[PATCH 23/23] midx: clear midx on repack

[Derrick Stolee]

If a 'git repack' command replaces existing packfiles, then we must
clear the existing multi-pack-index before moving the packfiles it
references.

Signed-off-by: Derrick Stolee <dsto...@microsoft.com>
---
 builtin/repack.c | 8 ++++++++
 midx.c           | 8 ++++++++
 midx.h           | 1 +
 3 files changed, 17 insertions(+)

diff --git a/builtin/repack.c b/builtin/repack.c
index 6c636e159e..66a7d8e8ea 100644
--- a/builtin/repack.c
+++ b/builtin/repack.c
@@ -8,6 +8,7 @@
 #include "strbuf.h"
 #include "string-list.h"
 #include "argv-array.h"
+#include "midx.h"
 
 static int delta_base_offset = 1;
 static int pack_kept_objects = -1;
@@ -174,6 +175,7 @@ int cmd_repack(int argc, const char **argv, const char 
*prefix)
        int no_update_server_info = 0;
        int quiet = 0;
        int local = 0;
+       int midx_cleared = 0;
 
        struct option builtin_repack_options[] = {
                OPT_BIT('a', NULL, &pack_everything,
@@ -340,6 +342,12 @@ int cmd_repack(int argc, const char **argv, const char 
*prefix)
                                continue;
                        }
 
+                       if (!midx_cleared) {
+                               /* if we move a packfile, it will invalidated 
the midx */
+                               clear_midx_file(get_object_directory());
+                               midx_cleared = 1;
+                       }
+
                        fname_old = mkpathdup("%s/old-%s%s", packdir,
                                                item->string, exts[ext].name);
                        if (file_exists(fname_old))
diff --git a/midx.c b/midx.c
index e46f392fa4..1043c01fa7 100644
--- a/midx.c
+++ b/midx.c
@@ -913,3 +913,11 @@ int write_midx_file(const char *object_dir)
        FREE_AND_NULL(pack_names);
        return 0;
 }
+
+void clear_midx_file(const char *object_dir)
+{
+       char *midx = get_midx_filename(object_dir);
+
+       if (remove_path(midx))
+               die(_("failed to clear multi-pack-index at %s"), midx);
+}
diff --git a/midx.h b/midx.h
index 6996b5ff6b..46f9f44c94 100644
--- a/midx.h
+++ b/midx.h
@@ -18,5 +18,6 @@ int midx_contains_pack(struct midxed_git *m, const char 
*idx_name);
 int prepare_midxed_git_one(struct repository *r, const char *object_dir);
 
 int write_midx_file(const char *object_dir);
+void clear_midx_file(const char *object_dir);
 
 #endif
-- 
2.18.0.rc1