pack_refs(): split creation of packed refs and entry writing
Split pack_refs() into multiple passes: * Iterate over loose refs. For each one that can be turned into a packed ref, create a corresponding entry in the packed refs cache. * Write the packed refs to the packed-refs file. This change isolates the mutation of the packed-refs file to a single place. Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Michael Haggerty committed
Jun 20, 2013 at 10:37 UTC
267f9a8cc8192e120a6476fc55590e288e08b459
1 file changed
+34
-14
refs.c
+34
-14
@@ -2023,35 +2023,50 @@ struct ref_to_prune {
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struct pack_refs_cb_data {
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unsigned int flags;
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+ struct ref_dir *packed_refs;
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struct ref_to_prune *ref_to_prune;
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- int fd;
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};
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-static int pack_one_ref(struct ref_entry *entry, void *cb_data)
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+/*
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+ * An each_ref_entry_fn that is run over loose references only. If
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+ * the loose reference can be packed, add an entry in the packed ref
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+ * cache. If the reference should be pruned, also add it to
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+ * ref_to_prune in the pack_refs_cb_data.
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+ */
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+static int pack_if_possible_fn(struct ref_entry *entry, void *cb_data)
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{
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struct pack_refs_cb_data *cb = cb_data;
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enum peel_status peel_status;
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+ struct ref_entry *packed_entry;
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int is_tag_ref = !prefixcmp(entry->name, "refs/tags/");
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- /* ALWAYS pack refs that were already packed or are tags */
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- if (!(cb->flags & PACK_REFS_ALL) && !is_tag_ref &&
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- !(entry->flag & REF_ISPACKED))
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+ /* ALWAYS pack tags */
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+ if (!(cb->flags & PACK_REFS_ALL) && !is_tag_ref)
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return 0;
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/* Do not pack symbolic or broken refs: */
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if ((entry->flag & REF_ISSYMREF) || !ref_resolves_to_object(entry))
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return 0;
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+ /* Add a packed ref cache entry equivalent to the loose entry. */
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peel_status = peel_entry(entry, 1);
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if (peel_status != PEEL_PEELED && peel_status != PEEL_NON_TAG)
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die("internal error peeling reference %s (%s)",
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entry->name, sha1_to_hex(entry->u.value.sha1));
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- write_packed_entry(cb->fd, entry->name, entry->u.value.sha1,
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- peel_status == PEEL_PEELED ?
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- entry->u.value.peeled : NULL);
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+ packed_entry = find_ref(cb->packed_refs, entry->name);
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+ if (packed_entry) {
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+ /* Overwrite existing packed entry with info from loose entry */
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+ packed_entry->flag = REF_ISPACKED | REF_KNOWS_PEELED;
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+ hashcpy(packed_entry->u.value.sha1, entry->u.value.sha1);
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+ } else {
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+ packed_entry = create_ref_entry(entry->name, entry->u.value.sha1,
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+ REF_ISPACKED | REF_KNOWS_PEELED, 0);
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+ add_ref(cb->packed_refs, packed_entry);
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+ }
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+ hashcpy(packed_entry->u.value.peeled, entry->u.value.peeled);
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- /* If the ref was already packed, there is no need to prune it. */
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- if ((cb->flags & PACK_REFS_PRUNE) && !(entry->flag & REF_ISPACKED)) {
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+ /* Schedule the loose reference for pruning if requested. */
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+ if ((cb->flags & PACK_REFS_PRUNE)) {
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int namelen = strlen(entry->name) + 1;
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struct ref_to_prune *n = xcalloc(1, sizeof(*n) + namelen);
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hashcpy(n->sha1, entry->u.value.sha1);
@@ -2118,16 +2133,21 @@ static struct lock_file packlock;
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int pack_refs(unsigned int flags)
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{
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struct pack_refs_cb_data cbdata;
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+ int fd;
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memset(&cbdata, 0, sizeof(cbdata));
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cbdata.flags = flags;
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- cbdata.fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"),
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- LOCK_DIE_ON_ERROR);
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+ fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"),
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+ LOCK_DIE_ON_ERROR);
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+ cbdata.packed_refs = get_packed_refs(&ref_cache);
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- write_or_die(cbdata.fd, PACKED_REFS_HEADER, strlen(PACKED_REFS_HEADER));
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+ do_for_each_entry_in_dir(get_loose_refs(&ref_cache), 0,
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+ pack_if_possible_fn, &cbdata);
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+
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+ write_or_die(fd, PACKED_REFS_HEADER, strlen(PACKED_REFS_HEADER));
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+ do_for_each_entry_in_dir(cbdata.packed_refs, 0, write_packed_entry_fn, &fd);
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- do_for_each_entry(&ref_cache, "", pack_one_ref, &cbdata);
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if (commit_lock_file(&packlock) < 0)
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die_errno("unable to overwrite old ref-pack file");
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prune_refs(cbdata.ref_to_prune);