diff options
Diffstat (limited to 'src/basic/fdset.c')
| -rw-r--r-- | src/basic/fdset.c | 285 |
1 files changed, 285 insertions, 0 deletions
diff --git a/src/basic/fdset.c b/src/basic/fdset.c new file mode 100644 index 0000000000..6101b628ec --- /dev/null +++ b/src/basic/fdset.c @@ -0,0 +1,285 @@ +/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ + +/*** + 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 Lesser General Public License as published by + the Free Software Foundation; either version 2.1 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 + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public License + along with systemd; If not, see <http://www.gnu.org/licenses/>. +***/ + +#include <errno.h> +#include <dirent.h> +#include <fcntl.h> + +#include "set.h" +#include "util.h" +#include "macro.h" +#include "fdset.h" +#include "sd-daemon.h" + +#define MAKE_SET(s) ((Set*) s) +#define MAKE_FDSET(s) ((FDSet*) s) + +/* Make sure we can distinguish 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(NULL)); +} + +int fdset_new_array(FDSet **ret, int *fds, unsigned n_fds) { + unsigned i; + FDSet *s; + int r; + + assert(ret); + + s = fdset_new(); + if (!s) + return -ENOMEM; + + for (i = 0; i < n_fds; i++) { + + r = fdset_put(s, fds[i]); + if (r < 0) { + set_free(MAKE_SET(s)); + return r; + } + } + + *ret = s; + return 0; +} + +FDSet* 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 */ + + /* When reloading duplicates of the private bus + * connection fds and suchlike are closed here, which + * has no effect at all, since they are only + * duplicates. So don't be surprised about these log + * messages. */ + + log_debug("Closing left-over fd %i", PTR_TO_FD(p)); + close_nointr(PTR_TO_FD(p)); + } + + set_free(MAKE_SET(s)); + return NULL; +} + +int fdset_put(FDSet *s, int fd) { + assert(s); + assert(fd >= 0); + + return set_put(MAKE_SET(s), FD_TO_PTR(fd)); +} + +int fdset_consume(FDSet *s, int fd) { + int r; + + assert(s); + assert(fd >= 0); + + r = fdset_put(s, fd); + if (r <= 0) + safe_close(fd); + + return r; +} + +int fdset_put_dup(FDSet *s, int fd) { + int copy, r; + + assert(s); + assert(fd >= 0); + + copy = fcntl(fd, F_DUPFD_CLOEXEC, 3); + if (copy < 0) + return -errno; + + r = fdset_put(s, copy); + if (r < 0) { + safe_close(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) { + _cleanup_closedir_ DIR *d = NULL; + struct dirent *de; + int r = 0; + FDSet *s; + + assert(_s); + + /* Creates an fdset and fills in all currently open file + * descriptors. */ + + d = opendir("/proc/self/fd"); + if (!d) + return -errno; + + s = fdset_new(); + if (!s) { + r = -ENOMEM; + goto finish; + } + + while ((de = readdir(d))) { + int fd = -1; + + if (hidden_file(de->d_name)) + continue; + + r = safe_atoi(de->d_name, &fd); + if (r < 0) + goto finish; + + if (fd < 3) + continue; + + if (fd == dirfd(d)) + continue; + + r = fdset_put(s, fd); + if (r < 0) + goto finish; + } + + r = 0; + *_s = s; + s = NULL; + +finish: + /* 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; +} + +int fdset_new_listen_fds(FDSet **_s, bool unset) { + int n, fd, r; + FDSet *s; + + assert(_s); + + /* Creates an fdset and fills in all passed file descriptors */ + + s = fdset_new(); + if (!s) { + r = -ENOMEM; + goto fail; + } + + n = sd_listen_fds(unset); + for (fd = SD_LISTEN_FDS_START; fd < SD_LISTEN_FDS_START + n; fd ++) { + r = fdset_put(s, fd); + if (r < 0) + goto fail; + } + + *_s = s; + return 0; + + +fail: + if (s) + set_free(MAKE_SET(s)); + + return r; +} + +int fdset_close_others(FDSet *fds) { + void *e; + Iterator i; + int *a; + unsigned j, m; + + j = 0, m = fdset_size(fds); + a = alloca(sizeof(int) * m); + SET_FOREACH(e, MAKE_SET(fds), i) + a[j++] = PTR_TO_FD(e); + + assert(j == m); + + return close_all_fds(a, j); +} + +unsigned fdset_size(FDSet *fds) { + return set_size(MAKE_SET(fds)); +} + +bool fdset_isempty(FDSet *fds) { + return set_isempty(MAKE_SET(fds)); +} + +int fdset_iterate(FDSet *s, Iterator *i) { + void *p; + + p = set_iterate(MAKE_SET(s), i); + if (!p) + return -ENOENT; + + return PTR_TO_FD(p); +} + +int fdset_steal_first(FDSet *fds) { + void *p; + + p = set_steal_first(MAKE_SET(fds)); + if (!p) + return -ENOENT; + + return PTR_TO_FD(p); +} |