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author | Lorry Tar Creator <lorry-tar-importer@lorry> | 2016-01-20 10:55:18 +0000 |
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committer | Lorry Tar Creator <lorry-tar-importer@lorry> | 2016-01-20 10:55:18 +0000 |
commit | 70e9163c9c18e995515598085cb824e554eb7ae7 (patch) | |
tree | a42dc8b2a6c031354bf31472de888bfc8a060132 /lib/cloexec.c | |
parent | cbf5993c43f49281173f185863577d86bfac6eae (diff) | |
download | coreutils-tarball-70e9163c9c18e995515598085cb824e554eb7ae7.tar.gz |
coreutils-8.25HEADcoreutils-8.25master
Diffstat (limited to 'lib/cloexec.c')
-rw-r--r-- | lib/cloexec.c | 60 |
1 files changed, 42 insertions, 18 deletions
diff --git a/lib/cloexec.c b/lib/cloexec.c index 6480006..1202836 100644 --- a/lib/cloexec.c +++ b/lib/cloexec.c @@ -1,11 +1,11 @@ /* closexec.c - set or clear the close-on-exec descriptor flag - Copyright (C) 1991, 2004, 2005, 2006 Free Software Foundation, Inc. + Copyright (C) 1991, 2004-2006, 2009-2016 Free Software Foundation, Inc. - This program is free software; you can redistribute it and/or modify + This program 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, or (at your option) - any later version. + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of @@ -13,8 +13,7 @@ GNU General Public License for more details. You should have received a copy of the GNU General Public License - along with this program; if not, write to the Free Software Foundation, - Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. + along with this program. If not, see <http://www.gnu.org/licenses/>. The code is taken from glibc/manual/llio.texi */ @@ -22,21 +21,24 @@ #include "cloexec.h" -#include <unistd.h> +#include <errno.h> #include <fcntl.h> +#include <unistd.h> -#ifndef FD_CLOEXEC -# define FD_CLOEXEC 1 -#endif - -/* Set the `FD_CLOEXEC' flag of DESC if VALUE is true, +/* Set the 'FD_CLOEXEC' flag of DESC if VALUE is true, or clear the flag if VALUE is false. - Return 0 on success, or -1 on error with `errno' set. */ + Return 0 on success, or -1 on error with 'errno' set. + + Note that on MingW, this function does NOT protect DESC from being + inherited into spawned children. Instead, either use dup_cloexec + followed by closing the original DESC, or use interfaces such as + open or pipe2 that accept flags like O_CLOEXEC to create DESC + non-inheritable in the first place. */ int set_cloexec_flag (int desc, bool value) { -#if defined F_GETFD && defined F_SETFD +#ifdef F_SETFD int flags = fcntl (desc, F_GETFD, 0); @@ -45,15 +47,37 @@ set_cloexec_flag (int desc, bool value) int newflags = (value ? flags | FD_CLOEXEC : flags & ~FD_CLOEXEC); if (flags == newflags - || fcntl (desc, F_SETFD, newflags) != -1) - return 0; + || fcntl (desc, F_SETFD, newflags) != -1) + return 0; } return -1; -#else +#else /* !F_SETFD */ + + /* Use dup2 to reject invalid file descriptors; the cloexec flag + will be unaffected. */ + if (desc < 0) + { + errno = EBADF; + return -1; + } + if (dup2 (desc, desc) < 0) + /* errno is EBADF here. */ + return -1; + /* There is nothing we can do on this kind of platform. Punt. */ return 0; +#endif /* !F_SETFD */ +} + -#endif +/* Duplicates a file handle FD, while marking the copy to be closed + prior to exec or spawn. Returns -1 and sets errno if FD could not + be duplicated. */ + +int +dup_cloexec (int fd) +{ + return fcntl (fd, F_DUPFD_CLOEXEC, 0); } |