summaryrefslogtreecommitdiffstats
path: root/refs
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-20 05:14:36 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-20 05:14:36 +0000
commit037de004c68d704abf839eebe075c58c9603f8f3 (patch)
tree7ac13a7fbb70193e7d04fc193f75de839e914d45 /refs
parentAdding upstream version 1:2.43.0. (diff)
downloadgit-037de004c68d704abf839eebe075c58c9603f8f3.tar.xz
git-037de004c68d704abf839eebe075c58c9603f8f3.zip
Adding upstream version 1:2.45.1.upstream/1%2.45.1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'refs')
-rw-r--r--refs/debug.c23
-rw-r--r--refs/files-backend.c271
-rw-r--r--refs/iterator.c69
-rw-r--r--refs/packed-backend.c55
-rw-r--r--refs/ref-cache.c3
-rw-r--r--refs/refs-internal.h42
-rw-r--r--refs/reftable-backend.c2242
7 files changed, 2451 insertions, 254 deletions
diff --git a/refs/debug.c b/refs/debug.c
index b7ffc4c..c7531b1 100644
--- a/refs/debug.c
+++ b/refs/debug.c
@@ -33,10 +33,10 @@ struct ref_store *maybe_debug_wrap_ref_store(const char *gitdir, struct ref_stor
return (struct ref_store *)res;
}
-static int debug_init_db(struct ref_store *refs, struct strbuf *err)
+static int debug_init_db(struct ref_store *refs, int flags, struct strbuf *err)
{
struct debug_ref_store *drefs = (struct debug_ref_store *)refs;
- int res = drefs->refs->be->init_db(drefs->refs, err);
+ int res = drefs->refs->be->init_db(drefs->refs, flags, err);
trace_printf_key(&trace_refs, "init_db: %d\n", res);
return res;
}
@@ -143,20 +143,6 @@ static int debug_create_symref(struct ref_store *ref_store,
return res;
}
-static int debug_delete_refs(struct ref_store *ref_store, const char *msg,
- struct string_list *refnames, unsigned int flags)
-{
- struct debug_ref_store *drefs = (struct debug_ref_store *)ref_store;
- int res =
- drefs->refs->be->delete_refs(drefs->refs, msg, refnames, flags);
- int i;
- trace_printf_key(&trace_refs, "delete_refs {\n");
- for (i = 0; i < refnames->nr; i++)
- trace_printf_key(&trace_refs, "%s\n", refnames->items[i].string);
- trace_printf_key(&trace_refs, "}: %d\n", res);
- return res;
-}
-
static int debug_rename_ref(struct ref_store *ref_store, const char *oldref,
const char *newref, const char *logmsg)
{
@@ -195,7 +181,6 @@ static int debug_ref_iterator_advance(struct ref_iterator *ref_iterator)
trace_printf_key(&trace_refs, "iterator_advance: %s (0)\n",
diter->iter->refname);
- diter->base.ordered = diter->iter->ordered;
diter->base.refname = diter->iter->refname;
diter->base.oid = diter->iter->oid;
diter->base.flags = diter->iter->flags;
@@ -236,7 +221,7 @@ debug_ref_iterator_begin(struct ref_store *ref_store, const char *prefix,
drefs->refs->be->iterator_begin(drefs->refs, prefix,
exclude_patterns, flags);
struct debug_ref_iterator *diter = xcalloc(1, sizeof(*diter));
- base_ref_iterator_init(&diter->base, &debug_ref_iterator_vtable, 1);
+ base_ref_iterator_init(&diter->base, &debug_ref_iterator_vtable);
diter->iter = res;
trace_printf_key(&trace_refs, "ref_iterator_begin: \"%s\" (0x%x)\n",
prefix, flags);
@@ -440,7 +425,6 @@ static int debug_reflog_expire(struct ref_store *ref_store, const char *refname,
}
struct ref_storage_be refs_be_debug = {
- .next = NULL,
.name = "debug",
.init = NULL,
.init_db = debug_init_db,
@@ -458,7 +442,6 @@ struct ref_storage_be refs_be_debug = {
.pack_refs = debug_pack_refs,
.create_symref = debug_create_symref,
- .delete_refs = debug_delete_refs,
.rename_ref = debug_rename_ref,
.copy_ref = debug_copy_ref,
diff --git a/refs/files-backend.c b/refs/files-backend.c
index db5c0c7..a098d14 100644
--- a/refs/files-backend.c
+++ b/refs/files-backend.c
@@ -1,5 +1,4 @@
#include "../git-compat-util.h"
-#include "../config.h"
#include "../copy.h"
#include "../environment.h"
#include "../gettext.h"
@@ -19,7 +18,6 @@
#include "../dir.h"
#include "../chdir-notify.h"
#include "../setup.h"
-#include "../worktree.h"
#include "../wrapper.h"
#include "../write-or-die.h"
#include "../revision.h"
@@ -231,6 +229,38 @@ static void add_per_worktree_entries_to_dir(struct ref_dir *dir, const char *dir
}
}
+static void loose_fill_ref_dir_regular_file(struct files_ref_store *refs,
+ const char *refname,
+ struct ref_dir *dir)
+{
+ struct object_id oid;
+ int flag;
+
+ if (!refs_resolve_ref_unsafe(&refs->base, refname, RESOLVE_REF_READING,
+ &oid, &flag)) {
+ oidclr(&oid);
+ flag |= REF_ISBROKEN;
+ } else if (is_null_oid(&oid)) {
+ /*
+ * It is so astronomically unlikely
+ * that null_oid is the OID of an
+ * actual object that we consider its
+ * appearance in a loose reference
+ * file to be repo corruption
+ * (probably due to a software bug).
+ */
+ flag |= REF_ISBROKEN;
+ }
+
+ if (check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
+ if (!refname_is_safe(refname))
+ die("loose refname is dangerous: %s", refname);
+ oidclr(&oid);
+ flag |= REF_BAD_NAME | REF_ISBROKEN;
+ }
+ add_entry_to_dir(dir, create_ref_entry(refname, &oid, flag));
+}
+
/*
* Read the loose references from the namespace dirname into dir
* (without recursing). dirname must end with '/'. dir must be the
@@ -259,8 +289,6 @@ static void loose_fill_ref_dir(struct ref_store *ref_store,
strbuf_add(&refname, dirname, dirnamelen);
while ((de = readdir(d)) != NULL) {
- struct object_id oid;
- int flag;
unsigned char dtype;
if (de->d_name[0] == '.')
@@ -276,33 +304,7 @@ static void loose_fill_ref_dir(struct ref_store *ref_store,
create_dir_entry(dir->cache, refname.buf,
refname.len));
} else if (dtype == DT_REG) {
- if (!refs_resolve_ref_unsafe(&refs->base,
- refname.buf,
- RESOLVE_REF_READING,
- &oid, &flag)) {
- oidclr(&oid);
- flag |= REF_ISBROKEN;
- } else if (is_null_oid(&oid)) {
- /*
- * It is so astronomically unlikely
- * that null_oid is the OID of an
- * actual object that we consider its
- * appearance in a loose reference
- * file to be repo corruption
- * (probably due to a software bug).
- */
- flag |= REF_ISBROKEN;
- }
-
- if (check_refname_format(refname.buf,
- REFNAME_ALLOW_ONELEVEL)) {
- if (!refname_is_safe(refname.buf))
- die("loose refname is dangerous: %s", refname.buf);
- oidclr(&oid);
- flag |= REF_BAD_NAME | REF_ISBROKEN;
- }
- add_entry_to_dir(dir,
- create_ref_entry(refname.buf, &oid, flag));
+ loose_fill_ref_dir_regular_file(refs, refname.buf, dir);
}
strbuf_setlen(&refname, dirnamelen);
}
@@ -313,9 +315,59 @@ static void loose_fill_ref_dir(struct ref_store *ref_store,
add_per_worktree_entries_to_dir(dir, dirname);
}
-static struct ref_cache *get_loose_ref_cache(struct files_ref_store *refs)
+/*
+ * Add pseudorefs to the ref dir by parsing the directory for any files
+ * which follow the pseudoref syntax.
+ */
+static void add_pseudoref_and_head_entries(struct ref_store *ref_store,
+ struct ref_dir *dir,
+ const char *dirname)
+{
+ struct files_ref_store *refs =
+ files_downcast(ref_store, REF_STORE_READ, "fill_ref_dir");
+ struct strbuf path = STRBUF_INIT, refname = STRBUF_INIT;
+ struct dirent *de;
+ size_t dirnamelen;
+ DIR *d;
+
+ files_ref_path(refs, &path, dirname);
+
+ d = opendir(path.buf);
+ if (!d) {
+ strbuf_release(&path);
+ return;
+ }
+
+ strbuf_addstr(&refname, dirname);
+ dirnamelen = refname.len;
+
+ while ((de = readdir(d)) != NULL) {
+ unsigned char dtype;
+
+ if (de->d_name[0] == '.')
+ continue;
+ if (ends_with(de->d_name, ".lock"))
+ continue;
+ strbuf_addstr(&refname, de->d_name);
+
+ dtype = get_dtype(de, &path, 1);
+ if (dtype == DT_REG && (is_pseudoref(ref_store, de->d_name) ||
+ is_headref(ref_store, de->d_name)))
+ loose_fill_ref_dir_regular_file(refs, refname.buf, dir);
+
+ strbuf_setlen(&refname, dirnamelen);
+ }
+ strbuf_release(&refname);
+ strbuf_release(&path);
+ closedir(d);
+}
+
+static struct ref_cache *get_loose_ref_cache(struct files_ref_store *refs,
+ unsigned int flags)
{
if (!refs->loose) {
+ struct ref_dir *dir;
+
/*
* Mark the top-level directory complete because we
* are about to read the only subdirectory that can
@@ -326,12 +378,17 @@ static struct ref_cache *get_loose_ref_cache(struct files_ref_store *refs)
/* We're going to fill the top level ourselves: */
refs->loose->root->flag &= ~REF_INCOMPLETE;
+ dir = get_ref_dir(refs->loose->root);
+
+ if (flags & DO_FOR_EACH_INCLUDE_ROOT_REFS)
+ add_pseudoref_and_head_entries(dir->cache->ref_store, dir,
+ refs->loose->root->name);
+
/*
* Add an incomplete entry for "refs/" (to be filled
* lazily):
*/
- add_entry_to_dir(get_ref_dir(refs->loose->root),
- create_dir_entry(refs->loose, "refs/", 5));
+ add_entry_to_dir(dir, create_dir_entry(refs->loose, "refs/", 5));
}
return refs->loose;
}
@@ -859,7 +916,7 @@ static struct ref_iterator *files_ref_iterator_begin(
* disk, and re-reads it if not.
*/
- loose_iter = cache_ref_iterator_begin(get_loose_ref_cache(refs),
+ loose_iter = cache_ref_iterator_begin(get_loose_ref_cache(refs, flags),
prefix, ref_store->repo, 1);
/*
@@ -881,8 +938,7 @@ static struct ref_iterator *files_ref_iterator_begin(
CALLOC_ARRAY(iter, 1);
ref_iterator = &iter->base;
- base_ref_iterator_init(ref_iterator, &files_ref_iterator_vtable,
- overlay_iter->ordered);
+ base_ref_iterator_init(ref_iterator, &files_ref_iterator_vtable);
iter->iter0 = overlay_iter;
iter->repo = ref_store->repo;
iter->flags = flags;
@@ -1220,7 +1276,7 @@ static int files_pack_refs(struct ref_store *ref_store,
packed_refs_lock(refs->packed_ref_store, LOCK_DIE_ON_ERROR, &err);
- iter = cache_ref_iterator_begin(get_loose_ref_cache(refs), NULL,
+ iter = cache_ref_iterator_begin(get_loose_ref_cache(refs, 0), NULL,
the_repository, 0);
while ((ok = ref_iterator_advance(iter)) == ITER_OK) {
/*
@@ -1265,54 +1321,6 @@ static int files_pack_refs(struct ref_store *ref_store,
return 0;
}
-static int files_delete_refs(struct ref_store *ref_store, const char *msg,
- struct string_list *refnames, unsigned int flags)
-{
- struct files_ref_store *refs =
- files_downcast(ref_store, REF_STORE_WRITE, "delete_refs");
- struct strbuf err = STRBUF_INIT;
- int i, result = 0;
-
- if (!refnames->nr)
- return 0;
-
- if (packed_refs_lock(refs->packed_ref_store, 0, &err))
- goto error;
-
- if (refs_delete_refs(refs->packed_ref_store, msg, refnames, flags)) {
- packed_refs_unlock(refs->packed_ref_store);
- goto error;
- }
-
- packed_refs_unlock(refs->packed_ref_store);
-
- for (i = 0; i < refnames->nr; i++) {
- const char *refname = refnames->items[i].string;
-
- if (refs_delete_ref(&refs->base, msg, refname, NULL, flags))
- result |= error(_("could not remove reference %s"), refname);
- }
-
- strbuf_release(&err);
- return result;
-
-error:
- /*
- * If we failed to rewrite the packed-refs file, then it is
- * unsafe to try to remove loose refs, because doing so might
- * expose an obsolete packed value for a reference that might
- * even point at an object that has been garbage collected.
- */
- if (refnames->nr == 1)
- error(_("could not delete reference %s: %s"),
- refnames->items[0].string, err.buf);
- else
- error(_("could not delete references: %s"), err.buf);
-
- strbuf_release(&err);
- return -1;
-}
-
/*
* People using contrib's git-new-workdir have .git/logs/refs ->
* /some/other/path/.git/logs/refs, and that may live on another device.
@@ -2166,10 +2174,8 @@ static int files_for_each_reflog_ent(struct ref_store *ref_store,
struct files_reflog_iterator {
struct ref_iterator base;
-
struct ref_store *ref_store;
struct dir_iterator *dir_iterator;
- struct object_id oid;
};
static int files_reflog_iterator_advance(struct ref_iterator *ref_iterator)
@@ -2180,25 +2186,13 @@ static int files_reflog_iterator_advance(struct ref_iterator *ref_iterator)
int ok;
while ((ok = dir_iterator_advance(diter)) == ITER_OK) {
- int flags;
-
if (!S_ISREG(diter->st.st_mode))
continue;
- if (diter->basename[0] == '.')
- continue;
- if (ends_with(diter->basename, ".lock"))
+ if (check_refname_format(diter->basename,
+ REFNAME_ALLOW_ONELEVEL))
continue;
- if (!refs_resolve_ref_unsafe(iter->ref_store,
- diter->relative_path, 0,
- &iter->oid, &flags)) {
- error("bad ref for %s", diter->path.buf);
- continue;
- }
-
iter->base.refname = diter->relative_path;
- iter->base.oid = &iter->oid;
- iter->base.flags = flags;
return ITER_OK;
}
@@ -2243,7 +2237,7 @@ static struct ref_iterator *reflog_iterator_begin(struct ref_store *ref_store,
strbuf_addf(&sb, "%s/logs", gitdir);
- diter = dir_iterator_begin(sb.buf, 0);
+ diter = dir_iterator_begin(sb.buf, DIR_ITERATOR_SORTED);
if (!diter) {
strbuf_release(&sb);
return empty_ref_iterator_begin();
@@ -2252,7 +2246,7 @@ static struct ref_iterator *reflog_iterator_begin(struct ref_store *ref_store,
CALLOC_ARRAY(iter, 1);
ref_iterator = &iter->base;
- base_ref_iterator_init(ref_iterator, &files_reflog_iterator_vtable, 0);
+ base_ref_iterator_init(ref_iterator, &files_reflog_iterator_vtable);
iter->dir_iterator = diter;
iter->ref_store = ref_store;
strbuf_release(&sb);
@@ -2260,32 +2254,6 @@ static struct ref_iterator *reflog_iterator_begin(struct ref_store *ref_store,
return ref_iterator;
}
-static enum iterator_selection reflog_iterator_select(
- struct ref_iterator *iter_worktree,
- struct ref_iterator *iter_common,
- void *cb_data UNUSED)
-{
- if (iter_worktree) {
- /*
- * We're a bit loose here. We probably should ignore
- * common refs if they are accidentally added as
- * per-worktree refs.
- */
- return ITER_SELECT_0;
- } else if (iter_common) {
- if (parse_worktree_ref(iter_common->refname, NULL, NULL,
- NULL) == REF_WORKTREE_SHARED)
- return ITER_SELECT_1;
-
- /*
- * The main ref store may contain main worktree's
- * per-worktree refs, which should be ignored
- */
- return ITER_SKIP_1;
- } else
- return ITER_DONE;
-}
-
static struct ref_iterator *files_reflog_iterator_begin(struct ref_store *ref_store)
{
struct files_ref_store *refs =
@@ -2296,9 +2264,9 @@ static struct ref_iterator *files_reflog_iterator_begin(struct ref_store *ref_st
return reflog_iterator_begin(ref_store, refs->gitcommondir);
} else {
return merge_ref_iterator_begin(
- 0, reflog_iterator_begin(ref_store, refs->base.gitdir),
+ reflog_iterator_begin(ref_store, refs->base.gitdir),
reflog_iterator_begin(ref_store, refs->gitcommondir),
- reflog_iterator_select, refs);
+ ref_iterator_select, refs);
}
}
@@ -3268,28 +3236,52 @@ static int files_reflog_expire(struct ref_store *ref_store,
return -1;
}
-static int files_init_db(struct ref_store *ref_store, struct strbuf *err UNUSED)
+static int files_init_db(struct ref_store *ref_store,
+ int flags,
+ struct strbuf *err UNUSED)
{
struct files_ref_store *refs =
files_downcast(ref_store, REF_STORE_WRITE, "init_db");
struct strbuf sb = STRBUF_INIT;
/*
- * Create .git/refs/{heads,tags}
+ * We need to create a "refs" dir in any case so that older versions of
+ * Git can tell that this is a repository. This serves two main purposes:
+ *
+ * - Clients will know to stop walking the parent-directory chain when
+ * detecting the Git repository. Otherwise they may end up detecting
+ * a Git repository in a parent directory instead.
+ *
+ * - Instead of failing to detect a repository with unknown reference
+ * format altogether, old clients will print an error saying that
+ * they do not understand the reference format extension.
*/
- files_ref_path(refs, &sb, "refs/heads");
+ strbuf_addf(&sb, "%s/refs", ref_store->gitdir);
safe_create_dir(sb.buf, 1);
+ adjust_shared_perm(sb.buf);
- strbuf_reset(&sb);
- files_ref_path(refs, &sb, "refs/tags");
- safe_create_dir(sb.buf, 1);
+ /*
+ * There is no need to create directories for common refs when creating
+ * a worktree ref store.
+ */
+ if (!(flags & REFS_INIT_DB_IS_WORKTREE)) {
+ /*
+ * Create .git/refs/{heads,tags}
+ */
+ strbuf_reset(&sb);
+ files_ref_path(refs, &sb, "refs/heads");
+ safe_create_dir(sb.buf, 1);
+
+ strbuf_reset(&sb);
+ files_ref_path(refs, &sb, "refs/tags");
+ safe_create_dir(sb.buf, 1);
+ }
strbuf_release(&sb);
return 0;
}
struct ref_storage_be refs_be_files = {
- .next = NULL,
.name = "files",
.init = files_ref_store_create,
.init_db = files_init_db,
@@ -3300,7 +3292,6 @@ struct ref_storage_be refs_be_files = {
.pack_refs = files_pack_refs,
.create_symref = files_create_symref,
- .delete_refs = files_delete_refs,
.rename_ref = files_rename_ref,
.copy_ref = files_copy_ref,
diff --git a/refs/iterator.c b/refs/iterator.c
index 6b680f6..9db8b05 100644
--- a/refs/iterator.c
+++ b/refs/iterator.c
@@ -25,11 +25,9 @@ int ref_iterator_abort(struct ref_iterator *ref_iterator)
}
void base_ref_iterator_init(struct ref_iterator *iter,
- struct ref_iterator_vtable *vtable,
- int ordered)
+ struct ref_iterator_vtable *vtable)
{
iter->vtable = vtable;
- iter->ordered = !!ordered;
iter->refname = NULL;
iter->oid = NULL;
iter->flags = 0;
@@ -74,7 +72,7 @@ struct ref_iterator *empty_ref_iterator_begin(void)
struct empty_ref_iterator *iter = xcalloc(1, sizeof(*iter));
struct ref_iterator *ref_iterator = &iter->base;
- base_ref_iterator_init(ref_iterator, &empty_ref_iterator_vtable, 1);
+ base_ref_iterator_init(ref_iterator, &empty_ref_iterator_vtable);
return ref_iterator;
}
@@ -98,6 +96,49 @@ struct merge_ref_iterator {
struct ref_iterator **current;
};
+enum iterator_selection ref_iterator_select(struct ref_iterator *iter_worktree,
+ struct ref_iterator *iter_common,
+ void *cb_data UNUSED)
+{
+ if (iter_worktree && !iter_common) {
+ /*
+ * Return the worktree ref if there are no more common refs.
+ */
+ return ITER_SELECT_0;
+ } else if (iter_common) {
+ /*
+ * In case we have pending worktree and common refs we need to
+ * yield them based on their lexicographical order. Worktree
+ * refs that have the same name as common refs shadow the
+ * latter.
+ */
+ if (iter_worktree) {
+ int cmp = strcmp(iter_worktree->refname,
+ iter_common->refname);
+ if (cmp < 0)
+ return ITER_SELECT_0;
+ else if (!cmp)
+ return ITER_SELECT_0_SKIP_1;
+ }
+
+ /*
+ * We now know that the lexicographically-next ref is a common
+ * ref. When the common ref is a shared one we return it.
+ */
+ if (parse_worktree_ref(iter_common->refname, NULL, NULL,
+ NULL) == REF_WORKTREE_SHARED)
+ return ITER_SELECT_1;
+
+ /*
+ * Otherwise, if the common ref is a per-worktree ref we skip
+ * it because it would belong to the main worktree, not ours.
+ */
+ return ITER_SKIP_1;
+ } else {
+ return ITER_DONE;
+ }
+}
+
static int merge_ref_iterator_advance(struct ref_iterator *ref_iterator)
{
struct merge_ref_iterator *iter =
@@ -207,7 +248,6 @@ static struct ref_iterator_vtable merge_ref_iterator_vtable = {
};
struct ref_iterator *merge_ref_iterator_begin(
- int ordered,
struct ref_iterator *iter0, struct ref_iterator *iter1,
ref_iterator_select_fn *select, void *cb_data)
{
@@ -222,7 +262,7 @@ struct ref_iterator *merge_ref_iterator_begin(
* references through only if they exist in both iterators.
*/
- base_ref_iterator_init(ref_iterator, &merge_ref_iterator_vtable, ordered);
+ base_ref_iterator_init(ref_iterator, &merge_ref_iterator_vtable);
iter->iter0 = iter0;
iter->iter1 = iter1;
iter->select = select;
@@ -271,12 +311,9 @@ struct ref_iterator *overlay_ref_iterator_begin(
} else if (is_empty_ref_iterator(back)) {
ref_iterator_abort(back);
return front;
- } else if (!front->ordered || !back->ordered) {
- BUG("overlay_ref_iterator requires ordered inputs");
}
- return merge_ref_iterator_begin(1, front, back,
- overlay_iterator_select, NULL);
+ return merge_ref_iterator_begin(front, back, overlay_iterator_select, NULL);
}
struct prefix_ref_iterator {
@@ -315,16 +352,12 @@ static int prefix_ref_iterator_advance(struct ref_iterator *ref_iterator)
if (cmp > 0) {
/*
- * If the source iterator is ordered, then we
+ * As the source iterator is ordered, we
* can stop the iteration as soon as we see a
* refname that comes after the prefix:
*/
- if (iter->iter0->ordered) {
- ok = ref_iterator_abort(iter->iter0);
- break;
- } else {
- continue;
- }
+ ok = ref_iterator_abort(iter->iter0);
+ break;
}
if (iter->trim) {
@@ -396,7 +429,7 @@ struct ref_iterator *prefix_ref_iterator_begin(struct ref_iterator *iter0,
CALLOC_ARRAY(iter, 1);
ref_iterator = &iter->base;
- base_ref_iterator_init(ref_iterator, &prefix_ref_iterator_vtable, iter0->ordered);
+ base_ref_iterator_init(ref_iterator, &prefix_ref_iterator_vtable);
iter->iter0 = iter0;
iter->prefix = xstrdup(prefix);
diff --git a/refs/packed-backend.c b/refs/packed-backend.c
index 59c78d7..4e826c0 100644
--- a/refs/packed-backend.c
+++ b/refs/packed-backend.c
@@ -1,5 +1,4 @@
#include "../git-compat-util.h"
-#include "../alloc.h"
#include "../config.h"
#include "../gettext.h"
#include "../hash.h"
@@ -1112,7 +1111,7 @@ static struct ref_iterator *packed_ref_iterator_begin(
CALLOC_ARRAY(iter, 1);
ref_iterator = &iter->base;
- base_ref_iterator_init(ref_iterator, &packed_ref_iterator_vtable, 1);
+ base_ref_iterator_init(ref_iterator, &packed_ref_iterator_vtable);
if (exclude_patterns)
populate_excluded_jump_list(iter, snapshot, exclude_patterns);
@@ -1246,6 +1245,7 @@ static const char PACKED_REFS_HEADER[] =
"# pack-refs with: peeled fully-peeled sorted \n";
static int packed_init_db(struct ref_store *ref_store UNUSED,
+ int flags UNUSED,
struct strbuf *err UNUSED)
{
/* Nothing to do. */
@@ -1688,55 +1688,6 @@ static int packed_initial_transaction_commit(struct ref_store *ref_store UNUSED,
return ref_transaction_commit(transaction, err);
}
-static int packed_delete_refs(struct ref_store *ref_store, const char *msg,
- struct string_list *refnames, unsigned int flags)
-{
- struct packed_ref_store *refs =
- packed_downcast(ref_store, REF_STORE_WRITE, "delete_refs");
- struct strbuf err = STRBUF_INIT;
- struct ref_transaction *transaction;
- struct string_list_item *item;
- int ret;
-
- (void)refs; /* We need the check above, but don't use the variable */
-
- if (!refnames->nr)
- return 0;
-
- /*
- * Since we don't check the references' old_oids, the
- * individual updates can't fail, so we can pack all of the
- * updates into a single transaction.
- */
-
- transaction = ref_store_transaction_begin(ref_store, &err);
- if (!transaction)
- return -1;
-
- for_each_string_list_item(item, refnames) {
- if (ref_transaction_delete(transaction, item->string, NULL,
- flags, msg, &err)) {
- warning(_("could not delete reference %s: %s"),
- item->string, err.buf);
- strbuf_reset(&err);
- }
- }
-
- ret = ref_transaction_commit(transaction, &err);
-
- if (ret) {
- if (refnames->nr == 1)
- error(_("could not delete reference %s: %s"),
- refnames->items[0].string, err.buf);
- else
- error(_("could not delete references: %s"), err.buf);
- }
-
- ref_transaction_free(transaction);
- strbuf_release(&err);
- return ret;
-}
-
static int packed_pack_refs(struct ref_store *ref_store UNUSED,
struct pack_refs_opts *pack_opts UNUSED)
{
@@ -1754,7 +1705,6 @@ static struct ref_iterator *packed_reflog_iterator_begin(struct ref_store *ref_s
}
struct ref_storage_be refs_be_packed = {
- .next = NULL,
.name = "packed",
.init = packed_ref_store_create,
.init_db = packed_init_db,
@@ -1765,7 +1715,6 @@ struct ref_storage_be refs_be_packed = {
.pack_refs = packed_pack_refs,
.create_symref = NULL,
- .delete_refs = packed_delete_refs,
.rename_ref = NULL,
.copy_ref = NULL,
diff --git a/refs/ref-cache.c b/refs/ref-cache.c
index 6e3b725..9f97972 100644
--- a/refs/ref-cache.c
+++ b/refs/ref-cache.c
@@ -1,5 +1,4 @@
#include "../git-compat-util.h"
-#include "../alloc.h"
#include "../hash.h"
#include "../refs.h"
#include "../repository.h"
@@ -487,7 +486,7 @@ struct ref_iterator *cache_ref_iterator_begin(struct ref_cache *cache,
CALLOC_ARRAY(iter, 1);
ref_iterator = &iter->base;
- base_ref_iterator_init(ref_iterator, &cache_ref_iterator_vtable, 1);
+ base_ref_iterator_init(ref_iterator, &cache_ref_iterator_vtable);
ALLOC_GROW(iter->levels, 10, iter->levels_alloc);
iter->levels_nr = 1;
diff --git a/refs/refs-internal.h b/refs/refs-internal.h
index 9db8aec..56641aa 100644
--- a/refs/refs-internal.h
+++ b/refs/refs-internal.h
@@ -260,6 +260,12 @@ enum do_for_each_ref_flags {
* INCLUDE_BROKEN, since they are otherwise not included at all.
*/
DO_FOR_EACH_OMIT_DANGLING_SYMREFS = (1 << 2),
+
+ /*
+ * Include root refs i.e. HEAD and pseudorefs along with the regular
+ * refs.
+ */
+ DO_FOR_EACH_INCLUDE_ROOT_REFS = (1 << 3),
};
/*
@@ -312,13 +318,6 @@ enum do_for_each_ref_flags {
*/
struct ref_iterator {
struct ref_iterator_vtable *vtable;
-
- /*
- * Does this `ref_iterator` iterate over references in order
- * by refname?
- */
- unsigned int ordered : 1;
-
const char *refname;
const struct object_id *oid;
unsigned int flags;
@@ -387,14 +386,21 @@ typedef enum iterator_selection ref_iterator_select_fn(
void *cb_data);
/*
+ * An implementation of ref_iterator_select_fn that merges worktree and common
+ * refs. Per-worktree refs from the common iterator are ignored, worktree refs
+ * override common refs. Refs are selected lexicographically.
+ */
+enum iterator_selection ref_iterator_select(struct ref_iterator *iter_worktree,
+ struct ref_iterator *iter_common,
+ void *cb_data);
+
+/*
* Iterate over the entries from iter0 and iter1, with the values
* interleaved as directed by the select function. The iterator takes
* ownership of iter0 and iter1 and frees them when the iteration is
- * over. A derived class should set `ordered` to 1 or 0 based on
- * whether it generates its output in order by reference name.
+ * over.
*/
struct ref_iterator *merge_ref_iterator_begin(
- int ordered,
struct ref_iterator *iter0, struct ref_iterator *iter1,
ref_iterator_select_fn *select, void *cb_data);
@@ -423,8 +429,6 @@ struct ref_iterator *overlay_ref_iterator_begin(
* As an convenience to callers, if prefix is the empty string and
* trim is zero, this function returns iter0 directly, without
* wrapping it.
- *
- * The resulting ref_iterator is ordered if iter0 is.
*/
struct ref_iterator *prefix_ref_iterator_begin(struct ref_iterator *iter0,
const char *prefix,
@@ -435,14 +439,11 @@ struct ref_iterator *prefix_ref_iterator_begin(struct ref_iterator *iter0,
/*
* Base class constructor for ref_iterators. Initialize the
* ref_iterator part of iter, setting its vtable pointer as specified.
- * `ordered` should be set to 1 if the iterator will iterate over
- * references in order by refname; otherwise it should be set to 0.
* This is meant to be called only by the initializers of derived
* classes.
*/
void base_ref_iterator_init(struct ref_iterator *iter,
- struct ref_iterator_vtable *vtable,
- int ordered);
+ struct ref_iterator_vtable *vtable);
/*
* Base class destructor for ref_iterators. Destroy the ref_iterator
@@ -529,7 +530,9 @@ typedef struct ref_store *ref_store_init_fn(struct repository *repo,
const char *gitdir,
unsigned int flags);
-typedef int ref_init_db_fn(struct ref_store *refs, struct strbuf *err);
+typedef int ref_init_db_fn(struct ref_store *refs,
+ int flags,
+ struct strbuf *err);
typedef int ref_transaction_prepare_fn(struct ref_store *refs,
struct ref_transaction *transaction,
@@ -553,8 +556,6 @@ typedef int create_symref_fn(struct ref_store *ref_store,
const char *ref_target,
const char *refs_heads_master,
const char *logmsg);
-typedef int delete_refs_fn(struct ref_store *ref_store, const char *msg,
- struct string_list *refnames, unsigned int flags);
typedef int rename_ref_fn(struct ref_store *ref_store,
const char *oldref, const char *newref,
const char *logmsg);
@@ -665,7 +666,6 @@ typedef int read_symbolic_ref_fn(struct ref_store *ref_store, const char *refnam
struct strbuf *referent);
struct ref_storage_be {
- struct ref_storage_be *next;
const char *name;
ref_store_init_fn *init;
ref_init_db_fn *init_db;
@@ -677,7 +677,6 @@ struct ref_storage_be {
pack_refs_fn *pack_refs;
create_symref_fn *create_symref;
- delete_refs_fn *delete_refs;
rename_ref_fn *rename_ref;
copy_ref_fn *copy_ref;
@@ -695,6 +694,7 @@ struct ref_storage_be {
};
extern struct ref_storage_be refs_be_files;
+extern struct ref_storage_be refs_be_reftable;
extern struct ref_storage_be refs_be_packed;
/*
diff --git a/refs/reftable-backend.c b/refs/reftable-backend.c
new file mode 100644
index 0000000..1cda48c
--- /dev/null
+++ b/refs/reftable-backend.c
@@ -0,0 +1,2242 @@
+#include "../git-compat-util.h"
+#include "../abspath.h"
+#include "../chdir-notify.h"
+#include "../environment.h"
+#include "../gettext.h"
+#include "../hash.h"
+#include "../hex.h"
+#include "../iterator.h"
+#include "../ident.h"
+#include "../lockfile.h"
+#include "../object.h"
+#include "../path.h"
+#include "../refs.h"
+#include "../reftable/reftable-stack.h"
+#include "../reftable/reftable-record.h"
+#include "../reftable/reftable-error.h"
+#include "../reftable/reftable-iterator.h"
+#include "../reftable/reftable-merged.h"
+#include "../setup.h"
+#include "../strmap.h"
+#include "parse.h"
+#include "refs-internal.h"
+
+/*
+ * Used as a flag in ref_update::flags when the ref_update was via an
+ * update to HEAD.
+ */
+#define REF_UPDATE_VIA_HEAD (1 << 8)
+
+struct reftable_ref_store {
+ struct ref_store base;
+
+ /*
+ * The main stack refers to the common dir and thus contains common
+ * refs as well as refs of the main repository.
+ */
+ struct reftable_stack *main_stack;
+ /*
+ * The worktree stack refers to the gitdir in case the refdb is opened
+ * via a worktree. It thus contains the per-worktree refs.
+ */
+ struct reftable_stack *worktree_stack;
+ /*
+ * Map of worktree stacks by their respective worktree names. The map
+ * is populated lazily when we try to resolve `worktrees/$worktree` refs.
+ */
+ struct strmap worktree_stacks;
+ struct reftable_write_options write_options;
+
+ unsigned int store_flags;
+ int err;
+};
+
+/*
+ * Downcast ref_store to reftable_ref_store. Die if ref_store is not a
+ * reftable_ref_store. required_flags is compared with ref_store's store_flags
+ * to ensure the ref_store has all required capabilities. "caller" is used in
+ * any necessary error messages.
+ */
+static struct reftable_ref_store *reftable_be_downcast(struct ref_store *ref_store,
+ unsigned int required_flags,
+ const char *caller)
+{
+ struct reftable_ref_store *refs;
+
+ if (ref_store->be != &refs_be_reftable)
+ BUG("ref_store is type \"%s\" not \"reftables\" in %s",
+ ref_store->be->name, caller);
+
+ refs = (struct reftable_ref_store *)ref_store;
+
+ if ((refs->store_flags & required_flags) != required_flags)
+ BUG("operation %s requires abilities 0x%x, but only have 0x%x",
+ caller, required_flags, refs->store_flags);
+
+ return refs;
+}
+
+/*
+ * Some refs are global to the repository (refs/heads/{*}), while others are
+ * local to the worktree (eg. HEAD, refs/bisect/{*}). We solve this by having
+ * multiple separate databases (ie. multiple reftable/ directories), one for
+ * the shared refs, one for the current worktree refs, and one for each
+ * additional worktree. For reading, we merge the view of both the shared and
+ * the current worktree's refs, when necessary.
+ *
+ * This function also optionally assigns the rewritten reference name that is
+ * local to the stack. This translation is required when using worktree refs
+ * like `worktrees/$worktree/refs/heads/foo` as worktree stacks will store
+ * those references in their normalized form.
+ */
+static struct reftable_stack *stack_for(struct reftable_ref_store *store,
+ const char *refname,
+ const char **rewritten_ref)
+{
+ const char *wtname;
+ int wtname_len;
+
+ if (!refname)
+ return store->main_stack;
+
+ switch (parse_worktree_ref(refname, &wtname, &wtname_len, rewritten_ref)) {
+ case REF_WORKTREE_OTHER: {
+ static struct strbuf wtname_buf = STRBUF_INIT;
+ struct strbuf wt_dir = STRBUF_INIT;
+ struct reftable_stack *stack;
+
+ /*
+ * We're using a static buffer here so that we don't need to
+ * allocate the worktree name whenever we look up a reference.
+ * This could be avoided if the strmap interface knew how to
+ * handle keys with a length.
+ */
+ strbuf_reset(&wtname_buf);
+ strbuf_add(&wtname_buf, wtname, wtname_len);
+
+ /*
+ * There is an edge case here: when the worktree references the
+ * current worktree, then we set up the stack once via
+ * `worktree_stacks` and once via `worktree_stack`. This is
+ * wasteful, but in the reading case it shouldn't matter. And
+ * in the writing case we would notice that the stack is locked
+ * already and error out when trying to write a reference via
+ * both stacks.
+ */
+ stack = strmap_get(&store->worktree_stacks, wtname_buf.buf);
+ if (!stack) {
+ strbuf_addf(&wt_dir, "%s/worktrees/%s/reftable",
+ store->base.repo->commondir, wtname_buf.buf);
+
+ store->err = reftable_new_stack(&stack, wt_dir.buf,
+ store->write_options);
+ assert(store->err != REFTABLE_API_ERROR);
+ strmap_put(&store->worktree_stacks, wtname_buf.buf, stack);
+ }
+
+ strbuf_release(&wt_dir);
+ return stack;
+ }
+ case REF_WORKTREE_CURRENT:
+ /*
+ * If there is no worktree stack then we're currently in the
+ * main worktree. We thus return the main stack in that case.
+ */
+ if (!store->worktree_stack)
+ return store->main_stack;
+ return store->worktree_stack;
+ case REF_WORKTREE_MAIN:
+ case REF_WORKTREE_SHARED:
+ return store->main_stack;
+ default:
+ BUG("unhandled worktree reference type");
+ }
+}
+
+static int should_write_log(struct ref_store *refs, const char *refname)
+{
+ if (log_all_ref_updates == LOG_REFS_UNSET)
+ log_all_ref_updates = is_bare_repository() ? LOG_REFS_NONE : LOG_REFS_NORMAL;
+
+ switch (log_all_ref_updates) {
+ case LOG_REFS_NONE:
+ return refs_reflog_exists(refs, refname);
+ case LOG_REFS_ALWAYS:
+ return 1;
+ case LOG_REFS_NORMAL:
+ if (should_autocreate_reflog(refname))
+ return 1;
+ return refs_reflog_exists(refs, refname);
+ default:
+ BUG("unhandled core.logAllRefUpdates value %d", log_all_ref_updates);
+ }
+}
+
+static void fill_reftable_log_record(struct reftable_log_record *log)
+{
+ const char *info = git_committer_info(0);
+ struct ident_split split = {0};
+ int sign = 1;
+
+ if (split_ident_line(&split, info, strlen(info)))
+ BUG("failed splitting committer info");
+
+ reftable_log_record_release(log);
+ log->value_type = REFTABLE_LOG_UPDATE;
+ log->value.update.name =
+ xstrndup(split.name_begin, split.name_end - split.name_begin);
+ log->value.update.email =
+ xstrndup(split.mail_begin, split.mail_end - split.mail_begin);
+ log->value.update.time = atol(split.date_begin);
+ if (*split.tz_begin == '-') {
+ sign = -1;
+ split.tz_begin++;
+ }
+ if (*split.tz_begin == '+') {
+ sign = 1;
+ split.tz_begin++;
+ }
+
+ log->value.update.tz_offset = sign * atoi(split.tz_begin);
+}
+
+static int read_ref_without_reload(struct reftable_stack *stack,
+ const char *refname,
+ struct object_id *oid,
+ struct strbuf *referent,
+ unsigned int *type)
+{
+ struct reftable_ref_record ref = {0};
+ int ret;
+
+ ret = reftable_stack_read_ref(stack, refname, &ref);
+ if (ret)
+ goto done;
+
+ if (ref.value_type == REFTABLE_REF_SYMREF) {
+ strbuf_reset(referent);
+ strbuf_addstr(referent, ref.value.symref);
+ *type |= REF_ISSYMREF;
+ } else if (reftable_ref_record_val1(&ref)) {
+ oidread(oid, reftable_ref_record_val1(&ref));
+ } else {
+ /* We got a tombstone, which should not happen. */
+ BUG("unhandled reference value type %d", ref.value_type);
+ }
+
+done:
+ assert(ret != REFTABLE_API_ERROR);
+ reftable_ref_record_release(&ref);
+ return ret;
+}
+
+static struct ref_store *reftable_be_init(struct repository *repo,
+ const char *gitdir,
+ unsigned int store_flags)
+{
+ struct reftable_ref_store *refs = xcalloc(1, sizeof(*refs));
+ struct strbuf path = STRBUF_INIT;
+ int is_worktree;
+ mode_t mask;
+
+ mask = umask(0);
+ umask(mask);
+
+ base_ref_store_init(&refs->base, repo, gitdir, &refs_be_reftable);
+ strmap_init(&refs->worktree_stacks);
+ refs->store_flags = store_flags;
+ refs->write_options.block_size = 4096;
+ refs->write_options.hash_id = repo->hash_algo->format_id;
+ refs->write_options.default_permissions = calc_shared_perm(0666 & ~mask);
+ refs->write_options.disable_auto_compact =
+ !git_env_bool("GIT_TEST_REFTABLE_AUTOCOMPACTION", 1);
+
+ /*
+ * Set up the main reftable stack that is hosted in GIT_COMMON_DIR.
+ * This stack contains both the shared and the main worktree refs.
+ *
+ * Note that we don't try to resolve the path in case we have a
+ * worktree because `get_common_dir_noenv()` already does it for us.
+ */
+ is_worktree = get_common_dir_noenv(&path, gitdir);
+ if (!is_worktree) {
+ strbuf_reset(&path);
+ strbuf_realpath(&path, gitdir, 0);
+ }
+ strbuf_addstr(&path, "/reftable");
+ refs->err = reftable_new_stack(&refs->main_stack, path.buf,
+ refs->write_options);
+ if (refs->err)
+ goto done;
+
+ /*
+ * If we're in a worktree we also need to set up the worktree reftable
+ * stack that is contained in the per-worktree GIT_DIR.
+ *
+ * Ideally, we would also add the stack to our worktree stack map. But
+ * we have no way to figure out the worktree name here and thus can't
+ * do it efficiently.
+ */
+ if (is_worktree) {
+ strbuf_reset(&path);
+ strbuf_addf(&path, "%s/reftable", gitdir);
+
+ refs->err = reftable_new_stack(&refs->worktree_stack, path.buf,
+ refs->write_options);
+ if (refs->err)
+ goto done;
+ }
+
+ chdir_notify_reparent("reftables-backend $GIT_DIR", &refs->base.gitdir);
+
+done:
+ assert(refs->err != REFTABLE_API_ERROR);
+ strbuf_release(&path);
+ return &refs->base;
+}
+
+static int reftable_be_init_db(struct ref_store *ref_store,
+ int flags UNUSED,
+ struct strbuf *err UNUSED)
+{
+ struct reftable_ref_store *refs =
+ reftable_be_downcast(ref_store, REF_STORE_WRITE, "init_db");
+ struct strbuf sb = STRBUF_INIT;
+
+ strbuf_addf(&sb, "%s/reftable", refs->base.gitdir);
+ safe_create_dir(sb.buf, 1);
+ strbuf_reset(&sb);
+
+ strbuf_addf(&sb, "%s/HEAD", refs->base.gitdir);
+ write_file(sb.buf, "ref: refs/heads/.invalid");
+ adjust_shared_perm(sb.buf);
+ strbuf_reset(&sb);
+
+ strbuf_addf(&sb, "%s/refs", refs->base.gitdir);
+ safe_create_dir(sb.buf, 1);
+ strbuf_reset(&sb);
+
+ strbuf_addf(&sb, "%s/refs/heads", refs->base.gitdir);
+ write_file(sb.buf, "this repository uses the reftable format");
+ adjust_shared_perm(sb.buf);
+
+ strbuf_release(&sb);
+ return 0;
+}
+
+struct reftable_ref_iterator {
+ struct ref_iterator base;
+ struct reftable_ref_store *refs;
+ struct reftable_iterator iter;
+ struct reftable_ref_record ref;
+ struct object_id oid;
+
+ const char *prefix;
+ size_t prefix_len;
+ unsigned int flags;
+ int err;
+};
+
+static int reftable_ref_iterator_advance(struct ref_iterator *ref_iterator)
+{
+ struct reftable_ref_iterator *iter =
+ (struct reftable_ref_iterator *)ref_iterator;
+ struct reftable_ref_store *refs = iter->refs;
+
+ while (!iter->err) {
+ int flags = 0;
+
+ iter->err = reftable_iterator_next_ref(&iter->iter, &iter->ref);
+ if (iter->err)
+ break;
+
+ /*
+ * The files backend only lists references contained in "refs/" unless
+ * the root refs are to be included. We emulate the same behaviour here.
+ */
+ if (!starts_with(iter->ref.refname, "refs/") &&
+ !(iter->flags & DO_FOR_EACH_INCLUDE_ROOT_REFS &&
+ (is_pseudoref(&iter->refs->base, iter->ref.refname) ||
+ is_headref(&iter->refs->base, iter->ref.refname)))) {
+ continue;
+ }
+
+ if (iter->prefix_len &&
+ strncmp(iter->prefix, iter->ref.refname, iter->prefix_len)) {
+ iter->err = 1;
+ break;
+ }
+
+ if (iter->flags & DO_FOR_EACH_PER_WORKTREE_ONLY &&
+ parse_worktree_ref(iter->ref.refname, NULL, NULL, NULL) !=
+ REF_WORKTREE_CURRENT)
+ continue;
+
+ switch (iter->ref.value_type) {
+ case REFTABLE_REF_VAL1:
+ oidread(&iter->oid, iter->ref.value.val1);
+ break;
+ case REFTABLE_REF_VAL2:
+ oidread(&iter->oid, iter->ref.value.val2.value);
+ break;
+ case REFTABLE_REF_SYMREF:
+ if (!refs_resolve_ref_unsafe(&iter->refs->base, iter->ref.refname,
+ RESOLVE_REF_READING, &iter->oid, &flags))
+ oidclr(&iter->oid);
+ break;
+ default:
+ BUG("unhandled reference value type %d", iter->ref.value_type);
+ }
+
+ if (is_null_oid(&iter->oid))
+ flags |= REF_ISBROKEN;
+
+ if (check_refname_format(iter->ref.refname, REFNAME_ALLOW_ONELEVEL)) {
+ if (!refname_is_safe(iter->ref.refname))
+ die(_("refname is dangerous: %s"), iter->ref.refname);
+ oidclr(&iter->oid);
+ flags |= REF_BAD_NAME | REF_ISBROKEN;
+ }
+
+ if (iter->flags & DO_FOR_EACH_OMIT_DANGLING_SYMREFS &&
+ flags & REF_ISSYMREF &&
+ flags & REF_ISBROKEN)
+ continue;
+
+ if (!(iter->flags & DO_FOR_EACH_INCLUDE_BROKEN) &&
+ !ref_resolves_to_object(iter->ref.refname, refs->base.repo,
+ &iter->oid, flags))
+ continue;
+
+ iter->base.refname = iter->ref.refname;
+ iter->base.oid = &iter->oid;
+ iter->base.flags = flags;
+
+ break;
+ }
+
+ if (iter->err > 0) {
+ if (ref_iterator_abort(ref_iterator) != ITER_DONE)
+ return ITER_ERROR;
+ return ITER_DONE;
+ }
+
+ if (iter->err < 0) {
+ ref_iterator_abort(ref_iterator);
+ return ITER_ERROR;
+ }
+
+ return ITER_OK;
+}
+
+static int reftable_ref_iterator_peel(struct ref_iterator *ref_iterator,
+ struct object_id *peeled)
+{
+ struct reftable_ref_iterator *iter =
+ (struct reftable_ref_iterator *)ref_iterator;
+
+ if (iter->ref.value_type == REFTABLE_REF_VAL2) {
+ oidread(peeled, iter->ref.value.val2.target_value);
+ return 0;
+ }
+
+ return -1;
+}
+
+static int reftable_ref_iterator_abort(struct ref_iterator *ref_iterator)
+{
+ struct reftable_ref_iterator *iter =
+ (struct reftable_ref_iterator *)ref_iterator;
+ reftable_ref_record_release(&iter->ref);
+ reftable_iterator_destroy(&iter->iter);
+ free(iter);
+ return ITER_DONE;
+}
+
+static struct ref_iterator_vtable reftable_ref_iterator_vtable = {
+ .advance = reftable_ref_iterator_advance,
+ .peel = reftable_ref_iterator_peel,
+ .abort = reftable_ref_iterator_abort
+};
+
+static struct reftable_ref_iterator *ref_iterator_for_stack(struct reftable_ref_store *refs,
+ struct reftable_stack *stack,
+ const char *prefix,
+ int flags)
+{
+ struct reftable_merged_table *merged_table;
+ struct reftable_ref_iterator *iter;
+ int ret;
+
+ iter = xcalloc(1, sizeof(*iter));
+ base_ref_iterator_init(&iter->base, &reftable_ref_iterator_vtable);
+ iter->prefix = prefix;
+ iter->prefix_len = prefix ? strlen(prefix) : 0;
+ iter->base.oid = &iter->oid;
+ iter->flags = flags;
+ iter->refs = refs;
+
+ ret = refs->err;
+ if (ret)
+ goto done;
+
+ ret = reftable_stack_reload(stack);
+ if (ret)
+ goto done;
+
+ merged_table = reftable_stack_merged_table(stack);
+
+ ret = reftable_merged_table_seek_ref(merged_table, &iter->iter, prefix);
+ if (ret)
+ goto done;
+
+done:
+ iter->err = ret;
+ return iter;
+}
+
+static struct ref_iterator *reftable_be_iterator_begin(struct ref_store *ref_store,
+ const char *prefix,
+ const char **exclude_patterns,
+ unsigned int flags)
+{
+ struct reftable_ref_iterator *main_iter, *worktree_iter;
+ struct reftable_ref_store *refs;
+ unsigned int required_flags = REF_STORE_READ;
+
+ if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN))
+ required_flags |= REF_STORE_ODB;
+ refs = reftable_be_downcast(ref_store, required_flags, "ref_iterator_begin");
+
+ main_iter = ref_iterator_for_stack(refs, refs->main_stack, prefix, flags);
+
+ /*
+ * The worktree stack is only set when we're in an actual worktree
+ * right now. If we aren't, then we return the common reftable
+ * iterator, only.
+ */
+ if (!refs->worktree_stack)
+ return &main_iter->base;
+
+ /*
+ * Otherwise we merge both the common and the per-worktree refs into a
+ * single iterator.
+ */
+ worktree_iter = ref_iterator_for_stack(refs, refs->worktree_stack, prefix, flags);
+ return merge_ref_iterator_begin(&worktree_iter->base, &main_iter->base,
+ ref_iterator_select, NULL);
+}
+
+static int reftable_be_read_raw_ref(struct ref_store *ref_store,
+ const char *refname,
+ struct object_id *oid,
+ struct strbuf *referent,
+ unsigned int *type,
+ int *failure_errno)
+{
+ struct reftable_ref_store *refs =
+ reftable_be_downcast(ref_store, REF_STORE_READ, "read_raw_ref");
+ struct reftable_stack *stack = stack_for(refs, refname, &refname);
+ int ret;
+
+ if (refs->err < 0)
+ return refs->err;
+
+ ret = reftable_stack_reload(stack);
+ if (ret)
+ return ret;
+
+ ret = read_ref_without_reload(stack, refname, oid, referent, type);
+ if (ret < 0)
+ return ret;
+ if (ret > 0) {
+ *failure_errno = ENOENT;
+ return -1;
+ }
+
+ return 0;
+}
+
+static int reftable_be_read_symbolic_ref(struct ref_store *ref_store,
+ const char *refname,
+ struct strbuf *referent)
+{
+ struct reftable_ref_store *refs =
+ reftable_be_downcast(ref_store, REF_STORE_READ, "read_symbolic_ref");
+ struct reftable_stack *stack = stack_for(refs, refname, &refname);
+ struct reftable_ref_record ref = {0};
+ int ret;
+
+ ret = reftable_stack_reload(stack);
+ if (ret)
+ return ret;
+
+ ret = reftable_stack_read_ref(stack, refname, &ref);
+ if (ret == 0 && ref.value_type == REFTABLE_REF_SYMREF)
+ strbuf_addstr(referent, ref.value.symref);
+ else
+ ret = -1;
+
+ reftable_ref_record_release(&ref);
+ return ret;
+}
+
+/*
+ * Return the refname under which update was originally requested.
+ */
+static const char *original_update_refname(struct ref_update *update)
+{
+ while (update->parent_update)
+ update = update->parent_update;
+ return update->refname;
+}
+
+struct reftable_transaction_update {
+ struct ref_update *update;
+ struct object_id current_oid;
+};
+
+struct write_transaction_table_arg {
+ struct reftable_ref_store *refs;
+ struct reftable_stack *stack;
+ struct reftable_addition *addition;
+ struct reftable_transaction_update *updates;
+ size_t updates_nr;
+ size_t updates_alloc;
+ size_t updates_expected;
+};
+
+struct reftable_transaction_data {
+ struct write_transaction_table_arg *args;
+ size_t args_nr, args_alloc;
+};
+
+static void free_transaction_data(struct reftable_transaction_data *tx_data)
+{
+ if (!tx_data)
+ return;
+ for (size_t i = 0; i < tx_data->args_nr; i++) {
+ reftable_addition_destroy(tx_data->args[i].addition);
+ free(tx_data->args[i].updates);
+ }
+ free(tx_data->args);
+ free(tx_data);
+}
+
+/*
+ * Prepare transaction update for the given reference update. This will cause
+ * us to lock the corresponding reftable stack for concurrent modification.
+ */
+static int prepare_transaction_update(struct write_transaction_table_arg **out,
+ struct reftable_ref_store *refs,
+ struct reftable_transaction_data *tx_data,
+ struct ref_update *update,
+ struct strbuf *err)
+{
+ struct reftable_stack *stack = stack_for(refs, update->refname, NULL);
+ struct write_transaction_table_arg *arg = NULL;
+ size_t i;
+ int ret;
+
+ /*
+ * Search for a preexisting stack update. If there is one then we add
+ * the update to it, otherwise we set up a new stack update.
+ */
+ for (i = 0; !arg && i < tx_data->args_nr; i++)
+ if (tx_data->args[i].stack == stack)
+ arg = &tx_data->args[i];
+
+ if (!arg) {
+ struct reftable_addition *addition;
+
+ ret = reftable_stack_reload(stack);
+ if (ret)
+ return ret;
+
+ ret = reftable_stack_new_addition(&addition, stack);
+ if (ret) {
+ if (ret == REFTABLE_LOCK_ERROR)
+ strbuf_addstr(err, "cannot lock references");
+ return ret;
+ }
+
+ ALLOC_GROW(tx_data->args, tx_data->args_nr + 1,
+ tx_data->args_alloc);
+ arg = &tx_data->args[tx_data->args_nr++];
+ arg->refs = refs;
+ arg->stack = stack;
+ arg->addition = addition;
+ arg->updates = NULL;
+ arg->updates_nr = 0;
+ arg->updates_alloc = 0;
+ arg->updates_expected = 0;
+ }
+
+ arg->updates_expected++;
+
+ if (out)
+ *out = arg;
+
+ return 0;
+}
+
+/*
+ * Queue a reference update for the correct stack. We potentially need to
+ * handle multiple stack updates in a single transaction when it spans across
+ * multiple worktrees.
+ */
+static int queue_transaction_update(struct reftable_ref_store *refs,
+ struct reftable_transaction_data *tx_data,
+ struct ref_update *update,
+ struct object_id *current_oid,
+ struct strbuf *err)
+{
+ struct write_transaction_table_arg *arg = NULL;
+ int ret;
+
+ if (update->backend_data)
+ BUG("reference update queued more than once");
+
+ ret = prepare_transaction_update(&arg, refs, tx_data, update, err);
+ if (ret < 0)
+ return ret;
+
+ ALLOC_GROW(arg->updates, arg->updates_nr + 1,
+ arg->updates_alloc);
+ arg->updates[arg->updates_nr].update = update;
+ oidcpy(&arg->updates[arg->updates_nr].current_oid, current_oid);
+ update->backend_data = &arg->updates[arg->updates_nr++];
+
+ return 0;
+}
+
+static int reftable_be_transaction_prepare(struct ref_store *ref_store,
+ struct ref_transaction *transaction,
+ struct strbuf *err)
+{
+ struct reftable_ref_store *refs =
+ reftable_be_downcast(ref_store, REF_STORE_WRITE|REF_STORE_MAIN, "ref_transaction_prepare");
+ struct strbuf referent = STRBUF_INIT, head_referent = STRBUF_INIT;
+ struct string_list affected_refnames = STRING_LIST_INIT_NODUP;
+ struct reftable_transaction_data *tx_data = NULL;
+ struct object_id head_oid;
+ unsigned int head_type = 0;
+ size_t i;
+ int ret;
+
+ ret = refs->err;
+ if (ret < 0)
+ goto done;
+
+ tx_data = xcalloc(1, sizeof(*tx_data));
+
+ /*
+ * Preprocess all updates. For one we check that there are no duplicate
+ * reference updates in this transaction. Second, we lock all stacks
+ * that will be modified during the transaction.
+ */
+ for (i = 0; i < transaction->nr; i++) {
+ ret = prepare_transaction_update(NULL, refs, tx_data,
+ transaction->updates[i], err);
+ if (ret)
+ goto done;
+
+ string_list_append(&affected_refnames,
+ transaction->updates[i]->refname);
+ }
+
+ /*
+ * Now that we have counted updates per stack we can preallocate their
+ * arrays. This avoids having to reallocate many times.
+ */
+ for (i = 0; i < tx_data->args_nr; i++) {
+ CALLOC_ARRAY(tx_data->args[i].updates, tx_data->args[i].updates_expected);
+ tx_data->args[i].updates_alloc = tx_data->args[i].updates_expected;
+ }
+
+ /*
+ * Fail if a refname appears more than once in the transaction.
+ * This code is taken from the files backend and is a good candidate to
+ * be moved into the generic layer.
+ */
+ string_list_sort(&affected_refnames);
+ if (ref_update_reject_duplicates(&affected_refnames, err)) {
+ ret = TRANSACTION_GENERIC_ERROR;
+ goto done;
+ }
+
+ ret = read_ref_without_reload(stack_for(refs, "HEAD", NULL), "HEAD", &head_oid,
+ &head_referent, &head_type);
+ if (ret < 0)
+ goto done;
+ ret = 0;
+
+ for (i = 0; i < transaction->nr; i++) {
+ struct ref_update *u = transaction->updates[i];
+ struct object_id current_oid = {0};
+ struct reftable_stack *stack;
+ const char *rewritten_ref;
+
+ stack = stack_for(refs, u->refname, &rewritten_ref);
+
+ /* Verify that the new object ID is valid. */
+ if ((u->flags & REF_HAVE_NEW) && !is_null_oid(&u->new_oid) &&
+ !(u->flags & REF_SKIP_OID_VERIFICATION) &&
+ !(u->flags & REF_LOG_ONLY)) {
+ struct object *o = parse_object(refs->base.repo, &u->new_oid);
+ if (!o) {
+ strbuf_addf(err,
+ _("trying to write ref '%s' with nonexistent object %s"),
+ u->refname, oid_to_hex(&u->new_oid));
+ ret = -1;
+ goto done;
+ }
+
+ if (o->type != OBJ_COMMIT && is_branch(u->refname)) {
+ strbuf_addf(err, _("trying to write non-commit object %s to branch '%s'"),
+ oid_to_hex(&u->new_oid), u->refname);
+ ret = -1;
+ goto done;
+ }
+ }
+
+ /*
+ * When we update the reference that HEAD points to we enqueue
+ * a second log-only update for HEAD so that its reflog is
+ * updated accordingly.
+ */
+ if (head_type == REF_ISSYMREF &&
+ !(u->flags & REF_LOG_ONLY) &&
+ !(u->flags & REF_UPDATE_VIA_HEAD) &&
+ !strcmp(rewritten_ref, head_referent.buf)) {
+ struct ref_update *new_update;
+
+ /*
+ * First make sure that HEAD is not already in the
+ * transaction. This check is O(lg N) in the transaction
+ * size, but it happens at most once per transaction.
+ */
+ if (string_list_has_string(&affected_refnames, "HEAD")) {
+ /* An entry already existed */
+ strbuf_addf(err,
+ _("multiple updates for 'HEAD' (including one "
+ "via its referent '%s') are not allowed"),
+ u->refname);
+ ret = TRANSACTION_NAME_CONFLICT;
+ goto done;
+ }
+
+ new_update = ref_transaction_add_update(
+ transaction, "HEAD",
+ u->flags | REF_LOG_ONLY | REF_NO_DEREF,
+ &u->new_oid, &u->old_oid, u->msg);
+ string_list_insert(&affected_refnames, new_update->refname);
+ }
+
+ ret = read_ref_without_reload(stack, rewritten_ref,
+ &current_oid, &referent, &u->type);
+ if (ret < 0)
+ goto done;
+ if (ret > 0 && (!(u->flags & REF_HAVE_OLD) || is_null_oid(&u->old_oid))) {
+ /*
+ * The reference does not exist, and we either have no
+ * old object ID or expect the reference to not exist.
+ * We can thus skip below safety checks as well as the
+ * symref splitting. But we do want to verify that
+ * there is no conflicting reference here so that we
+ * can output a proper error message instead of failing
+ * at a later point.
+ */
+ ret = refs_verify_refname_available(ref_store, u->refname,
+ &affected_refnames, NULL, err);
+ if (ret < 0)
+ goto done;
+
+ /*
+ * There is no need to write the reference deletion
+ * when the reference in question doesn't exist.
+ */
+ if (u->flags & REF_HAVE_NEW && !is_null_oid(&u->new_oid)) {
+ ret = queue_transaction_update(refs, tx_data, u,
+ &current_oid, err);
+ if (ret)
+ goto done;
+ }
+
+ continue;
+ }
+ if (ret > 0) {
+ /* The reference does not exist, but we expected it to. */
+ strbuf_addf(err, _("cannot lock ref '%s': "
+ "unable to resolve reference '%s'"),
+ original_update_refname(u), u->refname);
+ ret = -1;
+ goto done;
+ }
+
+ if (u->type & REF_ISSYMREF) {
+ /*
+ * The reftable stack is locked at this point already,
+ * so it is safe to call `refs_resolve_ref_unsafe()`
+ * here without causing races.
+ */
+ const char *resolved = refs_resolve_ref_unsafe(&refs->base, u->refname, 0,
+ &current_oid, NULL);
+
+ if (u->flags & REF_NO_DEREF) {
+ if (u->flags & REF_HAVE_OLD && !resolved) {
+ strbuf_addf(err, _("cannot lock ref '%s': "
+ "error reading reference"), u->refname);
+ ret = -1;
+ goto done;
+ }
+ } else {
+ struct ref_update *new_update;
+ int new_flags;
+
+ new_flags = u->flags;
+ if (!strcmp(rewritten_ref, "HEAD"))
+ new_flags |= REF_UPDATE_VIA_HEAD;
+
+ /*
+ * If we are updating a symref (eg. HEAD), we should also
+ * update the branch that the symref points to.
+ *
+ * This is generic functionality, and would be better
+ * done in refs.c, but the current implementation is
+ * intertwined with the locking in files-backend.c.
+ */
+ new_update = ref_transaction_add_update(
+ transaction, referent.buf, new_flags,
+ &u->new_oid, &u->old_oid, u->msg);
+ new_update->parent_update = u;
+
+ /*
+ * Change the symbolic ref update to log only. Also, it
+ * doesn't need to check its old OID value, as that will be
+ * done when new_update is processed.
+ */
+ u->flags |= REF_LOG_ONLY | REF_NO_DEREF;
+ u->flags &= ~REF_HAVE_OLD;
+
+ if (string_list_has_string(&affected_refnames, new_update->refname)) {
+ strbuf_addf(err,
+ _("multiple updates for '%s' (including one "
+ "via symref '%s') are not allowed"),
+ referent.buf, u->refname);
+ ret = TRANSACTION_NAME_CONFLICT;
+ goto done;
+ }
+ string_list_insert(&affected_refnames, new_update->refname);
+ }
+ }
+
+ /*
+ * Verify that the old object matches our expectations. Note
+ * that the error messages here do not make a lot of sense in
+ * the context of the reftable backend as we never lock
+ * individual refs. But the error messages match what the files
+ * backend returns, which keeps our tests happy.
+ */
+ if (u->flags & REF_HAVE_OLD && !oideq(&current_oid, &u->old_oid)) {
+ if (is_null_oid(&u->old_oid))
+ strbuf_addf(err, _("cannot lock ref '%s': "
+ "reference already exists"),
+ original_update_refname(u));
+ else if (is_null_oid(&current_oid))
+ strbuf_addf(err, _("cannot lock ref '%s': "
+ "reference is missing but expected %s"),
+ original_update_refname(u),
+ oid_to_hex(&u->old_oid));
+ else
+ strbuf_addf(err, _("cannot lock ref '%s': "
+ "is at %s but expected %s"),
+ original_update_refname(u),
+ oid_to_hex(&current_oid),
+ oid_to_hex(&u->old_oid));
+ ret = -1;
+ goto done;
+ }
+
+ /*
+ * If all of the following conditions are true:
+ *
+ * - We're not about to write a symref.
+ * - We're not about to write a log-only entry.
+ * - Old and new object ID are different.
+ *
+ * Then we're essentially doing a no-op update that can be
+ * skipped. This is not only for the sake of efficiency, but
+ * also skips writing unneeded reflog entries.
+ */
+ if ((u->type & REF_ISSYMREF) ||
+ (u->flags & REF_LOG_ONLY) ||
+ (u->flags & REF_HAVE_NEW && !oideq(&current_oid, &u->new_oid))) {
+ ret = queue_transaction_update(refs, tx_data, u,
+ &current_oid, err);
+ if (ret)
+ goto done;
+ }
+ }
+
+ transaction->backend_data = tx_data;
+ transaction->state = REF_TRANSACTION_PREPARED;
+
+done:
+ assert(ret != REFTABLE_API_ERROR);
+ if (ret < 0) {
+ free_transaction_data(tx_data);
+ transaction->state = REF_TRANSACTION_CLOSED;
+ if (!err->len)
+ strbuf_addf(err, _("reftable: transaction prepare: %s"),
+ reftable_error_str(ret));
+ }
+ string_list_clear(&affected_refnames, 0);
+ strbuf_release(&referent);
+ strbuf_release(&head_referent);
+
+ return ret;
+}
+
+static int reftable_be_transaction_abort(struct ref_store *ref_store,
+ struct ref_transaction *transaction,
+ struct strbuf *err)
+{
+ struct reftable_transaction_data *tx_data = transaction->backend_data;
+ free_transaction_data(tx_data);
+ transaction->state = REF_TRANSACTION_CLOSED;
+ return 0;
+}
+
+static int transaction_update_cmp(const void *a, const void *b)
+{
+ return strcmp(((struct reftable_transaction_update *)a)->update->refname,
+ ((struct reftable_transaction_update *)b)->update->refname);
+}
+
+static int write_transaction_table(struct reftable_writer *writer, void *cb_data)
+{
+ struct write_transaction_table_arg *arg = cb_data;
+ struct reftable_merged_table *mt =
+ reftable_stack_merged_table(arg->stack);
+ uint64_t ts = reftable_stack_next_update_index(arg->stack);
+ struct reftable_log_record *logs = NULL;
+ size_t logs_nr = 0, logs_alloc = 0, i;
+ int ret = 0;
+
+ QSORT(arg->updates, arg->updates_nr, transaction_update_cmp);
+
+ reftable_writer_set_limits(writer, ts, ts);
+
+ for (i = 0; i < arg->updates_nr; i++) {
+ struct reftable_transaction_update *tx_update = &arg->updates[i];
+ struct ref_update *u = tx_update->update;
+
+ /*
+ * Write a reflog entry when updating a ref to point to
+ * something new in either of the following cases:
+ *
+ * - The reference is about to be deleted. We always want to
+ * delete the reflog in that case.
+ * - REF_FORCE_CREATE_REFLOG is set, asking us to always create
+ * the reflog entry.
+ * - `core.logAllRefUpdates` tells us to create the reflog for
+ * the given ref.
+ */
+ if (u->flags & REF_HAVE_NEW && !(u->type & REF_ISSYMREF) && is_null_oid(&u->new_oid)) {
+ struct reftable_log_record log = {0};
+ struct reftable_iterator it = {0};
+
+ /*
+ * When deleting refs we also delete all reflog entries
+ * with them. While it is not strictly required to
+ * delete reflogs together with their refs, this
+ * matches the behaviour of the files backend.
+ *
+ * Unfortunately, we have no better way than to delete
+ * all reflog entries one by one.
+ */
+ ret = reftable_merged_table_seek_log(mt, &it, u->refname);
+ while (ret == 0) {
+ struct reftable_log_record *tombstone;
+
+ ret = reftable_iterator_next_log(&it, &log);
+ if (ret < 0)
+ break;
+ if (ret > 0 || strcmp(log.refname, u->refname)) {
+ ret = 0;
+ break;
+ }
+
+ ALLOC_GROW(logs, logs_nr + 1, logs_alloc);
+ tombstone = &logs[logs_nr++];
+ tombstone->refname = xstrdup(u->refname);
+ tombstone->value_type = REFTABLE_LOG_DELETION;
+ tombstone->update_index = log.update_index;
+ }
+
+ reftable_log_record_release(&log);
+ reftable_iterator_destroy(&it);
+
+ if (ret)
+ goto done;
+ } else if (u->flags & REF_HAVE_NEW &&
+ (u->flags & REF_FORCE_CREATE_REFLOG ||
+ should_write_log(&arg->refs->base, u->refname))) {
+ struct reftable_log_record *log;
+
+ ALLOC_GROW(logs, logs_nr + 1, logs_alloc);
+ log = &logs[logs_nr++];
+ memset(log, 0, sizeof(*log));
+
+ fill_reftable_log_record(log);
+ log->update_index = ts;
+ log->refname = xstrdup(u->refname);
+ memcpy(log->value.update.new_hash, u->new_oid.hash, GIT_MAX_RAWSZ);
+ memcpy(log->value.update.old_hash, tx_update->current_oid.hash, GIT_MAX_RAWSZ);
+ log->value.update.message =
+ xstrndup(u->msg, arg->refs->write_options.block_size / 2);
+ }
+
+ if (u->flags & REF_LOG_ONLY)
+ continue;
+
+ if (u->flags & REF_HAVE_NEW && is_null_oid(&u->new_oid)) {
+ struct reftable_ref_record ref = {
+ .refname = (char *)u->refname,
+ .update_index = ts,
+ .value_type = REFTABLE_REF_DELETION,
+ };
+
+ ret = reftable_writer_add_ref(writer, &ref);
+ if (ret < 0)
+ goto done;
+ } else if (u->flags & REF_HAVE_NEW) {
+ struct reftable_ref_record ref = {0};
+ struct object_id peeled;
+ int peel_error;
+
+ ref.refname = (char *)u->refname;
+ ref.update_index = ts;
+
+ peel_error = peel_object(&u->new_oid, &peeled);
+ if (!peel_error) {
+ ref.value_type = REFTABLE_REF_VAL2;
+ memcpy(ref.value.val2.target_value, peeled.hash, GIT_MAX_RAWSZ);
+ memcpy(ref.value.val2.value, u->new_oid.hash, GIT_MAX_RAWSZ);
+ } else if (!is_null_oid(&u->new_oid)) {
+ ref.value_type = REFTABLE_REF_VAL1;
+ memcpy(ref.value.val1, u->new_oid.hash, GIT_MAX_RAWSZ);
+ }
+
+ ret = reftable_writer_add_ref(writer, &ref);
+ if (ret < 0)
+ goto done;
+ }
+ }
+
+ /*
+ * Logs are written at the end so that we do not have intermixed ref
+ * and log blocks.
+ */
+ if (logs) {
+ ret = reftable_writer_add_logs(writer, logs, logs_nr);
+ if (ret < 0)
+ goto done;
+ }
+
+done:
+ assert(ret != REFTABLE_API_ERROR);
+ for (i = 0; i < logs_nr; i++)
+ reftable_log_record_release(&logs[i]);
+ free(logs);
+ return ret;
+}
+
+static int reftable_be_transaction_finish(struct ref_store *ref_store,
+ struct ref_transaction *transaction,
+ struct strbuf *err)
+{
+ struct reftable_transaction_data *tx_data = transaction->backend_data;
+ int ret = 0;
+
+ for (size_t i = 0; i < tx_data->args_nr; i++) {
+ ret = reftable_addition_add(tx_data->args[i].addition,
+ write_transaction_table, &tx_data->args[i]);
+ if (ret < 0)
+ goto done;
+
+ ret = reftable_addition_commit(tx_data->args[i].addition);
+ if (ret < 0)
+ goto done;
+ }
+
+done:
+ assert(ret != REFTABLE_API_ERROR);
+ free_transaction_data(tx_data);
+ transaction->state = REF_TRANSACTION_CLOSED;
+
+ if (ret) {
+ strbuf_addf(err, _("reftable: transaction failure: %s"),
+ reftable_error_str(ret));
+ return -1;
+ }
+ return ret;
+}
+
+static int reftable_be_initial_transaction_commit(struct ref_store *ref_store UNUSED,
+ struct ref_transaction *transaction,
+ struct strbuf *err)
+{
+ return ref_transaction_commit(transaction, err);
+}
+
+static int reftable_be_pack_refs(struct ref_store *ref_store,
+ struct pack_refs_opts *opts)
+{
+ struct reftable_ref_store *refs =
+ reftable_be_downcast(ref_store, REF_STORE_WRITE | REF_STORE_ODB, "pack_refs");
+ struct reftable_stack *stack;
+ int ret;
+
+ if (refs->err)
+ return refs->err;
+
+ stack = refs->worktree_stack;
+ if (!stack)
+ stack = refs->main_stack;
+
+ if (opts->flags & PACK_REFS_AUTO)
+ ret = reftable_stack_auto_compact(stack);
+ else
+ ret = reftable_stack_compact_all(stack, NULL);
+ if (ret < 0) {
+ ret = error(_("unable to compact stack: %s"),
+ reftable_error_str(ret));
+ goto out;
+ }
+
+ ret = reftable_stack_clean(stack);
+ if (ret)
+ goto out;
+
+out:
+ return ret;
+}
+
+struct write_create_symref_arg {
+ struct reftable_ref_store *refs;
+ struct reftable_stack *stack;
+ const char *refname;
+ const char *target;
+ const char *logmsg;
+};
+
+static int write_create_symref_table(struct reftable_writer *writer, void *cb_data)
+{
+ struct write_create_symref_arg *create = cb_data;
+ uint64_t ts = reftable_stack_next_update_index(create->stack);
+ struct reftable_ref_record ref = {
+ .refname = (char *)create->refname,
+ .value_type = REFTABLE_REF_SYMREF,
+ .value.symref = (char *)create->target,
+ .update_index = ts,
+ };
+ struct reftable_log_record log = {0};
+ struct object_id new_oid;
+ struct object_id old_oid;
+ int ret;
+
+ reftable_writer_set_limits(writer, ts, ts);
+
+ ret = reftable_writer_add_ref(writer, &ref);
+ if (ret)
+ return ret;
+
+ /*
+ * Note that it is important to try and resolve the reference before we
+ * write the log entry. This is because `should_write_log()` will munge
+ * `core.logAllRefUpdates`, which is undesirable when we create a new
+ * repository because it would be written into the config. As HEAD will
+ * not resolve for new repositories this ordering will ensure that this
+ * never happens.
+ */
+ if (!create->logmsg ||
+ !refs_resolve_ref_unsafe(&create->refs->base, create->target,
+ RESOLVE_REF_READING, &new_oid, NULL) ||
+ !should_write_log(&create->refs->base, create->refname))
+ return 0;
+
+ fill_reftable_log_record(&log);
+ log.refname = xstrdup(create->refname);
+ log.update_index = ts;
+ log.value.update.message = xstrndup(create->logmsg,
+ create->refs->write_options.block_size / 2);
+ memcpy(log.value.update.new_hash, new_oid.hash, GIT_MAX_RAWSZ);
+ if (refs_resolve_ref_unsafe(&create->refs->base, create->refname,
+ RESOLVE_REF_READING, &old_oid, NULL))
+ memcpy(log.value.update.old_hash, old_oid.hash, GIT_MAX_RAWSZ);
+
+ ret = reftable_writer_add_log(writer, &log);
+ reftable_log_record_release(&log);
+ return ret;
+}
+
+static int reftable_be_create_symref(struct ref_store *ref_store,
+ const char *refname,
+ const char *target,
+ const char *logmsg)
+{
+ struct reftable_ref_store *refs =
+ reftable_be_downcast(ref_store, REF_STORE_WRITE, "create_symref");
+ struct reftable_stack *stack = stack_for(refs, refname, &refname);
+ struct write_create_symref_arg arg = {
+ .refs = refs,
+ .stack = stack,
+ .refname = refname,
+ .target = target,
+ .logmsg = logmsg,
+ };
+ int ret;
+
+ ret = refs->err;
+ if (ret < 0)
+ goto done;
+
+ ret = reftable_stack_reload(stack);
+ if (ret)
+ goto done;
+
+ ret = reftable_stack_add(stack, &write_create_symref_table, &arg);
+
+done:
+ assert(ret != REFTABLE_API_ERROR);
+ if (ret)
+ error("unable to write symref for %s: %s", refname,
+ reftable_error_str(ret));
+ return ret;
+}
+
+struct write_copy_arg {
+ struct reftable_ref_store *refs;
+ struct reftable_stack *stack;
+ const char *oldname;
+ const char *newname;
+ const char *logmsg;
+ int delete_old;
+};
+
+static int write_copy_table(struct reftable_writer *writer, void *cb_data)
+{
+ struct write_copy_arg *arg = cb_data;
+ uint64_t deletion_ts, creation_ts;
+ struct reftable_merged_table *mt = reftable_stack_merged_table(arg->stack);
+ struct reftable_ref_record old_ref = {0}, refs[2] = {0};
+ struct reftable_log_record old_log = {0}, *logs = NULL;
+ struct reftable_iterator it = {0};
+ struct string_list skip = STRING_LIST_INIT_NODUP;
+ struct strbuf errbuf = STRBUF_INIT;
+ size_t logs_nr = 0, logs_alloc = 0, i;
+ int ret;
+
+ if (reftable_stack_read_ref(arg->stack, arg->oldname, &old_ref)) {
+ ret = error(_("refname %s not found"), arg->oldname);
+ goto done;
+ }
+ if (old_ref.value_type == REFTABLE_REF_SYMREF) {
+ ret = error(_("refname %s is a symbolic ref, copying it is not supported"),
+ arg->oldname);
+ goto done;
+ }
+
+ /*
+ * There's nothing to do in case the old and new name are the same, so
+ * we exit early in that case.
+ */
+ if (!strcmp(arg->oldname, arg->newname)) {
+ ret = 0;
+ goto done;
+ }
+
+ /*
+ * Verify that the new refname is available.
+ */
+ string_list_insert(&skip, arg->oldname);
+ ret = refs_verify_refname_available(&arg->refs->base, arg->newname,
+ NULL, &skip, &errbuf);
+ if (ret < 0) {
+ error("%s", errbuf.buf);
+ goto done;
+ }
+
+ /*
+ * When deleting the old reference we have to use two update indices:
+ * once to delete the old ref and its reflog, and once to create the
+ * new ref and its reflog. They need to be staged with two separate
+ * indices because the new reflog needs to encode both the deletion of
+ * the old branch and the creation of the new branch, and we cannot do
+ * two changes to a reflog in a single update.
+ */
+ deletion_ts = creation_ts = reftable_stack_next_update_index(arg->stack);
+ if (arg->delete_old)
+ creation_ts++;
+ reftable_writer_set_limits(writer, deletion_ts, creation_ts);
+
+ /*
+ * Add the new reference. If this is a rename then we also delete the
+ * old reference.
+ */
+ refs[0] = old_ref;
+ refs[0].refname = (char *)arg->newname;
+ refs[0].update_index = creation_ts;
+ if (arg->delete_old) {
+ refs[1].refname = (char *)arg->oldname;
+ refs[1].value_type = REFTABLE_REF_DELETION;
+ refs[1].update_index = deletion_ts;
+ }
+ ret = reftable_writer_add_refs(writer, refs, arg->delete_old ? 2 : 1);
+ if (ret < 0)
+ goto done;
+
+ /*
+ * When deleting the old branch we need to create a reflog entry on the
+ * new branch name that indicates that the old branch has been deleted
+ * and then recreated. This is a tad weird, but matches what the files
+ * backend does.
+ */
+ if (arg->delete_old) {
+ struct strbuf head_referent = STRBUF_INIT;
+ struct object_id head_oid;
+ int append_head_reflog;
+ unsigned head_type = 0;
+
+ ALLOC_GROW(logs, logs_nr + 1, logs_alloc);
+ memset(&logs[logs_nr], 0, sizeof(logs[logs_nr]));
+ fill_reftable_log_record(&logs[logs_nr]);
+ logs[logs_nr].refname = (char *)arg->newname;
+ logs[logs_nr].update_index = deletion_ts;
+ logs[logs_nr].value.update.message =
+ xstrndup(arg->logmsg, arg->refs->write_options.block_size / 2);
+ memcpy(logs[logs_nr].value.update.old_hash, old_ref.value.val1, GIT_MAX_RAWSZ);
+ logs_nr++;
+
+ ret = read_ref_without_reload(arg->stack, "HEAD", &head_oid, &head_referent, &head_type);
+ if (ret < 0)
+ goto done;
+ append_head_reflog = (head_type & REF_ISSYMREF) && !strcmp(head_referent.buf, arg->oldname);
+ strbuf_release(&head_referent);
+
+ /*
+ * The files backend uses `refs_delete_ref()` to delete the old
+ * branch name, which will append a reflog entry for HEAD in
+ * case it points to the old branch.
+ */
+ if (append_head_reflog) {
+ ALLOC_GROW(logs, logs_nr + 1, logs_alloc);
+ logs[logs_nr] = logs[logs_nr - 1];
+ logs[logs_nr].refname = "HEAD";
+ logs_nr++;
+ }
+ }
+
+ /*
+ * Create the reflog entry for the newly created branch.
+ */
+ ALLOC_GROW(logs, logs_nr + 1, logs_alloc);
+ memset(&logs[logs_nr], 0, sizeof(logs[logs_nr]));
+ fill_reftable_log_record(&logs[logs_nr]);
+ logs[logs_nr].refname = (char *)arg->newname;
+ logs[logs_nr].update_index = creation_ts;
+ logs[logs_nr].value.update.message =
+ xstrndup(arg->logmsg, arg->refs->write_options.block_size / 2);
+ memcpy(logs[logs_nr].value.update.new_hash, old_ref.value.val1, GIT_MAX_RAWSZ);
+ logs_nr++;
+
+ /*
+ * In addition to writing the reflog entry for the new branch, we also
+ * copy over all log entries from the old reflog. Last but not least,
+ * when renaming we also have to delete all the old reflog entries.
+ */
+ ret = reftable_merged_table_seek_log(mt, &it, arg->oldname);
+ if (ret < 0)
+ goto done;
+
+ while (1) {
+ ret = reftable_iterator_next_log(&it, &old_log);
+ if (ret < 0)
+ goto done;
+ if (ret > 0 || strcmp(old_log.refname, arg->oldname)) {
+ ret = 0;
+ break;
+ }
+
+ free(old_log.refname);
+
+ /*
+ * Copy over the old reflog entry with the new refname.
+ */
+ ALLOC_GROW(logs, logs_nr + 1, logs_alloc);
+ logs[logs_nr] = old_log;
+ logs[logs_nr].refname = (char *)arg->newname;
+ logs_nr++;
+
+ /*
+ * Delete the old reflog entry in case we are renaming.
+ */
+ if (arg->delete_old) {
+ ALLOC_GROW(logs, logs_nr + 1, logs_alloc);
+ memset(&logs[logs_nr], 0, sizeof(logs[logs_nr]));
+ logs[logs_nr].refname = (char *)arg->oldname;
+ logs[logs_nr].value_type = REFTABLE_LOG_DELETION;
+ logs[logs_nr].update_index = old_log.update_index;
+ logs_nr++;
+ }
+
+ /*
+ * Transfer ownership of the log record we're iterating over to
+ * the array of log records. Otherwise, the pointers would get
+ * free'd or reallocated by the iterator.
+ */
+ memset(&old_log, 0, sizeof(old_log));
+ }
+
+ ret = reftable_writer_add_logs(writer, logs, logs_nr);
+ if (ret < 0)
+ goto done;
+
+done:
+ assert(ret != REFTABLE_API_ERROR);
+ reftable_iterator_destroy(&it);
+ string_list_clear(&skip, 0);
+ strbuf_release(&errbuf);
+ for (i = 0; i < logs_nr; i++) {
+ if (!strcmp(logs[i].refname, "HEAD"))
+ continue;
+ logs[i].refname = NULL;
+ reftable_log_record_release(&logs[i]);
+ }
+ free(logs);
+ reftable_ref_record_release(&old_ref);
+ reftable_log_record_release(&old_log);
+ return ret;
+}
+
+static int reftable_be_rename_ref(struct ref_store *ref_store,
+ const char *oldrefname,
+ const char *newrefname,
+ const char *logmsg)
+{
+ struct reftable_ref_store *refs =
+ reftable_be_downcast(ref_store, REF_STORE_WRITE, "rename_ref");
+ struct reftable_stack *stack = stack_for(refs, newrefname, &newrefname);
+ struct write_copy_arg arg = {
+ .refs = refs,
+ .stack = stack,
+ .oldname = oldrefname,
+ .newname = newrefname,
+ .logmsg = logmsg,
+ .delete_old = 1,
+ };
+ int ret;
+
+ ret = refs->err;
+ if (ret < 0)
+ goto done;
+
+ ret = reftable_stack_reload(stack);
+ if (ret)
+ goto done;
+ ret = reftable_stack_add(stack, &write_copy_table, &arg);
+
+done:
+ assert(ret != REFTABLE_API_ERROR);
+ return ret;
+}
+
+static int reftable_be_copy_ref(struct ref_store *ref_store,
+ const char *oldrefname,
+ const char *newrefname,
+ const char *logmsg)
+{
+ struct reftable_ref_store *refs =
+ reftable_be_downcast(ref_store, REF_STORE_WRITE, "copy_ref");
+ struct reftable_stack *stack = stack_for(refs, newrefname, &newrefname);
+ struct write_copy_arg arg = {
+ .refs = refs,
+ .stack = stack,
+ .oldname = oldrefname,
+ .newname = newrefname,
+ .logmsg = logmsg,
+ };
+ int ret;
+
+ ret = refs->err;
+ if (ret < 0)
+ goto done;
+
+ ret = reftable_stack_reload(stack);
+ if (ret)
+ goto done;
+ ret = reftable_stack_add(stack, &write_copy_table, &arg);
+
+done:
+ assert(ret != REFTABLE_API_ERROR);
+ return ret;
+}
+
+struct reftable_reflog_iterator {
+ struct ref_iterator base;
+ struct reftable_ref_store *refs;
+ struct reftable_iterator iter;
+ struct reftable_log_record log;
+ struct strbuf last_name;
+ int err;
+};
+
+static int reftable_reflog_iterator_advance(struct ref_iterator *ref_iterator)
+{
+ struct reftable_reflog_iterator *iter =
+ (struct reftable_reflog_iterator *)ref_iterator;
+
+ while (!iter->err) {
+ iter->err = reftable_iterator_next_log(&iter->iter, &iter->log);
+ if (iter->err)
+ break;
+
+ /*
+ * We want the refnames that we have reflogs for, so we skip if
+ * we've already produced this name. This could be faster by
+ * seeking directly to reflog@update_index==0.
+ */
+ if (!strcmp(iter->log.refname, iter->last_name.buf))
+ continue;
+
+ if (check_refname_format(iter->log.refname,
+ REFNAME_ALLOW_ONELEVEL))
+ continue;
+
+ strbuf_reset(&iter->last_name);
+ strbuf_addstr(&iter->last_name, iter->log.refname);
+ iter->base.refname = iter->log.refname;
+
+ break;
+ }
+
+ if (iter->err > 0) {
+ if (ref_iterator_abort(ref_iterator) != ITER_DONE)
+ return ITER_ERROR;
+ return ITER_DONE;
+ }
+
+ if (iter->err < 0) {
+ ref_iterator_abort(ref_iterator);
+ return ITER_ERROR;
+ }
+
+ return ITER_OK;
+}
+
+static int reftable_reflog_iterator_peel(struct ref_iterator *ref_iterator,
+ struct object_id *peeled)
+{
+ BUG("reftable reflog iterator cannot be peeled");
+ return -1;
+}
+
+static int reftable_reflog_iterator_abort(struct ref_iterator *ref_iterator)
+{
+ struct reftable_reflog_iterator *iter =
+ (struct reftable_reflog_iterator *)ref_iterator;
+ reftable_log_record_release(&iter->log);
+ reftable_iterator_destroy(&iter->iter);
+ strbuf_release(&iter->last_name);
+ free(iter);
+ return ITER_DONE;
+}
+
+static struct ref_iterator_vtable reftable_reflog_iterator_vtable = {
+ .advance = reftable_reflog_iterator_advance,
+ .peel = reftable_reflog_iterator_peel,
+ .abort = reftable_reflog_iterator_abort
+};
+
+static struct reftable_reflog_iterator *reflog_iterator_for_stack(struct reftable_ref_store *refs,
+ struct reftable_stack *stack)
+{
+ struct reftable_merged_table *merged_table;
+ struct reftable_reflog_iterator *iter;
+ int ret;
+
+ iter = xcalloc(1, sizeof(*iter));
+ base_ref_iterator_init(&iter->base, &reftable_reflog_iterator_vtable);
+ strbuf_init(&iter->last_name, 0);
+ iter->refs = refs;
+
+ ret = refs->err;
+ if (ret)
+ goto done;
+
+ ret = reftable_stack_reload(stack);
+ if (ret < 0)
+ goto done;
+
+ merged_table = reftable_stack_merged_table(stack);
+
+ ret = reftable_merged_table_seek_log(merged_table, &iter->iter, "");
+ if (ret < 0)
+ goto done;
+
+done:
+ iter->err = ret;
+ return iter;
+}
+
+static struct ref_iterator *reftable_be_reflog_iterator_begin(struct ref_store *ref_store)
+{
+ struct reftable_ref_store *refs =
+ reftable_be_downcast(ref_store, REF_STORE_READ, "reflog_iterator_begin");
+ struct reftable_reflog_iterator *main_iter, *worktree_iter;
+
+ main_iter = reflog_iterator_for_stack(refs, refs->main_stack);
+ if (!refs->worktree_stack)
+ return &main_iter->base;
+
+ worktree_iter = reflog_iterator_for_stack(refs, refs->worktree_stack);
+
+ return merge_ref_iterator_begin(&worktree_iter->base, &main_iter->base,
+ ref_iterator_select, NULL);
+}
+
+static int yield_log_record(struct reftable_log_record *log,
+ each_reflog_ent_fn fn,
+ void *cb_data)
+{
+ struct object_id old_oid, new_oid;
+ const char *full_committer;
+
+ oidread(&old_oid, log->value.update.old_hash);
+ oidread(&new_oid, log->value.update.new_hash);
+
+ /*
+ * When both the old object ID and the new object ID are null
+ * then this is the reflog existence marker. The caller must
+ * not be aware of it.
+ */
+ if (is_null_oid(&old_oid) && is_null_oid(&new_oid))
+ return 0;
+
+ full_committer = fmt_ident(log->value.update.name, log->value.update.email,
+ WANT_COMMITTER_IDENT, NULL, IDENT_NO_DATE);
+ return fn(&old_oid, &new_oid, full_committer,
+ log->value.update.time, log->value.update.tz_offset,
+ log->value.update.message, cb_data);
+}
+
+static int reftable_be_for_each_reflog_ent_reverse(struct ref_store *ref_store,
+ const char *refname,
+ each_reflog_ent_fn fn,
+ void *cb_data)
+{
+ struct reftable_ref_store *refs =
+ reftable_be_downcast(ref_store, REF_STORE_READ, "for_each_reflog_ent_reverse");
+ struct reftable_stack *stack = stack_for(refs, refname, &refname);
+ struct reftable_merged_table *mt = NULL;
+ struct reftable_log_record log = {0};
+ struct reftable_iterator it = {0};
+ int ret;
+
+ if (refs->err < 0)
+ return refs->err;
+
+ mt = reftable_stack_merged_table(stack);
+ ret = reftable_merged_table_seek_log(mt, &it, refname);
+ while (!ret) {
+ ret = reftable_iterator_next_log(&it, &log);
+ if (ret < 0)
+ break;
+ if (ret > 0 || strcmp(log.refname, refname)) {
+ ret = 0;
+ break;
+ }
+
+ ret = yield_log_record(&log, fn, cb_data);
+ if (ret)
+ break;
+ }
+
+ reftable_log_record_release(&log);
+ reftable_iterator_destroy(&it);
+ return ret;
+}
+
+static int reftable_be_for_each_reflog_ent(struct ref_store *ref_store,
+ const char *refname,
+ each_reflog_ent_fn fn,
+ void *cb_data)
+{
+ struct reftable_ref_store *refs =
+ reftable_be_downcast(ref_store, REF_STORE_READ, "for_each_reflog_ent");
+ struct reftable_stack *stack = stack_for(refs, refname, &refname);
+ struct reftable_merged_table *mt = NULL;
+ struct reftable_log_record *logs = NULL;
+ struct reftable_iterator it = {0};
+ size_t logs_alloc = 0, logs_nr = 0, i;
+ int ret;
+
+ if (refs->err < 0)
+ return refs->err;
+
+ mt = reftable_stack_merged_table(stack);
+ ret = reftable_merged_table_seek_log(mt, &it, refname);
+ while (!ret) {
+ struct reftable_log_record log = {0};
+
+ ret = reftable_iterator_next_log(&it, &log);
+ if (ret < 0)
+ goto done;
+ if (ret > 0 || strcmp(log.refname, refname)) {
+ reftable_log_record_release(&log);
+ ret = 0;
+ break;
+ }
+
+ ALLOC_GROW(logs, logs_nr + 1, logs_alloc);
+ logs[logs_nr++] = log;
+ }
+
+ for (i = logs_nr; i--;) {
+ ret = yield_log_record(&logs[i], fn, cb_data);
+ if (ret)
+ goto done;
+ }
+
+done:
+ reftable_iterator_destroy(&it);
+ for (i = 0; i < logs_nr; i++)
+ reftable_log_record_release(&logs[i]);
+ free(logs);
+ return ret;
+}
+
+static int reftable_be_reflog_exists(struct ref_store *ref_store,
+ const char *refname)
+{
+ struct reftable_ref_store *refs =
+ reftable_be_downcast(ref_store, REF_STORE_READ, "reflog_exists");
+ struct reftable_stack *stack = stack_for(refs, refname, &refname);
+ struct reftable_merged_table *mt = reftable_stack_merged_table(stack);
+ struct reftable_log_record log = {0};
+ struct reftable_iterator it = {0};
+ int ret;
+
+ ret = refs->err;
+ if (ret < 0)
+ goto done;
+
+ ret = reftable_stack_reload(stack);
+ if (ret < 0)
+ goto done;
+
+ ret = reftable_merged_table_seek_log(mt, &it, refname);
+ if (ret < 0)
+ goto done;
+
+ /*
+ * Check whether we get at least one log record for the given ref name.
+ * If so, the reflog exists, otherwise it doesn't.
+ */
+ ret = reftable_iterator_next_log(&it, &log);
+ if (ret < 0)
+ goto done;
+ if (ret > 0) {
+ ret = 0;
+ goto done;
+ }
+
+ ret = strcmp(log.refname, refname) == 0;
+
+done:
+ reftable_iterator_destroy(&it);
+ reftable_log_record_release(&log);
+ if (ret < 0)
+ ret = 0;
+ return ret;
+}
+
+struct write_reflog_existence_arg {
+ struct reftable_ref_store *refs;
+ const char *refname;
+ struct reftable_stack *stack;
+};
+
+static int write_reflog_existence_table(struct reftable_writer *writer,
+ void *cb_data)
+{
+ struct write_reflog_existence_arg *arg = cb_data;
+ uint64_t ts = reftable_stack_next_update_index(arg->stack);
+ struct reftable_log_record log = {0};
+ int ret;
+
+ ret = reftable_stack_read_log(arg->stack, arg->refname, &log);
+ if (ret <= 0)
+ goto done;
+
+ reftable_writer_set_limits(writer, ts, ts);
+
+ /*
+ * The existence entry has both old and new object ID set to the the
+ * null object ID. Our iterators are aware of this and will not present
+ * them to their callers.
+ */
+ log.refname = xstrdup(arg->refname);
+ log.update_index = ts;
+ log.value_type = REFTABLE_LOG_UPDATE;
+ ret = reftable_writer_add_log(writer, &log);
+
+done:
+ assert(ret != REFTABLE_API_ERROR);
+ reftable_log_record_release(&log);
+ return ret;
+}
+
+static int reftable_be_create_reflog(struct ref_store *ref_store,
+ const char *refname,
+ struct strbuf *errmsg)
+{
+ struct reftable_ref_store *refs =
+ reftable_be_downcast(ref_store, REF_STORE_WRITE, "create_reflog");
+ struct reftable_stack *stack = stack_for(refs, refname, &refname);
+ struct write_reflog_existence_arg arg = {
+ .refs = refs,
+ .stack = stack,
+ .refname = refname,
+ };
+ int ret;
+
+ ret = refs->err;
+ if (ret < 0)
+ goto done;
+
+ ret = reftable_stack_reload(stack);
+ if (ret)
+ goto done;
+
+ ret = reftable_stack_add(stack, &write_reflog_existence_table, &arg);
+
+done:
+ return ret;
+}
+
+struct write_reflog_delete_arg {
+ struct reftable_stack *stack;
+ const char *refname;
+};
+
+static int write_reflog_delete_table(struct reftable_writer *writer, void *cb_data)
+{
+ struct write_reflog_delete_arg *arg = cb_data;
+ struct reftable_merged_table *mt =
+ reftable_stack_merged_table(arg->stack);
+ struct reftable_log_record log = {0}, tombstone = {0};
+ struct reftable_iterator it = {0};
+ uint64_t ts = reftable_stack_next_update_index(arg->stack);
+ int ret;
+
+ reftable_writer_set_limits(writer, ts, ts);
+
+ /*
+ * In order to delete a table we need to delete all reflog entries one
+ * by one. This is inefficient, but the reftable format does not have a
+ * better marker right now.
+ */
+ ret = reftable_merged_table_seek_log(mt, &it, arg->refname);
+ while (ret == 0) {
+ ret = reftable_iterator_next_log(&it, &log);
+ if (ret < 0)
+ break;
+ if (ret > 0 || strcmp(log.refname, arg->refname)) {
+ ret = 0;
+ break;
+ }
+
+ tombstone.refname = (char *)arg->refname;
+ tombstone.value_type = REFTABLE_LOG_DELETION;
+ tombstone.update_index = log.update_index;
+
+ ret = reftable_writer_add_log(writer, &tombstone);
+ }
+
+ reftable_log_record_release(&log);
+ reftable_iterator_destroy(&it);
+ return ret;
+}
+
+static int reftable_be_delete_reflog(struct ref_store *ref_store,
+ const char *refname)
+{
+ struct reftable_ref_store *refs =
+ reftable_be_downcast(ref_store, REF_STORE_WRITE, "delete_reflog");
+ struct reftable_stack *stack = stack_for(refs, refname, &refname);
+ struct write_reflog_delete_arg arg = {
+ .stack = stack,
+ .refname = refname,
+ };
+ int ret;
+
+ ret = reftable_stack_reload(stack);
+ if (ret)
+ return ret;
+ ret = reftable_stack_add(stack, &write_reflog_delete_table, &arg);
+
+ assert(ret != REFTABLE_API_ERROR);
+ return ret;
+}
+
+struct reflog_expiry_arg {
+ struct reftable_stack *stack;
+ struct reftable_log_record *records;
+ struct object_id update_oid;
+ const char *refname;
+ size_t len;
+};
+
+static int write_reflog_expiry_table(struct reftable_writer *writer, void *cb_data)
+{
+ struct reflog_expiry_arg *arg = cb_data;
+ uint64_t ts = reftable_stack_next_update_index(arg->stack);
+ uint64_t live_records = 0;
+ size_t i;
+ int ret;
+
+ for (i = 0; i < arg->len; i++)
+ if (arg->records[i].value_type == REFTABLE_LOG_UPDATE)
+ live_records++;
+
+ reftable_writer_set_limits(writer, ts, ts);
+
+ if (!is_null_oid(&arg->update_oid)) {
+ struct reftable_ref_record ref = {0};
+ struct object_id peeled;
+
+ ref.refname = (char *)arg->refname;
+ ref.update_index = ts;
+
+ if (!peel_object(&arg->update_oid, &peeled)) {
+ ref.value_type = REFTABLE_REF_VAL2;
+ memcpy(ref.value.val2.target_value, peeled.hash, GIT_MAX_RAWSZ);
+ memcpy(ref.value.val2.value, arg->update_oid.hash, GIT_MAX_RAWSZ);
+ } else {
+ ref.value_type = REFTABLE_REF_VAL1;
+ memcpy(ref.value.val1, arg->update_oid.hash, GIT_MAX_RAWSZ);
+ }
+
+ ret = reftable_writer_add_ref(writer, &ref);
+ if (ret < 0)
+ return ret;
+ }
+
+ /*
+ * When there are no more entries left in the reflog we empty it
+ * completely, but write a placeholder reflog entry that indicates that
+ * the reflog still exists.
+ */
+ if (!live_records) {
+ struct reftable_log_record log = {
+ .refname = (char *)arg->refname,
+ .value_type = REFTABLE_LOG_UPDATE,
+ .update_index = ts,
+ };
+
+ ret = reftable_writer_add_log(writer, &log);
+ if (ret)
+ return ret;
+ }
+
+ for (i = 0; i < arg->len; i++) {
+ ret = reftable_writer_add_log(writer, &arg->records[i]);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+
+static int reftable_be_reflog_expire(struct ref_store *ref_store,
+ const char *refname,
+ unsigned int flags,
+ reflog_expiry_prepare_fn prepare_fn,
+ reflog_expiry_should_prune_fn should_prune_fn,
+ reflog_expiry_cleanup_fn cleanup_fn,
+ void *policy_cb_data)
+{
+ /*
+ * For log expiry, we write tombstones for every single reflog entry
+ * that is to be expired. This means that the entries are still
+ * retrievable by delving into the stack, and expiring entries
+ * paradoxically takes extra memory. This memory is only reclaimed when
+ * compacting the reftable stack.
+ *
+ * It would be better if the refs backend supported an API that sets a
+ * criterion for all refs, passing the criterion to pack_refs().
+ *
+ * On the plus side, because we do the expiration per ref, we can easily
+ * insert the reflog existence dummies.
+ */
+ struct reftable_ref_store *refs =
+ reftable_be_downcast(ref_store, REF_STORE_WRITE, "reflog_expire");
+ struct reftable_stack *stack = stack_for(refs, refname, &refname);
+ struct reftable_merged_table *mt = reftable_stack_merged_table(stack);
+ struct reftable_log_record *logs = NULL;
+ struct reftable_log_record *rewritten = NULL;
+ struct reftable_ref_record ref_record = {0};
+ struct reftable_iterator it = {0};
+ struct reftable_addition *add = NULL;
+ struct reflog_expiry_arg arg = {0};
+ struct object_id oid = {0};
+ uint8_t *last_hash = NULL;
+ size_t logs_nr = 0, logs_alloc = 0, i;
+ int ret;
+
+ if (refs->err < 0)
+ return refs->err;
+
+ ret = reftable_stack_reload(stack);
+ if (ret < 0)
+ goto done;
+
+ ret = reftable_merged_table_seek_log(mt, &it, refname);
+ if (ret < 0)
+ goto done;
+
+ ret = reftable_stack_new_addition(&add, stack);
+ if (ret < 0)
+ goto done;
+
+ ret = reftable_stack_read_ref(stack, refname, &ref_record);
+ if (ret < 0)
+ goto done;
+ if (reftable_ref_record_val1(&ref_record))
+ oidread(&oid, reftable_ref_record_val1(&ref_record));
+ prepare_fn(refname, &oid, policy_cb_data);
+
+ while (1) {
+ struct reftable_log_record log = {0};
+ struct object_id old_oid, new_oid;
+
+ ret = reftable_iterator_next_log(&it, &log);
+ if (ret < 0)
+ goto done;
+ if (ret > 0 || strcmp(log.refname, refname)) {
+ reftable_log_record_release(&log);
+ break;
+ }
+
+ oidread(&old_oid, log.value.update.old_hash);
+ oidread(&new_oid, log.value.update.new_hash);
+
+ /*
+ * Skip over the reflog existence marker. We will add it back
+ * in when there are no live reflog records.
+ */
+ if (is_null_oid(&old_oid) && is_null_oid(&new_oid)) {
+ reftable_log_record_release(&log);
+ continue;
+ }
+
+ ALLOC_GROW(logs, logs_nr + 1, logs_alloc);
+ logs[logs_nr++] = log;
+ }
+
+ /*
+ * We need to rewrite all reflog entries according to the pruning
+ * callback function:
+ *
+ * - If a reflog entry shall be pruned we mark the record for
+ * deletion.
+ *
+ * - Otherwise we may have to rewrite the chain of reflog entries so
+ * that gaps created by just-deleted records get backfilled.
+ */
+ CALLOC_ARRAY(rewritten, logs_nr);
+ for (i = logs_nr; i--;) {
+ struct reftable_log_record *dest = &rewritten[i];
+ struct object_id old_oid, new_oid;
+
+ *dest = logs[i];
+ oidread(&old_oid, logs[i].value.update.old_hash);
+ oidread(&new_oid, logs[i].value.update.new_hash);
+
+ if (should_prune_fn(&old_oid, &new_oid, logs[i].value.update.email,
+ (timestamp_t)logs[i].value.update.time,
+ logs[i].value.update.tz_offset,
+ logs[i].value.update.message,
+ policy_cb_data)) {
+ dest->value_type = REFTABLE_LOG_DELETION;
+ } else {
+ if ((flags & EXPIRE_REFLOGS_REWRITE) && last_hash)
+ memcpy(dest->value.update.old_hash, last_hash, GIT_MAX_RAWSZ);
+ last_hash = logs[i].value.update.new_hash;
+ }
+ }
+
+ if (flags & EXPIRE_REFLOGS_UPDATE_REF && last_hash &&
+ reftable_ref_record_val1(&ref_record))
+ oidread(&arg.update_oid, last_hash);
+
+ arg.records = rewritten;
+ arg.len = logs_nr;
+ arg.stack = stack,
+ arg.refname = refname,
+
+ ret = reftable_addition_add(add, &write_reflog_expiry_table, &arg);
+ if (ret < 0)
+ goto done;
+
+ /*
+ * Future improvement: we could skip writing records that were
+ * not changed.
+ */
+ if (!(flags & EXPIRE_REFLOGS_DRY_RUN))
+ ret = reftable_addition_commit(add);
+
+done:
+ if (add)
+ cleanup_fn(policy_cb_data);
+ assert(ret != REFTABLE_API_ERROR);
+
+ reftable_ref_record_release(&ref_record);
+ reftable_iterator_destroy(&it);
+ reftable_addition_destroy(add);
+ for (i = 0; i < logs_nr; i++)
+ reftable_log_record_release(&logs[i]);
+ free(logs);
+ free(rewritten);
+ return ret;
+}
+
+struct ref_storage_be refs_be_reftable = {
+ .name = "reftable",
+ .init = reftable_be_init,
+ .init_db = reftable_be_init_db,
+ .transaction_prepare = reftable_be_transaction_prepare,
+ .transaction_finish = reftable_be_transaction_finish,
+ .transaction_abort = reftable_be_transaction_abort,
+ .initial_transaction_commit = reftable_be_initial_transaction_commit,
+
+ .pack_refs = reftable_be_pack_refs,
+ .create_symref = reftable_be_create_symref,
+ .rename_ref = reftable_be_rename_ref,
+ .copy_ref = reftable_be_copy_ref,
+
+ .iterator_begin = reftable_be_iterator_begin,
+ .read_raw_ref = reftable_be_read_raw_ref,
+ .read_symbolic_ref = reftable_be_read_symbolic_ref,
+
+ .reflog_iterator_begin = reftable_be_reflog_iterator_begin,
+ .for_each_reflog_ent = reftable_be_for_each_reflog_ent,
+ .for_each_reflog_ent_reverse = reftable_be_for_each_reflog_ent_reverse,
+ .reflog_exists = reftable_be_reflog_exists,
+ .create_reflog = reftable_be_create_reflog,
+ .delete_reflog = reftable_be_delete_reflog,
+ .reflog_expire = reftable_be_reflog_expire,
+};
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-26 09:10:24 +0000