musl-tcc/src/regex/glob.c

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2022-03-20 04:48:53 -04:00
#define _BSD_SOURCE
#include <glob.h>
#include <fnmatch.h>
#include <sys/stat.h>
#include <dirent.h>
#include <limits.h>
#include <string.h>
#include <stdlib.h>
#include <errno.h>
#include <stddef.h>
#include <unistd.h>
#include <pwd.h>
struct match
{
struct match *next;
char name[];
};
static int append(struct match **tail, const char *name, size_t len, int mark)
{
struct match *new = malloc(sizeof(struct match) + len + 2);
if (!new) return -1;
(*tail)->next = new;
new->next = NULL;
memcpy(new->name, name, len+1);
if (mark && len && name[len-1]!='/') {
new->name[len] = '/';
new->name[len+1] = 0;
}
*tail = new;
return 0;
}
static int do_glob(char *buf, size_t pos, int type, char *pat, int flags, int (*errfunc)(const char *path, int err), struct match **tail)
{
/* If GLOB_MARK is unused, we don't care about type. */
if (!type && !(flags & GLOB_MARK)) type = DT_REG;
/* Special-case the remaining pattern being all slashes, in
* which case we can use caller-passed type if it's a dir. */
if (*pat && type!=DT_DIR) type = 0;
while (pos+1 < PATH_MAX && *pat=='/') buf[pos++] = *pat++;
/* Consume maximal [escaped-]literal prefix of pattern, copying
* and un-escaping it to the running buffer as we go. */
ptrdiff_t i=0, j=0;
int in_bracket = 0, overflow = 0;
for (; pat[i]!='*' && pat[i]!='?' && (!in_bracket || pat[i]!=']'); i++) {
if (!pat[i]) {
if (overflow) return 0;
pat += i;
pos += j;
i = j = 0;
break;
} else if (pat[i] == '[') {
in_bracket = 1;
} else if (pat[i] == '\\' && !(flags & GLOB_NOESCAPE)) {
/* Backslashes inside a bracket are (at least by
* our interpretation) non-special, so if next
* char is ']' we have a complete expression. */
if (in_bracket && pat[i+1]==']') break;
/* Unpaired final backslash never matches. */
if (!pat[i+1]) return 0;
i++;
}
if (pat[i] == '/') {
if (overflow) return 0;
in_bracket = 0;
pat += i+1;
i = -1;
pos += j+1;
j = -1;
}
/* Only store a character if it fits in the buffer, but if
* a potential bracket expression is open, the overflow
* must be remembered and handled later only if the bracket
* is unterminated (and thereby a literal), so as not to
* disallow long bracket expressions with short matches. */
if (pos+(j+1) < PATH_MAX) {
buf[pos+j++] = pat[i];
} else if (in_bracket) {
overflow = 1;
} else {
return 0;
}
/* If we consume any new components, the caller-passed type
* or dummy type from above is no longer valid. */
type = 0;
}
buf[pos] = 0;
if (!*pat) {
/* If we consumed any components above, or if GLOB_MARK is
* requested and we don't yet know if the match is a dir,
* we must confirm the file exists and/or determine its type.
*
* If marking dirs, symlink type is inconclusive; we need the
* type for the symlink target, and therefore must try stat
* first unless type is known not to be a symlink. Otherwise,
* or if that fails, use lstat for determining existence to
* avoid false negatives in the case of broken symlinks. */
struct stat st;
if ((flags & GLOB_MARK) && (!type||type==DT_LNK) && !stat(buf, &st)) {
if (S_ISDIR(st.st_mode)) type = DT_DIR;
else type = DT_REG;
}
if (!type && lstat(buf, &st)) {
if (errno!=ENOENT && (errfunc(buf, errno) || (flags & GLOB_ERR)))
return GLOB_ABORTED;
return 0;
}
if (append(tail, buf, pos, (flags & GLOB_MARK) && type==DT_DIR))
return GLOB_NOSPACE;
return 0;
}
char *p2 = strchr(pat, '/'), saved_sep = '/';
/* Check if the '/' was escaped and, if so, remove the escape char
* so that it will not be unpaired when passed to fnmatch. */
if (p2 && !(flags & GLOB_NOESCAPE)) {
char *p;
for (p=p2; p>pat && p[-1]=='\\'; p--);
if ((p2-p)%2) {
p2--;
saved_sep = '\\';
}
}
DIR *dir = opendir(pos ? buf : ".");
if (!dir) {
if (errfunc(buf, errno) || (flags & GLOB_ERR))
return GLOB_ABORTED;
return 0;
}
int old_errno = errno;
struct dirent *de;
while (errno=0, de=readdir(dir)) {
/* Quickly skip non-directories when there's pattern left. */
if (p2 && de->d_type && de->d_type!=DT_DIR && de->d_type!=DT_LNK)
continue;
size_t l = strlen(de->d_name);
if (l >= PATH_MAX-pos) continue;
if (p2) *p2 = 0;
int fnm_flags= ((flags & GLOB_NOESCAPE) ? FNM_NOESCAPE : 0)
| ((!(flags & GLOB_PERIOD)) ? FNM_PERIOD : 0);
if (fnmatch(pat, de->d_name, fnm_flags))
continue;
/* With GLOB_PERIOD, don't allow matching . or .. unless
* fnmatch would match them with FNM_PERIOD rules in effect. */
if (p2 && (flags & GLOB_PERIOD) && de->d_name[0]=='.'
&& (!de->d_name[1] || de->d_name[1]=='.' && !de->d_name[2])
&& fnmatch(pat, de->d_name, fnm_flags | FNM_PERIOD))
continue;
memcpy(buf+pos, de->d_name, l+1);
if (p2) *p2 = saved_sep;
int r = do_glob(buf, pos+l, de->d_type, p2 ? p2 : "", flags, errfunc, tail);
if (r) {
closedir(dir);
return r;
}
}
int readerr = errno;
if (p2) *p2 = saved_sep;
closedir(dir);
if (readerr && (errfunc(buf, errno) || (flags & GLOB_ERR)))
return GLOB_ABORTED;
errno = old_errno;
return 0;
}
static int ignore_err(const char *path, int err)
{
return 0;
}
static void freelist(struct match *head)
{
struct match *match, *next;
for (match=head->next; match; match=next) {
next = match->next;
free(match);
}
}
static int sort(const void *a, const void *b)
{
return strcmp(*(const char **)a, *(const char **)b);
}
static int expand_tilde(char **pat, char *buf, size_t *pos)
{
char *p = *pat + 1;
size_t i = 0;
char delim, *name_end = __strchrnul(p, '/');
if ((delim = *name_end)) *name_end++ = 0;
*pat = name_end;
char *home = *p ? NULL : getenv("HOME");
if (!home) {
struct passwd pw, *res;
switch (*p ? getpwnam_r(p, &pw, buf, PATH_MAX, &res)
: getpwuid_r(getuid(), &pw, buf, PATH_MAX, &res)) {
case ENOMEM:
return GLOB_NOSPACE;
case 0:
if (!res)
default:
return GLOB_NOMATCH;
}
home = pw.pw_dir;
}
while (i < PATH_MAX - 2 && *home)
buf[i++] = *home++;
if (*home)
return GLOB_NOMATCH;
if ((buf[i] = delim))
buf[++i] = 0;
*pos = i;
return 0;
}
int glob(const char *restrict pat, int flags, int (*errfunc)(const char *path, int err), glob_t *restrict g)
{
struct match head = { .next = NULL }, *tail = &head;
size_t cnt, i;
size_t offs = (flags & GLOB_DOOFFS) ? g->gl_offs : 0;
int error = 0;
char buf[PATH_MAX];
if (!errfunc) errfunc = ignore_err;
if (!(flags & GLOB_APPEND)) {
g->gl_offs = offs;
g->gl_pathc = 0;
g->gl_pathv = NULL;
}
if (*pat) {
char *p = strdup(pat);
if (!p) return GLOB_NOSPACE;
buf[0] = 0;
size_t pos = 0;
char *s = p;
if ((flags & (GLOB_TILDE | GLOB_TILDE_CHECK)) && *p == '~')
error = expand_tilde(&s, buf, &pos);
if (!error)
error = do_glob(buf, pos, 0, s, flags, errfunc, &tail);
free(p);
}
if (error == GLOB_NOSPACE) {
freelist(&head);
return error;
}
for (cnt=0, tail=head.next; tail; tail=tail->next, cnt++);
if (!cnt) {
if (flags & GLOB_NOCHECK) {
tail = &head;
if (append(&tail, pat, strlen(pat), 0))
return GLOB_NOSPACE;
cnt++;
} else
return GLOB_NOMATCH;
}
if (flags & GLOB_APPEND) {
char **pathv = realloc(g->gl_pathv, (offs + g->gl_pathc + cnt + 1) * sizeof(char *));
if (!pathv) {
freelist(&head);
return GLOB_NOSPACE;
}
g->gl_pathv = pathv;
offs += g->gl_pathc;
} else {
g->gl_pathv = malloc((offs + cnt + 1) * sizeof(char *));
if (!g->gl_pathv) {
freelist(&head);
return GLOB_NOSPACE;
}
for (i=0; i<offs; i++)
g->gl_pathv[i] = NULL;
}
for (i=0, tail=head.next; i<cnt; tail=tail->next, i++)
g->gl_pathv[offs + i] = tail->name;
g->gl_pathv[offs + i] = NULL;
g->gl_pathc += cnt;
if (!(flags & GLOB_NOSORT))
qsort(g->gl_pathv+offs, cnt, sizeof(char *), sort);
return error;
}
void globfree(glob_t *g)
{
size_t i;
for (i=0; i<g->gl_pathc; i++)
free(g->gl_pathv[g->gl_offs + i] - offsetof(struct match, name));
free(g->gl_pathv);
g->gl_pathc = 0;
g->gl_pathv = NULL;
}
weak_alias(glob, glob64);
weak_alias(globfree, globfree64);