Re: [GSoC][PATCH v2 3/7] builtin/refs: add verify subcommand

> Introduce a new subcommand "verify" in git-refs(1) to allow the user to
> check the reference database consistency.
>
> Mentored-by: Patrick Steinhardt <ps@pks.im>
> Mentored-by: Karthik Nayak <karthik.188@gmail.com>
> Signed-off-by: shejialuo <shejialuo@gmail.com>
> ---
>  Documentation/git-refs.txt | 11 ++++++++++
>  builtin/refs.c             | 45 ++++++++++++++++++++++++++++++++++++++
>  2 files changed, 56 insertions(+)
>
> diff --git a/Documentation/git-refs.txt b/Documentation/git-refs.txt
> index 5b99e04385..f9d36ea19d 100644
> --- a/Documentation/git-refs.txt
> +++ b/Documentation/git-refs.txt
> @@ -10,6 +10,7 @@ SYNOPSIS
>  --------
>  [verse]
>  'git refs migrate' --ref-format=<format> [--dry-run]
> +'git refs verify' [--strict] [--verbose]
>
>  DESCRIPTION
>  -----------
> @@ -22,6 +23,9 @@ COMMANDS
>  migrate::
>  	Migrate ref store between different formats.
>
> +verify::
> +	Verify reference database consistency.
> +
>  OPTIONS
>  -------
>
> @@ -39,6 +43,13 @@ include::ref-storage-format.txt[]
>  	can be used to double check that the migration works as expected before
>  	performing the actual migration.
>

> +--strict::
> +	Enable more strict checking, every WARN severity for the `Fsck Messages`
> +	be seen as ERROR.
> +
> +--verbose::
> +	When verifying the reference database consistency, be chatty.
> +
>  KNOWN LIMITATIONS
>  -----------------
>
> diff --git a/builtin/refs.c b/builtin/refs.c
> index 46dcd150d4..82ed0d57c1 100644
> --- a/builtin/refs.c
> +++ b/builtin/refs.c
> @@ -1,4 +1,6 @@
>  #include "builtin.h"
> +#include "config.h"
> +#include "fsck.h"
>  #include "parse-options.h"
>  #include "refs.h"
>  #include "repository.h"
> @@ -7,6 +9,9 @@
>  #define REFS_MIGRATE_USAGE \
>  	N_("git refs migrate --ref-format=<format> [--dry-run]")
>
> +#define REFS_VERIFY_USAGE \
> +	N_("git refs verify [--strict] [--verbose]")
> +
>  static int cmd_refs_migrate(int argc, const char **argv, const char *prefix)
>  {
>  	const char * const migrate_usage[] = {
> @@ -58,15 +63,55 @@ static int cmd_refs_migrate(int argc, const char **argv, const char *prefix)
>  	return err;
>  }
>
> +static int cmd_refs_verify(int argc, const char **argv, const char *prefix)
> +{
> +	const char * const verify_usage[] = {
> +		REFS_VERIFY_USAGE,
> +		NULL,
> +	};
> +	int ret = 0;
> +	unsigned int verbose = 0, strict = 0;
> +	struct fsck_refs_options fsck_refs_options = FSCK_REFS_OPTIONS_DEFAULT;
> +	struct option options[] = {
> +		OPT__VERBOSE(&verbose, N_("be verbose")),
> +		OPT_BOOL(0, "strict", &strict, N_("enable strict checking")),
> +		OPT_END(),
> +	};
> +
> +	argc = parse_options(argc, argv, prefix, options, verify_usage, 0);
> +	if (argc)
> +		usage(_("too many arguments"));
> +
> +	if (verbose)
> +		fsck_refs_options.verbose = 1;
> +	if (strict)
> +		fsck_refs_options.strict = 1;
> +
> +	git_config(git_fsck_refs_config, &fsck_refs_options);
> +	prepare_repo_settings(the_repository);
> +
> +	ret = refs_fsck(get_main_ref_store(the_repository), &fsck_refs_options);
> +
> +	/*
> +	 * Explicitly free the allocated array. This is necessary because
> +	 * this program is executed as child process of git-fsck(1) and the
> +	 * allocated array may not freed when git-fsck(1) aborts somewhere.
> +	 */
> +	free(fsck_refs_options.msg_type);

> +	return ret;
> +}
> +
>  int cmd_refs(int argc, const char **argv, const char *prefix)
>  {
>  	const char * const refs_usage[] = {
>  		REFS_MIGRATE_USAGE,
> +		REFS_VERIFY_USAGE,
>  		NULL,
>  	};
>  	parse_opt_subcommand_fn *fn = NULL;
>  	struct option opts[] = {
>  		OPT_SUBCOMMAND("migrate", &fn, cmd_refs_migrate),
> +		OPT_SUBCOMMAND("verify", &fn, cmd_refs_verify),
>  		OPT_END(),
>  	};
>
> --
> 2.45.2