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For C:/lo/libo-master/solenv/bin/make_installer.pl
  Run on Mon Sep 24 00:52:54 2012
Reported on Mon Sep 24 07:34:51 2012

Filename/usr/lib/perl5/5.14/filetest.pm
StatementsExecuted 5 statements in 29µs
Subroutines
Calls P F Exclusive
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Subroutine
1118µs8µsfiletest::::importfiletest::import
0000s0sfiletest::::unimportfiletest::unimport
Call graph for these subroutines as a Graphviz dot language file.
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Code
1package filetest;
2
312µsour $VERSION = '1.02';
4
5=head1 NAME
6
7filetest - Perl pragma to control the filetest permission operators
8
9=head1 SYNOPSIS
10
11 $can_perhaps_read = -r "file"; # use the mode bits
12 {
13 use filetest 'access'; # intuit harder
14 $can_really_read = -r "file";
15 }
16 $can_perhaps_read = -r "file"; # use the mode bits again
17
18=head1 DESCRIPTION
19
20This pragma tells the compiler to change the behaviour of the filetest
21permission operators, C<-r> C<-w> C<-x> C<-R> C<-W> C<-X>
22(see L<perlfunc>).
23
24The default behaviour of file test operators is to use the simple
25mode bits as returned by the stat() family of system calls. However,
26many operating systems have additional features to define more complex
27access rights, for example ACLs (Access Control Lists).
28For such environments, C<use filetest> may help the permission
29operators to return results more consistent with other tools.
30
31The C<use filetest> or C<no filetest> statements affect file tests defined in
32their block, up to the end of the closest enclosing block (they are lexically
33block-scoped).
34
35Currently, only the C<access> sub-pragma is implemented. It enables (or
36disables) the use of access() when available, that is, on most UNIX systems and
37other POSIX environments. See details below.
38
39=head2 Consider this carefully
40
41The stat() mode bits are probably right for most of the files and
42directories found on your system, because few people want to use the
43additional features offered by access(). But you may encounter surprises
44if your program runs on a system that uses ACLs, since the stat()
45information won't reflect the actual permissions.
46
47There may be a slight performance decrease in the filetest operations
48when the filetest pragma is in effect, because checking bits is very
49cheap.
50
51Also, note that using the file tests for security purposes is a lost cause
52from the start: there is a window open for race conditions (who is to
53say that the permissions will not change between the test and the real
54operation?). Therefore if you are serious about security, just try
55the real operation and test for its success - think in terms of atomic
56operations. Filetests are more useful for filesystem administrative
57tasks, when you have no need for the content of the elements on disk.
58
59=head2 The "access" sub-pragma
60
61UNIX and POSIX systems provide an abstract access() operating system call,
62which should be used to query the read, write, and execute rights. This
63function hides various distinct approaches in additional operating system
64specific security features, like Access Control Lists (ACLs)
65
66The extended filetest functionality is used by Perl only when the argument
67of the operators is a filename, not when it is a filehandle.
68
69=head2 Limitation with regard to C<_>
70
71Because access() does not invoke stat() (at least not in a way visible
72to Perl), B<the stat result cache "_" is not set>. This means that the
73outcome of the following two tests is different. The first has the stat
74bits of C</etc/passwd> in C<_>, and in the second case this still
75contains the bits of C</etc>.
76
77 { -d '/etc';
78 -w '/etc/passwd';
79 print -f _ ? 'Yes' : 'No'; # Yes
80 }
81
82 { use filetest 'access';
83 -d '/etc';
84 -w '/etc/passwd';
85 print -f _ ? 'Yes' : 'No'; # No
86 }
87
88Of course, unless your OS does not implement access(), in which case the
89pragma is simply ignored. Best not to use C<_> at all in a file where
90the filetest pragma is active!
91
92As a side effect, as C<_> doesn't work, stacked filetest operators
93(C<-f -w $file>) won't work either.
94
95This limitation might be removed in a future version of perl.
96
97=cut
98
991500ns$filetest::hint_bits = 0x00400000; # HINT_FILETEST_ACCESS
100
101
# spent 8µs within filetest::import which was called: # once (8µs+0s) by installer::download::BEGIN@42 at line 45 of /cygdrive/c/lo/libo-master/instsetoo_native/util/C:/lo/libo-master/solenv/bin/modules/installer/download.pm
sub import {
102111µs if ( $_[1] eq 'access' ) {
10313µs $^H |= $filetest::hint_bits;
104 } else {
105 die "filetest: the only implemented subpragma is 'access'.\n";
106 }
107}
108
109sub unimport {
110 if ( $_[1] eq 'access' ) {
111 $^H &= ~$filetest::hint_bits;
112 } else {
113 die "filetest: the only implemented subpragma is 'access'.\n";
114 }
115}
116
117112µs1;