[GSoC] Update: Week 6

[GSoC] Update: Week 6

[Prathamesh Chavan]

SUMMARY OF MY PROJECT:

Git submodule subcommands are currently implemented by using shell script
'git-submodule.sh'. There are several reasons why we'll prefer not to
use the shell script. My project intends to convert the subcommands into
C code, thus making them builtins. This will increase Git's portability
and hence the efficiency of working with the git-submodule commands.
Link to the complete proposal: [1]

Mentors:
Stefan Beller <sbeller@google.com>
Christian Couder <christian.couder@gmail.com>

UPDATES:

Following are the updates about my ongoing project:

1. sync and status: The patches were discussed with the mentors
   and after that, are being posted with this patch.

2. deinit: The patch is debugged, and is ready to be
   discussed. Not much discussion occurred over this patch
   and hence the patch is same as its previous version.
   It is also attached with this update.

3. summary: The porting of this submodule subcommand is
   almost completed. Things like improving the function
   names, checking for memory leakage, etc are still
   left to be taken care of. I'm updating the patch's status
   by sending the patch to the mentors off-list, so that
   an appropriate version is posted here on the list.
   Hence, it wasn't attached to the update.

4. foreach: Not much progress was done with this patch
   in particular as most of the time was used for completing
   the porting of submodule subcommand 'summary'.
   Hence its status remains same as mentioned in the
   previous update, which is reposted below:
   'As stated in the previous update, the subcommand was
   ported without resolving the bug, and simply translating the
   present code, and adding a NEEDSWORK tag to the comment for
   mentioning the reported bug as well.
   But as communicating between child_process is still an issue
   and so there was no simple was to current carry out the
   porting. And hence, a hack was used instead. But after
   discussing it, instead using the repository-object patch
   series will help to resolve these issues in this situation.'

PLAN FOR WEEK-7 (27 June 2017 to 3 July 2017):

1. foreach: Since the required changes weren't made in the last
   week in regards with this patch, in the next week I aim for
   fulfilling them first. I'll like to again mention it here:
   As it was decided that unblock the conversion of
   this submodule subcommand, the original cmd_foreach was
   ported without including the BUG-FIX patch here.
   Hence, for this week I will try to utilize the
   'repository-object' series by Brandon Williams.
   Additionally, I'll like to mention that this update
   still, doesn't depend on the 'repository-object' series,
   which I'll be trying to change in the next update.

2. summary: As mentioned earlier, since there is still a little
   work with its porting left, I'll try to finish it and debug
   the ported code as well.

3. deinit: As there is still scope of improvision and discussion
   I'll also be focussing on improving this patch.

[1]: https://docs.google.com/document/d/1krxVLooWl--75Pot3dazhfygR3wCUUWZWzTXtK1L-xU/

Thanks,
Prathamesh Chavan

[GSoC][PATCH 1/6 v2] submodule--helper: introduce for_each_submodule_list

[Prathamesh Chavan]

Introduce function for_each_submodule_list for using it
in the later patches, related to porting submodule
subcommands from shell to C.
This new function is also used in ported submodule subcommand
init.

Mentored-by: Christian Couder <christian.couder@gmail.com>
Mentored-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Prathamesh Chavan <pc44800@gmail.com>
---
This series of patches is based on the 'next' branch. 

Complete build report of this patch series is available at:
https://travis-ci.org/pratham-pc/git/builds/
Branch: patch-series
Build #113

 builtin/submodule--helper.c | 39 +++++++++++++++++++++++++++++----------
 1 file changed, 29 insertions(+), 10 deletions(-)

diff --git a/builtin/submodule--helper.c b/builtin/submodule--helper.c
index 1bfc91bca..c4286aac5 100644
--- a/builtin/submodule--helper.c
+++ b/builtin/submodule--helper.c
@@ -14,6 +14,9 @@
 #include "refs.h"
 #include "connect.h"
 
+typedef void (*submodule_list_func_t)(const struct cache_entry *list_item,
+				      void *cb_data);
+
 static char *get_default_remote(void)
 {
 	char *dest = NULL, *ret;
@@ -352,17 +355,30 @@ static int module_list(int argc, const char **argv, const char *prefix)
 	return 0;
 }
 
-static void init_submodule(const char *path, const char *prefix, int quiet)
+static void for_each_submodule_list(const struct module_list list,
+				    submodule_list_func_t fn, void *cb_data)
 {
+	int i;
+	for (i = 0; i < list.nr; i++)
+		fn(list.entries[i], cb_data);
+}
+
+struct init_cb {
+	const char *prefix;
+	unsigned int quiet: 1;
+};
+#define INIT_CB_INIT { NULL, 0 }
+
+static void init_submodule(const struct cache_entry *list_item, void *cb_data)
+{
+	struct init_cb *info = cb_data;
 	const struct submodule *sub;
 	struct strbuf sb = STRBUF_INIT;
 	char *upd = NULL, *url = NULL, *displaypath;
 
-	/* Only loads from .gitmodules, no overlay with .git/config */
-	gitmodules_config();
-	displaypath = get_submodule_displaypath(path, prefix);
+	displaypath = get_submodule_displaypath(list_item->name, info->prefix);
 
-	sub = submodule_from_path(null_sha1, path);
+	sub = submodule_from_path(null_sha1, list_item->name);
 
 	if (!sub)
 		die(_("No url found for submodule path '%s' in .gitmodules"),
@@ -374,7 +390,7 @@ static void init_submodule(const char *path, const char *prefix, int quiet)
 	 *
 	 * Set active flag for the submodule being initialized
 	 */
-	if (!is_submodule_initialized(path)) {
+	if (!is_submodule_initialized(list_item->name)) {
 		strbuf_addf(&sb, "submodule.%s.active", sub->name);
 		git_config_set_gently(sb.buf, "true");
 	}
@@ -416,7 +432,7 @@ static void init_submodule(const char *path, const char *prefix, int quiet)
 		if (git_config_set_gently(sb.buf, url))
 			die(_("Failed to register url for submodule path '%s'"),
 			    displaypath);
-		if (!quiet)
+		if (!info->quiet)
 			fprintf(stderr,
 				_("Submodule '%s' (%s) registered for path '%s'\n"),
 				sub->name, url, displaypath);
@@ -445,10 +461,10 @@ static void init_submodule(const char *path, const char *prefix, int quiet)
 
 static int module_init(int argc, const char **argv, const char *prefix)
 {
+	struct init_cb info = INIT_CB_INIT;
 	struct pathspec pathspec;
 	struct module_list list = MODULE_LIST_INIT;
 	int quiet = 0;
-	int i;
 
 	struct option module_init_options[] = {
 		OPT__QUIET(&quiet, N_("Suppress output for initializing a submodule")),
@@ -473,8 +489,11 @@ static int module_init(int argc, const char **argv, const char *prefix)
 	if (!argc && git_config_get_value_multi("submodule.active"))
 		module_list_active(&list);
 
-	for (i = 0; i < list.nr; i++)
-		init_submodule(list.entries[i]->name, prefix, quiet);
+	info.prefix = prefix;
+	info.quiet = !!quiet;
+
+	gitmodules_config();
+	for_each_submodule_list(list, init_submodule, &info);
 
 	return 0;
 }
-- 
2.13.0

[GSoC][PATCH 2/6 v2] submodule: port subcommand foreach from shell to C

[Prathamesh Chavan]

This aims to make git-submodule foreach a builtin. This is the very
first step taken in this direction. Hence, 'foreach' is ported to
submodule--helper, and submodule--helper is called from git-submodule.sh.
The code is split up to have one function to obtain all the list of
submodules. This function acts as the front-end of git-submodule foreach
subcommand. It calls the function for_each_submodule_list, which basically
loops through the list and calls function fn, which in this case is
runcommand_in_submodule. This third function is a calling function that
takes care of running the command in that submodule, and recursively
perform the same when --recursive is flagged.

The first function module_foreach first parses the options present in
argv, and then with the help of module_list_compute, generates the list of
submodules present in the current working tree.

The second function for_each_submodule_list traverses through the
list, and calls function fn (which in case of submodule subcommand
foreach is runcommand_in_submodule) is called for each entry.

The third function runcommand_in_submodule, generates a submodule struct sub
for $name, value and then later prepends name=sub->name; and other
value assignment to the env argv_array structure of a child_process.
Also the <command> of submodule-foreach is push to args argv_array
structure and finally, using run_command the commands are executed
using a shell.

The third function also takes care of the recursive flag, by creating
a separate child_process structure and prepending "--super-prefix displaypath",
to the args argv_array structure. Other required arguments and the
input <command> of submodule-foreach is also appended to this argv_array.

Function get_initial_wt_prefix_up_path is introduced to take care of
generating the value for path variable(as it was in the shell script)

Helped-by: Brandon Williams <bmwill@google.com>
Mentored-by: Christian Couder <christian.couder@gmail.com>
Mentored-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Prathamesh Chavan <pc44800@gmail.com>
---
This patch suggestes the current status of the foreach patch.
Work is still needed on this patch for eleminating the hack
used in this patch for generating path variable.

 builtin/submodule--helper.c | 163 ++++++++++++++++++++++++++++++++++++++++++++
 git-submodule.sh            |  39 +----------
 2 files changed, 164 insertions(+), 38 deletions(-)

diff --git a/builtin/submodule--helper.c b/builtin/submodule--helper.c
index c4286aac5..5180659fd 100644
--- a/builtin/submodule--helper.c
+++ b/builtin/submodule--helper.c
@@ -517,6 +517,168 @@ static int module_name(int argc, const char **argv, const char *prefix)
 	return 0;
 }
 
+static char *get_initial_wt_prefix_up_path(char *path)
+{
+	struct strbuf sb = STRBUF_INIT;
+	const char *p = path;
+
+	while (*p) {
+		if (skip_prefix(p, "./", &p))
+			continue;
+		if (!skip_prefix(p, "../", &p))
+			break;
+		strbuf_addstr(&sb, "../");
+	}
+
+	return strbuf_detach(&sb, NULL);
+}
+
+struct cb_foreach {
+	int argc;
+	const char **argv;
+	const char *prefix;
+	unsigned int quiet: 1;
+	unsigned int recursive: 1;
+};
+#define CB_FOREACH_INIT { 0, NULL, NULL, 0, 0 }
+
+static void runcommand_in_submodule(const struct cache_entry *list_item,
+				    void *cb_data)
+{
+	struct cb_foreach *info = cb_data;
+	const struct submodule *sub;
+	struct child_process cp = CHILD_PROCESS_INIT;
+	char *displaypath;
+
+	displaypath = get_submodule_displaypath(list_item->name, info->prefix);
+
+	sub = submodule_from_path(null_sha1, list_item->name);
+
+	if (!sub)
+		die(_("No url found for submodule path '%s' in .gitmodules"),
+		      displaypath);
+
+	if (!is_submodule_populated_gently(list_item->name, NULL))
+		goto cleanup;
+
+	prepare_submodule_repo_env(&cp.env_array);
+	/* For the purpose of executing <command> in the submodule,
+	 * separate shell is used for the purpose of running the
+	 * child process.
+	 */
+	cp.use_shell = 1;
+	cp.dir = list_item->name;
+
+	if (info->argc == 1) {
+
+		/*
+		 * NEEDSWORK: Here function get_initial_wt_prefix_up_path is
+		 * used as a hack for evaluating the value of the path
+		 * variable. The proper way would have been to store and use
+		 * the prefix of the repository, where first subcommand
+		 * foreach was executed and then evaluate path as
+		 * relative_path(list_item->name, prefix) for each submodule.
+		 */
+		char *initial_wt_prefix_up_path = get_initial_wt_prefix_up_path(displaypath);
+		char *toplevel = xgetcwd();
+		argv_array_pushf(&cp.env_array, "name=%s", sub->name);
+		argv_array_pushf(&cp.env_array, "sm_path=%s%s",
+				 initial_wt_prefix_up_path, list_item->name);
+		argv_array_pushf(&cp.env_array, "sha1=%s",
+				 oid_to_hex(&list_item->oid));
+		argv_array_pushf(&cp.env_array, "toplevel=%s", toplevel);
+
+		/*
+		 * NEEDSWORK: The value currently assigned to path variable
+		 * is same as that before porting, but it deviates
+		 * from its documented value: "$path is the name of the
+		 * submodule directory relative to the superproject", in
+		 * the case when subcommand foreach is called recursively
+		 * from a subdirectory.
+		 * This is beacuse it is currently relative path from cwd
+		 * to the submodule. In the nested case the intermediate
+		 * submodules are elided, such that it is a bogus path.
+		 */
+		argv_array_pushf(&cp.args, "path=%s%s; %s",
+				 initial_wt_prefix_up_path, list_item->name,
+				 info->argv[0]);
+		free(initial_wt_prefix_up_path);
+		free(toplevel);
+	} else {
+		argv_array_pushv(&cp.args, info->argv);
+	}
+
+	if (!info->quiet)
+		printf(_("Entering '%s'\n"), displaypath);
+
+	if (info->argv[0] && run_command(&cp))
+		die(_("run_command returned non-zero status for %s\n."),
+		      displaypath);
+
+	if (info->recursive) {
+		struct child_process cpr = CHILD_PROCESS_INIT;
+
+		cpr.git_cmd = 1;
+		cpr.dir = list_item->name;
+		prepare_submodule_repo_env(&cpr.env_array);
+
+		argv_array_pushl(&cpr.args, "--super-prefix", displaypath,
+				 "submodule--helper", "foreach", "--recursive",
+				 NULL);
+
+		if (info->quiet)
+			argv_array_push(&cpr.args, "--quiet");
+
+		argv_array_pushv(&cpr.args, info->argv);
+
+		if (run_command(&cpr))
+			die(_("run_command returned non-zero status while"
+			      "recursing in the nested submodules of %s\n."),
+			      displaypath);
+	}
+
+cleanup:
+	free(displaypath);
+}
+
+static int module_foreach(int argc, const char **argv, const char *prefix)
+{
+	struct cb_foreach info;
+	struct pathspec pathspec;
+	struct module_list list = MODULE_LIST_INIT;
+	int quiet = 0;
+	int recursive = 0;
+
+	struct option module_foreach_options[] = {
+		OPT__QUIET(&quiet, N_("Suppress output of entering each submodule command")),
+		OPT_BOOL(0, "recursive", &recursive,
+			 N_("Recurse into nested submodules")),
+		OPT_END()
+	};
+
+	const char *const git_submodule_helper_usage[] = {
+		N_("git submodule--helper foreach [--quiet] [--recursive] <command>"),
+		NULL
+	};
+
+	argc = parse_options(argc, argv, prefix, module_foreach_options,
+			     git_submodule_helper_usage, PARSE_OPT_KEEP_UNKNOWN);
+
+	if (module_list_compute(0, NULL, prefix, &pathspec, &list) < 0)
+		BUG("module_list_compute should not choke on empty pathspec");
+
+	info.argc = argc;
+	info.argv = argv;
+	info.prefix = prefix;
+	info.quiet = !!quiet;
+	info.recursive = !!recursive;
+
+	gitmodules_config();
+	for_each_submodule_list(list, runcommand_in_submodule, &info);
+
+	return 0;
+}
+
 static int clone_submodule(const char *path, const char *gitdir, const char *url,
 			   const char *depth, struct string_list *reference,
 			   int quiet, int progress)
@@ -1242,6 +1404,7 @@ static struct cmd_struct commands[] = {
 	{"relative-path", resolve_relative_path, 0},
 	{"resolve-relative-url", resolve_relative_url, 0},
 	{"resolve-relative-url-test", resolve_relative_url_test, 0},
+	{"foreach", module_foreach, SUPPORT_SUPER_PREFIX},
 	{"init", module_init, SUPPORT_SUPER_PREFIX},
 	{"remote-branch", resolve_remote_submodule_branch, 0},
 	{"push-check", push_check, 0},
diff --git a/git-submodule.sh b/git-submodule.sh
index e131760ee..c88e0ff7e 100755
--- a/git-submodule.sh
+++ b/git-submodule.sh
@@ -323,45 +323,8 @@ cmd_foreach()
 		shift
 	done
 
-	toplevel=$(pwd)
+	git ${wt_prefix:+-C "$wt_prefix"} ${prefix:+--super-prefix "$prefix"} submodule--helper foreach ${GIT_QUIET:+--quiet} ${recursive:+--recursive} "$@"
 
-	# dup stdin so that it can be restored when running the external
-	# command in the subshell (and a recursive call to this function)
-	exec 3<&0
-
-	{
-		git submodule--helper list --prefix "$wt_prefix" ||
-		echo "#unmatched" $?
-	} |
-	while read -r mode sha1 stage sm_path
-	do
-		die_if_unmatched "$mode" "$sha1"
-		if test -e "$sm_path"/.git
-		then
-			displaypath=$(git submodule--helper relative-path "$prefix$sm_path" "$wt_prefix")
-			say "$(eval_gettext "Entering '\$displaypath'")"
-			name=$(git submodule--helper name "$sm_path")
-			(
-				prefix="$prefix$sm_path/"
-				sanitize_submodule_env
-				cd "$sm_path" &&
-				sm_path=$(git submodule--helper relative-path "$sm_path" "$wt_prefix") &&
-				# we make $path available to scripts ...
-				path=$sm_path &&
-				if test $# -eq 1
-				then
-					eval "$1"
-				else
-					"$@"
-				fi &&
-				if test -n "$recursive"
-				then
-					cmd_foreach "--recursive" "$@"
-				fi
-			) <&3 3<&- ||
-			die "$(eval_gettext "Stopping at '\$displaypath'; script returned non-zero status.")"
-		fi
-	done
 }
 
 #
-- 
2.13.0

Re: [GSoC][PATCH 2/6 v2] submodule: port subcommand foreach from shell to C

[Christian Couder]

On Tue, Jun 27, 2017 at 1:11 AM, Prathamesh Chavan <pc44800@gmail.com> wrote:
> +
> +       if (!is_submodule_populated_gently(list_item->name, NULL))
> +               goto cleanup;
> +
> +       prepare_submodule_repo_env(&cp.env_array);
> +       /* For the purpose of executing <command> in the submodule,
> +        * separate shell is used for the purpose of running the
> +        * child process.
> +        */

As this comment spans over more than one line, it should be like:

/*
 * first line of comment
 * second line of comment
 * more stuff ...
 */

Also please explain WHY a shell is needed, we can see from the code
that we will use a shell.
So it should be something like:

/*
 * Use a shell because ...
 * and ...
 */

> +       cp.use_shell = 1;
> +       cp.dir = list_item->name;

[GSoC][PATCH 3/6 v2] submodule: port set_name_rev from shell to C

[Prathamesh Chavan]

Since later on we want to port submodule subcommand status, and since
set_name_rev is part of cmd_status, hence this function is ported. It
has been ported to function print_name_rev in C, which calls get_name_rev
to get the revname, and after formatting it, print_name_rev prints it.
And hence in this way, the command `git submodule--helper print-name-rev
"sm_path" "sha1"` sets value of revname in git-submodule.sh

The function get_name_rev returns the stdout of the git describe
commands. Since there are four different git-describe commands used for
generating the name rev, four child_process are introduced, each successive
child process running only when previous has no stdout. The order of these
four git-describe commands is maintained the same as it was in the function
set_name_rev() in shell script.

Mentored-by: Christian Couder <christian.couder@gmail.com>
Mentored-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Prathamesh Chavan <pc44800@gmail.com>
---
 builtin/submodule--helper.c | 69 +++++++++++++++++++++++++++++++++++++++++++++
 git-submodule.sh            | 16 ++---------
 2 files changed, 71 insertions(+), 14 deletions(-)

diff --git a/builtin/submodule--helper.c b/builtin/submodule--helper.c
index 5180659fd..86112ac92 100644
--- a/builtin/submodule--helper.c
+++ b/builtin/submodule--helper.c
@@ -244,6 +244,74 @@ static char *get_submodule_displaypath(const char *path, const char *prefix)
 	}
 }
 
+enum describe_step {
+	step_bare,
+	step_tags,
+	step_contains,
+	step_all_always,
+	step_end
+};
+
+static char *get_name_rev(const char *sub_path, const char* object_id)
+{
+	struct strbuf sb = STRBUF_INIT;
+	enum describe_step cur_step;
+
+	for (cur_step = step_bare; cur_step < step_end; cur_step++) {
+		struct child_process cp = CHILD_PROCESS_INIT;
+		prepare_submodule_repo_env(&cp.env_array);
+		cp.dir = sub_path;
+		cp.git_cmd = 1;
+		cp.no_stderr = 1;
+
+		switch (cur_step) {
+			case step_bare:
+				argv_array_pushl(&cp.args, "describe",
+						 object_id, NULL);
+				break;
+			case step_tags:	
+				argv_array_pushl(&cp.args, "describe",
+						 "--tags", object_id, NULL);
+				break;
+			case step_contains:
+				argv_array_pushl(&cp.args, "describe",
+						 "--contains", object_id,
+						 NULL);
+				break;
+			case step_all_always:
+				argv_array_pushl(&cp.args, "describe",
+						 "--all", "--always",
+						 object_id, NULL);
+				break;
+			default:
+				BUG("unknown describe step '%d'", cur_step);
+		}
+
+		if (!capture_command(&cp, &sb, 0) && sb.len) {
+			strbuf_strip_suffix(&sb, "\n");
+			return strbuf_detach(&sb, NULL);
+		}
+
+	}
+
+	strbuf_release(&sb);
+	return NULL;
+}
+
+static int print_name_rev(int argc, const char **argv, const char *prefix)
+{
+	char *namerev;
+	if (argc != 3)
+		die("print-name-rev only accepts two arguments: <path> <sha1>");
+
+	namerev = get_name_rev(argv[1], argv[2]);
+	if (namerev && namerev[0])
+		printf(" (%s)", namerev);
+	printf("\n");
+
+	return 0;
+}
+
 struct module_list {
 	const struct cache_entry **entries;
 	int alloc, nr;
@@ -1405,6 +1473,7 @@ static struct cmd_struct commands[] = {
 	{"resolve-relative-url", resolve_relative_url, 0},
 	{"resolve-relative-url-test", resolve_relative_url_test, 0},
 	{"foreach", module_foreach, SUPPORT_SUPER_PREFIX},
+	{"print-name-rev", print_name_rev, 0},
 	{"init", module_init, SUPPORT_SUPER_PREFIX},
 	{"remote-branch", resolve_remote_submodule_branch, 0},
 	{"push-check", push_check, 0},
diff --git a/git-submodule.sh b/git-submodule.sh
index c88e0ff7e..b28a6ba8e 100755
--- a/git-submodule.sh
+++ b/git-submodule.sh
@@ -722,18 +722,6 @@ cmd_update()
 	}
 }
 
-set_name_rev () {
-	revname=$( (
-		sanitize_submodule_env
-		cd "$1" && {
-			git describe "$2" 2>/dev/null ||
-			git describe --tags "$2" 2>/dev/null ||
-			git describe --contains "$2" 2>/dev/null ||
-			git describe --all --always "$2"
-		}
-	) )
-	test -z "$revname" || revname=" ($revname)"
-}
 #
 # Show commit summary for submodules in index or working tree
 #
@@ -1005,14 +993,14 @@ cmd_status()
 		fi
 		if git diff-files --ignore-submodules=dirty --quiet -- "$sm_path"
 		then
-			set_name_rev "$sm_path" "$sha1"
+			revname=$(git submodule--helper print-name-rev "$sm_path" "$sha1")
 			say " $sha1 $displaypath$revname"
 		else
 			if test -z "$cached"
 			then
 				sha1=$(sanitize_submodule_env; cd "$sm_path" && git rev-parse --verify HEAD)
 			fi
-			set_name_rev "$sm_path" "$sha1"
+			revname=$(git submodule--helper print-name-rev "$sm_path" "$sha1")
 			say "+$sha1 $displaypath$revname"
 		fi
 
-- 
2.13.0

[GSoC][PATCH 4/6 v2] submodule: port submodule subcommand status

[Prathamesh Chavan]

The mechanism used for porting submodule subcommand 'status'
is similar to that used for subcommand 'foreach'.
The function cmd_status from git-submodule is ported to three
functions in the builtin submodule--helper namely: module_status,
for_each_submodule_list and status_submodule.

print_status is also introduced for handling the output of
the subcommand and also to reduce the code size.

Mentored-by: Christian Couder <christian.couder@gmail.com>
Mentored-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Prathamesh Chavan <pc44800@gmail.com>
---
 builtin/submodule--helper.c | 152 ++++++++++++++++++++++++++++++++++++++++++++
 git-submodule.sh            |  49 +-------------
 2 files changed, 153 insertions(+), 48 deletions(-)

diff --git a/builtin/submodule--helper.c b/builtin/submodule--helper.c
index 86112ac92..a5de7a0fe 100644
--- a/builtin/submodule--helper.c
+++ b/builtin/submodule--helper.c
@@ -566,6 +566,157 @@ static int module_init(int argc, const char **argv, const char *prefix)
 	return 0;
 }
 
+struct status_cb {
+	const char *prefix;
+	unsigned int quiet: 1;
+	unsigned int recursive: 1;
+	unsigned int cached: 1;
+};
+#define STATUS_CB_INIT { NULL, 0, 0, 0 }
+
+static void print_status(struct status_cb *info, char state, const char *path,
+			 char *sub_sha1, char *displaypath)
+{
+	if (info->quiet)
+		return;
+
+	printf("%c%s %s", state, sub_sha1, displaypath);
+
+	if (state == ' ' || state == '+') {
+		struct argv_array name_rev_args = ARGV_ARRAY_INIT;
+
+		argv_array_pushl(&name_rev_args, "print-name-rev",
+				 path, sub_sha1, NULL);
+		print_name_rev(name_rev_args.argc, name_rev_args.argv,
+			       info->prefix);
+	} else {
+		printf("\n");
+	}
+}
+
+static void status_submodule(const struct cache_entry *list_item, void *cb_data)
+{
+	struct status_cb *info = cb_data;
+	char *sub_sha1 = xstrdup(oid_to_hex(&list_item->oid));
+	char *displaypath;
+	struct argv_array diff_files_args = ARGV_ARRAY_INIT;
+
+	if (!submodule_from_path(null_sha1, list_item->name))
+		die(_("no submodule mapping found in .gitmodules for path '%s'"),
+		      list_item->name);
+
+	displaypath = get_submodule_displaypath(list_item->name, info->prefix);
+
+	if (list_item->ce_flags) {
+		print_status(info, 'U', list_item->name,
+			     sha1_to_hex(null_sha1), displaypath);
+		goto cleanup;
+	}
+
+	if (!is_submodule_initialized(list_item->name)) {
+		print_status(info, '-', list_item->name, sub_sha1, displaypath);
+		goto cleanup;
+	}
+
+	argv_array_pushl(&diff_files_args, "diff-files",
+			 "--ignore-submodules=dirty", "--quiet", "--",
+			 list_item->name, NULL);
+
+	if (!cmd_diff_files(diff_files_args.argc, diff_files_args.argv,
+			    info->prefix)) {
+		print_status(info, ' ', list_item->name, sub_sha1, displaypath);
+	} else {
+		if (!info->cached) {
+			struct child_process cp = CHILD_PROCESS_INIT;
+			struct strbuf sb = STRBUF_INIT;
+
+			prepare_submodule_repo_env(&cp.env_array);
+			cp.git_cmd = 1;
+			cp.dir = list_item->name;
+
+			argv_array_pushl(&cp.args, "rev-parse",
+					 "--verify", "HEAD", NULL);
+
+			if (capture_command(&cp, &sb, 0))
+				die(_("could not run 'git rev-parse --verify"
+				      "HEAD' in submodule %s"),
+				      list_item->name);
+
+			strbuf_strip_suffix(&sb, "\n");
+			print_status(info, '+', list_item->name, sb.buf,
+				     displaypath);
+			strbuf_release(&sb);
+		} else {
+			print_status(info, '+', list_item->name, sub_sha1,
+				     displaypath);
+		}
+	}
+
+	if (info->recursive) {
+		struct child_process cpr = CHILD_PROCESS_INIT;
+
+		cpr.git_cmd = 1;
+		cpr.dir = list_item->name;
+		prepare_submodule_repo_env(&cpr.env_array);
+
+		argv_array_pushl(&cpr.args, "--super-prefix", displaypath,
+				 "submodule--helper", "status", "--recursive",
+				 NULL);
+
+		if (info->cached)
+			argv_array_push(&cpr.args, "--cached");
+
+		if (info->quiet)
+			argv_array_push(&cpr.args, "--quiet");
+
+		if (run_command(&cpr))
+			die(_("failed to recurse into submodule '%s'"),
+			      list_item->name);
+	}
+
+cleanup:
+	free(displaypath);
+	free(sub_sha1);
+}
+
+static int module_status(int argc, const char **argv, const char *prefix)
+{
+	struct status_cb info = STATUS_CB_INIT;
+	struct pathspec pathspec;
+	struct module_list list = MODULE_LIST_INIT;
+	int quiet = 0;
+	int cached = 0;
+	int recursive = 0;
+
+	struct option module_status_options[] = {
+		OPT__QUIET(&quiet, N_("Suppress submodule status output")),
+		OPT_BOOL(0, "cached", &cached, N_("Use commit stored in the index instead of the one stored in the submodule HEAD")),
+		OPT_BOOL(0, "recursive", &recursive, N_("Recurse into nested submodules")),
+		OPT_END()
+	};
+
+	const char *const git_submodule_helper_usage[] = {
+		N_("git submodule status [--quiet] [--cached] [--recursive] [<path>]"),
+		NULL
+	};
+
+	argc = parse_options(argc, argv, prefix, module_status_options,
+			     git_submodule_helper_usage, 0);
+
+	if (module_list_compute(argc, argv, prefix, &pathspec, &list) < 0)
+		return 1;
+
+	info.prefix = prefix;
+	info.quiet = !!quiet;
+	info.recursive = !!recursive;
+	info.cached = !!cached;
+
+	gitmodules_config();
+	for_each_submodule_list(list, status_submodule, &info);
+
+	return 0;
+}
+
 static int module_name(int argc, const char **argv, const char *prefix)
 {
 	const struct submodule *sub;
@@ -1475,6 +1626,7 @@ static struct cmd_struct commands[] = {
 	{"foreach", module_foreach, SUPPORT_SUPER_PREFIX},
 	{"print-name-rev", print_name_rev, 0},
 	{"init", module_init, SUPPORT_SUPER_PREFIX},
+	{"status", module_status, SUPPORT_SUPER_PREFIX},
 	{"remote-branch", resolve_remote_submodule_branch, 0},
 	{"push-check", push_check, 0},
 	{"absorb-git-dirs", absorb_git_dirs, SUPPORT_SUPER_PREFIX},
diff --git a/git-submodule.sh b/git-submodule.sh
index b28a6ba8e..b19d5fa7b 100755
--- a/git-submodule.sh
+++ b/git-submodule.sh
@@ -968,54 +968,7 @@ cmd_status()
 		shift
 	done
 
-	{
-		git submodule--helper list --prefix "$wt_prefix" "$@" ||
-		echo "#unmatched" $?
-	} |
-	while read -r mode sha1 stage sm_path
-	do
-		die_if_unmatched "$mode" "$sha1"
-		name=$(git submodule--helper name "$sm_path") || exit
-		displaypath=$(git submodule--helper relative-path "$prefix$sm_path" "$wt_prefix")
-		if test "$stage" = U
-		then
-			say "U$sha1 $displaypath"
-			continue
-		fi
-		if ! git submodule--helper is-active "$sm_path" ||
-		{
-			! test -d "$sm_path"/.git &&
-			! test -f "$sm_path"/.git
-		}
-		then
-			say "-$sha1 $displaypath"
-			continue;
-		fi
-		if git diff-files --ignore-submodules=dirty --quiet -- "$sm_path"
-		then
-			revname=$(git submodule--helper print-name-rev "$sm_path" "$sha1")
-			say " $sha1 $displaypath$revname"
-		else
-			if test -z "$cached"
-			then
-				sha1=$(sanitize_submodule_env; cd "$sm_path" && git rev-parse --verify HEAD)
-			fi
-			revname=$(git submodule--helper print-name-rev "$sm_path" "$sha1")
-			say "+$sha1 $displaypath$revname"
-		fi
-
-		if test -n "$recursive"
-		then
-			(
-				prefix="$displaypath/"
-				sanitize_submodule_env
-				wt_prefix=
-				cd "$sm_path" &&
-				eval cmd_status
-			) ||
-			die "$(eval_gettext "Failed to recurse into submodule path '\$sm_path'")"
-		fi
-	done
+	git ${wt_prefix:+-C "$wt_prefix"} ${prefix:+--super-prefix "$prefix"} submodule--helper status ${GIT_QUIET:+--quiet} ${cached:+--cached} ${recursive:+--recursive} "$@"
 }
 #
 # Sync remote urls for submodules
-- 
2.13.0

[GSoC][PATCH 5/6 v2] submodule: port submodule subcommand sync from shell to C

[Prathamesh Chavan]

The mechanism used for porting the submodule subcommand 'sync' is
similar to that of 'foreach', where we split the function cmd_sync
from shell into three functions in C, module_sync,
for_each_submodule_list and sync_submodule.

print_default_remote is introduced as a submodule--helper
subcommand for getting the default remote as stdout.

Mentored-by: Christian Couder <christian.couder@gmail.com>
Mentored-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Prathamesh Chavan <pc44800@gmail.com>
---
 builtin/submodule--helper.c | 178 ++++++++++++++++++++++++++++++++++++++++++++
 git-submodule.sh            |  56 +-------------
 2 files changed, 179 insertions(+), 55 deletions(-)

diff --git a/builtin/submodule--helper.c b/builtin/submodule--helper.c
index a5de7a0fe..4e3322846 100644
--- a/builtin/submodule--helper.c
+++ b/builtin/submodule--helper.c
@@ -44,6 +44,20 @@ static char *get_default_remote(void)
 	return ret;
 }
 
+static int print_default_remote(int argc, const char **argv, const char *prefix)
+{
+	const char *remote;
+
+	if (argc != 1)
+		die(_("submodule--helper print-default-remote takes no arguments"));
+
+	remote = get_default_remote();
+	if (remote)
+		puts(remote);
+
+	return 0;
+}
+
 static int starts_with_dot_slash(const char *str)
 {
 	return str[0] == '.' && is_dir_sep(str[1]);
@@ -385,6 +399,26 @@ static void module_list_active(struct module_list *list)
 	*list = active_modules;
 }
 
+static char *get_up_path(const char *path)
+{
+	int i = count_slashes(path);
+	int l = strlen(path);
+	struct strbuf sb = STRBUF_INIT;
+
+	while (i--)
+		strbuf_addstr(&sb, "../");
+
+	/*
+	 *Check if 'path' ends with slash or not
+	 *for having the same output for dir/sub_dir
+	 *and dir/sub_dir/
+	 */
+	if (!is_dir_sep(path[l - 1]))
+		strbuf_addstr(&sb, "../");
+
+	return strbuf_detach(&sb, NULL);
+}
+
 static int module_list(int argc, const char **argv, const char *prefix)
 {
 	int i;
@@ -898,6 +932,148 @@ static int module_foreach(int argc, const char **argv, const char *prefix)
 	return 0;
 }
 
+struct sync_cb {
+	const char *prefix;
+	unsigned int quiet: 1;
+	unsigned int recursive: 1;
+};
+#define SYNC_CB_INIT { NULL, 0, 0 }
+
+static void sync_submodule(const struct cache_entry *list_item, void *cb_data)
+{
+	struct sync_cb *info = cb_data;
+	const struct submodule *sub;
+	char *sub_key, *remote_key;
+	char *sub_origin_url, *super_config_url, *displaypath;
+	struct strbuf sb = STRBUF_INIT;
+	struct child_process cp = CHILD_PROCESS_INIT;
+
+	if (!is_submodule_initialized(list_item->name))
+		return;
+
+	sub = submodule_from_path(null_sha1, list_item->name);
+
+	if (!sub && !sub->url)
+		die(_("no url found for submodule path '%s' in .gitmodules"),
+		      list_item->name);
+
+	if (starts_with_dot_dot_slash(sub->url) || starts_with_dot_slash(sub->url)) {
+		char *remote_url, *up_path;
+		char *remote = get_default_remote();
+		char *remote_key = xstrfmt("remote.%s.url", remote);
+		free(remote);
+
+		if (git_config_get_string(remote_key, &remote_url))
+			remote_url = xgetcwd();
+		up_path = get_up_path(list_item->name);
+		sub_origin_url = relative_url(remote_url, sub->url, up_path);
+		super_config_url = relative_url(remote_url, sub->url, NULL);
+		free(remote_key);
+		free(up_path);
+		free(remote_url);
+	} else {
+		sub_origin_url = xstrdup(sub->url);
+		super_config_url = xstrdup(sub->url);
+	}
+
+	displaypath = get_submodule_displaypath(list_item->name, info->prefix);
+
+	if (!info->quiet)
+		printf(_("Synchronizing submodule url for '%s'\n"),
+			 displaypath);
+
+	sub_key = xstrfmt("submodule.%s.url", sub->name);
+	if (git_config_set_gently(sub_key, super_config_url))
+		die(_("failed to register url for submodule path '%s'"),
+		      displaypath);
+
+	if (!is_submodule_populated_gently(list_item->name, NULL))
+		goto cleanup;
+
+	prepare_submodule_repo_env(&cp.env_array);
+	cp.git_cmd = 1;
+	cp.dir = list_item->name;
+	argv_array_pushl(&cp.args, "submodule--helper",
+			 "print-default-remote", NULL);
+	if (capture_command(&cp, &sb, 0))
+		die(_("failed to get the default remote for submodule '%s'"),
+		      list_item->name);
+
+	strbuf_strip_suffix(&sb, "\n");
+	remote_key = xstrfmt("remote.%s.url", sb.buf);
+	strbuf_release(&sb);
+
+	child_process_init(&cp);
+	prepare_submodule_repo_env(&cp.env_array);
+	cp.git_cmd = 1;
+	cp.dir = list_item->name;
+	argv_array_pushl(&cp.args, "config", remote_key, sub_origin_url, NULL);
+	if (run_command(&cp))
+		die(_("failed to update remote for submodule '%s'"),
+		      list_item->name);
+
+	if (info->recursive) {
+		struct child_process cpr = CHILD_PROCESS_INIT;
+
+		cpr.git_cmd = 1;
+		cpr.dir = list_item->name;
+		prepare_submodule_repo_env(&cpr.env_array);
+
+		argv_array_pushl(&cpr.args, "--super-prefix", displaypath,
+				 "submodule--helper", "sync", "--recursive",
+				 NULL);
+
+		if (info->quiet)
+			argv_array_push(&cpr.args, "--quiet");
+
+		if (run_command(&cpr))
+			die(_("failed to recurse into submodule '%s'"),
+			      list_item->name);
+	}
+
+cleanup:
+	free(sub_key);
+	free(super_config_url);
+	free(displaypath);
+	free(sub_origin_url);
+}
+
+static int module_sync(int argc, const char **argv, const char *prefix)
+{
+	struct sync_cb info = SYNC_CB_INIT;
+	struct pathspec pathspec;
+	struct module_list list = MODULE_LIST_INIT;
+	int quiet = 0;
+	int recursive = 0;
+
+	struct option module_sync_options[] = {
+		OPT__QUIET(&quiet, N_("Suppress output of synchronizing submodule url")),
+		OPT_BOOL(0, "recursive", &recursive,
+			N_("Recurse into nested submodules")),
+		OPT_END()
+	};
+
+	const char *const git_submodule_helper_usage[] = {
+		N_("git submodule--helper sync [--quiet] [--recursive] [<path>]"),
+		NULL
+	};
+
+	argc = parse_options(argc, argv, prefix, module_sync_options,
+			     git_submodule_helper_usage, 0);
+
+	if (module_list_compute(argc, argv, prefix, &pathspec, &list) < 0)
+		return 1;
+
+	info.prefix = prefix;
+	info.quiet = !!quiet;
+	info.recursive = !!recursive;
+
+	gitmodules_config();
+	for_each_submodule_list(list, sync_submodule, &info);
+
+	return 0;
+}
+
 static int clone_submodule(const char *path, const char *gitdir, const char *url,
 			   const char *depth, struct string_list *reference,
 			   int quiet, int progress)
@@ -1627,6 +1803,8 @@ static struct cmd_struct commands[] = {
 	{"print-name-rev", print_name_rev, 0},
 	{"init", module_init, SUPPORT_SUPER_PREFIX},
 	{"status", module_status, SUPPORT_SUPER_PREFIX},
+	{"print-default-remote", print_default_remote, 0},
+	{"sync", module_sync, SUPPORT_SUPER_PREFIX},
 	{"remote-branch", resolve_remote_submodule_branch, 0},
 	{"push-check", push_check, 0},
 	{"absorb-git-dirs", absorb_git_dirs, SUPPORT_SUPER_PREFIX},
diff --git a/git-submodule.sh b/git-submodule.sh
index b19d5fa7b..6257d50e9 100755
--- a/git-submodule.sh
+++ b/git-submodule.sh
@@ -1000,63 +1000,9 @@ cmd_sync()
 			;;
 		esac
 	done
-	cd_to_toplevel
-	{
-		git submodule--helper list --prefix "$wt_prefix" "$@" ||
-		echo "#unmatched" $?
-	} |
-	while read -r mode sha1 stage sm_path
-	do
-		die_if_unmatched "$mode" "$sha1"
-
-		# skip inactive submodules
-		if ! git submodule--helper is-active "$sm_path"
-		then
-			continue
-		fi
-
-		name=$(git submodule--helper name "$sm_path")
-		url=$(git config -f .gitmodules --get submodule."$name".url)
-
-		# Possibly a url relative to parent
-		case "$url" in
-		./*|../*)
-			# rewrite foo/bar as ../.. to find path from
-			# submodule work tree to superproject work tree
-			up_path="$(printf '%s\n' "$sm_path" | sed "s/[^/][^/]*/../g")" &&
-			# guarantee a trailing /
-			up_path=${up_path%/}/ &&
-			# path from submodule work tree to submodule origin repo
-			sub_origin_url=$(git submodule--helper resolve-relative-url "$url" "$up_path") &&
-			# path from superproject work tree to submodule origin repo
-			super_config_url=$(git submodule--helper resolve-relative-url "$url") || exit
-			;;
-		*)
-			sub_origin_url="$url"
-			super_config_url="$url"
-			;;
-		esac
 
-		displaypath=$(git submodule--helper relative-path "$prefix$sm_path" "$wt_prefix")
-		say "$(eval_gettext "Synchronizing submodule url for '\$displaypath'")"
-		git config submodule."$name".url "$super_config_url"
+	git ${wt_prefix:+-C "$wt_prefix"} ${prefix:+--super-prefix "$prefix"} submodule--helper sync ${GIT_QUIET:+--quiet} ${recursive:+--recursive} "$@"
 
-		if test -e "$sm_path"/.git
-		then
-		(
-			sanitize_submodule_env
-			cd "$sm_path"
-			remote=$(get_default_remote)
-			git config remote."$remote".url "$sub_origin_url"
-
-			if test -n "$recursive"
-			then
-				prefix="$prefix$sm_path/"
-				eval cmd_sync
-			fi
-		)
-		fi
-	done
 }
 
 cmd_absorbgitdirs()
-- 
2.13.0

Re: [GSoC][PATCH 5/6 v2] submodule: port submodule subcommand sync from shell to C

[Christian Couder]

On Tue, Jun 27, 2017 at 1:11 AM, Prathamesh Chavan <pc44800@gmail.com> wrote:

> +static char *get_up_path(const char *path)
> +{
> +       int i = count_slashes(path);
> +       int l = strlen(path);

Nit: "l" is quite similar to "i" in many fonts, so maybe use "len"
instead of "l", but see below.

> +       struct strbuf sb = STRBUF_INIT;
> +
> +       while (i--)
> +               strbuf_addstr(&sb, "../");

Nit: a regular "for" loop like the following might be easier to review:

for (i = count_slashes(path); i; i--)
        strbuf_addstr(&sb, "../");

> +       /*
> +        *Check if 'path' ends with slash or not
> +        *for having the same output for dir/sub_dir
> +        *and dir/sub_dir/
> +        */
> +       if (!is_dir_sep(path[l - 1]))

As "l" is used only here, maybe we could get rid of this variable
altogether with something like:

      if (!is_dir_sep(path[strlen(path) - 1]))

> +               strbuf_addstr(&sb, "../");
> +
> +       return strbuf_detach(&sb, NULL);
> +}

> +static void sync_submodule(const struct cache_entry *list_item, void *cb_data)
> +{
> +       struct sync_cb *info = cb_data;
> +       const struct submodule *sub;
> +       char *sub_key, *remote_key;
> +       char *sub_origin_url, *super_config_url, *displaypath;
> +       struct strbuf sb = STRBUF_INIT;
> +       struct child_process cp = CHILD_PROCESS_INIT;
> +
> +       if (!is_submodule_initialized(list_item->name))
> +               return;
> +
> +       sub = submodule_from_path(null_sha1, list_item->name);
> +
> +       if (!sub && !sub->url)

I think it should be "(!sub || !sub->url)".

> +               die(_("no url found for submodule path '%s' in .gitmodules"),
> +                     list_item->name);

[GSoC][PATCH 6/6 v2] submodule: port submodule subcommand 'deinit' from shell to C

[Prathamesh Chavan]

The same mechanism is used even for porting this submodule
subcommand, as used in the ported subcommands till now.
The function cmd_deinit in split up after porting into three
functions: module_deinit, for_each_submodule_list and
deinit_submodule.

Mentored-by: Christian Couder <christian.couder@gmail.com>
Mentored-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Prathamesh Chavan <pc44800@gmail.com>
---
 builtin/submodule--helper.c | 140 ++++++++++++++++++++++++++++++++++++++++++++
 git-submodule.sh            |  55 +----------------
 2 files changed, 141 insertions(+), 54 deletions(-)

diff --git a/builtin/submodule--helper.c b/builtin/submodule--helper.c
index 4e3322846..17942529b 100644
--- a/builtin/submodule--helper.c
+++ b/builtin/submodule--helper.c
@@ -751,6 +751,145 @@ static int module_status(int argc, const char **argv, const char *prefix)
 	return 0;
 }
 
+struct deinit_cb {
+	const char *prefix;
+	unsigned int quiet: 1;
+	unsigned int force: 1;
+	unsigned int all: 1;
+};
+#define DEINIT_CB_INIT { NULL, 0, 0, 0 }
+
+static void deinit_submodule(const struct cache_entry *list_item,
+			     void *cb_data)
+{
+	struct deinit_cb *info = cb_data;
+	const struct submodule *sub;
+	char *displaypath = NULL;
+	struct child_process cp_config = CHILD_PROCESS_INIT;
+	struct strbuf sb_config = STRBUF_INIT;
+	char *sm_path = xstrdup(list_item->name);
+	char *sub_git_dir = xstrfmt("%s/.git", sm_path);
+
+	sub = submodule_from_path(null_sha1, sm_path);
+
+	if (!sub->name)
+		goto cleanup;
+
+	displaypath = get_submodule_displaypath(sm_path, info->prefix);
+
+	/* remove the submodule work tree (unless the user already did it) */
+	if (is_directory(sm_path)) {
+		struct child_process cp = CHILD_PROCESS_INIT;
+
+		/* protect submodules containing a .git directory */
+		if (is_git_directory(sub_git_dir))
+			die(_("Submodule work tree '%s' contains a .git "
+			      "directory use 'rm -rf' if you really want "
+			      "to remove it including all of its history"),
+			      displaypath);
+
+		if (!info->force) {
+			struct child_process cp_rm = CHILD_PROCESS_INIT;
+			cp_rm.git_cmd = 1;
+			argv_array_pushl(&cp_rm.args, "rm", "-qn", sm_path,
+					 NULL);
+
+			/* list_item->name is changed by cmd_rm() below */
+			if (run_command(&cp_rm))
+				die(_("Submodule work tree '%s' contains local "
+				      "modifications; use '-f' to discard them"),
+				      displaypath);
+		}
+
+		cp.use_shell = 1;
+		argv_array_pushl(&cp.args, "rm", "-rf", sm_path, NULL);
+		if (!run_command(&cp)) {
+			if (!info->quiet)
+				printf(_("Cleared directory '%s'\n"),
+					 displaypath);
+		} else {
+			if (!info->quiet)
+				printf(_("Could not remove submodule work tree '%s'\n"),
+					 displaypath);
+		}
+	}
+
+	if (mkdir(sm_path, 0700))
+		die(_("could not create empty submodule directory %s"),
+		      displaypath);
+
+	cp_config.git_cmd = 1;
+	argv_array_pushl(&cp_config.args, "config", "--get-regexp", NULL);
+	argv_array_pushf(&cp_config.args, "submodule.%s\\.", sub->name);
+
+	/* remove the .git/config entries (unless the user already did it) */
+	if (!capture_command(&cp_config, &sb_config, 0) && sb_config.len) {
+		char *sub_key = xstrfmt("submodule.%s", sub->name);
+		/*
+		 * remove the whole section so we have a clean state when
+		 * the user later decides to init this submodule again
+		 */
+		git_config_rename_section_in_file(NULL, sub_key, NULL);
+		if (!info->quiet)
+			printf(_("Submodule '%s' (%s) unregistered for path '%s'\n"),
+				 sub->name, sub->url, displaypath);
+		free(sub_key);
+	}
+
+cleanup:
+	free(displaypath);
+	free(sub_git_dir);
+	free(sm_path);
+	strbuf_release(&sb_config);
+}
+
+static int module_deinit(int argc, const char **argv, const char *prefix)
+{
+	struct deinit_cb info = DEINIT_CB_INIT;
+	struct pathspec pathspec;
+	struct module_list list = MODULE_LIST_INIT;
+	int quiet = 0;
+	int force = 0;
+	int all = 0;
+
+	struct option module_deinit_options[] = {
+		OPT__QUIET(&quiet, N_("Suppress submodule status output")),
+		OPT__FORCE(&force, N_("Remove submodule working trees even if they contain local changes")),
+		OPT_BOOL(0, "all", &all, N_("Unregister all submodules")),
+		OPT_END()
+	};
+
+	const char *const git_submodule_helper_usage[] = {
+		N_("git submodule deinit [--quiet] [-f | --force] [--all | [--] [<path>...]]"),
+		NULL
+	};
+
+	argc = parse_options(argc, argv, prefix, module_deinit_options,
+			     git_submodule_helper_usage, 0);
+
+	if (module_list_compute(argc, argv, prefix, &pathspec, &list) < 0)
+		BUG("module_list_compute should not choke on empty pathspec");
+
+	info.prefix = prefix;
+	info.quiet = !!quiet;
+	info.all = !!all;
+	info.force = !!force;
+
+	if (all && argc) {
+		error("pathspec and --all are incompatible");
+		usage_with_options(git_submodule_helper_usage,
+				   module_deinit_options);
+	}
+
+	if (!argc && !all)
+		die(_("Use '--all' if you really want to deinitialize all submodules"));
+
+	gitmodules_config();
+	for_each_submodule_list(list, deinit_submodule, &info);
+
+	return 0;
+}
+
 static int module_name(int argc, const char **argv, const char *prefix)
 {
 	const struct submodule *sub;
@@ -1805,6 +1944,7 @@ static struct cmd_struct commands[] = {
 	{"status", module_status, SUPPORT_SUPER_PREFIX},
 	{"print-default-remote", print_default_remote, 0},
 	{"sync", module_sync, SUPPORT_SUPER_PREFIX},
+	{"deinit", module_deinit, SUPPORT_SUPER_PREFIX},
 	{"remote-branch", resolve_remote_submodule_branch, 0},
 	{"push-check", push_check, 0},
 	{"absorb-git-dirs", absorb_git_dirs, SUPPORT_SUPER_PREFIX},
diff --git a/git-submodule.sh b/git-submodule.sh
index 6257d50e9..0d3308d7b 100755
--- a/git-submodule.sh
+++ b/git-submodule.sh
@@ -391,60 +391,7 @@ cmd_deinit()
 		shift
 	done
 
-	if test -n "$deinit_all" && test "$#" -ne 0
-	then
-		echo >&2 "$(eval_gettext "pathspec and --all are incompatible")"
-		usage
-	fi
-	if test $# = 0 && test -z "$deinit_all"
-	then
-		die "$(eval_gettext "Use '--all' if you really want to deinitialize all submodules")"
-	fi
-
-	{
-		git submodule--helper list --prefix "$wt_prefix" "$@" ||
-		echo "#unmatched" $?
-	} |
-	while read -r mode sha1 stage sm_path
-	do
-		die_if_unmatched "$mode" "$sha1"
-		name=$(git submodule--helper name "$sm_path") || exit
-
-		displaypath=$(git submodule--helper relative-path "$sm_path" "$wt_prefix")
-
-		# Remove the submodule work tree (unless the user already did it)
-		if test -d "$sm_path"
-		then
-			# Protect submodules containing a .git directory
-			if test -d "$sm_path/.git"
-			then
-				die "$(eval_gettext "\
-Submodule work tree '\$displaypath' contains a .git directory
-(use 'rm -rf' if you really want to remove it including all of its history)")"
-			fi
-
-			if test -z "$force"
-			then
-				git rm -qn "$sm_path" ||
-				die "$(eval_gettext "Submodule work tree '\$displaypath' contains local modifications; use '-f' to discard them")"
-			fi
-			rm -rf "$sm_path" &&
-			say "$(eval_gettext "Cleared directory '\$displaypath'")" ||
-			say "$(eval_gettext "Could not remove submodule work tree '\$displaypath'")"
-		fi
-
-		mkdir "$sm_path" || say "$(eval_gettext "Could not create empty submodule directory '\$displaypath'")"
-
-		# Remove the .git/config entries (unless the user already did it)
-		if test -n "$(git config --get-regexp submodule."$name\.")"
-		then
-			# Remove the whole section so we have a clean state when
-			# the user later decides to init this submodule again
-			url=$(git config submodule."$name".url)
-			git config --remove-section submodule."$name" 2>/dev/null &&
-			say "$(eval_gettext "Submodule '\$name' (\$url) unregistered for path '\$displaypath'")"
-		fi
-	done
+	git ${wt_prefix:+-C "$wt_prefix"} submodule--helper deinit ${GIT_QUIET:+--quiet} ${prefix:+--prefix "$prefix"} ${force:+--force} ${deinit_all:+--all} "$@"
 }
 
 is_tip_reachable () (
-- 
2.13.0

Re: [GSoC][PATCH 6/6 v2] submodule: port submodule subcommand 'deinit' from shell to C

[Christian Couder]

On Tue, Jun 27, 2017 at 1:11 AM, Prathamesh Chavan <pc44800@gmail.com> wrote:

> +static void deinit_submodule(const struct cache_entry *list_item,
> +                            void *cb_data)
> +{
> +       struct deinit_cb *info = cb_data;
> +       const struct submodule *sub;
> +       char *displaypath = NULL;
> +       struct child_process cp_config = CHILD_PROCESS_INIT;
> +       struct strbuf sb_config = STRBUF_INIT;
> +       char *sm_path = xstrdup(list_item->name);
> +       char *sub_git_dir = xstrfmt("%s/.git", sm_path);
> +
> +       sub = submodule_from_path(null_sha1, sm_path);
> +
> +       if (!sub->name)

In the previous patch "!sub" is used before "!sub->url", so we might
want to check "!sub" here too.

> +               goto cleanup;
> +
> +       displaypath = get_submodule_displaypath(sm_path, info->prefix);
> +
> +       /* remove the submodule work tree (unless the user already did it) */
> +       if (is_directory(sm_path)) {
> +               struct child_process cp = CHILD_PROCESS_INIT;
> +
> +               /* protect submodules containing a .git directory */
> +               if (is_git_directory(sub_git_dir))
> +                       die(_("Submodule work tree '%s' contains a .git "
> +                             "directory use 'rm -rf' if you really want "
> +                             "to remove it including all of its history"),
> +                             displaypath);
> +
> +               if (!info->force) {
> +                       struct child_process cp_rm = CHILD_PROCESS_INIT;
> +                       cp_rm.git_cmd = 1;
> +                       argv_array_pushl(&cp_rm.args, "rm", "-qn", sm_path,
> +                                        NULL);
> +
> +                       /* list_item->name is changed by cmd_rm() below */

It looks like cmd_rm() is not used anymore below, so this comment
could go and the sm_path variable might not be needed any more.

> +                       if (run_command(&cp_rm))
> +                               die(_("Submodule work tree '%s' contains local "
> +                                     "modifications; use '-f' to discard them"),
> +                                     displaypath);
> +               }
> +
> +               cp.use_shell = 1;

Do we really need a shell here?

> +               argv_array_pushl(&cp.args, "rm", "-rf", sm_path, NULL);
> +               if (!run_command(&cp)) {
> +                       if (!info->quiet)
> +                               printf(_("Cleared directory '%s'\n"),
> +                                        displaypath);
> +               } else {
> +                       if (!info->quiet)
> +                               printf(_("Could not remove submodule work tree '%s'\n"),
> +                                        displaypath);
> +               }
> +       }
> +
> +       if (mkdir(sm_path, 0700))

Are you sure about the 0700 mode?
Shouldn't this depend on the shared repository settings?

> +               die(_("could not create empty submodule directory %s"),
> +                     displaypath);

Re: [GSoC][PATCH 1/6 v2] submodule--helper: introduce for_each_submodule_list

[Junio C Hamano]

Prathamesh Chavan <pc44800@gmail.com> writes:

> Introduce function for_each_submodule_list for using it
> in the later patches, related to porting submodule
> subcommands from shell to C.
> This new function is also used in ported submodule subcommand
> init.

The patch text looks sensible.  It would be easier for "git log"
readers to understand, if the change is explained like so:

	Introduce function for_each_submodule_list() and
	replace a loop in module_init() with a call to it.

	The new function will also be used in other parts of the
	system in later patches.

That way, readers do not have to judge the merit of this change
based on a vague promise "it will help world better with future
patches", but can instead judge on its immediate benefit that it
refactors a useful bit out of an existing code.

> Mentored-by: Christian Couder <christian.couder@gmail.com>
> Mentored-by: Stefan Beller <sbeller@google.com>
> Signed-off-by: Prathamesh Chavan <pc44800@gmail.com>
> ---
> This series of patches is based on the 'next' branch. 

The reason not to base on 'master' is...?

The thing is that a topic built on 'next' cannot be merged down to
'master' until _all_ other topics in 'next' graduate to 'master',
which may never happen.  If you are depending on one or more topics,
please make sure to name them.  Then we can

 (1) create a branch from the tip of 'master';
 (2) merge these topics you depend on into that branch; and then
 (3) apply these patches.

The topic still needs to wait until these other topis graduate, but
at least you would not be blocked by unrelated topics that way.

You _might_ be building on 'next' because you want to make sure that
your topic works not just with master but also want to make sure
that there won't be any unexpected breakage when used with topics in
'next', even though your topic does not depend on anything in 'next'
in particular.  It is a good development discipline to pay attention
to other topics in flight and I applaud you for it if that is why
you based it on 'next'.  But the right way to do it would be to
build your topic on 'master', and then in addition to testing the
topic by itself, also make a trial merge of your topic into 'next'
and test the result as well.

Thanks.

Re: [GSoC][PATCH 1/6 v2] submodule--helper: introduce for_each_submodule_list

[Prathamesh Chavan]

>> This series of patches is based on the 'next' branch.
>
> The reason not to base on 'master' is...?
>

The reason it wasn't based on 'master' was that it depended on the commit:
dir: create function count_slashes(),
which was merged to 'next' a few days back.

> The thing is that a topic built on 'next' cannot be merged down to
> 'master' until _all_ other topics in 'next' graduate to 'master',
> which may never happen.  If you are depending on one or more topics,
> please make sure to name them.  Then we can
>
>  (1) create a branch from the tip of 'master';
>  (2) merge these topics you depend on into that branch; and then
>  (3) apply these patches.
>
I'll soon be updating this patch series and will create the new patch series in
accordance with the above routine.

> The topic still needs to wait until these other topis graduate, but
> at least you would not be blocked by unrelated topics that way.
>
> You _might_ be building on 'next' because you want to make sure that
> your topic works not just with master but also want to make sure
> that there won't be any unexpected breakage when used with topics in
> 'next', even though your topic does not depend on anything in 'next'
> in particular.  It is a good development discipline to pay attention
> to other topics in flight and I applaud you for it if that is why
> you based it on 'next'.  But the right way to do it would be to
> build your topic on 'master', and then in addition to testing the
> topic by itself, also make a trial merge of your topic into 'next'
> and test the result as well.
>
Thanks for making me aware about this as well. And will be following this
before sending out the updated patch-series.

Thanks,
Prathamesh Chavan

[GSoC][PATCH 1/5 v3] submodule--helper: introduce get_submodule_displaypath()

[Prathamesh Chavan]

Introduce function get_submodule_displaypath() to replace the code
occurring in submodule_init() for generating displaypath of the
submodule with a call to it.

This new function will also be used in other parts of the system
in later patches.

Mentored-by: Christian Couder <christian.couder@gmail.com>
Mentored-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Prathamesh Chavan <pc44800@gmail.com>
---
The patch series is updated, and is based on 'master' branch.

This patch series contains updates patches about
Introduction of the function: get_submodule_displaypath()
(This patch wasn't posted in the last update by mistake)
Introduction of the function: for_each_submodule()
Port shell function set_name_rev() to C
Port submodule subcommand 'status' from shell to C
Port submodule subcommand 'sync' from shell to C

Complete build report of this patch-series is available at:
https://travis-ci.org/pratham-pc/git/builds
Branch: patch-series-1
Build #114

Also, the above series was also build by basing it on the 'next'
branch for the purpose of testing the code.
Since the function is_submodule_initialized changed to
is_submodule_active, this change was required to be added in the
above patches while basing it on next.
After doing the required changes,
Complete build report of the above is available at:
https://travis-ci.org/pratham-pc/git/builds
Branch: patch-series-1-next
Build #116

I have held back the following patch since some work is still
required to be done:
Port submodule subcommand 'foreach' from shell to C
Port submodule subcommand 'deinit' from shell to C
Port submodule subcommand 'summary' from shell to C
I hope to complete this and post these patches later with the
weekly updates.

 builtin/submodule--helper.c | 33 ++++++++++++++++++++++-----------
 1 file changed, 22 insertions(+), 11 deletions(-)

diff --git a/builtin/submodule--helper.c b/builtin/submodule--helper.c
index 8517032b3..1bfc91bca 100644
--- a/builtin/submodule--helper.c
+++ b/builtin/submodule--helper.c
@@ -220,6 +220,27 @@ static int resolve_relative_url_test(int argc, const char **argv, const char *pr
 	return 0;
 }
 
+static char *get_submodule_displaypath(const char *path, const char *prefix)
+{
+	const char *super_prefix = get_super_prefix();
+
+	if (prefix && super_prefix) {
+		BUG("cannot have prefix '%s' and superprefix '%s'",
+		    prefix, super_prefix);
+	} else if (prefix) {
+		struct strbuf sb = STRBUF_INIT;
+		char *displaypath = xstrdup(relative_path(path, prefix, &sb));
+		strbuf_release(&sb);
+		return displaypath;
+	} else if (super_prefix) {
+		int len = strlen(super_prefix);
+		const char *format = is_dir_sep(super_prefix[len - 1]) ? "%s%s" : "%s/%s";
+		return xstrfmt(format, super_prefix, path);
+	} else {
+		return xstrdup(path);
+	}
+}
+
 struct module_list {
 	const struct cache_entry **entries;
 	int alloc, nr;
@@ -339,16 +360,7 @@ static void init_submodule(const char *path, const char *prefix, int quiet)
 
 	/* Only loads from .gitmodules, no overlay with .git/config */
 	gitmodules_config();
-
-	if (prefix && get_super_prefix())
-		die("BUG: cannot have prefix and superprefix");
-	else if (prefix)
-		displaypath = xstrdup(relative_path(path, prefix, &sb));
-	else if (get_super_prefix()) {
-		strbuf_addf(&sb, "%s%s", get_super_prefix(), path);
-		displaypath = strbuf_detach(&sb, NULL);
-	} else
-		displaypath = xstrdup(path);
+	displaypath = get_submodule_displaypath(path, prefix);
 
 	sub = submodule_from_path(null_sha1, path);
 
@@ -363,7 +375,6 @@ static void init_submodule(const char *path, const char *prefix, int quiet)
 	 * Set active flag for the submodule being initialized
 	 */
 	if (!is_submodule_initialized(path)) {
-		strbuf_reset(&sb);
 		strbuf_addf(&sb, "submodule.%s.active", sub->name);
 		git_config_set_gently(sb.buf, "true");
 	}
-- 
2.13.0

[GSoC][PATCH 2/5 v3] submodule--helper: introduce for_each_submodule_list()

[Prathamesh Chavan]

Introduce function for_each_submodule_list() and
replace a loop in module_init() with a call to it.

The new function will also be used in other parts of the
system in later patches.

Mentored-by: Christian Couder <christian.couder@gmail.com>
Mentored-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Prathamesh Chavan <pc44800@gmail.com>
---
 builtin/submodule--helper.c | 39 +++++++++++++++++++++++++++++----------
 1 file changed, 29 insertions(+), 10 deletions(-)

diff --git a/builtin/submodule--helper.c b/builtin/submodule--helper.c
index 1bfc91bca..c4286aac5 100644
--- a/builtin/submodule--helper.c
+++ b/builtin/submodule--helper.c
@@ -14,6 +14,9 @@
 #include "refs.h"
 #include "connect.h"
 
+typedef void (*submodule_list_func_t)(const struct cache_entry *list_item,
+				      void *cb_data);
+
 static char *get_default_remote(void)
 {
 	char *dest = NULL, *ret;
@@ -352,17 +355,30 @@ static int module_list(int argc, const char **argv, const char *prefix)
 	return 0;
 }
 
-static void init_submodule(const char *path, const char *prefix, int quiet)
+static void for_each_submodule_list(const struct module_list list,
+				    submodule_list_func_t fn, void *cb_data)
 {
+	int i;
+	for (i = 0; i < list.nr; i++)
+		fn(list.entries[i], cb_data);
+}
+
+struct init_cb {
+	const char *prefix;
+	unsigned int quiet: 1;
+};
+#define INIT_CB_INIT { NULL, 0 }
+
+static void init_submodule(const struct cache_entry *list_item, void *cb_data)
+{
+	struct init_cb *info = cb_data;
 	const struct submodule *sub;
 	struct strbuf sb = STRBUF_INIT;
 	char *upd = NULL, *url = NULL, *displaypath;
 
-	/* Only loads from .gitmodules, no overlay with .git/config */
-	gitmodules_config();
-	displaypath = get_submodule_displaypath(path, prefix);
+	displaypath = get_submodule_displaypath(list_item->name, info->prefix);
 
-	sub = submodule_from_path(null_sha1, path);
+	sub = submodule_from_path(null_sha1, list_item->name);
 
 	if (!sub)
 		die(_("No url found for submodule path '%s' in .gitmodules"),
@@ -374,7 +390,7 @@ static void init_submodule(const char *path, const char *prefix, int quiet)
 	 *
 	 * Set active flag for the submodule being initialized
 	 */
-	if (!is_submodule_initialized(path)) {
+	if (!is_submodule_initialized(list_item->name)) {
 		strbuf_addf(&sb, "submodule.%s.active", sub->name);
 		git_config_set_gently(sb.buf, "true");
 	}
@@ -416,7 +432,7 @@ static void init_submodule(const char *path, const char *prefix, int quiet)
 		if (git_config_set_gently(sb.buf, url))
 			die(_("Failed to register url for submodule path '%s'"),
 			    displaypath);
-		if (!quiet)
+		if (!info->quiet)
 			fprintf(stderr,
 				_("Submodule '%s' (%s) registered for path '%s'\n"),
 				sub->name, url, displaypath);
@@ -445,10 +461,10 @@ static void init_submodule(const char *path, const char *prefix, int quiet)
 
 static int module_init(int argc, const char **argv, const char *prefix)
 {
+	struct init_cb info = INIT_CB_INIT;
 	struct pathspec pathspec;
 	struct module_list list = MODULE_LIST_INIT;
 	int quiet = 0;
-	int i;
 
 	struct option module_init_options[] = {
 		OPT__QUIET(&quiet, N_("Suppress output for initializing a submodule")),
@@ -473,8 +489,11 @@ static int module_init(int argc, const char **argv, const char *prefix)
 	if (!argc && git_config_get_value_multi("submodule.active"))
 		module_list_active(&list);
 
-	for (i = 0; i < list.nr; i++)
-		init_submodule(list.entries[i]->name, prefix, quiet);
+	info.prefix = prefix;
+	info.quiet = !!quiet;
+
+	gitmodules_config();
+	for_each_submodule_list(list, init_submodule, &info);
 
 	return 0;
 }
-- 
2.13.0

[GSoC][PATCH 3/5 v3] submodule: port set_name_rev() from shell to C

[Prathamesh Chavan]

Function set_name_rev() is ported from git-submodule to the
submodule--helper builtin. The function get_name_rev() generates the
value of the revision name as required, and the function
print_name_rev() handles the formating and printing of the obtained
revision name.

Mentored-by: Christian Couder <christian.couder@gmail.com>
Mentored-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Prathamesh Chavan <pc44800@gmail.com>
---
 builtin/submodule--helper.c | 69 +++++++++++++++++++++++++++++++++++++++++++++
 git-submodule.sh            | 16 ++---------
 2 files changed, 71 insertions(+), 14 deletions(-)

diff --git a/builtin/submodule--helper.c b/builtin/submodule--helper.c
index c4286aac5..4103e40e4 100644
--- a/builtin/submodule--helper.c
+++ b/builtin/submodule--helper.c
@@ -244,6 +244,74 @@ static char *get_submodule_displaypath(const char *path, const char *prefix)
 	}
 }
 
+enum describe_step {
+	step_bare,
+	step_tags,
+	step_contains,
+	step_all_always,
+	step_end
+};
+
+static char *get_name_rev(const char *sub_path, const char* object_id)
+{
+	struct strbuf sb = STRBUF_INIT;
+	enum describe_step cur_step;
+
+	for (cur_step = step_bare; cur_step < step_end; cur_step++) {
+		struct child_process cp = CHILD_PROCESS_INIT;
+		prepare_submodule_repo_env(&cp.env_array);
+		cp.dir = sub_path;
+		cp.git_cmd = 1;
+		cp.no_stderr = 1;
+
+		switch (cur_step) {
+			case step_bare:
+				argv_array_pushl(&cp.args, "describe",
+						 object_id, NULL);
+				break;
+			case step_tags:	
+				argv_array_pushl(&cp.args, "describe",
+						 "--tags", object_id, NULL);
+				break;
+			case step_contains:
+				argv_array_pushl(&cp.args, "describe",
+						 "--contains", object_id,
+						 NULL);
+				break;
+			case step_all_always:
+				argv_array_pushl(&cp.args, "describe",
+						 "--all", "--always",
+						 object_id, NULL);
+				break;
+			default:
+				BUG("unknown describe step '%d'", cur_step);
+		}
+
+		if (!capture_command(&cp, &sb, 0) && sb.len) {
+			strbuf_strip_suffix(&sb, "\n");
+			return strbuf_detach(&sb, NULL);
+		}
+
+	}
+
+	strbuf_release(&sb);
+	return NULL;
+}
+
+static int print_name_rev(int argc, const char **argv, const char *prefix)
+{
+	char *namerev;
+	if (argc != 3)
+		die("print-name-rev only accepts two arguments: <path> <sha1>");
+
+	namerev = get_name_rev(argv[1], argv[2]);
+	if (namerev && namerev[0])
+		printf(" (%s)", namerev);
+	printf("\n");
+
+	return 0;
+}
+
 struct module_list {
 	const struct cache_entry **entries;
 	int alloc, nr;
@@ -1242,6 +1310,7 @@ static struct cmd_struct commands[] = {
 	{"relative-path", resolve_relative_path, 0},
 	{"resolve-relative-url", resolve_relative_url, 0},
 	{"resolve-relative-url-test", resolve_relative_url_test, 0},
+	{"print-name-rev", print_name_rev, 0},
 	{"init", module_init, SUPPORT_SUPER_PREFIX},
 	{"remote-branch", resolve_remote_submodule_branch, 0},
 	{"push-check", push_check, 0},
diff --git a/git-submodule.sh b/git-submodule.sh
index e131760ee..e988167e0 100755
--- a/git-submodule.sh
+++ b/git-submodule.sh
@@ -759,18 +759,6 @@ cmd_update()
 	}
 }
 
-set_name_rev () {
-	revname=$( (
-		sanitize_submodule_env
-		cd "$1" && {
-			git describe "$2" 2>/dev/null ||
-			git describe --tags "$2" 2>/dev/null ||
-			git describe --contains "$2" 2>/dev/null ||
-			git describe --all --always "$2"
-		}
-	) )
-	test -z "$revname" || revname=" ($revname)"
-}
 #
 # Show commit summary for submodules in index or working tree
 #
@@ -1042,14 +1030,14 @@ cmd_status()
 		fi
 		if git diff-files --ignore-submodules=dirty --quiet -- "$sm_path"
 		then
-			set_name_rev "$sm_path" "$sha1"
+			revname=$(git submodule--helper print-name-rev "$sm_path" "$sha1")
 			say " $sha1 $displaypath$revname"
 		else
 			if test -z "$cached"
 			then
 				sha1=$(sanitize_submodule_env; cd "$sm_path" && git rev-parse --verify HEAD)
 			fi
-			set_name_rev "$sm_path" "$sha1"
+			revname=$(git submodule--helper print-name-rev "$sm_path" "$sha1")
 			say "+$sha1 $displaypath$revname"
 		fi
 
-- 
2.13.0

Re: [GSoC][PATCH 3/5 v3] submodule: port set_name_rev() from shell to C

[Junio C Hamano]

Prathamesh Chavan <pc44800@gmail.com> writes:

> Function set_name_rev() is ported from git-submodule to the
> submodule--helper builtin. The function get_name_rev() generates the
> value of the revision name as required, and the function
> print_name_rev() handles the formating and printing of the obtained
> revision name.
>
> Mentored-by: Christian Couder <christian.couder@gmail.com>
> Mentored-by: Stefan Beller <sbeller@google.com>
> Signed-off-by: Prathamesh Chavan <pc44800@gmail.com>
> ---
>  builtin/submodule--helper.c | 69 +++++++++++++++++++++++++++++++++++++++++++++
>  git-submodule.sh            | 16 ++---------
>  2 files changed, 71 insertions(+), 14 deletions(-)
>
> diff --git a/builtin/submodule--helper.c b/builtin/submodule--helper.c
> index c4286aac5..4103e40e4 100644
> --- a/builtin/submodule--helper.c
> +++ b/builtin/submodule--helper.c
> @@ -244,6 +244,74 @@ static char *get_submodule_displaypath(const char *path, const char *prefix)
>  	}
>  }
>  
> +enum describe_step {
> +	step_bare,
> +	step_tags,
> +	step_contains,
> +	step_all_always,
> +	step_end
> +};

Hmph.

The only difference between the steps being what subcommand is run,
a better implementation might be to do

	static const char *describe_bare[] = {
		NULL
	};

	...

	static const char **describe_argv[] = {
		describe_bare, describe_tags, describe_contains, 
                describe_all_always, NULL
	};

	const char ***d;

	for (d = describe_argv; *d; d++) {
		argv_array_pushl(&cp.args, "describe");
		argv_array_pushv(&cp.args, *d);
		... do the thing ...
	}

but unfortunately C is a bit klunky to do so; we cannot easily make
the contents of describe_argv[] as anonymous arrays.  An otherwise
useless enum stil bothers me, but I do not think of anything better
offhand.

> +
> +static char *get_name_rev(const char *sub_path, const char* object_id)
> +{
> +	struct strbuf sb = STRBUF_INIT;
> +	enum describe_step cur_step;
> +
> +	for (cur_step = step_bare; cur_step < step_end; cur_step++) {
> +		struct child_process cp = CHILD_PROCESS_INIT;
> +		prepare_submodule_repo_env(&cp.env_array);
> +		cp.dir = sub_path;
> +		cp.git_cmd = 1;
> +		cp.no_stderr = 1;
> +
> +		switch (cur_step) {
> +			case step_bare:
> +				argv_array_pushl(&cp.args, "describe",
> +						 object_id, NULL);
> +				break;
> +			case step_tags:	
> +				argv_array_pushl(&cp.args, "describe",
> +						 "--tags", object_id, NULL);
> +				break;
> +			case step_contains:
> +				argv_array_pushl(&cp.args, "describe",
> +						 "--contains", object_id,
> +						 NULL);
> +				break;
> +			case step_all_always:
> +				argv_array_pushl(&cp.args, "describe",
> +						 "--all", "--always",
> +						 object_id, NULL);
> +				break;
> +			default:
> +				BUG("unknown describe step '%d'", cur_step);
> +		}

Dedent the body of switch() by one level, i.e.

	switch (var) {
	case val1:
		do_this();
		break;
	case val2:
		do_that();
		...
	}

Otherwise looking good.

> @@ -1042,14 +1030,14 @@ cmd_status()
>  		fi
>  		if git diff-files --ignore-submodules=dirty --quiet -- "$sm_path"
>  		then
> -			set_name_rev "$sm_path" "$sha1"
> +			revname=$(git submodule--helper print-name-rev "$sm_path" "$sha1")
>  			say " $sha1 $displaypath$revname"
>  		else
>  			if test -z "$cached"
>  			then
>  				sha1=$(sanitize_submodule_env; cd "$sm_path" && git rev-parse --verify HEAD)
>  			fi
> -			set_name_rev "$sm_path" "$sha1"
> +			revname=$(git submodule--helper print-name-rev "$sm_path" "$sha1")
>  			say "+$sha1 $displaypath$revname"
>  		fi

[GSoC][PATCH 4/5 v3] submodule: port submodule subcommand 'status' from shell to C

[Prathamesh Chavan]

This aims to make git-submodule 'status' a built-in. Hence, the function
cmd_status() is ported from shell to C. This is done by introducing
three functions: module_status(), submodule_status() and print_status().

The function module_status() acts as the front-end of the subcommand.
It parses subcommand's options and then calls the function
module_list_compute() for computing the list of submodules. Then
this functions calls for_each_submodule_list() looping through the
list obtained.

Then for_each_submodule_list() calls submodule_status() for each of the
submodule in its list. The function submodule_status() is responsible
for generating the status each submodule it is called for, and
then calls print_status().

Finally, the function print_status() handles the printing of submodule's
status.

Mentored-by: Christian Couder <christian.couder@gmail.com>
Mentored-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Prathamesh Chavan <pc44800@gmail.com>
---
 builtin/submodule--helper.c | 152 ++++++++++++++++++++++++++++++++++++++++++++
 git-submodule.sh            |  49 +-------------
 2 files changed, 153 insertions(+), 48 deletions(-)

diff --git a/builtin/submodule--helper.c b/builtin/submodule--helper.c
index 4103e40e4..575ae0218 100644
--- a/builtin/submodule--helper.c
+++ b/builtin/submodule--helper.c
@@ -566,6 +566,157 @@ static int module_init(int argc, const char **argv, const char *prefix)
 	return 0;
 }
 
+struct status_cb {
+	const char *prefix;
+	unsigned int quiet: 1;
+	unsigned int recursive: 1;
+	unsigned int cached: 1;
+};
+#define STATUS_CB_INIT { NULL, 0, 0, 0 }
+
+static void print_status(struct status_cb *info, char state, const char *path,
+			 char *sub_sha1, char *displaypath)
+{
+	if (info->quiet)
+		return;
+
+	printf("%c%s %s", state, sub_sha1, displaypath);
+
+	if (state == ' ' || state == '+') {
+		struct argv_array name_rev_args = ARGV_ARRAY_INIT;
+
+		argv_array_pushl(&name_rev_args, "print-name-rev",
+				 path, sub_sha1, NULL);
+		print_name_rev(name_rev_args.argc, name_rev_args.argv,
+			       info->prefix);
+	} else {
+		printf("\n");
+	}
+}
+
+static void status_submodule(const struct cache_entry *list_item, void *cb_data)
+{
+	struct status_cb *info = cb_data;
+	char *sub_sha1 = xstrdup(oid_to_hex(&list_item->oid));
+	char *displaypath;
+	struct argv_array diff_files_args = ARGV_ARRAY_INIT;
+
+	if (!submodule_from_path(null_sha1, list_item->name))
+		die(_("no submodule mapping found in .gitmodules for path '%s'"),
+		      list_item->name);
+
+	displaypath = get_submodule_displaypath(list_item->name, info->prefix);
+
+	if (list_item->ce_flags) {
+		print_status(info, 'U', list_item->name,
+			     sha1_to_hex(null_sha1), displaypath);
+		goto cleanup;
+	}
+
+	if (!is_submodule_initialized(list_item->name)) {
+		print_status(info, '-', list_item->name, sub_sha1, displaypath);
+		goto cleanup;
+	}
+
+	argv_array_pushl(&diff_files_args, "diff-files",
+			 "--ignore-submodules=dirty", "--quiet", "--",
+			 list_item->name, NULL);
+
+	if (!cmd_diff_files(diff_files_args.argc, diff_files_args.argv,
+			    info->prefix)) {
+		print_status(info, ' ', list_item->name, sub_sha1, displaypath);
+	} else {
+		if (!info->cached) {
+			struct child_process cp = CHILD_PROCESS_INIT;
+			struct strbuf sb = STRBUF_INIT;
+
+			prepare_submodule_repo_env(&cp.env_array);
+			cp.git_cmd = 1;
+			cp.dir = list_item->name;
+
+			argv_array_pushl(&cp.args, "rev-parse",
+					 "--verify", "HEAD", NULL);
+
+			if (capture_command(&cp, &sb, 0))
+				die(_("could not run 'git rev-parse --verify"
+				      "HEAD' in submodule %s"),
+				      list_item->name);
+
+			strbuf_strip_suffix(&sb, "\n");
+			print_status(info, '+', list_item->name, sb.buf,
+				     displaypath);
+			strbuf_release(&sb);
+		} else {
+			print_status(info, '+', list_item->name, sub_sha1,
+				     displaypath);
+		}
+	}
+
+	if (info->recursive) {
+		struct child_process cpr = CHILD_PROCESS_INIT;
+
+		cpr.git_cmd = 1;
+		cpr.dir = list_item->name;
+		prepare_submodule_repo_env(&cpr.env_array);
+
+		argv_array_pushl(&cpr.args, "--super-prefix", displaypath,
+				 "submodule--helper", "status", "--recursive",
+				 NULL);
+
+		if (info->cached)
+			argv_array_push(&cpr.args, "--cached");
+
+		if (info->quiet)
+			argv_array_push(&cpr.args, "--quiet");
+
+		if (run_command(&cpr))
+			die(_("failed to recurse into submodule '%s'"),
+			      list_item->name);
+	}
+
+cleanup:
+	free(displaypath);
+	free(sub_sha1);
+}
+
+static int module_status(int argc, const char **argv, const char *prefix)
+{
+	struct status_cb info = STATUS_CB_INIT;
+	struct pathspec pathspec;
+	struct module_list list = MODULE_LIST_INIT;
+	int quiet = 0;
+	int cached = 0;
+	int recursive = 0;
+
+	struct option module_status_options[] = {
+		OPT__QUIET(&quiet, N_("Suppress submodule status output")),
+		OPT_BOOL(0, "cached", &cached, N_("Use commit stored in the index instead of the one stored in the submodule HEAD")),
+		OPT_BOOL(0, "recursive", &recursive, N_("Recurse into nested submodules")),
+		OPT_END()
+	};
+
+	const char *const git_submodule_helper_usage[] = {
+		N_("git submodule status [--quiet] [--cached] [--recursive] [<path>]"),
+		NULL
+	};
+
+	argc = parse_options(argc, argv, prefix, module_status_options,
+			     git_submodule_helper_usage, 0);
+
+	if (module_list_compute(argc, argv, prefix, &pathspec, &list) < 0)
+		return 1;
+
+	info.prefix = prefix;
+	info.quiet = !!quiet;
+	info.recursive = !!recursive;
+	info.cached = !!cached;
+
+	gitmodules_config();
+	for_each_submodule_list(list, status_submodule, &info);
+
+	return 0;
+}
+
 static int module_name(int argc, const char **argv, const char *prefix)
 {
 	const struct submodule *sub;
@@ -1312,6 +1463,7 @@ static struct cmd_struct commands[] = {
 	{"resolve-relative-url-test", resolve_relative_url_test, 0},
 	{"print-name-rev", print_name_rev, 0},
 	{"init", module_init, SUPPORT_SUPER_PREFIX},
+	{"status", module_status, SUPPORT_SUPER_PREFIX},
 	{"remote-branch", resolve_remote_submodule_branch, 0},
 	{"push-check", push_check, 0},
 	{"absorb-git-dirs", absorb_git_dirs, SUPPORT_SUPER_PREFIX},
diff --git a/git-submodule.sh b/git-submodule.sh
index e988167e0..51b057d82 100755
--- a/git-submodule.sh
+++ b/git-submodule.sh
@@ -1005,54 +1005,7 @@ cmd_status()
 		shift
 	done
 
-	{
-		git submodule--helper list --prefix "$wt_prefix" "$@" ||
-		echo "#unmatched" $?
-	} |
-	while read -r mode sha1 stage sm_path
-	do
-		die_if_unmatched "$mode" "$sha1"
-		name=$(git submodule--helper name "$sm_path") || exit
-		displaypath=$(git submodule--helper relative-path "$prefix$sm_path" "$wt_prefix")
-		if test "$stage" = U
-		then
-			say "U$sha1 $displaypath"
-			continue
-		fi
-		if ! git submodule--helper is-active "$sm_path" ||
-		{
-			! test -d "$sm_path"/.git &&
-			! test -f "$sm_path"/.git
-		}
-		then
-			say "-$sha1 $displaypath"
-			continue;
-		fi
-		if git diff-files --ignore-submodules=dirty --quiet -- "$sm_path"
-		then
-			revname=$(git submodule--helper print-name-rev "$sm_path" "$sha1")
-			say " $sha1 $displaypath$revname"
-		else
-			if test -z "$cached"
-			then
-				sha1=$(sanitize_submodule_env; cd "$sm_path" && git rev-parse --verify HEAD)
-			fi
-			revname=$(git submodule--helper print-name-rev "$sm_path" "$sha1")
-			say "+$sha1 $displaypath$revname"
-		fi
-
-		if test -n "$recursive"
-		then
-			(
-				prefix="$displaypath/"
-				sanitize_submodule_env
-				wt_prefix=
-				cd "$sm_path" &&
-				eval cmd_status
-			) ||
-			die "$(eval_gettext "Failed to recurse into submodule path '\$sm_path'")"
-		fi
-	done
+	git ${wt_prefix:+-C "$wt_prefix"} ${prefix:+--super-prefix "$prefix"} submodule--helper status ${GIT_QUIET:+--quiet} ${cached:+--cached} ${recursive:+--recursive} "$@"
 }
 #
 # Sync remote urls for submodules
-- 
2.13.0

Re: [GSoC][PATCH 4/5 v3] submodule: port submodule subcommand 'status' from shell to C

[Junio C Hamano]

Prathamesh Chavan <pc44800@gmail.com> writes:

> +	argv_array_pushl(&diff_files_args, "diff-files",
> +			 "--ignore-submodules=dirty", "--quiet", "--",
> +			 list_item->name, NULL);
> +
> +	if (!cmd_diff_files(diff_files_args.argc, diff_files_args.argv,
> +			    info->prefix)) {

Essentially we'd only want to run ce_match_stat() on list_item and
the current on-filesystem submodule.  We not just know which path we
are interested in, but we already have the cache entry for it, so it
feels quite wasteful to go over the_index.cache[] once again to find
the cache entry that matches list_item->name.  Yes, that is how the
scripted Porcelain did it, but it feels way overkill now we have
ready access to the lower level machinery.

Having said all that, I think it is a good idea to stick to a
faithful conversion in this series.  I just think a NEEDSWORK
comment may be a good idea to indicate future optimization
opportunities.

A similar optimization is already happening in this patch, actually.
Instead of doing a stat of "$sm_path/.git" and checking test -d/-f,
the code just calls is_submodule_initialized().  Which is good ;-)

> +	} else {
> +		if (!info->cached) {
> +			struct child_process cp = CHILD_PROCESS_INIT;
> +			struct strbuf sb = STRBUF_INIT;
> +
> +			prepare_submodule_repo_env(&cp.env_array);
> +			cp.git_cmd = 1;
> +			cp.dir = list_item->name;
> +
> +			argv_array_pushl(&cp.args, "rev-parse",
> +					 "--verify", "HEAD", NULL);
> +
> +			if (capture_command(&cp, &sb, 0))
> +				die(_("could not run 'git rev-parse --verify"
> +				      "HEAD' in submodule %s"),
> +				      list_item->name);
> +
> +			strbuf_strip_suffix(&sb, "\n");

Likewise.  This is merely resolving a ref inside a submodule;
calling something like head_ref_submodule() may be sufficient
as an optimization and at least deserves to be mentioned in a
NEEDSWORK comment.

> +			print_status(info, '+', list_item->name, sb.buf,
> +				     displaypath);
> +			strbuf_release(&sb);
> +		} else {
> +			print_status(info, '+', list_item->name, sub_sha1,
> +				     displaypath);
> +		}
> +	}

[GSoC][PATCH 5/5 v3] submodule: port submodule subcommand 'sync' from shell to C

[Prathamesh Chavan]

Port the submodule subcommand 'sync' from shell to C using the same
mechanism as that used for porting submodule subcommand 'status'.
Hence, here the function cmd_sync() is ported from shell to C.
This is done by introducing three functions: module_sync(),
sync_submodule() and print_default_remote().

The function print_default_remote() is introduced for getting
the default remote as stdout.

Mentored-by: Christian Couder <christian.couder@gmail.com>
Mentored-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Prathamesh Chavan <pc44800@gmail.com>
---
 builtin/submodule--helper.c | 177 ++++++++++++++++++++++++++++++++++++++++++++
 git-submodule.sh            |  56 +-------------
 2 files changed, 178 insertions(+), 55 deletions(-)

diff --git a/builtin/submodule--helper.c b/builtin/submodule--helper.c
index 575ae0218..d933daadd 100644
--- a/builtin/submodule--helper.c
+++ b/builtin/submodule--helper.c
@@ -44,6 +44,20 @@ static char *get_default_remote(void)
 	return ret;
 }
 
+static int print_default_remote(int argc, const char **argv, const char *prefix)
+{
+	const char *remote;
+
+	if (argc != 1)
+		die(_("submodule--helper print-default-remote takes no arguments"));
+
+	remote = get_default_remote();
+	if (remote)
+		puts(remote);
+
+	return 0;
+}
+
 static int starts_with_dot_slash(const char *str)
 {
 	return str[0] == '.' && is_dir_sep(str[1]);
@@ -385,6 +399,25 @@ static void module_list_active(struct module_list *list)
 	*list = active_modules;
 }
 
+static char *get_up_path(const char *path)
+{
+	int i;
+	struct strbuf sb = STRBUF_INIT;
+
+	for (i = count_slashes(path); i; i--)
+		strbuf_addstr(&sb, "../");
+
+	/*
+	 * Check if 'path' ends with slash or not
+	 * for having the same output for dir/sub_dir
+	 * and dir/sub_dir/
+	 */
+	if (!is_dir_sep(path[strlen(path) - 1]))
+		strbuf_addstr(&sb, "../");
+
+	return strbuf_detach(&sb, NULL);
+}
+
 static int module_list(int argc, const char **argv, const char *prefix)
 {
 	int i;
@@ -736,6 +769,148 @@ static int module_name(int argc, const char **argv, const char *prefix)
 	return 0;
 }
 
+struct sync_cb {
+	const char *prefix;
+	unsigned int quiet: 1;
+	unsigned int recursive: 1;
+};
+#define SYNC_CB_INIT { NULL, 0, 0 }
+
+static void sync_submodule(const struct cache_entry *list_item, void *cb_data)
+{
+	struct sync_cb *info = cb_data;
+	const struct submodule *sub;
+	char *sub_key, *remote_key;
+	char *sub_origin_url, *super_config_url, *displaypath;
+	struct strbuf sb = STRBUF_INIT;
+	struct child_process cp = CHILD_PROCESS_INIT;
+
+	if (!is_submodule_initialized(list_item->name))
+		return;
+
+	sub = submodule_from_path(null_sha1, list_item->name);
+
+	if (!sub || !sub->url)
+		die(_("no url found for submodule path '%s' in .gitmodules"),
+		      list_item->name);
+
+	if (starts_with_dot_dot_slash(sub->url) || starts_with_dot_slash(sub->url)) {
+		char *remote_url, *up_path;
+		char *remote = get_default_remote();
+		char *remote_key = xstrfmt("remote.%s.url", remote);
+		free(remote);
+
+		if (git_config_get_string(remote_key, &remote_url))
+			remote_url = xgetcwd();
+		up_path = get_up_path(list_item->name);
+		sub_origin_url = relative_url(remote_url, sub->url, up_path);
+		super_config_url = relative_url(remote_url, sub->url, NULL);
+		free(remote_key);
+		free(up_path);
+		free(remote_url);
+	} else {
+		sub_origin_url = xstrdup(sub->url);
+		super_config_url = xstrdup(sub->url);
+	}
+
+	displaypath = get_submodule_displaypath(list_item->name, info->prefix);
+
+	if (!info->quiet)
+		printf(_("Synchronizing submodule url for '%s'\n"),
+			 displaypath);
+
+	sub_key = xstrfmt("submodule.%s.url", sub->name);
+	if (git_config_set_gently(sub_key, super_config_url))
+		die(_("failed to register url for submodule path '%s'"),
+		      displaypath);
+
+	if (!is_submodule_populated_gently(list_item->name, NULL))
+		goto cleanup;
+
+	prepare_submodule_repo_env(&cp.env_array);
+	cp.git_cmd = 1;
+	cp.dir = list_item->name;
+	argv_array_pushl(&cp.args, "submodule--helper",
+			 "print-default-remote", NULL);
+	if (capture_command(&cp, &sb, 0))
+		die(_("failed to get the default remote for submodule '%s'"),
+		      list_item->name);
+
+	strbuf_strip_suffix(&sb, "\n");
+	remote_key = xstrfmt("remote.%s.url", sb.buf);
+	strbuf_release(&sb);
+
+	child_process_init(&cp);
+	prepare_submodule_repo_env(&cp.env_array);
+	cp.git_cmd = 1;
+	cp.dir = list_item->name;
+	argv_array_pushl(&cp.args, "config", remote_key, sub_origin_url, NULL);
+	if (run_command(&cp))
+		die(_("failed to update remote for submodule '%s'"),
+		      list_item->name);
+
+	if (info->recursive) {
+		struct child_process cpr = CHILD_PROCESS_INIT;
+
+		cpr.git_cmd = 1;
+		cpr.dir = list_item->name;
+		prepare_submodule_repo_env(&cpr.env_array);
+
+		argv_array_pushl(&cpr.args, "--super-prefix", displaypath,
+				 "submodule--helper", "sync", "--recursive",
+				 NULL);
+
+		if (info->quiet)
+			argv_array_push(&cpr.args, "--quiet");
+
+		if (run_command(&cpr))
+			die(_("failed to recurse into submodule '%s'"),
+			      list_item->name);
+	}
+
+cleanup:
+	free(sub_key);
+	free(super_config_url);
+	free(displaypath);
+	free(sub_origin_url);
+}
+
+static int module_sync(int argc, const char **argv, const char *prefix)
+{
+	struct sync_cb info = SYNC_CB_INIT;
+	struct pathspec pathspec;
+	struct module_list list = MODULE_LIST_INIT;
+	int quiet = 0;
+	int recursive = 0;
+
+	struct option module_sync_options[] = {
+		OPT__QUIET(&quiet, N_("Suppress output of synchronizing submodule url")),
+		OPT_BOOL(0, "recursive", &recursive,
+			N_("Recurse into nested submodules")),
+		OPT_END()
+	};
+
+	const char *const git_submodule_helper_usage[] = {
+		N_("git submodule--helper sync [--quiet] [--recursive] [<path>]"),
+		NULL
+	};
+
+	argc = parse_options(argc, argv, prefix, module_sync_options,
+			     git_submodule_helper_usage, 0);
+
+	if (module_list_compute(argc, argv, prefix, &pathspec, &list) < 0)
+		return 1;
+
+	info.prefix = prefix;
+	info.quiet = !!quiet;
+	info.recursive = !!recursive;
+
+	gitmodules_config();
+	for_each_submodule_list(list, sync_submodule, &info);
+
+	return 0;
+}
+
 static int clone_submodule(const char *path, const char *gitdir, const char *url,
 			   const char *depth, struct string_list *reference,
 			   int quiet, int progress)
@@ -1464,6 +1639,8 @@ static struct cmd_struct commands[] = {
 	{"print-name-rev", print_name_rev, 0},
 	{"init", module_init, SUPPORT_SUPER_PREFIX},
 	{"status", module_status, SUPPORT_SUPER_PREFIX},
+	{"print-default-remote", print_default_remote, 0},
+	{"sync", module_sync, SUPPORT_SUPER_PREFIX},
 	{"remote-branch", resolve_remote_submodule_branch, 0},
 	{"push-check", push_check, 0},
 	{"absorb-git-dirs", absorb_git_dirs, SUPPORT_SUPER_PREFIX},
diff --git a/git-submodule.sh b/git-submodule.sh
index 51b057d82..6bfc5e17d 100755
--- a/git-submodule.sh
+++ b/git-submodule.sh
@@ -1037,63 +1037,9 @@ cmd_sync()
 			;;
 		esac
 	done
-	cd_to_toplevel
-	{
-		git submodule--helper list --prefix "$wt_prefix" "$@" ||
-		echo "#unmatched" $?
-	} |
-	while read -r mode sha1 stage sm_path
-	do
-		die_if_unmatched "$mode" "$sha1"
-
-		# skip inactive submodules
-		if ! git submodule--helper is-active "$sm_path"
-		then
-			continue
-		fi
-
-		name=$(git submodule--helper name "$sm_path")
-		url=$(git config -f .gitmodules --get submodule."$name".url)
-
-		# Possibly a url relative to parent
-		case "$url" in
-		./*|../*)
-			# rewrite foo/bar as ../.. to find path from
-			# submodule work tree to superproject work tree
-			up_path="$(printf '%s\n' "$sm_path" | sed "s/[^/][^/]*/../g")" &&
-			# guarantee a trailing /
-			up_path=${up_path%/}/ &&
-			# path from submodule work tree to submodule origin repo
-			sub_origin_url=$(git submodule--helper resolve-relative-url "$url" "$up_path") &&
-			# path from superproject work tree to submodule origin repo
-			super_config_url=$(git submodule--helper resolve-relative-url "$url") || exit
-			;;
-		*)
-			sub_origin_url="$url"
-			super_config_url="$url"
-			;;
-		esac
 
-		displaypath=$(git submodule--helper relative-path "$prefix$sm_path" "$wt_prefix")
-		say "$(eval_gettext "Synchronizing submodule url for '\$displaypath'")"
-		git config submodule."$name".url "$super_config_url"
-
-		if test -e "$sm_path"/.git
-		then
-		(
-			sanitize_submodule_env
-			cd "$sm_path"
-			remote=$(get_default_remote)
-			git config remote."$remote".url "$sub_origin_url"
+	git ${wt_prefix:+-C "$wt_prefix"} ${prefix:+--super-prefix "$prefix"} submodule--helper sync ${GIT_QUIET:+--quiet} ${recursive:+--recursive} "$@"
 
-			if test -n "$recursive"
-			then
-				prefix="$prefix$sm_path/"
-				eval cmd_sync
-			fi
-		)
-		fi
-	done
 }
 
 cmd_absorbgitdirs()
-- 
2.13.0

Re: [GSoC][PATCH 5/5 v3] submodule: port submodule subcommand 'sync' from shell to C

[Stefan Beller]

On Fri, Jun 30, 2017 at 12:47 PM, Prathamesh Chavan <pc44800@gmail.com> wrote:
> Port the submodule subcommand 'sync' from shell to C using the same
> mechanism as that used for porting submodule subcommand 'status'.
> Hence, here the function cmd_sync() is ported from shell to C.
> This is done by introducing three functions: module_sync(),
> sync_submodule() and print_default_remote().
>
> The function print_default_remote() is introduced for getting
> the default remote as stdout.
>
> Mentored-by: Christian Couder <christian.couder@gmail.com>
> Mentored-by: Stefan Beller <sbeller@google.com>
> Signed-off-by: Prathamesh Chavan <pc44800@gmail.com>
> ---

All these patches are also
Reviewed-by: Stefan Beller <sbeller@google.com>

Thanks for upstreaming the early parts.

Thanks,
Stefan

Re: [GSoC][PATCH 5/5 v3] submodule: port submodule subcommand 'sync' from shell to C

[Junio C Hamano]

Prathamesh Chavan <pc44800@gmail.com> writes:

> +static void sync_submodule(const struct cache_entry *list_item, void *cb_data)
> +{
> +	struct sync_cb *info = cb_data;
> +	const struct submodule *sub;
> +	char *sub_key, *remote_key;
> +	char *sub_origin_url, *super_config_url, *displaypath;
> +	struct strbuf sb = STRBUF_INIT;
> +	struct child_process cp = CHILD_PROCESS_INIT;
> +
> +	if (!is_submodule_initialized(list_item->name))
> +		return;
> +
> +	sub = submodule_from_path(null_sha1, list_item->name);
> +
> +	if (!sub || !sub->url)
> +		die(_("no url found for submodule path '%s' in .gitmodules"),
> +		      list_item->name);
> +
> +	if (starts_with_dot_dot_slash(sub->url) || starts_with_dot_slash(sub->url)) {
> +		char *remote_url, *up_path;
> +		char *remote = get_default_remote();
> +		char *remote_key = xstrfmt("remote.%s.url", remote);
> +		free(remote);
> +

Have a blank line between the decls and the first statement
(i.e. before "free(remote)").  The blank line after "free(remote)"
may or may not be there.

> +		if (git_config_get_string(remote_key, &remote_url))
> +			remote_url = xgetcwd();
> +...
> +
> +	prepare_submodule_repo_env(&cp.env_array);
> +	cp.git_cmd = 1;
> +	cp.dir = list_item->name;
> +	argv_array_pushl(&cp.args, "submodule--helper",
> +			 "print-default-remote", NULL);
> +	if (capture_command(&cp, &sb, 0))
> +		die(_("failed to get the default remote for submodule '%s'"),
> +		      list_item->name);

OK.  Perhaps in a distant future when the repository object
abstraction is ready, we can do this within the main process, but
for now, due to the presence of cp.dir, this is the best we can do.

> +	strbuf_strip_suffix(&sb, "\n");
> +	remote_key = xstrfmt("remote.%s.url", sb.buf);
> +	strbuf_release(&sb);
> +
> +	child_process_init(&cp);
> +	prepare_submodule_repo_env(&cp.env_array);
> +	cp.git_cmd = 1;
> +	cp.dir = list_item->name;
> +	argv_array_pushl(&cp.args, "config", remote_key, sub_origin_url, NULL);
> +	if (run_command(&cp))
> +		die(_("failed to update remote for submodule '%s'"),
> +		      list_item->name);

Likewise.

Looks like a fairly faithful conversion to me.

Thanks.

Re: [GSoC][PATCH 1/5 v3] submodule--helper: introduce get_submodule_displaypath()

[Junio C Hamano]

Prathamesh Chavan <pc44800@gmail.com> writes:

> Introduce function get_submodule_displaypath() to replace the code
> occurring in submodule_init() for generating displaypath of the
> submodule with a call to it.
>
> This new function will also be used in other parts of the system
> in later patches.
>
> Mentored-by: Christian Couder <christian.couder@gmail.com>
> Mentored-by: Stefan Beller <sbeller@google.com>
> Signed-off-by: Prathamesh Chavan <pc44800@gmail.com>
> ---
> The patch series is updated, and is based on 'master' branch.
>
> This patch series contains updates patches about
> Introduction of the function: get_submodule_displaypath()
> (This patch wasn't posted in the last update by mistake)

I was wondering what that thing was while reading the previous
round.  Good that it now appears in this round of the series ;-)

Thanks.

[GSoC][PATCH 1/5 v4] submodule--helper: introduce get_submodule_displaypath()

[Prathamesh Chavan]

Introduce function get_submodule_displaypath() to replace the code
occurring in submodule_init() for generating displaypath of the
submodule with a call to it.

This new function will also be used in other parts of the system
in later patches.

Mentored-by: Christian Couder <christian.couder@gmail.com>
Mentored-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Prathamesh Chavan <pc44800@gmail.com>
---
 builtin/submodule--helper.c | 33 ++++++++++++++++++++++-----------
 1 file changed, 22 insertions(+), 11 deletions(-)

diff --git a/builtin/submodule--helper.c b/builtin/submodule--helper.c
index 6abdad329..7af4de09b 100644
--- a/builtin/submodule--helper.c
+++ b/builtin/submodule--helper.c
@@ -220,6 +220,27 @@ static int resolve_relative_url_test(int argc, const char **argv, const char *pr
 	return 0;
 }
 
+static char *get_submodule_displaypath(const char *path, const char *prefix)
+{
+	const char *super_prefix = get_super_prefix();
+
+	if (prefix && super_prefix) {
+		BUG("cannot have prefix '%s' and superprefix '%s'",
+		    prefix, super_prefix);
+	} else if (prefix) {
+		struct strbuf sb = STRBUF_INIT;
+		char *displaypath = xstrdup(relative_path(path, prefix, &sb));
+		strbuf_release(&sb);
+		return displaypath;
+	} else if (super_prefix) {
+		int len = strlen(super_prefix);
+		const char *format = is_dir_sep(super_prefix[len - 1]) ? "%s%s" : "%s/%s";
+		return xstrfmt(format, super_prefix, path);
+	} else {
+		return xstrdup(path);
+	}
+}
+
 struct module_list {
 	const struct cache_entry **entries;
 	int alloc, nr;
@@ -339,16 +360,7 @@ static void init_submodule(const char *path, const char *prefix, int quiet)
 
 	/* Only loads from .gitmodules, no overlay with .git/config */
 	gitmodules_config();
-
-	if (prefix && get_super_prefix())
-		die("BUG: cannot have prefix and superprefix");
-	else if (prefix)
-		displaypath = xstrdup(relative_path(path, prefix, &sb));
-	else if (get_super_prefix()) {
-		strbuf_addf(&sb, "%s%s", get_super_prefix(), path);
-		displaypath = strbuf_detach(&sb, NULL);
-	} else
-		displaypath = xstrdup(path);
+	displaypath = get_submodule_displaypath(path, prefix);
 
 	sub = submodule_from_path(null_sha1, path);
 
@@ -363,7 +375,6 @@ static void init_submodule(const char *path, const char *prefix, int quiet)
 	 * Set active flag for the submodule being initialized
 	 */
 	if (!is_submodule_active(the_repository, path)) {
-		strbuf_reset(&sb);
 		strbuf_addf(&sb, "submodule.%s.active", sub->name);
 		git_config_set_gently(sb.buf, "true");
 	}
-- 
2.13.0

[GSoC][PATCH 2/5 v4] submodule--helper: introduce for_each_submodule_list()

[Prathamesh Chavan]

Introduce function for_each_submodule_list() and
replace a loop in module_init() with a call to it.

The new function will also be used in other parts of the
system in later patches.

Mentored-by: Christian Couder <christian.couder@gmail.com>
Mentored-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Prathamesh Chavan <pc44800@gmail.com>
---
 builtin/submodule--helper.c | 39 +++++++++++++++++++++++++++++----------
 1 file changed, 29 insertions(+), 10 deletions(-)

diff --git a/builtin/submodule--helper.c b/builtin/submodule--helper.c
index 7af4de09b..e41572f7a 100644
--- a/builtin/submodule--helper.c
+++ b/builtin/submodule--helper.c
@@ -14,6 +14,9 @@
 #include "refs.h"
 #include "connect.h"
 
+typedef void (*submodule_list_func_t)(const struct cache_entry *list_item,
+				      void *cb_data);
+
 static char *get_default_remote(void)
 {
 	char *dest = NULL, *ret;
@@ -352,17 +355,30 @@ static int module_list(int argc, const char **argv, const char *prefix)
 	return 0;
 }
 
-static void init_submodule(const char *path, const char *prefix, int quiet)
+static void for_each_submodule_list(const struct module_list list,
+				    submodule_list_func_t fn, void *cb_data)
 {
+	int i;
+	for (i = 0; i < list.nr; i++)
+		fn(list.entries[i], cb_data);
+}
+
+struct init_cb {
+	const char *prefix;
+	unsigned int quiet: 1;
+};
+#define INIT_CB_INIT { NULL, 0 }
+
+static void init_submodule(const struct cache_entry *list_item, void *cb_data)
+{
+	struct init_cb *info = cb_data;
 	const struct submodule *sub;
 	struct strbuf sb = STRBUF_INIT;
 	char *upd = NULL, *url = NULL, *displaypath;
 
-	/* Only loads from .gitmodules, no overlay with .git/config */
-	gitmodules_config();
-	displaypath = get_submodule_displaypath(path, prefix);
+	displaypath = get_submodule_displaypath(list_item->name, info->prefix);
 
-	sub = submodule_from_path(null_sha1, path);
+	sub = submodule_from_path(null_sha1, list_item->name);
 
 	if (!sub)
 		die(_("No url found for submodule path '%s' in .gitmodules"),
@@ -374,7 +390,7 @@ static void init_submodule(const char *path, const char *prefix, int quiet)
 	 *
 	 * Set active flag for the submodule being initialized
 	 */
-	if (!is_submodule_active(the_repository, path)) {
+	if (!is_submodule_active(the_repository, list_item->name)) {
 		strbuf_addf(&sb, "submodule.%s.active", sub->name);
 		git_config_set_gently(sb.buf, "true");
 	}
@@ -416,7 +432,7 @@ static void init_submodule(const char *path, const char *prefix, int quiet)
 		if (git_config_set_gently(sb.buf, url))
 			die(_("Failed to register url for submodule path '%s'"),
 			    displaypath);
-		if (!quiet)
+		if (!info->quiet)
 			fprintf(stderr,
 				_("Submodule '%s' (%s) registered for path '%s'\n"),
 				sub->name, url, displaypath);
@@ -445,10 +461,10 @@ static void init_submodule(const char *path, const char *prefix, int quiet)
 
 static int module_init(int argc, const char **argv, const char *prefix)
 {
+	struct init_cb info = INIT_CB_INIT;
 	struct pathspec pathspec;
 	struct module_list list = MODULE_LIST_INIT;
 	int quiet = 0;
-	int i;
 
 	struct option module_init_options[] = {
 		OPT__QUIET(&quiet, N_("Suppress output for initializing a submodule")),
@@ -473,8 +489,11 @@ static int module_init(int argc, const char **argv, const char *prefix)
 	if (!argc && git_config_get_value_multi("submodule.active"))
 		module_list_active(&list);
 
-	for (i = 0; i < list.nr; i++)
-		init_submodule(list.entries[i]->name, prefix, quiet);
+	info.prefix = prefix;
+	info.quiet = !!quiet;
+
+	gitmodules_config();
+	for_each_submodule_list(list, init_submodule, &info);
 
 	return 0;
 }
-- 
2.13.0

[GSoC][PATCH 3/5 v4] submodule: port set_name_rev() from shell to C

[Prathamesh Chavan]

Function set_name_rev() is ported from git-submodule to the
submodule--helper builtin. The function get_name_rev() generates the
value of the revision name as required, and the function
print_name_rev() handles the formating and printing of the obtained
revision name.

Mentored-by: Christian Couder <christian.couder@gmail.com>
Mentored-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Prathamesh Chavan <pc44800@gmail.com>
---
 builtin/submodule--helper.c | 63 +++++++++++++++++++++++++++++++++++++++++++++
 git-submodule.sh            | 16 ++----------
 2 files changed, 65 insertions(+), 14 deletions(-)

diff --git a/builtin/submodule--helper.c b/builtin/submodule--helper.c
index e41572f7a..80f744407 100644
--- a/builtin/submodule--helper.c
+++ b/builtin/submodule--helper.c
@@ -244,6 +244,68 @@ static char *get_submodule_displaypath(const char *path, const char *prefix)
 	}
 }
 
+static char *get_name_rev(const char *sub_path, const char* object_id)
+{
+	struct strbuf sb = STRBUF_INIT;
+	const char ***d;
+
+	static const char *describe_bare[] = {
+		NULL
+	};
+
+	static const char *describe_tags[] = {
+		"--tags", NULL
+	};
+
+	static const char *describe_contains[] = {
+		"--contains", NULL
+	};
+
+	static const char *describe_all_always[] = {
+		"--all", "--always", NULL
+	};
+
+	static const char **describe_argv[] = {
+		describe_bare, describe_tags, describe_contains,
+		describe_all_always, NULL
+	};
+
+	for (d = describe_argv; *d; d++) {
+		struct child_process cp = CHILD_PROCESS_INIT;
+		prepare_submodule_repo_env(&cp.env_array);
+		cp.dir = sub_path;
+		cp.git_cmd = 1;
+		cp.no_stderr = 1;
+
+		argv_array_push(&cp.args, "describe");
+		argv_array_pushv(&cp.args, *d);
+		argv_array_push(&cp.args, object_id);
+
+		if (!capture_command(&cp, &sb, 0) && sb.len) {
+			strbuf_strip_suffix(&sb, "\n");
+			return strbuf_detach(&sb, NULL);
+		}
+
+	}
+
+	strbuf_release(&sb);
+	return NULL;
+}
+
+static int print_name_rev(int argc, const char **argv, const char *prefix)
+{
+	char *namerev;
+	if (argc != 3)
+		die("print-name-rev only accepts two arguments: <path> <sha1>");
+
+	namerev = get_name_rev(argv[1], argv[2]);
+	if (namerev && namerev[0])
+		printf(" (%s)", namerev);
+	printf("\n");
+
+	return 0;
+}
+
 struct module_list {
 	const struct cache_entry **entries;
 	int alloc, nr;
@@ -1242,6 +1304,7 @@ static struct cmd_struct commands[] = {
 	{"relative-path", resolve_relative_path, 0},
 	{"resolve-relative-url", resolve_relative_url, 0},
 	{"resolve-relative-url-test", resolve_relative_url_test, 0},
+	{"print-name-rev", print_name_rev, 0},
 	{"init", module_init, SUPPORT_SUPER_PREFIX},
 	{"remote-branch", resolve_remote_submodule_branch, 0},
 	{"push-check", push_check, 0},
diff --git a/git-submodule.sh b/git-submodule.sh
index e131760ee..e988167e0 100755
--- a/git-submodule.sh
+++ b/git-submodule.sh
@@ -759,18 +759,6 @@ cmd_update()
 	}
 }
 
-set_name_rev () {
-	revname=$( (
-		sanitize_submodule_env
-		cd "$1" && {
-			git describe "$2" 2>/dev/null ||
-			git describe --tags "$2" 2>/dev/null ||
-			git describe --contains "$2" 2>/dev/null ||
-			git describe --all --always "$2"
-		}
-	) )
-	test -z "$revname" || revname=" ($revname)"
-}
 #
 # Show commit summary for submodules in index or working tree
 #
@@ -1042,14 +1030,14 @@ cmd_status()
 		fi
 		if git diff-files --ignore-submodules=dirty --quiet -- "$sm_path"
 		then
-			set_name_rev "$sm_path" "$sha1"
+			revname=$(git submodule--helper print-name-rev "$sm_path" "$sha1")
 			say " $sha1 $displaypath$revname"
 		else
 			if test -z "$cached"
 			then
 				sha1=$(sanitize_submodule_env; cd "$sm_path" && git rev-parse --verify HEAD)
 			fi
-			set_name_rev "$sm_path" "$sha1"
+			revname=$(git submodule--helper print-name-rev "$sm_path" "$sha1")
 			say "+$sha1 $displaypath$revname"
 		fi
 
-- 
2.13.0

[GSoC][PATCH 4/5 v4] submodule: port submodule subcommand 'status' from shell to C

[Prathamesh Chavan]

This aims to make git-submodule 'status' a built-in. Hence, the function
cmd_status() is ported from shell to C. This is done by introducing
three functions: module_status(), submodule_status() and print_status().

The function module_status() acts as the front-end of the subcommand.
It parses subcommand's options and then calls the function
module_list_compute() for computing the list of submodules. Then
this functions calls for_each_submodule_list() looping through the
list obtained.

Then for_each_submodule_list() calls submodule_status() for each of the
submodule in its list. The function submodule_status() is responsible
for generating the status each submodule it is called for, and
then calls print_status().

Finally, the function print_status() handles the printing of submodule's
status.

Mentored-by: Christian Couder <christian.couder@gmail.com>
Mentored-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Prathamesh Chavan <pc44800@gmail.com>
---
In this new version of patch:

Instead of using cmd_diff_files(), the process is optimized
by using ce_match_stat().

Also, the child_process running the command 'rev-parse --verify HEAD'
is removed for optimization reasons, and instead head_ref_submodule()
is used with callback function handle_submodule_head_ref().

The series differs from the complete weekly-update series as these patches
have been reviewed with mentors as well as on mailing list more no. of
times then the rest patches from the complete series, and hence
IMO, are ready for getting included. If not so, I would like to have
suggestions for improvising it.

The patches pass the complete test suite.

 builtin/submodule--helper.c | 146 ++++++++++++++++++++++++++++++++++++++++++++
 git-submodule.sh            |  49 +--------------
 2 files changed, 147 insertions(+), 48 deletions(-)

diff --git a/builtin/submodule--helper.c b/builtin/submodule--helper.c
index 80f744407..9c1630495 100644
--- a/builtin/submodule--helper.c
+++ b/builtin/submodule--helper.c
@@ -560,6 +560,151 @@ static int module_init(int argc, const char **argv, const char *prefix)
 	return 0;
 }
 
+struct status_cb {
+	const char *prefix;
+	unsigned int quiet: 1;
+	unsigned int recursive: 1;
+	unsigned int cached: 1;
+};
+#define STATUS_CB_INIT { NULL, 0, 0, 0 }
+
+static void print_status(struct status_cb *info, char state, const char *path,
+			 char *sub_sha1, char *displaypath)
+{
+	if (info->quiet)
+		return;
+
+	printf("%c%s %s", state, sub_sha1, displaypath);
+
+	if (state == ' ' || state == '+') {
+		struct argv_array name_rev_args = ARGV_ARRAY_INIT;
+
+		argv_array_pushl(&name_rev_args, "print-name-rev",
+				 path, sub_sha1, NULL);
+		print_name_rev(name_rev_args.argc, name_rev_args.argv,
+			       info->prefix);
+	} else {
+		printf("\n");
+	}
+}
+
+static int handle_submodule_head_ref(const char *refname,
+				     const struct object_id *oid, int flags,
+				     void *cb_data)
+{
+	struct strbuf *output = cb_data;
+	if (oid)
+		strbuf_addstr(output, oid_to_hex(oid));
+	return 0;
+}
+
+static void status_submodule(const struct cache_entry *list_item, void *cb_data)
+{
+	struct status_cb *info = cb_data;
+	char *sub_sha1 = xstrdup(oid_to_hex(&list_item->oid));
+	char *displaypath;
+	struct stat st;
+
+	if (!submodule_from_path(null_sha1, list_item->name))
+		die(_("no submodule mapping found in .gitmodules for path '%s'"),
+		      list_item->name);
+
+	displaypath = get_submodule_displaypath(list_item->name, info->prefix);
+
+	if (list_item->ce_flags) {
+		print_status(info, 'U', list_item->name,
+			     sha1_to_hex(null_sha1), displaypath);
+		goto cleanup;
+	}
+
+	if (!is_submodule_active(the_repository, list_item->name)) {
+		print_status(info, '-', list_item->name, sub_sha1, displaypath);
+		goto cleanup;
+	}
+
+	if (!lstat(list_item->name, &st) && !ce_match_stat(list_item, &st, 0)) {
+		print_status(info, ' ', list_item->name, sub_sha1, displaypath);
+	} else {
+		if (!info->cached) {
+			struct strbuf sb = STRBUF_INIT;
+			if (head_ref_submodule(list_item->name,
+					       handle_submodule_head_ref, &sb))
+				die(_("could not resolve HEAD ref inside the"
+				      "submodule '%s'"), list_item->name);
+			print_status(info, '+', list_item->name, sb.buf,
+				     displaypath);
+			strbuf_release(&sb);
+		} else {
+			print_status(info, '+', list_item->name, sub_sha1,
+				     displaypath);
+		}
+	}
+
+	if (info->recursive) {
+		struct child_process cpr = CHILD_PROCESS_INIT;
+
+		cpr.git_cmd = 1;
+		cpr.dir = list_item->name;
+		prepare_submodule_repo_env(&cpr.env_array);
+
+		argv_array_pushl(&cpr.args, "--super-prefix", displaypath,
+				 "submodule--helper", "status", "--recursive",
+				 NULL);
+
+		if (info->cached)
+			argv_array_push(&cpr.args, "--cached");
+
+		if (info->quiet)
+			argv_array_push(&cpr.args, "--quiet");
+
+		if (run_command(&cpr))
+			die(_("failed to recurse into submodule '%s'"),
+			      list_item->name);
+	}
+
+cleanup:
+	free(displaypath);
+	free(sub_sha1);
+}
+
+static int module_status(int argc, const char **argv, const char *prefix)
+{
+	struct status_cb info = STATUS_CB_INIT;
+	struct pathspec pathspec;
+	struct module_list list = MODULE_LIST_INIT;
+	int quiet = 0;
+	int cached = 0;
+	int recursive = 0;
+
+	struct option module_status_options[] = {
+		OPT__QUIET(&quiet, N_("Suppress submodule status output")),
+		OPT_BOOL(0, "cached", &cached, N_("Use commit stored in the index instead of the one stored in the submodule HEAD")),
+		OPT_BOOL(0, "recursive", &recursive, N_("Recurse into nested submodules")),
+		OPT_END()
+	};
+
+	const char *const git_submodule_helper_usage[] = {
+		N_("git submodule status [--quiet] [--cached] [--recursive] [<path>]"),
+		NULL
+	};
+
+	argc = parse_options(argc, argv, prefix, module_status_options,
+			     git_submodule_helper_usage, 0);
+
+	if (module_list_compute(argc, argv, prefix, &pathspec, &list) < 0)
+		return 1;
+
+	info.prefix = prefix;
+	info.quiet = !!quiet;
+	info.recursive = !!recursive;
+	info.cached = !!cached;
+
+	gitmodules_config();
+	for_each_submodule_list(list, status_submodule, &info);
+
+	return 0;
+}
+
 static int module_name(int argc, const char **argv, const char *prefix)
 {
 	const struct submodule *sub;
@@ -1306,6 +1451,7 @@ static struct cmd_struct commands[] = {
 	{"resolve-relative-url-test", resolve_relative_url_test, 0},
 	{"print-name-rev", print_name_rev, 0},
 	{"init", module_init, SUPPORT_SUPER_PREFIX},
+	{"status", module_status, SUPPORT_SUPER_PREFIX},
 	{"remote-branch", resolve_remote_submodule_branch, 0},
 	{"push-check", push_check, 0},
 	{"absorb-git-dirs", absorb_git_dirs, SUPPORT_SUPER_PREFIX},
diff --git a/git-submodule.sh b/git-submodule.sh
index e988167e0..51b057d82 100755
--- a/git-submodule.sh
+++ b/git-submodule.sh
@@ -1005,54 +1005,7 @@ cmd_status()
 		shift
 	done
 
-	{
-		git submodule--helper list --prefix "$wt_prefix" "$@" ||
-		echo "#unmatched" $?
-	} |
-	while read -r mode sha1 stage sm_path
-	do
-		die_if_unmatched "$mode" "$sha1"
-		name=$(git submodule--helper name "$sm_path") || exit
-		displaypath=$(git submodule--helper relative-path "$prefix$sm_path" "$wt_prefix")
-		if test "$stage" = U
-		then
-			say "U$sha1 $displaypath"
-			continue
-		fi
-		if ! git submodule--helper is-active "$sm_path" ||
-		{
-			! test -d "$sm_path"/.git &&
-			! test -f "$sm_path"/.git
-		}
-		then
-			say "-$sha1 $displaypath"
-			continue;
-		fi
-		if git diff-files --ignore-submodules=dirty --quiet -- "$sm_path"
-		then
-			revname=$(git submodule--helper print-name-rev "$sm_path" "$sha1")
-			say " $sha1 $displaypath$revname"
-		else
-			if test -z "$cached"
-			then
-				sha1=$(sanitize_submodule_env; cd "$sm_path" && git rev-parse --verify HEAD)
-			fi
-			revname=$(git submodule--helper print-name-rev "$sm_path" "$sha1")
-			say "+$sha1 $displaypath$revname"
-		fi
-
-		if test -n "$recursive"
-		then
-			(
-				prefix="$displaypath/"
-				sanitize_submodule_env
-				wt_prefix=
-				cd "$sm_path" &&
-				eval cmd_status
-			) ||
-			die "$(eval_gettext "Failed to recurse into submodule path '\$sm_path'")"
-		fi
-	done
+	git ${wt_prefix:+-C "$wt_prefix"} ${prefix:+--super-prefix "$prefix"} submodule--helper status ${GIT_QUIET:+--quiet} ${cached:+--cached} ${recursive:+--recursive} "$@"
 }
 #
 # Sync remote urls for submodules
-- 
2.13.0

Re: [GSoC][PATCH 4/5 v4] submodule: port submodule subcommand 'status' from shell to C

[Stefan Beller]

On Thu, Jul 13, 2017 at 1:05 PM, Prathamesh Chavan <pc44800@gmail.com> wrote:
> This aims to make git-submodule 'status' a built-in. Hence, the function
> cmd_status() is ported from shell to C. This is done by introducing
> three functions: module_status(), submodule_status() and print_status().
>
> The function module_status() acts as the front-end of the subcommand.
> It parses subcommand's options and then calls the function
> module_list_compute() for computing the list of submodules. Then
> this functions calls for_each_submodule_list() looping through the
> list obtained.
>
> Then for_each_submodule_list() calls submodule_status() for each of the
> submodule in its list. The function submodule_status() is responsible
> for generating the status each submodule it is called for, and
> then calls print_status().
>
> Finally, the function print_status() handles the printing of submodule's
> status.
>
> Mentored-by: Christian Couder <christian.couder@gmail.com>
> Mentored-by: Stefan Beller <sbeller@google.com>
> Signed-off-by: Prathamesh Chavan <pc44800@gmail.com>
> ---
> In this new version of patch:
>
> Instead of using cmd_diff_files(), the process is optimized
> by using ce_match_stat().

Apart from this I have reviewed the patch and found it a faithful
conversion.

I am not an expert in the diff area  and wonder how
the cmd_diff_files functionality is achieved with just a stat call
and then comparing it to  ce_match_stat. 'Using "dirty" ignores
all changes to the work tree of submodules, only changes to the
commits stored in the superproject are shown.' So I'd have
expected ce->oid to be compared (is there an index entry differing,
i.e. more than one stage?)


> Also, the child_process running the command 'rev-parse --verify HEAD'
> is removed for optimization reasons, and instead head_ref_submodule()
> is used with callback function handle_submodule_head_ref().

Cool.

[GSoC][PATCH 5/5 v4] submodule: port submodule subcommand 'sync' from shell to C

[Prathamesh Chavan]

Port the submodule subcommand 'sync' from shell to C using the same
mechanism as that used for porting submodule subcommand 'status'.
Hence, here the function cmd_sync() is ported from shell to C.
This is done by introducing three functions: module_sync(),
sync_submodule() and print_default_remote().

The function print_default_remote() is introduced for getting
the default remote as stdout.

Mentored-by: Christian Couder <christian.couder@gmail.com>
Mentored-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Prathamesh Chavan <pc44800@gmail.com>
---
 builtin/submodule--helper.c | 179 ++++++++++++++++++++++++++++++++++++++++++++
 git-submodule.sh            |  56 +-------------
 2 files changed, 180 insertions(+), 55 deletions(-)

diff --git a/builtin/submodule--helper.c b/builtin/submodule--helper.c
index 9c1630495..da91c489b 100644
--- a/builtin/submodule--helper.c
+++ b/builtin/submodule--helper.c
@@ -44,6 +44,20 @@ static char *get_default_remote(void)
 	return ret;
 }
 
+static int print_default_remote(int argc, const char **argv, const char *prefix)
+{
+	const char *remote;
+
+	if (argc != 1)
+		die(_("submodule--helper print-default-remote takes no arguments"));
+
+	remote = get_default_remote();
+	if (remote)
+		puts(remote);
+
+	return 0;
+}
+
 static int starts_with_dot_slash(const char *str)
 {
 	return str[0] == '.' && is_dir_sep(str[1]);
@@ -379,6 +393,25 @@ static void module_list_active(struct module_list *list)
 	*list = active_modules;
 }
 
+static char *get_up_path(const char *path)
+{
+	int i;
+	struct strbuf sb = STRBUF_INIT;
+
+	for (i = count_slashes(path); i; i--)
+		strbuf_addstr(&sb, "../");
+
+	/*
+	 * Check if 'path' ends with slash or not
+	 * for having the same output for dir/sub_dir
+	 * and dir/sub_dir/
+	 */
+	if (!is_dir_sep(path[strlen(path) - 1]))
+		strbuf_addstr(&sb, "../");
+
+	return strbuf_detach(&sb, NULL);
+}
+
 static int module_list(int argc, const char **argv, const char *prefix)
 {
 	int i;
@@ -724,6 +757,150 @@ static int module_name(int argc, const char **argv, const char *prefix)
 	return 0;
 }
 
+struct sync_cb {
+	const char *prefix;
+	unsigned int quiet: 1;
+	unsigned int recursive: 1;
+};
+#define SYNC_CB_INIT { NULL, 0, 0 }
+
+static void sync_submodule(const struct cache_entry *list_item, void *cb_data)
+{
+	struct sync_cb *info = cb_data;
+	const struct submodule *sub;
+	char *sub_key, *remote_key;
+	char *sub_origin_url, *super_config_url, *displaypath;
+	struct strbuf sb = STRBUF_INIT;
+	struct child_process cp = CHILD_PROCESS_INIT;
+
+	if (!is_submodule_active(the_repository, list_item->name))
+		return;
+
+	sub = submodule_from_path(null_sha1, list_item->name);
+
+	if (!sub || !sub->url)
+		die(_("no url found for submodule path '%s' in .gitmodules"),
+		      list_item->name);
+
+	if (starts_with_dot_dot_slash(sub->url) || starts_with_dot_slash(sub->url)) {
+		char *remote_url, *up_path;
+		char *remote = get_default_remote();
+		char *remote_key = xstrfmt("remote.%s.url", remote);
+
+		if (git_config_get_string(remote_key, &remote_url))
+			remote_url = xgetcwd();
+
+		up_path = get_up_path(list_item->name);
+		sub_origin_url = relative_url(remote_url, sub->url, up_path);
+		super_config_url = relative_url(remote_url, sub->url, NULL);
+
+		free(remote);
+		free(remote_key);
+		free(up_path);
+		free(remote_url);
+	} else {
+		sub_origin_url = xstrdup(sub->url);
+		super_config_url = xstrdup(sub->url);
+	}
+
+	displaypath = get_submodule_displaypath(list_item->name, info->prefix);
+
+	if (!info->quiet)
+		printf(_("Synchronizing submodule url for '%s'\n"),
+			 displaypath);
+
+	sub_key = xstrfmt("submodule.%s.url", sub->name);
+	if (git_config_set_gently(sub_key, super_config_url))
+		die(_("failed to register url for submodule path '%s'"),
+		      displaypath);
+
+	if (!is_submodule_populated_gently(list_item->name, NULL))
+		goto cleanup;
+
+	prepare_submodule_repo_env(&cp.env_array);
+	cp.git_cmd = 1;
+	cp.dir = list_item->name;
+	argv_array_pushl(&cp.args, "submodule--helper",
+			 "print-default-remote", NULL);
+	if (capture_command(&cp, &sb, 0))
+		die(_("failed to get the default remote for submodule '%s'"),
+		      list_item->name);
+
+	strbuf_strip_suffix(&sb, "\n");
+	remote_key = xstrfmt("remote.%s.url", sb.buf);
+	strbuf_release(&sb);
+
+	child_process_init(&cp);
+	prepare_submodule_repo_env(&cp.env_array);
+	cp.git_cmd = 1;
+	cp.dir = list_item->name;
+	argv_array_pushl(&cp.args, "config", remote_key, sub_origin_url, NULL);
+	if (run_command(&cp))
+		die(_("failed to update remote for submodule '%s'"),
+		      list_item->name);
+
+	if (info->recursive) {
+		struct child_process cpr = CHILD_PROCESS_INIT;
+
+		cpr.git_cmd = 1;
+		cpr.dir = list_item->name;
+		prepare_submodule_repo_env(&cpr.env_array);
+
+		argv_array_pushl(&cpr.args, "--super-prefix", displaypath,
+				 "submodule--helper", "sync", "--recursive",
+				 NULL);
+
+		if (info->quiet)
+			argv_array_push(&cpr.args, "--quiet");
+
+		if (run_command(&cpr))
+			die(_("failed to recurse into submodule '%s'"),
+			      list_item->name);
+	}
+
+cleanup:
+	free(sub_key);
+	free(super_config_url);
+	free(displaypath);
+	free(sub_origin_url);
+}
+
+static int module_sync(int argc, const char **argv, const char *prefix)
+{
+	struct sync_cb info = SYNC_CB_INIT;
+	struct pathspec pathspec;
+	struct module_list list = MODULE_LIST_INIT;
+	int quiet = 0;
+	int recursive = 0;
+
+	struct option module_sync_options[] = {
+		OPT__QUIET(&quiet, N_("Suppress output of synchronizing submodule url")),
+		OPT_BOOL(0, "recursive", &recursive,
+			N_("Recurse into nested submodules")),
+		OPT_END()
+	};
+
+	const char *const git_submodule_helper_usage[] = {
+		N_("git submodule--helper sync [--quiet] [--recursive] [<path>]"),
+		NULL
+	};
+
+	argc = parse_options(argc, argv, prefix, module_sync_options,
+			     git_submodule_helper_usage, 0);
+
+	if (module_list_compute(argc, argv, prefix, &pathspec, &list) < 0)
+		return 1;
+
+	info.prefix = prefix;
+	info.quiet = !!quiet;
+	info.recursive = !!recursive;
+
+	gitmodules_config();
+	for_each_submodule_list(list, sync_submodule, &info);
+
+	return 0;
+}
+
 static int clone_submodule(const char *path, const char *gitdir, const char *url,
 			   const char *depth, struct string_list *reference,
 			   int quiet, int progress)
@@ -1452,6 +1629,8 @@ static struct cmd_struct commands[] = {
 	{"print-name-rev", print_name_rev, 0},
 	{"init", module_init, SUPPORT_SUPER_PREFIX},
 	{"status", module_status, SUPPORT_SUPER_PREFIX},
+	{"print-default-remote", print_default_remote, 0},
+	{"sync", module_sync, SUPPORT_SUPER_PREFIX},
 	{"remote-branch", resolve_remote_submodule_branch, 0},
 	{"push-check", push_check, 0},
 	{"absorb-git-dirs", absorb_git_dirs, SUPPORT_SUPER_PREFIX},
diff --git a/git-submodule.sh b/git-submodule.sh
index 51b057d82..6bfc5e17d 100755
--- a/git-submodule.sh
+++ b/git-submodule.sh
@@ -1037,63 +1037,9 @@ cmd_sync()
 			;;
 		esac
 	done
-	cd_to_toplevel
-	{
-		git submodule--helper list --prefix "$wt_prefix" "$@" ||
-		echo "#unmatched" $?
-	} |
-	while read -r mode sha1 stage sm_path
-	do
-		die_if_unmatched "$mode" "$sha1"
-
-		# skip inactive submodules
-		if ! git submodule--helper is-active "$sm_path"
-		then
-			continue
-		fi
-
-		name=$(git submodule--helper name "$sm_path")
-		url=$(git config -f .gitmodules --get submodule."$name".url)
-
-		# Possibly a url relative to parent
-		case "$url" in
-		./*|../*)
-			# rewrite foo/bar as ../.. to find path from
-			# submodule work tree to superproject work tree
-			up_path="$(printf '%s\n' "$sm_path" | sed "s/[^/][^/]*/../g")" &&
-			# guarantee a trailing /
-			up_path=${up_path%/}/ &&
-			# path from submodule work tree to submodule origin repo
-			sub_origin_url=$(git submodule--helper resolve-relative-url "$url" "$up_path") &&
-			# path from superproject work tree to submodule origin repo
-			super_config_url=$(git submodule--helper resolve-relative-url "$url") || exit
-			;;
-		*)
-			sub_origin_url="$url"
-			super_config_url="$url"
-			;;
-		esac
 
-		displaypath=$(git submodule--helper relative-path "$prefix$sm_path" "$wt_prefix")
-		say "$(eval_gettext "Synchronizing submodule url for '\$displaypath'")"
-		git config submodule."$name".url "$super_config_url"
-
-		if test -e "$sm_path"/.git
-		then
-		(
-			sanitize_submodule_env
-			cd "$sm_path"
-			remote=$(get_default_remote)
-			git config remote."$remote".url "$sub_origin_url"
+	git ${wt_prefix:+-C "$wt_prefix"} ${prefix:+--super-prefix "$prefix"} submodule--helper sync ${GIT_QUIET:+--quiet} ${recursive:+--recursive} "$@"
 
-			if test -n "$recursive"
-			then
-				prefix="$prefix$sm_path/"
-				eval cmd_sync
-			fi
-		)
-		fi
-	done
 }
 
 cmd_absorbgitdirs()
-- 
2.13.0

[GSOC Update] Week 5

[Pranit Bauva]

================================= SUMMARY ==================================
My public git.git is available here[1]. I regularly keep pushing my work so
anyone interested can track me there. Feel free to participate in the
discussions going on PRs with my mentors. Your comments are valuable.


=============================== INTRODUCTION  ==============================
The purpose of this project is to convert the git-bisect utility which partly
exists in the form of shell scripts to C code so as to make it more portable.
I plan to do this by converting each function to C and then calling it from
git-bisect.sh so as to use the existing test suite to test the function which
is converted.

Mentors:
Christian Couder <chriscool@tuxfamily.org>
Lars Schneider <larsxschneider@gmail.com>


================================== Updates =================================
Things which were done in this week:

 * bisect_clean_state() function is converted and I have fixed the
   segmentation fault. I am now polishing the patch with the help of my
   mentors and will soon send it to the mailing list. The seg fault occurred
   because I was deleting the refs in the for_each_ref_in() iteration. On
   sending the RFC[2], Michael Haggerty pointed out the fact that deleting refs
   causes some malfunction with the ref cache and thus triggering the seg
   fault.

 * I also converted bisect_write() function and currently I am polishing it
   with the help of my mentors and will send it to the mailing list. You can
   find the whole branch here[3].

 * As a preparatory patch for bisect_write() I also introduced a function
   file_size() which will get the file size without actually opening the
   file.

 * I also converted is_expected_rev() and check_expected_revs() and also fixed
   the segmentation fault. I am now polishing the patch with the help of my
   mentors and will soon send it to the mailing list. You can find the branch
   here[4].

 * My v2[5] on a cleanup patch to use the function macro GIT_PATH_FUNC is
   yet to receive comments.

 * I have also converted bisect_head()[6] but that would be sent to the mailing
   list along with bisect_state().

================================= NEXT STEPS ================================
Things which would be done in the coming week:

 * Convert the function bisect_write(). I plan to convert this function and
   add it as a subcommand.

 * Convert get_terms() and add the variables TERM_GOOD and TERM_BAD in a struct
   in the global state.

 * Convert bisect_voc()

 * Convert bisect_next_check()

[1]: https://github.com/pranitbauva1997/git
[2]: http://thread.gmane.org/gmane.comp.version-control.git/295917
[3]: https://github.com/pranitbauva1997/git/pull/13
[4]: https://github.com/pranitbauva1997/git/pull/10
[5]: http://thread.gmane.org/gmane.comp.version-control.git/295524
[6]: https://github.com/pranitbauva1997/git/pull/11


Regards,
Pranit Bauva

[GSOC Update] Week 6

[Pranit Bauva]

================================= SUMMARY ==================================
My public git.git is available here[1]. I regularly keep pushing my work so
anyone interested can track me there. Feel free to participate in the
discussions going on PRs with my mentors. Your comments are valuable.


=============================== INTRODUCTION  ==============================
The purpose of this project is to convert the git-bisect utility which partly
exists in the form of shell scripts to C code so as to make it more portable.
I plan to do this by converting each function to C and then calling it from
git-bisect.sh so as to use the existing test suite to test the function which
is converted.

Mentors:
Christian Couder <chriscool@tuxfamily.org>
Lars Schneider <larsxschneider@gmail.com>


================================== Updates =================================
Things which were done in this week:

 * bisect_clean_state() function is converted and sent out to the mailing
   list which received some useful comments from Eric Sunshine and the
   updated version can be found on bisect-reset branch[3].

 * I also converted bisect_reset() function and also introduced a file_size()
   method which received some useful comments from Eric Sunshine and Torsten
   Bogershausen. You can find the whole branch here[3].

 * I have also converted bisect_write() and will send it to the mailing list
   soon. The branch can be found here[4].

 * I also converted is_expected_rev() and check_expected_revs(). I sent
   it to the mailing list which collected some useful reviews from Eric
   Sunshine. I have updated according to the reviews. I need to confirm it
   once before I send it out on the mailing list. You can find the branch
   here[3].

 * My v2[5] on a cleanup patch to use the function macro GIT_PATH_FUNC is
   yet queued on the pu branch.

================================= NEXT STEPS ================================
Things which would be done in the coming week:

 * check_and_set_terms(): This function uses the two global variables in the
   script namely TERM_GOOD TERM_BAD. I have decided to pass then as arguments.

 * get_terms(): This will also introduce a struct to store global variables
   namely TERM_GOOD and TERM_BAD.

 * bisect_terms().

 * bisect_next_check().

[1]: https://github.com/pranitbauva1997/git
[3]: https://github.com/pranitbauva1997/git/pull/13
[4]: https://github.com/pranitbauva1997/git/pull/14
[5]: http://thread.gmane.org/gmane.comp.version-control.git/295524


Regards,
Pranit Bauva