[src/trunk]: src/bin/sh PR/48201: Miwa Susumu: Fix set -C (no clobber) for PO...

[christos <christos%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/7e23ef24b32a
branches:  trunk
changeset: 333034:7e23ef24b32a
user:      christos <christos%NetBSD.org@localhost>
date:      Wed Oct 15 14:54:25 2014 +0000

description:
PR/48201: Miwa Susumu: Fix set -C (no clobber) for POSIX; from FreeBSD
Can't use O_EXCL because of device nodes; also truncate.

diffstat:

 bin/sh/redir.c |  32 ++++++++++++++++++++++++++------
 1 files changed, 26 insertions(+), 6 deletions(-)

diffs (66 lines):

diff -r 30792550809f -r 7e23ef24b32a bin/sh/redir.c
--- a/bin/sh/redir.c    Wed Oct 15 09:05:46 2014 +0000
+++ b/bin/sh/redir.c    Wed Oct 15 14:54:25 2014 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: redir.c,v 1.35 2013/06/27 23:22:04 yamt Exp $  */
+/*     $NetBSD: redir.c,v 1.36 2014/10/15 14:54:25 christos Exp $      */
 
 /*-
  * Copyright (c) 1991, 1993
@@ -37,7 +37,7 @@
 #if 0
 static char sccsid[] = "@(#)redir.c    8.2 (Berkeley) 5/4/95";
 #else
-__RCSID("$NetBSD: redir.c,v 1.35 2013/06/27 23:22:04 yamt Exp $");
+__RCSID("$NetBSD: redir.c,v 1.36 2014/10/15 14:54:25 christos Exp $");
 #endif
 #endif /* not lint */
 
@@ -164,10 +164,11 @@
 STATIC void
 openredirect(union node *redir, char memory[10], int flags)
 {
+       struct stat sb;
        int fd = redir->nfile.fd;
        char *fname;
        int f;
-       int oflags = O_WRONLY|O_CREAT|O_TRUNC, eflags;
+       int eflags;
 
        /*
         * We suppress interrupts so that we won't leave open file
@@ -194,12 +195,31 @@
                        goto ecreate;
                break;
        case NTO:
-               if (Cflag)
-                       oflags |= O_EXCL;
+               if (Cflag) {
+                       fname = redir->nfile.expfname;
+                       if (stat(fname, &sb) == -1) {
+                               if ((f = open(fname, O_WRONLY|O_CREAT|O_EXCL,
+                                   0666)) < 0)
+                                       goto ecreate;
+                       } else if (!S_ISREG(sb.st_mode)) {
+                               if ((f = open(fname, O_WRONLY, 0666)) < 0)
+                                       goto ecreate;
+                               if (fstat(f, &sb) != -1 &&
+                                   S_ISREG(sb.st_mode)) {
+                                       close(f);
+                                       errno = EEXIST;
+                                       goto ecreate;
+                               }
+                       } else {
+                               errno = EEXIST;
+                               goto ecreate;
+                       }
+                       break;
+               }
                /* FALLTHROUGH */
        case NCLOBBER:
                fname = redir->nfile.expfname;
-               if ((f = open(fname, oflags, 0666)) < 0)
+               if ((f = open(fname, O_WRONLY|O_CREAT|O_TRUNC, 0666)) < 0)
                        goto ecreate;
                break;
        case NAPPEND: