Merge branch 'master' into ds/backfill

* master: (446 commits)
  The seventh batch
  The sixth batch
  The fifth batch
  The fourth batch
  refs/reftable: fix uninitialized memory access of `max_index`
  remote: announce removal of "branches/" and "remotes/"
  The third batch
  hash.h: drop unsafe_ function variants
  csum-file: introduce hashfile_checkpoint_init()
  t/helper/test-hash.c: use unsafe_hash_algo()
  csum-file.c: use unsafe_hash_algo()
  hash.h: introduce `unsafe_hash_algo()`
  csum-file.c: extract algop from hashfile_checksum_valid()
  csum-file: store the hash algorithm as a struct field
  t/helper/test-tool: implement sha1-unsafe helper
  trace2: prevent segfault on config collection with valueless true
  refs: fix creation of reflog entries for symrefs
  ci: wire up Visual Studio build with Meson
  ci: raise error when Meson generates warnings
  meson: fix compilation with Visual Studio
  ...

1 files changed, 227 insertions, 51 deletions

diff --git a/refs.c b/refs.c
index 762f3e324d..f4094a326a 100644
--- a/refs.c
+++ b/refs.c
@@ -3,6 +3,7 @@
  */
 
 #define USE_THE_REPOSITORY_VARIABLE
+#define DISABLE_SIGN_COMPARE_WARNINGS
 
 #include "git-compat-util.h"
 #include "advice.h"
@@ -30,6 +31,7 @@
 #include "date.h"
 #include "commit.h"
 #include "wildmatch.h"
+#include "ident.h"
 
 /*
  * List of all available backends
@@ -698,6 +700,53 @@ static char *substitute_branch_name(struct repository *r,
 	return NULL;
 }
 
+void copy_branchname(struct strbuf *sb, const char *name, unsigned allowed)
+{
+	int len = strlen(name);
+	struct interpret_branch_name_options options = {
+		.allowed = allowed
+	};
+	int used = repo_interpret_branch_name(the_repository, name, len, sb,
+					      &options);
+
+	if (used < 0)
+		used = 0;
+	strbuf_add(sb, name + used, len - used);
+}
+
+int check_branch_ref(struct strbuf *sb, const char *name)
+{
+	if (startup_info->have_repository)
+		copy_branchname(sb, name, INTERPRET_BRANCH_LOCAL);
+	else
+		strbuf_addstr(sb, name);
+
+	/*
+	 * This splice must be done even if we end up rejecting the
+	 * name; builtin/branch.c::copy_or_rename_branch() still wants
+	 * to see what the name expanded to so that "branch -m" can be
+	 * used as a tool to correct earlier mistakes.
+	 */
+	strbuf_splice(sb, 0, 0, "refs/heads/", 11);
+
+	if (*name == '-' ||
+	    !strcmp(sb->buf, "refs/heads/HEAD"))
+		return -1;
+
+	return check_refname_format(sb->buf, 0);
+}
+
+int check_tag_ref(struct strbuf *sb, const char *name)
+{
+	if (name[0] == '-' || !strcmp(name, "HEAD"))
+		return -1;
+
+	strbuf_reset(sb);
+	strbuf_addf(sb, "refs/tags/%s", name);
+
+	return check_refname_format(sb->buf, 0);
+}
+
 int repo_dwim_ref(struct repository *r, const char *str, int len,
 		  struct object_id *oid, char **ref, int nonfatal_dangling_mark)
 {
@@ -1151,6 +1200,7 @@ void ref_transaction_free(struct ref_transaction *transaction)
 
 	for (i = 0; i < transaction->nr; i++) {
 		free(transaction->updates[i]->msg);
+		free(transaction->updates[i]->committer_info);
 		free((char *)transaction->updates[i]->new_target);
 		free((char *)transaction->updates[i]->old_target);
 		free(transaction->updates[i]);
@@ -1165,6 +1215,7 @@ struct ref_update *ref_transaction_add_update(
 		const struct object_id *new_oid,
 		const struct object_id *old_oid,
 		const char *new_target, const char *old_target,
+		const char *committer_info,
 		const char *msg)
 {
 	struct ref_update *update;
@@ -1189,12 +1240,44 @@ struct ref_update *ref_transaction_add_update(
 		oidcpy(&update->new_oid, new_oid);
 	if ((flags & REF_HAVE_OLD) && old_oid)
 		oidcpy(&update->old_oid, old_oid);
-	if (!(flags & REF_SKIP_CREATE_REFLOG))
+	if (!(flags & REF_SKIP_CREATE_REFLOG)) {
+		update->committer_info = xstrdup_or_null(committer_info);
 		update->msg = normalize_reflog_message(msg);
+	}
 
 	return update;
 }
 
+static int transaction_refname_valid(const char *refname,
+				     const struct object_id *new_oid,
+				     unsigned int flags, struct strbuf *err)
+{
+	if (flags & REF_SKIP_REFNAME_VERIFICATION)
+		return 1;
+
+	if (is_pseudo_ref(refname)) {
+		const char *refusal_msg;
+		if (flags & REF_LOG_ONLY)
+			refusal_msg = _("refusing to update reflog for pseudoref '%s'");
+		else
+			refusal_msg = _("refusing to update pseudoref '%s'");
+		strbuf_addf(err, refusal_msg, refname);
+		return 0;
+	} else if ((new_oid && !is_null_oid(new_oid)) ?
+		 check_refname_format(refname, REFNAME_ALLOW_ONELEVEL) :
+		 !refname_is_safe(refname)) {
+		const char *refusal_msg;
+		if (flags & REF_LOG_ONLY)
+			refusal_msg = _("refusing to update reflog with bad name '%s'");
+		else
+			refusal_msg = _("refusing to update ref with bad name '%s'");
+		strbuf_addf(err, refusal_msg, refname);
+		return 0;
+	}
+
+	return 1;
+}
+
 int ref_transaction_update(struct ref_transaction *transaction,
 			   const char *refname,
 			   const struct object_id *new_oid,
@@ -1212,21 +1295,8 @@ int ref_transaction_update(struct ref_transaction *transaction,
 		return -1;
 	}
 
-	if (!(flags & REF_SKIP_REFNAME_VERIFICATION) &&
-	    ((new_oid && !is_null_oid(new_oid)) ?
-		     check_refname_format(refname, REFNAME_ALLOW_ONELEVEL) :
-			   !refname_is_safe(refname))) {
-		strbuf_addf(err, _("refusing to update ref with bad name '%s'"),
-			    refname);
+	if (!transaction_refname_valid(refname, new_oid, flags, err))
 		return -1;
-	}
-
-	if (!(flags & REF_SKIP_REFNAME_VERIFICATION) &&
-	    is_pseudo_ref(refname)) {
-		strbuf_addf(err, _("refusing to update pseudoref '%s'"),
-			    refname);
-		return -1;
-	}
 
 	if (flags & ~REF_TRANSACTION_UPDATE_ALLOWED_FLAGS)
 		BUG("illegal flags 0x%x passed to ref_transaction_update()", flags);
@@ -1243,7 +1313,45 @@ int ref_transaction_update(struct ref_transaction *transaction,
 
 	ref_transaction_add_update(transaction, refname, flags,
 				   new_oid, old_oid, new_target,
-				   old_target, msg);
+				   old_target, NULL, msg);
+
+	return 0;
+}
+
+int ref_transaction_update_reflog(struct ref_transaction *transaction,
+				  const char *refname,
+				  const struct object_id *new_oid,
+				  const struct object_id *old_oid,
+				  const char *committer_info, unsigned int flags,
+				  const char *msg, unsigned int index,
+				  struct strbuf *err)
+{
+	struct ref_update *update;
+
+	assert(err);
+
+	flags |= REF_LOG_ONLY | REF_FORCE_CREATE_REFLOG | REF_NO_DEREF;
+
+	if (!transaction_refname_valid(refname, new_oid, flags, err))
+		return -1;
+
+	update = ref_transaction_add_update(transaction, refname, flags,
+					    new_oid, old_oid, NULL, NULL,
+					    committer_info, msg);
+	/*
+	 * While we do set the old_oid value, we unset the flag to skip
+	 * old_oid verification which only makes sense for refs.
+	 */
+	update->flags &= ~REF_HAVE_OLD;
+	update->index = index;
+
+	/*
+	 * Reference backends may need to know the max index to optimize
+	 * their writes. So we store the max_index on the transaction level.
+	 */
+	if (index > transaction->max_index)
+		transaction->max_index = index;
+
 	return 0;
 }
 
@@ -2120,19 +2228,53 @@ int peel_iterated_oid(struct repository *r, const struct object_id *base, struct
 int refs_update_symref(struct ref_store *refs, const char *ref,
 		       const char *target, const char *logmsg)
 {
+	return refs_update_symref_extended(refs, ref, target, logmsg, NULL, 0);
+}
+
+int refs_update_symref_extended(struct ref_store *refs, const char *ref,
+		       const char *target, const char *logmsg,
+		       struct strbuf *referent, int create_only)
+{
 	struct ref_transaction *transaction;
 	struct strbuf err = STRBUF_INIT;
-	int ret = 0;
+	int ret = 0, prepret = 0;
 
 	transaction = ref_store_transaction_begin(refs, 0, &err);
-	if (!transaction ||
-	    ref_transaction_update(transaction, ref, NULL, NULL,
-				   target, NULL, REF_NO_DEREF,
-				   logmsg, &err) ||
-	    ref_transaction_commit(transaction, &err)) {
+	if (!transaction) {
+	error_return:
 		ret = error("%s", err.buf);
+		goto cleanup;
+	}
+	if (create_only) {
+		if (ref_transaction_create(transaction, ref, NULL, target,
+					   REF_NO_DEREF, logmsg, &err))
+			goto error_return;
+		prepret = ref_transaction_prepare(transaction, &err);
+		if (prepret && prepret != TRANSACTION_CREATE_EXISTS)
+			goto error_return;
+	} else {
+		if (ref_transaction_update(transaction, ref, NULL, NULL,
+					   target, NULL, REF_NO_DEREF,
+					   logmsg, &err) ||
+			ref_transaction_prepare(transaction, &err))
+			goto error_return;
+	}
+
+	if (referent && refs_read_symbolic_ref(refs, ref, referent) == NOT_A_SYMREF) {
+		struct object_id oid;
+		if (!refs_read_ref(refs, ref, &oid)) {
+			strbuf_addstr(referent, oid_to_hex(&oid));
+			ret = NOT_A_SYMREF;
+		}
 	}
 
+	if (prepret == TRANSACTION_CREATE_EXISTS)
+		goto cleanup;
+
+	if (ref_transaction_commit(transaction, &err))
+		goto error_return;
+
+cleanup:
 	strbuf_release(&err);
 	if (transaction)
 		ref_transaction_free(transaction);
@@ -2629,6 +2771,7 @@ struct migration_data {
 	struct ref_store *old_refs;
 	struct ref_transaction *transaction;
 	struct strbuf *errbuf;
+	struct strbuf sb;
 };
 
 static int migrate_one_ref(const char *refname, const char *referent UNUSED, const struct object_id *oid,
@@ -2661,6 +2804,52 @@ done:
 	return ret;
 }
 
+struct reflog_migration_data {
+	unsigned int index;
+	const char *refname;
+	struct ref_store *old_refs;
+	struct ref_transaction *transaction;
+	struct strbuf *errbuf;
+	struct strbuf *sb;
+};
+
+static int migrate_one_reflog_entry(struct object_id *old_oid,
+				    struct object_id *new_oid,
+				    const char *committer,
+				    timestamp_t timestamp, int tz,
+				    const char *msg, void *cb_data)
+{
+	struct reflog_migration_data *data = cb_data;
+	const char *date;
+	int ret;
+
+	date = show_date(timestamp, tz, DATE_MODE(NORMAL));
+	strbuf_reset(data->sb);
+	/* committer contains name and email */
+	strbuf_addstr(data->sb, fmt_ident("", committer, WANT_BLANK_IDENT, date, 0));
+
+	ret = ref_transaction_update_reflog(data->transaction, data->refname,
+					    new_oid, old_oid, data->sb->buf,
+					    REF_HAVE_NEW | REF_HAVE_OLD, msg,
+					    data->index++, data->errbuf);
+	return ret;
+}
+
+static int migrate_one_reflog(const char *refname, void *cb_data)
+{
+	struct migration_data *migration_data = cb_data;
+	struct reflog_migration_data data = {
+		.refname = refname,
+		.old_refs = migration_data->old_refs,
+		.transaction = migration_data->transaction,
+		.errbuf = migration_data->errbuf,
+		.sb = &migration_data->sb,
+	};
+
+	return refs_for_each_reflog_ent(migration_data->old_refs, refname,
+					migrate_one_reflog_entry, &data);
+}
+
 static int move_files(const char *from_path, const char *to_path, struct strbuf *errbuf)
 {
 	struct strbuf from_buf = STRBUF_INIT, to_buf = STRBUF_INIT;
@@ -2727,13 +2916,6 @@ done:
 	return ret;
 }
 
-static int count_reflogs(const char *reflog UNUSED, void *payload)
-{
-	size_t *reflog_count = payload;
-	(*reflog_count)++;
-	return 0;
-}
-
 static int has_worktrees(void)
 {
 	struct worktree **worktrees = get_worktrees();
@@ -2758,8 +2940,9 @@ int repo_migrate_ref_storage_format(struct repository *repo,
 	struct ref_store *old_refs = NULL, *new_refs = NULL;
 	struct ref_transaction *transaction = NULL;
 	struct strbuf new_gitdir = STRBUF_INIT;
-	struct migration_data data;
-	size_t reflog_count = 0;
+	struct migration_data data = {
+		.sb = STRBUF_INIT,
+	};
 	int did_migrate_refs = 0;
 	int ret;
 
@@ -2772,21 +2955,6 @@ int repo_migrate_ref_storage_format(struct repository *repo,
 	old_refs = get_main_ref_store(repo);
 
 	/*
-	 * We do not have any interfaces that would allow us to write many
-	 * reflog entries. Once we have them we can remove this restriction.
-	 */
-	if (refs_for_each_reflog(old_refs, count_reflogs, &reflog_count) < 0) {
-		strbuf_addstr(errbuf, "cannot count reflogs");
-		ret = -1;
-		goto done;
-	}
-	if (reflog_count) {
-		strbuf_addstr(errbuf, "migrating reflogs is not supported yet");
-		ret = -1;
-		goto done;
-	}
-
-	/*
 	 * Worktrees complicate the migration because every worktree has a
 	 * separate ref storage. While it should be feasible to implement, this
 	 * is pushed out to a future iteration.
@@ -2811,17 +2979,21 @@ int repo_migrate_ref_storage_format(struct repository *repo,
 	 *      This operation is safe as we do not yet modify the main
 	 *      repository.
 	 *
-	 *   3. If we're in dry-run mode then we are done and can hand over the
+	 *   3. Enumerate all reflogs and write them into the new ref storage.
+	 *      This operation is safe as we do not yet modify the main
+	 *      repository.
+	 *
+	 *   4. If we're in dry-run mode then we are done and can hand over the
 	 *      directory to the caller for inspection. If not, we now start
 	 *      with the destructive part.
 	 *
-	 *   4. Delete the old ref storage from disk. As we have a copy of refs
+	 *   5. Delete the old ref storage from disk. As we have a copy of refs
 	 *      in the new ref storage it's okay(ish) if we now get interrupted
 	 *      as there is an equivalent copy of all refs available.
 	 *
-	 *   5. Move the new ref storage files into place.
+	 *   6. Move the new ref storage files into place.
 	 *
-	 *   6. Change the repository format to the new ref format.
+	 *  7. Change the repository format to the new ref format.
 	 */
 	strbuf_addf(&new_gitdir, "%s/%s", old_refs->gitdir, "ref_migration.XXXXXX");
 	if (!mkdtemp(new_gitdir.buf)) {
@@ -2863,6 +3035,10 @@ int repo_migrate_ref_storage_format(struct repository *repo,
 	if (ret < 0)
 		goto done;
 
+	ret = refs_for_each_reflog(old_refs, migrate_one_reflog, &data);
+	if (ret < 0)
+		goto done;
+
 	ret = ref_transaction_commit(transaction, errbuf);
 	if (ret < 0)
 		goto done;
@@ -2938,6 +3114,7 @@ done:
 	}
 	ref_transaction_free(transaction);
 	strbuf_release(&new_gitdir);
+	strbuf_release(&data.sb);
 	return ret;
 }
 
@@ -2946,4 +3123,3 @@ int ref_update_expects_existing_old_ref(struct ref_update *update)
 	return (update->flags & REF_HAVE_OLD) &&
 		(!is_null_oid(&update->old_oid) || update->old_target);
 }
-