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-rw-r--r--src/basic/fd-util.c380
1 files changed, 0 insertions, 380 deletions
diff --git a/src/basic/fd-util.c b/src/basic/fd-util.c
deleted file mode 100644
index 5c820332a5..0000000000
--- a/src/basic/fd-util.c
+++ /dev/null
@@ -1,380 +0,0 @@
-/***
- 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 <fcntl.h>
-#include <sys/resource.h>
-#include <sys/socket.h>
-#include <sys/stat.h>
-#include <unistd.h>
-
-#include "fd-util.h"
-#include "fs-util.h"
-#include "macro.h"
-#include "missing.h"
-#include "parse-util.h"
-#include "path-util.h"
-#include "socket-util.h"
-#include "stdio-util.h"
-#include "util.h"
-
-int close_nointr(int fd) {
- assert(fd >= 0);
-
- if (close(fd) >= 0)
- return 0;
-
- /*
- * Just ignore EINTR; a retry loop is the wrong thing to do on
- * Linux.
- *
- * http://lkml.indiana.edu/hypermail/linux/kernel/0509.1/0877.html
- * https://bugzilla.gnome.org/show_bug.cgi?id=682819
- * http://utcc.utoronto.ca/~cks/space/blog/unix/CloseEINTR
- * https://sites.google.com/site/michaelsafyan/software-engineering/checkforeintrwheninvokingclosethinkagain
- */
- if (errno == EINTR)
- return 0;
-
- return -errno;
-}
-
-int safe_close(int fd) {
-
- /*
- * Like close_nointr() but cannot fail. Guarantees errno is
- * unchanged. Is a NOP with negative fds passed, and returns
- * -1, so that it can be used in this syntax:
- *
- * fd = safe_close(fd);
- */
-
- if (fd >= 0) {
- PROTECT_ERRNO;
-
- /* The kernel might return pretty much any error code
- * via close(), but the fd will be closed anyway. The
- * only condition we want to check for here is whether
- * the fd was invalid at all... */
-
- assert_se(close_nointr(fd) != -EBADF);
- }
-
- return -1;
-}
-
-void safe_close_pair(int p[]) {
- assert(p);
-
- if (p[0] == p[1]) {
- /* Special case pairs which use the same fd in both
- * directions... */
- p[0] = p[1] = safe_close(p[0]);
- return;
- }
-
- p[0] = safe_close(p[0]);
- p[1] = safe_close(p[1]);
-}
-
-void close_many(const int fds[], unsigned n_fd) {
- unsigned i;
-
- assert(fds || n_fd <= 0);
-
- for (i = 0; i < n_fd; i++)
- safe_close(fds[i]);
-}
-
-int fclose_nointr(FILE *f) {
- assert(f);
-
- /* Same as close_nointr(), but for fclose() */
-
- if (fclose(f) == 0)
- return 0;
-
- if (errno == EINTR)
- return 0;
-
- return -errno;
-}
-
-FILE* safe_fclose(FILE *f) {
-
- /* Same as safe_close(), but for fclose() */
-
- if (f) {
- PROTECT_ERRNO;
-
- assert_se(fclose_nointr(f) != EBADF);
- }
-
- return NULL;
-}
-
-DIR* safe_closedir(DIR *d) {
-
- if (d) {
- PROTECT_ERRNO;
-
- assert_se(closedir(d) >= 0 || errno != EBADF);
- }
-
- return NULL;
-}
-
-int fd_nonblock(int fd, bool nonblock) {
- int flags, nflags;
-
- assert(fd >= 0);
-
- flags = fcntl(fd, F_GETFL, 0);
- if (flags < 0)
- return -errno;
-
- if (nonblock)
- nflags = flags | O_NONBLOCK;
- else
- nflags = flags & ~O_NONBLOCK;
-
- if (nflags == flags)
- return 0;
-
- if (fcntl(fd, F_SETFL, nflags) < 0)
- return -errno;
-
- return 0;
-}
-
-int fd_cloexec(int fd, bool cloexec) {
- int flags, nflags;
-
- assert(fd >= 0);
-
- flags = fcntl(fd, F_GETFD, 0);
- if (flags < 0)
- return -errno;
-
- if (cloexec)
- nflags = flags | FD_CLOEXEC;
- else
- nflags = flags & ~FD_CLOEXEC;
-
- if (nflags == flags)
- return 0;
-
- if (fcntl(fd, F_SETFD, nflags) < 0)
- return -errno;
-
- return 0;
-}
-
-void stdio_unset_cloexec(void) {
- fd_cloexec(STDIN_FILENO, false);
- fd_cloexec(STDOUT_FILENO, false);
- fd_cloexec(STDERR_FILENO, false);
-}
-
-_pure_ static bool fd_in_set(int fd, const int fdset[], unsigned n_fdset) {
- unsigned i;
-
- assert(n_fdset == 0 || fdset);
-
- for (i = 0; i < n_fdset; i++)
- if (fdset[i] == fd)
- return true;
-
- return false;
-}
-
-int close_all_fds(const int except[], unsigned n_except) {
- _cleanup_closedir_ DIR *d = NULL;
- struct dirent *de;
- int r = 0;
-
- assert(n_except == 0 || except);
-
- d = opendir("/proc/self/fd");
- if (!d) {
- int fd;
- struct rlimit rl;
-
- /* When /proc isn't available (for example in chroots)
- * the fallback is brute forcing through the fd
- * table */
-
- assert_se(getrlimit(RLIMIT_NOFILE, &rl) >= 0);
- for (fd = 3; fd < (int) rl.rlim_max; fd ++) {
-
- if (fd_in_set(fd, except, n_except))
- continue;
-
- if (close_nointr(fd) < 0)
- if (errno != EBADF && r == 0)
- r = -errno;
- }
-
- return r;
- }
-
- while ((de = readdir(d))) {
- int fd = -1;
-
- if (hidden_or_backup_file(de->d_name))
- continue;
-
- if (safe_atoi(de->d_name, &fd) < 0)
- /* Let's better ignore this, just in case */
- continue;
-
- if (fd < 3)
- continue;
-
- if (fd == dirfd(d))
- continue;
-
- if (fd_in_set(fd, except, n_except))
- continue;
-
- if (close_nointr(fd) < 0) {
- /* Valgrind has its own FD and doesn't want to have it closed */
- if (errno != EBADF && r == 0)
- r = -errno;
- }
- }
-
- return r;
-}
-
-int same_fd(int a, int b) {
- struct stat sta, stb;
- pid_t pid;
- int r, fa, fb;
-
- assert(a >= 0);
- assert(b >= 0);
-
- /* Compares two file descriptors. Note that semantics are
- * quite different depending on whether we have kcmp() or we
- * don't. If we have kcmp() this will only return true for
- * dup()ed file descriptors, but not otherwise. If we don't
- * have kcmp() this will also return true for two fds of the same
- * file, created by separate open() calls. Since we use this
- * call mostly for filtering out duplicates in the fd store
- * this difference hopefully doesn't matter too much. */
-
- if (a == b)
- return true;
-
- /* Try to use kcmp() if we have it. */
- pid = getpid();
- r = kcmp(pid, pid, KCMP_FILE, a, b);
- if (r == 0)
- return true;
- if (r > 0)
- return false;
- if (errno != ENOSYS)
- return -errno;
-
- /* We don't have kcmp(), use fstat() instead. */
- if (fstat(a, &sta) < 0)
- return -errno;
-
- if (fstat(b, &stb) < 0)
- return -errno;
-
- if ((sta.st_mode & S_IFMT) != (stb.st_mode & S_IFMT))
- return false;
-
- /* We consider all device fds different, since two device fds
- * might refer to quite different device contexts even though
- * they share the same inode and backing dev_t. */
-
- if (S_ISCHR(sta.st_mode) || S_ISBLK(sta.st_mode))
- return false;
-
- if (sta.st_dev != stb.st_dev || sta.st_ino != stb.st_ino)
- return false;
-
- /* The fds refer to the same inode on disk, let's also check
- * if they have the same fd flags. This is useful to
- * distinguish the read and write side of a pipe created with
- * pipe(). */
- fa = fcntl(a, F_GETFL);
- if (fa < 0)
- return -errno;
-
- fb = fcntl(b, F_GETFL);
- if (fb < 0)
- return -errno;
-
- return fa == fb;
-}
-
-void cmsg_close_all(struct msghdr *mh) {
- struct cmsghdr *cmsg;
-
- assert(mh);
-
- CMSG_FOREACH(cmsg, mh)
- if (cmsg->cmsg_level == SOL_SOCKET && cmsg->cmsg_type == SCM_RIGHTS)
- close_many((int*) CMSG_DATA(cmsg), (cmsg->cmsg_len - CMSG_LEN(0)) / sizeof(int));
-}
-
-bool fdname_is_valid(const char *s) {
- const char *p;
-
- /* Validates a name for $LISTEN_FDNAMES. We basically allow
- * everything ASCII that's not a control character. Also, as
- * special exception the ":" character is not allowed, as we
- * use that as field separator in $LISTEN_FDNAMES.
- *
- * Note that the empty string is explicitly allowed
- * here. However, we limit the length of the names to 255
- * characters. */
-
- if (!s)
- return false;
-
- for (p = s; *p; p++) {
- if (*p < ' ')
- return false;
- if (*p >= 127)
- return false;
- if (*p == ':')
- return false;
- }
-
- return p - s < 256;
-}
-
-int fd_get_path(int fd, char **ret) {
- char procfs_path[strlen("/proc/self/fd/") + DECIMAL_STR_MAX(int)];
- int r;
-
- xsprintf(procfs_path, "/proc/self/fd/%i", fd);
-
- r = readlink_malloc(procfs_path, ret);
-
- if (r == -ENOENT) /* If the file doesn't exist the fd is invalid */
- return -EBADF;
-
- return r;
-}