From 74da141e618ef99959d509cb2e7be35a348a39db Mon Sep 17 00:00:00 2001 From: Thomas Guyot-Sionnest Date: Wed, 7 Apr 2010 21:11:46 -0400 Subject: Sync with the latest Gnulib code (177f525) Signed-off-by: Thomas Guyot-Sionnest --- gl/dup2.c | 128 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 128 insertions(+) create mode 100644 gl/dup2.c (limited to 'gl/dup2.c') diff --git a/gl/dup2.c b/gl/dup2.c new file mode 100644 index 00000000..a4422bf3 --- /dev/null +++ b/gl/dup2.c @@ -0,0 +1,128 @@ +/* Duplicate an open file descriptor to a specified file descriptor. + + Copyright (C) 1999, 2004-2007, 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 . */ + +/* written by Paul Eggert */ + +#include + +/* Specification. */ +#include + +#include +#include + +#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__ +/* Get declarations of the Win32 API functions. */ +# define WIN32_LEAN_AND_MEAN +# include +#endif + +#if HAVE_DUP2 + +# undef dup2 + +int +rpl_dup2 (int fd, int desired_fd) +{ + int result; +# if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__ + /* If fd is closed, mingw hangs on dup2 (fd, fd). If fd is open, + dup2 (fd, fd) returns 0, but all further attempts to use fd in + future dup2 calls will hang. */ + if (fd == desired_fd) + { + if ((HANDLE) _get_osfhandle (fd) == INVALID_HANDLE_VALUE) + { + errno = EBADF; + return -1; + } + return fd; + } + /* Wine 1.0.1 return 0 when desired_fd is negative but not -1: + http://bugs.winehq.org/show_bug.cgi?id=21289 */ + if (desired_fd < 0) + { + errno = EBADF; + return -1; + } +# endif + result = dup2 (fd, desired_fd); +# ifdef __linux__ + /* Correct a Linux return value. + + */ + if (fd == desired_fd && result == (unsigned int) -EBADF) + { + errno = EBADF; + result = -1; + } +# endif + if (result == 0) + result = desired_fd; + /* Correct a cygwin 1.5.x errno value. */ + else if (result == -1 && errno == EMFILE) + errno = EBADF; +# if REPLACE_FCHDIR + if (fd != desired_fd && result != -1) + result = _gl_register_dup (fd, result); +# endif + return result; +} + +#else /* !HAVE_DUP2 */ + +/* On older platforms, dup2 did not exist. */ + +# ifndef F_DUPFD +static int +dupfd (int fd, int desired_fd) +{ + int duplicated_fd = dup (fd); + if (duplicated_fd < 0 || duplicated_fd == desired_fd) + return duplicated_fd; + else + { + int r = dupfd (fd, desired_fd); + int e = errno; + close (duplicated_fd); + errno = e; + return r; + } +} +# endif + +int +dup2 (int fd, int desired_fd) +{ + int result = fcntl (fd, F_GETFL) < 0 ? -1 : fd; + if (result == -1 || fd == desired_fd) + return result; + close (desired_fd); +# ifdef F_DUPFD + result = fcntl (fd, F_DUPFD, desired_fd); +# if REPLACE_FCHDIR + if (0 <= result) + result = _gl_register_dup (fd, result); +# endif +# else + result = dupfd (fd, desired_fd); +# endif + if (result == -1 && (errno == EMFILE || errno == EINVAL)) + errno = EBADF; + return result; +} +#endif /* !HAVE_DUP2 */ -- cgit v1.2.3-74-g34f1