X-Git-Url: https://git.cworth.org/git?p=tar;a=blobdiff_plain;f=gnu%2Fcloexec.c;fp=gnu%2Fcloexec.c;h=4fb995e8b180e04ade9e1b649228805b5d301f68;hp=0000000000000000000000000000000000000000;hb=ee168310ec4227174ace489bf5f81f8c2f91cde0;hpb=22f1eb8bc17e5be72dd23d42d6aaa60196ac22e6
diff --git a/gnu/cloexec.c b/gnu/cloexec.c
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+/* -*- buffer-read-only: t -*- vi: set ro: */
+/* DO NOT EDIT! GENERATED AUTOMATICALLY! */
+/* closexec.c - set or clear the close-on-exec descriptor flag
+
+ Copyright (C) 1991, 2004-2006, 2009-2010 Free Software Foundation, Inc.
+
+ 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 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
+ 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 this program. If not, see .
+
+ The code is taken from glibc/manual/llio.texi */
+
+#include
+
+#include "cloexec.h"
+
+#include
+#include
+#include
+
+/* 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.
+
+ 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)
+{
+#ifdef F_SETFD
+
+ int flags = fcntl (desc, F_GETFD, 0);
+
+ if (0 <= flags)
+ {
+ int newflags = (value ? flags | FD_CLOEXEC : flags & ~FD_CLOEXEC);
+
+ if (flags == newflags
+ || fcntl (desc, F_SETFD, newflags) != -1)
+ return 0;
+ }
+
+ return -1;
+
+#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 */
+}
+
+
+/* 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);
+}