| 1 |
=head1 NAME |
| 2 |
|
| 3 |
Coro::Handle - non-blocking io with a blocking interface. |
| 4 |
|
| 5 |
=head1 SYNOPSIS |
| 6 |
|
| 7 |
use Coro::Handle; |
| 8 |
|
| 9 |
=head1 DESCRIPTION |
| 10 |
|
| 11 |
This module implements io-handles in a coroutine-compatible way, that is, |
| 12 |
other coroutines can run while reads or writes block on the handle. It |
| 13 |
does NOT inherit from IO::Handle but uses tied objects. |
| 14 |
|
| 15 |
=over 4 |
| 16 |
|
| 17 |
=cut |
| 18 |
|
| 19 |
package Coro::Handle; |
| 20 |
|
| 21 |
use Errno (); |
| 22 |
use base 'Exporter'; |
| 23 |
|
| 24 |
$VERSION = 0.13; |
| 25 |
|
| 26 |
@EXPORT = qw(unblock); |
| 27 |
|
| 28 |
=item $fh = new_from_fh Coro::Handle $fhandle [, arg => value...] |
| 29 |
|
| 30 |
Create a new non-blocking io-handle using the given |
| 31 |
perl-filehandle. Returns undef if no fhandle is given. The only other |
| 32 |
supported argument is "timeout", which sets a timeout for each operation. |
| 33 |
|
| 34 |
=cut |
| 35 |
|
| 36 |
sub new_from_fh { |
| 37 |
my $class = shift; |
| 38 |
my $fh = shift or return; |
| 39 |
my $self = do { local *Coro::Handle }; |
| 40 |
|
| 41 |
my ($package, $filename, $line) = caller; |
| 42 |
$filename =~ s/^.*[\/\\]//; |
| 43 |
|
| 44 |
tie $self, Coro::Handle::FH, fh => $fh, desc => "$filename:$line", @_; |
| 45 |
|
| 46 |
my $_fh = select bless \$self, $class; $| = 1; select $_fh; |
| 47 |
} |
| 48 |
|
| 49 |
=item $fh = unblock $fh |
| 50 |
|
| 51 |
This is a convinience function that just calls C<new_from_fh> on the given |
| 52 |
filehandle. Use it to replace a normal perl filehandle by a non-blocking |
| 53 |
equivalent. |
| 54 |
|
| 55 |
=cut |
| 56 |
|
| 57 |
sub unblock($) { |
| 58 |
new_from_fh Coro::Handle $_[0]; |
| 59 |
} |
| 60 |
|
| 61 |
sub read { read $_[0], $_[1], $_[2], $_[3] } |
| 62 |
sub sysread { sysread $_[0], $_[1], $_[2], $_[3] } |
| 63 |
sub syswrite { syswrite $_[0], $_[1], $_[2], $_[3] } |
| 64 |
|
| 65 |
=item $fh->writable, $fh->readable |
| 66 |
|
| 67 |
Wait until the filehandle is readable or writable (and return true) or |
| 68 |
until an error condition happens (and return false). |
| 69 |
|
| 70 |
=cut |
| 71 |
|
| 72 |
sub readable { tied(${$_[0]})->readable } |
| 73 |
sub writable { tied(${$_[0]})->writable } |
| 74 |
|
| 75 |
=item $fh->readline([$terminator]) |
| 76 |
|
| 77 |
Like the builtin of the same name, but allows you to specify the input |
| 78 |
record separator in a coroutine-safe manner (i.e. not using a global |
| 79 |
variable). |
| 80 |
|
| 81 |
=cut |
| 82 |
|
| 83 |
sub readline { tied(${+shift})->READLINE(@_) } |
| 84 |
|
| 85 |
=item $fh->autoflush([...]) |
| 86 |
|
| 87 |
Always returns true, arguments are being ignored (exists for compatibility |
| 88 |
only). Might change in the future. |
| 89 |
|
| 90 |
=cut |
| 91 |
|
| 92 |
sub autoflush { !0 } |
| 93 |
|
| 94 |
=item $fh->fileno |
| 95 |
|
| 96 |
Returns the file number of the handle. |
| 97 |
|
| 98 |
=cut |
| 99 |
|
| 100 |
sub fileno { |
| 101 |
tied(${+shift})->FILENO; |
| 102 |
} |
| 103 |
|
| 104 |
=item $fh->timeout([...]) |
| 105 |
|
| 106 |
The optional agrument sets the new timeout (in seconds) for this |
| 107 |
handle. Returns the current (new) value. |
| 108 |
|
| 109 |
C<0> is a valid timeout, use C<undef> to disable the timeout. |
| 110 |
|
| 111 |
=cut |
| 112 |
|
| 113 |
sub timeout { |
| 114 |
my $self = tied(${+shift}); |
| 115 |
if (@_) { |
| 116 |
$self->{timeout} = $_[0]; |
| 117 |
$self->{rw}->timeout($_[0]) if $self->{rw}; |
| 118 |
$self->{ww}->timeout($_[0]) if $self->{ww}; |
| 119 |
} |
| 120 |
$self->{timeout}; |
| 121 |
} |
| 122 |
|
| 123 |
package Coro::Handle::FH; |
| 124 |
|
| 125 |
use Fcntl (); |
| 126 |
use Errno (); |
| 127 |
|
| 128 |
use Coro::Event; |
| 129 |
use Event::Watcher qw(R W E); |
| 130 |
|
| 131 |
use base 'Tie::Handle'; |
| 132 |
|
| 133 |
sub TIEHANDLE { |
| 134 |
my $class = shift; |
| 135 |
|
| 136 |
my $self = bless { |
| 137 |
rb => "", |
| 138 |
wb => "", |
| 139 |
@_, |
| 140 |
}, $class; |
| 141 |
|
| 142 |
fcntl $self->{fh}, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK |
| 143 |
or die "fcntl(O_NONBLOCK): $!"; |
| 144 |
|
| 145 |
$self; |
| 146 |
} |
| 147 |
|
| 148 |
sub OPEN { |
| 149 |
my $self = shift; |
| 150 |
$self->CLOSE; |
| 151 |
my $r = @_ == 2 ? open $self->{fh}, $_[0], $_[1] |
| 152 |
: open $self->{fh}, $_[0], $_[1], $_[2]; |
| 153 |
if ($r) { |
| 154 |
fcntl $self->{fh}, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK |
| 155 |
or die "fcntl(O_NONBLOCK): $!"; |
| 156 |
} |
| 157 |
$r; |
| 158 |
} |
| 159 |
|
| 160 |
sub CLOSE { |
| 161 |
my $self = shift; |
| 162 |
$self->{rb} = |
| 163 |
$self->{wb} = ""; |
| 164 |
(delete $self->{rw})->cancel if $self->{rw}; |
| 165 |
(delete $self->{ww})->cancel if $self->{ww}; |
| 166 |
close $self->{fh}; |
| 167 |
} |
| 168 |
|
| 169 |
sub FILENO { |
| 170 |
fileno $_[0]->{fh}; |
| 171 |
} |
| 172 |
|
| 173 |
sub writable { |
| 174 |
($_[0]->{ww} ||= Coro::Event->io( |
| 175 |
fd => $_[0]->{fh}, |
| 176 |
desc => "$_[0]->{desc} WW", |
| 177 |
timeout => $_[0]->{timeout}, |
| 178 |
poll => W+E, |
| 179 |
))->next->got & W; |
| 180 |
} |
| 181 |
|
| 182 |
sub readable { |
| 183 |
($_[0]->{rw} ||= Coro::Event->io( |
| 184 |
fd => $_[0]->{fh}, |
| 185 |
desc => "$_[0]->{desc} RW", |
| 186 |
timeout => $_[0]->{timeout}, |
| 187 |
poll => R+E, |
| 188 |
))->next->got & R; |
| 189 |
} |
| 190 |
|
| 191 |
sub WRITE { |
| 192 |
my $self = $_[0]; |
| 193 |
my $len = defined $_[2] ? $_[2] : length $_[1]; |
| 194 |
my $ofs = $_[3]; |
| 195 |
my $res = 0; |
| 196 |
|
| 197 |
while() { |
| 198 |
my $r = syswrite $self->{fh}, $_[1], $len, $ofs; |
| 199 |
if (defined $r) { |
| 200 |
$len -= $r; |
| 201 |
$ofs += $r; |
| 202 |
$res += $r; |
| 203 |
last unless $len; |
| 204 |
} elsif ($! != Errno::EAGAIN) { |
| 205 |
last; |
| 206 |
} |
| 207 |
last unless $self->writable; |
| 208 |
} |
| 209 |
|
| 210 |
return $res; |
| 211 |
} |
| 212 |
|
| 213 |
sub READ { |
| 214 |
my $self = $_[0]; |
| 215 |
my $len = $_[2]; |
| 216 |
my $ofs = $_[3]; |
| 217 |
my $res = 0; |
| 218 |
|
| 219 |
# first deplete the read buffer |
| 220 |
if (exists $self->{rb}) { |
| 221 |
my $l = length $self->{rb}; |
| 222 |
if ($l <= $len) { |
| 223 |
substr($_[1], $ofs) = delete $self->{rb}; |
| 224 |
$len -= $l; |
| 225 |
$res += $l; |
| 226 |
return $res unless $len; |
| 227 |
} else { |
| 228 |
substr($_[1], $ofs) = substr($self->{rb}, 0, $len); |
| 229 |
substr($self->{rb}, 0, $len) = ""; |
| 230 |
return $len; |
| 231 |
} |
| 232 |
} |
| 233 |
|
| 234 |
while() { |
| 235 |
my $r = sysread $self->{fh}, $_[1], $len, $ofs; |
| 236 |
if (defined $r) { |
| 237 |
$len -= $r; |
| 238 |
$ofs += $r; |
| 239 |
$res += $r; |
| 240 |
last unless $len && $r; |
| 241 |
} elsif ($! != Errno::EAGAIN) { |
| 242 |
last; |
| 243 |
} |
| 244 |
last unless $self->readable; |
| 245 |
} |
| 246 |
|
| 247 |
return $res; |
| 248 |
} |
| 249 |
|
| 250 |
sub READLINE { |
| 251 |
my $self = shift; |
| 252 |
my $irs = @_ ? shift : $/; |
| 253 |
|
| 254 |
while() { |
| 255 |
my $pos = index $self->{rb}, $irs; |
| 256 |
if ($pos >= 0) { |
| 257 |
$pos += length $irs; |
| 258 |
my $res = substr $self->{rb}, 0, $pos; |
| 259 |
substr ($self->{rb}, 0, $pos) = ""; |
| 260 |
return $res; |
| 261 |
} |
| 262 |
my $r = sysread $self->{fh}, $self->{rb}, 8192, length $self->{rb}; |
| 263 |
if (defined $r) { |
| 264 |
return undef unless $r; |
| 265 |
} elsif ($! != Errno::EAGAIN || !$self->readable) { |
| 266 |
return undef; |
| 267 |
} |
| 268 |
} |
| 269 |
} |
| 270 |
|
| 271 |
sub DESTROY { |
| 272 |
&CLOSE; |
| 273 |
} |
| 274 |
|
| 275 |
1; |
| 276 |
|
| 277 |
=head1 BUGS |
| 278 |
|
| 279 |
- Perl's IO-Handle model is THE bug. |
| 280 |
|
| 281 |
=head1 AUTHOR |
| 282 |
|
| 283 |
Marc Lehmann <pcg@goof.com> |
| 284 |
http://www.goof.com/pcg/marc/ |
| 285 |
|
| 286 |
=cut |
| 287 |
|
