Add support for custom backends

Signed-off-by: Matthaus Woolard <matthaus.woolard@gmail.com>

pygit2/repository.py

@@ -40,7 +40,7 @@ else:
 import six
 
 # Import from pygit2
-from _pygit2 import Repository as _Repository
+from _pygit2 import Repository as _Repository, init_file_backend
 from _pygit2 import Oid, GIT_OID_HEXSZ, GIT_OID_MINPREFIXLEN
 from _pygit2 import GIT_CHECKOUT_SAFE, GIT_CHECKOUT_RECREATE_MISSING, GIT_DIFF_NORMAL
 from _pygit2 import GIT_FILEMODE_LINK
@@ -56,23 +56,12 @@ from .utils import to_bytes, is_string
 from .submodule import Submodule
 
 
-class Repository(_Repository):
+class BaseRepository(_Repository):
 
-    def __init__(self, path, *args, **kwargs):
-        if not isinstance(path, six.string_types):
-            path = path.decode('utf-8')
-        super(Repository, self).__init__(path, *args, **kwargs)
+    def __init__(self, backend, *args, **kwargs):
+        super(BaseRepository, self).__init__(backend, *args, **kwargs)
         self._common_init()
 
-    @classmethod
-    def _from_c(cls, ptr, owned):
-        cptr = ffi.new('git_repository **')
-        cptr[0] = ptr
-        repo = cls.__new__(cls)
-        super(cls, repo)._from_c(bytes(ffi.buffer(cptr)[:]), owned)
-        repo._common_init()
-        return repo
-
     def _common_init(self):
         self.remotes = RemoteCollection(self)
 
@@ -915,3 +904,21 @@ class Repository(_Repository):
 
         err = C.git_repository_set_ident(self._repo, to_bytes(name), to_bytes(email))
         check_error(err)
+
+
+class Repository(BaseRepository):
+    def __init__(self, path, *args, **kwargs):
+        if not isinstance(path, six.string_types):
+            path = path.decode('utf-8')
+
+        path_backend = init_file_backend(path)
+        super(Repository, self).__init__(backend=path_backend, *args, **kwargs)
+
+    @classmethod
+    def _from_c(cls, ptr, owned):
+        cptr = ffi.new('git_repository **')
+        cptr[0] = ptr
+        repo = cls.__new__(cls)
+        super(cls, repo)._from_c(bytes(ffi.buffer(cptr)[:]), owned)
+        repo._common_init()
+        return repo

src/pygit2.c

@@ -144,7 +144,43 @@ hash(PyObject *self, PyObject *args)
 }
 
 
+PyDoc_STRVAR(init_file_backend__doc__,
+  "init_file_backend(path) -> object\n"
+  "\n"
+  "open repo backend given path.");
+PyObject *
+init_file_backend(PyObject *self, PyObject *args)
+{
+    const char* path;
+    int err = GIT_OK;
+    git_repository *repository = NULL;
+    if (!PyArg_ParseTuple(args, "s", &path)) {
+        return NULL;
+    };
+
+    err = git_repository_open(&repository, path);
+
+    if (err < 0) {
+        Error_set_str(err, path);
+        err = -1;
+        goto cleanup;
+    }
+
+    return PyCapsule_New(repository, "backend", NULL);
+
+cleanup:
+  if (repository)
+    git_repository_free(repository);
+
+  PyErr_Format(PyExc_Exception,
+          "Git error %d during construction of git repo", err);
+  return NULL;
+}
+
+
 PyMethodDef module_methods[] = {
+    {"init_file_backend", init_file_backend, METH_VARARGS,
+    init_file_backend__doc__},
     {"discover_repository", discover_repository, METH_VARARGS,
      discover_repository__doc__},
     {"hashfile", hashfile, METH_VARARGS, hashfile__doc__},

src/repository.c

@@ -88,7 +88,7 @@ wrap_repository(git_repository *c_repo)
 int
 Repository_init(Repository *self, PyObject *args, PyObject *kwds)
 {
-    char *path;
+    PyObject *backend;
     int err;
 
     if (kwds && PyDict_Size(kwds) > 0) {
@@ -97,15 +97,16 @@ Repository_init(Repository *self, PyObject *args, PyObject *kwds)
         return -1;
     }
 
-    if (!PyArg_ParseTuple(args, "s", &path))
-        return -1;
-
-    err = git_repository_open(&self->repo, path);
-    if (err < 0) {
-        Error_set_str(err, path);
-        return -1;
+    if (!PyArg_ParseTuple(args, "O", &backend)) {
+    	return -1;
     }
 
+    self->repo = PyCapsule_GetPointer(backend, "backend");
+	if (self->repo == NULL) {
+		PyErr_SetString(PyExc_TypeError,
+                        "Repository unable to unpack backend.");
+        return -1;
+	}
     self->owned = 1;
     self->config = NULL;
     self->index = NULL;
@@ -1747,7 +1748,7 @@ PyGetSetDef Repository_getseters[] = {
 
 
 PyDoc_STRVAR(Repository__doc__,
-  "Repository(path) -> Repository\n"
+  "Repository(backend) -> Repository\n"
   "\n"
   "Git repository.");
 
@@ -1793,3 +1794,4 @@ PyTypeObject RepositoryType = {
     0,                                         /* tp_alloc          */
     0,                                         /* tp_new            */
 };
+