do_for_each_entry(): increment the packed refs cache refcount

This function calls a user-supplied callback function which could do
something that causes the packed refs cache to be invalidated.  So
acquire a reference count on the data structure to prevent our copy
from being freed while we are iterating over it.

Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/refs.c b/refs.c
index 80c172f..f33d224 100644 (file)
--- a/refs.c
+++ b/refs.c
@@ -1590,10 +1590,12 @@ void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname)
 static int do_for_each_entry(struct ref_cache *refs, const char *base,
                             each_ref_entry_fn fn, void *cb_data)
 {
-       struct ref_dir *packed_dir = get_packed_refs(refs);
+       struct packed_ref_cache *packed_ref_cache = get_packed_ref_cache(refs);
+       struct ref_dir *packed_dir = get_packed_ref_dir(packed_ref_cache);
        struct ref_dir *loose_dir = get_loose_refs(refs);
        int retval = 0;
 
+       acquire_packed_ref_cache(packed_ref_cache);
        if (base && *base) {
                packed_dir = find_containing_dir(packed_dir, base, 0);
                loose_dir = find_containing_dir(loose_dir, base, 0);
@@ -1614,6 +1616,7 @@ static int do_for_each_entry(struct ref_cache *refs, const char *base,
                                loose_dir, 0, fn, cb_data);
        }
 
+       release_packed_ref_cache(packed_ref_cache);
        return retval;
 }