repository: add a copy_to method

This will create a repository in a different path, so it does not
appear until the copy is complete.

1 files changed, 51 insertions, 0 deletions

diff --git a/lib/gitano/repository.lua b/lib/gitano/repository.lua
index e6f4fee..36f9579 100644
--- a/lib/gitano/repository.lua
+++ b/lib/gitano/repository.lua
@@ -507,6 +507,57 @@ function repo_method:rename_to(somename)
    return true
 end
 
+function repo_method:copy_to(target)
+   local ok, err
+
+   if not target.is_nascent then
+      return false, "Target repository is not Nascent"
+   end
+
+   local newpath = target:fs_path()
+   -- copy to a different path so it does not appear until finished
+   local temp_path = newpath .. ".in_progress"
+
+   if not util.mkdir_p(util.dirname(temp_path)) then
+      return false, "Cannot prepare path leading to repository."
+   end
+
+   local from = self:fs_path()
+   local function filter(parent, name, info)
+      return parent == from and name == "objects"
+             or util.copy_dir_filter_base(parent, name, info)
+   end
+   -- copy non-objects parts of the git repository
+   ok, err = util.copy_dir(from, temp_path, nil, filter)
+   if not ok then
+      log.error("Failed to copy repository", from, "to", temp_path, err)
+      util.rm_rf(temp_path)
+      return false, "Failed to copy repository"
+   end
+   -- Hardlink the objects tree
+   local cbs = util.deep_copy(util.copy_dir_copy_callbacks)
+   cbs[luxio.DT_REG] = util.hardlink_file
+   ok, err = util.copy_dir(util.path_join(from, 'objects'),
+                           util.path_join(temp_path, 'objects'),
+                           cbs)
+   if not ok then
+      log.error("Failed to hardlink objects of", from, "to", temp_path, err)
+      util.rm_rf(temp_path)
+      return ok, "Failed to copy repository"
+   end
+
+   -- rename into place
+   ok, err = luxio.rename(temp_path, newpath)
+   if ok ~= 0 then
+      log.error("Failed to rename repository", temp_path, "to",
+                newpath, luxio.strerror(err))
+      util.rm_rf(temp_path)
+      return false, "Failed to copy repository"
+   end
+
+   return true
+end
+
 function repo_method:update_modified_date(shas)
    -- Update the info/web/last-modified
    local dirpath = self:fs_path() .. "/info/web"