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package File::Temp; # git description: v0.2310-3-gc7148fe | |
# ABSTRACT: return name and handle of a temporary file safely | |
our $VERSION = '0.2311'; | |
#pod =begin :__INTERNALS | |
#pod | |
#pod =head1 PORTABILITY | |
#pod | |
#pod This section is at the top in order to provide easier access to | |
#pod porters. It is not expected to be rendered by a standard pod | |
#pod formatting tool. Please skip straight to the SYNOPSIS section if you | |
#pod are not trying to port this module to a new platform. | |
#pod | |
#pod This module is designed to be portable across operating systems and it | |
#pod currently supports Unix, VMS, DOS, OS/2, Windows and Mac OS | |
#pod (Classic). When porting to a new OS there are generally three main | |
#pod issues that have to be solved: | |
#pod | |
#pod =over 4 | |
#pod | |
#pod =item * | |
#pod | |
#pod Can the OS unlink an open file? If it can not then the | |
#pod C<_can_unlink_opened_file> method should be modified. | |
#pod | |
#pod =item * | |
#pod | |
#pod Are the return values from C<stat> reliable? By default all the | |
#pod return values from C<stat> are compared when unlinking a temporary | |
#pod file using the filename and the handle. Operating systems other than | |
#pod unix do not always have valid entries in all fields. If utility function | |
#pod C<File::Temp::unlink0> fails then the C<stat> comparison should be | |
#pod modified accordingly. | |
#pod | |
#pod =item * | |
#pod | |
#pod Security. Systems that can not support a test for the sticky bit | |
#pod on a directory can not use the MEDIUM and HIGH security tests. | |
#pod The C<_can_do_level> method should be modified accordingly. | |
#pod | |
#pod =back | |
#pod | |
#pod =end :__INTERNALS | |
#pod | |
#pod =head1 SYNOPSIS | |
#pod | |
#pod use File::Temp qw/ tempfile tempdir /; | |
#pod | |
#pod $fh = tempfile(); | |
#pod ($fh, $filename) = tempfile(); | |
#pod | |
#pod ($fh, $filename) = tempfile( $template, DIR => $dir); | |
#pod ($fh, $filename) = tempfile( $template, SUFFIX => '.dat'); | |
#pod ($fh, $filename) = tempfile( $template, TMPDIR => 1 ); | |
#pod | |
#pod binmode( $fh, ":utf8" ); | |
#pod | |
#pod $dir = tempdir( CLEANUP => 1 ); | |
#pod ($fh, $filename) = tempfile( DIR => $dir ); | |
#pod | |
#pod Object interface: | |
#pod | |
#pod require File::Temp; | |
#pod use File::Temp (); | |
#pod use File::Temp qw/ :seekable /; | |
#pod | |
#pod $fh = File::Temp->new(); | |
#pod $fname = $fh->filename; | |
#pod | |
#pod $fh = File::Temp->new(TEMPLATE => $template); | |
#pod $fname = $fh->filename; | |
#pod | |
#pod $tmp = File::Temp->new( UNLINK => 0, SUFFIX => '.dat' ); | |
#pod print $tmp "Some data\n"; | |
#pod print "Filename is $tmp\n"; | |
#pod $tmp->seek( 0, SEEK_END ); | |
#pod | |
#pod $dir = File::Temp->newdir(); # CLEANUP => 1 by default | |
#pod | |
#pod The following interfaces are provided for compatibility with | |
#pod existing APIs. They should not be used in new code. | |
#pod | |
#pod MkTemp family: | |
#pod | |
#pod use File::Temp qw/ :mktemp /; | |
#pod | |
#pod ($fh, $file) = mkstemp( "tmpfileXXXXX" ); | |
#pod ($fh, $file) = mkstemps( "tmpfileXXXXXX", $suffix); | |
#pod | |
#pod $tmpdir = mkdtemp( $template ); | |
#pod | |
#pod $unopened_file = mktemp( $template ); | |
#pod | |
#pod POSIX functions: | |
#pod | |
#pod use File::Temp qw/ :POSIX /; | |
#pod | |
#pod $file = tmpnam(); | |
#pod $fh = tmpfile(); | |
#pod | |
#pod ($fh, $file) = tmpnam(); | |
#pod | |
#pod Compatibility functions: | |
#pod | |
#pod $unopened_file = File::Temp::tempnam( $dir, $pfx ); | |
#pod | |
#pod =head1 DESCRIPTION | |
#pod | |
#pod C<File::Temp> can be used to create and open temporary files in a safe | |
#pod way. There is both a function interface and an object-oriented | |
#pod interface. The File::Temp constructor or the tempfile() function can | |
#pod be used to return the name and the open filehandle of a temporary | |
#pod file. The tempdir() function can be used to create a temporary | |
#pod directory. | |
#pod | |
#pod The security aspect of temporary file creation is emphasized such that | |
#pod a filehandle and filename are returned together. This helps guarantee | |
#pod that a race condition can not occur where the temporary file is | |
#pod created by another process between checking for the existence of the | |
#pod file and its opening. Additional security levels are provided to | |
#pod check, for example, that the sticky bit is set on world writable | |
#pod directories. See L<"safe_level"> for more information. | |
#pod | |
#pod For compatibility with popular C library functions, Perl implementations of | |
#pod the mkstemp() family of functions are provided. These are, mkstemp(), | |
#pod mkstemps(), mkdtemp() and mktemp(). | |
#pod | |
#pod Additionally, implementations of the standard L<POSIX|POSIX> | |
#pod tmpnam() and tmpfile() functions are provided if required. | |
#pod | |
#pod Implementations of mktemp(), tmpnam(), and tempnam() are provided, | |
#pod but should be used with caution since they return only a filename | |
#pod that was valid when function was called, so cannot guarantee | |
#pod that the file will not exist by the time the caller opens the filename. | |
#pod | |
#pod Filehandles returned by these functions support the seekable methods. | |
#pod | |
#pod =cut | |
# Toolchain targets v5.8.1, but we'll try to support back to v5.6 anyway. | |
# It might be possible to make this v5.5, but many v5.6isms are creeping | |
# into the code and tests. | |
use 5.006; | |
use strict; | |
use Carp; | |
use File::Spec 0.8; | |
use Cwd (); | |
use File::Path 2.06 qw/ rmtree /; | |
use Fcntl 1.03; | |
use IO::Seekable; # For SEEK_* | |
use Errno; | |
use Scalar::Util 'refaddr'; | |
require VMS::Stdio if $^O eq 'VMS'; | |
# pre-emptively load Carp::Heavy. If we don't when we run out of file | |
# handles and attempt to call croak() we get an error message telling | |
# us that Carp::Heavy won't load rather than an error telling us we | |
# have run out of file handles. We either preload croak() or we | |
# switch the calls to croak from _gettemp() to use die. | |
eval { require Carp::Heavy; }; | |
# Need the Symbol package if we are running older perl | |
require Symbol if $] < 5.006; | |
### For the OO interface | |
use parent 0.221 qw/ IO::Handle IO::Seekable /; | |
use overload '""' => "STRINGIFY", '0+' => "NUMIFY", | |
fallback => 1; | |
our $DEBUG = 0; | |
our $KEEP_ALL = 0; | |
# We are exporting functions | |
use Exporter 5.57 'import'; # 5.57 lets us import 'import' | |
# Export list - to allow fine tuning of export table | |
our @EXPORT_OK = qw{ | |
tempfile | |
tempdir | |
tmpnam | |
tmpfile | |
mktemp | |
mkstemp | |
mkstemps | |
mkdtemp | |
unlink0 | |
cleanup | |
SEEK_SET | |
SEEK_CUR | |
SEEK_END | |
}; | |
# Groups of functions for export | |
our %EXPORT_TAGS = ( | |
'POSIX' => [qw/ tmpnam tmpfile /], | |
'mktemp' => [qw/ mktemp mkstemp mkstemps mkdtemp/], | |
'seekable' => [qw/ SEEK_SET SEEK_CUR SEEK_END /], | |
); | |
# add contents of these tags to @EXPORT | |
Exporter::export_tags('POSIX','mktemp','seekable'); | |
# This is a list of characters that can be used in random filenames | |
my @CHARS = (qw/ A B C D E F G H I J K L M N O P Q R S T U V W X Y Z | |
a b c d e f g h i j k l m n o p q r s t u v w x y z | |
0 1 2 3 4 5 6 7 8 9 _ | |
/); | |
# Maximum number of tries to make a temp file before failing | |
use constant MAX_TRIES => 1000; | |
# Minimum number of X characters that should be in a template | |
use constant MINX => 4; | |
# Default template when no template supplied | |
use constant TEMPXXX => 'X' x 10; | |
# Constants for the security level | |
use constant STANDARD => 0; | |
use constant MEDIUM => 1; | |
use constant HIGH => 2; | |
# OPENFLAGS. If we defined the flag to use with Sysopen here this gives | |
# us an optimisation when many temporary files are requested | |
my $OPENFLAGS = O_CREAT | O_EXCL | O_RDWR; | |
my $LOCKFLAG; | |
unless ($^O eq 'MacOS') { | |
for my $oflag (qw/ NOFOLLOW BINARY LARGEFILE NOINHERIT /) { | |
my ($bit, $func) = (0, "Fcntl::O_" . $oflag); | |
no strict 'refs'; | |
$OPENFLAGS |= $bit if eval { | |
# Make sure that redefined die handlers do not cause problems | |
# e.g. CGI::Carp | |
local $SIG{__DIE__} = sub {}; | |
local $SIG{__WARN__} = sub {}; | |
$bit = &$func(); | |
1; | |
}; | |
} | |
# Special case O_EXLOCK | |
$LOCKFLAG = eval { | |
local $SIG{__DIE__} = sub {}; | |
local $SIG{__WARN__} = sub {}; | |
&Fcntl::O_EXLOCK(); | |
}; | |
} | |
# On some systems the O_TEMPORARY flag can be used to tell the OS | |
# to automatically remove the file when it is closed. This is fine | |
# in most cases but not if tempfile is called with UNLINK=>0 and | |
# the filename is requested -- in the case where the filename is to | |
# be passed to another routine. This happens on windows. We overcome | |
# this by using a second open flags variable | |
my $OPENTEMPFLAGS = $OPENFLAGS; | |
unless ($^O eq 'MacOS') { | |
for my $oflag (qw/ TEMPORARY /) { | |
my ($bit, $func) = (0, "Fcntl::O_" . $oflag); | |
local($@); | |
no strict 'refs'; | |
$OPENTEMPFLAGS |= $bit if eval { | |
# Make sure that redefined die handlers do not cause problems | |
# e.g. CGI::Carp | |
local $SIG{__DIE__} = sub {}; | |
local $SIG{__WARN__} = sub {}; | |
$bit = &$func(); | |
1; | |
}; | |
} | |
} | |
# Private hash tracking which files have been created by each process id via the OO interface | |
my %FILES_CREATED_BY_OBJECT; | |
# INTERNAL ROUTINES - not to be used outside of package | |
# Generic routine for getting a temporary filename | |
# modelled on OpenBSD _gettemp() in mktemp.c | |
# The template must contain X's that are to be replaced | |
# with the random values | |
# Arguments: | |
# TEMPLATE - string containing the XXXXX's that is converted | |
# to a random filename and opened if required | |
# Optionally, a hash can also be supplied containing specific options | |
# "open" => if true open the temp file, else just return the name | |
# default is 0 | |
# "mkdir"=> if true, we are creating a temp directory rather than tempfile | |
# default is 0 | |
# "suffixlen" => number of characters at end of PATH to be ignored. | |
# default is 0. | |
# "unlink_on_close" => indicates that, if possible, the OS should remove | |
# the file as soon as it is closed. Usually indicates | |
# use of the O_TEMPORARY flag to sysopen. | |
# Usually irrelevant on unix | |
# "use_exlock" => Indicates that O_EXLOCK should be used. Default is false. | |
# "file_permissions" => file permissions for sysopen(). Default is 0600. | |
# Optionally a reference to a scalar can be passed into the function | |
# On error this will be used to store the reason for the error | |
# "ErrStr" => \$errstr | |
# "open" and "mkdir" can not both be true | |
# "unlink_on_close" is not used when "mkdir" is true. | |
# The default options are equivalent to mktemp(). | |
# Returns: | |
# filehandle - open file handle (if called with doopen=1, else undef) | |
# temp name - name of the temp file or directory | |
# For example: | |
# ($fh, $name) = _gettemp($template, "open" => 1); | |
# for the current version, failures are associated with | |
# stored in an error string and returned to give the reason whilst debugging | |
# This routine is not called by any external function | |
sub _gettemp { | |
croak 'Usage: ($fh, $name) = _gettemp($template, OPTIONS);' | |
unless scalar(@_) >= 1; | |
# the internal error string - expect it to be overridden | |
# Need this in case the caller decides not to supply us a value | |
# need an anonymous scalar | |
my $tempErrStr; | |
# Default options | |
my %options = ( | |
"open" => 0, | |
"mkdir" => 0, | |
"suffixlen" => 0, | |
"unlink_on_close" => 0, | |
"use_exlock" => 0, | |
"ErrStr" => \$tempErrStr, | |
"file_permissions" => undef, | |
); | |
# Read the template | |
my $template = shift; | |
if (ref($template)) { | |
# Use a warning here since we have not yet merged ErrStr | |
carp "File::Temp::_gettemp: template must not be a reference"; | |
return (); | |
} | |
# Check that the number of entries on stack are even | |
if (scalar(@_) % 2 != 0) { | |
# Use a warning here since we have not yet merged ErrStr | |
carp "File::Temp::_gettemp: Must have even number of options"; | |
return (); | |
} | |
# Read the options and merge with defaults | |
%options = (%options, @_) if @_; | |
# Make sure the error string is set to undef | |
${$options{ErrStr}} = undef; | |
# Can not open the file and make a directory in a single call | |
if ($options{"open"} && $options{"mkdir"}) { | |
${$options{ErrStr}} = "doopen and domkdir can not both be true\n"; | |
return (); | |
} | |
# Find the start of the end of the Xs (position of last X) | |
# Substr starts from 0 | |
my $start = length($template) - 1 - $options{"suffixlen"}; | |
# Check that we have at least MINX x X (e.g. 'XXXX") at the end of the string | |
# (taking suffixlen into account). Any fewer is insecure. | |
# Do it using substr - no reason to use a pattern match since | |
# we know where we are looking and what we are looking for | |
if (substr($template, $start - MINX + 1, MINX) ne 'X' x MINX) { | |
${$options{ErrStr}} = "The template must end with at least ". | |
MINX . " 'X' characters\n"; | |
return (); | |
} | |
# Replace all the X at the end of the substring with a | |
# random character or just all the XX at the end of a full string. | |
# Do it as an if, since the suffix adjusts which section to replace | |
# and suffixlen=0 returns nothing if used in the substr directly | |
# and generate a full path from the template | |
my $path = _replace_XX($template, $options{"suffixlen"}); | |
# Split the path into constituent parts - eventually we need to check | |
# whether the directory exists | |
# We need to know whether we are making a temp directory | |
# or a tempfile | |
my ($volume, $directories, $file); | |
my $parent; # parent directory | |
if ($options{"mkdir"}) { | |
# There is no filename at the end | |
($volume, $directories, $file) = File::Spec->splitpath( $path, 1); | |
# The parent is then $directories without the last directory | |
# Split the directory and put it back together again | |
my @dirs = File::Spec->splitdir($directories); | |
# If @dirs only has one entry (i.e. the directory template) that means | |
# we are in the current directory | |
if ($#dirs == 0) { | |
$parent = File::Spec->curdir; | |
} else { | |
if ($^O eq 'VMS') { # need volume to avoid relative dir spec | |
$parent = File::Spec->catdir($volume, @dirs[0..$#dirs-1]); | |
$parent = 'sys$disk:[]' if $parent eq ''; | |
} else { | |
# Put it back together without the last one | |
$parent = File::Spec->catdir(@dirs[0..$#dirs-1]); | |
# ...and attach the volume (no filename) | |
$parent = File::Spec->catpath($volume, $parent, ''); | |
} | |
} | |
} else { | |
# Get rid of the last filename (use File::Basename for this?) | |
($volume, $directories, $file) = File::Spec->splitpath( $path ); | |
# Join up without the file part | |
$parent = File::Spec->catpath($volume,$directories,''); | |
# If $parent is empty replace with curdir | |
$parent = File::Spec->curdir | |
unless $directories ne ''; | |
} | |
# Check that the parent directories exist | |
# Do this even for the case where we are simply returning a name | |
# not a file -- no point returning a name that includes a directory | |
# that does not exist or is not writable | |
unless (-e $parent) { | |
${$options{ErrStr}} = "Parent directory ($parent) does not exist"; | |
return (); | |
} | |
unless (-d $parent) { | |
${$options{ErrStr}} = "Parent directory ($parent) is not a directory"; | |
return (); | |
} | |
# Check the stickiness of the directory and chown giveaway if required | |
# If the directory is world writable the sticky bit | |
# must be set | |
if (File::Temp->safe_level == MEDIUM) { | |
my $safeerr; | |
unless (_is_safe($parent,\$safeerr)) { | |
${$options{ErrStr}} = "Parent directory ($parent) is not safe ($safeerr)"; | |
return (); | |
} | |
} elsif (File::Temp->safe_level == HIGH) { | |
my $safeerr; | |
unless (_is_verysafe($parent, \$safeerr)) { | |
${$options{ErrStr}} = "Parent directory ($parent) is not safe ($safeerr)"; | |
return (); | |
} | |
} | |
my $perms = $options{file_permissions}; | |
my $has_perms = defined $perms; | |
$perms = 0600 unless $has_perms; | |
# Now try MAX_TRIES time to open the file | |
for (my $i = 0; $i < MAX_TRIES; $i++) { | |
# Try to open the file if requested | |
if ($options{"open"}) { | |
my $fh; | |
# If we are running before perl5.6.0 we can not auto-vivify | |
if ($] < 5.006) { | |
$fh = &Symbol::gensym; | |
} | |
# Try to make sure this will be marked close-on-exec | |
# XXX: Win32 doesn't respect this, nor the proper fcntl, | |
# but may have O_NOINHERIT. This may or may not be in Fcntl. | |
local $^F = 2; | |
# Attempt to open the file | |
my $open_success = undef; | |
if ( $^O eq 'VMS' and $options{"unlink_on_close"} && !$KEEP_ALL) { | |
# make it auto delete on close by setting FAB$V_DLT bit | |
$fh = VMS::Stdio::vmssysopen($path, $OPENFLAGS, $perms, 'fop=dlt'); | |
$open_success = $fh; | |
} else { | |
my $flags = ( ($options{"unlink_on_close"} && !$KEEP_ALL) ? | |
$OPENTEMPFLAGS : | |
$OPENFLAGS ); | |
$flags |= $LOCKFLAG if (defined $LOCKFLAG && $options{use_exlock}); | |
$open_success = sysopen($fh, $path, $flags, $perms); | |
} | |
if ( $open_success ) { | |
# in case of odd umask force rw | |
chmod($perms, $path) unless $has_perms; | |
# Opened successfully - return file handle and name | |
return ($fh, $path); | |
} else { | |
# Error opening file - abort with error | |
# if the reason was anything but EEXIST | |
unless ($!{EEXIST}) { | |
${$options{ErrStr}} = "Could not create temp file $path: $!"; | |
return (); | |
} | |
# Loop round for another try | |
} | |
} elsif ($options{"mkdir"}) { | |
# Open the temp directory | |
if (mkdir( $path, 0700)) { | |
# in case of odd umask | |
chmod(0700, $path); | |
return undef, $path; | |
} else { | |
# Abort with error if the reason for failure was anything | |
# except EEXIST | |
unless ($!{EEXIST}) { | |
${$options{ErrStr}} = "Could not create directory $path: $!"; | |
return (); | |
} | |
# Loop round for another try | |
} | |
} else { | |
# Return true if the file can not be found | |
# Directory has been checked previously | |
return (undef, $path) unless -e $path; | |
# Try again until MAX_TRIES | |
} | |
# Did not successfully open the tempfile/dir | |
# so try again with a different set of random letters | |
# No point in trying to increment unless we have only | |
# 1 X say and the randomness could come up with the same | |
# file MAX_TRIES in a row. | |
# Store current attempt - in principle this implies that the | |
# 3rd time around the open attempt that the first temp file | |
# name could be generated again. Probably should store each | |
# attempt and make sure that none are repeated | |
my $original = $path; | |
my $counter = 0; # Stop infinite loop | |
my $MAX_GUESS = 50; | |
do { | |
# Generate new name from original template | |
$path = _replace_XX($template, $options{"suffixlen"}); | |
$counter++; | |
} until ($path ne $original || $counter > $MAX_GUESS); | |
# Check for out of control looping | |
if ($counter > $MAX_GUESS) { | |
${$options{ErrStr}} = "Tried to get a new temp name different to the previous value $MAX_GUESS times.\nSomething wrong with template?? ($template)"; | |
return (); | |
} | |
} | |
# If we get here, we have run out of tries | |
${ $options{ErrStr} } = "Have exceeded the maximum number of attempts (" | |
. MAX_TRIES . ") to open temp file/dir"; | |
return (); | |
} | |
# Internal routine to replace the XXXX... with random characters | |
# This has to be done by _gettemp() every time it fails to | |
# open a temp file/dir | |
# Arguments: $template (the template with XXX), | |
# $ignore (number of characters at end to ignore) | |
# Returns: modified template | |
sub _replace_XX { | |
croak 'Usage: _replace_XX($template, $ignore)' | |
unless scalar(@_) == 2; | |
my ($path, $ignore) = @_; | |
# Do it as an if, since the suffix adjusts which section to replace | |
# and suffixlen=0 returns nothing if used in the substr directly | |
# Alternatively, could simply set $ignore to length($path)-1 | |
# Don't want to always use substr when not required though. | |
my $end = ( $] >= 5.006 ? "\\z" : "\\Z" ); | |
if ($ignore) { | |
substr($path, 0, - $ignore) =~ s/X(?=X*$end)/$CHARS[ int( rand( @CHARS ) ) ]/ge; | |
} else { | |
$path =~ s/X(?=X*$end)/$CHARS[ int( rand( @CHARS ) ) ]/ge; | |
} | |
return $path; | |
} | |
# Internal routine to force a temp file to be writable after | |
# it is created so that we can unlink it. Windows seems to occasionally | |
# force a file to be readonly when written to certain temp locations | |
sub _force_writable { | |
my $file = shift; | |
chmod 0600, $file; | |
} | |
# internal routine to check to see if the directory is safe | |
# First checks to see if the directory is not owned by the | |
# current user or root. Then checks to see if anyone else | |
# can write to the directory and if so, checks to see if | |
# it has the sticky bit set | |
# Will not work on systems that do not support sticky bit | |
#Args: directory path to check | |
# Optionally: reference to scalar to contain error message | |
# Returns true if the path is safe and false otherwise. | |
# Returns undef if can not even run stat() on the path | |
# This routine based on version written by Tom Christiansen | |
# Presumably, by the time we actually attempt to create the | |
# file or directory in this directory, it may not be safe | |
# anymore... Have to run _is_safe directly after the open. | |
sub _is_safe { | |
my $path = shift; | |
my $err_ref = shift; | |
# Stat path | |
my @info = stat($path); | |
unless (scalar(@info)) { | |
$$err_ref = "stat(path) returned no values"; | |
return 0; | |
} | |
; | |
return 1 if $^O eq 'VMS'; # owner delete control at file level | |
# Check to see whether owner is neither superuser (or a system uid) nor me | |
# Use the effective uid from the $> variable | |
# UID is in [4] | |
if ($info[4] > File::Temp->top_system_uid() && $info[4] != $>) { | |
Carp::cluck(sprintf "uid=$info[4] topuid=%s euid=$> path='$path'", | |
File::Temp->top_system_uid()); | |
$$err_ref = "Directory owned neither by root nor the current user" | |
if ref($err_ref); | |
return 0; | |
} | |
# check whether group or other can write file | |
# use 066 to detect either reading or writing | |
# use 022 to check writability | |
# Do it with S_IWOTH and S_IWGRP for portability (maybe) | |
# mode is in info[2] | |
if (($info[2] & &Fcntl::S_IWGRP) || # Is group writable? | |
($info[2] & &Fcntl::S_IWOTH) ) { # Is world writable? | |
# Must be a directory | |
unless (-d $path) { | |
$$err_ref = "Path ($path) is not a directory" | |
if ref($err_ref); | |
return 0; | |
} | |
# Must have sticky bit set | |
unless (-k $path) { | |
$$err_ref = "Sticky bit not set on $path when dir is group|world writable" | |
if ref($err_ref); | |
return 0; | |
} | |
} | |
return 1; | |
} | |
# Internal routine to check whether a directory is safe | |
# for temp files. Safer than _is_safe since it checks for | |
# the possibility of chown giveaway and if that is a possibility | |
# checks each directory in the path to see if it is safe (with _is_safe) | |
# If _PC_CHOWN_RESTRICTED is not set, does the full test of each | |
# directory anyway. | |
# Takes optional second arg as scalar ref to error reason | |
sub _is_verysafe { | |
# Need POSIX - but only want to bother if really necessary due to overhead | |
require POSIX; | |
my $path = shift; | |
print "_is_verysafe testing $path\n" if $DEBUG; | |
return 1 if $^O eq 'VMS'; # owner delete control at file level | |
my $err_ref = shift; | |
# Should Get the value of _PC_CHOWN_RESTRICTED if it is defined | |
# and If it is not there do the extensive test | |
local($@); | |
my $chown_restricted; | |
$chown_restricted = &POSIX::_PC_CHOWN_RESTRICTED() | |
if eval { &POSIX::_PC_CHOWN_RESTRICTED(); 1}; | |
# If chown_resticted is set to some value we should test it | |
if (defined $chown_restricted) { | |
# Return if the current directory is safe | |
return _is_safe($path,$err_ref) if POSIX::sysconf( $chown_restricted ); | |
} | |
# To reach this point either, the _PC_CHOWN_RESTRICTED symbol | |
# was not available or the symbol was there but chown giveaway | |
# is allowed. Either way, we now have to test the entire tree for | |
# safety. | |
# Convert path to an absolute directory if required | |
unless (File::Spec->file_name_is_absolute($path)) { | |
$path = File::Spec->rel2abs($path); | |
} | |
# Split directory into components - assume no file | |
my ($volume, $directories, undef) = File::Spec->splitpath( $path, 1); | |
# Slightly less efficient than having a function in File::Spec | |
# to chop off the end of a directory or even a function that | |
# can handle ../ in a directory tree | |
# Sometimes splitdir() returns a blank at the end | |
# so we will probably check the bottom directory twice in some cases | |
my @dirs = File::Spec->splitdir($directories); | |
# Concatenate one less directory each time around | |
foreach my $pos (0.. $#dirs) { | |
# Get a directory name | |
my $dir = File::Spec->catpath($volume, | |
File::Spec->catdir(@dirs[0.. $#dirs - $pos]), | |
'' | |
); | |
print "TESTING DIR $dir\n" if $DEBUG; | |
# Check the directory | |
return 0 unless _is_safe($dir,$err_ref); | |
} | |
return 1; | |
} | |
# internal routine to determine whether unlink works on this | |
# platform for files that are currently open. | |
# Returns true if we can, false otherwise. | |
# Currently WinNT, OS/2 and VMS can not unlink an opened file | |
# On VMS this is because the O_EXCL flag is used to open the | |
# temporary file. Currently I do not know enough about the issues | |
# on VMS to decide whether O_EXCL is a requirement. | |
sub _can_unlink_opened_file { | |
if (grep $^O eq $_, qw/MSWin32 os2 VMS dos MacOS haiku/) { | |
return 0; | |
} else { | |
return 1; | |
} | |
} | |
# internal routine to decide which security levels are allowed | |
# see safe_level() for more information on this | |
# Controls whether the supplied security level is allowed | |
# $cando = _can_do_level( $level ) | |
sub _can_do_level { | |
# Get security level | |
my $level = shift; | |
# Always have to be able to do STANDARD | |
return 1 if $level == STANDARD; | |
# Currently, the systems that can do HIGH or MEDIUM are identical | |
if ( $^O eq 'MSWin32' || $^O eq 'os2' || $^O eq 'cygwin' || $^O eq 'dos' || $^O eq 'MacOS' || $^O eq 'mpeix') { | |
return 0; | |
} else { | |
return 1; | |
} | |
} | |
# This routine sets up a deferred unlinking of a specified | |
# filename and filehandle. It is used in the following cases: | |
# - Called by unlink0 if an opened file can not be unlinked | |
# - Called by tempfile() if files are to be removed on shutdown | |
# - Called by tempdir() if directories are to be removed on shutdown | |
# Arguments: | |
# _deferred_unlink( $fh, $fname, $isdir ); | |
# | |
# - filehandle (so that it can be explicitly closed if open | |
# - filename (the thing we want to remove) | |
# - isdir (flag to indicate that we are being given a directory) | |
# [and hence no filehandle] | |
# Status is not referred to since all the magic is done with an END block | |
{ | |
# Will set up two lexical variables to contain all the files to be | |
# removed. One array for files, another for directories They will | |
# only exist in this block. | |
# This means we only have to set up a single END block to remove | |
# all files. | |
# in order to prevent child processes inadvertently deleting the parent | |
# temp files we use a hash to store the temp files and directories | |
# created by a particular process id. | |
# %files_to_unlink contains values that are references to an array of | |
# array references containing the filehandle and filename associated with | |
# the temp file. | |
my (%files_to_unlink, %dirs_to_unlink); | |
# Set up an end block to use these arrays | |
END { | |
local($., $@, $!, $^E, $?); | |
cleanup(at_exit => 1); | |
} | |
# Cleanup function. Always triggered on END (with at_exit => 1) but | |
# can be invoked manually. | |
sub cleanup { | |
my %h = @_; | |
my $at_exit = delete $h{at_exit}; | |
$at_exit = 0 if not defined $at_exit; | |
{ my @k = sort keys %h; die "unrecognized parameters: @k" if @k } | |
if (!$KEEP_ALL) { | |
# Files | |
my @files = (exists $files_to_unlink{$$} ? | |
@{ $files_to_unlink{$$} } : () ); | |
foreach my $file (@files) { | |
# close the filehandle without checking its state | |
# in order to make real sure that this is closed | |
# if its already closed then I don't care about the answer | |
# probably a better way to do this | |
close($file->[0]); # file handle is [0] | |
if (-f $file->[1]) { # file name is [1] | |
_force_writable( $file->[1] ); # for windows | |
unlink $file->[1] or warn "Error removing ".$file->[1]; | |
} | |
} | |
# Dirs | |
my @dirs = (exists $dirs_to_unlink{$$} ? | |
@{ $dirs_to_unlink{$$} } : () ); | |
my ($cwd, $cwd_to_remove); | |
foreach my $dir (@dirs) { | |
if (-d $dir) { | |
# Some versions of rmtree will abort if you attempt to remove | |
# the directory you are sitting in. For automatic cleanup | |
# at program exit, we avoid this by chdir()ing out of the way | |
# first. If not at program exit, it's best not to mess with the | |
# current directory, so just let it fail with a warning. | |
if ($at_exit) { | |
$cwd = Cwd::abs_path(File::Spec->curdir) if not defined $cwd; | |
my $abs = Cwd::abs_path($dir); | |
if ($abs eq $cwd) { | |
$cwd_to_remove = $dir; | |
next; | |
} | |
} | |
eval { rmtree($dir, $DEBUG, 0); }; | |
warn $@ if ($@ && $^W); | |
} | |
} | |
if (defined $cwd_to_remove) { | |
# We do need to clean up the current directory, and everything | |
# else is done, so get out of there and remove it. | |
chdir $cwd_to_remove or die "cannot chdir to $cwd_to_remove: $!"; | |
my $updir = File::Spec->updir; | |
chdir $updir or die "cannot chdir to $updir: $!"; | |
eval { rmtree($cwd_to_remove, $DEBUG, 0); }; | |
warn $@ if ($@ && $^W); | |
} | |
# clear the arrays | |
@{ $files_to_unlink{$$} } = () | |
if exists $files_to_unlink{$$}; | |
@{ $dirs_to_unlink{$$} } = () | |
if exists $dirs_to_unlink{$$}; | |
} | |
} | |
# This is the sub called to register a file for deferred unlinking | |
# This could simply store the input parameters and defer everything | |
# until the END block. For now we do a bit of checking at this | |
# point in order to make sure that (1) we have a file/dir to delete | |
# and (2) we have been called with the correct arguments. | |
sub _deferred_unlink { | |
croak 'Usage: _deferred_unlink($fh, $fname, $isdir)' | |
unless scalar(@_) == 3; | |
my ($fh, $fname, $isdir) = @_; | |
warn "Setting up deferred removal of $fname\n" | |
if $DEBUG; | |
# make sure we save the absolute path for later cleanup | |
# OK to untaint because we only ever use this internally | |
# as a file path, never interpolating into the shell | |
$fname = Cwd::abs_path($fname); | |
($fname) = $fname =~ /^(.*)$/; | |
# If we have a directory, check that it is a directory | |
if ($isdir) { | |
if (-d $fname) { | |
# Directory exists so store it | |
# first on VMS turn []foo into [.foo] for rmtree | |
$fname = VMS::Filespec::vmspath($fname) if $^O eq 'VMS'; | |
$dirs_to_unlink{$$} = [] | |
unless exists $dirs_to_unlink{$$}; | |
push (@{ $dirs_to_unlink{$$} }, $fname); | |
} else { | |
carp "Request to remove directory $fname could not be completed since it does not exist!\n" if $^W; | |
} | |
} else { | |
if (-f $fname) { | |
# file exists so store handle and name for later removal | |
$files_to_unlink{$$} = [] | |
unless exists $files_to_unlink{$$}; | |
push(@{ $files_to_unlink{$$} }, [$fh, $fname]); | |
} else { | |
carp "Request to remove file $fname could not be completed since it is not there!\n" if $^W; | |
} | |
} | |
} | |
} | |
# normalize argument keys to upper case and do consistent handling | |
# of leading template vs TEMPLATE | |
sub _parse_args { | |
my $leading_template = (scalar(@_) % 2 == 1 ? shift(@_) : '' ); | |
my %args = @_; | |
%args = map +(uc($_) => $args{$_}), keys %args; | |
# template (store it in an array so that it will | |
# disappear from the arg list of tempfile) | |
my @template = ( | |
exists $args{TEMPLATE} ? $args{TEMPLATE} : | |
$leading_template ? $leading_template : () | |
); | |
delete $args{TEMPLATE}; | |
return( \@template, \%args ); | |
} | |
#pod =head1 OBJECT-ORIENTED INTERFACE | |
#pod | |
#pod This is the primary interface for interacting with | |
#pod C<File::Temp>. Using the OO interface a temporary file can be created | |
#pod when the object is constructed and the file can be removed when the | |
#pod object is no longer required. | |
#pod | |
#pod Note that there is no method to obtain the filehandle from the | |
#pod C<File::Temp> object. The object itself acts as a filehandle. The object | |
#pod isa C<IO::Handle> and isa C<IO::Seekable> so all those methods are | |
#pod available. | |
#pod | |
#pod Also, the object is configured such that it stringifies to the name of the | |
#pod temporary file and so can be compared to a filename directly. It numifies | |
#pod to the C<refaddr> the same as other handles and so can be compared to other | |
#pod handles with C<==>. | |
#pod | |
#pod $fh eq $filename # as a string | |
#pod $fh != \*STDOUT # as a number | |
#pod | |
#pod Available since 0.14. | |
#pod | |
#pod =over 4 | |
#pod | |
#pod =item B<new> | |
#pod | |
#pod Create a temporary file object. | |
#pod | |
#pod my $tmp = File::Temp->new(); | |
#pod | |
#pod by default the object is constructed as if C<tempfile> | |
#pod was called without options, but with the additional behaviour | |
#pod that the temporary file is removed by the object destructor | |
#pod if UNLINK is set to true (the default). | |
#pod | |
#pod Supported arguments are the same as for C<tempfile>: UNLINK | |
#pod (defaulting to true), DIR, EXLOCK, PERMS and SUFFIX. | |
#pod Additionally, the filename | |
#pod template is specified using the TEMPLATE option. The OPEN option | |
#pod is not supported (the file is always opened). | |
#pod | |
#pod $tmp = File::Temp->new( TEMPLATE => 'tempXXXXX', | |
#pod DIR => 'mydir', | |
#pod SUFFIX => '.dat'); | |
#pod | |
#pod Arguments are case insensitive. | |
#pod | |
#pod Can call croak() if an error occurs. | |
#pod | |
#pod Available since 0.14. | |
#pod | |
#pod TEMPLATE available since 0.23 | |
#pod | |
#pod =cut | |
sub new { | |
my $proto = shift; | |
my $class = ref($proto) || $proto; | |
my ($maybe_template, $args) = _parse_args(@_); | |
# see if they are unlinking (defaulting to yes) | |
my $unlink = (exists $args->{UNLINK} ? $args->{UNLINK} : 1 ); | |
delete $args->{UNLINK}; | |
# Protect OPEN | |
delete $args->{OPEN}; | |
# Open the file and retain file handle and file name | |
my ($fh, $path) = tempfile( @$maybe_template, %$args ); | |
print "Tmp: $fh - $path\n" if $DEBUG; | |
# Store the filename in the scalar slot | |
${*$fh} = $path; | |
# Cache the filename by pid so that the destructor can decide whether to remove it | |
$FILES_CREATED_BY_OBJECT{$$}{$path} = 1; | |
# Store unlink information in hash slot (plus other constructor info) | |
%{*$fh} = %$args; | |
# create the object | |
bless $fh, $class; | |
# final method-based configuration | |
$fh->unlink_on_destroy( $unlink ); | |
return $fh; | |
} | |
#pod =item B<newdir> | |
#pod | |
#pod Create a temporary directory using an object oriented interface. | |
#pod | |
#pod $dir = File::Temp->newdir(); | |
#pod | |
#pod By default the directory is deleted when the object goes out of scope. | |
#pod | |
#pod Supports the same options as the C<tempdir> function. Note that directories | |
#pod created with this method default to CLEANUP => 1. | |
#pod | |
#pod $dir = File::Temp->newdir( $template, %options ); | |
#pod | |
#pod A template may be specified either with a leading template or | |
#pod with a TEMPLATE argument. | |
#pod | |
#pod Available since 0.19. | |
#pod | |
#pod TEMPLATE available since 0.23. | |
#pod | |
#pod =cut | |
sub newdir { | |
my $self = shift; | |
my ($maybe_template, $args) = _parse_args(@_); | |
# handle CLEANUP without passing CLEANUP to tempdir | |
my $cleanup = (exists $args->{CLEANUP} ? $args->{CLEANUP} : 1 ); | |
delete $args->{CLEANUP}; | |
my $tempdir = tempdir( @$maybe_template, %$args); | |
# get a safe absolute path for cleanup, just like | |
# happens in _deferred_unlink | |
my $real_dir = Cwd::abs_path( $tempdir ); | |
($real_dir) = $real_dir =~ /^(.*)$/; | |
return bless { DIRNAME => $tempdir, | |
REALNAME => $real_dir, | |
CLEANUP => $cleanup, | |
LAUNCHPID => $$, | |
}, "File::Temp::Dir"; | |
} | |
#pod =item B<filename> | |
#pod | |
#pod Return the name of the temporary file associated with this object | |
#pod (if the object was created using the "new" constructor). | |
#pod | |
#pod $filename = $tmp->filename; | |
#pod | |
#pod This method is called automatically when the object is used as | |
#pod a string. | |
#pod | |
#pod Current API available since 0.14 | |
#pod | |
#pod =cut | |
sub filename { | |
my $self = shift; | |
return ${*$self}; | |
} | |
sub STRINGIFY { | |
my $self = shift; | |
return $self->filename; | |
} | |
# For reference, can't use '0+'=>\&Scalar::Util::refaddr directly because | |
# refaddr() demands one parameter only, whereas overload.pm calls with three | |
# even for unary operations like '0+'. | |
sub NUMIFY { | |
return refaddr($_[0]); | |
} | |
#pod =item B<dirname> | |
#pod | |
#pod Return the name of the temporary directory associated with this | |
#pod object (if the object was created using the "newdir" constructor). | |
#pod | |
#pod $dirname = $tmpdir->dirname; | |
#pod | |
#pod This method is called automatically when the object is used in string context. | |
#pod | |
#pod =item B<unlink_on_destroy> | |
#pod | |
#pod Control whether the file is unlinked when the object goes out of scope. | |
#pod The file is removed if this value is true and $KEEP_ALL is not. | |
#pod | |
#pod $fh->unlink_on_destroy( 1 ); | |
#pod | |
#pod Default is for the file to be removed. | |
#pod | |
#pod Current API available since 0.15 | |
#pod | |
#pod =cut | |
sub unlink_on_destroy { | |
my $self = shift; | |
if (@_) { | |
${*$self}{UNLINK} = shift; | |
} | |
return ${*$self}{UNLINK}; | |
} | |
#pod =item B<DESTROY> | |
#pod | |
#pod When the object goes out of scope, the destructor is called. This | |
#pod destructor will attempt to unlink the file (using L<unlink1|"unlink1">) | |
#pod if the constructor was called with UNLINK set to 1 (the default state | |
#pod if UNLINK is not specified). | |
#pod | |
#pod No error is given if the unlink fails. | |
#pod | |
#pod If the object has been passed to a child process during a fork, the | |
#pod file will be deleted when the object goes out of scope in the parent. | |
#pod | |
#pod For a temporary directory object the directory will be removed unless | |
#pod the CLEANUP argument was used in the constructor (and set to false) or | |
#pod C<unlink_on_destroy> was modified after creation. Note that if a temp | |
#pod directory is your current directory, it cannot be removed - a warning | |
#pod will be given in this case. C<chdir()> out of the directory before | |
#pod letting the object go out of scope. | |
#pod | |
#pod If the global variable $KEEP_ALL is true, the file or directory | |
#pod will not be removed. | |
#pod | |
#pod =cut | |
sub DESTROY { | |
local($., $@, $!, $^E, $?); | |
my $self = shift; | |
# Make sure we always remove the file from the global hash | |
# on destruction. This prevents the hash from growing uncontrollably | |
# and post-destruction there is no reason to know about the file. | |
my $file = $self->filename; | |
my $was_created_by_proc; | |
if (exists $FILES_CREATED_BY_OBJECT{$$}{$file}) { | |
$was_created_by_proc = 1; | |
delete $FILES_CREATED_BY_OBJECT{$$}{$file}; | |
} | |
if (${*$self}{UNLINK} && !$KEEP_ALL) { | |
print "# ---------> Unlinking $self\n" if $DEBUG; | |
# only delete if this process created it | |
return unless $was_created_by_proc; | |
# The unlink1 may fail if the file has been closed | |
# by the caller. This leaves us with the decision | |
# of whether to refuse to remove the file or simply | |
# do an unlink without test. Seems to be silly | |
# to do this when we are trying to be careful | |
# about security | |
_force_writable( $file ); # for windows | |
unlink1( $self, $file ) | |
or unlink($file); | |
} | |
} | |
#pod =back | |
#pod | |
#pod =head1 FUNCTIONS | |
#pod | |
#pod This section describes the recommended interface for generating | |
#pod temporary files and directories. | |
#pod | |
#pod =over 4 | |
#pod | |
#pod =item B<tempfile> | |
#pod | |
#pod This is the basic function to generate temporary files. | |
#pod The behaviour of the file can be changed using various options: | |
#pod | |
#pod $fh = tempfile(); | |
#pod ($fh, $filename) = tempfile(); | |
#pod | |
#pod Create a temporary file in the directory specified for temporary | |
#pod files, as specified by the tmpdir() function in L<File::Spec>. | |
#pod | |
#pod ($fh, $filename) = tempfile($template); | |
#pod | |
#pod Create a temporary file in the current directory using the supplied | |
#pod template. Trailing `X' characters are replaced with random letters to | |
#pod generate the filename. At least four `X' characters must be present | |
#pod at the end of the template. | |
#pod | |
#pod ($fh, $filename) = tempfile($template, SUFFIX => $suffix) | |
#pod | |
#pod Same as previously, except that a suffix is added to the template | |
#pod after the `X' translation. Useful for ensuring that a temporary | |
#pod filename has a particular extension when needed by other applications. | |
#pod But see the WARNING at the end. | |
#pod | |
#pod ($fh, $filename) = tempfile($template, DIR => $dir); | |
#pod | |
#pod Translates the template as before except that a directory name | |
#pod is specified. | |
#pod | |
#pod ($fh, $filename) = tempfile($template, TMPDIR => 1); | |
#pod | |
#pod Equivalent to specifying a DIR of "File::Spec->tmpdir", writing the file | |
#pod into the same temporary directory as would be used if no template was | |
#pod specified at all. | |
#pod | |
#pod ($fh, $filename) = tempfile($template, UNLINK => 1); | |
#pod | |
#pod Return the filename and filehandle as before except that the file is | |
#pod automatically removed when the program exits (dependent on | |
#pod $KEEP_ALL). Default is for the file to be removed if a file handle is | |
#pod requested and to be kept if the filename is requested. In a scalar | |
#pod context (where no filename is returned) the file is always deleted | |
#pod either (depending on the operating system) on exit or when it is | |
#pod closed (unless $KEEP_ALL is true when the temp file is created). | |
#pod | |
#pod Use the object-oriented interface if fine-grained control of when | |
#pod a file is removed is required. | |
#pod | |
#pod If the template is not specified, a template is always | |
#pod automatically generated. This temporary file is placed in tmpdir() | |
#pod (L<File::Spec>) unless a directory is specified explicitly with the | |
#pod DIR option. | |
#pod | |
#pod $fh = tempfile( DIR => $dir ); | |
#pod | |
#pod If called in scalar context, only the filehandle is returned and the | |
#pod file will automatically be deleted when closed on operating systems | |
#pod that support this (see the description of tmpfile() elsewhere in this | |
#pod document). This is the preferred mode of operation, as if you only | |
#pod have a filehandle, you can never create a race condition by fumbling | |
#pod with the filename. On systems that can not unlink an open file or can | |
#pod not mark a file as temporary when it is opened (for example, Windows | |
#pod NT uses the C<O_TEMPORARY> flag) the file is marked for deletion when | |
#pod the program ends (equivalent to setting UNLINK to 1). The C<UNLINK> | |
#pod flag is ignored if present. | |
#pod | |
#pod (undef, $filename) = tempfile($template, OPEN => 0); | |
#pod | |
#pod This will return the filename based on the template but | |
#pod will not open this file. Cannot be used in conjunction with | |
#pod UNLINK set to true. Default is to always open the file | |
#pod to protect from possible race conditions. A warning is issued | |
#pod if warnings are turned on. Consider using the tmpnam() | |
#pod and mktemp() functions described elsewhere in this document | |
#pod if opening the file is not required. | |
#pod | |
#pod To open the temporary filehandle with O_EXLOCK (open with exclusive | |
#pod file lock) use C<< EXLOCK=>1 >>. This is supported only by some | |
#pod operating systems (most notably BSD derived systems). By default | |
#pod EXLOCK will be false. Former C<File::Temp> versions set EXLOCK to | |
#pod true, so to be sure to get an unlocked filehandle also with older | |
#pod versions, explicitly set C<< EXLOCK=>0 >>. | |
#pod | |
#pod ($fh, $filename) = tempfile($template, EXLOCK => 1); | |
#pod | |
#pod By default, the temp file is created with 0600 file permissions. | |
#pod Use C<PERMS> to change this: | |
#pod | |
#pod ($fh, $filename) = tempfile($template, PERMS => 0666); | |
#pod | |
#pod Options can be combined as required. | |
#pod | |
#pod Will croak() if there is an error. | |
#pod | |
#pod Available since 0.05. | |
#pod | |
#pod UNLINK flag available since 0.10. | |
#pod | |
#pod TMPDIR flag available since 0.19. | |
#pod | |
#pod EXLOCK flag available since 0.19. | |
#pod | |
#pod PERMS flag available since 0.2310. | |
#pod | |
#pod =cut | |
sub tempfile { | |
if ( @_ && $_[0] eq 'File::Temp' ) { | |
croak "'tempfile' can't be called as a method"; | |
} | |
# Can not check for argument count since we can have any | |
# number of args | |
# Default options | |
my %options = ( | |
"DIR" => undef, # Directory prefix | |
"SUFFIX" => '', # Template suffix | |
"UNLINK" => 0, # Do not unlink file on exit | |
"OPEN" => 1, # Open file | |
"TMPDIR" => 0, # Place tempfile in tempdir if template specified | |
"EXLOCK" => 0, # Open file with O_EXLOCK | |
"PERMS" => undef, # File permissions | |
); | |
# Check to see whether we have an odd or even number of arguments | |
my ($maybe_template, $args) = _parse_args(@_); | |
my $template = @$maybe_template ? $maybe_template->[0] : undef; | |
# Read the options and merge with defaults | |
%options = (%options, %$args); | |
# First decision is whether or not to open the file | |
if (! $options{"OPEN"}) { | |
warn "tempfile(): temporary filename requested but not opened.\nPossibly unsafe, consider using tempfile() with OPEN set to true\n" | |
if $^W; | |
} | |
if ($options{"DIR"} and $^O eq 'VMS') { | |
# on VMS turn []foo into [.foo] for concatenation | |
$options{"DIR"} = VMS::Filespec::vmspath($options{"DIR"}); | |
} | |
# Construct the template | |
# Have a choice of trying to work around the mkstemp/mktemp/tmpnam etc | |
# functions or simply constructing a template and using _gettemp() | |
# explicitly. Go for the latter | |
# First generate a template if not defined and prefix the directory | |
# If no template must prefix the temp directory | |
if (defined $template) { | |
# End up with current directory if neither DIR not TMPDIR are set | |
if ($options{"DIR"}) { | |
$template = File::Spec->catfile($options{"DIR"}, $template); | |
} elsif ($options{TMPDIR}) { | |
$template = File::Spec->catfile(_wrap_file_spec_tmpdir(), $template ); | |
} | |
} else { | |
if ($options{"DIR"}) { | |
$template = File::Spec->catfile($options{"DIR"}, TEMPXXX); | |
} else { | |
$template = File::Spec->catfile(_wrap_file_spec_tmpdir(), TEMPXXX); | |
} | |
} | |
# Now add a suffix | |
$template .= $options{"SUFFIX"}; | |
# Determine whether we should tell _gettemp to unlink the file | |
# On unix this is irrelevant and can be worked out after the file is | |
# opened (simply by unlinking the open filehandle). On Windows or VMS | |
# we have to indicate temporary-ness when we open the file. In general | |
# we only want a true temporary file if we are returning just the | |
# filehandle - if the user wants the filename they probably do not | |
# want the file to disappear as soon as they close it (which may be | |
# important if they want a child process to use the file) | |
# For this reason, tie unlink_on_close to the return context regardless | |
# of OS. | |
my $unlink_on_close = ( wantarray ? 0 : 1); | |
# Create the file | |
my ($fh, $path, $errstr); | |
croak "Error in tempfile() using template $template: $errstr" | |
unless (($fh, $path) = _gettemp($template, | |
"open" => $options{OPEN}, | |
"mkdir" => 0, | |
"unlink_on_close" => $unlink_on_close, | |
"suffixlen" => length($options{SUFFIX}), | |
"ErrStr" => \$errstr, | |
"use_exlock" => $options{EXLOCK}, | |
"file_permissions" => $options{PERMS}, | |
) ); | |
# Set up an exit handler that can do whatever is right for the | |
# system. This removes files at exit when requested explicitly or when | |
# system is asked to unlink_on_close but is unable to do so because | |
# of OS limitations. | |
# The latter should be achieved by using a tied filehandle. | |
# Do not check return status since this is all done with END blocks. | |
_deferred_unlink($fh, $path, 0) if $options{"UNLINK"}; | |
# Return | |
if (wantarray()) { | |
if ($options{'OPEN'}) { | |
return ($fh, $path); | |
} else { | |
return (undef, $path); | |
} | |
} else { | |
# Unlink the file. It is up to unlink0 to decide what to do with | |
# this (whether to unlink now or to defer until later) | |
unlink0($fh, $path) or croak "Error unlinking file $path using unlink0"; | |
# Return just the filehandle. | |
return $fh; | |
} | |
} | |
# On Windows under taint mode, File::Spec could suggest "C:\" as a tempdir | |
# which might not be writable. If that is the case, we fallback to a | |
# user directory. See https://rt.cpan.org/Ticket/Display.html?id=60340 | |
{ | |
my ($alt_tmpdir, $checked); | |
sub _wrap_file_spec_tmpdir { | |
return File::Spec->tmpdir unless $^O eq "MSWin32" && ${^TAINT}; | |
if ( $checked ) { | |
return $alt_tmpdir ? $alt_tmpdir : File::Spec->tmpdir; | |
} | |
# probe what File::Spec gives and find a fallback | |
my $xxpath = _replace_XX( "X" x 10, 0 ); | |
# First, see if File::Spec->tmpdir is writable | |
my $tmpdir = File::Spec->tmpdir; | |
my $testpath = File::Spec->catdir( $tmpdir, $xxpath ); | |
if (mkdir( $testpath, 0700) ) { | |
$checked = 1; | |
rmdir $testpath; | |
return $tmpdir; | |
} | |
# Next, see if CSIDL_LOCAL_APPDATA is writable | |
require Win32; | |
my $local_app = File::Spec->catdir( | |
Win32::GetFolderPath( Win32::CSIDL_LOCAL_APPDATA() ), 'Temp' | |
); | |
$testpath = File::Spec->catdir( $local_app, $xxpath ); | |
if ( -e $local_app or mkdir( $local_app, 0700 ) ) { | |
if (mkdir( $testpath, 0700) ) { | |
$checked = 1; | |
rmdir $testpath; | |
return $alt_tmpdir = $local_app; | |
} | |
} | |
# Can't find something writable | |
croak << "HERE"; | |
Couldn't find a writable temp directory in taint mode. Tried: | |
$tmpdir | |
$local_app | |
Try setting and untainting the TMPDIR environment variable. | |
HERE | |
} | |
} | |
#pod =item B<tempdir> | |
#pod | |
#pod This is the recommended interface for creation of temporary | |
#pod directories. By default the directory will not be removed on exit | |
#pod (that is, it won't be temporary; this behaviour can not be changed | |
#pod because of issues with backwards compatibility). To enable removal | |
#pod either use the CLEANUP option which will trigger removal on program | |
#pod exit, or consider using the "newdir" method in the object interface which | |
#pod will allow the directory to be cleaned up when the object goes out of | |
#pod scope. | |
#pod | |
#pod The behaviour of the function depends on the arguments: | |
#pod | |
#pod $tempdir = tempdir(); | |
#pod | |
#pod Create a directory in tmpdir() (see L<File::Spec|File::Spec>). | |
#pod | |
#pod $tempdir = tempdir( $template ); | |
#pod | |
#pod Create a directory from the supplied template. This template is | |
#pod similar to that described for tempfile(). `X' characters at the end | |
#pod of the template are replaced with random letters to construct the | |
#pod directory name. At least four `X' characters must be in the template. | |
#pod | |
#pod $tempdir = tempdir ( DIR => $dir ); | |
#pod | |
#pod Specifies the directory to use for the temporary directory. | |
#pod The temporary directory name is derived from an internal template. | |
#pod | |
#pod $tempdir = tempdir ( $template, DIR => $dir ); | |
#pod | |
#pod Prepend the supplied directory name to the template. The template | |
#pod should not include parent directory specifications itself. Any parent | |
#pod directory specifications are removed from the template before | |
#pod prepending the supplied directory. | |
#pod | |
#pod $tempdir = tempdir ( $template, TMPDIR => 1 ); | |
#pod | |
#pod Using the supplied template, create the temporary directory in | |
#pod a standard location for temporary files. Equivalent to doing | |
#pod | |
#pod $tempdir = tempdir ( $template, DIR => File::Spec->tmpdir); | |
#pod | |
#pod but shorter. Parent directory specifications are stripped from the | |
#pod template itself. The C<TMPDIR> option is ignored if C<DIR> is set | |
#pod explicitly. Additionally, C<TMPDIR> is implied if neither a template | |
#pod nor a directory are supplied. | |
#pod | |
#pod $tempdir = tempdir( $template, CLEANUP => 1); | |
#pod | |
#pod Create a temporary directory using the supplied template, but | |
#pod attempt to remove it (and all files inside it) when the program | |
#pod exits. Note that an attempt will be made to remove all files from | |
#pod the directory even if they were not created by this module (otherwise | |
#pod why ask to clean it up?). The directory removal is made with | |
#pod the rmtree() function from the L<File::Path|File::Path> module. | |
#pod Of course, if the template is not specified, the temporary directory | |
#pod will be created in tmpdir() and will also be removed at program exit. | |
#pod | |
#pod Will croak() if there is an error. | |
#pod | |
#pod Current API available since 0.05. | |
#pod | |
#pod =cut | |
# ' | |
sub tempdir { | |
if ( @_ && $_[0] eq 'File::Temp' ) { | |
croak "'tempdir' can't be called as a method"; | |
} | |
# Can not check for argument count since we can have any | |
# number of args | |
# Default options | |
my %options = ( | |
"CLEANUP" => 0, # Remove directory on exit | |
"DIR" => '', # Root directory | |
"TMPDIR" => 0, # Use tempdir with template | |
); | |
# Check to see whether we have an odd or even number of arguments | |
my ($maybe_template, $args) = _parse_args(@_); | |
my $template = @$maybe_template ? $maybe_template->[0] : undef; | |
# Read the options and merge with defaults | |
%options = (%options, %$args); | |
# Modify or generate the template | |
# Deal with the DIR and TMPDIR options | |
if (defined $template) { | |
# Need to strip directory path if using DIR or TMPDIR | |
if ($options{'TMPDIR'} || $options{'DIR'}) { | |
# Strip parent directory from the filename | |
# | |
# There is no filename at the end | |
$template = VMS::Filespec::vmspath($template) if $^O eq 'VMS'; | |
my ($volume, $directories, undef) = File::Spec->splitpath( $template, 1); | |
# Last directory is then our template | |
$template = (File::Spec->splitdir($directories))[-1]; | |
# Prepend the supplied directory or temp dir | |
if ($options{"DIR"}) { | |
$template = File::Spec->catdir($options{"DIR"}, $template); | |
} elsif ($options{TMPDIR}) { | |
# Prepend tmpdir | |
$template = File::Spec->catdir(_wrap_file_spec_tmpdir(), $template); | |
} | |
} | |
} else { | |
if ($options{"DIR"}) { | |
$template = File::Spec->catdir($options{"DIR"}, TEMPXXX); | |
} else { | |
$template = File::Spec->catdir(_wrap_file_spec_tmpdir(), TEMPXXX); | |
} | |
} | |
# Create the directory | |
my $tempdir; | |
my $suffixlen = 0; | |
if ($^O eq 'VMS') { # dir names can end in delimiters | |
$template =~ m/([\.\]:>]+)$/; | |
$suffixlen = length($1); | |
} | |
if ( ($^O eq 'MacOS') && (substr($template, -1) eq ':') ) { | |
# dir name has a trailing ':' | |
++$suffixlen; | |
} | |
my $errstr; | |
croak "Error in tempdir() using $template: $errstr" | |
unless ((undef, $tempdir) = _gettemp($template, | |
"open" => 0, | |
"mkdir"=> 1 , | |
"suffixlen" => $suffixlen, | |
"ErrStr" => \$errstr, | |
) ); | |
# Install exit handler; must be dynamic to get lexical | |
if ( $options{'CLEANUP'} && -d $tempdir) { | |
_deferred_unlink(undef, $tempdir, 1); | |
} | |
# Return the dir name | |
return $tempdir; | |
} | |
#pod =back | |
#pod | |
#pod =head1 MKTEMP FUNCTIONS | |
#pod | |
#pod The following functions are Perl implementations of the | |
#pod mktemp() family of temp file generation system calls. | |
#pod | |
#pod =over 4 | |
#pod | |
#pod =item B<mkstemp> | |
#pod | |
#pod Given a template, returns a filehandle to the temporary file and the name | |
#pod of the file. | |
#pod | |
#pod ($fh, $name) = mkstemp( $template ); | |
#pod | |
#pod In scalar context, just the filehandle is returned. | |
#pod | |
#pod The template may be any filename with some number of X's appended | |
#pod to it, for example F</tmp/temp.XXXX>. The trailing X's are replaced | |
#pod with unique alphanumeric combinations. | |
#pod | |
#pod Will croak() if there is an error. | |
#pod | |
#pod Current API available since 0.05. | |
#pod | |
#pod =cut | |
sub mkstemp { | |
croak "Usage: mkstemp(template)" | |
if scalar(@_) != 1; | |
my $template = shift; | |
my ($fh, $path, $errstr); | |
croak "Error in mkstemp using $template: $errstr" | |
unless (($fh, $path) = _gettemp($template, | |
"open" => 1, | |
"mkdir"=> 0 , | |
"suffixlen" => 0, | |
"ErrStr" => \$errstr, | |
) ); | |
if (wantarray()) { | |
return ($fh, $path); | |
} else { | |
return $fh; | |
} | |
} | |
#pod =item B<mkstemps> | |
#pod | |
#pod Similar to mkstemp(), except that an extra argument can be supplied | |
#pod with a suffix to be appended to the template. | |
#pod | |
#pod ($fh, $name) = mkstemps( $template, $suffix ); | |
#pod | |
#pod For example a template of C<testXXXXXX> and suffix of C<.dat> | |
#pod would generate a file similar to F<testhGji_w.dat>. | |
#pod | |
#pod Returns just the filehandle alone when called in scalar context. | |
#pod | |
#pod Will croak() if there is an error. | |
#pod | |
#pod Current API available since 0.05. | |
#pod | |
#pod =cut | |
sub mkstemps { | |
croak "Usage: mkstemps(template, suffix)" | |
if scalar(@_) != 2; | |
my $template = shift; | |
my $suffix = shift; | |
$template .= $suffix; | |
my ($fh, $path, $errstr); | |
croak "Error in mkstemps using $template: $errstr" | |
unless (($fh, $path) = _gettemp($template, | |
"open" => 1, | |
"mkdir"=> 0 , | |
"suffixlen" => length($suffix), | |
"ErrStr" => \$errstr, | |
) ); | |
if (wantarray()) { | |
return ($fh, $path); | |
} else { | |
return $fh; | |
} | |
} | |
#pod =item B<mkdtemp> | |
#pod | |
#pod Create a directory from a template. The template must end in | |
#pod X's that are replaced by the routine. | |
#pod | |
#pod $tmpdir_name = mkdtemp($template); | |
#pod | |
#pod Returns the name of the temporary directory created. | |
#pod | |
#pod Directory must be removed by the caller. | |
#pod | |
#pod Will croak() if there is an error. | |
#pod | |
#pod Current API available since 0.05. | |
#pod | |
#pod =cut | |
#' # for emacs | |
sub mkdtemp { | |
croak "Usage: mkdtemp(template)" | |
if scalar(@_) != 1; | |
my $template = shift; | |
my $suffixlen = 0; | |
if ($^O eq 'VMS') { # dir names can end in delimiters | |
$template =~ m/([\.\]:>]+)$/; | |
$suffixlen = length($1); | |
} | |
if ( ($^O eq 'MacOS') && (substr($template, -1) eq ':') ) { | |
# dir name has a trailing ':' | |
++$suffixlen; | |
} | |
my ($junk, $tmpdir, $errstr); | |
croak "Error creating temp directory from template $template\: $errstr" | |
unless (($junk, $tmpdir) = _gettemp($template, | |
"open" => 0, | |
"mkdir"=> 1 , | |
"suffixlen" => $suffixlen, | |
"ErrStr" => \$errstr, | |
) ); | |
return $tmpdir; | |
} | |
#pod =item B<mktemp> | |
#pod | |
#pod Returns a valid temporary filename but does not guarantee | |
#pod that the file will not be opened by someone else. | |
#pod | |
#pod $unopened_file = mktemp($template); | |
#pod | |
#pod Template is the same as that required by mkstemp(). | |
#pod | |
#pod Will croak() if there is an error. | |
#pod | |
#pod Current API available since 0.05. | |
#pod | |
#pod =cut | |
sub mktemp { | |
croak "Usage: mktemp(template)" | |
if scalar(@_) != 1; | |
my $template = shift; | |
my ($tmpname, $junk, $errstr); | |
croak "Error getting name to temp file from template $template: $errstr" | |
unless (($junk, $tmpname) = _gettemp($template, | |
"open" => 0, | |
"mkdir"=> 0 , | |
"suffixlen" => 0, | |
"ErrStr" => \$errstr, | |
) ); | |
return $tmpname; | |
} | |
#pod =back | |
#pod | |
#pod =head1 POSIX FUNCTIONS | |
#pod | |
#pod This section describes the re-implementation of the tmpnam() | |
#pod and tmpfile() functions described in L<POSIX> | |
#pod using the mkstemp() from this module. | |
#pod | |
#pod Unlike the L<POSIX|POSIX> implementations, the directory used | |
#pod for the temporary file is not specified in a system include | |
#pod file (C<P_tmpdir>) but simply depends on the choice of tmpdir() | |
#pod returned by L<File::Spec|File::Spec>. On some implementations this | |
#pod location can be set using the C<TMPDIR> environment variable, which | |
#pod may not be secure. | |
#pod If this is a problem, simply use mkstemp() and specify a template. | |
#pod | |
#pod =over 4 | |
#pod | |
#pod =item B<tmpnam> | |
#pod | |
#pod When called in scalar context, returns the full name (including path) | |
#pod of a temporary file (uses mktemp()). The only check is that the file does | |
#pod not already exist, but there is no guarantee that that condition will | |
#pod continue to apply. | |
#pod | |
#pod $file = tmpnam(); | |
#pod | |
#pod When called in list context, a filehandle to the open file and | |
#pod a filename are returned. This is achieved by calling mkstemp() | |
#pod after constructing a suitable template. | |
#pod | |
#pod ($fh, $file) = tmpnam(); | |
#pod | |
#pod If possible, this form should be used to prevent possible | |
#pod race conditions. | |
#pod | |
#pod See L<File::Spec/tmpdir> for information on the choice of temporary | |
#pod directory for a particular operating system. | |
#pod | |
#pod Will croak() if there is an error. | |
#pod | |
#pod Current API available since 0.05. | |
#pod | |
#pod =cut | |
sub tmpnam { | |
# Retrieve the temporary directory name | |
my $tmpdir = _wrap_file_spec_tmpdir(); | |
# XXX I don't know under what circumstances this occurs, -- xdg 2016-04-02 | |
croak "Error temporary directory is not writable" | |
if $tmpdir eq ''; | |
# Use a ten character template and append to tmpdir | |
my $template = File::Spec->catfile($tmpdir, TEMPXXX); | |
if (wantarray() ) { | |
return mkstemp($template); | |
} else { | |
return mktemp($template); | |
} | |
} | |
#pod =item B<tmpfile> | |
#pod | |
#pod Returns the filehandle of a temporary file. | |
#pod | |
#pod $fh = tmpfile(); | |
#pod | |
#pod The file is removed when the filehandle is closed or when the program | |
#pod exits. No access to the filename is provided. | |
#pod | |
#pod If the temporary file can not be created undef is returned. | |
#pod Currently this command will probably not work when the temporary | |
#pod directory is on an NFS file system. | |
#pod | |
#pod Will croak() if there is an error. | |
#pod | |
#pod Available since 0.05. | |
#pod | |
#pod Returning undef if unable to create file added in 0.12. | |
#pod | |
#pod =cut | |
sub tmpfile { | |
# Simply call tmpnam() in a list context | |
my ($fh, $file) = tmpnam(); | |
# Make sure file is removed when filehandle is closed | |
# This will fail on NFS | |
unlink0($fh, $file) | |
or return undef; | |
return $fh; | |
} | |
#pod =back | |
#pod | |
#pod =head1 ADDITIONAL FUNCTIONS | |
#pod | |
#pod These functions are provided for backwards compatibility | |
#pod with common tempfile generation C library functions. | |
#pod | |
#pod They are not exported and must be addressed using the full package | |
#pod name. | |
#pod | |
#pod =over 4 | |
#pod | |
#pod =item B<tempnam> | |
#pod | |
#pod Return the name of a temporary file in the specified directory | |
#pod using a prefix. The file is guaranteed not to exist at the time | |
#pod the function was called, but such guarantees are good for one | |
#pod clock tick only. Always use the proper form of C<sysopen> | |
#pod with C<O_CREAT | O_EXCL> if you must open such a filename. | |
#pod | |
#pod $filename = File::Temp::tempnam( $dir, $prefix ); | |
#pod | |
#pod Equivalent to running mktemp() with $dir/$prefixXXXXXXXX | |
#pod (using unix file convention as an example) | |
#pod | |
#pod Because this function uses mktemp(), it can suffer from race conditions. | |
#pod | |
#pod Will croak() if there is an error. | |
#pod | |
#pod Current API available since 0.05. | |
#pod | |
#pod =cut | |
sub tempnam { | |
croak 'Usage tempnam($dir, $prefix)' unless scalar(@_) == 2; | |
my ($dir, $prefix) = @_; | |
# Add a string to the prefix | |
$prefix .= 'XXXXXXXX'; | |
# Concatenate the directory to the file | |
my $template = File::Spec->catfile($dir, $prefix); | |
return mktemp($template); | |
} | |
#pod =back | |
#pod | |
#pod =head1 UTILITY FUNCTIONS | |
#pod | |
#pod Useful functions for dealing with the filehandle and filename. | |
#pod | |
#pod =over 4 | |
#pod | |
#pod =item B<unlink0> | |
#pod | |
#pod Given an open filehandle and the associated filename, make a safe | |
#pod unlink. This is achieved by first checking that the filename and | |
#pod filehandle initially point to the same file and that the number of | |
#pod links to the file is 1 (all fields returned by stat() are compared). | |
#pod Then the filename is unlinked and the filehandle checked once again to | |
#pod verify that the number of links on that file is now 0. This is the | |
#pod closest you can come to making sure that the filename unlinked was the | |
#pod same as the file whose descriptor you hold. | |
#pod | |
#pod unlink0($fh, $path) | |
#pod or die "Error unlinking file $path safely"; | |
#pod | |
#pod Returns false on error but croaks() if there is a security | |
#pod anomaly. The filehandle is not closed since on some occasions this is | |
#pod not required. | |
#pod | |
#pod On some platforms, for example Windows NT, it is not possible to | |
#pod unlink an open file (the file must be closed first). On those | |
#pod platforms, the actual unlinking is deferred until the program ends and | |
#pod good status is returned. A check is still performed to make sure that | |
#pod the filehandle and filename are pointing to the same thing (but not at | |
#pod the time the end block is executed since the deferred removal may not | |
#pod have access to the filehandle). | |
#pod | |
#pod Additionally, on Windows NT not all the fields returned by stat() can | |
#pod be compared. For example, the C<dev> and C<rdev> fields seem to be | |
#pod different. Also, it seems that the size of the file returned by stat() | |
#pod does not always agree, with C<stat(FH)> being more accurate than | |
#pod C<stat(filename)>, presumably because of caching issues even when | |
#pod using autoflush (this is usually overcome by waiting a while after | |
#pod writing to the tempfile before attempting to C<unlink0> it). | |
#pod | |
#pod Finally, on NFS file systems the link count of the file handle does | |
#pod not always go to zero immediately after unlinking. Currently, this | |
#pod command is expected to fail on NFS disks. | |
#pod | |
#pod This function is disabled if the global variable $KEEP_ALL is true | |
#pod and an unlink on open file is supported. If the unlink is to be deferred | |
#pod to the END block, the file is still registered for removal. | |
#pod | |
#pod This function should not be called if you are using the object oriented | |
#pod interface since the it will interfere with the object destructor deleting | |
#pod the file. | |
#pod | |
#pod Available Since 0.05. | |
#pod | |
#pod If can not unlink open file, defer removal until later available since 0.06. | |
#pod | |
#pod =cut | |
sub unlink0 { | |
croak 'Usage: unlink0(filehandle, filename)' | |
unless scalar(@_) == 2; | |
# Read args | |
my ($fh, $path) = @_; | |
cmpstat($fh, $path) or return 0; | |
# attempt remove the file (does not work on some platforms) | |
if (_can_unlink_opened_file()) { | |
# return early (Without unlink) if we have been instructed to retain files. | |
return 1 if $KEEP_ALL; | |
# XXX: do *not* call this on a directory; possible race | |
# resulting in recursive removal | |
croak "unlink0: $path has become a directory!" if -d $path; | |
unlink($path) or return 0; | |
# Stat the filehandle | |
my @fh = stat $fh; | |
print "Link count = $fh[3] \n" if $DEBUG; | |
# Make sure that the link count is zero | |
# - Cygwin provides deferred unlinking, however, | |
# on Win9x the link count remains 1 | |
# On NFS the link count may still be 1 but we can't know that | |
# we are on NFS. Since we can't be sure, we'll defer it | |
return 1 if $fh[3] == 0 || $^O eq 'cygwin'; | |
} | |
# fall-through if we can't unlink now | |
_deferred_unlink($fh, $path, 0); | |
return 1; | |
} | |
#pod =item B<cmpstat> | |
#pod | |
#pod Compare C<stat> of filehandle with C<stat> of provided filename. This | |
#pod can be used to check that the filename and filehandle initially point | |
#pod to the same file and that the number of links to the file is 1 (all | |
#pod fields returned by stat() are compared). | |
#pod | |
#pod cmpstat($fh, $path) | |
#pod or die "Error comparing handle with file"; | |
#pod | |
#pod Returns false if the stat information differs or if the link count is | |
#pod greater than 1. Calls croak if there is a security anomaly. | |
#pod | |
#pod On certain platforms, for example Windows, not all the fields returned by stat() | |
#pod can be compared. For example, the C<dev> and C<rdev> fields seem to be | |
#pod different in Windows. Also, it seems that the size of the file | |
#pod returned by stat() does not always agree, with C<stat(FH)> being more | |
#pod accurate than C<stat(filename)>, presumably because of caching issues | |
#pod even when using autoflush (this is usually overcome by waiting a while | |
#pod after writing to the tempfile before attempting to C<unlink0> it). | |
#pod | |
#pod Not exported by default. | |
#pod | |
#pod Current API available since 0.14. | |
#pod | |
#pod =cut | |
sub cmpstat { | |
croak 'Usage: cmpstat(filehandle, filename)' | |
unless scalar(@_) == 2; | |
# Read args | |
my ($fh, $path) = @_; | |
warn "Comparing stat\n" | |
if $DEBUG; | |
# Stat the filehandle - which may be closed if someone has manually | |
# closed the file. Can not turn off warnings without using $^W | |
# unless we upgrade to 5.006 minimum requirement | |
my @fh; | |
{ | |
local ($^W) = 0; | |
@fh = stat $fh; | |
} | |
return unless @fh; | |
if ($fh[3] > 1 && $^W) { | |
carp "unlink0: fstat found too many links; SB=@fh" if $^W; | |
} | |
# Stat the path | |
my @path = stat $path; | |
unless (@path) { | |
carp "unlink0: $path is gone already" if $^W; | |
return; | |
} | |
# this is no longer a file, but may be a directory, or worse | |
unless (-f $path) { | |
confess "panic: $path is no longer a file: SB=@fh"; | |
} | |
# Do comparison of each member of the array | |
# On WinNT dev and rdev seem to be different | |
# depending on whether it is a file or a handle. | |
# Cannot simply compare all members of the stat return | |
# Select the ones we can use | |
my @okstat = (0..$#fh); # Use all by default | |
if ($^O eq 'MSWin32') { | |
@okstat = (1,2,3,4,5,7,8,9,10); | |
} elsif ($^O eq 'os2') { | |
@okstat = (0, 2..$#fh); | |
} elsif ($^O eq 'VMS') { # device and file ID are sufficient | |
@okstat = (0, 1); | |
} elsif ($^O eq 'dos') { | |
@okstat = (0,2..7,11..$#fh); | |
} elsif ($^O eq 'mpeix') { | |
@okstat = (0..4,8..10); | |
} | |
# Now compare each entry explicitly by number | |
for (@okstat) { | |
print "Comparing: $_ : $fh[$_] and $path[$_]\n" if $DEBUG; | |
# Use eq rather than == since rdev, blksize, and blocks (6, 11, | |
# and 12) will be '' on platforms that do not support them. This | |
# is fine since we are only comparing integers. | |
unless ($fh[$_] eq $path[$_]) { | |
warn "Did not match $_ element of stat\n" if $DEBUG; | |
return 0; | |
} | |
} | |
return 1; | |
} | |
#pod =item B<unlink1> | |
#pod | |
#pod Similar to C<unlink0> except after file comparison using cmpstat, the | |
#pod filehandle is closed prior to attempting to unlink the file. This | |
#pod allows the file to be removed without using an END block, but does | |
#pod mean that the post-unlink comparison of the filehandle state provided | |
#pod by C<unlink0> is not available. | |
#pod | |
#pod unlink1($fh, $path) | |
#pod or die "Error closing and unlinking file"; | |
#pod | |
#pod Usually called from the object destructor when using the OO interface. | |
#pod | |
#pod Not exported by default. | |
#pod | |
#pod This function is disabled if the global variable $KEEP_ALL is true. | |
#pod | |
#pod Can call croak() if there is a security anomaly during the stat() | |
#pod comparison. | |
#pod | |
#pod Current API available since 0.14. | |
#pod | |
#pod =cut | |
sub unlink1 { | |
croak 'Usage: unlink1(filehandle, filename)' | |
unless scalar(@_) == 2; | |
# Read args | |
my ($fh, $path) = @_; | |
cmpstat($fh, $path) or return 0; | |
# Close the file | |
close( $fh ) or return 0; | |
# Make sure the file is writable (for windows) | |
_force_writable( $path ); | |
# return early (without unlink) if we have been instructed to retain files. | |
return 1 if $KEEP_ALL; | |
# remove the file | |
return unlink($path); | |
} | |
#pod =item B<cleanup> | |
#pod | |
#pod Calling this function will cause any temp files or temp directories | |
#pod that are registered for removal to be removed. This happens automatically | |
#pod when the process exits but can be triggered manually if the caller is sure | |
#pod that none of the temp files are required. This method can be registered as | |
#pod an Apache callback. | |
#pod | |
#pod Note that if a temp directory is your current directory, it cannot be | |
#pod removed. C<chdir()> out of the directory first before calling | |
#pod C<cleanup()>. (For the cleanup at program exit when the CLEANUP flag | |
#pod is set, this happens automatically.) | |
#pod | |
#pod On OSes where temp files are automatically removed when the temp file | |
#pod is closed, calling this function will have no effect other than to remove | |
#pod temporary directories (which may include temporary files). | |
#pod | |
#pod File::Temp::cleanup(); | |
#pod | |
#pod Not exported by default. | |
#pod | |
#pod Current API available since 0.15. | |
#pod | |
#pod =back | |
#pod | |
#pod =head1 PACKAGE VARIABLES | |
#pod | |
#pod These functions control the global state of the package. | |
#pod | |
#pod =over 4 | |
#pod | |
#pod =item B<safe_level> | |
#pod | |
#pod Controls the lengths to which the module will go to check the safety of the | |
#pod temporary file or directory before proceeding. | |
#pod Options are: | |
#pod | |
#pod =over 8 | |
#pod | |
#pod =item STANDARD | |
#pod | |
#pod Do the basic security measures to ensure the directory exists and is | |
#pod writable, that temporary files are opened only if they do not already | |
#pod exist, and that possible race conditions are avoided. Finally the | |
#pod L<unlink0|"unlink0"> function is used to remove files safely. | |
#pod | |
#pod =item MEDIUM | |
#pod | |
#pod In addition to the STANDARD security, the output directory is checked | |
#pod to make sure that it is owned either by root or the user running the | |
#pod program. If the directory is writable by group or by other, it is then | |
#pod checked to make sure that the sticky bit is set. | |
#pod | |
#pod Will not work on platforms that do not support the C<-k> test | |
#pod for sticky bit. | |
#pod | |
#pod =item HIGH | |
#pod | |
#pod In addition to the MEDIUM security checks, also check for the | |
#pod possibility of ``chown() giveaway'' using the L<POSIX|POSIX> | |
#pod sysconf() function. If this is a possibility, each directory in the | |
#pod path is checked in turn for safeness, recursively walking back to the | |
#pod root directory. | |
#pod | |
#pod For platforms that do not support the L<POSIX|POSIX> | |
#pod C<_PC_CHOWN_RESTRICTED> symbol (for example, Windows NT) it is | |
#pod assumed that ``chown() giveaway'' is possible and the recursive test | |
#pod is performed. | |
#pod | |
#pod =back | |
#pod | |
#pod The level can be changed as follows: | |
#pod | |
#pod File::Temp->safe_level( File::Temp::HIGH ); | |
#pod | |
#pod The level constants are not exported by the module. | |
#pod | |
#pod Currently, you must be running at least perl v5.6.0 in order to | |
#pod run with MEDIUM or HIGH security. This is simply because the | |
#pod safety tests use functions from L<Fcntl|Fcntl> that are not | |
#pod available in older versions of perl. The problem is that the version | |
#pod number for Fcntl is the same in perl 5.6.0 and in 5.005_03 even though | |
#pod they are different versions. | |
#pod | |
#pod On systems that do not support the HIGH or MEDIUM safety levels | |
#pod (for example Win NT or OS/2) any attempt to change the level will | |
#pod be ignored. The decision to ignore rather than raise an exception | |
#pod allows portable programs to be written with high security in mind | |
#pod for the systems that can support this without those programs failing | |
#pod on systems where the extra tests are irrelevant. | |
#pod | |
#pod If you really need to see whether the change has been accepted | |
#pod simply examine the return value of C<safe_level>. | |
#pod | |
#pod $newlevel = File::Temp->safe_level( File::Temp::HIGH ); | |
#pod die "Could not change to high security" | |
#pod if $newlevel != File::Temp::HIGH; | |
#pod | |
#pod Available since 0.05. | |
#pod | |
#pod =cut | |
{ | |
# protect from using the variable itself | |
my $LEVEL = STANDARD; | |
sub safe_level { | |
my $self = shift; | |
if (@_) { | |
my $level = shift; | |
if (($level != STANDARD) && ($level != MEDIUM) && ($level != HIGH)) { | |
carp "safe_level: Specified level ($level) not STANDARD, MEDIUM or HIGH - ignoring\n" if $^W; | |
} else { | |
# Don't allow this on perl 5.005 or earlier | |
if ($] < 5.006 && $level != STANDARD) { | |
# Cant do MEDIUM or HIGH checks | |
croak "Currently requires perl 5.006 or newer to do the safe checks"; | |
} | |
# Check that we are allowed to change level | |
# Silently ignore if we can not. | |
$LEVEL = $level if _can_do_level($level); | |
} | |
} | |
return $LEVEL; | |
} | |
} | |
#pod =item TopSystemUID | |
#pod | |
#pod This is the highest UID on the current system that refers to a root | |
#pod UID. This is used to make sure that the temporary directory is | |
#pod owned by a system UID (C<root>, C<bin>, C<sys> etc) rather than | |
#pod simply by root. | |
#pod | |
#pod This is required since on many unix systems C</tmp> is not owned | |
#pod by root. | |
#pod | |
#pod Default is to assume that any UID less than or equal to 10 is a root | |
#pod UID. | |
#pod | |
#pod File::Temp->top_system_uid(10); | |
#pod my $topid = File::Temp->top_system_uid; | |
#pod | |
#pod This value can be adjusted to reduce security checking if required. | |
#pod The value is only relevant when C<safe_level> is set to MEDIUM or higher. | |
#pod | |
#pod Available since 0.05. | |
#pod | |
#pod =cut | |
{ | |
my $TopSystemUID = 10; | |
$TopSystemUID = 197108 if $^O eq 'interix'; # "Administrator" | |
sub top_system_uid { | |
my $self = shift; | |
if (@_) { | |
my $newuid = shift; | |
croak "top_system_uid: UIDs should be numeric" | |
unless $newuid =~ /^\d+$/s; | |
$TopSystemUID = $newuid; | |
} | |
return $TopSystemUID; | |
} | |
} | |
#pod =item B<$KEEP_ALL> | |
#pod | |
#pod Controls whether temporary files and directories should be retained | |
#pod regardless of any instructions in the program to remove them | |
#pod automatically. This is useful for debugging but should not be used in | |
#pod production code. | |
#pod | |
#pod $File::Temp::KEEP_ALL = 1; | |
#pod | |
#pod Default is for files to be removed as requested by the caller. | |
#pod | |
#pod In some cases, files will only be retained if this variable is true | |
#pod when the file is created. This means that you can not create a temporary | |
#pod file, set this variable and expect the temp file to still be around | |
#pod when the program exits. | |
#pod | |
#pod =item B<$DEBUG> | |
#pod | |
#pod Controls whether debugging messages should be enabled. | |
#pod | |
#pod $File::Temp::DEBUG = 1; | |
#pod | |
#pod Default is for debugging mode to be disabled. | |
#pod | |
#pod Available since 0.15. | |
#pod | |
#pod =back | |
#pod | |
#pod =head1 WARNING | |
#pod | |
#pod For maximum security, endeavour always to avoid ever looking at, | |
#pod touching, or even imputing the existence of the filename. You do not | |
#pod know that that filename is connected to the same file as the handle | |
#pod you have, and attempts to check this can only trigger more race | |
#pod conditions. It's far more secure to use the filehandle alone and | |
#pod dispense with the filename altogether. | |
#pod | |
#pod If you need to pass the handle to something that expects a filename | |
#pod then on a unix system you can use C<"/dev/fd/" . fileno($fh)> for | |
#pod arbitrary programs. Perl code that uses the 2-argument version of | |
#pod C<< open >> can be passed C<< "+<=&" . fileno($fh) >>. Otherwise you | |
#pod will need to pass the filename. You will have to clear the | |
#pod close-on-exec bit on that file descriptor before passing it to another | |
#pod process. | |
#pod | |
#pod use Fcntl qw/F_SETFD F_GETFD/; | |
#pod fcntl($tmpfh, F_SETFD, 0) | |
#pod or die "Can't clear close-on-exec flag on temp fh: $!\n"; | |
#pod | |
#pod =head2 Temporary files and NFS | |
#pod | |
#pod Some problems are associated with using temporary files that reside | |
#pod on NFS file systems and it is recommended that a local filesystem | |
#pod is used whenever possible. Some of the security tests will most probably | |
#pod fail when the temp file is not local. Additionally, be aware that | |
#pod the performance of I/O operations over NFS will not be as good as for | |
#pod a local disk. | |
#pod | |
#pod =head2 Forking | |
#pod | |
#pod In some cases files created by File::Temp are removed from within an | |
#pod END block. Since END blocks are triggered when a child process exits | |
#pod (unless C<POSIX::_exit()> is used by the child) File::Temp takes care | |
#pod to only remove those temp files created by a particular process ID. This | |
#pod means that a child will not attempt to remove temp files created by the | |
#pod parent process. | |
#pod | |
#pod If you are forking many processes in parallel that are all creating | |
#pod temporary files, you may need to reset the random number seed using | |
#pod srand(EXPR) in each child else all the children will attempt to walk | |
#pod through the same set of random file names and may well cause | |
#pod themselves to give up if they exceed the number of retry attempts. | |
#pod | |
#pod =head2 Directory removal | |
#pod | |
#pod Note that if you have chdir'ed into the temporary directory and it is | |
#pod subsequently cleaned up (either in the END block or as part of object | |
#pod destruction), then you will get a warning from File::Path::rmtree(). | |
#pod | |
#pod =head2 Taint mode | |
#pod | |
#pod If you need to run code under taint mode, updating to the latest | |
#pod L<File::Spec> is highly recommended. On Windows, if the directory | |
#pod given by L<File::Spec::tmpdir> isn't writable, File::Temp will attempt | |
#pod to fallback to the user's local application data directory or croak | |
#pod with an error. | |
#pod | |
#pod =head2 BINMODE | |
#pod | |
#pod The file returned by File::Temp will have been opened in binary mode | |
#pod if such a mode is available. If that is not correct, use the C<binmode()> | |
#pod function to change the mode of the filehandle. | |
#pod | |
#pod Note that you can modify the encoding of a file opened by File::Temp | |
#pod also by using C<binmode()>. | |
#pod | |
#pod =head1 HISTORY | |
#pod | |
#pod Originally began life in May 1999 as an XS interface to the system | |
#pod mkstemp() function. In March 2000, the OpenBSD mkstemp() code was | |
#pod translated to Perl for total control of the code's | |
#pod security checking, to ensure the presence of the function regardless of | |
#pod operating system and to help with portability. The module was shipped | |
#pod as a standard part of perl from v5.6.1. | |
#pod | |
#pod Thanks to Tom Christiansen for suggesting that this module | |
#pod should be written and providing ideas for code improvements and | |
#pod security enhancements. | |
#pod | |
#pod =head1 SEE ALSO | |
#pod | |
#pod L<POSIX/tmpnam>, L<POSIX/tmpfile>, L<File::Spec>, L<File::Path> | |
#pod | |
#pod See L<IO::File> and L<File::MkTemp>, L<Apache::TempFile> for | |
#pod different implementations of temporary file handling. | |
#pod | |
#pod See L<File::Tempdir> for an alternative object-oriented wrapper for | |
#pod the C<tempdir> function. | |
#pod | |
#pod =cut | |
package ## hide from PAUSE | |
File::Temp::Dir; | |
our $VERSION = '0.2311'; | |
use File::Path qw/ rmtree /; | |
use strict; | |
use overload '""' => "STRINGIFY", | |
'0+' => \&File::Temp::NUMIFY, | |
fallback => 1; | |
# private class specifically to support tempdir objects | |
# created by File::Temp->newdir | |
# ostensibly the same method interface as File::Temp but without | |
# inheriting all the IO::Seekable methods and other cruft | |
# Read-only - returns the name of the temp directory | |
sub dirname { | |
my $self = shift; | |
return $self->{DIRNAME}; | |
} | |
sub STRINGIFY { | |
my $self = shift; | |
return $self->dirname; | |
} | |
sub unlink_on_destroy { | |
my $self = shift; | |
if (@_) { | |
$self->{CLEANUP} = shift; | |
} | |
return $self->{CLEANUP}; | |
} | |
sub DESTROY { | |
my $self = shift; | |
local($., $@, $!, $^E, $?); | |
if ($self->unlink_on_destroy && | |
$$ == $self->{LAUNCHPID} && !$File::Temp::KEEP_ALL) { | |
if (-d $self->{REALNAME}) { | |
# Some versions of rmtree will abort if you attempt to remove | |
# the directory you are sitting in. We protect that and turn it | |
# into a warning. We do this because this occurs during object | |
# destruction and so can not be caught by the user. | |
eval { rmtree($self->{REALNAME}, $File::Temp::DEBUG, 0); }; | |
warn $@ if ($@ && $^W); | |
} | |
} | |
} | |
1; | |
# vim: ts=2 sts=2 sw=2 et: | |
__END__ | |
=pod | |
=encoding UTF-8 | |
=head1 NAME | |
File::Temp - return name and handle of a temporary file safely | |
=head1 VERSION | |
version 0.2311 | |
=head1 SYNOPSIS | |
use File::Temp qw/ tempfile tempdir /; | |
$fh = tempfile(); | |
($fh, $filename) = tempfile(); | |
($fh, $filename) = tempfile( $template, DIR => $dir); | |
($fh, $filename) = tempfile( $template, SUFFIX => '.dat'); | |
($fh, $filename) = tempfile( $template, TMPDIR => 1 ); | |
binmode( $fh, ":utf8" ); | |
$dir = tempdir( CLEANUP => 1 ); | |
($fh, $filename) = tempfile( DIR => $dir ); | |
Object interface: | |
require File::Temp; | |
use File::Temp (); | |
use File::Temp qw/ :seekable /; | |
$fh = File::Temp->new(); | |
$fname = $fh->filename; | |
$fh = File::Temp->new(TEMPLATE => $template); | |
$fname = $fh->filename; | |
$tmp = File::Temp->new( UNLINK => 0, SUFFIX => '.dat' ); | |
print $tmp "Some data\n"; | |
print "Filename is $tmp\n"; | |
$tmp->seek( 0, SEEK_END ); | |
$dir = File::Temp->newdir(); # CLEANUP => 1 by default | |
The following interfaces are provided for compatibility with | |
existing APIs. They should not be used in new code. | |
MkTemp family: | |
use File::Temp qw/ :mktemp /; | |
($fh, $file) = mkstemp( "tmpfileXXXXX" ); | |
($fh, $file) = mkstemps( "tmpfileXXXXXX", $suffix); | |
$tmpdir = mkdtemp( $template ); | |
$unopened_file = mktemp( $template ); | |
POSIX functions: | |
use File::Temp qw/ :POSIX /; | |
$file = tmpnam(); | |
$fh = tmpfile(); | |
($fh, $file) = tmpnam(); | |
Compatibility functions: | |
$unopened_file = File::Temp::tempnam( $dir, $pfx ); | |
=head1 DESCRIPTION | |
C<File::Temp> can be used to create and open temporary files in a safe | |
way. There is both a function interface and an object-oriented | |
interface. The File::Temp constructor or the tempfile() function can | |
be used to return the name and the open filehandle of a temporary | |
file. The tempdir() function can be used to create a temporary | |
directory. | |
The security aspect of temporary file creation is emphasized such that | |
a filehandle and filename are returned together. This helps guarantee | |
that a race condition can not occur where the temporary file is | |
created by another process between checking for the existence of the | |
file and its opening. Additional security levels are provided to | |
check, for example, that the sticky bit is set on world writable | |
directories. See L<"safe_level"> for more information. | |
For compatibility with popular C library functions, Perl implementations of | |
the mkstemp() family of functions are provided. These are, mkstemp(), | |
mkstemps(), mkdtemp() and mktemp(). | |
Additionally, implementations of the standard L<POSIX|POSIX> | |
tmpnam() and tmpfile() functions are provided if required. | |
Implementations of mktemp(), tmpnam(), and tempnam() are provided, | |
but should be used with caution since they return only a filename | |
that was valid when function was called, so cannot guarantee | |
that the file will not exist by the time the caller opens the filename. | |
Filehandles returned by these functions support the seekable methods. | |
=begin :__INTERNALS | |
=head1 PORTABILITY | |
This section is at the top in order to provide easier access to | |
porters. It is not expected to be rendered by a standard pod | |
formatting tool. Please skip straight to the SYNOPSIS section if you | |
are not trying to port this module to a new platform. | |
This module is designed to be portable across operating systems and it | |
currently supports Unix, VMS, DOS, OS/2, Windows and Mac OS | |
(Classic). When porting to a new OS there are generally three main | |
issues that have to be solved: | |
=over 4 | |
=item * | |
Can the OS unlink an open file? If it can not then the | |
C<_can_unlink_opened_file> method should be modified. | |
=item * | |
Are the return values from C<stat> reliable? By default all the | |
return values from C<stat> are compared when unlinking a temporary | |
file using the filename and the handle. Operating systems other than | |
unix do not always have valid entries in all fields. If utility function | |
C<File::Temp::unlink0> fails then the C<stat> comparison should be | |
modified accordingly. | |
=item * | |
Security. Systems that can not support a test for the sticky bit | |
on a directory can not use the MEDIUM and HIGH security tests. | |
The C<_can_do_level> method should be modified accordingly. | |
=back | |
=end :__INTERNALS | |
=head1 OBJECT-ORIENTED INTERFACE | |
This is the primary interface for interacting with | |
C<File::Temp>. Using the OO interface a temporary file can be created | |
when the object is constructed and the file can be removed when the | |
object is no longer required. | |
Note that there is no method to obtain the filehandle from the | |
C<File::Temp> object. The object itself acts as a filehandle. The object | |
isa C<IO::Handle> and isa C<IO::Seekable> so all those methods are | |
available. | |
Also, the object is configured such that it stringifies to the name of the | |
temporary file and so can be compared to a filename directly. It numifies | |
to the C<refaddr> the same as other handles and so can be compared to other | |
handles with C<==>. | |
$fh eq $filename # as a string | |
$fh != \*STDOUT # as a number | |
Available since 0.14. | |
=over 4 | |
=item B<new> | |
Create a temporary file object. | |
my $tmp = File::Temp->new(); | |
by default the object is constructed as if C<tempfile> | |
was called without options, but with the additional behaviour | |
that the temporary file is removed by the object destructor | |
if UNLINK is set to true (the default). | |
Supported arguments are the same as for C<tempfile>: UNLINK | |
(defaulting to true), DIR, EXLOCK, PERMS and SUFFIX. | |
Additionally, the filename | |
template is specified using the TEMPLATE option. The OPEN option | |
is not supported (the file is always opened). | |
$tmp = File::Temp->new( TEMPLATE => 'tempXXXXX', | |
DIR => 'mydir', | |
SUFFIX => '.dat'); | |
Arguments are case insensitive. | |
Can call croak() if an error occurs. | |
Available since 0.14. | |
TEMPLATE available since 0.23 | |
=item B<newdir> | |
Create a temporary directory using an object oriented interface. | |
$dir = File::Temp->newdir(); | |
By default the directory is deleted when the object goes out of scope. | |
Supports the same options as the C<tempdir> function. Note that directories | |
created with this method default to CLEANUP => 1. | |
$dir = File::Temp->newdir( $template, %options ); | |
A template may be specified either with a leading template or | |
with a TEMPLATE argument. | |
Available since 0.19. | |
TEMPLATE available since 0.23. | |
=item B<filename> | |
Return the name of the temporary file associated with this object | |
(if the object was created using the "new" constructor). | |
$filename = $tmp->filename; | |
This method is called automatically when the object is used as | |
a string. | |
Current API available since 0.14 | |
=item B<dirname> | |
Return the name of the temporary directory associated with this | |
object (if the object was created using the "newdir" constructor). | |
$dirname = $tmpdir->dirname; | |
This method is called automatically when the object is used in string context. | |
=item B<unlink_on_destroy> | |
Control whether the file is unlinked when the object goes out of scope. | |
The file is removed if this value is true and $KEEP_ALL is not. | |
$fh->unlink_on_destroy( 1 ); | |
Default is for the file to be removed. | |
Current API available since 0.15 | |
=item B<DESTROY> | |
When the object goes out of scope, the destructor is called. This | |
destructor will attempt to unlink the file (using L<unlink1|"unlink1">) | |
if the constructor was called with UNLINK set to 1 (the default state | |
if UNLINK is not specified). | |
No error is given if the unlink fails. | |
If the object has been passed to a child process during a fork, the | |
file will be deleted when the object goes out of scope in the parent. | |
For a temporary directory object the directory will be removed unless | |
the CLEANUP argument was used in the constructor (and set to false) or | |
C<unlink_on_destroy> was modified after creation. Note that if a temp | |
directory is your current directory, it cannot be removed - a warning | |
will be given in this case. C<chdir()> out of the directory before | |
letting the object go out of scope. | |
If the global variable $KEEP_ALL is true, the file or directory | |
will not be removed. | |
=back | |
=head1 FUNCTIONS | |
This section describes the recommended interface for generating | |
temporary files and directories. | |
=over 4 | |
=item B<tempfile> | |
This is the basic function to generate temporary files. | |
The behaviour of the file can be changed using various options: | |
$fh = tempfile(); | |
($fh, $filename) = tempfile(); | |
Create a temporary file in the directory specified for temporary | |
files, as specified by the tmpdir() function in L<File::Spec>. | |
($fh, $filename) = tempfile($template); | |
Create a temporary file in the current directory using the supplied | |
template. Trailing `X' characters are replaced with random letters to | |
generate the filename. At least four `X' characters must be present | |
at the end of the template. | |
($fh, $filename) = tempfile($template, SUFFIX => $suffix) | |
Same as previously, except that a suffix is added to the template | |
after the `X' translation. Useful for ensuring that a temporary | |
filename has a particular extension when needed by other applications. | |
But see the WARNING at the end. | |
($fh, $filename) = tempfile($template, DIR => $dir); | |
Translates the template as before except that a directory name | |
is specified. | |
($fh, $filename) = tempfile($template, TMPDIR => 1); | |
Equivalent to specifying a DIR of "File::Spec->tmpdir", writing the file | |
into the same temporary directory as would be used if no template was | |
specified at all. | |
($fh, $filename) = tempfile($template, UNLINK => 1); | |
Return the filename and filehandle as before except that the file is | |
automatically removed when the program exits (dependent on | |
$KEEP_ALL). Default is for the file to be removed if a file handle is | |
requested and to be kept if the filename is requested. In a scalar | |
context (where no filename is returned) the file is always deleted | |
either (depending on the operating system) on exit or when it is | |
closed (unless $KEEP_ALL is true when the temp file is created). | |
Use the object-oriented interface if fine-grained control of when | |
a file is removed is required. | |
If the template is not specified, a template is always | |
automatically generated. This temporary file is placed in tmpdir() | |
(L<File::Spec>) unless a directory is specified explicitly with the | |
DIR option. | |
$fh = tempfile( DIR => $dir ); | |
If called in scalar context, only the filehandle is returned and the | |
file will automatically be deleted when closed on operating systems | |
that support this (see the description of tmpfile() elsewhere in this | |
document). This is the preferred mode of operation, as if you only | |
have a filehandle, you can never create a race condition by fumbling | |
with the filename. On systems that can not unlink an open file or can | |
not mark a file as temporary when it is opened (for example, Windows | |
NT uses the C<O_TEMPORARY> flag) the file is marked for deletion when | |
the program ends (equivalent to setting UNLINK to 1). The C<UNLINK> | |
flag is ignored if present. | |
(undef, $filename) = tempfile($template, OPEN => 0); | |
This will return the filename based on the template but | |
will not open this file. Cannot be used in conjunction with | |
UNLINK set to true. Default is to always open the file | |
to protect from possible race conditions. A warning is issued | |
if warnings are turned on. Consider using the tmpnam() | |
and mktemp() functions described elsewhere in this document | |
if opening the file is not required. | |
To open the temporary filehandle with O_EXLOCK (open with exclusive | |
file lock) use C<< EXLOCK=>1 >>. This is supported only by some | |
operating systems (most notably BSD derived systems). By default | |
EXLOCK will be false. Former C<File::Temp> versions set EXLOCK to | |
true, so to be sure to get an unlocked filehandle also with older | |
versions, explicitly set C<< EXLOCK=>0 >>. | |
($fh, $filename) = tempfile($template, EXLOCK => 1); | |
By default, the temp file is created with 0600 file permissions. | |
Use C<PERMS> to change this: | |
($fh, $filename) = tempfile($template, PERMS => 0666); | |
Options can be combined as required. | |
Will croak() if there is an error. | |
Available since 0.05. | |
UNLINK flag available since 0.10. | |
TMPDIR flag available since 0.19. | |
EXLOCK flag available since 0.19. | |
PERMS flag available since 0.2310. | |
=item B<tempdir> | |
This is the recommended interface for creation of temporary | |
directories. By default the directory will not be removed on exit | |
(that is, it won't be temporary; this behaviour can not be changed | |
because of issues with backwards compatibility). To enable removal | |
either use the CLEANUP option which will trigger removal on program | |
exit, or consider using the "newdir" method in the object interface which | |
will allow the directory to be cleaned up when the object goes out of | |
scope. | |
The behaviour of the function depends on the arguments: | |
$tempdir = tempdir(); | |
Create a directory in tmpdir() (see L<File::Spec|File::Spec>). | |
$tempdir = tempdir( $template ); | |
Create a directory from the supplied template. This template is | |
similar to that described for tempfile(). `X' characters at the end | |
of the template are replaced with random letters to construct the | |
directory name. At least four `X' characters must be in the template. | |
$tempdir = tempdir ( DIR => $dir ); | |
Specifies the directory to use for the temporary directory. | |
The temporary directory name is derived from an internal template. | |
$tempdir = tempdir ( $template, DIR => $dir ); | |
Prepend the supplied directory name to the template. The template | |
should not include parent directory specifications itself. Any parent | |
directory specifications are removed from the template before | |
prepending the supplied directory. | |
$tempdir = tempdir ( $template, TMPDIR => 1 ); | |
Using the supplied template, create the temporary directory in | |
a standard location for temporary files. Equivalent to doing | |
$tempdir = tempdir ( $template, DIR => File::Spec->tmpdir); | |
but shorter. Parent directory specifications are stripped from the | |
template itself. The C<TMPDIR> option is ignored if C<DIR> is set | |
explicitly. Additionally, C<TMPDIR> is implied if neither a template | |
nor a directory are supplied. | |
$tempdir = tempdir( $template, CLEANUP => 1); | |
Create a temporary directory using the supplied template, but | |
attempt to remove it (and all files inside it) when the program | |
exits. Note that an attempt will be made to remove all files from | |
the directory even if they were not created by this module (otherwise | |
why ask to clean it up?). The directory removal is made with | |
the rmtree() function from the L<File::Path|File::Path> module. | |
Of course, if the template is not specified, the temporary directory | |
will be created in tmpdir() and will also be removed at program exit. | |
Will croak() if there is an error. | |
Current API available since 0.05. | |
=back | |
=head1 MKTEMP FUNCTIONS | |
The following functions are Perl implementations of the | |
mktemp() family of temp file generation system calls. | |
=over 4 | |
=item B<mkstemp> | |
Given a template, returns a filehandle to the temporary file and the name | |
of the file. | |
($fh, $name) = mkstemp( $template ); | |
In scalar context, just the filehandle is returned. | |
The template may be any filename with some number of X's appended | |
to it, for example F</tmp/temp.XXXX>. The trailing X's are replaced | |
with unique alphanumeric combinations. | |
Will croak() if there is an error. | |
Current API available since 0.05. | |
=item B<mkstemps> | |
Similar to mkstemp(), except that an extra argument can be supplied | |
with a suffix to be appended to the template. | |
($fh, $name) = mkstemps( $template, $suffix ); | |
For example a template of C<testXXXXXX> and suffix of C<.dat> | |
would generate a file similar to F<testhGji_w.dat>. | |
Returns just the filehandle alone when called in scalar context. | |
Will croak() if there is an error. | |
Current API available since 0.05. | |
=item B<mkdtemp> | |
Create a directory from a template. The template must end in | |
X's that are replaced by the routine. | |
$tmpdir_name = mkdtemp($template); | |
Returns the name of the temporary directory created. | |
Directory must be removed by the caller. | |
Will croak() if there is an error. | |
Current API available since 0.05. | |
=item B<mktemp> | |
Returns a valid temporary filename but does not guarantee | |
that the file will not be opened by someone else. | |
$unopened_file = mktemp($template); | |
Template is the same as that required by mkstemp(). | |
Will croak() if there is an error. | |
Current API available since 0.05. | |
=back | |
=head1 POSIX FUNCTIONS | |
This section describes the re-implementation of the tmpnam() | |
and tmpfile() functions described in L<POSIX> | |
using the mkstemp() from this module. | |
Unlike the L<POSIX|POSIX> implementations, the directory used | |
for the temporary file is not specified in a system include | |
file (C<P_tmpdir>) but simply depends on the choice of tmpdir() | |
returned by L<File::Spec|File::Spec>. On some implementations this | |
location can be set using the C<TMPDIR> environment variable, which | |
may not be secure. | |
If this is a problem, simply use mkstemp() and specify a template. | |
=over 4 | |
=item B<tmpnam> | |
When called in scalar context, returns the full name (including path) | |
of a temporary file (uses mktemp()). The only check is that the file does | |
not already exist, but there is no guarantee that that condition will | |
continue to apply. | |
$file = tmpnam(); | |
When called in list context, a filehandle to the open file and | |
a filename are returned. This is achieved by calling mkstemp() | |
after constructing a suitable template. | |
($fh, $file) = tmpnam(); | |
If possible, this form should be used to prevent possible | |
race conditions. | |
See L<File::Spec/tmpdir> for information on the choice of temporary | |
directory for a particular operating system. | |
Will croak() if there is an error. | |
Current API available since 0.05. | |
=item B<tmpfile> | |
Returns the filehandle of a temporary file. | |
$fh = tmpfile(); | |
The file is removed when the filehandle is closed or when the program | |
exits. No access to the filename is provided. | |
If the temporary file can not be created undef is returned. | |
Currently this command will probably not work when the temporary | |
directory is on an NFS file system. | |
Will croak() if there is an error. | |
Available since 0.05. | |
Returning undef if unable to create file added in 0.12. | |
=back | |
=head1 ADDITIONAL FUNCTIONS | |
These functions are provided for backwards compatibility | |
with common tempfile generation C library functions. | |
They are not exported and must be addressed using the full package | |
name. | |
=over 4 | |
=item B<tempnam> | |
Return the name of a temporary file in the specified directory | |
using a prefix. The file is guaranteed not to exist at the time | |
the function was called, but such guarantees are good for one | |
clock tick only. Always use the proper form of C<sysopen> | |
with C<O_CREAT | O_EXCL> if you must open such a filename. | |
$filename = File::Temp::tempnam( $dir, $prefix ); | |
Equivalent to running mktemp() with $dir/$prefixXXXXXXXX | |
(using unix file convention as an example) | |
Because this function uses mktemp(), it can suffer from race conditions. | |
Will croak() if there is an error. | |
Current API available since 0.05. | |
=back | |
=head1 UTILITY FUNCTIONS | |
Useful functions for dealing with the filehandle and filename. | |
=over 4 | |
=item B<unlink0> | |
Given an open filehandle and the associated filename, make a safe | |
unlink. This is achieved by first checking that the filename and | |
filehandle initially point to the same file and that the number of | |
links to the file is 1 (all fields returned by stat() are compared). | |
Then the filename is unlinked and the filehandle checked once again to | |
verify that the number of links on that file is now 0. This is the | |
closest you can come to making sure that the filename unlinked was the | |
same as the file whose descriptor you hold. | |
unlink0($fh, $path) | |
or die "Error unlinking file $path safely"; | |
Returns false on error but croaks() if there is a security | |
anomaly. The filehandle is not closed since on some occasions this is | |
not required. | |
On some platforms, for example Windows NT, it is not possible to | |
unlink an open file (the file must be closed first). On those | |
platforms, the actual unlinking is deferred until the program ends and | |
good status is returned. A check is still performed to make sure that | |
the filehandle and filename are pointing to the same thing (but not at | |
the time the end block is executed since the deferred removal may not | |
have access to the filehandle). | |
Additionally, on Windows NT not all the fields returned by stat() can | |
be compared. For example, the C<dev> and C<rdev> fields seem to be | |
different. Also, it seems that the size of the file returned by stat() | |
does not always agree, with C<stat(FH)> being more accurate than | |
C<stat(filename)>, presumably because of caching issues even when | |
using autoflush (this is usually overcome by waiting a while after | |
writing to the tempfile before attempting to C<unlink0> it). | |
Finally, on NFS file systems the link count of the file handle does | |
not always go to zero immediately after unlinking. Currently, this | |
command is expected to fail on NFS disks. | |
This function is disabled if the global variable $KEEP_ALL is true | |
and an unlink on open file is supported. If the unlink is to be deferred | |
to the END block, the file is still registered for removal. | |
This function should not be called if you are using the object oriented | |
interface since the it will interfere with the object destructor deleting | |
the file. | |
Available Since 0.05. | |
If can not unlink open file, defer removal until later available since 0.06. | |
=item B<cmpstat> | |
Compare C<stat> of filehandle with C<stat> of provided filename. This | |
can be used to check that the filename and filehandle initially point | |
to the same file and that the number of links to the file is 1 (all | |
fields returned by stat() are compared). | |
cmpstat($fh, $path) | |
or die "Error comparing handle with file"; | |
Returns false if the stat information differs or if the link count is | |
greater than 1. Calls croak if there is a security anomaly. | |
On certain platforms, for example Windows, not all the fields returned by stat() | |
can be compared. For example, the C<dev> and C<rdev> fields seem to be | |
different in Windows. Also, it seems that the size of the file | |
returned by stat() does not always agree, with C<stat(FH)> being more | |
accurate than C<stat(filename)>, presumably because of caching issues | |
even when using autoflush (this is usually overcome by waiting a while | |
after writing to the tempfile before attempting to C<unlink0> it). | |
Not exported by default. | |
Current API available since 0.14. | |
=item B<unlink1> | |
Similar to C<unlink0> except after file comparison using cmpstat, the | |
filehandle is closed prior to attempting to unlink the file. This | |
allows the file to be removed without using an END block, but does | |
mean that the post-unlink comparison of the filehandle state provided | |
by C<unlink0> is not available. | |
unlink1($fh, $path) | |
or die "Error closing and unlinking file"; | |
Usually called from the object destructor when using the OO interface. | |
Not exported by default. | |
This function is disabled if the global variable $KEEP_ALL is true. | |
Can call croak() if there is a security anomaly during the stat() | |
comparison. | |
Current API available since 0.14. | |
=item B<cleanup> | |
Calling this function will cause any temp files or temp directories | |
that are registered for removal to be removed. This happens automatically | |
when the process exits but can be triggered manually if the caller is sure | |
that none of the temp files are required. This method can be registered as | |
an Apache callback. | |
Note that if a temp directory is your current directory, it cannot be | |
removed. C<chdir()> out of the directory first before calling | |
C<cleanup()>. (For the cleanup at program exit when the CLEANUP flag | |
is set, this happens automatically.) | |
On OSes where temp files are automatically removed when the temp file | |
is closed, calling this function will have no effect other than to remove | |
temporary directories (which may include temporary files). | |
File::Temp::cleanup(); | |
Not exported by default. | |
Current API available since 0.15. | |
=back | |
=head1 PACKAGE VARIABLES | |
These functions control the global state of the package. | |
=over 4 | |
=item B<safe_level> | |
Controls the lengths to which the module will go to check the safety of the | |
temporary file or directory before proceeding. | |
Options are: | |
=over 8 | |
=item STANDARD | |
Do the basic security measures to ensure the directory exists and is | |
writable, that temporary files are opened only if they do not already | |
exist, and that possible race conditions are avoided. Finally the | |
L<unlink0|"unlink0"> function is used to remove files safely. | |
=item MEDIUM | |
In addition to the STANDARD security, the output directory is checked | |
to make sure that it is owned either by root or the user running the | |
program. If the directory is writable by group or by other, it is then | |
checked to make sure that the sticky bit is set. | |
Will not work on platforms that do not support the C<-k> test | |
for sticky bit. | |
=item HIGH | |
In addition to the MEDIUM security checks, also check for the | |
possibility of ``chown() giveaway'' using the L<POSIX|POSIX> | |
sysconf() function. If this is a possibility, each directory in the | |
path is checked in turn for safeness, recursively walking back to the | |
root directory. | |
For platforms that do not support the L<POSIX|POSIX> | |
C<_PC_CHOWN_RESTRICTED> symbol (for example, Windows NT) it is | |
assumed that ``chown() giveaway'' is possible and the recursive test | |
is performed. | |
=back | |
The level can be changed as follows: | |
File::Temp->safe_level( File::Temp::HIGH ); | |
The level constants are not exported by the module. | |
Currently, you must be running at least perl v5.6.0 in order to | |
run with MEDIUM or HIGH security. This is simply because the | |
safety tests use functions from L<Fcntl|Fcntl> that are not | |
available in older versions of perl. The problem is that the version | |
number for Fcntl is the same in perl 5.6.0 and in 5.005_03 even though | |
they are different versions. | |
On systems that do not support the HIGH or MEDIUM safety levels | |
(for example Win NT or OS/2) any attempt to change the level will | |
be ignored. The decision to ignore rather than raise an exception | |
allows portable programs to be written with high security in mind | |
for the systems that can support this without those programs failing | |
on systems where the extra tests are irrelevant. | |
If you really need to see whether the change has been accepted | |
simply examine the return value of C<safe_level>. | |
$newlevel = File::Temp->safe_level( File::Temp::HIGH ); | |
die "Could not change to high security" | |
if $newlevel != File::Temp::HIGH; | |
Available since 0.05. | |
=item TopSystemUID | |
This is the highest UID on the current system that refers to a root | |
UID. This is used to make sure that the temporary directory is | |
owned by a system UID (C<root>, C<bin>, C<sys> etc) rather than | |
simply by root. | |
This is required since on many unix systems C</tmp> is not owned | |
by root. | |
Default is to assume that any UID less than or equal to 10 is a root | |
UID. | |
File::Temp->top_system_uid(10); | |
my $topid = File::Temp->top_system_uid; | |
This value can be adjusted to reduce security checking if required. | |
The value is only relevant when C<safe_level> is set to MEDIUM or higher. | |
Available since 0.05. | |
=item B<$KEEP_ALL> | |
Controls whether temporary files and directories should be retained | |
regardless of any instructions in the program to remove them | |
automatically. This is useful for debugging but should not be used in | |
production code. | |
$File::Temp::KEEP_ALL = 1; | |
Default is for files to be removed as requested by the caller. | |
In some cases, files will only be retained if this variable is true | |
when the file is created. This means that you can not create a temporary | |
file, set this variable and expect the temp file to still be around | |
when the program exits. | |
=item B<$DEBUG> | |
Controls whether debugging messages should be enabled. | |
$File::Temp::DEBUG = 1; | |
Default is for debugging mode to be disabled. | |
Available since 0.15. | |
=back | |
=head1 WARNING | |
For maximum security, endeavour always to avoid ever looking at, | |
touching, or even imputing the existence of the filename. You do not | |
know that that filename is connected to the same file as the handle | |
you have, and attempts to check this can only trigger more race | |
conditions. It's far more secure to use the filehandle alone and | |
dispense with the filename altogether. | |
If you need to pass the handle to something that expects a filename | |
then on a unix system you can use C<"/dev/fd/" . fileno($fh)> for | |
arbitrary programs. Perl code that uses the 2-argument version of | |
C<< open >> can be passed C<< "+<=&" . fileno($fh) >>. Otherwise you | |
will need to pass the filename. You will have to clear the | |
close-on-exec bit on that file descriptor before passing it to another | |
process. | |
use Fcntl qw/F_SETFD F_GETFD/; | |
fcntl($tmpfh, F_SETFD, 0) | |
or die "Can't clear close-on-exec flag on temp fh: $!\n"; | |
=head2 Temporary files and NFS | |
Some problems are associated with using temporary files that reside | |
on NFS file systems and it is recommended that a local filesystem | |
is used whenever possible. Some of the security tests will most probably | |
fail when the temp file is not local. Additionally, be aware that | |
the performance of I/O operations over NFS will not be as good as for | |
a local disk. | |
=head2 Forking | |
In some cases files created by File::Temp are removed from within an | |
END block. Since END blocks are triggered when a child process exits | |
(unless C<POSIX::_exit()> is used by the child) File::Temp takes care | |
to only remove those temp files created by a particular process ID. This | |
means that a child will not attempt to remove temp files created by the | |
parent process. | |
If you are forking many processes in parallel that are all creating | |
temporary files, you may need to reset the random number seed using | |
srand(EXPR) in each child else all the children will attempt to walk | |
through the same set of random file names and may well cause | |
themselves to give up if they exceed the number of retry attempts. | |
=head2 Directory removal | |
Note that if you have chdir'ed into the temporary directory and it is | |
subsequently cleaned up (either in the END block or as part of object | |
destruction), then you will get a warning from File::Path::rmtree(). | |
=head2 Taint mode | |
If you need to run code under taint mode, updating to the latest | |
L<File::Spec> is highly recommended. On Windows, if the directory | |
given by L<File::Spec::tmpdir> isn't writable, File::Temp will attempt | |
to fallback to the user's local application data directory or croak | |
with an error. | |
=head2 BINMODE | |
The file returned by File::Temp will have been opened in binary mode | |
if such a mode is available. If that is not correct, use the C<binmode()> | |
function to change the mode of the filehandle. | |
Note that you can modify the encoding of a file opened by File::Temp | |
also by using C<binmode()>. | |
=head1 HISTORY | |
Originally began life in May 1999 as an XS interface to the system | |
mkstemp() function. In March 2000, the OpenBSD mkstemp() code was | |
translated to Perl for total control of the code's | |
security checking, to ensure the presence of the function regardless of | |
operating system and to help with portability. The module was shipped | |
as a standard part of perl from v5.6.1. | |
Thanks to Tom Christiansen for suggesting that this module | |
should be written and providing ideas for code improvements and | |
security enhancements. | |
=head1 SEE ALSO | |
L<POSIX/tmpnam>, L<POSIX/tmpfile>, L<File::Spec>, L<File::Path> | |
See L<IO::File> and L<File::MkTemp>, L<Apache::TempFile> for | |
different implementations of temporary file handling. | |
See L<File::Tempdir> for an alternative object-oriented wrapper for | |
the C<tempdir> function. | |
=for Pod::Coverage STRINGIFY NUMIFY top_system_uid | |
=head1 SUPPORT | |
Bugs may be submitted through L<the RT bug tracker|https://rt.cpan.org/Public/Dist/Display.html?Name=File-Temp> | |
(or L<[email protected]|mailto:[email protected]>). | |
There is also a mailing list available for users of this distribution, at | |
L<http://lists.perl.org/list/cpan-workers.html>. | |
There is also an irc channel available for users of this distribution, at | |
L<C<#toolchain> on C<irc.perl.org>|irc://irc.perl.org/#toolchain>. | |
=head1 AUTHOR | |
Tim Jenness <[email protected]> | |
=head1 CONTRIBUTORS | |
=for stopwords Tim Jenness Karen Etheridge David Golden Slaven Rezic mohawk2 Roy Ivy III Peter Rabbitson Olivier Mengué John Acklam Gim Yee Nicolas R Brian Mowrey Dagfinn Ilmari Mannsåker Steinbrunner Ed Avis Guillem Jover James E. Keenan Kevin Ryde Ben Tilly | |
=over 4 | |
=item * | |
Tim Jenness <[email protected]> | |
=item * | |
Karen Etheridge <[email protected]> | |
=item * | |
David Golden <[email protected]> | |
=item * | |
Slaven Rezic <[email protected]> | |
=item * | |
mohawk2 <[email protected]> | |
=item * | |
Roy Ivy III <[email protected]> | |
=item * | |
Peter Rabbitson <[email protected]> | |
=item * | |
Olivier Mengué <[email protected]> | |
=item * | |
Peter John Acklam <[email protected]> | |
=item * | |
Tim Gim Yee <[email protected]> | |
=item * | |
Nicolas R <[email protected]> | |
=item * | |
Brian Mowrey <[email protected]> | |
=item * | |
Dagfinn Ilmari Mannsåker <[email protected]> | |
=item * | |
David Steinbrunner <[email protected]> | |
=item * | |
Ed Avis <[email protected]> | |
=item * | |
Guillem Jover <[email protected]> | |
=item * | |
James E. Keenan <[email protected]> | |
=item * | |
Kevin Ryde <[email protected]> | |
=item * | |
Ben Tilly <[email protected]> | |
=back | |
=head1 COPYRIGHT AND LICENSE | |
This software is copyright (c) 2020 by Tim Jenness and the UK Particle Physics and Astronomy Research Council. | |
This is free software; you can redistribute it and/or modify it under | |
the same terms as the Perl 5 programming language system itself. | |
=cut | |