/* -*- 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 "ostree-sysroot-private.h"
#include "otutil.h"
#include "libgsystem.h"

/**
 * copy_one_config_file:
 *
 * Copy @file from @modified_etc to @new_etc, overwriting any existing
 * file there.
 */
static gboolean
copy_one_config_file (GFile              *orig_etc,
                      GFile              *modified_etc,
                      GFile              *new_etc,
                      GFile              *src,
                      GCancellable       *cancellable,
                      GError            **error)
{
  gboolean ret = FALSE;
  gs_unref_object GFileInfo *src_info = NULL;
  gs_unref_object GFile *dest = NULL;
  gs_unref_object GFile *parent = NULL;
  gs_free char *relative_path = NULL;
  
  relative_path = g_file_get_relative_path (modified_etc, src);
  g_assert (relative_path);
  dest = g_file_resolve_relative_path (new_etc, relative_path);

  src_info = g_file_query_info (src, OSTREE_GIO_FAST_QUERYINFO, G_FILE_QUERY_INFO_NOFOLLOW_SYMLINKS,
                                cancellable, error);
  if (!src_info)
    goto out;

  if (g_file_info_get_file_type (src_info) == G_FILE_TYPE_DIRECTORY)
    {
      gs_unref_object GFileEnumerator *src_enum = NULL;
      gs_unref_object GFileInfo *child_info = NULL;
      GError *temp_error = NULL;

      /* FIXME actually we need to copy permissions and xattrs */
      if (!gs_file_ensure_directory (dest, TRUE, cancellable, error))
        goto out;

      src_enum = g_file_enumerate_children (src, OSTREE_GIO_FAST_QUERYINFO,
                                            G_FILE_QUERY_INFO_NOFOLLOW_SYMLINKS,
                                            cancellable, error);

      while ((child_info = g_file_enumerator_next_file (src_enum, cancellable, error)) != NULL)
        {
          gs_unref_object GFile *child = g_file_get_child (src, g_file_info_get_name (child_info));

          if (!copy_one_config_file (orig_etc, modified_etc, new_etc, child,
                                     cancellable, error))
            goto out;
        }
      g_clear_object (&child_info);
      if (temp_error != NULL)
        {
          g_propagate_error (error, temp_error);
          goto out;
        }
    }
  else
    {
      parent = g_file_get_parent (dest);

      /* FIXME actually we need to copy permissions and xattrs */
      if (!gs_file_ensure_directory (parent, TRUE, cancellable, error))
        goto out;
      
      /* We unlink here because otherwise gio throws an error on
       * dangling symlinks.
       */
      if (!ot_gfile_ensure_unlinked (dest, cancellable, error))
        goto out;

      if (!g_file_copy (src, dest, G_FILE_COPY_OVERWRITE | G_FILE_COPY_NOFOLLOW_SYMLINKS | G_FILE_COPY_ALL_METADATA,
                        cancellable, NULL, NULL, error))
        goto out;
    }

  ret = TRUE;
 out:
  return ret;
}

/**
 * merge_etc_changes:
 *
 * Compute the difference between @orig_etc and @modified_etc,
 * and apply that to @new_etc.
 *
 * The algorithm for computing the difference is pretty simple; it's
 * approximately equivalent to "diff -unR orig_etc modified_etc",
 * except that rather than attempting a 3-way merge if a file is also
 * changed in @new_etc, the modified version always wins.
 */
static gboolean
merge_etc_changes (GFile          *orig_etc,
                   GFile          *modified_etc,
                   GFile          *new_etc,
                   GCancellable   *cancellable,
                   GError        **error)
{
  gboolean ret = FALSE;
  gs_unref_ptrarray GPtrArray *modified = NULL;
  gs_unref_ptrarray GPtrArray *removed = NULL;
  gs_unref_ptrarray GPtrArray *added = NULL;
  guint i;

  modified = g_ptr_array_new_with_free_func ((GDestroyNotify) ostree_diff_item_unref);
  removed = g_ptr_array_new_with_free_func ((GDestroyNotify) g_object_unref);
  added = g_ptr_array_new_with_free_func ((GDestroyNotify) g_object_unref);

  if (!ostree_diff_dirs (orig_etc, modified_etc, modified, removed, added,
                         cancellable, error))
    {
      g_prefix_error (error, "While computing configuration diff: ");
      goto out;
    }

  if (modified->len > 0 || removed->len > 0 || added->len > 0)
    g_print ("ostadmin: Processing config: %u modified, %u removed, %u added\n", 
             modified->len,
             removed->len,
             added->len);
  else
    g_print ("ostadmin: No modified configuration\n");

  for (i = 0; i < removed->len; i++)
    {
      GFile *file = removed->pdata[i];
      gs_unref_object GFile *target_file = NULL;
      gs_free char *path = NULL;

      path = g_file_get_relative_path (orig_etc, file);
      g_assert (path);
      target_file = g_file_resolve_relative_path (new_etc, path);

      if (!ot_gfile_ensure_unlinked (target_file, cancellable, error))
        goto out;
    }

  for (i = 0; i < modified->len; i++)
    {
      OstreeDiffItem *diff = modified->pdata[i];

      if (!copy_one_config_file (orig_etc, modified_etc, new_etc, diff->target,
                                 cancellable, error))
        goto out;
    }
  for (i = 0; i < added->len; i++)
    {
      GFile *file = added->pdata[i];

      if (!copy_one_config_file (orig_etc, modified_etc, new_etc, file,
                                 cancellable, error))
        goto out;
    }

  ret = TRUE;
 out:
  return ret;
}

/**
 * checkout_deployment_tree:
 *
 * Look up @revision in the repository, and check it out in
 * /ostree/deploy/OS/deploy/${treecsum}.${deployserial}.
 */
static gboolean
checkout_deployment_tree (OstreeSysroot     *sysroot,
                          OstreeRepo        *repo,
                          OstreeDeployment      *deployment,
                          GFile            **out_deployment_path,
                          GCancellable      *cancellable,
                          GError           **error)
{
  gboolean ret = FALSE;
  const char *csum = ostree_deployment_get_csum (deployment);
  gs_unref_object GFile *root = NULL;
  gs_unref_object GFileInfo *file_info = NULL;
  gs_free char *checkout_target_name = NULL;
  gs_unref_object GFile *osdeploy_path = NULL;
  gs_unref_object GFile *deploy_target_path = NULL;
  gs_unref_object GFile *deploy_parent = NULL;

  if (!ostree_repo_read_commit (repo, csum, &root, NULL, cancellable, error))
    goto out;

  file_info = g_file_query_info (root, OSTREE_GIO_FAST_QUERYINFO,
                                 G_FILE_QUERY_INFO_NOFOLLOW_SYMLINKS,
                                 cancellable, error);
  if (!file_info)
    goto out;

  osdeploy_path = ot_gfile_get_child_build_path (sysroot->path, "ostree", "deploy",
                                                 ostree_deployment_get_osname (deployment),
                                                 "deploy", NULL);
  checkout_target_name = g_strdup_printf ("%s.%d", csum, ostree_deployment_get_deployserial (deployment));
  deploy_target_path = g_file_get_child (osdeploy_path, checkout_target_name);

  deploy_parent = g_file_get_parent (deploy_target_path);
  if (!gs_file_ensure_directory (deploy_parent, TRUE, cancellable, error))
    goto out;
  
  g_print ("ostadmin: Creating deployment %s\n",
           gs_file_get_path_cached (deploy_target_path));

  if (!ostree_repo_checkout_tree (repo, 0, 0, deploy_target_path, OSTREE_REPO_FILE (root),
                                  file_info, cancellable, error))
    goto out;

  ret = TRUE;
  ot_transfer_out_value (out_deployment_path, &deploy_target_path);
 out:
  return ret;
}

static gboolean
merge_configuration (OstreeSysroot         *sysroot,
                     OstreeDeployment      *previous_deployment,
                     OstreeDeployment      *deployment,
                     GFile             *deployment_path,
                     GCancellable      *cancellable,
                     GError           **error)
{
  gboolean ret = FALSE;
  gs_unref_object GFile *source_etc_path = NULL;
  gs_unref_object GFile *source_etc_pristine_path = NULL;
  gs_unref_object GFile *deployment_usretc_path = NULL;
  gs_unref_object GFile *deployment_etc_path = NULL;
  gboolean etc_exists;
  gboolean usretc_exists;

  if (previous_deployment)
    {
      gs_unref_object GFile *previous_path = NULL;
      OstreeBootconfigParser *previous_bootconfig;

      previous_path = ostree_sysroot_get_deployment_directory (sysroot, previous_deployment);
      source_etc_path = g_file_resolve_relative_path (previous_path, "etc");
      source_etc_pristine_path = g_file_resolve_relative_path (previous_path, "usr/etc");

      previous_bootconfig = ostree_deployment_get_bootconfig (previous_deployment);
      if (previous_bootconfig)
        {
          const char *previous_options = ostree_bootconfig_parser_get (previous_bootconfig, "options");
          /* Completely overwrite the previous options here; we will extend
           * them later.
           */
          ostree_bootconfig_parser_set (ostree_deployment_get_bootconfig (deployment), "options",
                                        previous_options);
        }
    }

  deployment_etc_path = g_file_get_child (deployment_path, "etc");
  deployment_usretc_path = g_file_resolve_relative_path (deployment_path, "usr/etc");
  
  etc_exists = g_file_query_exists (deployment_etc_path, NULL);
  usretc_exists = g_file_query_exists (deployment_usretc_path, NULL);

  if (etc_exists && usretc_exists)
    {
      g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_NOT_FOUND,
                           "Tree contains both /etc and /usr/etc");
      goto out;
    }
  else if (etc_exists)
    {
      /* Compatibility hack */
      if (!gs_file_rename (deployment_etc_path, deployment_usretc_path,
                           cancellable, error))
        goto out;
      usretc_exists = TRUE;
      etc_exists = FALSE;
    }
  
  if (usretc_exists)
    {
      g_assert (!etc_exists);
      if (!gs_shutil_cp_a (deployment_usretc_path, deployment_etc_path,
                           cancellable, error))
        goto out;
      g_print ("ostadmin: Created %s\n", gs_file_get_path_cached (deployment_etc_path));
    }

  if (source_etc_path)
    {
      if (!merge_etc_changes (source_etc_pristine_path, source_etc_path, deployment_etc_path, 
                              cancellable, error))
        goto out;
    }
  else
    {
      g_print ("ostadmin: No previous configuration changes to merge\n");
    }

  ret = TRUE;
 out:
  return ret;
}

static gboolean
write_origin_file (OstreeSysroot         *sysroot,
                   OstreeDeployment      *deployment,
                   GCancellable      *cancellable,
                   GError           **error)
{
  gboolean ret = FALSE;
  GKeyFile *origin = ostree_deployment_get_origin (deployment);

  if (origin)
    {
      gs_unref_object GFile *deployment_path = ostree_sysroot_get_deployment_directory (sysroot, deployment);
      gs_unref_object GFile *origin_path = ostree_sysroot_get_deployment_origin_path (deployment_path);
      gs_free char *contents = NULL;
      gsize len;

      contents = g_key_file_to_data (origin, &len, error);
      if (!contents)
        goto out;

      if (!g_file_replace_contents (origin_path, contents, len, NULL, FALSE,
                                    G_FILE_CREATE_REPLACE_DESTINATION, NULL,
                                    cancellable, error))
        goto out;
    }

  ret = TRUE;
 out:
  return ret;
}

static gboolean
get_kernel_from_tree (GFile         *deployroot,
                      GFile        **out_kernel,
                      GFile        **out_initramfs,
                      GCancellable  *cancellable,
                      GError       **error)
{
  gboolean ret = FALSE;
  gs_unref_object GFile *bootdir = g_file_get_child (deployroot, "boot");
  gs_unref_object GFileEnumerator *dir_enum = NULL;
  gs_unref_object GFile *ret_kernel = NULL;
  gs_unref_object GFile *ret_initramfs = NULL;
  gs_free char *kernel_checksum = NULL;
  gs_free char *initramfs_checksum = NULL;

  dir_enum = g_file_enumerate_children (bootdir, OSTREE_GIO_FAST_QUERYINFO,
                                        G_FILE_QUERY_INFO_NOFOLLOW_SYMLINKS,
                                        NULL, error);
  if (!dir_enum)
    goto out;

  while (TRUE)
    {
      GFileInfo *file_info = NULL;
      const char *name;

      if (!gs_file_enumerator_iterate (dir_enum, &file_info, NULL,
                                       cancellable, error))
        goto out;
      if (file_info == NULL)
        break;

      name = g_file_info_get_name (file_info);
      
      if (ret_kernel == NULL && g_str_has_prefix (name, "vmlinuz-"))
        {
          const char *dash = strrchr (name, '-');
          g_assert (dash);
          if (ostree_validate_structureof_checksum_string (dash + 1, NULL))
            {
              kernel_checksum = g_strdup (dash + 1);
              ret_kernel = g_file_get_child (bootdir, name);
            }
        }
      else if (ret_initramfs == NULL && g_str_has_prefix (name, "initramfs-"))
        {
          const char *dash = strrchr (name, '-');
          g_assert (dash);
          if (ostree_validate_structureof_checksum_string (dash + 1, NULL))
            {
              initramfs_checksum = g_strdup (dash + 1);
              ret_initramfs = g_file_get_child (bootdir, name);
            }
        }
      
      if (ret_kernel && ret_initramfs)
        break;
    }

  if (ret_kernel == NULL)
    {
      g_set_error (error, G_IO_ERROR, G_IO_ERROR_NOT_FOUND,
                   "Failed to find boot/vmlinuz-<CHECKSUM> in %s",
                   gs_file_get_path_cached (deployroot));
      goto out;
    }

  if (ret_initramfs != NULL)
    {
      if (strcmp (kernel_checksum, initramfs_checksum) != 0)
        {
          g_set_error (error, G_IO_ERROR, G_IO_ERROR_NOT_FOUND,
                       "Mismatched kernel %s checksum vs initrd %s",
                       gs_file_get_basename_cached (ret_initramfs),
                       gs_file_get_basename_cached (ret_initramfs));
          goto out;
        }
    }

  ot_transfer_out_value (out_kernel, &ret_kernel);
  ot_transfer_out_value (out_initramfs, &ret_initramfs);
  ret = TRUE;
 out:
  return ret;
}

static gboolean
checksum_from_kernel_src (GFile        *src,
                          char        **out_checksum,
                          GError     **error)
{
  const char *last_dash = strrchr (gs_file_get_path_cached (src), '-');
  if (!last_dash)
    {
      g_set_error (error, G_IO_ERROR, G_IO_ERROR_FAILED,
                   "Malformed initramfs name '%s', missing '-'", gs_file_get_basename_cached (src));
      return FALSE;
    }
  *out_checksum = g_strdup (last_dash + 1);
  return TRUE;
}

/* FIXME: We should really do individual fdatasync() on files/dirs,
 * since this causes us to block on unrelated I/O.  However, it's just
 * safer for now.
 */
static gboolean
full_system_sync (GCancellable      *cancellable,
                  GError           **error)
{
  sync ();
  return TRUE;
}

static gboolean
swap_bootlinks (OstreeSysroot *self,
                int            bootversion,
                GPtrArray    *new_deployments,
                GCancellable *cancellable,
                GError      **error)
{
  gboolean ret = FALSE;
  guint i;
  int old_subbootversion;
  int new_subbootversion;
  gs_unref_object GFile *ostree_dir = g_file_get_child (self->path, "ostree");
  gs_free char *ostree_bootdir_name = g_strdup_printf ("boot.%d", bootversion);
  gs_unref_object GFile *ostree_bootdir = g_file_resolve_relative_path (ostree_dir, ostree_bootdir_name);
  gs_free char *ostree_subbootdir_name = NULL;
  gs_unref_object GFile *ostree_subbootdir = NULL;

  if (bootversion != self->bootversion)
    {
      if (!_ostree_sysroot_read_current_subbootversion (self, bootversion, &old_subbootversion,
                                                        cancellable, error))
        goto out;
    }
  else
    old_subbootversion = self->subbootversion;

  new_subbootversion = old_subbootversion == 0 ? 1 : 0;

  ostree_subbootdir_name = g_strdup_printf ("boot.%d.%d", bootversion, new_subbootversion);
  ostree_subbootdir = g_file_resolve_relative_path (ostree_dir, ostree_subbootdir_name);

  if (!gs_file_ensure_directory (ostree_subbootdir, TRUE, cancellable, error))
    goto out;

  for (i = 0; i < new_deployments->len; i++)
    {
      OstreeDeployment *deployment = new_deployments->pdata[i];
      gs_free char *bootlink_pathname = g_strdup_printf ("%s/%s/%d",
                                                         ostree_deployment_get_osname (deployment),
                                                         ostree_deployment_get_bootcsum (deployment),
                                                         ostree_deployment_get_bootserial (deployment));
      gs_free char *bootlink_target = g_strdup_printf ("../../../deploy/%s/deploy/%s.%d",
                                                       ostree_deployment_get_osname (deployment),
                                                       ostree_deployment_get_csum (deployment),
                                                       ostree_deployment_get_deployserial (deployment));
      gs_unref_object GFile *linkname = g_file_get_child (ostree_subbootdir, bootlink_pathname);
      gs_unref_object GFile *linkname_parent = g_file_get_parent (linkname);

      if (!gs_file_ensure_directory (linkname_parent, TRUE, cancellable, error))
        goto out;

      if (!g_file_make_symbolic_link (linkname, bootlink_target, cancellable, error))
        goto out;
    }

  if (!ot_gfile_atomic_symlink_swap (ostree_bootdir, ostree_subbootdir_name,
                                     cancellable, error))
    goto out;

  ret = TRUE;
 out:
  return ret;
}

static char *
remove_checksum_from_kernel_name (const char *name,
                                  const char *csum)
{
  const char *p = strrchr (name, '-');
  g_assert_cmpstr (p+1, ==, csum);
  return g_strndup (name, p-name);
}

static GHashTable *
parse_os_release (const char *contents,
                  const char *split)
{
  char **lines = g_strsplit (contents, split, -1);
  char **iter;
  GHashTable *ret = g_hash_table_new_full (g_str_hash, g_str_equal, g_free, g_free);

  for (iter = lines; *iter; iter++)
    {
      char *line = *iter;
      char *eq;
      const char *quotedval;
      char *val;

      if (g_str_has_prefix (line, "#"))
        continue;
      
      eq = strchr (line, '=');
      if (!eq)
        continue;
      
      *eq = '\0';
      quotedval = eq + 1;
      val = g_shell_unquote (quotedval, NULL);
      if (!val)
        continue;
      
      g_hash_table_insert (ret, line, val);
    }

  return ret;
}

/*
 * install_deployment_kernel:
 * 
 * Write out an entry in /boot/loader/entries for @deployment.
 */
static gboolean
install_deployment_kernel (OstreeSysroot   *sysroot,
                           int             new_bootversion,
                           OstreeDeployment   *deployment,
                           guint           n_deployments,
                           GCancellable   *cancellable,
                           GError        **error)

{
  gboolean ret = FALSE;
  const char *osname = ostree_deployment_get_osname (deployment);
  const char *bootcsum = ostree_deployment_get_bootcsum (deployment);
  gs_unref_object GFile *bootdir = NULL;
  gs_unref_object GFile *bootcsumdir = NULL;
  gs_unref_object GFile *bootconfpath = NULL;
  gs_unref_object GFile *bootconfpath_parent = NULL;
  gs_free char *dest_kernel_name = NULL;
  gs_unref_object GFile *dest_kernel_path = NULL;
  gs_unref_object GFile *dest_initramfs_path = NULL;
  gs_unref_object GFile *tree_kernel_path = NULL;
  gs_unref_object GFile *tree_initramfs_path = NULL;
  gs_unref_object GFile *etc_os_release = NULL;
  gs_unref_object GFile *deployment_dir = NULL;
  gs_free char *contents = NULL;
  gs_unref_hashtable GHashTable *osrelease_values = NULL;
  gs_free char *linux_relpath = NULL;
  gs_free char *linux_key = NULL;
  gs_free char *initramfs_relpath = NULL;
  gs_free char *title_key = NULL;
  gs_free char *initrd_key = NULL;
  gs_free char *version_key = NULL;
  gs_free char *ostree_kernel_arg = NULL;
  gs_free char *options_key = NULL;
  __attribute__((cleanup(_ostree_ordered_hash_cleanup))) OstreeOrderedHash *ohash = NULL;
  const char *val;
  OstreeBootconfigParser *bootconfig;
  gsize len;

  bootconfig = ostree_deployment_get_bootconfig (deployment);
  deployment_dir = ostree_sysroot_get_deployment_directory (sysroot, deployment);

  if (!get_kernel_from_tree (deployment_dir, &tree_kernel_path, &tree_initramfs_path,
                             cancellable, error))
    goto out;

  bootdir = g_file_get_child (ostree_sysroot_get_path (sysroot), "boot");
  bootcsumdir = ot_gfile_resolve_path_printf (bootdir, "ostree/%s-%s",
                                              osname,
                                              bootcsum);
  bootconfpath = ot_gfile_resolve_path_printf (bootdir, "loader.%d/entries/ostree-%s-%d.conf",
                                               new_bootversion, osname, 
                                               ostree_deployment_get_index (deployment));

  if (!gs_file_ensure_directory (bootcsumdir, TRUE, cancellable, error))
    goto out;
  bootconfpath_parent = g_file_get_parent (bootconfpath);
  if (!gs_file_ensure_directory (bootconfpath_parent, TRUE, cancellable, error))
    goto out;

  dest_kernel_name = remove_checksum_from_kernel_name (gs_file_get_basename_cached (tree_kernel_path),
                                                       bootcsum);
  dest_kernel_path = g_file_get_child (bootcsumdir, dest_kernel_name);
  if (!g_file_query_exists (dest_kernel_path, NULL))
    {
      if (!gs_file_linkcopy_sync_data (tree_kernel_path, dest_kernel_path, G_FILE_COPY_OVERWRITE | G_FILE_COPY_NOFOLLOW_SYMLINKS | G_FILE_COPY_ALL_METADATA,
                                       cancellable, error))
        goto out;
    }

  if (tree_initramfs_path)
    {
      gs_free char *dest_initramfs_name = remove_checksum_from_kernel_name (gs_file_get_basename_cached (tree_initramfs_path),
                                                                       bootcsum);
      dest_initramfs_path = g_file_get_child (bootcsumdir, dest_initramfs_name);

      if (!g_file_query_exists (dest_initramfs_path, NULL))
        {
          if (!gs_file_linkcopy_sync_data (tree_initramfs_path, dest_initramfs_path, G_FILE_COPY_OVERWRITE | G_FILE_COPY_NOFOLLOW_SYMLINKS | G_FILE_COPY_ALL_METADATA,
                                           cancellable, error))
            goto out;
        }
    }

  etc_os_release = g_file_resolve_relative_path (deployment_dir, "etc/os-release");

  if (!g_file_load_contents (etc_os_release, cancellable,
                             &contents, &len, NULL, error))
    {
      g_prefix_error (error, "Reading /etc/os-release: ");
      goto out;
    }

  osrelease_values = parse_os_release (contents, "\n");

  /* title */
  val = g_hash_table_lookup (osrelease_values, "PRETTY_NAME");
  if (val == NULL)
      val = g_hash_table_lookup (osrelease_values, "ID");
  if (val == NULL)
    {
      g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_FAILED,
                           "No PRETTY_NAME or ID in /etc/os-release");
      goto out;
    }
  
  title_key = g_strdup_printf ("ostree:%s:%d %s", ostree_deployment_get_osname (deployment),
                               ostree_deployment_get_index (deployment),
                               val);
  ostree_bootconfig_parser_set (bootconfig, "title", title_key);

  version_key = g_strdup_printf ("%d", n_deployments - ostree_deployment_get_index (deployment));
  ostree_bootconfig_parser_set (bootconfig, "version", version_key);

  linux_relpath = g_file_get_relative_path (bootdir, dest_kernel_path);
  linux_key = g_strconcat ("/", linux_relpath, NULL);
  ostree_bootconfig_parser_set (bootconfig, "linux", linux_key);

  if (dest_initramfs_path)
    {
      initramfs_relpath = g_file_get_relative_path (bootdir, dest_initramfs_path);
      initrd_key = g_strconcat ("/", initramfs_relpath, NULL);
      ostree_bootconfig_parser_set (bootconfig, "initrd", initrd_key);
    }

  val = ostree_bootconfig_parser_get (bootconfig, "options");
  ostree_kernel_arg = g_strdup_printf ("/ostree/boot.%d/%s/%s/%d",
                                       new_bootversion, osname, bootcsum,
                                       ostree_deployment_get_bootserial (deployment));
  ohash = _ostree_sysroot_parse_kernel_args (val);
  _ostree_ordered_hash_replace_key (ohash, "ostree", ostree_kernel_arg);
  options_key = _ostree_sysroot_kernel_arg_string_serialize (ohash);
  ostree_bootconfig_parser_set (bootconfig, "options", options_key);
  
  if (!ostree_bootconfig_parser_write (ostree_deployment_get_bootconfig (deployment), bootconfpath,
                               cancellable, error))
      goto out;

  ret = TRUE;
 out:
  return ret;
}

static gboolean
swap_bootloader (OstreeSysroot  *sysroot,
                 int             current_bootversion,
                 int             new_bootversion,
                 GCancellable   *cancellable,
                 GError        **error)
{
  gboolean ret = FALSE;
  gs_unref_object GFile *boot_loader_link = NULL;
  gs_free char *new_target = NULL;

  g_assert ((current_bootversion == 0 && new_bootversion == 1) ||
            (current_bootversion == 1 && new_bootversion == 0));

  boot_loader_link = g_file_resolve_relative_path (sysroot->path, "boot/loader");
  new_target = g_strdup_printf ("loader.%d", new_bootversion);

  if (!ot_gfile_atomic_symlink_swap (boot_loader_link, new_target,
                                     cancellable, error))
    goto out;

  ret = TRUE;
 out:
  return ret;
}

static GHashTable *
bootcsum_counts_for_deployment_list (GPtrArray   *deployments,
                                     gboolean     set_bootserial)
{
  guint i;
  GHashTable *ret = 
    g_hash_table_new_full (g_str_hash, g_str_equal, NULL, NULL);

  for (i = 0; i < deployments->len; i++)
    {
      OstreeDeployment *deployment = deployments->pdata[i];
      const char *bootcsum = ostree_deployment_get_bootcsum (deployment);
      guint count;

      count = GPOINTER_TO_UINT (g_hash_table_lookup (ret, bootcsum));
      g_hash_table_replace (ret, (char*)bootcsum, GUINT_TO_POINTER (count + 1));

      if (set_bootserial)
        ostree_deployment_set_bootserial (deployment, count);
    }
  return ret;
}

/* TEMPORARY HACK: Add a "current" symbolic link that's easy to
 * follow inside the gnome-ostree build scripts.  This isn't atomic,
 * but that doesn't matter because it's only used by deployments
 * done from the host.
 */
static gboolean
create_current_symlinks (OstreeSysroot         *self,
                         GCancellable          *cancellable,
                         GError               **error)
{
  gboolean ret = FALSE;
  guint i;
  gs_unref_hashtable GHashTable *created_current_for_osname =
    g_hash_table_new (g_str_hash, g_str_equal);

  for (i = 0; i < self->deployments->len; i++)
    {
      OstreeDeployment *deployment = self->deployments->pdata[i];
      const char *osname = ostree_deployment_get_osname (deployment);

      if (!g_hash_table_lookup (created_current_for_osname, osname))
        {
          gs_unref_object GFile *osdir = ot_gfile_resolve_path_printf (self->path, "ostree/deploy/%s", osname);
          gs_unref_object GFile *os_current_path = g_file_get_child (osdir, "current");
          gs_unref_object GFile *deployment_path = ostree_sysroot_get_deployment_directory (self, deployment);
          gs_free char *target = g_file_get_relative_path (osdir, deployment_path);
          
          g_assert (target != NULL);
          
          if (!ot_gfile_atomic_symlink_swap (os_current_path, target,
                                             cancellable, error))
            goto out;

          g_hash_table_insert (created_current_for_osname, (char*)osname, GUINT_TO_POINTER (1));
        }
    }

  ret = TRUE;
 out:
  return ret;
}

/**
 * ostree_sysroot_write_deployments:
 * @self: Sysroot
 * @new_deployments: (element-type OstreeDeployment): List of new deployments
 * @cancellable: Cancellable
 * @error: Error
 *
 * Assuming @new_deployments have already been deployed in place on
 * disk, atomically update bootloader configuration.
 */
gboolean
ostree_sysroot_write_deployments (OstreeSysroot     *self,
                                  GPtrArray         *new_deployments,
                                  GCancellable      *cancellable,
                                  GError           **error)
{
  gboolean ret = FALSE;
  guint i;
  gboolean requires_new_bootversion = FALSE;
  gboolean found_booted_deployment = FALSE;
  gs_unref_hashtable GHashTable *new_bootcsum_to_count = NULL;

  g_assert (self->loaded);

  /* Calculate the total number of deployments per bootcsums; while we
   * are doing this, assign a bootserial to each new deployment.
   */
  new_bootcsum_to_count = bootcsum_counts_for_deployment_list (new_deployments, TRUE);

  /* Determine whether or not we need to touch the bootloader
   * configuration.  If we have an equal number of deployments and
   * more strongly an equal number of deployments per bootcsum, then
   * we can just swap the subbootversion bootlinks.
   */
  if (new_deployments->len != self->deployments->len)
    requires_new_bootversion = TRUE;
  else
    {
      GHashTableIter hashiter;
      gpointer hkey, hvalue;
      gs_unref_hashtable GHashTable *orig_bootcsum_to_count
        = bootcsum_counts_for_deployment_list (self->deployments, FALSE);

      g_hash_table_iter_init (&hashiter, orig_bootcsum_to_count);
      while (g_hash_table_iter_next (&hashiter, &hkey, &hvalue))
        {
          guint orig_count = GPOINTER_TO_UINT (hvalue);
          gpointer new_countp = g_hash_table_lookup (new_bootcsum_to_count, hkey);
          guint new_count = GPOINTER_TO_UINT (new_countp);

          if (orig_count != new_count)
            {
              requires_new_bootversion = TRUE;
              break;
            }
        }
    }

  for (i = 0; i < new_deployments->len; i++)
    {
      OstreeDeployment *deployment = new_deployments->pdata[i];
      
      if (deployment == self->booted_deployment)
        found_booted_deployment = TRUE;

      ostree_deployment_set_index (deployment, i);
    }

  if (self->booted_deployment && !found_booted_deployment)
    {
      g_set_error (error, G_IO_ERROR, G_IO_ERROR_FAILED, "Attempting to remove booted deployment");
      goto out;
    }

  if (!requires_new_bootversion)
    {
      if (!full_system_sync (cancellable, error))
        {
          g_prefix_error (error, "Full sync: ");
          goto out;
        }

      if (!swap_bootlinks (self, self->bootversion,
                           new_deployments,
                           cancellable, error))
        {
          g_prefix_error (error, "Swapping current bootlinks: ");
          goto out;
        }
    }
  else
    {
      int new_bootversion = self->bootversion ? 0 : 1;
      gs_unref_object OstreeBootloader *bootloader = _ostree_sysroot_query_bootloader (self);
      gs_unref_object GFile *new_loader_entries_dir = NULL;

      if (bootloader)
        g_print ("Detected bootloader: %s\n", _ostree_bootloader_get_name (bootloader));
      else
        g_print ("Detected bootloader: (unknown)\n");

      new_loader_entries_dir = ot_gfile_resolve_path_printf (self->path, "boot/loader.%d/entries",
                                                             new_bootversion);
      if (!gs_file_ensure_directory (new_loader_entries_dir, TRUE, cancellable, error))
        goto out;
      
      for (i = 0; i < new_deployments->len; i++)
        {
          OstreeDeployment *deployment = new_deployments->pdata[i];
          if (!install_deployment_kernel (self, new_bootversion,
                                          deployment, new_deployments->len,
                                          cancellable, error))
            {
              g_prefix_error (error, "Installing kernel: ");
              goto out;
            }
        }

      /* Swap bootlinks for *new* version */
      if (!swap_bootlinks (self, new_bootversion, new_deployments,
                           cancellable, error))
        {
          g_prefix_error (error, "Generating new bootlinks: ");
          goto out;
        }

      if (bootloader && !_ostree_bootloader_write_config (bootloader, new_bootversion,
                                                          cancellable, error))
        {
          g_prefix_error (error, "Bootloader write config: ");
          goto out;
        }

      if (!full_system_sync (cancellable, error))
        {
          g_prefix_error (error, "Full sync: ");
          goto out;
        }

      if (!swap_bootloader (self, self->bootversion, new_bootversion,
                            cancellable, error))
        {
          g_prefix_error (error, "Final bootloader swap: ");
          goto out;
        }
    }

  g_print ("Transaction complete, performing cleanup\n");

  /* Now reload from disk */
  if (!ostree_sysroot_load (self, cancellable, error))
    {
      g_prefix_error (error, "Reloading deployments after commit: ");
      goto out;
    }

  if (!create_current_symlinks (self, cancellable, error))
    goto out;

  /* And finally, cleanup of any leftover data.
   */
  if (!ostree_sysroot_cleanup (self, cancellable, error))
    {
      g_prefix_error (error, "Performing final cleanup: ");
      goto out;
    }

  ret = TRUE;
 out:
  return ret;
}

static gboolean
allocate_deployserial (OstreeSysroot           *self,
                       const char              *osname,
                       const char              *revision,
                       int                     *out_deployserial,
                       GCancellable            *cancellable,
                       GError                 **error)
{
  gboolean ret = FALSE;
  guint i;
  int new_deployserial = 0;
  gs_unref_object GFile *osdir = NULL;
  gs_unref_ptrarray GPtrArray *tmp_current_deployments =
    g_ptr_array_new_with_free_func (g_object_unref);

  osdir = ot_gfile_get_child_build_path (self->path, "ostree/deploy", osname, NULL);
  
  if (!_ostree_sysroot_list_deployment_dirs_for_os (osdir, tmp_current_deployments,
                                                    cancellable, error))
    goto out;

  for (i = 0; i < tmp_current_deployments->len; i++)
    {
      OstreeDeployment *deployment = tmp_current_deployments->pdata[i];
      
      if (strcmp (ostree_deployment_get_osname (deployment), osname) != 0)
        continue;
      if (strcmp (ostree_deployment_get_csum (deployment), revision) != 0)
        continue;

      new_deployserial = MAX(new_deployserial, ostree_deployment_get_deployserial (deployment)+1);
    }

  ret = TRUE;
  *out_deployserial = new_deployserial;
 out:
  return ret;
}
                            
/**
 * ostree_sysroot_deploy_one_tree:
 * @self: Sysroot
 * @osname: (allow-none): osname to use for merge deployment
 * @revision: Checksum to add
 * @origin: (allow-none): Origin to use for upgrades
 * @add_kernel_argv: (allow-none): Append these arguments to kernel configuration
 * @provided_merge_deployment: (allow-none): Use this deployment for merge path
 * @out_new_deployment: (out): The new deployment path
 * @cancellable: Cancellable
 * @error: Error
 *
 * Check out deployment tree with revision @revision, performing a 3
 * way merge with @provided_merge_deployment for configuration.
 */
gboolean
ostree_sysroot_deploy_one_tree (OstreeSysroot     *self,
                                const char        *osname,
                                const char        *revision,
                                GKeyFile          *origin,
                                char             **add_kernel_argv,
                                OstreeDeployment  *provided_merge_deployment,
                                OstreeDeployment **out_new_deployment,
                                GCancellable      *cancellable,
                                GError           **error)
{
  gboolean ret = FALSE;
  gint new_deployserial;
  gs_unref_object OstreeDeployment *new_deployment = NULL;
  gs_unref_object OstreeDeployment *merge_deployment = NULL;
  gs_unref_object OstreeRepo *repo = NULL;
  gs_unref_object GFile *commit_root = NULL;
  gs_unref_object GFile *tree_kernel_path = NULL;
  gs_unref_object GFile *tree_initramfs_path = NULL;
  gs_unref_object GFile *new_deployment_path = NULL;
  gs_free char *new_bootcsum = NULL;
  gs_unref_object OstreeBootconfigParser *bootconfig = NULL;

  g_return_val_if_fail (osname != NULL || self->booted_deployment != NULL, FALSE);

  if (osname == NULL)
    osname = ostree_deployment_get_osname (self->booted_deployment);

  if (!ostree_sysroot_get_repo (self, &repo, cancellable, error))
    goto out;

  if (!ostree_repo_read_commit (repo, revision, &commit_root, NULL, cancellable, error))
    goto out;

  if (!get_kernel_from_tree (commit_root, &tree_kernel_path, &tree_initramfs_path,
                             cancellable, error))
    goto out;
  
  if (tree_initramfs_path != NULL)
    {
      if (!checksum_from_kernel_src (tree_initramfs_path, &new_bootcsum, error))
        goto out;
    }
  else
    {
      if (!checksum_from_kernel_src (tree_kernel_path, &new_bootcsum, error))
        goto out;
    }

  if (provided_merge_deployment != NULL)
    merge_deployment = g_object_ref (provided_merge_deployment);

  if (!allocate_deployserial (self, osname, revision, &new_deployserial,
                              cancellable, error))
    goto out;

  new_deployment = ostree_deployment_new (0, osname, revision, new_deployserial,
                                          new_bootcsum, -1);
  ostree_deployment_set_origin (new_deployment, origin);

  /* Check out the userspace tree onto the filesystem */
  if (!checkout_deployment_tree (self, repo, new_deployment, &new_deployment_path,
                                 cancellable, error))
    {
      g_prefix_error (error, "Checking out tree: ");
      goto out;
    }

  if (!write_origin_file (self, new_deployment, cancellable, error))
    {
      g_prefix_error (error, "Writing out origin file: ");
      goto out;
    }

  /* Create an empty boot configuration; we will merge things into
   * it as we go.
   */
  bootconfig = ostree_bootconfig_parser_new ();
  ostree_deployment_set_bootconfig (new_deployment, bootconfig);

  if (!merge_configuration (self, merge_deployment, new_deployment,
                            new_deployment_path,
                            cancellable, error))
    {
      g_prefix_error (error, "During /etc merge: ");
      goto out;
    }

  /* We have inherited kernel arguments from the previous deployment;
   * now, override/extend that with arguments provided by the command
   * line.
   * 
   * After this, install_deployment_kernel() will set the other boot
   * options and write it out to disk.
   */
  if (add_kernel_argv)
    {
      char **strviter;
      __attribute__((cleanup(_ostree_ordered_hash_cleanup))) OstreeOrderedHash *ohash = NULL;
      gs_free char *new_options = NULL;

      ohash = _ostree_sysroot_parse_kernel_args (ostree_bootconfig_parser_get (bootconfig, "options"));

      for (strviter = add_kernel_argv; *strviter; strviter++)
        {
          char *karg = g_strdup (*strviter);
          const char *val = _ostree_sysroot_split_keyeq (karg);
        
          _ostree_ordered_hash_replace_key_take (ohash, karg, val);
        }

      new_options = _ostree_sysroot_kernel_arg_string_serialize (ohash);
      ostree_bootconfig_parser_set (bootconfig, "options", new_options);
    }

  ret = TRUE;
  ot_transfer_out_value (out_new_deployment, &new_deployment);
 out:
  return ret;
}