cosmopolitan/third_party/musl/fnmatch.c

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/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi
Musl Libc
Copyright © 2005-2014 Rich Felker, et al.
Permission is hereby granted, free of charge, to any person obtaining
a copy of this software and associated documentation files (the
"Software"), to deal in the Software without restriction, including
without limitation the rights to use, copy, modify, merge, publish,
distribute, sublicense, and/or sell copies of the Software, and to
permit persons to whom the Software is furnished to do so, subject to
the following conditions:
The above copyright notice and this permission notice shall be
included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
#include "libc/limits.h"
#include "libc/str/str.h"
#include "third_party/musl/fnmatch.h"
/*
* An implementation of what I call the "Sea of Stars" algorithm for
* POSIX fnmatch(). The basic idea is that we factor the pattern into
* a head component (which we match first and can reject without ever
* measuring the length of the string), an optional tail component
* (which only exists if the pattern contains at least one star), and
* an optional "sea of stars", a set of star-separated components
* between the head and tail. After the head and tail matches have
* been removed from the input string, the components in the "sea of
* stars" are matched sequentially by searching for their first
* occurrence past the end of the previous match.
*
* - Rich Felker, April 2012
*/
asm(".ident\t\"\\n\\n\
Musl libc (MIT License)\\n\
Copyright 2005-2014 Rich Felker, et. al.\"");
asm(".include \"libc/disclaimer.inc\"");
#define END 0
#define UNMATCHABLE -2
#define BRACKET -3
#define QUESTION -4
#define STAR -5
static int FnmatchNextString(const char *str, size_t n, size_t *step) {
if (!n) {
*step = 0;
return 0;
}
if (str[0] >= 128U) {
wchar_t wc;
int k = mbtowc(&wc, str, n);
if (k < 0) {
*step = 1;
return -1;
}
*step = k;
return wc;
}
*step = 1;
return str[0];
}
static int FnmatchNextPattern(const char *pat, size_t m, size_t *step,
int flags) {
int esc = 0;
if (!m || !*pat) {
*step = 0;
return END;
}
*step = 1;
if (pat[0] == '\\' && pat[1] && !(flags & FNM_NOESCAPE)) {
*step = 2;
pat++;
esc = 1;
goto escaped;
}
if (pat[0] == '[') {
size_t k = 1;
if (k < m)
if (pat[k] == '^' || pat[k] == '!') k++;
if (k < m)
if (pat[k] == ']') k++;
for (; k < m && pat[k] && pat[k] != ']'; k++) {
if (k + 1 < m && pat[k + 1] && pat[k] == '[' &&
(pat[k + 1] == ':' || pat[k + 1] == '.' || pat[k + 1] == '=')) {
int z = pat[k + 1];
k += 2;
if (k < m && pat[k]) k++;
while (k < m && pat[k] && (pat[k - 1] != z || pat[k] != ']')) k++;
if (k == m || !pat[k]) break;
}
}
if (k == m || !pat[k]) {
*step = 1;
return '[';
}
*step = k + 1;
return BRACKET;
}
if (pat[0] == '*') return STAR;
if (pat[0] == '?') return QUESTION;
escaped:
if (pat[0] >= 128U) {
wchar_t wc;
int k = mbtowc(&wc, pat, m);
if (k < 0) {
*step = 0;
return UNMATCHABLE;
}
*step = k + esc;
return wc;
}
return pat[0];
}
static int FnmatchCaseFold(int k) {
int c = towupper(k);
return c == k ? towlower(k) : c;
}
static int FnmatchBracket(const char *p, int k, int kfold) {
wchar_t wc;
int inv = 0;
p++;
if (*p == '^' || *p == '!') {
inv = 1;
p++;
}
if (*p == ']') {
if (k == ']') return !inv;
p++;
} else if (*p == '-') {
if (k == '-') return !inv;
p++;
}
wc = p[-1];
for (; *p != ']'; p++) {
if (p[0] == '-' && p[1] != ']') {
wchar_t wc2;
int l = mbtowc(&wc2, p + 1, 4);
if (l < 0) return 0;
if (wc <= wc2)
if ((unsigned)k - wc <= wc2 - wc || (unsigned)kfold - wc <= wc2 - wc)
return !inv;
p += l - 1;
continue;
}
if (p[0] == '[' && (p[1] == ':' || p[1] == '.' || p[1] == '=')) {
const char *p0 = p + 2;
int z = p[1];
p += 3;
while (p[-1] != z || p[0] != ']') p++;
if (z == ':' && p - 1 - p0 < 16) {
char buf[16];
memcpy(buf, p0, p - 1 - p0);
buf[p - 1 - p0] = 0;
if (iswctype(k, wctype(buf)) || iswctype(kfold, wctype(buf)))
return !inv;
}
continue;
}
if (*p < 128U) {
wc = (unsigned char)*p;
} else {
int l = mbtowc(&wc, p, 4);
if (l < 0) return 0;
p += l - 1;
}
if (wc == k || wc == kfold) return !inv;
}
return inv;
}
static int FnmatchPerform(const char *pat, size_t m, const char *str, size_t n,
int flags) {
const char *p, *ptail, *endpat;
const char *s, *stail, *endstr;
size_t pinc, sinc, tailcnt = 0;
int c, k, kfold;
if (flags & FNM_PERIOD) {
if (*str == '.' && *pat != '.') {
return FNM_NOMATCH;
}
}
for (;;) {
switch ((c = FnmatchNextPattern(pat, m, &pinc, flags))) {
case UNMATCHABLE:
return FNM_NOMATCH;
case STAR:
pat++;
m--;
break;
default:
k = FnmatchNextString(str, n, &sinc);
if (k <= 0) return (c == END) ? 0 : FNM_NOMATCH;
str += sinc;
n -= sinc;
kfold = flags & FNM_CASEFOLD ? FnmatchCaseFold(k) : k;
if (c == BRACKET) {
if (!FnmatchBracket(pat, k, kfold)) return FNM_NOMATCH;
} else if (c != QUESTION && k != c && kfold != c) {
return FNM_NOMATCH;
}
pat += pinc;
m -= pinc;
continue;
}
break;
}
/* Compute real pat length if it was initially unknown/-1 */
m = strnlen(pat, m);
endpat = pat + m;
/* Find the last * in pat and count chars needed after it */
for (p = ptail = pat; p < endpat; p += pinc) {
switch (FnmatchNextPattern(p, endpat - p, &pinc, flags)) {
case UNMATCHABLE:
return FNM_NOMATCH;
case STAR:
tailcnt = 0;
ptail = p + 1;
break;
default:
tailcnt++;
break;
}
}
/* Past this point we need not check for UNMATCHABLE in pat,
* because all of pat has already been parsed once. */
/* Compute real str length if it was initially unknown/-1 */
n = strnlen(str, n);
endstr = str + n;
if (n < tailcnt) {
return FNM_NOMATCH;
}
/* Find the final tailcnt chars of str, accounting for UTF-8.
* On illegal sequences we may get it wrong, but in that case
* we necessarily have a matching failure anyway. */
for (s = endstr; s > str && tailcnt; tailcnt--) {
if (s[-1] < 128U || MB_CUR_MAX == 1) {
s--;
} else {
while ((unsigned char)*--s - 0x80U < 0x40 && s > str)
;
}
}
if (tailcnt) return FNM_NOMATCH;
stail = s;
/* Check that the pat and str tails match */
p = ptail;
for (;;) {
c = FnmatchNextPattern(p, endpat - p, &pinc, flags);
p += pinc;
if ((k = FnmatchNextString(s, endstr - s, &sinc)) <= 0) {
if (c != END) return FNM_NOMATCH;
break;
}
s += sinc;
kfold = flags & FNM_CASEFOLD ? FnmatchCaseFold(k) : k;
if (c == BRACKET) {
if (!FnmatchBracket(p - pinc, k, kfold)) return FNM_NOMATCH;
} else if (c != QUESTION && k != c && kfold != c) {
return FNM_NOMATCH;
}
}
/* We're all done with the tails now, so throw them out */
endstr = stail;
endpat = ptail;
/* Match pattern components until there are none left */
while (pat < endpat) {
p = pat;
s = str;
for (;;) {
c = FnmatchNextPattern(p, endpat - p, &pinc, flags);
p += pinc;
/* Encountering * completes/commits a component */
if (c == STAR) {
pat = p;
str = s;
break;
}
k = FnmatchNextString(s, endstr - s, &sinc);
if (!k) return FNM_NOMATCH;
kfold = flags & FNM_CASEFOLD ? FnmatchCaseFold(k) : k;
if (c == BRACKET) {
if (!FnmatchBracket(p - pinc, k, kfold)) break;
} else if (c != QUESTION && k != c && kfold != c) {
break;
}
s += sinc;
}
if (c == STAR) continue;
/* If we failed, advance str, by 1 char if it's a valid
* char, or past all invalid bytes otherwise. */
k = FnmatchNextString(str, endstr - str, &sinc);
if (k > 0) {
str += sinc;
} else {
str++;
while (FnmatchNextString(str, endstr - str, &sinc) < 0) {
str++;
}
}
}
return 0;
}
/**
* Matches filename.
*
* - `*` for wildcard
* - `?` for single character
* - `[abc]` to match character within set
* - `[!abc]` to match character not within set
* - `\*\?\[\]` for escaping above special syntax
*
* @see glob()
*/
int fnmatch(const char *pat, const char *str, int flags) {
const char *s, *p;
size_t inc;
int c;
if (flags & FNM_PATHNAME) {
for (;;) {
for (s = str; *s && *s != '/'; s++)
;
for (p = pat;
(c = FnmatchNextPattern(p, -1, &inc, flags)) != END && c != '/';
p += inc)
;
if (c != *s && (!*s || !(flags & FNM_LEADING_DIR))) return FNM_NOMATCH;
if (FnmatchPerform(pat, p - pat, str, s - str, flags)) return FNM_NOMATCH;
if (!c) return 0;
str = s + 1;
pat = p + inc;
}
} else if (flags & FNM_LEADING_DIR) {
for (s = str; *s; s++) {
if (*s != '/') continue;
if (!FnmatchPerform(pat, -1, str, s - str, flags)) return 0;
}
}
return FnmatchPerform(pat, -1, str, -1, flags);
}