repo: Move the 'init' builtin command to a public API, ostree_repo_create

This continues the goal of making more of ostree accessible by API,
rather than forking out to subprocesses.

https://bugzilla.gnome.org/show_bug.cgi?id=707582

src/libostree/ostree-repo.c

@@ -52,6 +52,12 @@
  * content files zlib-compressed.  It is suitable for non-root-owned
  * repositories that can be served via a static HTTP server.
  *
+ * Creating an #OstreeRepo does not invoke any file I/O, and thus needs
+ * to be initialized, either from an existing contents or with a new
+ * repository. If you have an existing repo, use ostree_repo_check()
+ * to load it from disk and check its validity. To initialize a new
+ * repository in the given filepath, use ostree_repo_create() instead.
+ *
  * To store content in the repo, first start a transaction with
  * ostree_repo_prepare_transaction().  Then create a
  * #OstreeMutableTree, and apply functions such as
@@ -311,6 +317,34 @@ ostree_repo_write_config (OstreeRepo *self,
   return ret;
 }
 
+static gboolean
+ostree_repo_mode_to_string (OstreeRepoMode   mode,
+                            const char     **out_mode,
+                            GError         **error)
+{
+  gboolean ret = FALSE;
+  const char *ret_mode;
+
+  switch (mode)
+    {
+    case OSTREE_REPO_MODE_BARE:
+      ret_mode = "bare";
+      break;
+    case OSTREE_REPO_MODE_ARCHIVE_Z2:
+      ret_mode ="archive-z2";
+      break;
+    default:
+      g_set_error (error, G_IO_ERROR, G_IO_ERROR_FAILED,
+                   "Invalid mode '%d'", mode);
+      goto out;
+    }
+
+  ret = TRUE;
+  *out_mode = ret_mode;
+ out:
+  return ret;
+}
+
 gboolean
 ostree_repo_mode_from_string (const char      *mode,
                               OstreeRepoMode  *out_mode,
@@ -336,6 +370,81 @@ ostree_repo_mode_from_string (const char      *mode,
   return ret;
 }
 
+#define DEFAULT_CONFIG_CONTENTS ("[core]\n" \
+                                 "repo_version=1\n")
+
+/**
+ * ostree_repo_create:
+ * @self: An #OstreeRepo
+ * @mode: The mode to store the repository in
+ * @cancellable: Cancellable
+ * @error: Error
+ *
+ * Create the underlying structure on disk for the
+ * repository.
+ */
+gboolean
+ostree_repo_create (OstreeRepo     *self,
+                    OstreeRepoMode  mode,
+                    GCancellable   *cancellable,
+                    GError        **error)
+{
+  gboolean ret = FALSE;
+  GString *config_data = NULL;
+  gs_unref_object GFile *child = NULL;
+  gs_unref_object GFile *grandchild = NULL;
+  const char *mode_str;
+
+  if (!ostree_repo_mode_to_string (mode, &mode_str, error))
+    goto out;
+
+  if (!gs_file_ensure_directory (self->repodir, FALSE, cancellable, error))
+    goto out;
+
+  config_data = g_string_new (DEFAULT_CONFIG_CONTENTS);
+  g_string_append_printf (config_data, "mode=%s\n", mode_str);
+  if (!g_file_replace_contents (self->config_file,
+                                config_data->str,
+                                config_data->len,
+                                NULL, FALSE, 0, NULL,
+                                cancellable, error))
+    goto out;
+
+  if (!g_file_make_directory (self->objects_dir, cancellable, error))
+    goto out;
+
+  if (!g_file_make_directory (self->tmp_dir, cancellable, error))
+    goto out;
+
+  if (!g_file_make_directory (self->remote_cache_dir, cancellable, error))
+    goto out;
+
+  g_clear_object (&child);
+  child = g_file_get_child (self->repodir, "refs");
+  if (!g_file_make_directory (child, cancellable, error))
+    goto out;
+
+  g_clear_object (&grandchild);
+  grandchild = g_file_get_child (child, "heads");
+  if (!g_file_make_directory (grandchild, cancellable, error))
+    goto out;
+
+  g_clear_object (&grandchild);
+  grandchild = g_file_get_child (child, "remotes");
+  if (!g_file_make_directory (grandchild, cancellable, error))
+    goto out;
+
+  if (!ostree_repo_check (self, error))
+    goto out;
+
+  ret = TRUE;
+
+ out:
+  if (config_data)
+    g_string_free (config_data, TRUE);
+  return ret;
+}
+
 gboolean
 ostree_repo_check (OstreeRepo *self, GError **error)
 {

src/libostree/ostree-repo.h

@@ -33,16 +33,6 @@ G_BEGIN_DECLS
 #define OSTREE_IS_REPO(obj) \
   (G_TYPE_CHECK_INSTANCE_TYPE ((obj), OSTREE_TYPE_REPO))
 
-GType ostree_repo_get_type (void);
-
-OstreeRepo* ostree_repo_new (GFile *path);
-
-OstreeRepo* ostree_repo_new_default (void);
-
-gboolean      ostree_repo_check (OstreeRepo  *self, GError **error);
-
-GFile *       ostree_repo_get_path (OstreeRepo  *self);
-
 /**
  * OstreeRepoMode:
  * @OSTREE_REPO_MODE_BARE: Files are stored as themselves; can only be written as root
@@ -56,9 +46,24 @@ typedef enum {
   OSTREE_REPO_MODE_ARCHIVE_Z2
 } OstreeRepoMode;
 
-gboolean       ostree_repo_mode_from_string (const char      *mode,
-                                             OstreeRepoMode  *out_mode,
-                                             GError         **error);
+gboolean ostree_repo_mode_from_string (const char      *mode,
+                                       OstreeRepoMode  *out_mode,
+                                       GError         **error);
+
+GType ostree_repo_get_type (void);
+
+OstreeRepo* ostree_repo_new (GFile *path);
+
+OstreeRepo* ostree_repo_new_default (void);
+
+gboolean      ostree_repo_check (OstreeRepo  *self, GError **error);
+
+gboolean      ostree_repo_create (OstreeRepo     *self,
+                                  OstreeRepoMode  mode,
+                                  GCancellable   *cancellable,
+                                  GError        **error);
+
+GFile *       ostree_repo_get_path (OstreeRepo  *self);
 
 OstreeRepoMode ostree_repo_get_mode (OstreeRepo  *self);