upload-pack: optionally allow fetching reachable sha1
[gitweb.git] / refs.c
diff --git a/refs.c b/refs.c
index 8d46b08055ef9cb151c1868a0354fd906b0bcddf..47e4e5380a1e0fc04f8b81837c51c023f35871cf 100644 (file)
--- a/refs.c
+++ b/refs.c
@@ -12,7 +12,6 @@ struct ref_lock {
        struct lock_file *lk;
        unsigned char old_sha1[20];
        int lock_fd;
-       int force_write;
 };
 
 /*
@@ -1935,6 +1934,11 @@ static int do_for_each_ref(struct ref_cache *refs, const char *base,
        data.fn = fn;
        data.cb_data = cb_data;
 
+       if (ref_paranoia < 0)
+               ref_paranoia = git_env_bool("GIT_REF_PARANOIA", 0);
+       if (ref_paranoia)
+               data.flags |= DO_FOR_EACH_INCLUDE_BROKEN;
+
        return do_for_each_entry(refs, base, do_one_ref, &data);
 }
 
@@ -2277,7 +2281,6 @@ static struct ref_lock *lock_ref_sha1_basic(const char *refname,
        int type, lflags;
        int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
        int resolve_flags = 0;
-       int missing = 0;
        int attempts_remaining = 3;
 
        lock = xcalloc(1, sizeof(struct ref_lock));
@@ -2316,13 +2319,13 @@ static struct ref_lock *lock_ref_sha1_basic(const char *refname,
                        orig_refname, strerror(errno));
                goto error_return;
        }
-       missing = is_null_sha1(lock->old_sha1);
-       /* When the ref did not exist and we are creating it,
-        * make sure there is no existing ref that is packed
-        * whose name begins with our refname, nor a ref whose
-        * name is a proper prefix of our refname.
+       /*
+        * If the ref did not exist and we are creating it, make sure
+        * there is no existing packed ref whose name begins with our
+        * refname, nor a packed ref whose name is a proper prefix of
+        * our refname.
         */
-       if (missing &&
+       if (is_null_sha1(lock->old_sha1) &&
             !is_refname_available(refname, skip, get_packed_refs(&ref_cache))) {
                last_errno = ENOTDIR;
                goto error_return;
@@ -2338,10 +2341,6 @@ static struct ref_lock *lock_ref_sha1_basic(const char *refname,
        lock->ref_name = xstrdup(refname);
        lock->orig_ref_name = xstrdup(orig_refname);
        ref_file = git_path("%s", refname);
-       if (missing)
-               lock->force_write = 1;
-       if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
-               lock->force_write = 1;
 
  retry:
        switch (safe_create_leading_directories(ref_file)) {
@@ -2622,68 +2621,10 @@ int pack_refs(unsigned int flags)
        return 0;
 }
 
-/*
- * If entry is no longer needed in packed-refs, add it to the string
- * list pointed to by cb_data.  Reasons for deleting entries:
- *
- * - Entry is broken.
- * - Entry is overridden by a loose ref.
- * - Entry does not point at a valid object.
- *
- * In the first and third cases, also emit an error message because these
- * are indications of repository corruption.
- */
-static int curate_packed_ref_fn(struct ref_entry *entry, void *cb_data)
-{
-       struct string_list *refs_to_delete = cb_data;
-
-       if (entry->flag & REF_ISBROKEN) {
-               /* This shouldn't happen to packed refs. */
-               error("%s is broken!", entry->name);
-               string_list_append(refs_to_delete, entry->name);
-               return 0;
-       }
-       if (!has_sha1_file(entry->u.value.sha1)) {
-               unsigned char sha1[20];
-               int flags;
-
-               if (read_ref_full(entry->name, 0, sha1, &flags))
-                       /* We should at least have found the packed ref. */
-                       die("Internal error");
-               if ((flags & REF_ISSYMREF) || !(flags & REF_ISPACKED)) {
-                       /*
-                        * This packed reference is overridden by a
-                        * loose reference, so it is OK that its value
-                        * is no longer valid; for example, it might
-                        * refer to an object that has been garbage
-                        * collected.  For this purpose we don't even
-                        * care whether the loose reference itself is
-                        * invalid, broken, symbolic, etc.  Silently
-                        * remove the packed reference.
-                        */
-                       string_list_append(refs_to_delete, entry->name);
-                       return 0;
-               }
-               /*
-                * There is no overriding loose reference, so the fact
-                * that this reference doesn't refer to a valid object
-                * indicates some kind of repository corruption.
-                * Report the problem, then omit the reference from
-                * the output.
-                */
-               error("%s does not point to a valid object!", entry->name);
-               string_list_append(refs_to_delete, entry->name);
-               return 0;
-       }
-
-       return 0;
-}
-
 int repack_without_refs(struct string_list *refnames, struct strbuf *err)
 {
        struct ref_dir *packed;
-       struct string_list refs_to_delete = STRING_LIST_INIT_DUP;
-       struct string_list_item *refname, *ref_to_delete;
+       struct string_list_item *refname;
        int ret, needs_repacking = 0, removed = 0;
 
        assert(err);
@@ -2719,13 +2660,6 @@ int repack_without_refs(struct string_list *refnames, struct strbuf *err)
                return 0;
        }
 
-       /* Remove any other accumulated cruft */
-       do_for_each_entry_in_dir(packed, 0, curate_packed_ref_fn, &refs_to_delete);
-       for_each_string_list_item(ref_to_delete, &refs_to_delete) {
-               if (remove_entry(packed, ref_to_delete->string) == -1)
-                       die("internal error");
-       }
-
        /* Write what remains */
        ret = commit_packed_refs();
        if (ret)
@@ -2897,7 +2831,6 @@ int rename_ref(const char *oldrefname, const char *newrefname, const char *logms
                error("unable to lock %s for update", newrefname);
                goto rollback;
        }
-       lock->force_write = 1;
        hashcpy(lock->old_sha1, orig_sha1);
        if (write_ref_sha1(lock, orig_sha1, logmsg)) {
                error("unable to write current sha1 into %s", newrefname);
@@ -2913,7 +2846,6 @@ int rename_ref(const char *oldrefname, const char *newrefname, const char *logms
                goto rollbacklog;
        }
 
-       lock->force_write = 1;
        flag = log_all_ref_updates;
        log_all_ref_updates = 0;
        if (write_ref_sha1(lock, orig_sha1, NULL))
@@ -3099,14 +3031,6 @@ static int write_ref_sha1(struct ref_lock *lock,
        static char term = '\n';
        struct object *o;
 
-       if (!lock) {
-               errno = EINVAL;
-               return -1;
-       }
-       if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
-               unlock_ref(lock);
-               return 0;
-       }
        o = parse_object(sha1);
        if (!o) {
                error("Trying to write ref %s with nonexistent object %s",
@@ -3851,15 +3775,28 @@ int ref_transaction_commit(struct ref_transaction *transaction,
                int flags = update->flags;
 
                if ((flags & REF_HAVE_NEW) && !is_null_sha1(update->new_sha1)) {
-                       if (write_ref_sha1(update->lock, update->new_sha1,
-                                          update->msg)) {
+                       int overwriting_symref = ((update->type & REF_ISSYMREF) &&
+                                                 (update->flags & REF_NODEREF));
+
+                       if (!overwriting_symref
+                           && !hashcmp(update->lock->old_sha1, update->new_sha1)) {
+                               /*
+                                * The reference already has the desired
+                                * value, so we don't need to write it.
+                                */
+                               unlock_ref(update->lock);
+                               update->lock = NULL;
+                       } else if (write_ref_sha1(update->lock, update->new_sha1,
+                                                 update->msg)) {
                                update->lock = NULL; /* freed by write_ref_sha1 */
                                strbuf_addf(err, "Cannot update the ref '%s'.",
                                            update->refname);
                                ret = TRANSACTION_GENERIC_ERROR;
                                goto cleanup;
+                       } else {
+                               /* freed by write_ref_sha1(): */
+                               update->lock = NULL;
                        }
-                       update->lock = NULL; /* freed by write_ref_sha1 */
                }
        }
 
@@ -4083,6 +4020,7 @@ int reflog_expire(const char *refname, const unsigned char *sha1,
        struct ref_lock *lock;
        char *log_file;
        int status = 0;
+       int type;
 
        memset(&cb, 0, sizeof(cb));
        cb.flags = flags;
@@ -4094,7 +4032,7 @@ int reflog_expire(const char *refname, const unsigned char *sha1,
         * reference itself, plus we might need to update the
         * reference if --updateref was specified:
         */
-       lock = lock_ref_sha1_basic(refname, sha1, NULL, 0, NULL);
+       lock = lock_ref_sha1_basic(refname, sha1, NULL, 0, &type);
        if (!lock)
                return error("cannot lock ref '%s'", refname);
        if (!reflog_exists(refname)) {
@@ -4131,10 +4069,21 @@ int reflog_expire(const char *refname, const unsigned char *sha1,
        (*cleanup_fn)(cb.policy_cb);
 
        if (!(flags & EXPIRE_REFLOGS_DRY_RUN)) {
+               /*
+                * It doesn't make sense to adjust a reference pointed
+                * to by a symbolic ref based on expiring entries in
+                * the symbolic reference's reflog. Nor can we update
+                * a reference if there are no remaining reflog
+                * entries.
+                */
+               int update = (flags & EXPIRE_REFLOGS_UPDATE_REF) &&
+                       !(type & REF_ISSYMREF) &&
+                       !is_null_sha1(cb.last_kept_sha1);
+
                if (close_lock_file(&reflog_lock)) {
                        status |= error("couldn't write %s: %s", log_file,
                                        strerror(errno));
-               } else if ((flags & EXPIRE_REFLOGS_UPDATE_REF) &&
+               } else if (update &&
                        (write_in_full(lock->lock_fd,
                                sha1_to_hex(cb.last_kept_sha1), 40) != 40 ||
                         write_str_in_full(lock->lock_fd, "\n") != 1 ||
@@ -4145,7 +4094,7 @@ int reflog_expire(const char *refname, const unsigned char *sha1,
                } else if (commit_lock_file(&reflog_lock)) {
                        status |= error("unable to commit reflog '%s' (%s)",
                                        log_file, strerror(errno));
-               } else if ((flags & EXPIRE_REFLOGS_UPDATE_REF) && commit_ref(lock)) {
+               } else if (update && commit_ref(lock)) {
                        status |= error("couldn't set %s", lock->ref_name);
                }
        }