midx: Add a way to write multi-pack-index files

This change adds the git_midx_writer_* functions to allow to
write and create `multi-pack-index` files from `.idx`/`.pack` files.

Part of: #5399

1 files changed, 16 insertions, 0 deletions

diff --git a/src/pack.h b/src/pack.h
index 1d077240d..8aea7d8f9 100644
--- a/src/pack.h
+++ b/src/pack.h
@@ -20,6 +20,14 @@
 #include "oidmap.h"
 #include "zstream.h"
 
+/**
+ * Function type for callbacks from git_pack_foreach_entry_offset.
+ */
+typedef int GIT_CALLBACK(git_pack_foreach_entry_offset_cb)(
+		const git_oid *id,
+		off64_t offset,
+		void *payload);
+
 #define GIT_PACK_FILE_MODE 0444
 
 #define PACK_SIGNATURE 0x5041434b	/* "PACK" */
@@ -176,5 +184,13 @@ int git_pack_foreach_entry(
 		struct git_pack_file *p,
 		git_odb_foreach_cb cb,
 		void *data);
+/**
+ * Similar to git_pack_foreach_entry, but it also provides the offset of the
+ * object within the packfile. It also does not sort the objects in any order.
+ */
+int git_pack_foreach_entry_offset(
+		struct git_pack_file *p,
+		git_pack_foreach_entry_offset_cb cb,
+		void *data);
 
 #endif