Merge branch 'bw/recurse-submodules-relative-fix'

A few commands that recently learned the "--recurse-submodule"
option misbehaved when started from a subdirectory of the
superproject.

* bw/recurse-submodules-relative-fix:
  ls-files: fix bug when recursing with relative pathspec
  ls-files: fix typo in variable name
  grep: fix bug when recursing with relative pathspec
  setup: allow for prefix to be passed to git commands
  grep: fix help text typo
diff --git a/builtin/grep.c b/builtin/grep.c
index 3f3efa9..65070c5 100644
--- a/builtin/grep.c
+++ b/builtin/grep.c
@@ -310,10 +310,7 @@ static int grep_oid(struct grep_opt *opt, const struct object_id *oid,
 {
 	struct strbuf pathbuf = STRBUF_INIT;
 
-	if (opt->relative && opt->prefix_length) {
-		quote_path_relative(filename + tree_name_len, opt->prefix, &pathbuf);
-		strbuf_insert(&pathbuf, 0, filename, tree_name_len);
-	} else if (super_prefix) {
+	if (super_prefix) {
 		strbuf_add(&pathbuf, filename, tree_name_len);
 		strbuf_addstr(&pathbuf, super_prefix);
 		strbuf_addstr(&pathbuf, filename + tree_name_len);
@@ -321,6 +318,13 @@ static int grep_oid(struct grep_opt *opt, const struct object_id *oid,
 		strbuf_addstr(&pathbuf, filename);
 	}
 
+	if (opt->relative && opt->prefix_length) {
+		char *name = strbuf_detach(&pathbuf, NULL);
+		quote_path_relative(name + tree_name_len, opt->prefix, &pathbuf);
+		strbuf_insert(&pathbuf, 0, name, tree_name_len);
+		free(name);
+	}
+
 #ifndef NO_PTHREADS
 	if (num_threads) {
 		add_work(opt, GREP_SOURCE_SHA1, pathbuf.buf, path, oid);
@@ -345,12 +349,14 @@ static int grep_file(struct grep_opt *opt, const char *filename)
 {
 	struct strbuf buf = STRBUF_INIT;
 
+	if (super_prefix)
+		strbuf_addstr(&buf, super_prefix);
+	strbuf_addstr(&buf, filename);
+
 	if (opt->relative && opt->prefix_length) {
-		quote_path_relative(filename, opt->prefix, &buf);
-	} else {
-		if (super_prefix)
-			strbuf_addstr(&buf, super_prefix);
-		strbuf_addstr(&buf, filename);
+		char *name = strbuf_detach(&buf, NULL);
+		quote_path_relative(name, opt->prefix, &buf);
+		free(name);
 	}
 
 #ifndef NO_PTHREADS
@@ -399,13 +405,12 @@ static void run_pager(struct grep_opt *opt, const char *prefix)
 }
 
 static void compile_submodule_options(const struct grep_opt *opt,
-				      const struct pathspec *pathspec,
+				      const char **argv,
 				      int cached, int untracked,
 				      int opt_exclude, int use_index,
 				      int pattern_type_arg)
 {
 	struct grep_pat *pattern;
-	int i;
 
 	if (recurse_submodules)
 		argv_array_push(&submodule_options, "--recurse-submodules");
@@ -523,9 +528,8 @@ static void compile_submodule_options(const struct grep_opt *opt,
 
 	/* Add Pathspecs */
 	argv_array_push(&submodule_options, "--");
-	for (i = 0; i < pathspec->nr; i++)
-		argv_array_push(&submodule_options,
-				pathspec->items[i].original);
+	for (; *argv; argv++)
+		argv_array_push(&submodule_options, *argv);
 }
 
 /*
@@ -549,6 +553,11 @@ static int grep_submodule_launch(struct grep_opt *opt,
 	prepare_submodule_repo_env(&cp.env_array);
 	argv_array_push(&cp.env_array, GIT_DIR_ENVIRONMENT);
 
+	if (opt->relative && opt->prefix_length)
+		argv_array_pushf(&cp.env_array, "%s=%s",
+				 GIT_TOPLEVEL_PREFIX_ENVIRONMENT,
+				 opt->prefix);
+
 	/* Add super prefix */
 	argv_array_pushf(&cp.args, "--super-prefix=%s%s/",
 			 super_prefix ? super_prefix : "",
@@ -976,7 +985,7 @@ int cmd_grep(int argc, const char **argv, const char *prefix)
 		OPT_SET_INT(0, "exclude-standard", &opt_exclude,
 			    N_("ignore files specified via '.gitignore'"), 1),
 		OPT_BOOL(0, "recurse-submodules", &recurse_submodules,
-			 N_("recursivley search in each submodule")),
+			 N_("recursively search in each submodule")),
 		OPT_STRING(0, "parent-basename", &parent_basename,
 			   N_("basename"),
 			   N_("prepend parent project's basename to output")),
@@ -1233,7 +1242,7 @@ int cmd_grep(int argc, const char **argv, const char *prefix)
 
 	if (recurse_submodules) {
 		gitmodules_config();
-		compile_submodule_options(&opt, &pathspec, cached, untracked,
+		compile_submodule_options(&opt, argv + i, cached, untracked,
 					  opt_exclude, use_index,
 					  pattern_type_arg);
 	}
diff --git a/builtin/ls-files.c b/builtin/ls-files.c
index 1c0f057..d449e46 100644
--- a/builtin/ls-files.c
+++ b/builtin/ls-files.c
@@ -30,7 +30,7 @@ static int line_terminator = '\n';
 static int debug_mode;
 static int show_eol;
 static int recurse_submodules;
-static struct argv_array submodules_options = ARGV_ARRAY_INIT;
+static struct argv_array submodule_options = ARGV_ARRAY_INIT;
 
 static const char *prefix;
 static const char *super_prefix;
@@ -172,20 +172,27 @@ static void show_killed_files(struct dir_struct *dir)
 /*
  * Compile an argv_array with all of the options supported by --recurse_submodules
  */
-static void compile_submodule_options(const struct dir_struct *dir, int show_tag)
+static void compile_submodule_options(const char **argv,
+				      const struct dir_struct *dir,
+				      int show_tag)
 {
 	if (line_terminator == '\0')
-		argv_array_push(&submodules_options, "-z");
+		argv_array_push(&submodule_options, "-z");
 	if (show_tag)
-		argv_array_push(&submodules_options, "-t");
+		argv_array_push(&submodule_options, "-t");
 	if (show_valid_bit)
-		argv_array_push(&submodules_options, "-v");
+		argv_array_push(&submodule_options, "-v");
 	if (show_cached)
-		argv_array_push(&submodules_options, "--cached");
+		argv_array_push(&submodule_options, "--cached");
 	if (show_eol)
-		argv_array_push(&submodules_options, "--eol");
+		argv_array_push(&submodule_options, "--eol");
 	if (debug_mode)
-		argv_array_push(&submodules_options, "--debug");
+		argv_array_push(&submodule_options, "--debug");
+
+	/* Add Pathspecs */
+	argv_array_push(&submodule_options, "--");
+	for (; *argv; argv++)
+		argv_array_push(&submodule_options, *argv);
 }
 
 /**
@@ -195,8 +202,11 @@ static void show_gitlink(const struct cache_entry *ce)
 {
 	struct child_process cp = CHILD_PROCESS_INIT;
 	int status;
-	int i;
 
+	if (prefix_len)
+		argv_array_pushf(&cp.env_array, "%s=%s",
+				 GIT_TOPLEVEL_PREFIX_ENVIRONMENT,
+				 prefix);
 	argv_array_pushf(&cp.args, "--super-prefix=%s%s/",
 			 super_prefix ? super_prefix : "",
 			 ce->name);
@@ -204,16 +214,7 @@ static void show_gitlink(const struct cache_entry *ce)
 	argv_array_push(&cp.args, "--recurse-submodules");
 
 	/* add supported options */
-	argv_array_pushv(&cp.args, submodules_options.argv);
-
-	/*
-	 * Pass in the original pathspec args.  The submodule will be
-	 * responsible for prepending the 'submodule_prefix' prior to comparing
-	 * against the pathspec for matches.
-	 */
-	argv_array_push(&cp.args, "--");
-	for (i = 0; i < pathspec.nr; i++)
-		argv_array_push(&cp.args, pathspec.items[i].original);
+	argv_array_pushv(&cp.args, submodule_options.argv);
 
 	cp.git_cmd = 1;
 	cp.dir = ce->name;
@@ -604,7 +605,7 @@ int cmd_ls_files(int argc, const char **argv, const char *cmd_prefix)
 		setup_work_tree();
 
 	if (recurse_submodules)
-		compile_submodule_options(&dir, show_tag);
+		compile_submodule_options(argv, &dir, show_tag);
 
 	if (recurse_submodules &&
 	    (show_stage || show_deleted || show_others || show_unmerged ||
diff --git a/cache.h b/cache.h
index fbdf7a8..5c80782 100644
--- a/cache.h
+++ b/cache.h
@@ -411,6 +411,7 @@ static inline enum object_type object_type(unsigned int mode)
 #define GIT_WORK_TREE_ENVIRONMENT "GIT_WORK_TREE"
 #define GIT_PREFIX_ENVIRONMENT "GIT_PREFIX"
 #define GIT_SUPER_PREFIX_ENVIRONMENT "GIT_INTERNAL_SUPER_PREFIX"
+#define GIT_TOPLEVEL_PREFIX_ENVIRONMENT "GIT_INTERNAL_TOPLEVEL_PREFIX"
 #define DEFAULT_GIT_DIR_ENVIRONMENT ".git"
 #define DB_ENVIRONMENT "GIT_OBJECT_DIRECTORY"
 #define INDEX_ENVIRONMENT "GIT_INDEX_FILE"
diff --git a/git.c b/git.c
index 33f52ac..8ff44f0 100644
--- a/git.c
+++ b/git.c
@@ -361,8 +361,6 @@ static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
 	if (!help && get_super_prefix()) {
 		if (!(p->option & SUPPORT_SUPER_PREFIX))
 			die("%s doesn't support --super-prefix", p->cmd);
-		if (prefix)
-			die("can't use --super-prefix from a subdirectory");
 	}
 
 	if (!help && p->option & NEED_WORK_TREE)
diff --git a/setup.c b/setup.c
index 5c7946d..0309c27 100644
--- a/setup.c
+++ b/setup.c
@@ -987,7 +987,7 @@ const char *setup_git_directory_gently(int *nongit_ok)
 {
 	static struct strbuf cwd = STRBUF_INIT;
 	struct strbuf dir = STRBUF_INIT, gitdir = STRBUF_INIT;
-	const char *prefix;
+	const char *prefix, *env_prefix;
 
 	/*
 	 * We may have read an incomplete configuration before
@@ -1045,6 +1045,10 @@ const char *setup_git_directory_gently(int *nongit_ok)
 		die("BUG: unhandled setup_git_directory_1() result");
 	}
 
+	env_prefix = getenv(GIT_TOPLEVEL_PREFIX_ENVIRONMENT);
+	if (env_prefix)
+		prefix = env_prefix;
+
 	if (prefix)
 		setenv(GIT_PREFIX_ENVIRONMENT, prefix, 1);
 	else
diff --git a/t/t3007-ls-files-recurse-submodules.sh b/t/t3007-ls-files-recurse-submodules.sh
index a542617..4cf6ccf 100755
--- a/t/t3007-ls-files-recurse-submodules.sh
+++ b/t/t3007-ls-files-recurse-submodules.sh
@@ -188,6 +188,45 @@
 	test_cmp expect actual
 '
 
+test_expect_success '--recurse-submodules and relative paths' '
+	# From subdir
+	cat >expect <<-\EOF &&
+	b
+	EOF
+	git -C b ls-files --recurse-submodules >actual &&
+	test_cmp expect actual &&
+
+	# Relative path to top
+	cat >expect <<-\EOF &&
+	../.gitmodules
+	../a
+	b
+	../h.txt
+	../sib/file
+	../sub/file
+	../submodule/.gitmodules
+	../submodule/c
+	../submodule/f.TXT
+	../submodule/g.txt
+	../submodule/subsub/d
+	../submodule/subsub/e.txt
+	EOF
+	git -C b ls-files --recurse-submodules -- .. >actual &&
+	test_cmp expect actual &&
+
+	# Relative path to submodule
+	cat >expect <<-\EOF &&
+	../submodule/.gitmodules
+	../submodule/c
+	../submodule/f.TXT
+	../submodule/g.txt
+	../submodule/subsub/d
+	../submodule/subsub/e.txt
+	EOF
+	git -C b ls-files --recurse-submodules -- ../submodule >actual &&
+	test_cmp expect actual
+'
+
 test_expect_success '--recurse-submodules does not support --error-unmatch' '
 	test_must_fail git ls-files --recurse-submodules --error-unmatch 2>actual &&
 	test_i18ngrep "does not support --error-unmatch" actual
diff --git a/t/t7814-grep-recurse-submodules.sh b/t/t7814-grep-recurse-submodules.sh
index 67247a0..5b6eb3a 100755
--- a/t/t7814-grep-recurse-submodules.sh
+++ b/t/t7814-grep-recurse-submodules.sh
@@ -227,6 +227,81 @@
 	test_cmp expect actual
 '
 
+test_expect_success 'grep using relative path' '
+	test_when_finished "rm -rf parent sub" &&
+	git init sub &&
+	echo "foobar" >sub/file &&
+	git -C sub add file &&
+	git -C sub commit -m "add file" &&
+
+	git init parent &&
+	echo "foobar" >parent/file &&
+	git -C parent add file &&
+	mkdir parent/src &&
+	echo "foobar" >parent/src/file2 &&
+	git -C parent add src/file2 &&
+	git -C parent submodule add ../sub &&
+	git -C parent commit -m "add files and submodule" &&
+
+	# From top works
+	cat >expect <<-\EOF &&
+	file:foobar
+	src/file2:foobar
+	sub/file:foobar
+	EOF
+	git -C parent grep --recurse-submodules -e "foobar" >actual &&
+	test_cmp expect actual &&
+
+	# Relative path to top
+	cat >expect <<-\EOF &&
+	../file:foobar
+	file2:foobar
+	../sub/file:foobar
+	EOF
+	git -C parent/src grep --recurse-submodules -e "foobar" -- .. >actual &&
+	test_cmp expect actual &&
+
+	# Relative path to submodule
+	cat >expect <<-\EOF &&
+	../sub/file:foobar
+	EOF
+	git -C parent/src grep --recurse-submodules -e "foobar" -- ../sub >actual &&
+	test_cmp expect actual
+'
+
+test_expect_success 'grep from a subdir' '
+	test_when_finished "rm -rf parent sub" &&
+	git init sub &&
+	echo "foobar" >sub/file &&
+	git -C sub add file &&
+	git -C sub commit -m "add file" &&
+
+	git init parent &&
+	mkdir parent/src &&
+	echo "foobar" >parent/src/file &&
+	git -C parent add src/file &&
+	git -C parent submodule add ../sub src/sub &&
+	git -C parent submodule add ../sub sub &&
+	git -C parent commit -m "add files and submodules" &&
+
+	# Verify grep from root works
+	cat >expect <<-\EOF &&
+	src/file:foobar
+	src/sub/file:foobar
+	sub/file:foobar
+	EOF
+	git -C parent grep --recurse-submodules -e "foobar" >actual &&
+	test_cmp expect actual &&
+
+	# Verify grep from a subdir works
+	cat >expect <<-\EOF &&
+	file:foobar
+	sub/file:foobar
+	EOF
+	git -C parent/src grep --recurse-submodules -e "foobar" >actual &&
+	test_cmp expect actual
+'
+
 test_incompatible_with_recurse_submodules ()
 {
 	test_expect_success "--recurse-submodules and $1 are incompatible" "