From 42409c4069deb2417b838a49810ecbce306a72b9 Mon Sep 17 00:00:00 2001
From: Father Chrysostomos <sprout@cpan.org>
Date: Wed, 25 Jul 2012 22:04:02 -0700
Subject: [PATCH] Stop truncate(word) from falling back to file name
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In commit 5e0adc2d66, which was a bug fix, I made the mistake of
checking the truth of the return value of gv_fetchsv, which is called
when truncate’s argument is a bareword.

This meant that truncate FOO, 0; would truncate the file named FOO if
the glob happened to have been deleted.
---
 pp_sys.c  |  6 +++---
 t/io/fs.t | 12 ++++++++++--
 2 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/pp_sys.c b/pp_sys.c
index 76bd1ac..a17227d4 100644
--- a/pp_sys.c
+++ b/pp_sys.c
@@ -2215,9 +2215,9 @@ PP(pp_truncate)
 	GV *tmpgv;
 	IO *io;
 
-	if ((tmpgv = PL_op->op_flags & OPf_SPECIAL
-	               ? gv_fetchsv(sv, 0, SVt_PVIO)
-	               : MAYBE_DEREF_GV(sv) )) {
+	if (PL_op->op_flags & OPf_SPECIAL
+	               ? (tmpgv = gv_fetchsv(sv, 0, SVt_PVIO), 1)
+	               : !!(tmpgv = MAYBE_DEREF_GV(sv)) ) {
 	    io = GvIO(tmpgv);
 	    if (!io)
 		result = 0;
diff --git a/t/io/fs.t b/t/io/fs.t
index 1cdddec..26208c1 100644
--- a/t/io/fs.t
+++ b/t/io/fs.t
@@ -46,7 +46,7 @@ $needs_fh_reopen = 1 if (defined &Win32::IsWin95 && Win32::IsWin95());
 my $skip_mode_checks =
     $^O eq 'cygwin' && $ENV{CYGWIN} !~ /ntsec/;
 
-plan tests => 51;
+plan tests => 52;
 
 my $tmpdir = tempfile();
 my $tmpdir1 = tempfile();
@@ -372,7 +372,7 @@ SKIP: {
 
     SKIP: {
         if ($^O eq 'vos') {
-	    skip ("# TODO - hit VOS bug posix-973 - cannot resize an open file below the current file pos.", 5);
+	    skip ("# TODO - hit VOS bug posix-973 - cannot resize an open file below the current file pos.", 6);
 	}
 
 	is(-s $tmpfile, 200, "fh resize to 200 working (filename check)");
@@ -407,6 +407,14 @@ SKIP: {
 	is(-s $tmpfile, 100, "fh resize by IO slot working");
 
 	close FH;
+
+	my $n = "for_fs_dot_t$$";
+	open FH, ">$n" or die "open $n: $!";
+	print FH "bloh blah bla\n";
+	close FH or die "close $n: $!";
+	eval "truncate $n, 0; 1" or die;
+	ok !-z $n, 'truncate(word) does not fall back to file name';
+	unlink $n;
     }
 }
 
-- 
1.8.3.1