]> git.ipfire.org Git - thirdparty/git.git/blobdiff - refs.c
pack_refs(): split creation of packed refs and entry writing
[thirdparty/git.git] / refs.c
diff --git a/refs.c b/refs.c
index 42a7e17f6bdf6f03f56a012c87c137b80452ea17..9f1a007e3b4d08e888f378cc667635d2cbf79ecc 100644 (file)
--- a/refs.c
+++ b/refs.c
@@ -1998,6 +1998,23 @@ static void write_packed_entry(int fd, char *refname, unsigned char *sha1,
        }
 }
 
+/*
+ * An each_ref_entry_fn that writes the entry to a packed-refs file.
+ */
+static int write_packed_entry_fn(struct ref_entry *entry, void *cb_data)
+{
+       int *fd = cb_data;
+       enum peel_status peel_status = peel_entry(entry, 0);
+
+       if (peel_status != PEEL_PEELED && peel_status != PEEL_NON_TAG)
+               error("internal error: %s is not a valid packed reference!",
+                     entry->name);
+       write_packed_entry(*fd, entry->name, entry->u.value.sha1,
+                          peel_status == PEEL_PEELED ?
+                          entry->u.value.peeled : NULL);
+       return 0;
+}
+
 struct ref_to_prune {
        struct ref_to_prune *next;
        unsigned char sha1[20];
@@ -2006,35 +2023,50 @@ struct ref_to_prune {
 
 struct pack_refs_cb_data {
        unsigned int flags;
+       struct ref_dir *packed_refs;
        struct ref_to_prune *ref_to_prune;
-       int fd;
 };
 
-static int pack_one_ref(struct ref_entry *entry, void *cb_data)
+/*
+ * An each_ref_entry_fn that is run over loose references only.  If
+ * the loose reference can be packed, add an entry in the packed ref
+ * cache.  If the reference should be pruned, also add it to
+ * ref_to_prune in the pack_refs_cb_data.
+ */
+static int pack_if_possible_fn(struct ref_entry *entry, void *cb_data)
 {
        struct pack_refs_cb_data *cb = cb_data;
        enum peel_status peel_status;
+       struct ref_entry *packed_entry;
        int is_tag_ref = !prefixcmp(entry->name, "refs/tags/");
 
-       /* ALWAYS pack refs that were already packed or are tags */
-       if (!(cb->flags & PACK_REFS_ALL) && !is_tag_ref &&
-           !(entry->flag & REF_ISPACKED))
+       /* ALWAYS pack tags */
+       if (!(cb->flags & PACK_REFS_ALL) && !is_tag_ref)
                return 0;
 
        /* Do not pack symbolic or broken refs: */
        if ((entry->flag & REF_ISSYMREF) || !ref_resolves_to_object(entry))
                return 0;
 
+       /* Add a packed ref cache entry equivalent to the loose entry. */
        peel_status = peel_entry(entry, 1);
        if (peel_status != PEEL_PEELED && peel_status != PEEL_NON_TAG)
                die("internal error peeling reference %s (%s)",
                    entry->name, sha1_to_hex(entry->u.value.sha1));
-       write_packed_entry(cb->fd, entry->name, entry->u.value.sha1,
-                          peel_status == PEEL_PEELED ?
-                          entry->u.value.peeled : NULL);
+       packed_entry = find_ref(cb->packed_refs, entry->name);
+       if (packed_entry) {
+               /* Overwrite existing packed entry with info from loose entry */
+               packed_entry->flag = REF_ISPACKED | REF_KNOWS_PEELED;
+               hashcpy(packed_entry->u.value.sha1, entry->u.value.sha1);
+       } else {
+               packed_entry = create_ref_entry(entry->name, entry->u.value.sha1,
+                                               REF_ISPACKED | REF_KNOWS_PEELED, 0);
+               add_ref(cb->packed_refs, packed_entry);
+       }
+       hashcpy(packed_entry->u.value.peeled, entry->u.value.peeled);
 
-       /* If the ref was already packed, there is no need to prune it. */
-       if ((cb->flags & PACK_REFS_PRUNE) && !(entry->flag & REF_ISPACKED)) {
+       /* Schedule the loose reference for pruning if requested. */
+       if ((cb->flags & PACK_REFS_PRUNE)) {
                int namelen = strlen(entry->name) + 1;
                struct ref_to_prune *n = xcalloc(1, sizeof(*n) + namelen);
                hashcpy(n->sha1, entry->u.value.sha1);
@@ -2101,30 +2133,46 @@ static struct lock_file packlock;
 int pack_refs(unsigned int flags)
 {
        struct pack_refs_cb_data cbdata;
+       int fd;
 
        memset(&cbdata, 0, sizeof(cbdata));
        cbdata.flags = flags;
 
-       cbdata.fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"),
-                                             LOCK_DIE_ON_ERROR);
+       fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"),
+                                      LOCK_DIE_ON_ERROR);
+       cbdata.packed_refs = get_packed_refs(&ref_cache);
+
+       do_for_each_entry_in_dir(get_loose_refs(&ref_cache), 0,
+                                pack_if_possible_fn, &cbdata);
 
-       write_or_die(cbdata.fd, PACKED_REFS_HEADER, strlen(PACKED_REFS_HEADER));
+       write_or_die(fd, PACKED_REFS_HEADER, strlen(PACKED_REFS_HEADER));
+       do_for_each_entry_in_dir(cbdata.packed_refs, 0, write_packed_entry_fn, &fd);
 
-       do_for_each_entry(&ref_cache, "", pack_one_ref, &cbdata);
        if (commit_lock_file(&packlock) < 0)
                die_errno("unable to overwrite old ref-pack file");
        prune_refs(cbdata.ref_to_prune);
        return 0;
 }
 
-static int repack_ref_fn(struct ref_entry *entry, void *cb_data)
+/*
+ * 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)
 {
-       int *fd = cb_data;
-       enum peel_status peel_status;
+       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)) {
@@ -2134,7 +2182,7 @@ static int repack_ref_fn(struct ref_entry *entry, void *cb_data)
                if (read_ref_full(entry->name, sha1, 0, &flags))
                        /* We should at least have found the packed ref. */
                        die("Internal error");
-               if ((flags & REF_ISSYMREF) || !(flags & REF_ISPACKED))
+               if ((flags & REF_ISSYMREF) || !(flags & REF_ISPACKED)) {
                        /*
                         * This packed reference is overridden by a
                         * loose reference, so it is OK that its value
@@ -2143,9 +2191,11 @@ static int repack_ref_fn(struct ref_entry *entry, void *cb_data)
                         * collected.  For this purpose we don't even
                         * care whether the loose reference itself is
                         * invalid, broken, symbolic, etc.  Silently
-                        * omit the packed reference from the output.
+                        * 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
@@ -2154,14 +2204,10 @@ static int repack_ref_fn(struct ref_entry *entry, void *cb_data)
                 * the output.
                 */
                error("%s does not point to a valid object!", entry->name);
+               string_list_append(refs_to_delete, entry->name);
                return 0;
        }
 
-       peel_status = peel_entry(entry, 0);
-       write_packed_entry(*fd, entry->name, entry->u.value.sha1,
-                          peel_status == PEEL_PEELED ?
-                          entry->u.value.peeled : NULL);
-
        return 0;
 }
 
@@ -2169,6 +2215,8 @@ static int repack_without_ref(const char *refname)
 {
        int fd;
        struct ref_dir *packed;
+       struct string_list refs_to_delete = STRING_LIST_INIT_DUP;
+       struct string_list_item *ref_to_delete;
 
        if (!get_packed_ref(refname))
                return 0; /* refname does not exist in packed refs */
@@ -2180,7 +2228,8 @@ static int repack_without_ref(const char *refname)
        }
        clear_packed_ref_cache(&ref_cache);
        packed = get_packed_refs(&ref_cache);
-       /* Remove refname from the cache. */
+
+       /* Remove refname from the cache: */
        if (remove_entry(packed, refname) == -1) {
                /*
                 * The packed entry disappeared while we were
@@ -2189,8 +2238,17 @@ static int repack_without_ref(const char *refname)
                rollback_lock_file(&packlock);
                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: */
        write_or_die(fd, PACKED_REFS_HEADER, strlen(PACKED_REFS_HEADER));
-       do_for_each_entry_in_dir(packed, 0, repack_ref_fn, &fd);
+       do_for_each_entry_in_dir(packed, 0, write_packed_entry_fn, &fd);
        return commit_lock_file(&packlock);
 }