[PATCH v5 0/6] Finish converting git bisect to C part 4

[PATCH v5 0/6] Finish converting git bisect to C part 4

[Miriam Rubio]

These patches correspond to a fourth part of patch series 
of Outreachy project "Finish converting `git bisect` from shell to C" 
started by Pranit Bauva and Tanushree Tumane
(https://public-inbox.org/git/pull.117.git.gitgitgadget@gmail.com) and
continued by me.

This fourth part is formed by reimplementations of some `git bisect` 
subcommands, addition of tests and removal of some temporary subcommands.

These patch series emails were generated from:
https://gitlab.com/mirucam/git/commits/git-bisect-work-part4-v5.

I would like to thank Johannes Schindelin, Bagas Sanjaya and 
Christian Couder for reviewing this patch series.

Specific changes
----------------
[1/6] t6030-bisect-porcelain: add tests to control bisect run exit cases
* Add evaluation of error code 255 in test 'bisect run fails with exit 
code equals or greater than 128'.
* Remove test with error code smaller than 0.
---

[4/6] bisect--helper: reimplement `bisect_visualize()`shell function in C
* Use strvec_push() instead of strvec_pushl().
---

[5/6] bisect--helper: reimplement `bisect_run` shell function in C
* Add error message.
* Remove exit variable.
* Write contents of bisect_state() in BISECT_RUN file and show to user.
---

Miriam Rubio (3):
  t6030-bisect-porcelain: add tests to control bisect run exit cases
  t6030-bisect-porcelain: add test for bisect visualize
  bisect--helper: retire `--bisect-next-check` subcommand

Pranit Bauva (2):
  run-command: make `exists_in_PATH()` non-static
  bisect--helper: reimplement `bisect_visualize()`shell function in C

Tanushree Tumane (1):
  bisect--helper: reimplement `bisect_run` shell function in C

 builtin/bisect--helper.c    | 157 ++++++++++++++++++++++++++++++++++--
 git-bisect.sh               |  87 +-------------------
 run-command.c               |   2 +-
 run-command.h               |  12 +++
 t/t6030-bisect-porcelain.sh |  18 +++++
 5 files changed, 182 insertions(+), 94 deletions(-)

-- 
2.29.2

[PATCH v5 1/6] t6030-bisect-porcelain: add tests to control bisect run exit cases

[Miriam Rubio]

There is a gap on bisect run test coverage related with error exits.
Add two tests to control these error cases.

Signed-off-by: Miriam Rubio <mirucam@gmail.com>
---
 t/t6030-bisect-porcelain.sh | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/t/t6030-bisect-porcelain.sh b/t/t6030-bisect-porcelain.sh
index a1baf4e451..e61b8143fd 100755
--- a/t/t6030-bisect-porcelain.sh
+++ b/t/t6030-bisect-porcelain.sh
@@ -962,4 +962,15 @@ test_expect_success 'bisect handles annotated tags' '
 	grep "$bad is the first bad commit" output
 '
 
+test_expect_success 'bisect run fails with exit code equals or greater than 128' '
+	write_script test_script.sh <<-\EOF &&
+	exit 128 >/dev/null
+	EOF
+	test_must_fail git bisect run ./test_script.sh > my_bisect_log.txt &&
+	write_script test_script.sh <<-\EOF &&
+	exit 255 >/dev/null
+	EOF
+	test_must_fail git bisect run ./test_script.sh >> my_bisect_log.txt
+'
+
 test_done
-- 
2.29.2

[PATCH v5 2/6] t6030-bisect-porcelain: add test for bisect visualize

[Miriam Rubio]

Add a test to control breakages in bisect visualize command.

Signed-off-by: Miriam Rubio <mirucam@gmail.com>
---
 t/t6030-bisect-porcelain.sh | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/t/t6030-bisect-porcelain.sh b/t/t6030-bisect-porcelain.sh
index e61b8143fd..f13eeac9ce 100755
--- a/t/t6030-bisect-porcelain.sh
+++ b/t/t6030-bisect-porcelain.sh
@@ -973,4 +973,11 @@ test_expect_success 'bisect run fails with exit code equals or greater than 128'
 	test_must_fail git bisect run ./test_script.sh >> my_bisect_log.txt
 '
 
+test_expect_success 'bisect visualize with a filename with dash and space' '
+	echo "My test line" >> -hello\ 2 &&
+	git add -- -hello\ 2 &&
+	git commit --quiet -m "Add test line" -- -hello\ 2 &&
+	git bisect visualize -p -- -hello\ 2 > my_bisect_log.txt
+'
+
 test_done
-- 
2.29.2

[PATCH v5 3/6] run-command: make `exists_in_PATH()` non-static

[Miriam Rubio]

From: Pranit Bauva <pranit.bauva@gmail.com>

Removes the `static` keyword from `exists_in_PATH()` function
and declares the function in `run-command.h` file.
The function will be used in bisect_visualize() in a later
commit.

Mentored by: Christian Couder <chriscool@tuxfamily.org>
Mentored by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Signed-off-by: Tanushree Tumane <tanushreetumane@gmail.com>
Signed-off-by: Miriam Rubio <mirucam@gmail.com>
---
 run-command.c |  2 +-
 run-command.h | 12 ++++++++++++
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/run-command.c b/run-command.c
index f72e72cce7..390f46819f 100644
--- a/run-command.c
+++ b/run-command.c
@@ -210,7 +210,7 @@ static char *locate_in_PATH(const char *file)
 	return NULL;
 }
 
-static int exists_in_PATH(const char *file)
+int exists_in_PATH(const char *file)
 {
 	char *r = locate_in_PATH(file);
 	int found = r != NULL;
diff --git a/run-command.h b/run-command.h
index af1296769f..54d74b706f 100644
--- a/run-command.h
+++ b/run-command.h
@@ -182,6 +182,18 @@ void child_process_clear(struct child_process *);
 
 int is_executable(const char *name);
 
+/**
+ * Search if a $PATH for a command exists.  This emulates the path search that
+ * execvp would perform, without actually executing the command so it
+ * can be used before fork() to prepare to run a command using
+ * execve() or after execvp() to diagnose why it failed.
+ *
+ * The caller should ensure that file contains no directory separators.
+ *
+ * Returns 1 if it is found in $PATH or 0 if the command could not be found.
+ */
+int exists_in_PATH(const char *file);
+
 /**
  * Start a sub-process. Takes a pointer to a `struct child_process`
  * that specifies the details and returns pipe FDs (if requested).
-- 
2.29.2

[PATCH v5 4/6] bisect--helper: reimplement `bisect_visualize()`shell function in C

[Miriam Rubio]

From: Pranit Bauva <pranit.bauva@gmail.com>

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

Mentored-by: Christian Couder <chriscool@tuxfamily.org>
Mentored-by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Signed-off-by: Tanushree Tumane <tanushreetumane@gmail.com>
Signed-off-by: Miriam Rubio <mirucam@gmail.com>
---
 builtin/bisect--helper.c | 48 +++++++++++++++++++++++++++++++++++++++-
 git-bisect.sh            | 25 +--------------------
 2 files changed, 48 insertions(+), 25 deletions(-)

diff --git a/builtin/bisect--helper.c b/builtin/bisect--helper.c
index f184eaeac6..1e118a966a 100644
--- a/builtin/bisect--helper.c
+++ b/builtin/bisect--helper.c
@@ -30,6 +30,7 @@ static const char * const git_bisect_helper_usage[] = {
 	N_("git bisect--helper --bisect-state (good|old) [<rev>...]"),
 	N_("git bisect--helper --bisect-replay <filename>"),
 	N_("git bisect--helper --bisect-skip [(<rev>|<range>)...]"),
+	N_("git bisect--helper --bisect-visualize"),
 	NULL
 };
 
@@ -1036,6 +1037,44 @@ static enum bisect_error bisect_skip(struct bisect_terms *terms, const char **ar
 	return res;
 }
 
+static int bisect_visualize(struct bisect_terms *terms, const char **argv, int argc)
+{
+	struct strvec args = STRVEC_INIT;
+	int flags = RUN_COMMAND_NO_STDIN, res = 0;
+	struct strbuf sb = STRBUF_INIT;
+
+	if (bisect_next_check(terms, NULL) != 0)
+		return BISECT_FAILED;
+
+	if (!argc) {
+		if ((getenv("DISPLAY") || getenv("SESSIONNAME") || getenv("MSYSTEM") ||
+		     getenv("SECURITYSESSIONID")) && exists_in_PATH("gitk"))
+			strvec_push(&args, "gitk");
+		else {
+			strvec_push(&args, "log");
+			flags |= RUN_GIT_CMD;
+		}
+	} else {
+		if (argv[0][0] == '-') {
+			strvec_push(&args, "log");
+			flags |= RUN_GIT_CMD;
+		} else if (strcmp(argv[0], "tig") && !starts_with(argv[0], "git"))
+			flags |= RUN_GIT_CMD;
+
+		strvec_pushv(&args, argv);
+	}
+
+	strvec_pushl(&args, "--bisect", "--", NULL);
+
+	strbuf_read_file(&sb, git_path_bisect_names(), 0);
+	sq_dequote_to_strvec(sb.buf, &args);
+	strbuf_release(&sb);
+
+	res = run_command_v_opt(args.v, flags);
+	strvec_clear(&args);
+	return res;
+}
+
 int cmd_bisect__helper(int argc, const char **argv, const char *prefix)
 {
 	enum {
@@ -1048,7 +1087,8 @@ int cmd_bisect__helper(int argc, const char **argv, const char *prefix)
 		BISECT_STATE,
 		BISECT_LOG,
 		BISECT_REPLAY,
-		BISECT_SKIP
+		BISECT_SKIP,
+		BISECT_VISUALIZE,
 	} cmdmode = 0;
 	int res = 0, nolog = 0;
 	struct option options[] = {
@@ -1070,6 +1110,8 @@ int cmd_bisect__helper(int argc, const char **argv, const char *prefix)
 			 N_("replay the bisection process from the given file"), BISECT_REPLAY),
 		OPT_CMDMODE(0, "bisect-skip", &cmdmode,
 			 N_("skip some commits for checkout"), BISECT_SKIP),
+		OPT_CMDMODE(0, "bisect-visualize", &cmdmode,
+			 N_("visualize the bisection"), BISECT_VISUALIZE),
 		OPT_BOOL(0, "no-log", &nolog,
 			 N_("no log for BISECT_WRITE")),
 		OPT_END()
@@ -1131,6 +1173,10 @@ int cmd_bisect__helper(int argc, const char **argv, const char *prefix)
 		get_terms(&terms);
 		res = bisect_skip(&terms, argv, argc);
 		break;
+	case BISECT_VISUALIZE:
+		get_terms(&terms);
+		res = bisect_visualize(&terms, argv, argc);
+		break;
 	default:
 		BUG("unknown subcommand %d", cmdmode);
 	}
diff --git a/git-bisect.sh b/git-bisect.sh
index 6a7afaea8d..95f7f3fb8c 100755
--- a/git-bisect.sh
+++ b/git-bisect.sh
@@ -39,29 +39,6 @@ _x40="$_x40$_x40$_x40$_x40$_x40$_x40$_x40$_x40"
 TERM_BAD=bad
 TERM_GOOD=good
 
-bisect_visualize() {
-	git bisect--helper --bisect-next-check $TERM_GOOD $TERM_BAD fail || exit
-
-	if test $# = 0
-	then
-		if test -n "${DISPLAY+set}${SESSIONNAME+set}${MSYSTEM+set}${SECURITYSESSIONID+set}" &&
-			type gitk >/dev/null 2>&1
-		then
-			set gitk
-		else
-			set git log
-		fi
-	else
-		case "$1" in
-		git*|tig) ;;
-		-*)	set git log "$@" ;;
-		*)	set git "$@" ;;
-		esac
-	fi
-
-	eval '"$@"' --bisect -- $(cat "$GIT_DIR/BISECT_NAMES")
-}
-
 bisect_run () {
 	git bisect--helper --bisect-next-check $TERM_GOOD $TERM_BAD fail || exit
 
@@ -152,7 +129,7 @@ case "$#" in
 		# Not sure we want "next" at the UI level anymore.
 		git bisect--helper --bisect-next "$@" || exit ;;
 	visualize|view)
-		bisect_visualize "$@" ;;
+		git bisect--helper --bisect-visualize "$@" || exit;;
 	reset)
 		git bisect--helper --bisect-reset "$@" ;;
 	replay)
-- 
2.29.2

[PATCH v5 5/6] bisect--helper: reimplement `bisect_run` shell function in C

[Miriam Rubio]

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 | 102 +++++++++++++++++++++++++++++++++++++++
 git-bisect.sh            |  62 +-----------------------
 2 files changed, 103 insertions(+), 61 deletions(-)

diff --git a/builtin/bisect--helper.c b/builtin/bisect--helper.c
index 1e118a966a..8d33c809aa 100644
--- a/builtin/bisect--helper.c
+++ b/builtin/bisect--helper.c
@@ -18,6 +18,7 @@ static GIT_PATH_FUNC(git_path_bisect_log, "BISECT_LOG")
 static GIT_PATH_FUNC(git_path_head_name, "head-name")
 static GIT_PATH_FUNC(git_path_bisect_names, "BISECT_NAMES")
 static GIT_PATH_FUNC(git_path_bisect_first_parent, "BISECT_FIRST_PARENT")
+static GIT_PATH_FUNC(git_path_bisect_run, "BISECT_RUN")
 
 static const char * const git_bisect_helper_usage[] = {
 	N_("git bisect--helper --bisect-reset [<commit>]"),
@@ -31,6 +32,7 @@ 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
 };
 
@@ -144,6 +146,25 @@ static int append_to_file(const char *path, const char *format, ...)
 	return res;
 }
 
+static int print_file_to_stdout(const char *path)
+{
+	FILE *fp;
+	char c;
+
+	fp = fopen(path, "r");
+	if (!fp)
+		return error_errno(_("cannot open file '%s' in read mode"), path);
+
+	c = fgetc(fp);
+	while (c != EOF) {
+		printf ("%c", c);
+		c = fgetc(fp);
+	}
+
+	fclose(fp);
+	return 0;
+}
+
 static int check_term_format(const char *term, const char *orig_term)
 {
 	int res;
@@ -1075,6 +1096,78 @@ 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;
+	const char *new_state;
+	int temporary_stdout_fd, saved_stdout;
+
+	if (bisect_next_check(terms, NULL))
+		return BISECT_FAILED;
+
+	if (argc)
+		sq_quote_argv(&command, argv);
+	else {
+		error(_("bisect run failed: no command provided."));
+		return BISECT_FAILED;
+	}
+
+	strvec_push(&run_args, command.buf);
+
+	while (1) {
+		strvec_clear(&args);
+
+		printf(_("running %s\n"), command.buf);
+		res = run_command_v_opt(run_args.v, RUN_USING_SHELL);
+
+		if (res < 0 || 128 <= res) {
+			error(_("bisect run failed: exit code %d from"
+				" '%s' is < 0 or >= 128"), res, command.buf);
+			strbuf_release(&command);
+			return res;
+		}
+
+		if (res == 125)
+			new_state = "skip";
+		else new_state = res > 0 ? terms->term_bad : terms->term_good;
+
+		temporary_stdout_fd = open(git_path_bisect_run(), O_CREAT | O_WRONLY | O_TRUNC, 0666);
+		saved_stdout = dup(1);
+		dup2(temporary_stdout_fd, 1);
+
+		res = bisect_state(terms, &new_state, 1);
+
+		dup2(saved_stdout, 1);
+		close(saved_stdout);
+		close(temporary_stdout_fd);
+
+		print_file_to_stdout(git_path_bisect_run());
+
+		if (res == BISECT_ONLY_SKIPPED_LEFT)
+			error(_("bisect run cannot continue any more"));
+		else if (res == BISECT_INTERNAL_SUCCESS_MERGE_BASE) {
+			printf(_("bisect run success"));
+			res = BISECT_OK;
+		} else if (res == BISECT_INTERNAL_SUCCESS_1ST_BAD_FOUND) {
+			printf(_("bisect found first bad commit"));
+			res = BISECT_OK;
+		} 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 {
@@ -1089,6 +1182,7 @@ int cmd_bisect__helper(int argc, const char **argv, const char *prefix)
 		BISECT_REPLAY,
 		BISECT_SKIP,
 		BISECT_VISUALIZE,
+		BISECT_RUN,
 	} cmdmode = 0;
 	int res = 0, nolog = 0;
 	struct option options[] = {
@@ -1112,6 +1206,8 @@ 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()
@@ -1177,6 +1273,12 @@ 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;;
 	*)
-- 
2.29.2

[PATCH v5 6/6] bisect--helper: retire `--bisect-next-check` subcommand

[Miriam Rubio]

After reimplementation of `git bisect run` in C,
`--bisect-next-check` subcommand is not needed anymore.

Let's remove it from options list and code.

Mentored by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Miriam Rubio <mirucam@gmail.com>
---
 builtin/bisect--helper.c | 7 -------
 1 file changed, 7 deletions(-)

diff --git a/builtin/bisect--helper.c b/builtin/bisect--helper.c
index 8d33c809aa..6e1e7c243d 100644
--- a/builtin/bisect--helper.c
+++ b/builtin/bisect--helper.c
@@ -22,7 +22,6 @@ static GIT_PATH_FUNC(git_path_bisect_run, "BISECT_RUN")
 
 static const char * const git_bisect_helper_usage[] = {
 	N_("git bisect--helper --bisect-reset [<commit>]"),
-	N_("git bisect--helper --bisect-next-check <good_term> <bad_term> [<term>]"),
 	N_("git bisect--helper --bisect-terms [--term-good | --term-old | --term-bad | --term-new]"),
 	N_("git bisect--helper --bisect-start [--term-{new,bad}=<term> --term-{old,good}=<term>]"
 					    " [--no-checkout] [--first-parent] [<bad> [<good>...]] [--] [<paths>...]"),
@@ -1227,12 +1226,6 @@ int cmd_bisect__helper(int argc, const char **argv, const char *prefix)
 			return error(_("--bisect-reset requires either no argument or a commit"));
 		res = bisect_reset(argc ? argv[0] : NULL);
 		break;
-	case BISECT_NEXT_CHECK:
-		if (argc != 2 && argc != 3)
-			return error(_("--bisect-next-check requires 2 or 3 arguments"));
-		set_terms(&terms, argv[1], argv[0]);
-		res = bisect_next_check(&terms, argc == 3 ? argv[2] : NULL);
-		break;
 	case BISECT_TERMS:
 		if (argc > 1)
 			return error(_("--bisect-terms requires 0 or 1 argument"));
-- 
2.29.2

Re: [PATCH v5 5/6] bisect--helper: reimplement `bisect_run` shell function in C

[Johannes Schindelin]

Hi Miriam,

On Fri, 20 Aug 2021, Miriam Rubio wrote:

> 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 | 102 +++++++++++++++++++++++++++++++++++++++
>  git-bisect.sh            |  62 +-----------------------
>  2 files changed, 103 insertions(+), 61 deletions(-)
>
> diff --git a/builtin/bisect--helper.c b/builtin/bisect--helper.c
> index 1e118a966a..8d33c809aa 100644
> --- a/builtin/bisect--helper.c
> +++ b/builtin/bisect--helper.c
> @@ -18,6 +18,7 @@ static GIT_PATH_FUNC(git_path_bisect_log, "BISECT_LOG")
>  static GIT_PATH_FUNC(git_path_head_name, "head-name")
>  static GIT_PATH_FUNC(git_path_bisect_names, "BISECT_NAMES")
>  static GIT_PATH_FUNC(git_path_bisect_first_parent, "BISECT_FIRST_PARENT")
> +static GIT_PATH_FUNC(git_path_bisect_run, "BISECT_RUN")
>
>  static const char * const git_bisect_helper_usage[] = {
>  	N_("git bisect--helper --bisect-reset [<commit>]"),
> @@ -31,6 +32,7 @@ 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
>  };
>
> @@ -144,6 +146,25 @@ static int append_to_file(const char *path, const char *format, ...)
>  	return res;
>  }
>
> +static int print_file_to_stdout(const char *path)
> +{
> +	FILE *fp;
> +	char c;
> +
> +	fp = fopen(path, "r");
> +	if (!fp)
> +		return error_errno(_("cannot open file '%s' in read mode"), path);
> +
> +	c = fgetc(fp);
> +	while (c != EOF) {
> +		printf ("%c", c);
> +		c = fgetc(fp);
> +	}
> +
> +	fclose(fp);

Rather than reading byte for byte (even if buffered), how about using
`copy_fd()`? Something like

	int fd = open(path, O_RDONLY), ret = 0;

	if (fd < 0)
		return error_errno(_("cannot open file '%s' for reading"), path);
	if (copy_fd(fd, 1) < 0)
		ret = error_errno(_("failed to read '%s'"), path);
	close(fd);
	return ret;

> +	return 0;
> +}
> +
>  static int check_term_format(const char *term, const char *orig_term)
>  {
>  	int res;
> @@ -1075,6 +1096,78 @@ 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;
> +	const char *new_state;
> +	int temporary_stdout_fd, saved_stdout;
> +
> +	if (bisect_next_check(terms, NULL))
> +		return BISECT_FAILED;
> +
> +	if (argc)
> +		sq_quote_argv(&command, argv);
> +	else {
> +		error(_("bisect run failed: no command provided."));
> +		return BISECT_FAILED;
> +	}
> +
> +	strvec_push(&run_args, command.buf);
> +
> +	while (1) {
> +		strvec_clear(&args);
> +
> +		printf(_("running %s\n"), command.buf);
> +		res = run_command_v_opt(run_args.v, RUN_USING_SHELL);
> +
> +		if (res < 0 || 128 <= res) {
> +			error(_("bisect run failed: exit code %d from"
> +				" '%s' is < 0 or >= 128"), res, command.buf);
> +			strbuf_release(&command);
> +			return res;
> +		}
> +
> +		if (res == 125)
> +			new_state = "skip";
> +		else new_state = res > 0 ? terms->term_bad : terms->term_good;

I do not care _all_ that much about formatting, but I think others on this
list do, and might point out that the `else` wants to live on its own
line.

> +		temporary_stdout_fd = open(git_path_bisect_run(), O_CREAT | O_WRONLY | O_TRUNC, 0666);
> +		saved_stdout = dup(1);
> +		dup2(temporary_stdout_fd, 1);

This temporary redirection looks a bit iffy. I wonder whether there is a
way to tell `bisect_state()` to print to a given file descriptor, _in
addition to_ `stdout`? That would also make `print_file_to_stdout()`
obsolete.

What calls exactly are making that print to `stdout` anyway?

This is my only remaining issue with the current 5/6.

Thank you,
Dscho

> +
> +		res = bisect_state(terms, &new_state, 1);
> +
> +		dup2(saved_stdout, 1);
> +		close(saved_stdout);
> +		close(temporary_stdout_fd);
> +
> +		print_file_to_stdout(git_path_bisect_run());
> +
> +		if (res == BISECT_ONLY_SKIPPED_LEFT)
> +			error(_("bisect run cannot continue any more"));
> +		else if (res == BISECT_INTERNAL_SUCCESS_MERGE_BASE) {
> +			printf(_("bisect run success"));
> +			res = BISECT_OK;
> +		} else if (res == BISECT_INTERNAL_SUCCESS_1ST_BAD_FOUND) {
> +			printf(_("bisect found first bad commit"));
> +			res = BISECT_OK;
> +		} 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 {
> @@ -1089,6 +1182,7 @@ int cmd_bisect__helper(int argc, const char **argv, const char *prefix)
>  		BISECT_REPLAY,
>  		BISECT_SKIP,
>  		BISECT_VISUALIZE,
> +		BISECT_RUN,
>  	} cmdmode = 0;
>  	int res = 0, nolog = 0;
>  	struct option options[] = {
> @@ -1112,6 +1206,8 @@ 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()
> @@ -1177,6 +1273,12 @@ 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;;
>  	*)
> --
> 2.29.2
>
>

Re: [PATCH v5 0/6] Finish converting git bisect to C part 4

[Johannes Schindelin]

Hi Miriam,

On Fri, 20 Aug 2021, Miriam Rubio wrote:

> These patches correspond to a fourth part of patch series
> of Outreachy project "Finish converting `git bisect` from shell to C"
> started by Pranit Bauva and Tanushree Tumane
> (https://public-inbox.org/git/pull.117.git.gitgitgadget@gmail.com) and
> continued by me.
>
> This fourth part is formed by reimplementations of some `git bisect`
> subcommands, addition of tests and removal of some temporary subcommands.
>
> These patch series emails were generated from:
> https://gitlab.com/mirucam/git/commits/git-bisect-work-part4-v5.

Apart from the stdout redirection in 5/6, the patches look really stable
to me.

Thanks,
Dscho

>
> I would like to thank Johannes Schindelin, Bagas Sanjaya and
> Christian Couder for reviewing this patch series.
>
> Specific changes
> ----------------
> [1/6] t6030-bisect-porcelain: add tests to control bisect run exit cases
> * Add evaluation of error code 255 in test 'bisect run fails with exit
> code equals or greater than 128'.
> * Remove test with error code smaller than 0.
> ---
>
> [4/6] bisect--helper: reimplement `bisect_visualize()`shell function in C
> * Use strvec_push() instead of strvec_pushl().
> ---
>
> [5/6] bisect--helper: reimplement `bisect_run` shell function in C
> * Add error message.
> * Remove exit variable.
> * Write contents of bisect_state() in BISECT_RUN file and show to user.
> ---
>
> Miriam Rubio (3):
>   t6030-bisect-porcelain: add tests to control bisect run exit cases
>   t6030-bisect-porcelain: add test for bisect visualize
>   bisect--helper: retire `--bisect-next-check` subcommand
>
> Pranit Bauva (2):
>   run-command: make `exists_in_PATH()` non-static
>   bisect--helper: reimplement `bisect_visualize()`shell function in C
>
> Tanushree Tumane (1):
>   bisect--helper: reimplement `bisect_run` shell function in C
>
>  builtin/bisect--helper.c    | 157 ++++++++++++++++++++++++++++++++++--
>  git-bisect.sh               |  87 +-------------------
>  run-command.c               |   2 +-
>  run-command.h               |  12 +++
>  t/t6030-bisect-porcelain.sh |  18 +++++
>  5 files changed, 182 insertions(+), 94 deletions(-)
>
> --
> 2.29.2
>
>

Re: [PATCH v5 5/6] bisect--helper: reimplement `bisect_run` shell function in C

[Miriam R.]

Hi Johannes,


El mar, 24 ago 2021 a las 15:59, Johannes Schindelin
(<Johannes.Schindelin@gmx.de>) escribió:
>
> Hi Miriam,
>
> On Fri, 20 Aug 2021, Miriam Rubio wrote:
>
> > 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 | 102 +++++++++++++++++++++++++++++++++++++++
> >  git-bisect.sh            |  62 +-----------------------
> >  2 files changed, 103 insertions(+), 61 deletions(-)
> >
> > diff --git a/builtin/bisect--helper.c b/builtin/bisect--helper.c
> > index 1e118a966a..8d33c809aa 100644
> > --- a/builtin/bisect--helper.c
> > +++ b/builtin/bisect--helper.c
> > @@ -18,6 +18,7 @@ static GIT_PATH_FUNC(git_path_bisect_log, "BISECT_LOG")
> >  static GIT_PATH_FUNC(git_path_head_name, "head-name")
> >  static GIT_PATH_FUNC(git_path_bisect_names, "BISECT_NAMES")
> >  static GIT_PATH_FUNC(git_path_bisect_first_parent, "BISECT_FIRST_PARENT")
> > +static GIT_PATH_FUNC(git_path_bisect_run, "BISECT_RUN")
> >
> >  static const char * const git_bisect_helper_usage[] = {
> >       N_("git bisect--helper --bisect-reset [<commit>]"),
> > @@ -31,6 +32,7 @@ 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
> >  };
> >
> > @@ -144,6 +146,25 @@ static int append_to_file(const char *path, const char *format, ...)
> >       return res;
> >  }
> >
> > +static int print_file_to_stdout(const char *path)
> > +{
> > +     FILE *fp;
> > +     char c;
> > +
> > +     fp = fopen(path, "r");
> > +     if (!fp)
> > +             return error_errno(_("cannot open file '%s' in read mode"), path);
> > +
> > +     c = fgetc(fp);
> > +     while (c != EOF) {
> > +             printf ("%c", c);
> > +             c = fgetc(fp);
> > +     }
> > +
> > +     fclose(fp);
>
> Rather than reading byte for byte (even if buffered), how about using
> `copy_fd()`? Something like
>
>         int fd = open(path, O_RDONLY), ret = 0;
>
>         if (fd < 0)
>                 return error_errno(_("cannot open file '%s' for reading"), path);
>         if (copy_fd(fd, 1) < 0)
>                 ret = error_errno(_("failed to read '%s'"), path);
>         close(fd);
>         return ret;
>
Ok. Noted.
> > +     return 0;
> > +}
> > +
> >  static int check_term_format(const char *term, const char *orig_term)
> >  {
> >       int res;
> > @@ -1075,6 +1096,78 @@ 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;
> > +     const char *new_state;
> > +     int temporary_stdout_fd, saved_stdout;
> > +
> > +     if (bisect_next_check(terms, NULL))
> > +             return BISECT_FAILED;
> > +
> > +     if (argc)
> > +             sq_quote_argv(&command, argv);
> > +     else {
> > +             error(_("bisect run failed: no command provided."));
> > +             return BISECT_FAILED;
> > +     }
> > +
> > +     strvec_push(&run_args, command.buf);
> > +
> > +     while (1) {
> > +             strvec_clear(&args);
> > +
> > +             printf(_("running %s\n"), command.buf);
> > +             res = run_command_v_opt(run_args.v, RUN_USING_SHELL);
> > +
> > +             if (res < 0 || 128 <= res) {
> > +                     error(_("bisect run failed: exit code %d from"
> > +                             " '%s' is < 0 or >= 128"), res, command.buf);
> > +                     strbuf_release(&command);
> > +                     return res;
> > +             }
> > +
> > +             if (res == 125)
> > +                     new_state = "skip";
> > +             else new_state = res > 0 ? terms->term_bad : terms->term_good;
>
> I do not care _all_ that much about formatting, but I think others on this
> list do, and might point out that the `else` wants to live on its own
> line.
Ok. I'll change that.
>
> > +             temporary_stdout_fd = open(git_path_bisect_run(), O_CREAT | O_WRONLY | O_TRUNC, 0666);
> > +             saved_stdout = dup(1);
> > +             dup2(temporary_stdout_fd, 1);
>
> This temporary redirection looks a bit iffy. I wonder whether there is a
> way to tell `bisect_state()` to print to a given file descriptor, _in
> addition to_ `stdout`? That would also make `print_file_to_stdout()`
> obsolete.
>
> What calls exactly are making that print to `stdout` anyway?

I was trying to recreate the cat command with this solution as it is
in the shell script, without changing behavior or parameters in other
functions.
I think the most important prints to stdout come from
bisect_next_all() in bisect.c. The sequence is bisect_state()
->bisect_auto_next() ->  bisect_next() ->bisect_next_all().
Just to clarify: if we add a file descriptor as parameter in
bisect_state(), we have to propagate it to a lot of functions, is that
what we want?

>
> This is my only remaining issue with the current 5/6.
Thank you for reviewing!
Miriam
>
> Thank you,
> Dscho
>
> > +
> > +             res = bisect_state(terms, &new_state, 1);
> > +
> > +             dup2(saved_stdout, 1);
> > +             close(saved_stdout);
> > +             close(temporary_stdout_fd);
> > +
> > +             print_file_to_stdout(git_path_bisect_run());
> > +
> > +             if (res == BISECT_ONLY_SKIPPED_LEFT)
> > +                     error(_("bisect run cannot continue any more"));
> > +             else if (res == BISECT_INTERNAL_SUCCESS_MERGE_BASE) {
> > +                     printf(_("bisect run success"));
> > +                     res = BISECT_OK;
> > +             } else if (res == BISECT_INTERNAL_SUCCESS_1ST_BAD_FOUND) {
> > +                     printf(_("bisect found first bad commit"));
> > +                     res = BISECT_OK;
> > +             } 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 {
> > @@ -1089,6 +1182,7 @@ int cmd_bisect__helper(int argc, const char **argv, const char *prefix)
> >               BISECT_REPLAY,
> >               BISECT_SKIP,
> >               BISECT_VISUALIZE,
> > +             BISECT_RUN,
> >       } cmdmode = 0;
> >       int res = 0, nolog = 0;
> >       struct option options[] = {
> > @@ -1112,6 +1206,8 @@ 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()
> > @@ -1177,6 +1273,12 @@ 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;;
> >       *)
> > --
> > 2.29.2
> >
> >