replace-object.h

   1 #ifndef REPLACE_OBJECT_H
   2 #define REPLACE_OBJECT_H
   3
   4 #include "oidmap.h"
   5 #include "repository.h"
   6 #include "object-store-ll.h"
   7
   8 struct replace_object {
   9         struct oidmap_entry original;
  10         struct object_id replacement;
  11 };
  12
  13 void prepare_replace_object(struct repository *r);
  14
  15 /*
  16  * This internal function is only declared here for the benefit of
  17  * lookup_replace_object().  Please do not call it directly.
  18  */
  19 const struct object_id *do_lookup_replace_object(struct repository *r,
  20                                                  const struct object_id *oid);
  21
  22 /*
  23  * Some commands disable replace-refs unconditionally, and otherwise each
  24  * repository could alter the core.useReplaceRefs config value.
  25  *
  26  * Return 1 if and only if all of the following are true:
  27  *
  28  *  a. disable_replace_refs() has not been called.
  29  *  b. GIT_NO_REPLACE_OBJECTS is unset or zero.
  30  *  c. the given repository does not have core.useReplaceRefs=false.
  31  */
  32 int replace_refs_enabled(struct repository *r);
  33
  34 /*
  35  * If object sha1 should be replaced, return the replacement object's
  36  * name (replaced recursively, if necessary).  The return value is
  37  * either sha1 or a pointer to a permanently-allocated value.  When
  38  * object replacement is suppressed, always return sha1.
  39  *
  40  * Note: some thread debuggers might point a data race on the
  41  * replace_map_initialized reading in this function. However, we know there's no
  42  * problem in the value being updated by one thread right after another one read
  43  * it here (and it should be written to only once, anyway).
  44  */
  45 static inline const struct object_id *lookup_replace_object(struct repository *r,
  46                                                             const struct object_id *oid)
  47 {
  48         if (!replace_refs_enabled(r) ||
  49             (r->objects->replace_map_initialized &&
  50              r->objects->replace_map->map.tablesize == 0))
  51                 return oid;
  52         return do_lookup_replace_object(r, oid);
  53 }
  54
  55 /*
  56  * Some commands override config and environment settings for using
  57  * replace references. Use this method to disable the setting and ensure
  58  * those other settings will not override this choice. This applies
  59  * globally to all in-process repositories.
  60  */
  61 void disable_replace_refs(void);
  62
  63 #endif /* REPLACE_OBJECT_H */