Merge branch 'nd/find-pack-entry-recent-cache-invalidation'

* nd/find-pack-entry-recent-cache-invalidation:
find_pack_entry(): do not keep packed_git pointer locally
sha1_file.c: move the core logic of find_pack_entry() into fill_pack_entry()

diff --combined sha1_file.c
index d9aa0e0a2cd45acbbe3beb6c015f5f9071a22902,6b1b5125c8f992927b70ce10c43f2332f5948bc0..f9f8d5e91c278000e5869f49ba6a79ddfaf13145
--- 1/sha1_file.c
--- 2/sha1_file.c
+++ b/sha1_file.c
@@@ -54,6 -54,8 +54,8 @@@ static struct cached_object empty_tree 
        0
  };
  
+ static struct packed_git *last_found_pack;
+ 
  static struct cached_object *find_cached_object(const unsigned char *sha1)
  {
        int i;
@@@ -720,6 -722,8 +722,8 @@@ void free_pack_by_name(const char *pack
                        close_pack_index(p);
                        free(p->bad_object_sha1);
                        *pp = p->next;
+                       if (last_found_pack == p)
+                               last_found_pack = NULL;
                        free(p);
                        return;
                }
@@@ -1202,11 -1206,6 +1206,11 @@@ void *map_sha1_file(const unsigned cha
  
                if (!fstat(fd, &st)) {
                        *size = xsize_t(st.st_size);
 +                      if (!*size) {
 +                              /* mmap() is forbidden on empty files */
 +                              error("object file %s is empty", sha1_file_name(sha1));
 +                              return NULL;
 +                      }
                        map = xmmap(NULL, *size, PROT_READ, MAP_PRIVATE, fd, 0);
                }
                close(fd);
@@@ -2015,54 -2014,58 +2019,58 @@@ int is_pack_valid(struct packed_git *p
        return !open_packed_git(p);
  }
  
+ static int fill_pack_entry(const unsigned char *sha1,
+                          struct pack_entry *e,
+                          struct packed_git *p)
+ {
+       off_t offset;
+ 
+       if (p->num_bad_objects) {
+               unsigned i;
+               for (i = 0; i < p->num_bad_objects; i++)
+                       if (!hashcmp(sha1, p->bad_object_sha1 + 20 * i))
+                               return 0;
+       }
+ 
+       offset = find_pack_entry_one(sha1, p);
+       if (!offset)
+               return 0;
+ 
+       /*
+        * We are about to tell the caller where they can locate the
+        * requested object.  We better make sure the packfile is
+        * still here and can be accessed before supplying that
+        * answer, as it may have been deleted since the index was
+        * loaded!
+        */
+       if (!is_pack_valid(p)) {
+               warning("packfile %s cannot be accessed", p->pack_name);
+               return 0;
+       }
+       e->offset = offset;
+       e->p = p;
+       hashcpy(e->sha1, sha1);
+       return 1;
+ }
+ 
  static int find_pack_entry(const unsigned char *sha1, struct pack_entry *e)
  {
-       static struct packed_git *last_found = (void *)1;
        struct packed_git *p;
-       off_t offset;
  
        prepare_packed_git();
        if (!packed_git)
                return 0;
-       p = (last_found == (void *)1) ? packed_git : last_found;
  
-       do {
-               if (p->num_bad_objects) {
-                       unsigned i;
-                       for (i = 0; i < p->num_bad_objects; i++)
-                               if (!hashcmp(sha1, p->bad_object_sha1 + 20 * i))
-                                       goto next;
-               }
+       if (last_found_pack && fill_pack_entry(sha1, e, last_found_pack))
+               return 1;
  
-               offset = find_pack_entry_one(sha1, p);
-               if (offset) {
-                       /*
-                        * We are about to tell the caller where they can
-                        * locate the requested object.  We better make
-                        * sure the packfile is still here and can be
-                        * accessed before supplying that answer, as
-                        * it may have been deleted since the index
-                        * was loaded!
-                        */
-                       if (!is_pack_valid(p)) {
-                               warning("packfile %s cannot be accessed", p->pack_name);
-                               goto next;
-                       }
-                       e->offset = offset;
-                       e->p = p;
-                       hashcpy(e->sha1, sha1);
-                       last_found = p;
-                       return 1;
-               }
+       for (p = packed_git; p; p = p->next) {
+               if (p == last_found_pack || !fill_pack_entry(sha1, e, p))
+                       continue;
  
-               next:
-               if (p == last_found)
-                       p = packed_git;
-               else
-                       p = p->next;
-               if (p == last_found)
-                       p = p->next;
-       } while (p);
+               last_found_pack = p;
+               return 1;
+       }
        return 0;
  }