systemd/fdset.c
2010-04-21 03:27:44 +02:00

163 lines
3.8 KiB
C

/*-*- Mode: C; c-basic-offset: 8 -*-*/
/***
This file is part of systemd.
Copyright 2010 Lennart Poettering
systemd is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
systemd is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.
You should have received a copy of the GNU General Public License
along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
#include <errno.h>
#include <dirent.h>
#include <fcntl.h>
#include <unistd.h>
#include "set.h"
#include "util.h"
#include "macro.h"
#include "fdset.h"
#define MAKE_SET(s) ((Set*) s)
#define MAKE_FDSET(s) ((FDSet*) s)
/* Make sure we can distuingish fd 0 and NULL */
#define FD_TO_PTR(fd) INT_TO_PTR((fd)+1)
#define PTR_TO_FD(p) (PTR_TO_INT(p)-1)
FDSet *fdset_new(void) {
return MAKE_FDSET(set_new(trivial_hash_func, trivial_compare_func));
}
void fdset_free(FDSet *s) {
void *p;
while ((p = set_steal_first(MAKE_SET(s)))) {
/* Valgrind's fd might have ended up in this set here,
* due to fdset_new_fill(). We'll ignore all failures
* here, so that the EBADFD that valgrind will return
* us on close() doesn't influence us */
log_warning("Closing left-over fd %i", PTR_TO_FD(p));
close_nointr(PTR_TO_FD(p));
}
set_free(MAKE_SET(s));
}
int fdset_put(FDSet *s, int fd) {
assert(s);
assert(fd >= 0);
return set_put(MAKE_SET(s), FD_TO_PTR(fd));
}
int fdset_put_dup(FDSet *s, int fd) {
int copy, r;
assert(s);
assert(fd >= 0);
if ((copy = fcntl(fd, F_DUPFD_CLOEXEC, 3)) < 0)
return -errno;
if ((r = fdset_put(s, copy)) < 0) {
close_nointr_nofail(copy);
return r;
}
return copy;
}
bool fdset_contains(FDSet *s, int fd) {
assert(s);
assert(fd >= 0);
return !!set_get(MAKE_SET(s), FD_TO_PTR(fd));
}
int fdset_remove(FDSet *s, int fd) {
assert(s);
assert(fd >= 0);
return set_remove(MAKE_SET(s), FD_TO_PTR(fd)) ? fd : -ENOENT;
}
int fdset_new_fill(FDSet **_s) {
DIR *d;
struct dirent *de;
int r = 0;
FDSet *s;
assert(_s);
/* Creates an fdsets and fills in all currently open file
* descriptors. */
if (!(d = opendir("/proc/self/fd")))
return -errno;
if (!(s = fdset_new())) {
r = -ENOMEM;
goto finish;
}
while ((de = readdir(d))) {
int fd = -1;
if (ignore_file(de->d_name))
continue;
if ((r = safe_atoi(de->d_name, &fd)) < 0)
goto finish;
if (fd < 3)
continue;
if (fd == dirfd(d))
continue;
if ((r = fdset_put(s, fd)) < 0)
goto finish;
}
r = 0;
*_s = s;
s = NULL;
finish:
closedir(d);
/* We won't close the fds here! */
if (s)
set_free(MAKE_SET(s));
return r;
}
int fdset_cloexec(FDSet *fds, bool b) {
Iterator i;
void *p;
int r;
assert(fds);
SET_FOREACH(p, MAKE_SET(fds), i)
if ((r = fd_cloexec(PTR_TO_FD(p), b)) < 0)
return r;
return 0;
}