Merge branch 'bp/fsmonitor'
[gitweb.git] / refs / packed-backend.c
index 8beb99652f5d79a92cc7b61359bc08ab3067bfca..65288c647278aa27790b13c0360f756686dadf7a 100644 (file)
@@ -458,10 +458,13 @@ static void verify_buffer_safe(struct snapshot *snapshot)
                                 last_line, eof - last_line);
 }
 
+#define SMALL_FILE_SIZE (32*1024)
+
 /*
  * Depending on `mmap_strategy`, either mmap or read the contents of
  * the `packed-refs` file into the snapshot. Return 1 if the file
- * existed and was read, or 0 if the file was absent. Die on errors.
+ * existed and was read, or 0 if the file was absent or empty. Die on
+ * errors.
  */
 static int load_contents(struct snapshot *snapshot)
 {
@@ -492,19 +495,17 @@ static int load_contents(struct snapshot *snapshot)
                die_errno("couldn't stat %s", snapshot->refs->path);
        size = xsize_t(st.st_size);
 
-       switch (mmap_strategy) {
-       case MMAP_NONE:
+       if (!size) {
+               return 0;
+       } else if (mmap_strategy == MMAP_NONE || size <= SMALL_FILE_SIZE) {
                snapshot->buf = xmalloc(size);
                bytes_read = read_in_full(fd, snapshot->buf, size);
                if (bytes_read < 0 || bytes_read != size)
                        die_errno("couldn't read %s", snapshot->refs->path);
                snapshot->mmapped = 0;
-               break;
-       case MMAP_TEMPORARY:
-       case MMAP_OK:
+       } else {
                snapshot->buf = xmmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, 0);
                snapshot->mmapped = 1;
-               break;
        }
        close(fd);
 
@@ -519,9 +520,11 @@ static int load_contents(struct snapshot *snapshot)
  * `refname` starts. If `mustexist` is true and the reference doesn't
  * exist, then return NULL. If `mustexist` is false and the reference
  * doesn't exist, then return the point where that reference would be
- * inserted. In the latter mode, `refname` doesn't have to be a proper
- * reference name; for example, one could search for "refs/replace/"
- * to find the start of any replace references.
+ * inserted, or `snapshot->eof` (which might be NULL) if it would be
+ * inserted at the end of the file. In the latter mode, `refname`
+ * doesn't have to be a proper reference name; for example, one could
+ * search for "refs/replace/" to find the start of any replace
+ * references.
  *
  * The record is sought using a binary search, so `snapshot->buf` must
  * be sorted.
@@ -551,7 +554,7 @@ static const char *find_reference_location(struct snapshot *snapshot,
         */
        const char *hi = snapshot->eof;
 
-       while (lo < hi) {
+       while (lo != hi) {
                const char *mid, *rec;
                int cmp;
 
@@ -717,7 +720,7 @@ static struct snapshot *get_snapshot(struct packed_ref_store *refs)
 }
 
 static int packed_read_raw_ref(struct ref_store *ref_store,
-                              const char *refname, unsigned char *sha1,
+                              const char *refname, struct object_id *oid,
                               struct strbuf *referent, unsigned int *type)
 {
        struct packed_ref_store *refs =
@@ -735,7 +738,7 @@ static int packed_read_raw_ref(struct ref_store *ref_store,
                return -1;
        }
 
-       if (get_sha1_hex(rec, sha1))
+       if (get_oid_hex(rec, oid))
                die_invalid_line(refs->path, rec, snapshot->eof - rec);
 
        *type = REF_ISPACKED;
@@ -745,7 +748,7 @@ static int packed_read_raw_ref(struct ref_store *ref_store,
 /*
  * This value is set in `base.flags` if the peeled value of the
  * current reference is known. In that case, `peeled` contains the
- * correct peeled value for the reference, which might be `null_sha1`
+ * correct peeled value for the reference, which might be `null_oid`
  * if the reference is not a tag or if it is broken.
  */
 #define REF_KNOWS_PEELED 0x40
@@ -881,7 +884,7 @@ static int packed_ref_iterator_peel(struct ref_iterator *ref_iterator,
        } else if ((iter->base.flags & (REF_ISBROKEN | REF_ISSYMREF))) {
                return -1;
        } else {
-               return !!peel_object(iter->oid.hash, peeled->hash);
+               return !!peel_object(&iter->oid, peeled);
        }
 }
 
@@ -925,7 +928,12 @@ static struct ref_iterator *packed_ref_iterator_begin(
         */
        snapshot = get_snapshot(refs);
 
-       if (!snapshot->buf)
+       if (prefix && *prefix)
+               start = find_reference_location(snapshot, prefix, 0);
+       else
+               start = snapshot->start;
+
+       if (start == snapshot->eof)
                return empty_ref_iterator_begin();
 
        iter = xcalloc(1, sizeof(*iter));
@@ -935,11 +943,6 @@ static struct ref_iterator *packed_ref_iterator_begin(
        iter->snapshot = snapshot;
        acquire_snapshot(snapshot);
 
-       if (prefix && *prefix)
-               start = find_reference_location(snapshot, prefix, 0);
-       else
-               start = snapshot->start;
-
        iter->pos = start;
        iter->eof = snapshot->eof;
        strbuf_init(&iter->refname_buf, 0);
@@ -962,11 +965,11 @@ static struct ref_iterator *packed_ref_iterator_begin(
  * by the failing call to `fprintf()`.
  */
 static int write_packed_entry(FILE *fh, const char *refname,
-                             const unsigned char *sha1,
-                             const unsigned char *peeled)
+                             const struct object_id *oid,
+                             const struct object_id *peeled)
 {
-       if (fprintf(fh, "%s %s\n", sha1_to_hex(sha1), refname) < 0 ||
-           (peeled && fprintf(fh, "^%s\n", sha1_to_hex(peeled)) < 0))
+       if (fprintf(fh, "%s %s\n", oid_to_hex(oid), refname) < 0 ||
+           (peeled && fprintf(fh, "^%s\n", oid_to_hex(peeled)) < 0))
                return -1;
 
        return 0;
@@ -1204,8 +1207,8 @@ static int write_with_updates(struct packed_ref_store *refs,
                        int peel_error = ref_iterator_peel(iter, &peeled);
 
                        if (write_packed_entry(out, iter->refname,
-                                              iter->oid->hash,
-                                              peel_error ? NULL : peeled.hash))
+                                              iter->oid,
+                                              peel_error ? NULL : &peeled))
                                goto write_error;
 
                        if ((ok = ref_iterator_advance(iter)) != ITER_OK)
@@ -1221,12 +1224,12 @@ static int write_with_updates(struct packed_ref_store *refs,
                        i++;
                } else {
                        struct object_id peeled;
-                       int peel_error = peel_object(update->new_oid.hash,
-                                                    peeled.hash);
+                       int peel_error = peel_object(&update->new_oid,
+                                                    &peeled);
 
                        if (write_packed_entry(out, update->refname,
-                                              update->new_oid.hash,
-                                              peel_error ? NULL : peeled.hash))
+                                              &update->new_oid,
+                                              peel_error ? NULL : &peeled))
                                goto write_error;
 
                        i++;
@@ -1341,7 +1344,7 @@ int is_packed_transaction_needed(struct ref_store *ref_store,
                        continue;
 
                if (!refs_read_raw_ref(ref_store, update->refname,
-                                      oid.hash, &referent, &type) ||
+                                      &oid, &referent, &type) ||
                    errno != ENOENT) {
                        /*
                         * We have to actually delete that reference
@@ -1614,7 +1617,7 @@ static int packed_delete_reflog(struct ref_store *ref_store,
 }
 
 static int packed_reflog_expire(struct ref_store *ref_store,
-                               const char *refname, const unsigned char *sha1,
+                               const char *refname, const struct object_id *oid,
                                unsigned int flags,
                                reflog_expiry_prepare_fn prepare_fn,
                                reflog_expiry_should_prune_fn should_prune_fn,