/usr/share/perl5/IO/ScalarArray.pm is in libio-stringy-perl 2.110-5.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 | package IO::ScalarArray;
=head1 NAME
IO::ScalarArray - IO:: interface for reading/writing an array of scalars
=head1 SYNOPSIS
Perform I/O on strings, using the basic OO interface...
use IO::ScalarArray;
@data = ("My mes", "sage:\n");
### Open a handle on an array, and append to it:
$AH = new IO::ScalarArray \@data;
$AH->print("Hello");
$AH->print(", world!\nBye now!\n");
print "The array is now: ", @data, "\n";
### Open a handle on an array, read it line-by-line, then close it:
$AH = new IO::ScalarArray \@data;
while (defined($_ = $AH->getline)) {
print "Got line: $_";
}
$AH->close;
### Open a handle on an array, and slurp in all the lines:
$AH = new IO::ScalarArray \@data;
print "All lines:\n", $AH->getlines;
### Get the current position (either of two ways):
$pos = $AH->getpos;
$offset = $AH->tell;
### Set the current position (either of two ways):
$AH->setpos($pos);
$AH->seek($offset, 0);
### Open an anonymous temporary array:
$AH = new IO::ScalarArray;
$AH->print("Hi there!");
print "I printed: ", @{$AH->aref}, "\n"; ### get at value
Don't like OO for your I/O? No problem.
Thanks to the magic of an invisible tie(), the following now
works out of the box, just as it does with IO::Handle:
use IO::ScalarArray;
@data = ("My mes", "sage:\n");
### Open a handle on an array, and append to it:
$AH = new IO::ScalarArray \@data;
print $AH "Hello";
print $AH ", world!\nBye now!\n";
print "The array is now: ", @data, "\n";
### Open a handle on a string, read it line-by-line, then close it:
$AH = new IO::ScalarArray \@data;
while (<$AH>) {
print "Got line: $_";
}
close $AH;
### Open a handle on a string, and slurp in all the lines:
$AH = new IO::ScalarArray \@data;
print "All lines:\n", <$AH>;
### Get the current position (WARNING: requires 5.6):
$offset = tell $AH;
### Set the current position (WARNING: requires 5.6):
seek $AH, $offset, 0;
### Open an anonymous temporary scalar:
$AH = new IO::ScalarArray;
print $AH "Hi there!";
print "I printed: ", @{$AH->aref}, "\n"; ### get at value
And for you folks with 1.x code out there: the old tie() style still works,
though this is I<unnecessary and deprecated>:
use IO::ScalarArray;
### Writing to a scalar...
my @a;
tie *OUT, 'IO::ScalarArray', \@a;
print OUT "line 1\nline 2\n", "line 3\n";
print "Array is now: ", @a, "\n"
### Reading and writing an anonymous scalar...
tie *OUT, 'IO::ScalarArray';
print OUT "line 1\nline 2\n", "line 3\n";
tied(OUT)->seek(0,0);
while (<OUT>) {
print "Got line: ", $_;
}
=head1 DESCRIPTION
This class is part of the IO::Stringy distribution;
see L<IO::Stringy> for change log and general information.
The IO::ScalarArray class implements objects which behave just like
IO::Handle (or FileHandle) objects, except that you may use them
to write to (or read from) arrays of scalars. Logically, an
array of scalars defines an in-core "file" whose contents are
the concatenation of the scalars in the array. The handles created by
this class are automatically tiehandle'd (though please see L<"WARNINGS">
for information relevant to your Perl version).
For writing large amounts of data with individual print() statements,
this class is likely to be more efficient than IO::Scalar.
Basically, this:
my @a;
$AH = new IO::ScalarArray \@a;
$AH->print("Hel", "lo, "); ### OO style
$AH->print("world!\n"); ### ditto
Or this:
my @a;
$AH = new IO::ScalarArray \@a;
print $AH "Hel", "lo, "; ### non-OO style
print $AH "world!\n"; ### ditto
Causes @a to be set to the following array of 3 strings:
( "Hel" ,
"lo, " ,
"world!\n" )
See L<IO::Scalar> and compare with this class.
=head1 PUBLIC INTERFACE
=cut
use Carp;
use strict;
use vars qw($VERSION @ISA);
use IO::Handle;
# The package version, both in 1.23 style *and* usable by MakeMaker:
$VERSION = "2.110";
# Inheritance:
@ISA = qw(IO::Handle);
require IO::WrapTie and push @ISA, 'IO::WrapTie::Slave' if ($] >= 5.004);
#==============================
=head2 Construction
=over 4
=cut
#------------------------------
=item new [ARGS...]
I<Class method.>
Return a new, unattached array handle.
If any arguments are given, they're sent to open().
=cut
sub new {
my $proto = shift;
my $class = ref($proto) || $proto;
my $self = bless \do { local *FH }, $class;
tie *$self, $class, $self;
$self->open(@_); ### open on anonymous by default
$self;
}
sub DESTROY {
shift->close;
}
#------------------------------
=item open [ARRAYREF]
I<Instance method.>
Open the array handle on a new array, pointed to by ARRAYREF.
If no ARRAYREF is given, a "private" array is created to hold
the file data.
Returns the self object on success, undefined on error.
=cut
sub open {
my ($self, $aref) = @_;
### Sanity:
defined($aref) or do {my @a; $aref = \@a};
(ref($aref) eq "ARRAY") or croak "open needs a ref to a array";
### Setup:
$self->setpos([0,0]);
*$self->{AR} = $aref;
$self;
}
#------------------------------
=item opened
I<Instance method.>
Is the array handle opened on something?
=cut
sub opened {
*{shift()}->{AR};
}
#------------------------------
=item close
I<Instance method.>
Disassociate the array handle from its underlying array.
Done automatically on destroy.
=cut
sub close {
my $self = shift;
%{*$self} = ();
1;
}
=back
=cut
#==============================
=head2 Input and output
=over 4
=cut
#------------------------------
=item flush
I<Instance method.>
No-op, provided for OO compatibility.
=cut
sub flush { "0 but true" }
#------------------------------
=item getc
I<Instance method.>
Return the next character, or undef if none remain.
This does a read(1), which is somewhat costly.
=cut
sub getc {
my $buf = '';
($_[0]->read($buf, 1) ? $buf : undef);
}
#------------------------------
=item getline
I<Instance method.>
Return the next line, or undef on end of data.
Can safely be called in an array context.
Currently, lines are delimited by "\n".
=cut
sub getline {
my $self = shift;
my ($str, $line) = (undef, '');
### Minimal impact implementation!
### We do the fast fast thing (no regexps) if using the
### classic input record separator.
### Case 1: $/ is undef: slurp all...
if (!defined($/)) {
return undef if ($self->eof);
### Get the rest of the current string, followed by remaining strings:
my $ar = *$self->{AR};
my @slurp = (
substr($ar->[*$self->{Str}], *$self->{Pos}),
@$ar[(1 + *$self->{Str}) .. $#$ar ]
);
### Seek to end:
$self->_setpos_to_eof;
return join('', @slurp);
}
### Case 2: $/ is "\n":
elsif ($/ eq "\012") {
### Until we hit EOF (or exitted because of a found line):
until ($self->eof) {
### If at end of current string, go fwd to next one (won't be EOF):
if ($self->_eos) {++*$self->{Str}, *$self->{Pos}=0};
### Get ref to current string in array, and set internal pos mark:
$str = \(*$self->{AR}[*$self->{Str}]); ### get current string
pos($$str) = *$self->{Pos}; ### start matching from here
### Get from here to either \n or end of string, and add to line:
$$str =~ m/\G(.*?)((\n)|\Z)/g; ### match to 1st \n or EOS
$line .= $1.$2; ### add it
*$self->{Pos} += length($1.$2); ### move fwd by len matched
return $line if $3; ### done, got line with "\n"
}
return ($line eq '') ? undef : $line; ### return undef if EOF
}
### Case 3: $/ is ref to int. Bail out.
elsif (ref($/)) {
croak '$/ given as a ref to int; currently unsupported';
}
### Case 4: $/ is either "" (paragraphs) or something weird...
### Bail for now.
else {
croak '$/ as given is currently unsupported';
}
}
#------------------------------
=item getlines
I<Instance method.>
Get all remaining lines.
It will croak() if accidentally called in a scalar context.
=cut
sub getlines {
my $self = shift;
wantarray or croak("can't call getlines in scalar context!");
my ($line, @lines);
push @lines, $line while (defined($line = $self->getline));
@lines;
}
#------------------------------
=item print ARGS...
I<Instance method.>
Print ARGS to the underlying array.
Currently, this always causes a "seek to the end of the array"
and generates a new array entry. This may change in the future.
=cut
sub print {
my $self = shift;
push @{*$self->{AR}}, join('', @_) . (defined($\) ? $\ : ""); ### add the data
$self->_setpos_to_eof;
1;
}
#------------------------------
=item read BUF, NBYTES, [OFFSET];
I<Instance method.>
Read some bytes from the array.
Returns the number of bytes actually read, 0 on end-of-file, undef on error.
=cut
sub read {
my $self = $_[0];
### we must use $_[1] as a ref
my $n = $_[2];
my $off = $_[3] || 0;
### print "getline\n";
my $justread;
my $len;
($off ? substr($_[1], $off) : $_[1]) = '';
### Stop when we have zero bytes to go, or when we hit EOF:
my @got;
until (!$n or $self->eof) {
### If at end of current string, go forward to next one (won't be EOF):
if ($self->_eos) {
++*$self->{Str};
*$self->{Pos} = 0;
}
### Get longest possible desired substring of current string:
$justread = substr(*$self->{AR}[*$self->{Str}], *$self->{Pos}, $n);
$len = length($justread);
push @got, $justread;
$n -= $len;
*$self->{Pos} += $len;
}
$_[1] .= join('', @got);
return length($_[1])-$off;
}
#------------------------------
=item write BUF, NBYTES, [OFFSET];
I<Instance method.>
Write some bytes into the array.
=cut
sub write {
my $self = $_[0];
my $n = $_[2];
my $off = $_[3] || 0;
my $data = substr($_[1], $n, $off);
$n = length($data);
$self->print($data);
return $n;
}
=back
=cut
#==============================
=head2 Seeking/telling and other attributes
=over 4
=cut
#------------------------------
=item autoflush
I<Instance method.>
No-op, provided for OO compatibility.
=cut
sub autoflush {}
#------------------------------
=item binmode
I<Instance method.>
No-op, provided for OO compatibility.
=cut
sub binmode {}
#------------------------------
=item clearerr
I<Instance method.> Clear the error and EOF flags. A no-op.
=cut
sub clearerr { 1 }
#------------------------------
=item eof
I<Instance method.> Are we at end of file?
=cut
sub eof {
### print "checking EOF [*$self->{Str}, *$self->{Pos}]\n";
### print "SR = ", $#{*$self->{AR}}, "\n";
return 0 if (*{$_[0]}->{Str} < $#{*{$_[0]}->{AR}}); ### before EOA
return 1 if (*{$_[0]}->{Str} > $#{*{$_[0]}->{AR}}); ### after EOA
### ### at EOA, past EOS:
((*{$_[0]}->{Str} == $#{*{$_[0]}->{AR}}) && ($_[0]->_eos));
}
#------------------------------
#
# _eos
#
# I<Instance method, private.> Are we at end of the CURRENT string?
#
sub _eos {
(*{$_[0]}->{Pos} >= length(*{$_[0]}->{AR}[*{$_[0]}->{Str}])); ### past last char
}
#------------------------------
=item seek POS,WHENCE
I<Instance method.>
Seek to a given position in the stream.
Only a WHENCE of 0 (SEEK_SET) is supported.
=cut
sub seek {
my ($self, $pos, $whence) = @_;
### Seek:
if ($whence == 0) { $self->_seek_set($pos); }
elsif ($whence == 1) { $self->_seek_cur($pos); }
elsif ($whence == 2) { $self->_seek_end($pos); }
else { croak "bad seek whence ($whence)" }
return 1;
}
#------------------------------
#
# _seek_set POS
#
# Instance method, private.
# Seek to $pos relative to start:
#
sub _seek_set {
my ($self, $pos) = @_;
### Advance through array until done:
my $istr = 0;
while (($pos >= 0) && ($istr < scalar(@{*$self->{AR}}))) {
if (length(*$self->{AR}[$istr]) > $pos) { ### it's in this string!
return $self->setpos([$istr, $pos]);
}
else { ### it's in next string
$pos -= length(*$self->{AR}[$istr++]); ### move forward one string
}
}
### If we reached this point, pos is at or past end; zoom to EOF:
return $self->_setpos_to_eof;
}
#------------------------------
#
# _seek_cur POS
#
# Instance method, private.
# Seek to $pos relative to current position.
#
sub _seek_cur {
my ($self, $pos) = @_;
$self->_seek_set($self->tell + $pos);
}
#------------------------------
#
# _seek_end POS
#
# Instance method, private.
# Seek to $pos relative to end.
# We actually seek relative to beginning, which is simple.
#
sub _seek_end {
my ($self, $pos) = @_;
$self->_seek_set($self->_tell_eof + $pos);
}
#------------------------------
=item tell
I<Instance method.>
Return the current position in the stream, as a numeric offset.
=cut
sub tell {
my $self = shift;
my $off = 0;
my ($s, $str_s);
for ($s = 0; $s < *$self->{Str}; $s++) { ### count all "whole" scalars
defined($str_s = *$self->{AR}[$s]) or $str_s = '';
###print STDERR "COUNTING STRING $s (". length($str_s) . ")\n";
$off += length($str_s);
}
###print STDERR "COUNTING POS ($self->{Pos})\n";
return ($off += *$self->{Pos}); ### plus the final, partial one
}
#------------------------------
#
# _tell_eof
#
# Instance method, private.
# Get position of EOF, as a numeric offset.
# This is identical to the size of the stream - 1.
#
sub _tell_eof {
my $self = shift;
my $len = 0;
foreach (@{*$self->{AR}}) { $len += length($_) }
$len;
}
#------------------------------
=item setpos POS
I<Instance method.>
Seek to a given position in the array, using the opaque getpos() value.
Don't expect this to be a number.
=cut
sub setpos {
my ($self, $pos) = @_;
(ref($pos) eq 'ARRAY') or
die "setpos: only use a value returned by getpos!\n";
(*$self->{Str}, *$self->{Pos}) = @$pos;
}
#------------------------------
#
# _setpos_to_eof
#
# Fast-forward to EOF.
#
sub _setpos_to_eof {
my $self = shift;
$self->setpos([scalar(@{*$self->{AR}}), 0]);
}
#------------------------------
=item getpos
I<Instance method.>
Return the current position in the array, as an opaque value.
Don't expect this to be a number.
=cut
sub getpos {
[*{$_[0]}->{Str}, *{$_[0]}->{Pos}];
}
#------------------------------
=item aref
I<Instance method.>
Return a reference to the underlying array.
=cut
sub aref {
*{shift()}->{AR};
}
=back
=cut
#------------------------------
# Tied handle methods...
#------------------------------
### Conventional tiehandle interface:
sub TIEHANDLE { (defined($_[1]) && UNIVERSAL::isa($_[1],"IO::ScalarArray"))
? $_[1]
: shift->new(@_) }
sub GETC { shift->getc(@_) }
sub PRINT { shift->print(@_) }
sub PRINTF { shift->print(sprintf(shift, @_)) }
sub READ { shift->read(@_) }
sub READLINE { wantarray ? shift->getlines(@_) : shift->getline(@_) }
sub WRITE { shift->write(@_); }
sub CLOSE { shift->close(@_); }
sub SEEK { shift->seek(@_); }
sub TELL { shift->tell(@_); }
sub EOF { shift->eof(@_); }
#------------------------------------------------------------
1;
__END__
# SOME PRIVATE NOTES:
#
# * The "current position" is the position before the next
# character to be read/written.
#
# * Str gives the string index of the current position, 0-based
#
# * Pos gives the offset within AR[Str], 0-based.
#
# * Inital pos is [0,0]. After print("Hello"), it is [1,0].
=head1 WARNINGS
Perl's TIEHANDLE spec was incomplete prior to 5.005_57;
it was missing support for C<seek()>, C<tell()>, and C<eof()>.
Attempting to use these functions with an IO::ScalarArray will not work
prior to 5.005_57. IO::ScalarArray will not have the relevant methods
invoked; and even worse, this kind of bug can lie dormant for a while.
If you turn warnings on (via C<$^W> or C<perl -w>),
and you see something like this...
attempt to seek on unopened filehandle
...then you are probably trying to use one of these functions
on an IO::ScalarArray with an old Perl. The remedy is to simply
use the OO version; e.g.:
$AH->seek(0,0); ### GOOD: will work on any 5.005
seek($AH,0,0); ### WARNING: will only work on 5.005_57 and beyond
=head1 VERSION
$Id: ScalarArray.pm,v 1.7 2005/02/10 21:21:53 dfs Exp $
=head1 AUTHOR
=head2 Primary Maintainer
David F. Skoll (F<dfs@roaringpenguin.com>).
=head2 Principal author
Eryq (F<eryq@zeegee.com>).
President, ZeeGee Software Inc (F<http://www.zeegee.com>).
=head2 Other contributors
Thanks to the following individuals for their invaluable contributions
(if I've forgotten or misspelled your name, please email me!):
I<Andy Glew,>
for suggesting C<getc()>.
I<Brandon Browning,>
for suggesting C<opened()>.
I<Eric L. Brine,>
for his offset-using read() and write() implementations.
I<Doug Wilson,>
for the IO::Handle inheritance and automatic tie-ing.
=cut
#------------------------------
1;
|