--- /dev/null
+#!./perl
+#
+# Test inheriting file descriptors across exec (close-on-exec).
+#
+# perlvar describes $^F aka $SYSTEM_FD_MAX as follows:
+#
+# The maximum system file descriptor, ordinarily 2. System file
+# descriptors are passed to exec()ed processes, while higher file
+# descriptors are not. Also, during an open(), system file descriptors
+# are preserved even if the open() fails. (Ordinary file descriptors
+# are closed before the open() is attempted.) The close-on-exec
+# status of a file descriptor will be decided according to the value of
+# C<$^F> when the corresponding file, pipe, or socket was opened, not
+# the time of the exec().
+#
+# This documented close-on-exec behaviour is typically implemented in
+# various places (e.g. pp_sys.c) with code something like:
+#
+# #if defined(HAS_FCNTL) && defined(F_SETFD)
+# fcntl(fd, F_SETFD, fd > PL_maxsysfd); /* ensure close-on-exec */
+# #endif
+#
+# This behaviour, therefore, is only currently implemented for platforms
+# where:
+#
+# a) HAS_FCNTL and F_SETFD are both defined
+# b) Integer fds are native OS handles
+#
+# ... which is typically just the Unix-like platforms.
+#
+# Notice that though integer fds are supported by the C runtime library
+# on Windows, they are not native OS handles, and so are not inherited
+# across an exec (though native Windows file handles are).
+
+BEGIN {
+ chdir 't' if -d 't';
+ @INC = '../lib';
+ use Config;
+ if (!$Config{'d_fcntl'}) {
+ print("1..0 # Skip: fcntl() is not available\n");
+ exit(0);
+ }
+ require './test.pl';
+}
+
+use strict;
+
+$|=1;
+
+my $Is_VMS = $^O eq 'VMS';
+my $Is_MacOS = $^O eq 'MacOS';
+my $Is_Win32 = $^O eq 'MSWin32';
+my $Is_Cygwin = $^O eq 'cygwin';
+
+# When in doubt, skip.
+skip_all("MacOS") if $Is_MacOS;
+skip_all("VMS") if $Is_VMS;
+skip_all("cygwin") if $Is_Cygwin;
+skip_all("Win32") if $Is_Win32;
+
+sub make_tmp_file {
+ my ($fname, $fcontents) = @_;
+ local *FHTMP;
+ open FHTMP, ">$fname" or die "open '$fname': $!";
+ print FHTMP $fcontents or die "print '$fname': $!";
+ close FHTMP or die "close '$fname': $!";
+}
+
+my $Perl = which_perl();
+my $quote = $Is_VMS || $Is_Win32 ? '"' : "'";
+
+my $tmperr = 'cloexece.tmp';
+my $tmpfile1 = 'cloexec1.tmp';
+my $tmpfile2 = 'cloexec2.tmp';
+my $tmpfile1_contents = "tmpfile1 line 1\ntmpfile1 line 2\n";
+my $tmpfile2_contents = "tmpfile2 line 1\ntmpfile2 line 2\n";
+make_tmp_file($tmpfile1, $tmpfile1_contents);
+make_tmp_file($tmpfile2, $tmpfile2_contents);
+
+# $Child_prog is the program run by the child that inherits the fd.
+# Note: avoid using ' or " in $Child_prog since it is run with -e
+my $Child_prog = <<'CHILD_PROG';
+my $fd = shift;
+print qq{childfd=$fd\n};
+open INHERIT, qq{<&=$fd} or die qq{open $fd: $!};
+my $line = <INHERIT>;
+close INHERIT or die qq{close $fd: $!};
+print $line
+CHILD_PROG
+$Child_prog =~ tr/\n//d;
+
+plan(tests => 29);
+
+sub test_not_inherited {
+ my $expected_fd = shift;
+ ok( -f $tmpfile2, "tmpfile '$tmpfile2' exists" );
+ local *FHPARENT2;
+ open FHPARENT2, "<$tmpfile2" or die "open '$tmpfile2': $!";
+ my $parentfd = fileno FHPARENT2;
+ defined $parentfd or die "fileno: $!";
+ cmp_ok( $parentfd, '==', $expected_fd, "parent open fd=$parentfd" );
+ my $cmd = qq{$Perl -e $quote$Child_prog$quote $parentfd};
+ # Expect 'Bad file descriptor' or similar to be written to STDERR.
+ local *SAVERR; open SAVERR, ">&STDERR"; # save original STDERR
+ open STDERR, ">$tmperr" or die "open '$tmperr': $!";
+ my $out = `$cmd`;
+ my $rc = $? >> 8;
+ open STDERR, ">&SAVERR" or die "error: restore STDERR: $!";
+ close SAVERR or die "error: close SAVERR: $!";
+ cmp_ok( $rc, '!=', 0,
+ "child return code=$rc (non-zero means cannot inherit fd=$parentfd)" );
+ cmp_ok( $out =~ tr/\n//, '==', 1, 'child stdout: has 1 newline' );
+ is( $out, "childfd=$expected_fd\n", 'child stdout: fd' );
+ close FHPARENT2 or die "close '$tmpfile2': $!";
+}
+
+sub test_inherited {
+ my $expected_fd = shift;
+ ok( -f $tmpfile1, "tmpfile '$tmpfile1' exists" );
+ local *FHPARENT1;
+ open FHPARENT1, "<$tmpfile1" or die "open-1 '$tmpfile1': $!";
+ my $parentfd = fileno FHPARENT1;
+ defined $parentfd or die "fileno: $!";
+ cmp_ok( $parentfd, '==', $expected_fd, "parent open fd=$parentfd" );
+ my $cmd = qq{$Perl -e $quote$Child_prog$quote $parentfd};
+ my $out = `$cmd`;
+ my $rc = $? >> 8;
+ cmp_ok( $rc, '==', 0,
+ "child return code=$rc (zero means inherited fd=$parentfd ok)" );
+ my @lines = split(/^/, $out);
+ cmp_ok( $out =~ tr/\n//, '==', 2, 'child stdout: has 2 newlines' );
+ cmp_ok( scalar(@lines), '==', 2, 'child stdout: split into 2 lines' );
+ is( $lines[0], "childfd=$expected_fd\n", 'child stdout: fd' );
+ is( $lines[1], "tmpfile1 line 1\n", 'child stdout: line 1' );
+ close FHPARENT1 or die "close '$tmpfile1': $!";
+}
+
+$^F == 2 or print STDERR "# warning: \$^F is $^F (not 2)\n";
+
+# Should not be able to inherit $^F+1 in the default case.
+test_not_inherited($^F+1);
+
+# Should be able to inherit $^F after incrementing it.
+++$^F;
+test_inherited($^F);
+# ... and test that you cannot inherit fd = $^F+1.
+open FHPARENT1, "<$tmpfile1" or die "open '$tmpfile1': $!";
+test_not_inherited($^F+1);
+close FHPARENT1 or die "close '$tmpfile1': $!";
+# ... and now you can inherit after incrementing.
+++$^F;
+open FHPARENT2, "<$tmpfile2" or die "open '$tmpfile2': $!";
+test_inherited($^F);
+close FHPARENT2 or die "close '$tmpfile2': $!";
+
+# Re-test default case after decrementing.
+--$^F; --$^F;
+test_not_inherited($^F+1);
+
+END {
+ defined $tmperr and unlink($tmperr);
+ defined $tmpfile1 and unlink($tmpfile1);
+ defined $tmpfile2 and unlink($tmpfile2);
+}
projects / p5sagit/p5-mst-13.2.git / commitdiff