cosmopolitan/third_party/musl/fnmatch.c

369 lines
11 KiB
C

/*-*- 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);
}