diff options
Diffstat (limited to 'refs.c')
-rw-r--r-- | refs.c | 59 |
1 files changed, 56 insertions, 3 deletions
@@ -1806,8 +1806,10 @@ static int refs_read_special_head(struct ref_store *ref_store, int result = -1; strbuf_addf(&full_path, "%s/%s", ref_store->gitdir, refname); - if (strbuf_read_file(&content, full_path.buf, 0) < 0) + if (strbuf_read_file(&content, full_path.buf, 0) < 0) { + *failure_errno = errno; goto done; + } result = parse_loose_ref_contents(content.buf, oid, referent, type, failure_errno); @@ -1818,15 +1820,66 @@ done: return result; } +static int is_special_ref(const char *refname) +{ + /* + * Special references get written and read directly via the filesystem + * by the subsystems that create them. Thus, they must not go through + * the reference backend but must instead be read directly. It is + * arguable whether this behaviour is sensible, or whether it's simply + * a leaky abstraction enabled by us only having a single reference + * backend implementation. But at least for a subset of references it + * indeed does make sense to treat them specially: + * + * - FETCH_HEAD may contain multiple object IDs, and each one of them + * carries additional metadata like where it came from. + * + * - MERGE_HEAD may contain multiple object IDs when merging multiple + * heads. + * + * There are some exceptions that you might expect to see on this list + * but which are handled exclusively via the reference backend: + * + * - BISECT_EXPECTED_REV + * + * - CHERRY_PICK_HEAD + * + * - HEAD + * + * - ORIG_HEAD + * + * - "rebase-apply/" and "rebase-merge/" contain all of the state for + * rebases, including some reference-like files. These are + * exclusively read and written via the filesystem and never go + * through the refdb. + * + * Writing or deleting references must consistently go either through + * the filesystem (special refs) or through the reference backend + * (normal ones). + */ + static const char * const special_refs[] = { + "AUTO_MERGE", + "FETCH_HEAD", + "MERGE_AUTOSTASH", + "MERGE_HEAD", + }; + size_t i; + + for (i = 0; i < ARRAY_SIZE(special_refs); i++) + if (!strcmp(refname, special_refs[i])) + return 1; + + return 0; +} + int refs_read_raw_ref(struct ref_store *ref_store, const char *refname, struct object_id *oid, struct strbuf *referent, unsigned int *type, int *failure_errno) { assert(failure_errno); - if (!strcmp(refname, "FETCH_HEAD") || !strcmp(refname, "MERGE_HEAD")) { + if (is_special_ref(refname)) return refs_read_special_head(ref_store, refname, oid, referent, type, failure_errno); - } return ref_store->be->read_raw_ref(ref_store, refname, oid, referent, type, failure_errno); |