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git/pathspec.c
Ævar Arnfjörð Bjarmason 5a7d41d849 docs & comments: replace mentions of "git-add--interactive.perl"
Now that we've removed "git-add--interactive.perl" let's replace
mentions of it with "add-interactive.c". In the case of the "git add"
documentation we were using it as an example filename, so the mention
wasn't wrong, but using a dead file is slightly confusing.

The "borrowed" comment here likewise isn't wrong, but let's mention
the successor file instead. In the case of pathspec.c the implied TODO
item should refer to the current code (and the comment may not even be
current, I didn't check).

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-02-06 15:03:34 -08:00

849 lines
21 KiB
C

#include "cache.h"
#include "config.h"
#include "dir.h"
#include "pathspec.h"
#include "attr.h"
#include "strvec.h"
#include "quote.h"
/*
* Finds which of the given pathspecs match items in the index.
*
* For each pathspec, sets the corresponding entry in the seen[] array
* (which should be specs items long, i.e. the same size as pathspec)
* to the nature of the "closest" (i.e. most specific) match found for
* that pathspec in the index, if it was a closer type of match than
* the existing entry. As an optimization, matching is skipped
* altogether if seen[] already only contains non-zero entries.
*
* If seen[] has not already been written to, it may make sense
* to use find_pathspecs_matching_against_index() instead.
*/
void add_pathspec_matches_against_index(const struct pathspec *pathspec,
struct index_state *istate,
char *seen,
enum ps_skip_worktree_action sw_action)
{
int num_unmatched = 0, i;
/*
* Since we are walking the index as if we were walking the directory,
* we have to mark the matched pathspec as seen; otherwise we will
* mistakenly think that the user gave a pathspec that did not match
* anything.
*/
for (i = 0; i < pathspec->nr; i++)
if (!seen[i])
num_unmatched++;
if (!num_unmatched)
return;
for (i = 0; i < istate->cache_nr; i++) {
const struct cache_entry *ce = istate->cache[i];
if (sw_action == PS_IGNORE_SKIP_WORKTREE &&
(ce_skip_worktree(ce) || !path_in_sparse_checkout(ce->name, istate)))
continue;
ce_path_match(istate, ce, pathspec, seen);
}
}
/*
* Finds which of the given pathspecs match items in the index.
*
* This is a one-shot wrapper around add_pathspec_matches_against_index()
* which allocates, populates, and returns a seen[] array indicating the
* nature of the "closest" (i.e. most specific) matches which each of the
* given pathspecs achieves against all items in the index.
*/
char *find_pathspecs_matching_against_index(const struct pathspec *pathspec,
struct index_state *istate,
enum ps_skip_worktree_action sw_action)
{
char *seen = xcalloc(pathspec->nr, 1);
add_pathspec_matches_against_index(pathspec, istate, seen, sw_action);
return seen;
}
char *find_pathspecs_matching_skip_worktree(const struct pathspec *pathspec)
{
struct index_state *istate = the_repository->index;
char *seen = xcalloc(pathspec->nr, 1);
int i;
for (i = 0; i < istate->cache_nr; i++) {
struct cache_entry *ce = istate->cache[i];
if (ce_skip_worktree(ce) || !path_in_sparse_checkout(ce->name, istate))
ce_path_match(istate, ce, pathspec, seen);
}
return seen;
}
/*
* Magic pathspec
*
* Possible future magic semantics include stuff like:
*
* { PATHSPEC_RECURSIVE, '*', "recursive" },
* { PATHSPEC_REGEXP, '\0', "regexp" },
*
*/
static struct pathspec_magic {
unsigned bit;
char mnemonic; /* this cannot be ':'! */
const char *name;
} pathspec_magic[] = {
{ PATHSPEC_FROMTOP, '/', "top" },
{ PATHSPEC_LITERAL, '\0', "literal" },
{ PATHSPEC_GLOB, '\0', "glob" },
{ PATHSPEC_ICASE, '\0', "icase" },
{ PATHSPEC_EXCLUDE, '!', "exclude" },
{ PATHSPEC_ATTR, '\0', "attr" },
};
static void prefix_magic(struct strbuf *sb, int prefixlen, unsigned magic)
{
int i;
strbuf_addstr(sb, ":(");
for (i = 0; i < ARRAY_SIZE(pathspec_magic); i++)
if (magic & pathspec_magic[i].bit) {
if (sb->buf[sb->len - 1] != '(')
strbuf_addch(sb, ',');
strbuf_addstr(sb, pathspec_magic[i].name);
}
strbuf_addf(sb, ",prefix:%d)", prefixlen);
}
static size_t strcspn_escaped(const char *s, const char *stop)
{
const char *i;
for (i = s; *i; i++) {
/* skip the escaped character */
if (i[0] == '\\' && i[1]) {
i++;
continue;
}
if (strchr(stop, *i))
break;
}
return i - s;
}
static inline int invalid_value_char(const char ch)
{
if (isalnum(ch) || strchr(",-_", ch))
return 0;
return -1;
}
static char *attr_value_unescape(const char *value)
{
const char *src;
char *dst, *ret;
ret = xmallocz(strlen(value));
for (src = value, dst = ret; *src; src++, dst++) {
if (*src == '\\') {
if (!src[1])
die(_("Escape character '\\' not allowed as "
"last character in attr value"));
src++;
}
if (invalid_value_char(*src))
die("cannot use '%c' for value matching", *src);
*dst = *src;
}
*dst = '\0';
return ret;
}
static void parse_pathspec_attr_match(struct pathspec_item *item, const char *value)
{
struct string_list_item *si;
struct string_list list = STRING_LIST_INIT_DUP;
if (item->attr_check || item->attr_match)
die(_("Only one 'attr:' specification is allowed."));
if (!value || !*value)
die(_("attr spec must not be empty"));
string_list_split(&list, value, ' ', -1);
string_list_remove_empty_items(&list, 0);
item->attr_check = attr_check_alloc();
CALLOC_ARRAY(item->attr_match, list.nr);
for_each_string_list_item(si, &list) {
size_t attr_len;
char *attr_name;
const struct git_attr *a;
int j = item->attr_match_nr++;
const char *attr = si->string;
struct attr_match *am = &item->attr_match[j];
switch (*attr) {
case '!':
am->match_mode = MATCH_UNSPECIFIED;
attr++;
attr_len = strlen(attr);
break;
case '-':
am->match_mode = MATCH_UNSET;
attr++;
attr_len = strlen(attr);
break;
default:
attr_len = strcspn(attr, "=");
if (attr[attr_len] != '=')
am->match_mode = MATCH_SET;
else {
const char *v = &attr[attr_len + 1];
am->match_mode = MATCH_VALUE;
am->value = attr_value_unescape(v);
}
break;
}
attr_name = xmemdupz(attr, attr_len);
a = git_attr(attr_name);
if (!a)
die(_("invalid attribute name %s"), attr_name);
attr_check_append(item->attr_check, a);
free(attr_name);
}
if (item->attr_check->nr != item->attr_match_nr)
BUG("should have same number of entries");
string_list_clear(&list, 0);
}
static inline int get_literal_global(void)
{
static int literal = -1;
if (literal < 0)
literal = git_env_bool(GIT_LITERAL_PATHSPECS_ENVIRONMENT, 0);
return literal;
}
static inline int get_glob_global(void)
{
static int glob = -1;
if (glob < 0)
glob = git_env_bool(GIT_GLOB_PATHSPECS_ENVIRONMENT, 0);
return glob;
}
static inline int get_noglob_global(void)
{
static int noglob = -1;
if (noglob < 0)
noglob = git_env_bool(GIT_NOGLOB_PATHSPECS_ENVIRONMENT, 0);
return noglob;
}
static inline int get_icase_global(void)
{
static int icase = -1;
if (icase < 0)
icase = git_env_bool(GIT_ICASE_PATHSPECS_ENVIRONMENT, 0);
return icase;
}
static int get_global_magic(int element_magic)
{
int global_magic = 0;
if (get_literal_global())
global_magic |= PATHSPEC_LITERAL;
/* --glob-pathspec is overridden by :(literal) */
if (get_glob_global() && !(element_magic & PATHSPEC_LITERAL))
global_magic |= PATHSPEC_GLOB;
if (get_glob_global() && get_noglob_global())
die(_("global 'glob' and 'noglob' pathspec settings are incompatible"));
if (get_icase_global())
global_magic |= PATHSPEC_ICASE;
if ((global_magic & PATHSPEC_LITERAL) &&
(global_magic & ~PATHSPEC_LITERAL))
die(_("global 'literal' pathspec setting is incompatible "
"with all other global pathspec settings"));
/* --noglob-pathspec adds :(literal) _unless_ :(glob) is specified */
if (get_noglob_global() && !(element_magic & PATHSPEC_GLOB))
global_magic |= PATHSPEC_LITERAL;
return global_magic;
}
/*
* Parse the pathspec element looking for long magic
*
* saves all magic in 'magic'
* if prefix magic is used, save the prefix length in 'prefix_len'
* returns the position in 'elem' after all magic has been parsed
*/
static const char *parse_long_magic(unsigned *magic, int *prefix_len,
struct pathspec_item *item,
const char *elem)
{
const char *pos;
const char *nextat;
for (pos = elem + 2; *pos && *pos != ')'; pos = nextat) {
size_t len = strcspn_escaped(pos, ",)");
int i;
if (pos[len] == ',')
nextat = pos + len + 1; /* handle ',' */
else
nextat = pos + len; /* handle ')' and '\0' */
if (!len)
continue;
if (starts_with(pos, "prefix:")) {
char *endptr;
*prefix_len = strtol(pos + 7, &endptr, 10);
if (endptr - pos != len)
die(_("invalid parameter for pathspec magic 'prefix'"));
continue;
}
if (starts_with(pos, "attr:")) {
char *attr_body = xmemdupz(pos + 5, len - 5);
parse_pathspec_attr_match(item, attr_body);
*magic |= PATHSPEC_ATTR;
free(attr_body);
continue;
}
for (i = 0; i < ARRAY_SIZE(pathspec_magic); i++) {
if (strlen(pathspec_magic[i].name) == len &&
!strncmp(pathspec_magic[i].name, pos, len)) {
*magic |= pathspec_magic[i].bit;
break;
}
}
if (ARRAY_SIZE(pathspec_magic) <= i)
die(_("Invalid pathspec magic '%.*s' in '%s'"),
(int) len, pos, elem);
}
if (*pos != ')')
die(_("Missing ')' at the end of pathspec magic in '%s'"),
elem);
pos++;
return pos;
}
/*
* Parse the pathspec element looking for short magic
*
* saves all magic in 'magic'
* returns the position in 'elem' after all magic has been parsed
*/
static const char *parse_short_magic(unsigned *magic, const char *elem)
{
const char *pos;
for (pos = elem + 1; *pos && *pos != ':'; pos++) {
char ch = *pos;
int i;
/* Special case alias for '!' */
if (ch == '^') {
*magic |= PATHSPEC_EXCLUDE;
continue;
}
if (!is_pathspec_magic(ch))
break;
for (i = 0; i < ARRAY_SIZE(pathspec_magic); i++) {
if (pathspec_magic[i].mnemonic == ch) {
*magic |= pathspec_magic[i].bit;
break;
}
}
if (ARRAY_SIZE(pathspec_magic) <= i)
die(_("Unimplemented pathspec magic '%c' in '%s'"),
ch, elem);
}
if (*pos == ':')
pos++;
return pos;
}
static const char *parse_element_magic(unsigned *magic, int *prefix_len,
struct pathspec_item *item,
const char *elem)
{
if (elem[0] != ':' || get_literal_global())
return elem; /* nothing to do */
else if (elem[1] == '(')
/* longhand */
return parse_long_magic(magic, prefix_len, item, elem);
else
/* shorthand */
return parse_short_magic(magic, elem);
}
/*
* Perform the initialization of a pathspec_item based on a pathspec element.
*/
static void init_pathspec_item(struct pathspec_item *item, unsigned flags,
const char *prefix, int prefixlen,
const char *elt)
{
unsigned magic = 0, element_magic = 0;
const char *copyfrom = elt;
char *match;
int pathspec_prefix = -1;
item->attr_check = NULL;
item->attr_match = NULL;
item->attr_match_nr = 0;
/* PATHSPEC_LITERAL_PATH ignores magic */
if (flags & PATHSPEC_LITERAL_PATH) {
magic = PATHSPEC_LITERAL;
} else {
copyfrom = parse_element_magic(&element_magic,
&pathspec_prefix,
item,
elt);
magic |= element_magic;
magic |= get_global_magic(element_magic);
}
item->magic = magic;
if (pathspec_prefix >= 0 &&
(prefixlen || (prefix && *prefix)))
BUG("'prefix' magic is supposed to be used at worktree's root");
if ((magic & PATHSPEC_LITERAL) && (magic & PATHSPEC_GLOB))
die(_("%s: 'literal' and 'glob' are incompatible"), elt);
/* Create match string which will be used for pathspec matching */
if (pathspec_prefix >= 0) {
match = xstrdup(copyfrom);
prefixlen = pathspec_prefix;
} else if (magic & PATHSPEC_FROMTOP) {
match = xstrdup(copyfrom);
prefixlen = 0;
} else {
match = prefix_path_gently(prefix, prefixlen,
&prefixlen, copyfrom);
if (!match) {
const char *hint_path = get_git_work_tree();
if (!hint_path)
hint_path = get_git_dir();
die(_("%s: '%s' is outside repository at '%s'"), elt,
copyfrom, absolute_path(hint_path));
}
}
item->match = match;
item->len = strlen(item->match);
item->prefix = prefixlen;
/*
* Prefix the pathspec (keep all magic) and assign to
* original. Useful for passing to another command.
*/
if ((flags & PATHSPEC_PREFIX_ORIGIN) &&
!get_literal_global()) {
struct strbuf sb = STRBUF_INIT;
/* Preserve the actual prefix length of each pattern */
prefix_magic(&sb, prefixlen, element_magic);
strbuf_addstr(&sb, match);
item->original = strbuf_detach(&sb, NULL);
} else {
item->original = xstrdup(elt);
}
if (magic & PATHSPEC_LITERAL) {
item->nowildcard_len = item->len;
} else {
item->nowildcard_len = simple_length(item->match);
if (item->nowildcard_len < prefixlen)
item->nowildcard_len = prefixlen;
}
item->flags = 0;
if (magic & PATHSPEC_GLOB) {
/*
* FIXME: should we enable ONESTAR in _GLOB for
* pattern "* * / * . c"?
*/
} else {
if (item->nowildcard_len < item->len &&
item->match[item->nowildcard_len] == '*' &&
no_wildcard(item->match + item->nowildcard_len + 1))
item->flags |= PATHSPEC_ONESTAR;
}
/* sanity checks, pathspec matchers assume these are sane */
if (item->nowildcard_len > item->len ||
item->prefix > item->len) {
BUG("error initializing pathspec_item");
}
}
static int pathspec_item_cmp(const void *a_, const void *b_)
{
struct pathspec_item *a, *b;
a = (struct pathspec_item *)a_;
b = (struct pathspec_item *)b_;
return strcmp(a->match, b->match);
}
static void NORETURN unsupported_magic(const char *pattern,
unsigned magic)
{
struct strbuf sb = STRBUF_INIT;
int i;
for (i = 0; i < ARRAY_SIZE(pathspec_magic); i++) {
const struct pathspec_magic *m = pathspec_magic + i;
if (!(magic & m->bit))
continue;
if (sb.len)
strbuf_addstr(&sb, ", ");
if (m->mnemonic)
strbuf_addf(&sb, _("'%s' (mnemonic: '%c')"),
m->name, m->mnemonic);
else
strbuf_addf(&sb, "'%s'", m->name);
}
/*
* We may want to substitute "this command" with a command
* name. E.g. when "git add -p" or "git add -i" dies when running
* "checkout -p"
*/
die(_("%s: pathspec magic not supported by this command: %s"),
pattern, sb.buf);
}
void parse_pathspec(struct pathspec *pathspec,
unsigned magic_mask, unsigned flags,
const char *prefix, const char **argv)
{
struct pathspec_item *item;
const char *entry = argv ? *argv : NULL;
int i, n, prefixlen, nr_exclude = 0;
memset(pathspec, 0, sizeof(*pathspec));
if (flags & PATHSPEC_MAXDEPTH_VALID)
pathspec->magic |= PATHSPEC_MAXDEPTH;
/* No arguments, no prefix -> no pathspec */
if (!entry && !prefix)
return;
if ((flags & PATHSPEC_PREFER_CWD) &&
(flags & PATHSPEC_PREFER_FULL))
BUG("PATHSPEC_PREFER_CWD and PATHSPEC_PREFER_FULL are incompatible");
/* No arguments with prefix -> prefix pathspec */
if (!entry) {
if (flags & PATHSPEC_PREFER_FULL)
return;
if (!(flags & PATHSPEC_PREFER_CWD))
BUG("PATHSPEC_PREFER_CWD requires arguments");
pathspec->items = CALLOC_ARRAY(item, 1);
item->match = xstrdup(prefix);
item->original = xstrdup(prefix);
item->nowildcard_len = item->len = strlen(prefix);
item->prefix = item->len;
pathspec->nr = 1;
return;
}
n = 0;
while (argv[n]) {
if (*argv[n] == '\0')
die("empty string is not a valid pathspec. "
"please use . instead if you meant to match all paths");
n++;
}
pathspec->nr = n;
ALLOC_ARRAY(pathspec->items, n + 1);
item = pathspec->items;
prefixlen = prefix ? strlen(prefix) : 0;
for (i = 0; i < n; i++) {
entry = argv[i];
init_pathspec_item(item + i, flags, prefix, prefixlen, entry);
if (item[i].magic & PATHSPEC_EXCLUDE)
nr_exclude++;
if (item[i].magic & magic_mask)
unsupported_magic(entry, item[i].magic & magic_mask);
if ((flags & PATHSPEC_SYMLINK_LEADING_PATH) &&
has_symlink_leading_path(item[i].match, item[i].len)) {
die(_("pathspec '%s' is beyond a symbolic link"), entry);
}
if (item[i].nowildcard_len < item[i].len)
pathspec->has_wildcard = 1;
pathspec->magic |= item[i].magic;
}
/*
* If everything is an exclude pattern, add one positive pattern
* that matches everything. We allocated an extra one for this.
*/
if (nr_exclude == n) {
int plen = (!(flags & PATHSPEC_PREFER_CWD)) ? 0 : prefixlen;
init_pathspec_item(item + n, 0, prefix, plen, ".");
pathspec->nr++;
}
if (pathspec->magic & PATHSPEC_MAXDEPTH) {
if (flags & PATHSPEC_KEEP_ORDER)
BUG("PATHSPEC_MAXDEPTH_VALID and PATHSPEC_KEEP_ORDER are incompatible");
QSORT(pathspec->items, pathspec->nr, pathspec_item_cmp);
}
}
void parse_pathspec_file(struct pathspec *pathspec, unsigned magic_mask,
unsigned flags, const char *prefix,
const char *file, int nul_term_line)
{
struct strvec parsed_file = STRVEC_INIT;
strbuf_getline_fn getline_fn = nul_term_line ? strbuf_getline_nul :
strbuf_getline;
struct strbuf buf = STRBUF_INIT;
struct strbuf unquoted = STRBUF_INIT;
FILE *in;
if (!strcmp(file, "-"))
in = stdin;
else
in = xfopen(file, "r");
while (getline_fn(&buf, in) != EOF) {
if (!nul_term_line && buf.buf[0] == '"') {
strbuf_reset(&unquoted);
if (unquote_c_style(&unquoted, buf.buf, NULL))
die(_("line is badly quoted: %s"), buf.buf);
strbuf_swap(&buf, &unquoted);
}
strvec_push(&parsed_file, buf.buf);
strbuf_reset(&buf);
}
strbuf_release(&unquoted);
strbuf_release(&buf);
if (in != stdin)
fclose(in);
parse_pathspec(pathspec, magic_mask, flags, prefix, parsed_file.v);
strvec_clear(&parsed_file);
}
void copy_pathspec(struct pathspec *dst, const struct pathspec *src)
{
int i, j;
*dst = *src;
DUP_ARRAY(dst->items, src->items, dst->nr);
for (i = 0; i < dst->nr; i++) {
struct pathspec_item *d = &dst->items[i];
struct pathspec_item *s = &src->items[i];
d->match = xstrdup(s->match);
d->original = xstrdup(s->original);
DUP_ARRAY(d->attr_match, s->attr_match, d->attr_match_nr);
for (j = 0; j < d->attr_match_nr; j++) {
const char *value = s->attr_match[j].value;
d->attr_match[j].value = xstrdup_or_null(value);
}
d->attr_check = attr_check_dup(s->attr_check);
}
}
void clear_pathspec(struct pathspec *pathspec)
{
int i, j;
for (i = 0; i < pathspec->nr; i++) {
free(pathspec->items[i].match);
free(pathspec->items[i].original);
for (j = 0; j < pathspec->items[i].attr_match_nr; j++)
free(pathspec->items[i].attr_match[j].value);
free(pathspec->items[i].attr_match);
if (pathspec->items[i].attr_check)
attr_check_free(pathspec->items[i].attr_check);
}
FREE_AND_NULL(pathspec->items);
pathspec->nr = 0;
}
int match_pathspec_attrs(struct index_state *istate,
const char *name, int namelen,
const struct pathspec_item *item)
{
int i;
char *to_free = NULL;
if (name[namelen])
name = to_free = xmemdupz(name, namelen);
git_check_attr(istate, NULL, name, item->attr_check);
free(to_free);
for (i = 0; i < item->attr_match_nr; i++) {
const char *value;
int matched;
enum attr_match_mode match_mode;
value = item->attr_check->items[i].value;
match_mode = item->attr_match[i].match_mode;
if (ATTR_TRUE(value))
matched = (match_mode == MATCH_SET);
else if (ATTR_FALSE(value))
matched = (match_mode == MATCH_UNSET);
else if (ATTR_UNSET(value))
matched = (match_mode == MATCH_UNSPECIFIED);
else
matched = (match_mode == MATCH_VALUE &&
!strcmp(item->attr_match[i].value, value));
if (!matched)
return 0;
}
return 1;
}
int pathspec_needs_expanded_index(struct index_state *istate,
const struct pathspec *pathspec)
{
unsigned int i, pos;
int res = 0;
char *skip_worktree_seen = NULL;
/*
* If index is not sparse, no index expansion is needed.
*/
if (!istate->sparse_index)
return 0;
/*
* When using a magic pathspec, assume for the sake of simplicity that
* the index needs to be expanded to match all matchable files.
*/
if (pathspec->magic)
return 1;
for (i = 0; i < pathspec->nr; i++) {
struct pathspec_item item = pathspec->items[i];
/*
* If the pathspec item has a wildcard, the index should be expanded
* if the pathspec has the possibility of matching a subset of entries inside
* of a sparse directory (but not the entire directory).
*
* If the pathspec item is a literal path, the index only needs to be expanded
* if a) the pathspec isn't in the sparse checkout cone (to make sure we don't
* expand for in-cone files) and b) it doesn't match any sparse directories
* (since we can reset whole sparse directories without expanding them).
*/
if (item.nowildcard_len < item.len) {
/*
* Special case: if the pattern is a path inside the cone
* followed by only wildcards, the pattern cannot match
* partial sparse directories, so we know we don't need to
* expand the index.
*
* Examples:
* - in-cone/foo***: doesn't need expanded index
* - not-in-cone/bar*: may need expanded index
* - **.c: may need expanded index
*/
if (strspn(item.original + item.nowildcard_len, "*") == item.len - item.nowildcard_len &&
path_in_cone_mode_sparse_checkout(item.original, istate))
continue;
for (pos = 0; pos < istate->cache_nr; pos++) {
struct cache_entry *ce = istate->cache[pos];
if (!S_ISSPARSEDIR(ce->ce_mode))
continue;
/*
* If the pre-wildcard length is longer than the sparse
* directory name and the sparse directory is the first
* component of the pathspec, need to expand the index.
*/
if (item.nowildcard_len > ce_namelen(ce) &&
!strncmp(item.original, ce->name, ce_namelen(ce))) {
res = 1;
break;
}
/*
* If the pre-wildcard length is shorter than the sparse
* directory and the pathspec does not match the whole
* directory, need to expand the index.
*/
if (!strncmp(item.original, ce->name, item.nowildcard_len) &&
wildmatch(item.original, ce->name, 0)) {
res = 1;
break;
}
}
} else if (!path_in_cone_mode_sparse_checkout(item.original, istate) &&
!matches_skip_worktree(pathspec, i, &skip_worktree_seen))
res = 1;
if (res > 0)
break;
}
free(skip_worktree_seen);
return res;
}