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| | #include <wordexp.h>
#include <unistd.h>
#include <stdio.h>
#include <string.h>
#include <limits.h>
#include <stdint.h>
#include <stdlib.h>
#include <sys/wait.h>
#include <signal.h>
#include <errno.h>
#include <fcntl.h>
#include "pthread_impl.h"
static void reap(pid_t pid)
{
int status;
while (waitpid(pid, &status, 0) < 0 && errno == EINTR);
}
static char *getword(FILE *f)
{
char *s = 0;
return getdelim(&s, (size_t [1]){0}, 0, f) < 0 ? 0 : s;
}
static int do_wordexp(const char *s, wordexp_t *we, int flags)
{
size_t i, l;
int sq=0, dq=0;
size_t np=0;
char *w, **tmp;
char *redir = (flags & WRDE_SHOWERR) ? "" : "2>/dev/null";
int err = 0;
FILE *f;
size_t wc = 0;
char **wv = 0;
int p[2];
pid_t pid;
sigset_t set;
if (flags & WRDE_REUSE) wordfree(we);
if (flags & WRDE_NOCMD) for (i=0; s[i]; i++) switch (s[i]) {
case '\\':
if (!sq && !s[++i]) return WRDE_SYNTAX;
break;
case '\'':
if (!dq) sq^=1;
break;
case '"':
if (!sq) dq^=1;
break;
case '(':
if (np) {
np++;
break;
}
case ')':
if (np) {
np--;
break;
}
case '\n':
case '|':
case '&':
case ';':
case '<':
case '>':
case '{':
case '}':
if (!(sq|dq|np)) return WRDE_BADCHAR;
break;
case '$':
if (sq) break;
if (s[i+1]=='(' && s[i+2]=='(') {
i += 2;
np += 2;
break;
} else if (s[i+1] != '(') break;
case '`':
if (sq) break;
return WRDE_CMDSUB;
}
if (flags & WRDE_APPEND) {
wc = we->we_wordc;
wv = we->we_wordv;
}
i = wc;
if (flags & WRDE_DOOFFS) {
if (we->we_offs > SIZE_MAX/sizeof(void *)/4)
goto nospace;
i += we->we_offs;
} else {
we->we_offs = 0;
}
if (pipe2(p, O_CLOEXEC) < 0) goto nospace;
__block_all_sigs(&set);
pid = fork();
__restore_sigs(&set);
if (pid < 0) {
close(p[0]);
close(p[1]);
goto nospace;
}
if (!pid) {
if (p[1] == 1) fcntl(1, F_SETFD, 0);
else dup2(p[1], 1);
execl("/bin/sh", "sh", "-c",
"eval \"printf %s\\\\\\\\0 x $1 $2\"",
"sh", s, redir, (char *)0);
_exit(1);
}
close(p[1]);
f = fdopen(p[0], "r");
if (!f) {
close(p[0]);
kill(pid, SIGKILL);
reap(pid);
goto nospace;
}
l = wv ? i+1 : 0;
free(getword(f));
if (feof(f)) {
fclose(f);
reap(pid);
return WRDE_SYNTAX;
}
while ((w = getword(f))) {
if (i+1 >= l) {
l += l/2+10;
tmp = realloc(wv, l*sizeof(char *));
if (!tmp) break;
wv = tmp;
}
wv[i++] = w;
wv[i] = 0;
}
if (!feof(f)) err = WRDE_NOSPACE;
fclose(f);
reap(pid);
if (!wv) wv = calloc(i+1, sizeof *wv);
we->we_wordv = wv;
we->we_wordc = i;
if (flags & WRDE_DOOFFS) {
if (wv) for (i=we->we_offs; i; i--)
we->we_wordv[i-1] = 0;
we->we_wordc -= we->we_offs;
}
return err;
nospace:
if (!(flags & WRDE_APPEND)) {
we->we_wordc = 0;
we->we_wordv = 0;
}
return WRDE_NOSPACE;
}
int wordexp(const char *restrict s, wordexp_t *restrict we, int flags)
{
int r, cs;
pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cs);
r = do_wordexp(s, we, flags);
pthread_setcancelstate(cs, 0);
return r;
}
void wordfree(wordexp_t *we)
{
size_t i;
if (!we->we_wordv) return;
for (i=0; i<we->we_wordc; i++) free(we->we_wordv[we->we_offs+i]);
free(we->we_wordv);
we->we_wordv = 0;
we->we_wordc = 0;
}
|