3 files changed, 52 insertions, 1 deletions
diff --git a/git.go b/git.go
index fdc640a..bc97064 100644
--- a/git.go
+++ b/git.go
@@ -96,6 +96,26 @@ func (oid *Oid) NCmp(oid2 *Oid, n uint) int {
 	return bytes.Compare(oid.bytes[:n], oid2.bytes[:n])
 }
 
+func ShortenOids(ids []*Oid, minlen int) (int, error) {
+	shorten := C.git_oid_shorten_new(C.size_t(minlen))
+	if shorten == nil {
+		panic("Out of memory")
+	}
+	defer C.git_oid_shorten_free(shorten)
+
+	var ret C.int
+	for _, id := range ids {
+		buf := make([]byte, 41)
+		C.git_oid_fmt((*C.char)(unsafe.Pointer(&buf[0])), id.toC())
+		buf[40] = 0
+		ret = C.git_oid_shorten_add(shorten, (*C.char)(unsafe.Pointer(&buf[0])))
+		if ret < 0 {
+			return int(ret), LastError()
+		}
+	}
+	return int(ret), nil
+}
+
 type GitError struct {
 	Message string
 	Code int
diff --git a/odb.go b/odb.go
index bf17171..f6eb591 100644
--- a/odb.go
+++ b/odb.go
@@ -4,6 +4,8 @@ package git
 #cgo pkg-config: libgit2
 #include <git2.h>
 #include <git2/errors.h>
+
+extern int _go_git_odb_foreach(git_odb *db, void *payload);
 */
 import "C"
 import (
@@ -53,6 +55,32 @@ func (v *Odb) Read(oid *Oid) (obj *OdbObject, err error) {
 	return
 }
 
+//export odbForEachCb
+func odbForEachCb(id *C.git_oid, payload unsafe.Pointer) int {
+	ch := *(*chan *Oid)(payload)
+	oid := newOidFromC(id)
+	// Because the channel is unbuffered, we never read our own data. If ch is
+	// readable, the user has sent something on it, which means we should
+	// abort.
+	select {
+	case ch <- oid:
+	case <-ch:
+			return -1
+	}
+	return 0;
+}
+
+func (v *Odb) forEachWrap(ch chan *Oid) {
+	C._go_git_odb_foreach(v.ptr, unsafe.Pointer(&ch))
+	close(ch)
+}
+
+func (v *Odb) ForEach() chan *Oid {
+	ch := make(chan *Oid, 0)
+	go v.forEachWrap(ch)
+	return ch
+}
+
 type OdbObject struct {
 	ptr *C.git_odb_object
 }
@@ -83,4 +111,3 @@ func (object *OdbObject) Data() (data []byte) {
 
 	return blob
 }
-
diff --git a/wrapper.c b/wrapper.c
index 67f34fd..2af3974 100644
--- a/wrapper.c
+++ b/wrapper.c
@@ -20,4 +20,8 @@ int _go_git_packbuilder_foreach(git_packbuilder *pb, void *payload)
     return git_packbuilder_foreach(pb, (git_packbuilder_foreach_cb)&packbuilderForEachCb, payload);
 }
 
+int _go_git_odb_foreach(git_odb *db, void *payload)
+{
+    return git_odb_foreach(db, (git_odb_foreach_cb)&odbForEachCb, payload);
+}
 /* EOF */