package Test::Builder::IO::Scalar; =head1 NAME Test::Builder::IO::Scalar - A copy of IO::Scalar for Test::Builder =head1 DESCRIPTION This is a copy of L which ships with L to support scalar references as filehandles on Perl 5.6. Newer versions of Perl simply use C's built in support. L can not have dependencies on other modules without careful consideration, so its simply been copied into the distribution. =head1 COPYRIGHT and LICENSE This file came from the "IO-stringy" Perl5 toolkit. Copyright (c) 1996 by Eryq. All rights reserved. Copyright (c) 1999,2001 by ZeeGee Software Inc. All rights reserved. This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself. =cut # This is copied code, I don't care. ##no critic use Carp; use strict; use vars qw($VERSION @ISA); use IO::Handle; use 5.005; ### The package version, both in 1.23 style *and* usable by MakeMaker: $VERSION = "2.113"; ### Inheritance: @ISA = qw(IO::Handle); #============================== =head2 Construction =over 4 =cut #------------------------------ =item new [ARGS...] I Return a new, unattached scalar 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 $self; } sub DESTROY { shift->close; } #------------------------------ =item open [SCALARREF] I Open the scalar handle on a new scalar, pointed to by SCALARREF. If no SCALARREF is given, a "private" scalar is created to hold the file data. Returns the self object on success, undefined on error. =cut sub open { my ($self, $sref) = @_; ### Sanity: defined($sref) or do {my $s = ''; $sref = \$s}; (ref($sref) eq "SCALAR") or croak "open() needs a ref to a scalar"; ### Setup: *$self->{Pos} = 0; ### seek position *$self->{SR} = $sref; ### scalar reference $self; } #------------------------------ =item opened I Is the scalar handle opened on something? =cut sub opened { *{shift()}->{SR}; } #------------------------------ =item close I Disassociate the scalar handle from its underlying scalar. Done automatically on destroy. =cut sub close { my $self = shift; %{*$self} = (); 1; } =back =cut #============================== =head2 Input and output =over 4 =cut #------------------------------ =item flush I No-op, provided for OO compatibility. =cut sub flush { "0 but true" } #------------------------------ =item getc I Return the next character, or undef if none remain. =cut sub getc { my $self = shift; ### Return undef right away if at EOF; else, move pos forward: return undef if $self->eof; substr(${*$self->{SR}}, *$self->{Pos}++, 1); } #------------------------------ =item getline I Return the next line, or undef on end of string. Can safely be called in an array context. Currently, lines are delimited by "\n". =cut sub getline { my $self = shift; ### Return undef right away if at EOF: return undef if $self->eof; ### Get next line: my $sr = *$self->{SR}; my $i = *$self->{Pos}; ### Start matching at this point. ### Minimal impact implementation! ### We do the fast fast thing (no regexps) if using the ### classic input record separator. ### Case 1: $/ is undef: slurp all... if (!defined($/)) { *$self->{Pos} = length $$sr; return substr($$sr, $i); } ### Case 2: $/ is "\n": zoom zoom zoom... elsif ($/ eq "\012") { ### Seek ahead for "\n"... yes, this really is faster than regexps. my $len = length($$sr); for (; $i < $len; ++$i) { last if ord (substr ($$sr, $i, 1)) == 10; } ### Extract the line: my $line; if ($i < $len) { ### We found a "\n": $line = substr ($$sr, *$self->{Pos}, $i - *$self->{Pos} + 1); *$self->{Pos} = $i+1; ### Remember where we finished up. } else { ### No "\n"; slurp the remainder: $line = substr ($$sr, *$self->{Pos}, $i - *$self->{Pos}); *$self->{Pos} = $len; } return $line; } ### Case 3: $/ is ref to int. Do fixed-size records. ### (Thanks to Dominique Quatravaux.) elsif (ref($/)) { my $len = length($$sr); my $i = ${$/} + 0; my $line = substr ($$sr, *$self->{Pos}, $i); *$self->{Pos} += $i; *$self->{Pos} = $len if (*$self->{Pos} > $len); return $line; } ### Case 4: $/ is either "" (paragraphs) or something weird... ### This is Graham's general-purpose stuff, which might be ### a tad slower than Case 2 for typical data, because ### of the regexps. else { pos($$sr) = $i; ### If in paragraph mode, skip leading lines (and update i!): length($/) or (($$sr =~ m/\G\n*/g) and ($i = pos($$sr))); ### If we see the separator in the buffer ahead... if (length($/) ? $$sr =~ m,\Q$/\E,g ### (ordinary sep) TBD: precomp! : $$sr =~ m,\n\n,g ### (a paragraph) ) { *$self->{Pos} = pos $$sr; return substr($$sr, $i, *$self->{Pos}-$i); } ### Else if no separator remains, just slurp the rest: else { *$self->{Pos} = length $$sr; return substr($$sr, $i); } } } #------------------------------ =item getlines I 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 Print ARGS to the underlying scalar. B this continues to always cause a seek to the end of the string, but if you perform seek()s and tell()s, it is still safer to explicitly seek-to-end before subsequent print()s. =cut sub print { my $self = shift; *$self->{Pos} = length(${*$self->{SR}} .= join('', @_) . (defined($\) ? $\ : "")); 1; } sub _unsafe_print { my $self = shift; my $append = join('', @_) . $\; ${*$self->{SR}} .= $append; *$self->{Pos} += length($append); 1; } sub _old_print { my $self = shift; ${*$self->{SR}} .= join('', @_) . $\; *$self->{Pos} = length(${*$self->{SR}}); 1; } #------------------------------ =item read BUF, NBYTES, [OFFSET] I Read some bytes from the scalar. Returns the number of bytes actually read, 0 on end-of-file, undef on error. =cut sub read { my $self = $_[0]; my $n = $_[2]; my $off = $_[3] || 0; my $read = substr(${*$self->{SR}}, *$self->{Pos}, $n); $n = length($read); *$self->{Pos} += $n; ($off ? substr($_[1], $off) : $_[1]) = $read; return $n; } #------------------------------ =item write BUF, NBYTES, [OFFSET] I Write some bytes to the scalar. =cut sub write { my $self = $_[0]; my $n = $_[2]; my $off = $_[3] || 0; my $data = substr($_[1], $off, $n); $n = length($data); $self->print($data); return $n; } #------------------------------ =item sysread BUF, LEN, [OFFSET] I Read some bytes from the scalar. Returns the number of bytes actually read, 0 on end-of-file, undef on error. =cut sub sysread { my $self = shift; $self->read(@_); } #------------------------------ =item syswrite BUF, NBYTES, [OFFSET] I Write some bytes to the scalar. =cut sub syswrite { my $self = shift; $self->write(@_); } =back =cut #============================== =head2 Seeking/telling and other attributes =over 4 =cut #------------------------------ =item autoflush I No-op, provided for OO compatibility. =cut sub autoflush {} #------------------------------ =item binmode I No-op, provided for OO compatibility. =cut sub binmode {} #------------------------------ =item clearerr I Clear the error and EOF flags. A no-op. =cut sub clearerr { 1 } #------------------------------ =item eof I Are we at end of file? =cut sub eof { my $self = shift; (*$self->{Pos} >= length(${*$self->{SR}})); } #------------------------------ =item seek OFFSET, WHENCE I Seek to a given position in the stream. =cut sub seek { my ($self, $pos, $whence) = @_; my $eofpos = length(${*$self->{SR}}); ### Seek: if ($whence == 0) { *$self->{Pos} = $pos } ### SEEK_SET elsif ($whence == 1) { *$self->{Pos} += $pos } ### SEEK_CUR elsif ($whence == 2) { *$self->{Pos} = $eofpos + $pos} ### SEEK_END else { croak "bad seek whence ($whence)" } ### Fixup: if (*$self->{Pos} < 0) { *$self->{Pos} = 0 } if (*$self->{Pos} > $eofpos) { *$self->{Pos} = $eofpos } return 1; } #------------------------------ =item sysseek OFFSET, WHENCE I Identical to C, I =cut sub sysseek { my $self = shift; $self->seek (@_); } #------------------------------ =item tell I Return the current position in the stream, as a numeric offset. =cut sub tell { *{shift()}->{Pos} } #------------------------------ =item use_RS [YESNO] I B Obey the current setting of $/, like IO::Handle does? Default is false in 1.x, but cold-welded true in 2.x and later. =cut sub use_RS { my ($self, $yesno) = @_; carp "use_RS is deprecated and ignored; \$/ is always consulted\n"; } #------------------------------ =item setpos POS I Set the current position, using the opaque value returned by C. =cut sub setpos { shift->seek($_[0],0) } #------------------------------ =item getpos I Return the current position in the string, as an opaque object. =cut *getpos = \&tell; #------------------------------ =item sref I Return a reference to the underlying scalar. =cut sub sref { *{shift()}->{SR} } #------------------------------ # Tied handle methods... #------------------------------ # Conventional tiehandle interface: sub TIEHANDLE { ((defined($_[1]) && UNIVERSAL::isa($_[1], __PACKAGE__)) ? $_[1] : shift->new(@_)); } sub GETC { shift->getc(@_) } sub PRINT { shift->print(@_) } sub PRINTF { shift->print(sprintf(shift, @_)) } sub READ { shift->read(@_) } sub READLINE { wantarray ? shift->getlines(@_) : shift->getline(@_) } sub WRITE { shift->write(@_); } sub CLOSE { shift->close(@_); } sub SEEK { shift->seek(@_); } sub TELL { shift->tell(@_); } sub EOF { shift->eof(@_); } #------------------------------------------------------------ 1; __END__ =back =cut =head1 WARNINGS Perl's TIEHANDLE spec was incomplete prior to 5.005_57; it was missing support for C, C, and C. Attempting to use these functions with an IO::Scalar will not work prior to 5.005_57. IO::Scalar will not have the relevant methods invoked; and even worse, this kind of bug can lie dormant for a while. If you turn warnings on (via C<$^W> or C), 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::Scalar with an old Perl. The remedy is to simply use the OO version; e.g.: $SH->seek(0,0); ### GOOD: will work on any 5.005 seek($SH,0,0); ### WARNING: will only work on 5.005_57 and beyond =head1 VERSION $Id: Scalar.pm,v 1.6 2005/02/10 21:21:53 dfs Exp $ =head1 AUTHORS =head2 Primary Maintainer David F. Skoll (F). =head2 Principal author Eryq (F). President, ZeeGee Software Inc (F). =head2 Other contributors The full set of contributors always includes the folks mentioned in L. But just the same, special thanks to the following individuals for their invaluable contributions (if I've forgotten or misspelled your name, please email me!): I for contributing C. I for suggesting C. I for finding and fixing the bug in C. I for his offset-using read() and write() implementations. I for his patches to massively improve the performance of C and add C and C. I for stringification and inheritance improvements, and sundry good ideas. I for the IO::Handle inheritance and automatic tie-ing. =head1 SEE ALSO L, which is quite similar but which was designed more-recently and with an IO::Handle-like interface in mind, so you could mix OO- and native-filehandle usage without using tied(). I as of version 2.x, these classes all work like their IO::Handle counterparts, so we have comparable functionality to IO::String. =cut