From 65a5162550f58047974793cdc8067a970b2435c0 Mon Sep 17 00:00:00 2001 From: matz Date: Fri, 13 Aug 1999 05:45:20 +0000 Subject: 1.4.0 git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@520 b2dd03c8-39d4-4d8f-98ff-823fe69b080e --- missing/dup2.c | 69 +++++++++++++++++++++++++++++++++++++++------------------- 1 file changed, 47 insertions(+), 22 deletions(-) (limited to 'missing/dup2.c') diff --git a/missing/dup2.c b/missing/dup2.c index c541149d4b..e7cc46f4c1 100644 --- a/missing/dup2.c +++ b/missing/dup2.c @@ -1,36 +1,61 @@ -/* - * Copyright (c) 1991, Larry Wall +/* + * Public domain dup2() lookalike + * by Curtis Jackson @ AT&T Technologies, Burlington, NC + * electronic address: burl!rcj * - * You may distribute under the terms of either the GNU General Public - * License or the Artistic License, as specified in the README file. + * dup2 performs the following functions: + * + * Check to make sure that fd1 is a valid open file descriptor. + * Check to see if fd2 is already open; if so, close it. + * Duplicate fd1 onto fd2; checking to make sure fd2 is a valid fd. + * Return fd2 if all went well; return BADEXIT otherwise. */ -#include "defines.h" +#include "config.h" -#if defined(HAVE_FCNTL) && defined(F_DUPFD) +#if defined(HAVE_FCNTL) # include #endif +#if !defined(HAVE_FCNTL) || !defined(F_DUPFD) +# include +#endif + +#define BADEXIT -1 + int -dup2(oldfd,newfd) -int oldfd; -int newfd; +dup2(fd1, fd2) +int fd1, fd2; { #if defined(HAVE_FCNTL) && defined(F_DUPFD) - close(newfd); - return fcntl(oldfd, F_DUPFD, newfd); + if (fd1 != fd2) { +#ifdef F_GETFL + if (fcntl(fd1, F_GETFL) < 0) + return BADEXIT; + if (fcntl(fd2, F_GETFL) >= 0) + close(fd2); +#else + close(fd2); +#endif + if (fcntl(fd1, F_DUPFD, fd2) < 0) + return BADEXIT; + } + return fd2; #else - int fdtmp[256]; - int fdx = 0; - int fd; + extern int errno; + int i, fd, fds[256]; - if (oldfd == newfd) - return 0; - close(newfd); - while ((fd = dup(oldfd)) != newfd) /* good enough for low fd's */ - fdtmp[fdx++] = fd; - while (fdx > 0) - close(fdtmp[--fdx]); - return 0; + if (fd1 == fd2) return 0; + close(fd2); + for (i=0; i<256; i++) { + fd = fds[i] = dup(fd1); + if (fd == fd2) break; + } + while (i) { + close(fds[i--]); + } + if (fd == fd2) return 0; + errno = EMFILE; + return BADEXIT; #endif } -- cgit v1.2.3