[PATCH jx/clean-interactive] t0060: skip a few relative_path tests on Windows

@@ -190,15 +190,15 @@ test_expect_success SYMLINKS 'real path works on

@@ -12,6 +12,11 @@ norm_path() {
 	"test \"\$(test-path-utils normalize_path_copy '$1')\" = '$2'"
 }
 
+relative_path() {
+	test_expect_success $4 "relative path: $1 $2 => $3" \
+	"test \"\$(test-path-utils relative_path '$1' '$2')\" = '$3'"
+}
+
 # On Windows, we are using MSYS's bash, which mangles the paths.
 # Absolute paths are anchored at the MSYS installation directory,
 # which means that the path / accounts for this many characters:

@@ -183,4 +188,25 @@ test_expect_success SYMLINKS 'real path works on symlinks' '
 	test "$sym" = "$(test-path-utils real_path "$dir2/syml")"
 '
 
+relative_path /a/b/c/	/a/b/		c/
+relative_path /a/b/c/	/a/b		c/
+relative_path /a//b//c/	//a/b//		c/	POSIX
+relative_path /a/b	/a/b		.
+relative_path /a/b/	/a/b		.
+relative_path /a	/a/b		/a	POSIX
+relative_path /		/a/b/		/	POSIX
+relative_path /a/c	/a/b/		/a/c	POSIX
+relative_path /a/c	/a/b		/a/c	POSIX
+relative_path /a/b	"<empty>"	/a/b	POSIX
+relative_path /a/b 	"<null>"	/a/b	POSIX
+relative_path "<empty>"	/a/b		"(empty)"
+relative_path "<empty>"	"<empty>"	"(empty)"
+relative_path "<empty>"	"<null>"	"(empty)"
+relative_path "<null>"	"<empty>"	"(null)"
+relative_path "<null>"	"<null>"	"(null)"
+
+test_expect_failure 'relative path: <null> /a/b => segfault' '
+	test-path-utils relative_path "<null>" "/a/b"
+'
+
 test_done

@@ -28,6 +28,19 @@ static int normalize_ceiling_entry(struct string_list_item *item, void *unused)
 	return 1;
 }
 
+static void normalize_argv_string(const char **var, const char *input)
+{
+	if (!strcmp(input, "<null>"))
+		*var = NULL;
+	else if (!strcmp(input, "<empty>"))
+		*var = "";
+	else
+		*var = input;
+
+	if (*var && (**var == '<' || **var == '('))
+		die("Bad value: %s\n", input);
+}
+
 int main(int argc, char **argv)
 {
 	if (argc == 3 && !strcmp(argv[1], "normalize_path_copy")) {

@@ -103,6 +116,18 @@ int main(int argc, char **argv)
 		return 0;
 	}
 
+	if (argc == 4 && !strcmp(argv[1], "relative_path")) {
+		const char *abs, *base, *rel;
+		normalize_argv_string(&abs, argv[2]);
+		normalize_argv_string(&base, argv[3]);
+		rel = relative_path(abs, base);
+		if (!rel)
+			puts("(null)");
+		else
+			puts(strlen(rel) > 0 ? rel : "(empty)");
+		return 0;
+	}
+
 	fprintf(stderr, "%s: unknown function name: %s\n", argv[0],
 		argv[1] ? argv[1] : "(there was none)");
 	return 1;

@@ -758,7 +758,7 @@ int is_directory(const char *);
 const char *real_path(const char *path);
 const char *real_path_if_valid(const char *path);
 const char *absolute_path(const char *path);
-const char *relative_path(const char *abs, const char *base);
+const char *relative_path(const char *abs, const char *base, struct strbuf *sb);
 int normalize_path_copy(char *dst, const char *src);
 int longest_ancestor_length(const char *path, struct string_list *prefixes);
 char *strip_path_suffix(const char *path, const char *suffix);

@@ -441,42 +441,104 @@ int adjust_shared_perm(const char *path)
 	return 0;
 }
 
-const char *relative_path(const char *abs, const char *base)
+/*
+ * Give relative path for abs to base.
+ *
+ * The strbuf may or may not be used, so do not assume it contains the
+ * returned path.
+ */
+const char *relative_path(const char *abs, const char *base,
+			  struct strbuf *sb)
 {
-	static char buf[PATH_MAX + 1];
-	int i = 0, j = 0;
-
-	if (!base || !base[0])
+	int abs_off, base_off, i, j;
+	int abs_len, base_len;
+
+	abs_len = abs ? strlen(abs) : 0;
+	base_len = base ? strlen(base) : 0;
+	abs_off = 0;
+	base_off = 0;
+	i = 0;
+	j = 0;
+
+	if (!abs_len)
+		return "./";
+	else if (!base_len)
 		return abs;
-	while (base[i]) {
+
+	while (i < base_len && j < abs_len && base[i] == abs[j]) {
 		if (is_dir_sep(base[i])) {
-			if (!is_dir_sep(abs[j]))
-				return abs;
 			while (is_dir_sep(base[i]))
 				i++;
 			while (is_dir_sep(abs[j]))
 				j++;
-			continue;
-		} else if (abs[j] != base[i]) {
+			base_off = i;
+			abs_off = j;
+		} else {
+			i++;
+			j++;
+		}
+	}
+
+	if (
+	    /* base seems like prefix of abs */
+	    i >= base_len &&
+	    /*
+	     * but "/foo" is not a prefix of "/foobar"
+	     * (i.e. base not end with '/')
+	     */
+	    base_off < base_len) {
+		if (j >= abs_len) {
+			/* abs="/a/b", base="/a/b" */
+			abs_off = abs_len;
+		} else if (is_dir_sep(abs[j])) {
+			/* abs="/a/b/c", base="/a/b" */
+			while (is_dir_sep(abs[j]))
+				j++;
+			abs_off = j;
+		} else {
+			/* abs="/a/bbb/c", base="/a/b" */
+			i = base_off;
+		}
+	} else if (
+		   /* abs is short than base (prefix of base) */
+		   j >= abs_len &&
+		   /* abs not end with '/' */
+		   abs_off < abs_len) {
+		if (is_dir_sep(base[i])) {
+			/* abs="/a/b", base="/a/b/c/" */
+			while (is_dir_sep(base[i]))
+				i++;
+			abs_off = abs_len;
+		}
+	}
+	abs += abs_off;
+	abs_len -= abs_off;
+
+	if (i >= base_len) {
+		if (!abs_len)
+			return "./";
+		else
 			return abs;
+	}
+
+	strbuf_reset(sb);
+	strbuf_grow(sb, abs_len);
+
+	while (i < base_len) {
+		if (is_dir_sep(base[i])) {
+			strbuf_addstr(sb, "../");
+			while (is_dir_sep(base[i]))
+				i++;
+			continue;
 		}
 		i++;
-		j++;
 	}
-	if (
-	    /* "/foo" is a prefix of "/foo" */
-	    abs[j] &&
-	    /* "/foo" is not a prefix of "/foobar" */
-	    !is_dir_sep(base[i-1]) && !is_dir_sep(abs[j])
-	   )
-		return abs;
-	while (is_dir_sep(abs[j]))
-		j++;
-	if (!abs[j])
-		strcpy(buf, ".");
-	else
-		strcpy(buf, abs + j);
-	return buf;
+	if (!is_dir_sep(base[base_len - 1]))
+		strbuf_addstr(sb, "../");
+
+	strbuf_addstr(sb, abs);
+
+	return sb->buf;
 }
 
 /*

@@ -360,6 +360,7 @@ int is_inside_work_tree(void)
 
 void setup_work_tree(void)
 {
+	struct strbuf sb = STRBUF_INIT;
 	const char *work_tree, *git_dir;
 	static int initialized = 0;
 

@@ -379,8 +380,10 @@ void setup_work_tree(void)
 	if (getenv(GIT_WORK_TREE_ENVIRONMENT))
 		setenv(GIT_WORK_TREE_ENVIRONMENT, ".", 1);
 
-	set_git_dir(relative_path(git_dir, work_tree));
+	set_git_dir(relative_path(git_dir, work_tree, &sb));
 	initialized = 1;
+
+	strbuf_release(&sb);
 }
 
 static int check_repository_format_gently(const char *gitdir, int *nongit_ok)

@@ -191,22 +191,19 @@ test_expect_success SYMLINKS 'real path works on symlinks' '
 relative_path /a/b/c/	/a/b/		c/
 relative_path /a/b/c/	/a/b		c/
 relative_path /a//b//c/	//a/b//		c/	POSIX
-relative_path /a/b	/a/b		.
-relative_path /a/b/	/a/b		.
-relative_path /a	/a/b		/a	POSIX
-relative_path /		/a/b/		/	POSIX
-relative_path /a/c	/a/b/		/a/c	POSIX
-relative_path /a/c	/a/b		/a/c	POSIX
+relative_path /a/b	/a/b		./
+relative_path /a/b/	/a/b		./
+relative_path /a	/a/b		../
+relative_path /		/a/b/		../../
+relative_path /a/c	/a/b/		../c
+relative_path /a/c	/a/b		../c
 relative_path /a/b	"<empty>"	/a/b	POSIX
 relative_path /a/b 	"<null>"	/a/b	POSIX
-relative_path "<empty>"	/a/b		"(empty)"
-relative_path "<empty>"	"<empty>"	"(empty)"
-relative_path "<empty>"	"<null>"	"(empty)"
-relative_path "<null>"	"<empty>"	"(null)"
-relative_path "<null>"	"<null>"	"(null)"
-
-test_expect_failure 'relative path: <null> /a/b => segfault' '
-	test-path-utils relative_path "<null>" "/a/b"
-'
+relative_path "<empty>"	/a/b		./
+relative_path "<empty>"	"<empty>"	./
+relative_path "<empty>"	"<null>"	./
+relative_path "<null>"	"<empty>"	./
+relative_path "<null>"	"<null>"	./
+relative_path "<null>"	/a/b		./
 
 test_done

@@ -117,14 +117,16 @@ int main(int argc, char **argv)
 	}
 
 	if (argc == 4 && !strcmp(argv[1], "relative_path")) {
+		struct strbuf sb = STRBUF_INIT;
 		const char *abs, *base, *rel;
 		normalize_argv_string(&abs, argv[2]);
 		normalize_argv_string(&base, argv[3]);
-		rel = relative_path(abs, base);
+		rel = relative_path(abs, base, &sb);
 		if (!rel)
 			puts("(null)");
 		else
 			puts(strlen(rel) > 0 ? rel : "(empty)");
+		strbuf_release(&sb);
 		return 0;
 	}
 

@@ -312,75 +312,24 @@ void write_name_quotedpfx(const char *pfx, size_t pfxlen,
 	fputc(terminator, fp);
 }
 
-static const char *path_relative(const char *in, int len,
-				 struct strbuf *sb, const char *prefix,
-				 int prefix_len);
-
 void write_name_quoted_relative(const char *name, size_t len,
 				const char *prefix, size_t prefix_len,
 				FILE *fp, int terminator)
 {
 	struct strbuf sb = STRBUF_INIT;
 
-	name = path_relative(name, len, &sb, prefix, prefix_len);
+	name = relative_path(name, prefix, &sb);
 	write_name_quoted(name, fp, terminator);
 
 	strbuf_release(&sb);
 }
 
-/*
- * Give path as relative to prefix.
- *
- * The strbuf may or may not be used, so do not assume it contains the
- * returned path.
- */
-static const char *path_relative(const char *in, int len,
-				 struct strbuf *sb, const char *prefix,
-				 int prefix_len)
-{
-	int off, i;
-
-	if (len < 0)
-		len = strlen(in);
-	if (prefix_len < 0) {
-		if (prefix)
-			prefix_len = strlen(prefix);
-		else
-			prefix_len = 0;
-	}
-
-	off = 0;
-	i = 0;
-	while (i < prefix_len && i < len && prefix[i] == in[i]) {
-		if (prefix[i] == '/')
-			off = i + 1;
-		i++;
-	}
-	in += off;
-	len -= off;
-
-	if (i >= prefix_len)
-		return in;
-
-	strbuf_reset(sb);
-	strbuf_grow(sb, len);
-
-	while (i < prefix_len) {
-		if (prefix[i] == '/')
-			strbuf_addstr(sb, "../");
-		i++;
-	}
-	strbuf_add(sb, in, len);
-
-	return sb->buf;
-}
-
 /* quote path as relative to the given prefix */
 char *quote_path_relative(const char *in, int len,
 			  struct strbuf *out, const char *prefix)
 {
 	struct strbuf sb = STRBUF_INIT;
-	const char *rel = path_relative(in, len, &sb, prefix, -1);
+	const char *rel = relative_path(in, prefix, &sb);
 	strbuf_reset(out);
 	quote_c_style_counted(rel, strlen(rel), out, NULL, 0);
 	strbuf_release(&sb);

@@ -56,7 +56,7 @@ static int remove_dirs(struct strbuf *path, const char *prefix, int force_flag,
 	if ((force_flag & REMOVE_DIR_KEEP_NESTED_GIT) &&
 			!resolve_gitlink_ref(path->buf, "HEAD", submodule_head)) {
 		if (!quiet) {
-			quote_path_relative(path->buf, strlen(path->buf), &quoted, prefix);
+			quote_path_relative(path->buf, prefix, &quoted);
 			printf(dry_run ?  _(msg_would_skip_git_dir) : _(msg_skip_git_dir),
 					quoted.buf);
 		}

@@ -70,7 +70,7 @@ static int remove_dirs(struct strbuf *path, const char *prefix, int force_flag,
 		/* an empty dir could be removed even if it is unreadble */
 		res = dry_run ? 0 : rmdir(path->buf);
 		if (res) {
-			quote_path_relative(path->buf, strlen(path->buf), &quoted, prefix);
+			quote_path_relative(path->buf, prefix, &quoted);
 			warning(_(msg_warn_remove_failed), quoted.buf);
 			*dir_gone = 0;
 		}

@@ -94,7 +94,7 @@ static int remove_dirs(struct strbuf *path, const char *prefix, int force_flag,
 			if (remove_dirs(path, prefix, force_flag, dry_run, quiet, &gone))
 				ret = 1;
 			if (gone) {
-				quote_path_relative(path->buf, strlen(path->buf), &quoted, prefix);
+				quote_path_relative(path->buf, prefix, &quoted);
 				string_list_append(&dels, quoted.buf);
 			} else
 				*dir_gone = 0;

@@ -102,10 +102,10 @@ static int remove_dirs(struct strbuf *path, const char *prefix, int force_flag,
 		} else {
 			res = dry_run ? 0 : unlink(path->buf);
 			if (!res) {
-				quote_path_relative(path->buf, strlen(path->buf), &quoted, prefix);
+				quote_path_relative(path->buf, prefix, &quoted);
 				string_list_append(&dels, quoted.buf);
 			} else {
-				quote_path_relative(path->buf, strlen(path->buf), &quoted, prefix);
+				quote_path_relative(path->buf, prefix, &quoted);
 				warning(_(msg_warn_remove_failed), quoted.buf);
 				*dir_gone = 0;
 				ret = 1;

@@ -127,7 +127,7 @@ static int remove_dirs(struct strbuf *path, const char *prefix, int force_flag,
 		if (!res)
 			*dir_gone = 1;
 		else {
-			quote_path_relative(path->buf, strlen(path->buf), &quoted, prefix);
+			quote_path_relative(path->buf, prefix, &quoted);
 			warning(_(msg_warn_remove_failed), quoted.buf);
 			*dir_gone = 0;
 			ret = 1;

@@ -262,7 +262,7 @@ int cmd_clean(int argc, const char **argv, const char *prefix)
 				if (remove_dirs(&directory, prefix, rm_flags, dry_run, quiet, &gone))
 					errors++;
 				if (gone && !quiet) {
-					qname = quote_path_relative(directory.buf, directory.len, &buf, prefix);
+					qname = quote_path_relative(directory.buf, prefix, &buf);
 					printf(dry_run ? _(msg_would_remove) : _(msg_remove), qname);
 				}
 			}

@@ -272,11 +272,11 @@ int cmd_clean(int argc, const char **argv, const char *prefix)
 				continue;
 			res = dry_run ? 0 : unlink(ent->name);
 			if (res) {
-				qname = quote_path_relative(ent->name, -1, &buf, prefix);
+				qname = quote_path_relative(ent->name, prefix, &buf);
 				warning(_(msg_warn_remove_failed), qname);
 				errors++;
 			} else if (!quiet) {
-				qname = quote_path_relative(ent->name, -1, &buf, prefix);
+				qname = quote_path_relative(ent->name, prefix, &buf);
 				printf(dry_run ? _(msg_would_remove) : _(msg_remove), qname);
 			}
 		}

@@ -286,8 +286,7 @@ static int grep_sha1(struct grep_opt *opt, const unsigned char *sha1,
 	struct strbuf pathbuf = STRBUF_INIT;
 
 	if (opt->relative && opt->prefix_length) {
-		quote_path_relative(filename + tree_name_len, -1, &pathbuf,
-				    opt->prefix);
+		quote_path_relative(filename + tree_name_len, opt->prefix, &pathbuf);
 		strbuf_insert(&pathbuf, 0, filename, tree_name_len);
 	} else {
 		strbuf_addstr(&pathbuf, filename);

@@ -318,7 +317,7 @@ static int grep_file(struct grep_opt *opt, const char *filename)
 	struct strbuf buf = STRBUF_INIT;
 
 	if (opt->relative && opt->prefix_length)
-		quote_path_relative(filename, -1, &buf, opt->prefix);
+		quote_path_relative(filename, opt->prefix, &buf);
 	else
 		strbuf_addstr(&buf, filename);
 

@@ -391,7 +391,7 @@ int report_path_error(const char *ps_matched, const char **pathspec, const char
 		if (found_dup)
 			continue;
 
-		name = quote_path_relative(pathspec[num], -1, &sb, prefix);
+		name = quote_path_relative(pathspec[num], prefix, &sb);
 		error("pathspec '%s' did not match any file(s) known to git.",
 		      name);
 		errors++;

@@ -325,8 +325,8 @@ void write_name_quoted_relative(const char *name, size_t len,
 }
 
 /* quote path as relative to the given prefix */
-char *quote_path_relative(const char *in, int len,
-			  struct strbuf *out, const char *prefix)
+char *quote_path_relative(const char *in, const char *prefix,
+			  struct strbuf *out)
 {
 	struct strbuf sb = STRBUF_INIT;
 	const char *rel = relative_path(in, prefix, &sb);

@@ -334,9 +334,6 @@ char *quote_path_relative(const char *in, int len,
 	quote_c_style_counted(rel, strlen(rel), out, NULL, 0);
 	strbuf_release(&sb);
 
-	if (!out->len)
-		strbuf_addstr(out, "./");
-
 	return out->buf;
 }
 

@@ -65,8 +65,8 @@ extern void write_name_quoted_relative(const char *name, size_t len,
 		FILE *fp, int terminator);
 
 /* quote path as relative to the given prefix */
-extern char *quote_path_relative(const char *in, int len,
-			  struct strbuf *out, const char *prefix);
+extern char *quote_path_relative(const char *in, const char *prefix,
+			  struct strbuf *out);
 
 /* quoting as a string literal for other languages */
 extern void perl_quote_print(FILE *stream, const char *src);

@@ -243,7 +243,7 @@ static void wt_status_print_unmerged_data(struct wt_status *s,
 	struct strbuf onebuf = STRBUF_INIT;
 	const char *one, *how = _("bug");
 
-	one = quote_path(it->string, -1, &onebuf, s->prefix);
+	one = quote_path(it->string, s->prefix, &onebuf);
 	status_printf(s, color(WT_STATUS_HEADER, s), "\t");
 	switch (d->stagemask) {
 	case 1: how = _("both deleted:"); break;

@@ -297,8 +297,8 @@ static void wt_status_print_change_data(struct wt_status *s,
 		    change_type);
 	}
 
-	one = quote_path(one_name, -1, &onebuf, s->prefix);
-	two = quote_path(two_name, -1, &twobuf, s->prefix);
+	one = quote_path(one_name, s->prefix, &onebuf);
+	two = quote_path(two_name, s->prefix, &twobuf);
 
 	status_printf(s, color(WT_STATUS_HEADER, s), "\t");
 	switch (status) {

@@ -706,8 +706,7 @@ static void wt_status_print_other(struct wt_status *s,
 		struct string_list_item *it;
 		const char *path;
 		it = &(l->items[i]);
-		path = quote_path(it->string, strlen(it->string),
-				  &buf, s->prefix);
+		path = quote_path(it->string, s->prefix, &buf);
 		if (column_active(s->colopts)) {
 			string_list_append(&output, path);
 			continue;

@@ -1291,7 +1290,7 @@ static void wt_shortstatus_unmerged(struct string_list_item *it,
 	} else {
 		struct strbuf onebuf = STRBUF_INIT;
 		const char *one;
-		one = quote_path(it->string, -1, &onebuf, s->prefix);
+		one = quote_path(it->string, s->prefix, &onebuf);
 		printf(" %s\n", one);
 		strbuf_release(&onebuf);
 	}

@@ -1319,7 +1318,7 @@ static void wt_shortstatus_status(struct string_list_item *it,
 		struct strbuf onebuf = STRBUF_INIT;
 		const char *one;
 		if (d->head_path) {
-			one = quote_path(d->head_path, -1, &onebuf, s->prefix);
+			one = quote_path(d->head_path, s->prefix, &onebuf);
 			if (*one != '"' && strchr(one, ' ') != NULL) {
 				putchar('"');
 				strbuf_addch(&onebuf, '"');

@@ -1328,7 +1327,7 @@ static void wt_shortstatus_status(struct string_list_item *it,
 			printf("%s -> ", one);
 			strbuf_release(&onebuf);
 		}
-		one = quote_path(it->string, -1, &onebuf, s->prefix);
+		one = quote_path(it->string, s->prefix, &onebuf);
 		if (*one != '"' && strchr(one, ' ') != NULL) {
 			putchar('"');
 			strbuf_addch(&onebuf, '"');

@@ -1347,7 +1346,7 @@ static void wt_shortstatus_other(struct string_list_item *it,
 	} else {
 		struct strbuf onebuf = STRBUF_INIT;
 		const char *one;
-		one = quote_path(it->string, -1, &onebuf, s->prefix);
+		one = quote_path(it->string, s->prefix, &onebuf);
 		color_fprintf(s->fp, color(WT_STATUS_UNTRACKED, s), "%s", sign);
 		printf(" %s\n", one);
 		strbuf_release(&onebuf);

@@ -46,10 +46,12 @@ static const char *tag_modified = "";
 static const char *tag_skip_worktree = "";
 static const char *tag_resolve_undo = "";
 
-static void write_name(const char* name, size_t len)
+static void write_name(const char *name)
 {
-	write_name_quoted_relative(name, len, prefix, prefix_len, stdout,
-			line_terminator);
+
+	/* turn off prefix, if run with "--full-name" */
+	write_name_quoted_relative(name, prefix_len ? prefix : NULL,
+				   stdout, line_terminator);
 }
 
 static void show_dir_entry(const char *tag, struct dir_entry *ent)

@@ -63,7 +65,7 @@ static void show_dir_entry(const char *tag, struct dir_entry *ent)
 		return;
 
 	fputs(tag, stdout);
-	write_name(ent->name, ent->len);
+	write_name(ent->name);
 }
 
 static void show_other_files(struct dir_struct *dir)

@@ -163,7 +165,7 @@ static void show_ce_entry(const char *tag, struct cache_entry *ce)
 		       find_unique_abbrev(ce->sha1,abbrev),
 		       ce_stage(ce));
 	}
-	write_name(ce->name, ce_namelen(ce));
+	write_name(ce->name);
 	if (debug_mode) {
 		struct stat_data *sd = &ce->ce_stat_data;
 

@@ -198,7 +200,7 @@ static void show_ru_info(void)
 			printf("%s%06o %s %d\t", tag_resolve_undo, ui->mode[i],
 			       find_unique_abbrev(ui->sha1[i], abbrev),
 			       i + 1);
-			write_name(path, len);
+			write_name(path);
 		}
 	}
 }

@@ -312,8 +312,7 @@ void write_name_quotedpfx(const char *pfx, size_t pfxlen,
 	fputc(terminator, fp);
 }
 
-void write_name_quoted_relative(const char *name, size_t len,
-				const char *prefix, size_t prefix_len,
+void write_name_quoted_relative(const char *name, const char *prefix,
 				FILE *fp, int terminator)
 {
 	struct strbuf sb = STRBUF_INIT;

@@ -60,8 +60,7 @@ extern void quote_two_c_style(struct strbuf *, const char *, const char *, int);
 extern void write_name_quoted(const char *name, FILE *, int terminator);
 extern void write_name_quotedpfx(const char *pfx, size_t pfxlen,
                                  const char *name, FILE *, int terminator);
-extern void write_name_quoted_relative(const char *name, size_t len,
-		const char *prefix, size_t prefix_len,
+extern void write_name_quoted_relative(const char *name, const char *prefix,
 		FILE *fp, int terminator);
 
 /* quote path as relative to the given prefix */

@@ -15,6 +15,7 @@
 #include "quote.h"
 
 static int force = -1; /* unset */
+static struct string_list del_list = STRING_LIST_INIT_DUP;
 
 static const char *const builtin_clean_usage[] = {
 	N_("git clean [-d] [-f] [-n] [-q] [-e <pattern>] [-x | -X] [--] <paths>..."),

@@ -148,12 +149,13 @@ int cmd_clean(int argc, const char **argv, const char *prefix)
 	int dry_run = 0, remove_directories = 0, quiet = 0, ignored = 0;
 	int ignored_only = 0, config_set = 0, errors = 0, gone = 1;
 	int rm_flags = REMOVE_DIR_KEEP_NESTED_GIT;
-	struct strbuf directory = STRBUF_INIT;
+	struct strbuf abs_path = STRBUF_INIT;
 	struct dir_struct dir;
 	static const char **pathspec;
 	struct strbuf buf = STRBUF_INIT;
 	struct string_list exclude_list = STRING_LIST_INIT_NODUP;
 	struct exclude_list *el;
+	struct string_list_item *item;
 	const char *qname;
 	char *seen = NULL;
 	struct option options[] = {

@@ -223,6 +225,7 @@ int cmd_clean(int argc, const char **argv, const char *prefix)
 		int matches = 0;
 		struct cache_entry *ce;
 		struct stat st;
+		const char *rel;
 
 		/*
 		 * Remove the '/' at the end that directory

@@ -242,13 +245,8 @@ int cmd_clean(int argc, const char **argv, const char *prefix)
 				continue; /* Yup, this one exists unmerged */
 		}
 
-		/*
-		 * we might have removed this as part of earlier
-		 * recursive directory removal, so lstat() here could
-		 * fail with ENOENT.
-		 */
 		if (lstat(ent->name, &st))
-			continue;
+			die_errno("Cannot lstat '%s'", ent->name);
 
 		if (pathspec) {
 			memset(seen, 0, argc > 0 ? argc : 1);

@@ -257,33 +255,61 @@ int cmd_clean(int argc, const char **argv, const char *prefix)
 		}
 
 		if (S_ISDIR(st.st_mode)) {
-			strbuf_addstr(&directory, ent->name);
 			if (remove_directories || (matches == MATCHED_EXACTLY)) {
-				if (remove_dirs(&directory, prefix, rm_flags, dry_run, quiet, &gone))
-					errors++;
-				if (gone && !quiet) {
-					qname = quote_path_relative(directory.buf, prefix, &buf);
-					printf(dry_run ? _(msg_would_remove) : _(msg_remove), qname);
-				}
+				rel = relative_path(ent->name, prefix, &buf);
+				string_list_append(&del_list, rel);
 			}
-			strbuf_reset(&directory);
 		} else {
 			if (pathspec && !matches)
 				continue;
-			res = dry_run ? 0 : unlink(ent->name);
+			rel = relative_path(ent->name, prefix, &buf);
+			string_list_append(&del_list, rel);
+		}
+	}
+
+	/* TODO: do interactive git-clean here, which will modify del_list */
+
+	for_each_string_list_item(item, &del_list) {
+		struct stat st;
+
+		if (prefix)
+			strbuf_addstr(&abs_path, prefix);
+
+		strbuf_addstr(&abs_path, item->string);
+
+		/*
+		 * we might have removed this as part of earlier
+		 * recursive directory removal, so lstat() here could
+		 * fail with ENOENT.
+		 */
+		if (lstat(abs_path.buf, &st))
+			continue;
+
+		if (S_ISDIR(st.st_mode)) {
+			if (remove_dirs(&abs_path, prefix, rm_flags, dry_run, quiet, &gone))
+				errors++;
+			if (gone && !quiet) {
+				qname = quote_path_relative(item->string, NULL, &buf);
+				printf(dry_run ? _(msg_would_remove) : _(msg_remove), qname);
+			}
+		} else {
+			res = dry_run ? 0 : unlink(abs_path.buf);
 			if (res) {
-				qname = quote_path_relative(ent->name, prefix, &buf);
+				qname = quote_path_relative(item->string, NULL, &buf);
 				warning(_(msg_warn_remove_failed), qname);
 				errors++;
 			} else if (!quiet) {
-				qname = quote_path_relative(ent->name, prefix, &buf);
+				qname = quote_path_relative(item->string, NULL, &buf);
 				printf(dry_run ? _(msg_would_remove) : _(msg_remove), qname);
 			}
 		}
+		strbuf_reset(&abs_path);
 	}
 	free(seen);
 
-	strbuf_release(&directory);
+	strbuf_release(&abs_path);
+	strbuf_release(&buf);
+	string_list_clear(&del_list, 0);
 	string_list_clear(&exclude_list, 0);
 	return (errors != 0);
 }

@@ -8,7 +8,7 @@ git-clean - Remove untracked files from the working tree
 SYNOPSIS
 --------
 [verse]
-'git clean' [-d] [-f] [-n] [-q] [-e <pattern>] [-x | -X] [--] <path>...
+'git clean' [-d] [-f] [-i] [-n] [-q] [-e <pattern>] [-x | -X] [--] <path>...
 
 DESCRIPTION
 -----------

@@ -34,7 +34,13 @@ OPTIONS
 -f::
 --force::
 	If the Git configuration variable clean.requireForce is not set
-	to false, 'git clean' will refuse to run unless given -f or -n.
+	to false, 'git clean' will refuse to run unless given -f, -n or
+	-i.
+
+-i::
+--interactive::
+	Show what would be done and the user must confirm before actually
+	cleaning.
 
 -n::
 --dry-run::

@@ -15,10 +15,11 @@
 #include "quote.h"
 
 static int force = -1; /* unset */
+static int interactive;
 static struct string_list del_list = STRING_LIST_INIT_DUP;
 
 static const char *const builtin_clean_usage[] = {
-	N_("git clean [-d] [-f] [-n] [-q] [-e <pattern>] [-x | -X] [--] <paths>..."),
+	N_("git clean [-d] [-f] [-i] [-n] [-q] [-e <pattern>] [-x | -X] [--] <paths>..."),
 	NULL
 };
 

@@ -143,6 +144,50 @@ static int remove_dirs(struct strbuf *path, const char *prefix, int force_flag,
 	return ret;
 }
 
+static void interactive_main_loop(void)
+{
+	struct strbuf confirm = STRBUF_INIT;
+	struct strbuf buf = STRBUF_INIT;
+	struct string_list_item *item;
+	const char *qname;
+
+	while (del_list.nr) {
+		putchar('\n');
+		for_each_string_list_item(item, &del_list) {
+			qname = quote_path_relative(item->string, NULL, &buf);
+			printf(_(msg_would_remove), qname);
+		}
+		putchar('\n');
+
+		printf(_("Remove [y/n]? "));
+		if (strbuf_getline(&confirm, stdin, '\n') != EOF) {
+			strbuf_trim(&confirm);
+		} else {
+			/* Ctrl-D is the same as "quit" */
+			string_list_clear(&del_list, 0);
+			putchar('\n');
+			printf_ln("Bye.");
+			break;
+		}
+
+		if (confirm.len) {
+			if (!strncasecmp(confirm.buf, "yes", confirm.len)) {
+				break;
+			} else if (!strncasecmp(confirm.buf, "no", confirm.len) ||
+				   !strncasecmp(confirm.buf, "quit", confirm.len)) {
+				string_list_clear(&del_list, 0);
+				printf_ln("Bye.");
+				break;
+			} else {
+				continue;
+			}
+		}
+	}
+
+	strbuf_release(&buf);
+	strbuf_release(&confirm);
+}
+
 int cmd_clean(int argc, const char **argv, const char *prefix)
 {
 	int i, res;