[] = {
+  { "no-repo-prune", 0, 0, G_OPTION_ARG_NONE, &opt_no_repo_prune, "Only prune deployment checkouts; don't prune repository", NULL },
+  { NULL }
+};
+
+static gboolean
+list_deployments (GFile        *from_dir,
+                  GPtrArray    *inout_deployments,
+                  GCancellable *cancellable,
+                  GError      **error)
+{
+  gboolean ret = FALSE;
+  GError *temp_error = NULL;
+  ot_lobj GFileEnumerator *dir_enum = NULL;
+  ot_lobj GFileInfo *file_info = NULL;
+
+  dir_enum = g_file_enumerate_children (from_dir, OSTREE_GIO_FAST_QUERYINFO,
+                                        G_FILE_QUERY_INFO_NOFOLLOW_SYMLINKS,
+                                        NULL, error);
+  if (!dir_enum)
+    goto out;
+
+  while ((file_info = g_file_enumerator_next_file (dir_enum, cancellable, error)) != NULL)
+    {
+      const char *name;
+      ot_lobj GFile *child = NULL;
+      ot_lobj GFile *possible_etc = NULL;
+      ot_lobj GFile *possible_usr = NULL;
+
+      name = g_file_info_get_name (file_info);
+
+      if (g_str_has_suffix (name, "-etc"))
+        goto next;
+      if (g_file_info_get_file_type (file_info) != G_FILE_TYPE_DIRECTORY)
+        goto next;
+
+      child = g_file_get_child (from_dir, name);
+
+      possible_etc = ot_gfile_get_child_strconcat (from_dir, name, "-etc", NULL);
+      /* Bit of a hack... */
+      possible_usr = g_file_get_child (child, "usr");
+
+      if (g_file_query_exists (possible_etc, cancellable))
+        g_ptr_array_add (inout_deployments, g_file_get_child (from_dir, name));
+      else if (g_file_query_exists (possible_usr, cancellable))
+        goto next;
+      else
+        {
+          if (!list_deployments (child, inout_deployments,
+                                 cancellable, error))
+            goto out;
+        }
+
+    next:
+      g_clear_object (&file_info);
+    }
+  if (temp_error != NULL)
+    {
+      g_propagate_error (error, temp_error);
+      goto out;
+    }
+
+  ret = TRUE;
+ out:
+  return ret;
+}
+
+gboolean
+ot_admin_builtin_prune (int argc, char **argv, GFile *ostree_dir, GError **error)
+{
+  GOptionContext *context;
+  gboolean ret = FALSE;
+  guint i;
+  ot_lobj GFile *repo_path = NULL;
+  ot_lobj GFile *current_deployment = NULL;
+  ot_lobj GFile *previous_deployment = NULL;
+  ot_lptrarray GPtrArray *deployments = NULL;
+  __attribute__((unused)) GCancellable *cancellable = NULL;
+
+  context = g_option_context_new ("- Delete untagged deployments and repository objects");
+
+  g_option_context_add_main_entries (context, options, NULL);
+
+  if (!g_option_context_parse (context, &argc, &argv, error))
+    goto out;
+
+  if (!ot_admin_ensure_initialized (ostree_dir, cancellable, error))
+    goto out;
+
+  deployments = g_ptr_array_new_with_free_func ((GDestroyNotify) g_object_unref);
+  if (!list_deployments (ostree_dir, deployments, cancellable, error))
+    goto out;
+
+  if (!ot_admin_get_current_deployment (ostree_dir, &current_deployment,
+                                        cancellable, error));
+  if (!ot_admin_get_previous_deployment (ostree_dir, &previous_deployment,
+                                         cancellable, error));
+
+  for (i = 0; i < deployments->len; i++)
+    {
+      GFile *deployment = deployments->pdata[i];
+      ot_lobj GFile *deployment_etc = NULL;
+      ot_lobj GFile *parent = NULL;
+
+      if ((current_deployment && g_file_equal (deployment, current_deployment))
+          || (previous_deployment && g_file_equal (deployment, previous_deployment)))
+        continue;
+
+      parent = g_file_get_parent (deployment);
+      deployment_etc = ot_gfile_get_child_strconcat (parent, ot_gfile_get_basename_cached (deployment),
+                                                     "-etc", NULL);
+      
+      g_print ("Deleting deployment %s\n", ot_gfile_get_path_cached (deployment));
+      if (!ot_gio_shutil_rm_rf (deployment, cancellable, error))
+        goto out;
+      /* Note - not atomic; we may be leaving the -etc directory around
+       * if this fails in the middle =/
+       */
+      if (!ot_gio_shutil_rm_rf (deployment_etc, cancellable, error))
+        goto out;
+    }
+  
+  repo_path = g_file_get_child (ostree_dir, "repo");
+
+  if (!opt_no_repo_prune)
+    {
+      ot_lptrarray GPtrArray *prune_argv = NULL;
+      ot_lfree char *repo_arg = NULL;
+
+      repo_arg = g_strconcat ("--repo=", ot_gfile_get_path_cached (repo_path), NULL);
+
+      prune_argv = g_ptr_array_new ();
+      ot_ptrarray_add_many (prune_argv, "ostree", repo_arg, "prune", "--refs-only", "--depth=0", NULL);
+      g_ptr_array_add (prune_argv, NULL);
+      
+      if (!ot_spawn_sync_checked (ot_gfile_get_path_cached (ostree_dir),
+                                  (char**)prune_argv->pdata, NULL, G_SPAWN_SEARCH_PATH,
+                                  NULL, NULL, NULL, NULL, error))
+        goto out;
+    }
+
+  ret = TRUE;
+ out:
+  if (context)
+    g_option_context_free (context);
+  return ret;
+}
diff --git a/src/ostree/ot-admin-builtins.h b/src/ostree/ot-admin-builtins.h
index ed38285..743c4c6 100644
--- a/src/ostree/ot-admin-builtins.h
+++ b/src/ostree/ot-admin-builtins.h
@@ -29,6 +29,7 @@ G_BEGIN_DECLS
 
 gboolean ot_admin_builtin_init (int argc, char **argv, GFile *ostree_dir, GError **error);
 gboolean ot_admin_builtin_deploy (int argc, char **argv, GFile *ostree_dir, GError **error);
+gboolean ot_admin_builtin_prune (int argc, char **argv, GFile *ostree_dir, GError **error);
 gboolean ot_admin_builtin_pull_deploy (int argc, char **argv, GFile *ostree_dir, GError **error);
 gboolean ot_admin_builtin_diff (int argc, char **argv, GFile *ostree_dir, GError **error);
 gboolean ot_admin_builtin_update_kernel (int argc, char **argv, GFile *ostree_dir, GError **error);
diff --git a/src/ostree/ot-admin-functions.c b/src/ostree/ot-admin-functions.c
index 85cd478..63c8266 100644
--- a/src/ostree/ot-admin-functions.c
+++ b/src/ostree/ot-admin-functions.c
@@ -194,3 +194,24 @@ ot_admin_get_current_deployment (GFile           *ostree_dir,
   return query_symlink_target_allow_noent (current_path, out_deployment,
                                            cancellable, error);
 }
+
+/**
+ * ot_admin_get_previous_deployment:
+ * 
+ * Returns in @out_deployment the full file path of the current
+ * deployment that the /ostree/previous symbolic link points to, or
+ * %NULL if none.
+ */
+gboolean
+ot_admin_get_previous_deployment (GFile           *ostree_dir,
+                                 GFile          **out_deployment,
+                                 GCancellable    *cancellable,
+                                 GError         **error)
+{
+  ot_lobj GFile *previous_path = NULL;
+
+  previous_path = g_file_get_child (ostree_dir, "previous");
+
+  return query_symlink_target_allow_noent (previous_path, out_deployment,
+                                           cancellable, error);
+}
diff --git a/src/ostree/ot-admin-functions.h b/src/ostree/ot-admin-functions.h
index f4e1b74..af114aa 100644
--- a/src/ostree/ot-admin-functions.h
+++ b/src/ostree/ot-admin-functions.h
@@ -35,6 +35,10 @@ gboolean ot_admin_get_current_deployment (GFile           *ostree_dir,
                                           GFile          **out_deployment,
                                           GCancellable    *cancellable,
                                           GError         **error);
+gboolean ot_admin_get_previous_deployment (GFile           *ostree_dir,
+                                           GFile          **out_deployment,
+                                           GCancellable    *cancellable,
+                                           GError         **error);
 
 G_END_DECLS
 
diff --git a/src/ostree/ot-builtin-admin.c b/src/ostree/ot-builtin-admin.c
index 70538af..869a134 100644
--- a/src/ostree/ot-builtin-admin.c
+++ b/src/ostree/ot-builtin-admin.c
@@ -46,6 +46,7 @@ static OstreeAdminCommand admin_subcommands[] = {
   { "init", ot_admin_builtin_init },
   { "deploy", ot_admin_builtin_deploy },
   { "pull-deploy", ot_admin_builtin_pull_deploy },
+  { "prune", ot_admin_builtin_prune },
   { "update-kernel", ot_admin_builtin_update_kernel },
   { "config-diff", ot_admin_builtin_diff },
   { NULL, NULL }