xref: /openbsd-src/gnu/usr.bin/perl/lib/File/Copy.pm (revision 799f675f6700f14e59124f9825c723e9f2ce19dc)
1# File/Copy.pm. Written in 1994 by Aaron Sherman <ajs@ajs.com>. This
2# source code has been placed in the public domain by the author.
3# Please be kind and preserve the documentation.
4#
5# Additions copyright 1996 by Charles Bailey.  Permission is granted
6# to distribute the revised code under the same terms as Perl itself.
7
8package File::Copy;
9
10use 5.006;
11use strict;
12use warnings;
13use Carp;
14use File::Spec;
15use Config;
16our(@ISA, @EXPORT, @EXPORT_OK, $VERSION, $Too_Big, $Syscopy_is_copy);
17sub copy;
18sub syscopy;
19sub cp;
20sub mv;
21
22# Note that this module implements only *part* of the API defined by
23# the File/Copy.pm module of the File-Tools-2.0 package.  However, that
24# package has not yet been updated to work with Perl 5.004, and so it
25# would be a Bad Thing for the CPAN module to grab it and replace this
26# module.  Therefore, we set this module's version higher than 2.0.
27$VERSION = '2.09';
28
29require Exporter;
30@ISA = qw(Exporter);
31@EXPORT = qw(copy move);
32@EXPORT_OK = qw(cp mv);
33
34$Too_Big = 1024 * 1024 * 2;
35
36my $macfiles;
37if ($^O eq 'MacOS') {
38	$macfiles = eval { require Mac::MoreFiles };
39	warn 'Mac::MoreFiles could not be loaded; using non-native syscopy'
40		if $@ && $^W;
41}
42
43sub _catname {
44    my($from, $to) = @_;
45    if (not defined &basename) {
46	require File::Basename;
47	import  File::Basename 'basename';
48    }
49
50    if ($^O eq 'MacOS') {
51	# a partial dir name that's valid only in the cwd (e.g. 'tmp')
52	$to = ':' . $to if $to !~ /:/;
53    }
54
55    return File::Spec->catfile($to, basename($from));
56}
57
58sub copy {
59    croak("Usage: copy(FROM, TO [, BUFFERSIZE]) ")
60      unless(@_ == 2 || @_ == 3);
61
62    my $from = shift;
63    my $to = shift;
64
65    my $from_a_handle = (ref($from)
66			 ? (ref($from) eq 'GLOB'
67			    || UNIVERSAL::isa($from, 'GLOB')
68                            || UNIVERSAL::isa($from, 'IO::Handle'))
69			 : (ref(\$from) eq 'GLOB'));
70    my $to_a_handle =   (ref($to)
71			 ? (ref($to) eq 'GLOB'
72			    || UNIVERSAL::isa($to, 'GLOB')
73                            || UNIVERSAL::isa($to, 'IO::Handle'))
74			 : (ref(\$to) eq 'GLOB'));
75
76    if ($from eq $to) { # works for references, too
77	carp("'$from' and '$to' are identical (not copied)");
78        # The "copy" was a success as the source and destination contain
79        # the same data.
80        return 1;
81    }
82
83    if ((($Config{d_symlink} && $Config{d_readlink}) || $Config{d_link}) &&
84	!($^O eq 'MSWin32' || $^O eq 'os2' || $^O eq 'vms')) {
85	my @fs = stat($from);
86	if (@fs) {
87	    my @ts = stat($to);
88	    if (@ts && $fs[0] == $ts[0] && $fs[1] == $ts[1]) {
89		carp("'$from' and '$to' are identical (not copied)");
90                return 0;
91	    }
92	}
93    }
94
95    if (!$from_a_handle && !$to_a_handle && -d $to && ! -d $from) {
96	$to = _catname($from, $to);
97    }
98
99    if (defined &syscopy && !$Syscopy_is_copy
100	&& !$to_a_handle
101	&& !($from_a_handle && $^O eq 'os2' )	# OS/2 cannot handle handles
102	&& !($from_a_handle && $^O eq 'mpeix')	# and neither can MPE/iX.
103	&& !($from_a_handle && $^O eq 'MSWin32')
104	&& !($from_a_handle && $^O eq 'MacOS')
105	&& !($from_a_handle && $^O eq 'NetWare')
106       )
107    {
108	return syscopy($from, $to);
109    }
110
111    my $closefrom = 0;
112    my $closeto = 0;
113    my ($size, $status, $r, $buf);
114    local($\) = '';
115
116    my $from_h;
117    if ($from_a_handle) {
118       $from_h = $from;
119    } else {
120	$from = _protect($from) if $from =~ /^\s/s;
121       $from_h = \do { local *FH };
122       open($from_h, "< $from\0") or goto fail_open1;
123       binmode $from_h or die "($!,$^E)";
124	$closefrom = 1;
125    }
126
127    my $to_h;
128    if ($to_a_handle) {
129       $to_h = $to;
130    } else {
131	$to = _protect($to) if $to =~ /^\s/s;
132       $to_h = \do { local *FH };
133       open($to_h,"> $to\0") or goto fail_open2;
134       binmode $to_h or die "($!,$^E)";
135	$closeto = 1;
136    }
137
138    if (@_) {
139	$size = shift(@_) + 0;
140	croak("Bad buffer size for copy: $size\n") unless ($size > 0);
141    } else {
142	$size = tied(*$from_h) ? 0 : -s $from_h || 0;
143	$size = 1024 if ($size < 512);
144	$size = $Too_Big if ($size > $Too_Big);
145    }
146
147    $! = 0;
148    for (;;) {
149	my ($r, $w, $t);
150       defined($r = sysread($from_h, $buf, $size))
151	    or goto fail_inner;
152	last unless $r;
153	for ($w = 0; $w < $r; $w += $t) {
154           $t = syswrite($to_h, $buf, $r - $w, $w)
155		or goto fail_inner;
156	}
157    }
158
159    close($to_h) || goto fail_open2 if $closeto;
160    close($from_h) || goto fail_open1 if $closefrom;
161
162    # Use this idiom to avoid uninitialized value warning.
163    return 1;
164
165    # All of these contortions try to preserve error messages...
166  fail_inner:
167    if ($closeto) {
168	$status = $!;
169	$! = 0;
170       close $to_h;
171	$! = $status unless $!;
172    }
173  fail_open2:
174    if ($closefrom) {
175	$status = $!;
176	$! = 0;
177       close $from_h;
178	$! = $status unless $!;
179    }
180  fail_open1:
181    return 0;
182}
183
184sub move {
185    croak("Usage: move(FROM, TO) ") unless @_ == 2;
186
187    my($from,$to) = @_;
188
189    my($fromsz,$tosz1,$tomt1,$tosz2,$tomt2,$sts,$ossts);
190
191    if (-d $to && ! -d $from) {
192	$to = _catname($from, $to);
193    }
194
195    ($tosz1,$tomt1) = (stat($to))[7,9];
196    $fromsz = -s $from;
197    if ($^O eq 'os2' and defined $tosz1 and defined $fromsz) {
198      # will not rename with overwrite
199      unlink $to;
200    }
201    return 1 if rename $from, $to;
202
203    # Did rename return an error even though it succeeded, because $to
204    # is on a remote NFS file system, and NFS lost the server's ack?
205    return 1 if defined($fromsz) && !-e $from &&           # $from disappeared
206                (($tosz2,$tomt2) = (stat($to))[7,9]) &&    # $to's there
207                ($tosz1 != $tosz2 or $tomt1 != $tomt2) &&  #   and changed
208                $tosz2 == $fromsz;                         # it's all there
209
210    ($tosz1,$tomt1) = (stat($to))[7,9];  # just in case rename did something
211
212    {
213        local $@;
214        eval {
215            local $SIG{__DIE__};
216            copy($from,$to) or die;
217            my($atime, $mtime) = (stat($from))[8,9];
218            utime($atime, $mtime, $to);
219            unlink($from)   or die;
220        };
221        return 1 unless $@;
222    }
223    ($sts,$ossts) = ($! + 0, $^E + 0);
224
225    ($tosz2,$tomt2) = ((stat($to))[7,9],0,0) if defined $tomt1;
226    unlink($to) if !defined($tomt1) or $tomt1 != $tomt2 or $tosz1 != $tosz2;
227    ($!,$^E) = ($sts,$ossts);
228    return 0;
229}
230
231*cp = \&copy;
232*mv = \&move;
233
234
235if ($^O eq 'MacOS') {
236    *_protect = sub { MacPerl::MakeFSSpec($_[0]) };
237} else {
238    *_protect = sub { "./$_[0]" };
239}
240
241# &syscopy is an XSUB under OS/2
242unless (defined &syscopy) {
243    if ($^O eq 'VMS') {
244	*syscopy = \&rmscopy;
245    } elsif ($^O eq 'mpeix') {
246	*syscopy = sub {
247	    return 0 unless @_ == 2;
248	    # Use the MPE cp program in order to
249	    # preserve MPE file attributes.
250	    return system('/bin/cp', '-f', $_[0], $_[1]) == 0;
251	};
252    } elsif ($^O eq 'MSWin32') {
253	*syscopy = sub {
254	    return 0 unless @_ == 2;
255	    return Win32::CopyFile(@_, 1);
256	};
257    } elsif ($macfiles) {
258	*syscopy = sub {
259	    my($from, $to) = @_;
260	    my($dir, $toname);
261
262	    return 0 unless -e $from;
263
264	    if ($to =~ /(.*:)([^:]+):?$/) {
265		($dir, $toname) = ($1, $2);
266	    } else {
267		($dir, $toname) = (":", $to);
268	    }
269
270	    unlink($to);
271	    Mac::MoreFiles::FSpFileCopy($from, $dir, $toname, 1);
272	};
273    } else {
274	$Syscopy_is_copy = 1;
275	*syscopy = \&copy;
276    }
277}
278
2791;
280
281__END__
282
283=head1 NAME
284
285File::Copy - Copy files or filehandles
286
287=head1 SYNOPSIS
288
289	use File::Copy;
290
291	copy("file1","file2") or die "Copy failed: $!";
292	copy("Copy.pm",\*STDOUT);
293	move("/dev1/fileA","/dev2/fileB");
294
295	use File::Copy "cp";
296
297	$n = FileHandle->new("/a/file","r");
298	cp($n,"x");
299
300=head1 DESCRIPTION
301
302The File::Copy module provides two basic functions, C<copy> and
303C<move>, which are useful for getting the contents of a file from
304one place to another.
305
306=over 4
307
308=item *
309
310The C<copy> function takes two
311parameters: a file to copy from and a file to copy to. Either
312argument may be a string, a FileHandle reference or a FileHandle
313glob. Obviously, if the first argument is a filehandle of some
314sort, it will be read from, and if it is a file I<name> it will
315be opened for reading. Likewise, the second argument will be
316written to (and created if need be).  Trying to copy a file on top
317of itself is a fatal error.
318
319B<Note that passing in
320files as handles instead of names may lead to loss of information
321on some operating systems; it is recommended that you use file
322names whenever possible.>  Files are opened in binary mode where
323applicable.  To get a consistent behaviour when copying from a
324filehandle to a file, use C<binmode> on the filehandle.
325
326An optional third parameter can be used to specify the buffer
327size used for copying. This is the number of bytes from the
328first file, that wil be held in memory at any given time, before
329being written to the second file. The default buffer size depends
330upon the file, but will generally be the whole file (up to 2Mb), or
3311k for filehandles that do not reference files (eg. sockets).
332
333You may use the syntax C<use File::Copy "cp"> to get at the
334"cp" alias for this function. The syntax is I<exactly> the same.
335
336=item *
337
338The C<move> function also takes two parameters: the current name
339and the intended name of the file to be moved.  If the destination
340already exists and is a directory, and the source is not a
341directory, then the source file will be renamed into the directory
342specified by the destination.
343
344If possible, move() will simply rename the file.  Otherwise, it copies
345the file to the new location and deletes the original.  If an error occurs
346during this copy-and-delete process, you may be left with a (possibly partial)
347copy of the file under the destination name.
348
349You may use the "mv" alias for this function in the same way that
350you may use the "cp" alias for C<copy>.
351
352=back
353
354File::Copy also provides the C<syscopy> routine, which copies the
355file specified in the first parameter to the file specified in the
356second parameter, preserving OS-specific attributes and file
357structure.  For Unix systems, this is equivalent to the simple
358C<copy> routine, which doesn't preserve OS-specific attributes.  For
359VMS systems, this calls the C<rmscopy> routine (see below).  For OS/2
360systems, this calls the C<syscopy> XSUB directly. For Win32 systems,
361this calls C<Win32::CopyFile>.
362
363On Mac OS (Classic), C<syscopy> calls C<Mac::MoreFiles::FSpFileCopy>,
364if available.
365
366=head2 Special behaviour if C<syscopy> is defined (OS/2, VMS and Win32)
367
368If both arguments to C<copy> are not file handles,
369then C<copy> will perform a "system copy" of
370the input file to a new output file, in order to preserve file
371attributes, indexed file structure, I<etc.>  The buffer size
372parameter is ignored.  If either argument to C<copy> is a
373handle to an opened file, then data is copied using Perl
374operators, and no effort is made to preserve file attributes
375or record structure.
376
377The system copy routine may also be called directly under VMS and OS/2
378as C<File::Copy::syscopy> (or under VMS as C<File::Copy::rmscopy>, which
379is the routine that does the actual work for syscopy).
380
381=over 4
382
383=item rmscopy($from,$to[,$date_flag])
384
385The first and second arguments may be strings, typeglobs, typeglob
386references, or objects inheriting from IO::Handle;
387they are used in all cases to obtain the
388I<filespec> of the input and output files, respectively.  The
389name and type of the input file are used as defaults for the
390output file, if necessary.
391
392A new version of the output file is always created, which
393inherits the structure and RMS attributes of the input file,
394except for owner and protections (and possibly timestamps;
395see below).  All data from the input file is copied to the
396output file; if either of the first two parameters to C<rmscopy>
397is a file handle, its position is unchanged.  (Note that this
398means a file handle pointing to the output file will be
399associated with an old version of that file after C<rmscopy>
400returns, not the newly created version.)
401
402The third parameter is an integer flag, which tells C<rmscopy>
403how to handle timestamps.  If it is E<lt> 0, none of the input file's
404timestamps are propagated to the output file.  If it is E<gt> 0, then
405it is interpreted as a bitmask: if bit 0 (the LSB) is set, then
406timestamps other than the revision date are propagated; if bit 1
407is set, the revision date is propagated.  If the third parameter
408to C<rmscopy> is 0, then it behaves much like the DCL COPY command:
409if the name or type of the output file was explicitly specified,
410then no timestamps are propagated, but if they were taken implicitly
411from the input filespec, then all timestamps other than the
412revision date are propagated.  If this parameter is not supplied,
413it defaults to 0.
414
415Like C<copy>, C<rmscopy> returns 1 on success.  If an error occurs,
416it sets C<$!>, deletes the output file, and returns 0.
417
418=back
419
420=head1 RETURN
421
422All functions return 1 on success, 0 on failure.
423$! will be set if an error was encountered.
424
425=head1 NOTES
426
427=over 4
428
429=item *
430
431On Mac OS (Classic), the path separator is ':', not '/', and the
432current directory is denoted as ':', not '.'. You should be careful
433about specifying relative pathnames. While a full path always begins
434with a volume name, a relative pathname should always begin with a
435':'.  If specifying a volume name only, a trailing ':' is required.
436
437E.g.
438
439  copy("file1", "tmp");        # creates the file 'tmp' in the current directory
440  copy("file1", ":tmp:");      # creates :tmp:file1
441  copy("file1", ":tmp");       # same as above
442  copy("file1", "tmp");        # same as above, if 'tmp' is a directory (but don't do
443                               # that, since it may cause confusion, see example #1)
444  copy("file1", "tmp:file1");  # error, since 'tmp:' is not a volume
445  copy("file1", ":tmp:file1"); # ok, partial path
446  copy("file1", "DataHD:");    # creates DataHD:file1
447
448  move("MacintoshHD:fileA", "DataHD:fileB"); # moves (don't copies) files from one
449                                             # volume to another
450
451=back
452
453=head1 AUTHOR
454
455File::Copy was written by Aaron Sherman I<E<lt>ajs@ajs.comE<gt>> in 1995,
456and updated by Charles Bailey I<E<lt>bailey@newman.upenn.eduE<gt>> in 1996.
457
458=cut
459
460