Merge branch 'ps/reflog-migrate-fixes' into ps/remote-rename-fix

* ps/reflog-migrate-fixes:
  refs: fix invalid old object IDs when migrating reflogs
  refs: stop unsetting REF_HAVE_OLD for log-only updates
  refs/files: detect race when generating reflog entry for HEAD
  refs: fix identity for migrated reflogs
  ident: fix type of string length parameter
  builtin/reflog: implement subcommand to write new entries
  refs: export `ref_transaction_update_reflog()`
  builtin/reflog: improve grouping of subcommands
  Documentation/git-reflog: convert to use synopsis type

Author: gitster

Documentation/git-reflog.adoc

@@ -8,16 +8,17 @@ git-reflog - Manage reflog information
 
 SYNOPSIS
 --------
-[verse]
-'git reflog' [show] [<log-options>] [<ref>]
-'git reflog list'
-'git reflog expire' [--expire=<time>] [--expire-unreachable=<time>]
+[synopsis]
+git reflog [show] [<log-options>] [<ref>]
+git reflog list
+git reflog exists <ref>
+git reflog write <ref> <old-oid> <new-oid> <message>
+git reflog delete [--rewrite] [--updateref]
+	[--dry-run | -n] [--verbose] <ref>@{<specifier>}...
+git reflog drop [--all [--single-worktree] | <refs>...]
+git reflog expire [--expire=<time>] [--expire-unreachable=<time>]
 	[--rewrite] [--updateref] [--stale-fix]
 	[--dry-run | -n] [--verbose] [--all [--single-worktree] | <refs>...]
-'git reflog delete' [--rewrite] [--updateref]
-	[--dry-run | -n] [--verbose] <ref>@{<specifier>}...
-'git reflog drop' [--all [--single-worktree] | <refs>...]
-'git reflog exists' <ref>
 
 DESCRIPTION
 -----------
@@ -43,11 +44,15 @@ actions, and in addition the `HEAD` reflog records branch switching.
 
 The "list" subcommand lists all refs which have a corresponding reflog.
 
-The "expire" subcommand prunes older reflog entries. Entries older
-than `expire` time, or entries older than `expire-unreachable` time
-and not reachable from the current tip, are removed from the reflog.
-This is typically not used directly by end users -- instead, see
-linkgit:git-gc[1].
+The "exists" subcommand checks whether a ref has a reflog.  It exits
+with zero status if the reflog exists, and non-zero status if it does
+not.
+
+The "write" subcommand writes a single entry to the reflog of a given
+reference. This new entry is appended to the reflog and will thus become
+the most recent entry. The reference name must be fully qualified. Both the old
+and new object IDs must not be abbreviated and must point to existing objects.
+The reflog message gets normalized.
 
 The "delete" subcommand deletes single entries from the reflog, but
 not the reflog itself. Its argument must be an _exact_ entry (e.g. "`git
@@ -58,9 +63,11 @@ The "drop" subcommand completely removes the reflog for the specified
 references. This is in contrast to "expire" and "delete", both of which
 can be used to delete reflog entries, but not the reflog itself.
 
-The "exists" subcommand checks whether a ref has a reflog.  It exits
-with zero status if the reflog exists, and non-zero status if it does
-not.
+The "expire" subcommand prunes older reflog entries. Entries older
+than `expire` time, or entries older than `expire-unreachable` time
+and not reachable from the current tip, are removed from the reflog.
+This is typically not used directly by end users -- instead, see
+linkgit:git-gc[1].
 
 OPTIONS
 -------
@@ -71,26 +78,45 @@ Options for `show`
 `git reflog show` accepts any of the options accepted by `git log`.
 
 
+Options for `delete`
+~~~~~~~~~~~~~~~~~~~~
+
+`git reflog delete` accepts options `--updateref`, `--rewrite`, `-n`,
+`--dry-run`, and `--verbose`, with the same meanings as when they are
+used with `expire`.
+
+Options for `drop`
+~~~~~~~~~~~~~~~~~~
+
+`--all`::
+	Drop the reflogs of all references from all worktrees.
+
+`--single-worktree`::
+	By default when `--all` is specified, reflogs from all working
+	trees are dropped. This option limits the processing to reflogs
+	from the current working tree only.
+
+
 Options for `expire`
 ~~~~~~~~~~~~~~~~~~~~
 
---all::
+`--all`::
 	Process the reflogs of all references.
 
---single-worktree::
+`--single-worktree`::
 	By default when `--all` is specified, reflogs from all working
 	trees are processed. This option limits the processing to reflogs
 	from the current working tree only.
 
---expire=<time>::
+`--expire=<time>`::
 	Prune entries older than the specified time. If this option is
 	not specified, the expiration time is taken from the
 	configuration setting `gc.reflogExpire`, which in turn
 	defaults to 90 days. `--expire=all` prunes entries regardless
 	of their age; `--expire=never` turns off pruning of reachable
 	entries (but see `--expire-unreachable`).
 
---expire-unreachable=<time>::
+`--expire-unreachable=<time>`::
 	Prune entries older than `<time>` that are not reachable from
 	the current tip of the branch. If this option is not
 	specified, the expiration time is taken from the configuration
@@ -100,17 +126,17 @@ Options for `expire`
 	turns off early pruning of unreachable entries (but see
 	`--expire`).
 
---updateref::
+`--updateref`::
 	Update the reference to the value of the top reflog entry (i.e.
 	<ref>@\{0\}) if the previous top entry was pruned.  (This
 	option is ignored for symbolic references.)
 
---rewrite::
+`--rewrite`::
 	If a reflog entry's predecessor is pruned, adjust its "old"
 	SHA-1 to be equal to the "new" SHA-1 field of the entry that
 	now precedes it.
 
---stale-fix::
+`--stale-fix`::
 	Prune any reflog entries that point to "broken commits". A
 	broken commit is a commit that is not reachable from any of
 	the reference tips and that refers, directly or indirectly, to
@@ -121,33 +147,15 @@ has the same cost as 'git prune'.  It is primarily intended to fix
 corruption caused by garbage collecting using older versions of Git,
 which didn't protect objects referred to by reflogs.
 
--n::
---dry-run::
+`-n`::
+`--dry-run`::
 	Do not actually prune any entries; just show what would have
 	been pruned.
 
---verbose::
+`--verbose`::
 	Print extra information on screen.
 
 
-Options for `delete`
-~~~~~~~~~~~~~~~~~~~~
-
-`git reflog delete` accepts options `--updateref`, `--rewrite`, `-n`,
-`--dry-run`, and `--verbose`, with the same meanings as when they are
-used with `expire`.
-
-Options for `drop`
-~~~~~~~~~~~~~~~~~~
-
---all::
-	Drop the reflogs of all references from all worktrees.
-
---single-worktree::
-	By default when `--all` is specified, reflogs from all working
-	trees are dropped. This option limits the processing to reflogs
-	from the current working tree only.
-
 GIT
 ---
 Part of the linkgit:git[1] suite

builtin/reflog.c

@@ -3,6 +3,8 @@
 #include "builtin.h"
 #include "config.h"
 #include "gettext.h"
+#include "hex.h"
+#include "odb.h"
 #include "revision.h"
 #include "reachable.h"
 #include "wildmatch.h"
@@ -17,21 +19,24 @@
 #define BUILTIN_REFLOG_LIST_USAGE \
 	N_("git reflog list")
 
-#define BUILTIN_REFLOG_EXPIRE_USAGE \
-	N_("git reflog expire [--expire=<time>] [--expire-unreachable=<time>]\n" \
-	   "                  [--rewrite] [--updateref] [--stale-fix]\n" \
-	   "                  [--dry-run | -n] [--verbose] [--all [--single-worktree] | <refs>...]")
+#define BUILTIN_REFLOG_EXISTS_USAGE \
+	N_("git reflog exists <ref>")
+
+#define BUILTIN_REFLOG_WRITE_USAGE \
+	N_("git reflog write <ref> <old-oid> <new-oid> <message>")
 
 #define BUILTIN_REFLOG_DELETE_USAGE \
 	N_("git reflog delete [--rewrite] [--updateref]\n" \
 	   "                  [--dry-run | -n] [--verbose] <ref>@{<specifier>}...")
 
-#define BUILTIN_REFLOG_EXISTS_USAGE \
-	N_("git reflog exists <ref>")
-
 #define BUILTIN_REFLOG_DROP_USAGE \
 	N_("git reflog drop [--all [--single-worktree] | <refs>...]")
 
+#define BUILTIN_REFLOG_EXPIRE_USAGE \
+	N_("git reflog expire [--expire=<time>] [--expire-unreachable=<time>]\n" \
+	   "                  [--rewrite] [--updateref] [--stale-fix]\n" \
+	   "                  [--dry-run | -n] [--verbose] [--all [--single-worktree] | <refs>...]")
+
 static const char *const reflog_show_usage[] = {
 	BUILTIN_REFLOG_SHOW_USAGE,
 	NULL,
@@ -42,33 +47,39 @@ static const char *const reflog_list_usage[] = {
 	NULL,
 };
 
-static const char *const reflog_expire_usage[] = {
-	BUILTIN_REFLOG_EXPIRE_USAGE,
-	NULL
+static const char *const reflog_exists_usage[] = {
+	BUILTIN_REFLOG_EXISTS_USAGE,
+	NULL,
+};
+
+static const char *const reflog_write_usage[] = {
+	BUILTIN_REFLOG_WRITE_USAGE,
+	NULL,
 };
 
 static const char *const reflog_delete_usage[] = {
 	BUILTIN_REFLOG_DELETE_USAGE,
 	NULL
 };
 
-static const char *const reflog_exists_usage[] = {
-	BUILTIN_REFLOG_EXISTS_USAGE,
-	NULL,
-};
-
 static const char *const reflog_drop_usage[] = {
 	BUILTIN_REFLOG_DROP_USAGE,
 	NULL,
 };
 
+static const char *const reflog_expire_usage[] = {
+	BUILTIN_REFLOG_EXPIRE_USAGE,
+	NULL
+};
+
 static const char *const reflog_usage[] = {
 	BUILTIN_REFLOG_SHOW_USAGE,
 	BUILTIN_REFLOG_LIST_USAGE,
-	BUILTIN_REFLOG_EXPIRE_USAGE,
+	BUILTIN_REFLOG_EXISTS_USAGE,
+	BUILTIN_REFLOG_WRITE_USAGE,
 	BUILTIN_REFLOG_DELETE_USAGE,
 	BUILTIN_REFLOG_DROP_USAGE,
-	BUILTIN_REFLOG_EXISTS_USAGE,
+	BUILTIN_REFLOG_EXPIRE_USAGE,
 	NULL
 };
 
@@ -392,6 +403,59 @@ static int cmd_reflog_drop(int argc, const char **argv, const char *prefix,
 	return ret;
 }
 
+static int cmd_reflog_write(int argc, const char **argv, const char *prefix,
+			    struct repository *repo)
+{
+	const struct option options[] = {
+		OPT_END()
+	};
+	struct object_id old_oid, new_oid;
+	struct strbuf err = STRBUF_INIT;
+	struct ref_transaction *tx;
+	const char *ref, *message;
+	int ret;
+
+	argc = parse_options(argc, argv, prefix, options, reflog_write_usage, 0);
+	if (argc != 4)
+		usage_with_options(reflog_write_usage, options);
+
+	ref = argv[0];
+	if (!is_root_ref(ref) && check_refname_format(ref, 0))
+		die(_("invalid reference name: %s"), ref);
+
+	ret = get_oid_hex_algop(argv[1], &old_oid, repo->hash_algo);
+	if (ret)
+		die(_("invalid old object ID: '%s'"), argv[1]);
+	if (!is_null_oid(&old_oid) && !has_object(the_repository, &old_oid, 0))
+		die(_("old object '%s' does not exist"), argv[1]);
+
+	ret = get_oid_hex_algop(argv[2], &new_oid, repo->hash_algo);
+	if (ret)
+		die(_("invalid new object ID: '%s'"), argv[2]);
+	if (!is_null_oid(&new_oid) && !has_object(the_repository, &new_oid, 0))
+		die(_("new object '%s' does not exist"), argv[2]);
+
+	message = argv[3];
+
+	tx = ref_store_transaction_begin(get_main_ref_store(repo), 0, &err);
+	if (!tx)
+		die(_("cannot start transaction: %s"), err.buf);
+
+	ret = ref_transaction_update_reflog(tx, ref, &new_oid, &old_oid,
+					    git_committer_info(0),
+					    message, 0, &err);
+	if (ret)
+		die(_("cannot queue reflog update: %s"), err.buf);
+
+	ret = ref_transaction_commit(tx, &err);
+	if (ret)
+		die(_("cannot commit reflog update: %s"), err.buf);
+
+	ref_transaction_free(tx);
+	strbuf_release(&err);
+	return 0;
+}
+
 /*
  * main "reflog"
  */
@@ -404,10 +468,11 @@ int cmd_reflog(int argc,
 	struct option options[] = {
 		OPT_SUBCOMMAND("show", &fn, cmd_reflog_show),
 		OPT_SUBCOMMAND("list", &fn, cmd_reflog_list),
-		OPT_SUBCOMMAND("expire", &fn, cmd_reflog_expire),
-		OPT_SUBCOMMAND("delete", &fn, cmd_reflog_delete),
 		OPT_SUBCOMMAND("exists", &fn, cmd_reflog_exists),
+		OPT_SUBCOMMAND("write", &fn, cmd_reflog_write),
+		OPT_SUBCOMMAND("delete", &fn, cmd_reflog_delete),
 		OPT_SUBCOMMAND("drop", &fn, cmd_reflog_drop),
+		OPT_SUBCOMMAND("expire", &fn, cmd_reflog_expire),
 		OPT_END()
 	};
 

ident.c

@@ -272,7 +272,7 @@ static void strbuf_addstr_without_crud(struct strbuf *sb, const char *src)
  * can still be NULL if the input line only has the name/email part
  * (e.g. reading from a reflog entry).
  */
-int split_ident_line(struct ident_split *split, const char *line, int len)
+int split_ident_line(struct ident_split *split, const char *line, size_t len)
 {
 	const char *cp;
 	size_t span;

ident.h

@@ -35,7 +35,7 @@ void reset_ident_date(void);
  * Signals an success with 0, but time part of the result may be NULL
  * if the input lacks timestamp and zone
  */
-int split_ident_line(struct ident_split *, const char *, int);
+int split_ident_line(struct ident_split *, const char *, size_t);
 
 /*
  * Given a commit or tag object buffer and the commit or tag headers, replaces