diff mbox series

[v2,3/4] bisect--helper: reimplement `bisect_run` shell function in C

Message ID 20210407173334.68222-4-mirucam@gmail.com (mailing list archive)
State Superseded
Headers show
Series Finish converting git bisect to C part 4 | expand

Commit Message

Miriam R. April 7, 2021, 5:33 p.m. UTC
From: Tanushree Tumane <tanushreetumane@gmail.com>

Reimplement the `bisect_run()` shell function
in C and also add `--bisect-run` subcommand to
`git bisect--helper` to call it from git-bisect.sh.

Mentored-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Tanushree Tumane <tanushreetumane@gmail.com>
Signed-off-by: Miriam Rubio <mirucam@gmail.com>
---
 builtin/bisect--helper.c | 71 +++++++++++++++++++++++++++++++++++++++-
 git-bisect.sh            | 62 +----------------------------------
 2 files changed, 71 insertions(+), 62 deletions(-)

Comments

Junio C Hamano April 7, 2021, 10:09 p.m. UTC | #1
Miriam Rubio <mirucam@gmail.com> writes:

> From: Tanushree Tumane <tanushreetumane@gmail.com>
>
> Reimplement the `bisect_run()` shell function
> in C and also add `--bisect-run` subcommand to
> `git bisect--helper` to call it from git-bisect.sh.
>
> Mentored-by: Christian Couder <chriscool@tuxfamily.org>
> Signed-off-by: Tanushree Tumane <tanushreetumane@gmail.com>
> Signed-off-by: Miriam Rubio <mirucam@gmail.com>

If I am reading the patch correctly, this removes the need for the
$GIT_DIR/BISECT_RUN file that used to be used to keep track of the
state?  If that is true, it is worth noting in the proposed log
message.

As far as I can see, nobody creates $GIT_DIR/BISECT_RUN anymore.

    $ git grep -e path_bisect_run -e BISECT_RUN
    bisect.c:static GIT_PATH_FUNC(git_path_bisect_run, "BISECT_RUN")
    bisect.c:	unlink_or_warn(git_path_bisect_run());
    builtin/bisect--helper.c:		BISECT_RUN,
    builtin/bisect--helper.c:			 N_("use <cmd>... to automatical...
    builtin/bisect--helper.c:	case BISECT_RUN:
    t/t6030-bisect-porcelain.sh:	test_path_is_missing ".git/BISECT_RUN" &&

What if a run script tried to read from (or checked the presence of)
the file for its correct operation (e.g. I would imagine that "do
this operation when run interactively, but do the same operation
silently when run from the git-bisect machinery" may be a reasonable
thing to do)?

This change just unintendedly broke such a script, didn't it?  The
change makes me a bit worried.

> +	if (bisect_next_check(terms, NULL))
> +		return BISECT_FAILED;
> +
> +	if (argc)
> +		sq_quote_argv(&command, argv);
> +	else
> +		return BISECT_FAILED;
> +
> +	run_args.v[0] = xstrdup(command.buf);
> +	run_args.nr = 1;
> +
> +	while (1) {
> +		strvec_clear(&args);
> +
> +		printf(_("running %s"), command.buf);
> +		res = run_command_v_opt(run_args.v, RUN_USING_SHELL);

Nicely used sq_quote_argv() with RUN_USING_SHELL here.  Goodl.

> +		if (res < 0 && res >= 128) {
> +			error(_("bisect run failed: exit code %d from"
> +				" '%s' is < 0 or >= 128"), res, command.buf);
> +			strbuf_release(&command);
> +			return res;
> +		}
> +
> +		if (res == 125)
> +			strvec_push(&args, "skip");
> +		else if (res > 0)
> +			strvec_push(&args, terms->term_bad);
> +		else
> +			strvec_push(&args, terms->term_good);
> +

bisect_state() does so much that it was a bit hard to follow for me
(who hasn't been following the bisect-in-C topic very closely), but
the code around here roughly corresponds to the following snippet in
the original scripted version.

> -		git bisect--helper --bisect-state $state >"$GIT_DIR/BISECT_RUN"
> -		res=$?
> -
> -		cat "$GIT_DIR/BISECT_RUN"
> -
> -		if sane_grep "first $TERM_BAD commit could be any of" "$GIT_DIR/BISECT_RUN" \
> -			>/dev/null
> -		then
> -			gettextln "bisect run cannot continue any more" >&2
> -			exit $res
> -		fi

I see that the contents of the file BISECT_RUN is shown to the user
in the original but is that part of what bisect_state() does, or did
we lose it during this round of conversion?

> +		res = bisect_state(terms, args.v, args.nr);
> +		if (res == BISECT_INTERNAL_SUCCESS_MERGE_BASE) {
> +			printf(_("bisect run success"));
> +			res = BISECT_OK;
> +		} else if (res == BISECT_ONLY_SKIPPED_LEFT)
> +			error(_("bisect run cannot continue any more"));
> +		else if (res)
> +			error(_("bisect run failed:'git bisect--helper --bisect-state"
> +				" %s' exited with error code %d"), args.v[0], res);
> +		else
> +			continue;

In any case, being able to check the return value from bisect_state()
and switch is so much nicer than having to sane_grep in BISECT_RUN.

> +		strbuf_release(&command);
> +		strvec_clear(&args);
> +		strvec_clear(&run_args);
> +
> +		return res;
> +	}
> +}
> +
>  int cmd_bisect__helper(int argc, const char **argv, const char *prefix)
>  {
>  	enum {
> @@ -1086,7 +1146,8 @@ int cmd_bisect__helper(int argc, const char **argv, const char *prefix)
>  		BISECT_LOG,
>  		BISECT_REPLAY,
>  		BISECT_SKIP,
> -		BISECT_VISUALIZE
> +		BISECT_VISUALIZE,
> +		BISECT_RUN,

Now this new one has the trailing comma.  I'd suggest doing so in
the previous step.

Thanks.
Junio C Hamano April 9, 2021, 6:15 a.m. UTC | #2
Miriam Rubio <mirucam@gmail.com> writes:

> +static int bisect_run(struct bisect_terms *terms, const char **argv, int argc)
> +{
> ...
> +	while (1) {
> +		strvec_clear(&args);
> +
> +		printf(_("running %s"), command.buf);
> +		res = run_command_v_opt(run_args.v, RUN_USING_SHELL);
> +
> +		if (res < 0 && res >= 128) {

Sorry for not noticing this total nonsense during my earlier review,
but this condition will never trigger.

I would have noticed it if the style consistently used "order
quantities from left to right, as if on a number line" convention,
i.e.

		if (res < 0 && 128 <= res) {

Because there are only two valid range notation around a single
variable, which are:

    (res < 0 || 128 <= res) - meaning 'res' is outside a span, or
    (0 <= res && res < 128) - meaning 'res' is inside a span.

and the above rewriten form is neither, it would have stood out
as an error immediately.
Miriam R. April 11, 2021, 10:04 a.m. UTC | #3
El jue, 8 abr 2021 a las 0:09, Junio C Hamano (<gitster@pobox.com>) escribió:
>
> Miriam Rubio <mirucam@gmail.com> writes:
>
> > From: Tanushree Tumane <tanushreetumane@gmail.com>
> >
> > Reimplement the `bisect_run()` shell function
> > in C and also add `--bisect-run` subcommand to
> > `git bisect--helper` to call it from git-bisect.sh.
> >
> > Mentored-by: Christian Couder <chriscool@tuxfamily.org>
> > Signed-off-by: Tanushree Tumane <tanushreetumane@gmail.com>
> > Signed-off-by: Miriam Rubio <mirucam@gmail.com>
>
> If I am reading the patch correctly, this removes the need for the
> $GIT_DIR/BISECT_RUN file that used to be used to keep track of the
> state?  If that is true, it is worth noting in the proposed log
> message.
>
> As far as I can see, nobody creates $GIT_DIR/BISECT_RUN anymore.
>
>     $ git grep -e path_bisect_run -e BISECT_RUN
>     bisect.c:static GIT_PATH_FUNC(git_path_bisect_run, "BISECT_RUN")
>     bisect.c:   unlink_or_warn(git_path_bisect_run());
>     builtin/bisect--helper.c:           BISECT_RUN,
>     builtin/bisect--helper.c:                    N_("use <cmd>... to automatical...
>     builtin/bisect--helper.c:   case BISECT_RUN:
>     t/t6030-bisect-porcelain.sh:        test_path_is_missing ".git/BISECT_RUN" &&
>
> What if a run script tried to read from (or checked the presence of)
> the file for its correct operation (e.g. I would imagine that "do
> this operation when run interactively, but do the same operation
> silently when run from the git-bisect machinery" may be a reasonable
> thing to do)?
>
> This change just unintendedly broke such a script, didn't it?  The
> change makes me a bit worried.
Hi,
thank you for reviewing!.
I don't know why the need for the $GIT_DIR/BISECT_RUN file was
removed, so in the last patch series version I have just sent,
I have added the creation of the file and it contains bisect_state()
output as in original shell script version.
Regards,
Miriam
>
> > +     if (bisect_next_check(terms, NULL))
> > +             return BISECT_FAILED;
> > +
> > +     if (argc)
> > +             sq_quote_argv(&command, argv);
> > +     else
> > +             return BISECT_FAILED;
> > +
> > +     run_args.v[0] = xstrdup(command.buf);
> > +     run_args.nr = 1;
> > +
> > +     while (1) {
> > +             strvec_clear(&args);
> > +
> > +             printf(_("running %s"), command.buf);
> > +             res = run_command_v_opt(run_args.v, RUN_USING_SHELL);
>
> Nicely used sq_quote_argv() with RUN_USING_SHELL here.  Goodl.
>
> > +             if (res < 0 && res >= 128) {
> > +                     error(_("bisect run failed: exit code %d from"
> > +                             " '%s' is < 0 or >= 128"), res, command.buf);
> > +                     strbuf_release(&command);
> > +                     return res;
> > +             }
> > +
> > +             if (res == 125)
> > +                     strvec_push(&args, "skip");
> > +             else if (res > 0)
> > +                     strvec_push(&args, terms->term_bad);
> > +             else
> > +                     strvec_push(&args, terms->term_good);
> > +
>
> bisect_state() does so much that it was a bit hard to follow for me
> (who hasn't been following the bisect-in-C topic very closely), but
> the code around here roughly corresponds to the following snippet in
> the original scripted version.
>
> > -             git bisect--helper --bisect-state $state >"$GIT_DIR/BISECT_RUN"
> > -             res=$?
> > -
> > -             cat "$GIT_DIR/BISECT_RUN"
> > -
> > -             if sane_grep "first $TERM_BAD commit could be any of" "$GIT_DIR/BISECT_RUN" \
> > -                     >/dev/null
> > -             then
> > -                     gettextln "bisect run cannot continue any more" >&2
> > -                     exit $res
> > -             fi
>
> I see that the contents of the file BISECT_RUN is shown to the user
> in the original but is that part of what bisect_state() does, or did
> we lose it during this round of conversion?
>
> > +             res = bisect_state(terms, args.v, args.nr);
> > +             if (res == BISECT_INTERNAL_SUCCESS_MERGE_BASE) {
> > +                     printf(_("bisect run success"));
> > +                     res = BISECT_OK;
> > +             } else if (res == BISECT_ONLY_SKIPPED_LEFT)
> > +                     error(_("bisect run cannot continue any more"));
> > +             else if (res)
> > +                     error(_("bisect run failed:'git bisect--helper --bisect-state"
> > +                             " %s' exited with error code %d"), args.v[0], res);
> > +             else
> > +                     continue;
>
> In any case, being able to check the return value from bisect_state()
> and switch is so much nicer than having to sane_grep in BISECT_RUN.
>
> > +             strbuf_release(&command);
> > +             strvec_clear(&args);
> > +             strvec_clear(&run_args);
> > +
> > +             return res;
> > +     }
> > +}
> > +
> >  int cmd_bisect__helper(int argc, const char **argv, const char *prefix)
> >  {
> >       enum {
> > @@ -1086,7 +1146,8 @@ int cmd_bisect__helper(int argc, const char **argv, const char *prefix)
> >               BISECT_LOG,
> >               BISECT_REPLAY,
> >               BISECT_SKIP,
> > -             BISECT_VISUALIZE
> > +             BISECT_VISUALIZE,
> > +             BISECT_RUN,
>
> Now this new one has the trailing comma.  I'd suggest doing so in
> the previous step.
>
> Thanks.
diff mbox series

Patch

diff --git a/builtin/bisect--helper.c b/builtin/bisect--helper.c
index b77c4f6b29..31c5f99660 100644
--- a/builtin/bisect--helper.c
+++ b/builtin/bisect--helper.c
@@ -31,6 +31,7 @@  static const char * const git_bisect_helper_usage[] = {
 	N_("git bisect--helper --bisect-replay <filename>"),
 	N_("git bisect--helper --bisect-skip [(<rev>|<range>)...]"),
 	N_("git bisect--helper --bisect-visualize"),
+	N_("git bisect--helper --bisect-run <cmd>..."),
 	NULL
 };
 
@@ -1073,6 +1074,65 @@  static int bisect_visualize(struct bisect_terms *terms, const char **argv, int a
 	return res;
 }
 
+static int bisect_run(struct bisect_terms *terms, const char **argv, int argc)
+{
+	int res = BISECT_OK;
+	struct strbuf command = STRBUF_INIT;
+	struct strvec args = STRVEC_INIT;
+	struct strvec run_args = STRVEC_INIT;
+
+	if (bisect_next_check(terms, NULL))
+		return BISECT_FAILED;
+
+	if (argc)
+		sq_quote_argv(&command, argv);
+	else
+		return BISECT_FAILED;
+
+	run_args.v[0] = xstrdup(command.buf);
+	run_args.nr = 1;
+
+	while (1) {
+		strvec_clear(&args);
+
+		printf(_("running %s"), command.buf);
+		res = run_command_v_opt(run_args.v, RUN_USING_SHELL);
+
+		if (res < 0 && res >= 128) {
+			error(_("bisect run failed: exit code %d from"
+				" '%s' is < 0 or >= 128"), res, command.buf);
+			strbuf_release(&command);
+			return res;
+		}
+
+		if (res == 125)
+			strvec_push(&args, "skip");
+		else if (res > 0)
+			strvec_push(&args, terms->term_bad);
+		else
+			strvec_push(&args, terms->term_good);
+
+		res = bisect_state(terms, args.v, args.nr);
+
+		if (res == BISECT_INTERNAL_SUCCESS_MERGE_BASE) {
+			printf(_("bisect run success"));
+			res = BISECT_OK;
+		} else if (res == BISECT_ONLY_SKIPPED_LEFT)
+			error(_("bisect run cannot continue any more"));
+		else if (res)
+			error(_("bisect run failed:'git bisect--helper --bisect-state"
+				" %s' exited with error code %d"), args.v[0], res);
+		else
+			continue;
+
+		strbuf_release(&command);
+		strvec_clear(&args);
+		strvec_clear(&run_args);
+
+		return res;
+	}
+}
+
 int cmd_bisect__helper(int argc, const char **argv, const char *prefix)
 {
 	enum {
@@ -1086,7 +1146,8 @@  int cmd_bisect__helper(int argc, const char **argv, const char *prefix)
 		BISECT_LOG,
 		BISECT_REPLAY,
 		BISECT_SKIP,
-		BISECT_VISUALIZE
+		BISECT_VISUALIZE,
+		BISECT_RUN,
 	} cmdmode = 0;
 	int res = 0, nolog = 0;
 	struct option options[] = {
@@ -1110,6 +1171,8 @@  int cmd_bisect__helper(int argc, const char **argv, const char *prefix)
 			 N_("skip some commits for checkout"), BISECT_SKIP),
 		OPT_CMDMODE(0, "bisect-visualize", &cmdmode,
 			 N_("visualize the bisection"), BISECT_VISUALIZE),
+		OPT_CMDMODE(0, "bisect-run", &cmdmode,
+			 N_("use <cmd>... to automatically bisect."), BISECT_RUN),
 		OPT_BOOL(0, "no-log", &nolog,
 			 N_("no log for BISECT_WRITE")),
 		OPT_END()
@@ -1174,6 +1237,12 @@  int cmd_bisect__helper(int argc, const char **argv, const char *prefix)
 		get_terms(&terms);
 		res = bisect_visualize(&terms, argv, argc);
 		break;
+	case BISECT_RUN:
+		if (!argc)
+			return error(_("bisect run failed: no command provided."));
+		get_terms(&terms);
+		res = bisect_run(&terms, argv, argc);
+		break;
 	default:
 		BUG("unknown subcommand %d", cmdmode);
 	}
diff --git a/git-bisect.sh b/git-bisect.sh
index 95f7f3fb8c..e83d011e17 100755
--- a/git-bisect.sh
+++ b/git-bisect.sh
@@ -39,66 +39,6 @@  _x40="$_x40$_x40$_x40$_x40$_x40$_x40$_x40$_x40"
 TERM_BAD=bad
 TERM_GOOD=good
 
-bisect_run () {
-	git bisect--helper --bisect-next-check $TERM_GOOD $TERM_BAD fail || exit
-
-	test -n "$*" || die "$(gettext "bisect run failed: no command provided.")"
-
-	while true
-	do
-		command="$@"
-		eval_gettextln "running \$command"
-		"$@"
-		res=$?
-
-		# Check for really bad run error.
-		if [ $res -lt 0 -o $res -ge 128 ]
-		then
-			eval_gettextln "bisect run failed:
-exit code \$res from '\$command' is < 0 or >= 128" >&2
-			exit $res
-		fi
-
-		# Find current state depending on run success or failure.
-		# A special exit code of 125 means cannot test.
-		if [ $res -eq 125 ]
-		then
-			state='skip'
-		elif [ $res -gt 0 ]
-		then
-			state="$TERM_BAD"
-		else
-			state="$TERM_GOOD"
-		fi
-
-		git bisect--helper --bisect-state $state >"$GIT_DIR/BISECT_RUN"
-		res=$?
-
-		cat "$GIT_DIR/BISECT_RUN"
-
-		if sane_grep "first $TERM_BAD commit could be any of" "$GIT_DIR/BISECT_RUN" \
-			>/dev/null
-		then
-			gettextln "bisect run cannot continue any more" >&2
-			exit $res
-		fi
-
-		if [ $res -ne 0 ]
-		then
-			eval_gettextln "bisect run failed:
-'bisect-state \$state' exited with error code \$res" >&2
-			exit $res
-		fi
-
-		if sane_grep "is the first $TERM_BAD commit" "$GIT_DIR/BISECT_RUN" >/dev/null
-		then
-			gettextln "bisect run success"
-			exit 0;
-		fi
-
-	done
-}
-
 get_terms () {
 	if test -s "$GIT_DIR/BISECT_TERMS"
 	then
@@ -137,7 +77,7 @@  case "$#" in
 	log)
 		git bisect--helper --bisect-log || exit ;;
 	run)
-		bisect_run "$@" ;;
+		git bisect--helper --bisect-run "$@" || exit;;
 	terms)
 		git bisect--helper --bisect-terms "$@" || exit;;
 	*)