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Set utf8 flag properly in localeconv
[perl5.git] / t / run / cloexec.t
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1#!./perl
2#
3# Test inheriting file descriptors across exec (close-on-exec).
4#
5# perlvar describes $^F aka $SYSTEM_FD_MAX as follows:
6#
7# The maximum system file descriptor, ordinarily 2. System file
8# descriptors are passed to exec()ed processes, while higher file
9# descriptors are not. Also, during an open(), system file descriptors
10# are preserved even if the open() fails. (Ordinary file descriptors
11# are closed before the open() is attempted.) The close-on-exec
12# status of a file descriptor will be decided according to the value of
13# C<$^F> when the corresponding file, pipe, or socket was opened, not
14# the time of the exec().
15#
16# This documented close-on-exec behaviour is typically implemented in
17# various places (e.g. pp_sys.c) with code something like:
18#
19# #if defined(HAS_FCNTL) && defined(F_SETFD)
20# fcntl(fd, F_SETFD, fd > PL_maxsysfd); /* ensure close-on-exec */
21# #endif
22#
23# This behaviour, therefore, is only currently implemented for platforms
24# where:
25#
26# a) HAS_FCNTL and F_SETFD are both defined
27# b) Integer fds are native OS handles
28#
29# ... which is typically just the Unix-like platforms.
30#
31# Notice that though integer fds are supported by the C runtime library
32# on Windows, they are not native OS handles, and so are not inherited
33# across an exec (though native Windows file handles are).
34
35BEGIN {
36 chdir 't' if -d 't';
37 @INC = '../lib';
742218b3 38 require './test.pl';
9c8416b2 39 skip_all_without_config('d_fcntl');
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40}
41
42use strict;
43
44$|=1;
45
742218b3 46# When in doubt, skip.
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47skip_all($^O)
48 if $^O eq 'VMS' or $^O eq 'MSWin32';
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49
50sub make_tmp_file {
51 my ($fname, $fcontents) = @_;
52 local *FHTMP;
53 open FHTMP, ">$fname" or die "open '$fname': $!";
54 print FHTMP $fcontents or die "print '$fname': $!";
55 close FHTMP or die "close '$fname': $!";
56}
57
58my $Perl = which_perl();
901455ec 59my $quote = "'";
742218b3 60
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61my $tmperr = tempfile();
62my $tmpfile1 = tempfile();
63my $tmpfile2 = tempfile();
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64my $tmpfile1_contents = "tmpfile1 line 1\ntmpfile1 line 2\n";
65my $tmpfile2_contents = "tmpfile2 line 1\ntmpfile2 line 2\n";
66make_tmp_file($tmpfile1, $tmpfile1_contents);
67make_tmp_file($tmpfile2, $tmpfile2_contents);
68
69# $Child_prog is the program run by the child that inherits the fd.
70# Note: avoid using ' or " in $Child_prog since it is run with -e
71my $Child_prog = <<'CHILD_PROG';
72my $fd = shift;
73print qq{childfd=$fd\n};
74open INHERIT, qq{<&=$fd} or die qq{open $fd: $!};
75my $line = <INHERIT>;
76close INHERIT or die qq{close $fd: $!};
77print $line
78CHILD_PROG
79$Child_prog =~ tr/\n//d;
80
dcb5c535 81plan(tests => 22);
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82
83sub test_not_inherited {
84 my $expected_fd = shift;
85 ok( -f $tmpfile2, "tmpfile '$tmpfile2' exists" );
dcb5c535 86 my $cmd = qq{$Perl -e $quote$Child_prog$quote $expected_fd};
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87 # Expect 'Bad file descriptor' or similar to be written to STDERR.
88 local *SAVERR; open SAVERR, ">&STDERR"; # save original STDERR
89 open STDERR, ">$tmperr" or die "open '$tmperr': $!";
90 my $out = `$cmd`;
91 my $rc = $? >> 8;
92 open STDERR, ">&SAVERR" or die "error: restore STDERR: $!";
93 close SAVERR or die "error: close SAVERR: $!";
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94 # XXX: it seems one cannot rely on a non-zero return code,
95 # at least not on Tru64.
96 # cmp_ok( $rc, '!=', 0,
97 # "child return code=$rc (non-zero means cannot inherit fd=$expected_fd)" );
98 cmp_ok( $out =~ tr/\n//, '==', 1,
99 "child stdout: has 1 newline (rc=$rc, should be non-zero)" );
742218b3 100 is( $out, "childfd=$expected_fd\n", 'child stdout: fd' );
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101}
102
103sub test_inherited {
104 my $expected_fd = shift;
105 ok( -f $tmpfile1, "tmpfile '$tmpfile1' exists" );
dcb5c535 106 my $cmd = qq{$Perl -e $quote$Child_prog$quote $expected_fd};
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107 my $out = `$cmd`;
108 my $rc = $? >> 8;
109 cmp_ok( $rc, '==', 0,
dcb5c535 110 "child return code=$rc (zero means inherited fd=$expected_fd ok)" );
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111 my @lines = split(/^/, $out);
112 cmp_ok( $out =~ tr/\n//, '==', 2, 'child stdout: has 2 newlines' );
113 cmp_ok( scalar(@lines), '==', 2, 'child stdout: split into 2 lines' );
114 is( $lines[0], "childfd=$expected_fd\n", 'child stdout: fd' );
115 is( $lines[1], "tmpfile1 line 1\n", 'child stdout: line 1' );
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116}
117
118$^F == 2 or print STDERR "# warning: \$^F is $^F (not 2)\n";
119
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120# Should not be able to inherit > $^F in the default case.
121open FHPARENT2, "<$tmpfile2" or die "open '$tmpfile2': $!";
122my $parentfd2 = fileno FHPARENT2;
123defined $parentfd2 or die "fileno: $!";
124cmp_ok( $parentfd2, '>', $^F, "parent open fd=$parentfd2 (\$^F=$^F)" );
125test_not_inherited($parentfd2);
126close FHPARENT2 or die "close '$tmpfile2': $!";
127
128# Should be able to inherit $^F after setting to $parentfd2
129# Need to set $^F before open because close-on-exec set at time of open.
130$^F = $parentfd2;
131open FHPARENT1, "<$tmpfile1" or die "open '$tmpfile1': $!";
132my $parentfd1 = fileno FHPARENT1;
133defined $parentfd1 or die "fileno: $!";
134cmp_ok( $parentfd1, '<=', $^F, "parent open fd=$parentfd1 (\$^F=$^F)" );
135test_inherited($parentfd1);
136close FHPARENT1 or die "close '$tmpfile1': $!";
742218b3 137
c7fb9cc8 138# ... and test that you cannot inherit fd = $^F+n.
742218b3 139open FHPARENT1, "<$tmpfile1" or die "open '$tmpfile1': $!";
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140open FHPARENT2, "<$tmpfile2" or die "open '$tmpfile2': $!";
141$parentfd2 = fileno FHPARENT2;
142defined $parentfd2 or die "fileno: $!";
143cmp_ok( $parentfd2, '>', $^F, "parent open fd=$parentfd2 (\$^F=$^F)" );
144test_not_inherited($parentfd2);
145close FHPARENT2 or die "close '$tmpfile2': $!";
742218b3 146close FHPARENT1 or die "close '$tmpfile1': $!";
dcb5c535 147
742218b3 148# ... and now you can inherit after incrementing.
c7fb9cc8 149$^F = $parentfd2;
742218b3 150open FHPARENT2, "<$tmpfile2" or die "open '$tmpfile2': $!";
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151open FHPARENT1, "<$tmpfile1" or die "open '$tmpfile1': $!";
152$parentfd1 = fileno FHPARENT1;
153defined $parentfd1 or die "fileno: $!";
154cmp_ok( $parentfd1, '<=', $^F, "parent open fd=$parentfd1 (\$^F=$^F)" );
155test_inherited($parentfd1);
156close FHPARENT1 or die "close '$tmpfile1': $!";
742218b3 157close FHPARENT2 or die "close '$tmpfile2': $!";