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authorPerl 5 Porters <perl5-porters@africa.nicoh.com>1996-02-02 18:52:27 -0800
committerLarry Wall <lwall@sems.com>1996-02-02 18:52:27 -0800
commitc07a80fdfe3926b5eb0585b674aa5d1f57b32ade (patch)
tree6d56135571eb9ea6635748469bdaf72ad481247a /lib/FileHandle.pm
parent91b7def858c29dac014df40946a128c06b3aa2ed (diff)
downloadperl-c07a80fdfe3926b5eb0585b674aa5d1f57b32ade.tar.gz
perl5.002beta3
[editor's note: no patch file was found for this release, so no fine-grained changes] I can't find the password for our ftp server, so I had to drop it into ftp://ftp.sems.com/pub/incoming/perl5.002b3.tar.gz, which is a drop directory you can't ls. The current plan is that Andy is gonna whack on this a little more, and then release a gamma in a few days when he's happy with it. So don't get carried away. This is now *late* beta. In other words, have less than the appropriate amount of fun. :-) Larry
Diffstat (limited to 'lib/FileHandle.pm')
-rw-r--r--lib/FileHandle.pm390
1 files changed, 265 insertions, 125 deletions
diff --git a/lib/FileHandle.pm b/lib/FileHandle.pm
index cbc6efbc6c..93a3088886 100644
--- a/lib/FileHandle.pm
+++ b/lib/FileHandle.pm
@@ -1,25 +1,80 @@
package FileHandle;
-# Note that some additional FileHandle methods are defined in POSIX.pm.
-
=head1 NAME
FileHandle - supply object methods for filehandles
-cacheout - keep more files open than the system permits
-
=head1 SYNOPSIS
use FileHandle;
- autoflush STDOUT 1;
- cacheout($path);
- print $path @data;
+ $fh = new FileHandle;
+ if ($fh->open "< file") {
+ print <$fh>;
+ $fh->close;
+ }
+
+ $fh = new FileHandle "> FOO";
+ if (defined $fh) {
+ print $fh "bar\n";
+ $fh->close;
+ }
+
+ $fh = new FileHandle "file", "r";
+ if (defined $fh) {
+ print <$fh>;
+ undef $fh; # automatically closes the file
+ }
+
+ $fh = new FileHandle "file", O_WRONLY|O_APPEND;
+ if (defined $fh) {
+ print $fh "corge\n";
+ undef $fh; # automatically closes the file
+ }
+
+ ($readfh, $writefh) = FileHandle::pipe;
+ autoflush STDOUT 1;
+
=head1 DESCRIPTION
-See L<perlvar> for complete descriptions of each of the following supported C<FileHandle>
-methods:
+C<FileHandle::new> creates a C<FileHandle>, which is a reference to a
+newly created symbol (see the C<Symbol> package). If it receives any
+parameters, they are passed to C<FileHandle::open>; if the open fails,
+the C<FileHandle> object is destroyed. Otherwise, it is returned to
+the caller.
+
+C<FileHandle::new_from_fd> creates a C<FileHandle> like C<new> does.
+It requires two parameters, which are passed to C<FileHandle::fdopen>;
+if the fdopen fails, the C<FileHandle> object is destroyed.
+Otherwise, it is returned to the caller.
+
+C<FileHandle::open> accepts one parameter or two. With one parameter,
+it is just a front end for the built-in C<open> function. With two
+parameters, the first parameter is a filename that may include
+whitespace or other special characters, and the second parameter is
+the open mode in either Perl form (">", "+<", etc.) or POSIX form
+("w", "r+", etc.).
+
+C<FileHandle::fdopen> is like C<open> except that its first parameter
+is not a filename but rather a file handle name, a FileHandle object,
+or a file descriptor number.
+
+See L<perlfunc> for complete descriptions of each of the following
+supported C<FileHandle> methods, which are just front ends for the
+corresponding built-in functions:
+
+ close
+ fileno
+ getc
+ gets
+ eof
+ clearerr
+ seek
+ tell
+
+See L<perlvar> for complete descriptions of each of the following
+supported C<FileHandle> methods:
autoflush
output_field_separator
@@ -48,9 +103,9 @@ See L<perlfunc/printf>.
=item $fh->getline
-This works like <$fh> described in L<perlop/"I/O Operators"> except that it's more readable
-and can be safely called in an array context but still
-returns just one line.
+This works like <$fh> described in L<perlop/"I/O Operators">
+except that it's more readable and can be safely called in an
+array context but still returns just one line.
=item $fh->getlines
@@ -60,12 +115,6 @@ It will also croak() if accidentally called in a scalar context.
=back
-=head2 The cacheout() Library
-
-The cacheout() function will make sure that there's a filehandle
-open for writing available as the pathname you give it. It automatically
-closes and re-opens files if you exceed your system file descriptor maximum.
-
=head1 SEE ALSO
L<perlfunc>,
@@ -74,15 +123,6 @@ L<POSIX/"FileHandle">
=head1 BUGS
-F<sys/param.h> lies with its C<NOFILE> define on some systems,
-so you may have to set $cacheout::maxopen yourself.
-
-Some of the methods that set variables (like format_name()) don't
-seem to work.
-
-The POSIX functions that create FileHandle methods should be
-in this module instead.
-
Due to backwards compatibility, all filehandles resemble objects
of class C<FileHandle>, or actually classes derived from that class.
They actually aren't. Which means you can't derive your own
@@ -91,12 +131,20 @@ class from C<FileHandle> and inherit those methods.
=cut
require 5.000;
-use English;
use Carp;
-use Exporter;
+use Fcntl;
+use Symbol;
+use English;
+use SelectSaver;
+
+require Exporter;
+require DynaLoader;
+@ISA = qw(Exporter DynaLoader);
+
+@EXPORT = (@Fcntl::EXPORT,
+ qw(_IOFBF _IOLBF _IONBF));
-@ISA = qw(Exporter);
-@EXPORT = qw(
+@EXPORT_OK = qw(
autoflush
output_field_separator
output_record_separator
@@ -114,173 +162,265 @@ use Exporter;
printf
getline
getlines
-
- cacheout
);
+
+################################################
+## Interaction with the XS.
+##
+
+bootstrap FileHandle;
+
+sub AUTOLOAD {
+ if ($AUTOLOAD =~ /::(_?[a-z])/) {
+ $AutoLoader::AUTOLOAD = $AUTOLOAD;
+ goto &AutoLoader::AUTOLOAD
+ }
+ my $constname = $AUTOLOAD;
+ $constname =~ s/.*:://;
+ my $val = constant($constname);
+ defined $val or croak "$constname is not a valid FileHandle macro";
+ *$AUTOLOAD = sub { $val };
+ goto &$AUTOLOAD;
+}
+
+
+################################################
+## Constructors, destructors.
+##
+
+sub new {
+ @_ >= 1 && @_ <= 3 or croak 'usage: new FileHandle [FILENAME [,MODE]]';
+ my $class = shift;
+ my $fh = gensym;
+ if (@_) {
+ FileHandle::open($fh, @_)
+ or return undef;
+ }
+ bless $fh, $class;
+}
+
+sub new_from_fd {
+ @_ == 3 or croak 'usage: new_from_fd FileHandle FD, MODE';
+ my $class = shift;
+ my $fh = gensym;
+ FileHandle::fdopen($fh, @_)
+ or return undef;
+ bless $fh, $class;
+}
+
+sub DESTROY {
+ my ($fh) = @_;
+ close($fh);
+}
+
+################################################
+## Open and close.
+##
+
+sub pipe {
+ @_ and croak 'usage: FileHandle::pipe()';
+ my $readfh = new FileHandle;
+ my $writefh = new FileHandle;
+ pipe($readfh, $writefh)
+ or return undef;
+ ($readfh, $writefh);
+}
+
+sub _open_mode_string {
+ my ($mode) = @_;
+ $mode =~ /^\+?(<|>>?)$/
+ or $mode =~ s/^r(\+?)$/$1</
+ or $mode =~ s/^w(\+?)$/$1>/
+ or $mode =~ s/^a(\+?)$/$1>>/
+ or croak "FileHandle: bad open mode: $mode";
+ $mode;
+}
+
+sub open {
+ @_ >= 2 && @_ <= 4 or croak 'usage: $fh->open(FILENAME [,MODE [,PERMS]])';
+ my ($fh, $file) = @_;
+ if (@_ > 2) {
+ my ($mode, $perms) = @_[2, 3];
+ if ($mode =~ /^\d+$/) {
+ defined $perms or $perms = 0666;
+ return sysopen($fh, $file, $mode, $perms);
+ }
+ $file = "./" . $file unless $file =~ m#^/#;
+ $file = _open_mode_string($mode) . " $file\0";
+ }
+ open($fh, $file);
+}
+
+sub fdopen {
+ @_ == 3 or croak 'usage: $fh->fdopen(FD, MODE)';
+ my ($fh, $fd, $mode) = @_;
+ if (ref($fd) =~ /GLOB\(/) {
+ # It's a glob reference; remove the star from its name.
+ ($fd = "".$$fd) =~ s/^\*//;
+ } elsif ($fd =~ m#^\d+$#) {
+ # It's an FD number; prefix with "=".
+ $fd = "=$fd";
+ }
+ open($fh, _open_mode_string($mode) . '&' . $fd);
+}
+
+sub close {
+ @_ == 1 or croak 'usage: $fh->close()';
+ close($_[0]);
+}
+
+################################################
+## Normal I/O functions.
+##
+
+sub fileno {
+ @_ == 1 or croak 'usage: $fh->fileno()';
+ fileno($_[0]);
+}
+
+sub getc {
+ @_ == 1 or croak 'usage: $fh->getc()';
+ getc($_[0]);
+}
+
+sub gets {
+ @_ == 1 or croak 'usage: $fh->gets()';
+ my ($handle) = @_;
+ scalar <$handle>;
+}
+
+sub eof {
+ @_ == 1 or croak 'usage: $fh->eof()';
+ eof($_[0]);
+}
+
+sub clearerr {
+ @_ == 1 or croak 'usage: $fh->clearerr()';
+ seek($_[0], 0, 1);
+}
+
+sub seek {
+ @_ == 3 or croak 'usage: $fh->seek(POS, WHENCE)';
+ seek($_[0], $_[1], $_[2]);
+}
+
+sub tell {
+ @_ == 1 or croak 'usage: $fh->tell()';
+ tell($_[0]);
+}
+
sub print {
- local($this) = shift;
+ @_ or croak 'usage: $fh->print([ARGS])';
+ my $this = shift;
print $this @_;
}
sub printf {
- local($this) = shift;
+ @_ or croak 'usage: $fh->printf([ARGS])';
+ my $this = shift;
printf $this @_;
}
sub getline {
- local($this) = shift;
- croak "usage: FileHandle::getline()" if @_;
+ @_ == 1 or croak 'usage: $fh->getline';
+ my $this = shift;
return scalar <$this>;
}
sub getlines {
- local($this) = shift;
- croak "usage: FileHandle::getline()" if @_;
- croak "can't call FileHandle::getlines in a scalar context" if wantarray;
+ @_ == 1 or croak 'usage: $fh->getline()';
+ my $this = shift;
+ wantarray or croak "Can't call FileHandle::getlines in a scalar context";
return <$this>;
-}
+}
+
+################################################
+## State modification functions.
+##
sub autoflush {
- local($old) = select($_[0]);
- local($prev) = $OUTPUT_AUTOFLUSH;
+ my $old = new SelectSaver qualify($_[0], caller);
+ my $prev = $OUTPUT_AUTOFLUSH;
$OUTPUT_AUTOFLUSH = @_ > 1 ? $_[1] : 1;
- select($old);
$prev;
}
sub output_field_separator {
- local($old) = select($_[0]);
- local($prev) = $OUTPUT_FIELD_SEPARATOR;
+ my $old = new SelectSaver qualify($_[0], caller);
+ my $prev = $OUTPUT_FIELD_SEPARATOR;
$OUTPUT_FIELD_SEPARATOR = $_[1] if @_ > 1;
- select($old);
$prev;
}
sub output_record_separator {
- local($old) = select($_[0]);
- local($prev) = $OUTPUT_RECORD_SEPARATOR;
+ my $old = new SelectSaver qualify($_[0], caller);
+ my $prev = $OUTPUT_RECORD_SEPARATOR;
$OUTPUT_RECORD_SEPARATOR = $_[1] if @_ > 1;
- select($old);
$prev;
}
sub input_record_separator {
- local($old) = select($_[0]);
- local($prev) = $INPUT_RECORD_SEPARATOR;
+ my $old = new SelectSaver qualify($_[0], caller);
+ my $prev = $INPUT_RECORD_SEPARATOR;
$INPUT_RECORD_SEPARATOR = $_[1] if @_ > 1;
- select($old);
$prev;
}
sub input_line_number {
- local($old) = select($_[0]);
- local($prev) = $INPUT_LINE_NUMBER;
+ my $old = new SelectSaver qualify($_[0], caller);
+ my $prev = $INPUT_LINE_NUMBER;
$INPUT_LINE_NUMBER = $_[1] if @_ > 1;
- select($old);
$prev;
}
sub format_page_number {
- local($old) = select($_[0]);
- local($prev) = $FORMAT_PAGE_NUMBER;
+ my $old = new SelectSaver qualify($_[0], caller);
+ my $prev = $FORMAT_PAGE_NUMBER;
$FORMAT_PAGE_NUMBER = $_[1] if @_ > 1;
- select($old);
$prev;
}
sub format_lines_per_page {
- local($old) = select($_[0]);
- local($prev) = $FORMAT_LINES_PER_PAGE;
+ my $old = new SelectSaver qualify($_[0], caller);
+ my $prev = $FORMAT_LINES_PER_PAGE;
$FORMAT_LINES_PER_PAGE = $_[1] if @_ > 1;
- select($old);
$prev;
}
sub format_lines_left {
- local($old) = select($_[0]);
- local($prev) = $FORMAT_LINES_LEFT;
+ my $old = new SelectSaver qualify($_[0], caller);
+ my $prev = $FORMAT_LINES_LEFT;
$FORMAT_LINES_LEFT = $_[1] if @_ > 1;
- select($old);
$prev;
}
sub format_name {
- local($old) = select($_[0]);
- local($prev) = $FORMAT_NAME;
- $FORMAT_NAME = $_[1] if @_ > 1;
- select($old);
+ my $old = new SelectSaver qualify($_[0], caller);
+ my $prev = $FORMAT_NAME;
+ $FORMAT_NAME = qualify($_[1], caller) if @_ > 1;
$prev;
}
sub format_top_name {
- local($old) = select($_[0]);
- local($prev) = $FORMAT_TOP_NAME;
- $FORMAT_TOP_NAME = $_[1] if @_ > 1;
- select($old);
+ my $old = new SelectSaver qualify($_[0], caller);
+ my $prev = $FORMAT_TOP_NAME;
+ $FORMAT_TOP_NAME = qualify($_[1], caller) if @_ > 1;
$prev;
}
sub format_line_break_characters {
- local($old) = select($_[0]);
- local($prev) = $FORMAT_LINE_BREAK_CHARACTERS;
+ my $old = new SelectSaver qualify($_[0], caller);
+ my $prev = $FORMAT_LINE_BREAK_CHARACTERS;
$FORMAT_LINE_BREAK_CHARACTERS = $_[1] if @_ > 1;
- select($old);
$prev;
}
sub format_formfeed {
- local($old) = select($_[0]);
- local($prev) = $FORMAT_FORMFEED;
+ my $old = new SelectSaver qualify($_[0], caller);
+ my $prev = $FORMAT_FORMFEED;
$FORMAT_FORMFEED = $_[1] if @_ > 1;
- select($old);
$prev;
}
-
-# --- cacheout functions ---
-
-# Open in their package.
-
-sub cacheout_open {
- my $pack = caller(1);
- open(*{$pack . '::' . $_[0]}, $_[1]);
-}
-
-sub cacheout_close {
- my $pack = caller(1);
- close(*{$pack . '::' . $_[0]});
-}
-
-# But only this sub name is visible to them.
-
-sub cacheout {
- ($file) = @_;
- if (!$cacheout_maxopen){
- if (open(PARAM,'/usr/include/sys/param.h')) {
- local($.);
- while (<PARAM>) {
- $cacheout_maxopen = $1 - 4
- if /^\s*#\s*define\s+NOFILE\s+(\d+)/;
- }
- close PARAM;
- }
- $cacheout_maxopen = 16 unless $cacheout_maxopen;
- }
- if (!$isopen{$file}) {
- if (++$cacheout_numopen > $cacheout_maxopen) {
- local(@lru) = sort {$isopen{$a} <=> $isopen{$b};} keys(%isopen);
- splice(@lru, $cacheout_maxopen / 3);
- $cacheout_numopen -= @lru;
- for (@lru) { &cacheout_close($_); delete $isopen{$_}; }
- }
- &cacheout_open($file, ($saw{$file}++ ? '>>' : '>') . $file)
- || croak("Can't create $file: $!");
- }
- $isopen{$file} = ++$cacheout_seq;
-}
-
-$cacheout_seq = 0;
-$cacheout_numopen = 0;
-
1;