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package AnyEvent::Handle; |
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|
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no warnings; |
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use strict; |
5 |
|
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use AnyEvent (); |
7 |
use AnyEvent::Util qw(WSAEWOULDBLOCK); |
8 |
use Scalar::Util (); |
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use Carp (); |
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use Fcntl (); |
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use Errno qw(EAGAIN EINTR); |
12 |
|
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=head1 NAME |
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|
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AnyEvent::Handle - non-blocking I/O on file handles via AnyEvent |
16 |
|
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=cut |
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|
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our $VERSION = 4.1; |
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|
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=head1 SYNOPSIS |
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|
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use AnyEvent; |
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use AnyEvent::Handle; |
25 |
|
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my $cv = AnyEvent->condvar; |
27 |
|
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my $handle = |
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AnyEvent::Handle->new ( |
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fh => \*STDIN, |
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on_eof => sub { |
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$cv->broadcast; |
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}, |
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); |
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|
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# send some request line |
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$handle->push_write ("getinfo\015\012"); |
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|
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# read the response line |
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$handle->push_read (line => sub { |
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my ($handle, $line) = @_; |
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warn "read line <$line>\n"; |
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$cv->send; |
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}); |
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|
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$cv->recv; |
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|
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=head1 DESCRIPTION |
49 |
|
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This module is a helper module to make it easier to do event-based I/O on |
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filehandles. For utility functions for doing non-blocking connects and accepts |
52 |
on sockets see L<AnyEvent::Util>. |
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|
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In the following, when the documentation refers to of "bytes" then this |
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means characters. As sysread and syswrite are used for all I/O, their |
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treatment of characters applies to this module as well. |
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|
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All callbacks will be invoked with the handle object as their first |
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argument. |
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|
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=head1 METHODS |
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|
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=over 4 |
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|
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=item B<new (%args)> |
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|
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The constructor supports these arguments (all as key => value pairs). |
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|
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=over 4 |
70 |
|
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=item fh => $filehandle [MANDATORY] |
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|
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The filehandle this L<AnyEvent::Handle> object will operate on. |
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|
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NOTE: The filehandle will be set to non-blocking (using |
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AnyEvent::Util::fh_nonblocking). |
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|
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=item on_eof => $cb->($handle) |
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|
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Set the callback to be called when an end-of-file condition is detcted, |
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i.e. in the case of a socket, when the other side has closed the |
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connection cleanly. |
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|
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While not mandatory, it is highly recommended to set an eof callback, |
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otherwise you might end up with a closed socket while you are still |
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waiting for data. |
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|
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=item on_error => $cb->($handle, $fatal) |
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|
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This is the error callback, which is called when, well, some error |
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occured, such as not being able to resolve the hostname, failure to |
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connect or a read error. |
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|
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Some errors are fatal (which is indicated by C<$fatal> being true). On |
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fatal errors the handle object will be shut down and will not be |
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usable. Non-fatal errors can be retried by simply returning, but it is |
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recommended to simply ignore this parameter and instead abondon the handle |
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object when this callback is invoked. |
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|
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On callback entrance, the value of C<$!> contains the operating system |
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error (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT> or C<EBADMSG>). |
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|
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While not mandatory, it is I<highly> recommended to set this callback, as |
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you will not be notified of errors otherwise. The default simply calls |
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C<croak>. |
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|
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=item on_read => $cb->($handle) |
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|
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This sets the default read callback, which is called when data arrives |
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and no read request is in the queue. |
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|
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To access (and remove data from) the read buffer, use the C<< ->rbuf >> |
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method or access the C<$handle->{rbuf}> member directly. |
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|
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When an EOF condition is detected then AnyEvent::Handle will first try to |
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feed all the remaining data to the queued callbacks and C<on_read> before |
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calling the C<on_eof> callback. If no progress can be made, then a fatal |
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error will be raised (with C<$!> set to C<EPIPE>). |
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|
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=item on_drain => $cb->($handle) |
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|
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This sets the callback that is called when the write buffer becomes empty |
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(or when the callback is set and the buffer is empty already). |
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|
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To append to the write buffer, use the C<< ->push_write >> method. |
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|
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=item timeout => $fractional_seconds |
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|
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If non-zero, then this enables an "inactivity" timeout: whenever this many |
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seconds pass without a successful read or write on the underlying file |
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handle, the C<on_timeout> callback will be invoked (and if that one is |
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missing, an C<ETIMEDOUT> error will be raised). |
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|
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Note that timeout processing is also active when you currently do not have |
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any outstanding read or write requests: If you plan to keep the connection |
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idle then you should disable the timout temporarily or ignore the timeout |
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in the C<on_timeout> callback. |
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|
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Zero (the default) disables this timeout. |
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|
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=item on_timeout => $cb->($handle) |
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|
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Called whenever the inactivity timeout passes. If you return from this |
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callback, then the timeout will be reset as if some activity had happened, |
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so this condition is not fatal in any way. |
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|
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=item rbuf_max => <bytes> |
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|
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If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>) |
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when the read buffer ever (strictly) exceeds this size. This is useful to |
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avoid denial-of-service attacks. |
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|
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For example, a server accepting connections from untrusted sources should |
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be configured to accept only so-and-so much data that it cannot act on |
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(for example, when expecting a line, an attacker could send an unlimited |
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amount of data without a callback ever being called as long as the line |
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isn't finished). |
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|
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=item read_size => <bytes> |
160 |
|
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The default read block size (the amount of bytes this module will try to read |
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during each (loop iteration). Default: C<8192>. |
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|
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=item low_water_mark => <bytes> |
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|
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Sets the amount of bytes (default: C<0>) that make up an "empty" write |
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buffer: If the write reaches this size or gets even samller it is |
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considered empty. |
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|
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=item tls => "accept" | "connect" | Net::SSLeay::SSL object |
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|
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When this parameter is given, it enables TLS (SSL) mode, that means it |
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will start making tls handshake and will transparently encrypt/decrypt |
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data. |
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|
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TLS mode requires Net::SSLeay to be installed (it will be loaded |
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automatically when you try to create a TLS handle). |
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|
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For the TLS server side, use C<accept>, and for the TLS client side of a |
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connection, use C<connect> mode. |
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|
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You can also provide your own TLS connection object, but you have |
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to make sure that you call either C<Net::SSLeay::set_connect_state> |
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or C<Net::SSLeay::set_accept_state> on it before you pass it to |
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AnyEvent::Handle. |
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|
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See the C<starttls> method if you need to start TLs negotiation later. |
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|
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=item tls_ctx => $ssl_ctx |
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|
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Use the given Net::SSLeay::CTX object to create the new TLS connection |
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(unless a connection object was specified directly). If this parameter is |
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missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>. |
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|
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=item json => JSON or JSON::XS object |
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|
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This is the json coder object used by the C<json> read and write types. |
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|
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If you don't supply it, then AnyEvent::Handle will create and use a |
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suitable one, which will write and expect UTF-8 encoded JSON texts. |
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|
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Note that you are responsible to depend on the JSON module if you want to |
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use this functionality, as AnyEvent does not have a dependency itself. |
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|
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=item filter_r => $cb |
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|
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=item filter_w => $cb |
208 |
|
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These exist, but are undocumented at this time. |
210 |
|
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=back |
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|
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=cut |
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|
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sub new { |
216 |
my $class = shift; |
217 |
|
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my $self = bless { @_ }, $class; |
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|
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$self->{fh} or Carp::croak "mandatory argument fh is missing"; |
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|
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AnyEvent::Util::fh_nonblocking $self->{fh}, 1; |
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|
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if ($self->{tls}) { |
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require Net::SSLeay; |
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$self->starttls (delete $self->{tls}, delete $self->{tls_ctx}); |
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} |
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|
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# $self->on_eof (delete $self->{on_eof} ) if $self->{on_eof}; # nop |
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# $self->on_error (delete $self->{on_error}) if $self->{on_error}; # nop |
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# $self->on_read (delete $self->{on_read} ) if $self->{on_read}; # nop |
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$self->on_drain (delete $self->{on_drain}) if $self->{on_drain}; |
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|
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$self->{_activity} = AnyEvent->now; |
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$self->_timeout; |
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|
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$self->start_read; |
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|
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$self |
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} |
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|
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sub _shutdown { |
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my ($self) = @_; |
244 |
|
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delete $self->{_tw}; |
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delete $self->{_rw}; |
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delete $self->{_ww}; |
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delete $self->{fh}; |
249 |
|
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$self->stoptls; |
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} |
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|
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sub _error { |
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my ($self, $errno, $fatal) = @_; |
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|
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$self->_shutdown |
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if $fatal; |
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|
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$! = $errno; |
260 |
|
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if ($self->{on_error}) { |
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$self->{on_error}($self, $fatal); |
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} else { |
264 |
Carp::croak "AnyEvent::Handle uncaught error: $!"; |
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} |
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} |
267 |
|
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=item $fh = $handle->fh |
269 |
|
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This method returns the file handle of the L<AnyEvent::Handle> object. |
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|
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=cut |
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|
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sub fh { $_[0]{fh} } |
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|
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=item $handle->on_error ($cb) |
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|
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Replace the current C<on_error> callback (see the C<on_error> constructor argument). |
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|
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=cut |
281 |
|
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sub on_error { |
283 |
$_[0]{on_error} = $_[1]; |
284 |
} |
285 |
|
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=item $handle->on_eof ($cb) |
287 |
|
288 |
Replace the current C<on_eof> callback (see the C<on_eof> constructor argument). |
289 |
|
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=cut |
291 |
|
292 |
sub on_eof { |
293 |
$_[0]{on_eof} = $_[1]; |
294 |
} |
295 |
|
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=item $handle->on_timeout ($cb) |
297 |
|
298 |
Replace the current C<on_timeout> callback, or disables the callback |
299 |
(but not the timeout) if C<$cb> = C<undef>. See C<timeout> constructor |
300 |
argument. |
301 |
|
302 |
=cut |
303 |
|
304 |
sub on_timeout { |
305 |
$_[0]{on_timeout} = $_[1]; |
306 |
} |
307 |
|
308 |
############################################################################# |
309 |
|
310 |
=item $handle->timeout ($seconds) |
311 |
|
312 |
Configures (or disables) the inactivity timeout. |
313 |
|
314 |
=cut |
315 |
|
316 |
sub timeout { |
317 |
my ($self, $timeout) = @_; |
318 |
|
319 |
$self->{timeout} = $timeout; |
320 |
$self->_timeout; |
321 |
} |
322 |
|
323 |
# reset the timeout watcher, as neccessary |
324 |
# also check for time-outs |
325 |
sub _timeout { |
326 |
my ($self) = @_; |
327 |
|
328 |
if ($self->{timeout}) { |
329 |
my $NOW = AnyEvent->now; |
330 |
|
331 |
# when would the timeout trigger? |
332 |
my $after = $self->{_activity} + $self->{timeout} - $NOW; |
333 |
|
334 |
# now or in the past already? |
335 |
if ($after <= 0) { |
336 |
$self->{_activity} = $NOW; |
337 |
|
338 |
if ($self->{on_timeout}) { |
339 |
$self->{on_timeout}($self); |
340 |
} else { |
341 |
$self->_error (&Errno::ETIMEDOUT); |
342 |
} |
343 |
|
344 |
# callbakx could have changed timeout value, optimise |
345 |
return unless $self->{timeout}; |
346 |
|
347 |
# calculate new after |
348 |
$after = $self->{timeout}; |
349 |
} |
350 |
|
351 |
Scalar::Util::weaken $self; |
352 |
|
353 |
$self->{_tw} ||= AnyEvent->timer (after => $after, cb => sub { |
354 |
delete $self->{_tw}; |
355 |
$self->_timeout; |
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}); |
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} else { |
358 |
delete $self->{_tw}; |
359 |
} |
360 |
} |
361 |
|
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############################################################################# |
363 |
|
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=back |
365 |
|
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=head2 WRITE QUEUE |
367 |
|
368 |
AnyEvent::Handle manages two queues per handle, one for writing and one |
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for reading. |
370 |
|
371 |
The write queue is very simple: you can add data to its end, and |
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AnyEvent::Handle will automatically try to get rid of it for you. |
373 |
|
374 |
When data could be written and the write buffer is shorter then the low |
375 |
water mark, the C<on_drain> callback will be invoked. |
376 |
|
377 |
=over 4 |
378 |
|
379 |
=item $handle->on_drain ($cb) |
380 |
|
381 |
Sets the C<on_drain> callback or clears it (see the description of |
382 |
C<on_drain> in the constructor). |
383 |
|
384 |
=cut |
385 |
|
386 |
sub on_drain { |
387 |
my ($self, $cb) = @_; |
388 |
|
389 |
$self->{on_drain} = $cb; |
390 |
|
391 |
$cb->($self) |
392 |
if $cb && $self->{low_water_mark} >= length $self->{wbuf}; |
393 |
} |
394 |
|
395 |
=item $handle->push_write ($data) |
396 |
|
397 |
Queues the given scalar to be written. You can push as much data as you |
398 |
want (only limited by the available memory), as C<AnyEvent::Handle> |
399 |
buffers it independently of the kernel. |
400 |
|
401 |
=cut |
402 |
|
403 |
sub _drain_wbuf { |
404 |
my ($self) = @_; |
405 |
|
406 |
if (!$self->{_ww} && length $self->{wbuf}) { |
407 |
|
408 |
Scalar::Util::weaken $self; |
409 |
|
410 |
my $cb = sub { |
411 |
my $len = syswrite $self->{fh}, $self->{wbuf}; |
412 |
|
413 |
if ($len >= 0) { |
414 |
substr $self->{wbuf}, 0, $len, ""; |
415 |
|
416 |
$self->{_activity} = AnyEvent->now; |
417 |
|
418 |
$self->{on_drain}($self) |
419 |
if $self->{low_water_mark} >= length $self->{wbuf} |
420 |
&& $self->{on_drain}; |
421 |
|
422 |
delete $self->{_ww} unless length $self->{wbuf}; |
423 |
} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) { |
424 |
$self->_error ($!, 1); |
425 |
} |
426 |
}; |
427 |
|
428 |
# try to write data immediately |
429 |
$cb->(); |
430 |
|
431 |
# if still data left in wbuf, we need to poll |
432 |
$self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb) |
433 |
if length $self->{wbuf}; |
434 |
}; |
435 |
} |
436 |
|
437 |
our %WH; |
438 |
|
439 |
sub register_write_type($$) { |
440 |
$WH{$_[0]} = $_[1]; |
441 |
} |
442 |
|
443 |
sub push_write { |
444 |
my $self = shift; |
445 |
|
446 |
if (@_ > 1) { |
447 |
my $type = shift; |
448 |
|
449 |
@_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write") |
450 |
->($self, @_); |
451 |
} |
452 |
|
453 |
if ($self->{filter_w}) { |
454 |
$self->{filter_w}($self, \$_[0]); |
455 |
} else { |
456 |
$self->{wbuf} .= $_[0]; |
457 |
$self->_drain_wbuf; |
458 |
} |
459 |
} |
460 |
|
461 |
=item $handle->push_write (type => @args) |
462 |
|
463 |
Instead of formatting your data yourself, you can also let this module do |
464 |
the job by specifying a type and type-specific arguments. |
465 |
|
466 |
Predefined types are (if you have ideas for additional types, feel free to |
467 |
drop by and tell us): |
468 |
|
469 |
=over 4 |
470 |
|
471 |
=item netstring => $string |
472 |
|
473 |
Formats the given value as netstring |
474 |
(http://cr.yp.to/proto/netstrings.txt, this is not a recommendation to use them). |
475 |
|
476 |
=cut |
477 |
|
478 |
register_write_type netstring => sub { |
479 |
my ($self, $string) = @_; |
480 |
|
481 |
sprintf "%d:%s,", (length $string), $string |
482 |
}; |
483 |
|
484 |
=item json => $array_or_hashref |
485 |
|
486 |
Encodes the given hash or array reference into a JSON object. Unless you |
487 |
provide your own JSON object, this means it will be encoded to JSON text |
488 |
in UTF-8. |
489 |
|
490 |
JSON objects (and arrays) are self-delimiting, so you can write JSON at |
491 |
one end of a handle and read them at the other end without using any |
492 |
additional framing. |
493 |
|
494 |
The generated JSON text is guaranteed not to contain any newlines: While |
495 |
this module doesn't need delimiters after or between JSON texts to be |
496 |
able to read them, many other languages depend on that. |
497 |
|
498 |
A simple RPC protocol that interoperates easily with others is to send |
499 |
JSON arrays (or objects, although arrays are usually the better choice as |
500 |
they mimic how function argument passing works) and a newline after each |
501 |
JSON text: |
502 |
|
503 |
$handle->push_write (json => ["method", "arg1", "arg2"]); # whatever |
504 |
$handle->push_write ("\012"); |
505 |
|
506 |
An AnyEvent::Handle receiver would simply use the C<json> read type and |
507 |
rely on the fact that the newline will be skipped as leading whitespace: |
508 |
|
509 |
$handle->push_read (json => sub { my $array = $_[1]; ... }); |
510 |
|
511 |
Other languages could read single lines terminated by a newline and pass |
512 |
this line into their JSON decoder of choice. |
513 |
|
514 |
=cut |
515 |
|
516 |
register_write_type json => sub { |
517 |
my ($self, $ref) = @_; |
518 |
|
519 |
require JSON; |
520 |
|
521 |
$self->{json} ? $self->{json}->encode ($ref) |
522 |
: JSON::encode_json ($ref) |
523 |
}; |
524 |
|
525 |
=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args) |
526 |
|
527 |
This function (not method) lets you add your own types to C<push_write>. |
528 |
Whenever the given C<type> is used, C<push_write> will invoke the code |
529 |
reference with the handle object and the remaining arguments. |
530 |
|
531 |
The code reference is supposed to return a single octet string that will |
532 |
be appended to the write buffer. |
533 |
|
534 |
Note that this is a function, and all types registered this way will be |
535 |
global, so try to use unique names. |
536 |
|
537 |
=back |
538 |
|
539 |
=cut |
540 |
|
541 |
############################################################################# |
542 |
|
543 |
=back |
544 |
|
545 |
=head2 READ QUEUE |
546 |
|
547 |
AnyEvent::Handle manages two queues per handle, one for writing and one |
548 |
for reading. |
549 |
|
550 |
The read queue is more complex than the write queue. It can be used in two |
551 |
ways, the "simple" way, using only C<on_read> and the "complex" way, using |
552 |
a queue. |
553 |
|
554 |
In the simple case, you just install an C<on_read> callback and whenever |
555 |
new data arrives, it will be called. You can then remove some data (if |
556 |
enough is there) from the read buffer (C<< $handle->rbuf >>) if you want |
557 |
or not. |
558 |
|
559 |
In the more complex case, you want to queue multiple callbacks. In this |
560 |
case, AnyEvent::Handle will call the first queued callback each time new |
561 |
data arrives and removes it when it has done its job (see C<push_read>, |
562 |
below). |
563 |
|
564 |
This way you can, for example, push three line-reads, followed by reading |
565 |
a chunk of data, and AnyEvent::Handle will execute them in order. |
566 |
|
567 |
Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by |
568 |
the specified number of bytes which give an XML datagram. |
569 |
|
570 |
# in the default state, expect some header bytes |
571 |
$handle->on_read (sub { |
572 |
# some data is here, now queue the length-header-read (4 octets) |
573 |
shift->unshift_read (chunk => 4, sub { |
574 |
# header arrived, decode |
575 |
my $len = unpack "N", $_[1]; |
576 |
|
577 |
# now read the payload |
578 |
shift->unshift_read (chunk => $len, sub { |
579 |
my $xml = $_[1]; |
580 |
# handle xml |
581 |
}); |
582 |
}); |
583 |
}); |
584 |
|
585 |
Example 2: Implement a client for a protocol that replies either with |
586 |
"OK" and another line or "ERROR" for one request, and 64 bytes for the |
587 |
second request. Due tot he availability of a full queue, we can just |
588 |
pipeline sending both requests and manipulate the queue as necessary in |
589 |
the callbacks: |
590 |
|
591 |
# request one |
592 |
$handle->push_write ("request 1\015\012"); |
593 |
|
594 |
# we expect "ERROR" or "OK" as response, so push a line read |
595 |
$handle->push_read (line => sub { |
596 |
# if we got an "OK", we have to _prepend_ another line, |
597 |
# so it will be read before the second request reads its 64 bytes |
598 |
# which are already in the queue when this callback is called |
599 |
# we don't do this in case we got an error |
600 |
if ($_[1] eq "OK") { |
601 |
$_[0]->unshift_read (line => sub { |
602 |
my $response = $_[1]; |
603 |
... |
604 |
}); |
605 |
} |
606 |
}); |
607 |
|
608 |
# request two |
609 |
$handle->push_write ("request 2\015\012"); |
610 |
|
611 |
# simply read 64 bytes, always |
612 |
$handle->push_read (chunk => 64, sub { |
613 |
my $response = $_[1]; |
614 |
... |
615 |
}); |
616 |
|
617 |
=over 4 |
618 |
|
619 |
=cut |
620 |
|
621 |
sub _drain_rbuf { |
622 |
my ($self) = @_; |
623 |
|
624 |
if ( |
625 |
defined $self->{rbuf_max} |
626 |
&& $self->{rbuf_max} < length $self->{rbuf} |
627 |
) { |
628 |
return $self->_error (&Errno::ENOSPC, 1); |
629 |
} |
630 |
|
631 |
return if $self->{in_drain}; |
632 |
local $self->{in_drain} = 1; |
633 |
|
634 |
while (my $len = length $self->{rbuf}) { |
635 |
no strict 'refs'; |
636 |
if (my $cb = shift @{ $self->{_queue} }) { |
637 |
unless ($cb->($self)) { |
638 |
if ($self->{_eof}) { |
639 |
# no progress can be made (not enough data and no data forthcoming) |
640 |
return $self->_error (&Errno::EPIPE, 1); |
641 |
} |
642 |
|
643 |
unshift @{ $self->{_queue} }, $cb; |
644 |
return; |
645 |
} |
646 |
} elsif ($self->{on_read}) { |
647 |
$self->{on_read}($self); |
648 |
|
649 |
if ( |
650 |
$self->{_eof} # if no further data will arrive |
651 |
&& $len == length $self->{rbuf} # and no data has been consumed |
652 |
&& !@{ $self->{_queue} } # and the queue is still empty |
653 |
&& $self->{on_read} # and we still want to read data |
654 |
) { |
655 |
# then no progress can be made |
656 |
return $self->_error (&Errno::EPIPE, 1); |
657 |
} |
658 |
} else { |
659 |
# read side becomes idle |
660 |
delete $self->{_rw}; |
661 |
return; |
662 |
} |
663 |
} |
664 |
|
665 |
$self->{on_eof}($self) |
666 |
if $self->{_eof} && $self->{on_eof}; |
667 |
} |
668 |
|
669 |
=item $handle->on_read ($cb) |
670 |
|
671 |
This replaces the currently set C<on_read> callback, or clears it (when |
672 |
the new callback is C<undef>). See the description of C<on_read> in the |
673 |
constructor. |
674 |
|
675 |
=cut |
676 |
|
677 |
sub on_read { |
678 |
my ($self, $cb) = @_; |
679 |
|
680 |
$self->{on_read} = $cb; |
681 |
} |
682 |
|
683 |
=item $handle->rbuf |
684 |
|
685 |
Returns the read buffer (as a modifiable lvalue). |
686 |
|
687 |
You can access the read buffer directly as the C<< ->{rbuf} >> member, if |
688 |
you want. |
689 |
|
690 |
NOTE: The read buffer should only be used or modified if the C<on_read>, |
691 |
C<push_read> or C<unshift_read> methods are used. The other read methods |
692 |
automatically manage the read buffer. |
693 |
|
694 |
=cut |
695 |
|
696 |
sub rbuf : lvalue { |
697 |
$_[0]{rbuf} |
698 |
} |
699 |
|
700 |
=item $handle->push_read ($cb) |
701 |
|
702 |
=item $handle->unshift_read ($cb) |
703 |
|
704 |
Append the given callback to the end of the queue (C<push_read>) or |
705 |
prepend it (C<unshift_read>). |
706 |
|
707 |
The callback is called each time some additional read data arrives. |
708 |
|
709 |
It must check whether enough data is in the read buffer already. |
710 |
|
711 |
If not enough data is available, it must return the empty list or a false |
712 |
value, in which case it will be called repeatedly until enough data is |
713 |
available (or an error condition is detected). |
714 |
|
715 |
If enough data was available, then the callback must remove all data it is |
716 |
interested in (which can be none at all) and return a true value. After returning |
717 |
true, it will be removed from the queue. |
718 |
|
719 |
=cut |
720 |
|
721 |
our %RH; |
722 |
|
723 |
sub register_read_type($$) { |
724 |
$RH{$_[0]} = $_[1]; |
725 |
} |
726 |
|
727 |
sub push_read { |
728 |
my $self = shift; |
729 |
my $cb = pop; |
730 |
|
731 |
if (@_) { |
732 |
my $type = shift; |
733 |
|
734 |
$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read") |
735 |
->($self, $cb, @_); |
736 |
} |
737 |
|
738 |
push @{ $self->{_queue} }, $cb; |
739 |
$self->_drain_rbuf; |
740 |
} |
741 |
|
742 |
sub unshift_read { |
743 |
my $self = shift; |
744 |
my $cb = pop; |
745 |
|
746 |
if (@_) { |
747 |
my $type = shift; |
748 |
|
749 |
$cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::unshift_read") |
750 |
->($self, $cb, @_); |
751 |
} |
752 |
|
753 |
|
754 |
unshift @{ $self->{_queue} }, $cb; |
755 |
$self->_drain_rbuf; |
756 |
} |
757 |
|
758 |
=item $handle->push_read (type => @args, $cb) |
759 |
|
760 |
=item $handle->unshift_read (type => @args, $cb) |
761 |
|
762 |
Instead of providing a callback that parses the data itself you can chose |
763 |
between a number of predefined parsing formats, for chunks of data, lines |
764 |
etc. |
765 |
|
766 |
Predefined types are (if you have ideas for additional types, feel free to |
767 |
drop by and tell us): |
768 |
|
769 |
=over 4 |
770 |
|
771 |
=item chunk => $octets, $cb->($handle, $data) |
772 |
|
773 |
Invoke the callback only once C<$octets> bytes have been read. Pass the |
774 |
data read to the callback. The callback will never be called with less |
775 |
data. |
776 |
|
777 |
Example: read 2 bytes. |
778 |
|
779 |
$handle->push_read (chunk => 2, sub { |
780 |
warn "yay ", unpack "H*", $_[1]; |
781 |
}); |
782 |
|
783 |
=cut |
784 |
|
785 |
register_read_type chunk => sub { |
786 |
my ($self, $cb, $len) = @_; |
787 |
|
788 |
sub { |
789 |
$len <= length $_[0]{rbuf} or return; |
790 |
$cb->($_[0], substr $_[0]{rbuf}, 0, $len, ""); |
791 |
1 |
792 |
} |
793 |
}; |
794 |
|
795 |
# compatibility with older API |
796 |
sub push_read_chunk { |
797 |
$_[0]->push_read (chunk => $_[1], $_[2]); |
798 |
} |
799 |
|
800 |
sub unshift_read_chunk { |
801 |
$_[0]->unshift_read (chunk => $_[1], $_[2]); |
802 |
} |
803 |
|
804 |
=item line => [$eol, ]$cb->($handle, $line, $eol) |
805 |
|
806 |
The callback will be called only once a full line (including the end of |
807 |
line marker, C<$eol>) has been read. This line (excluding the end of line |
808 |
marker) will be passed to the callback as second argument (C<$line>), and |
809 |
the end of line marker as the third argument (C<$eol>). |
810 |
|
811 |
The end of line marker, C<$eol>, can be either a string, in which case it |
812 |
will be interpreted as a fixed record end marker, or it can be a regex |
813 |
object (e.g. created by C<qr>), in which case it is interpreted as a |
814 |
regular expression. |
815 |
|
816 |
The end of line marker argument C<$eol> is optional, if it is missing (NOT |
817 |
undef), then C<qr|\015?\012|> is used (which is good for most internet |
818 |
protocols). |
819 |
|
820 |
Partial lines at the end of the stream will never be returned, as they are |
821 |
not marked by the end of line marker. |
822 |
|
823 |
=cut |
824 |
|
825 |
register_read_type line => sub { |
826 |
my ($self, $cb, $eol) = @_; |
827 |
|
828 |
$eol = qr|(\015?\012)| if @_ < 3; |
829 |
$eol = quotemeta $eol unless ref $eol; |
830 |
$eol = qr|^(.*?)($eol)|s; |
831 |
|
832 |
sub { |
833 |
$_[0]{rbuf} =~ s/$eol// or return; |
834 |
|
835 |
$cb->($_[0], $1, $2); |
836 |
1 |
837 |
} |
838 |
}; |
839 |
|
840 |
# compatibility with older API |
841 |
sub push_read_line { |
842 |
my $self = shift; |
843 |
$self->push_read (line => @_); |
844 |
} |
845 |
|
846 |
sub unshift_read_line { |
847 |
my $self = shift; |
848 |
$self->unshift_read (line => @_); |
849 |
} |
850 |
|
851 |
=item netstring => $cb->($handle, $string) |
852 |
|
853 |
A netstring (http://cr.yp.to/proto/netstrings.txt, this is not an endorsement). |
854 |
|
855 |
Throws an error with C<$!> set to EBADMSG on format violations. |
856 |
|
857 |
=cut |
858 |
|
859 |
register_read_type netstring => sub { |
860 |
my ($self, $cb) = @_; |
861 |
|
862 |
sub { |
863 |
unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) { |
864 |
if ($_[0]{rbuf} =~ /[^0-9]/) { |
865 |
$self->_error (&Errno::EBADMSG); |
866 |
} |
867 |
return; |
868 |
} |
869 |
|
870 |
my $len = $1; |
871 |
|
872 |
$self->unshift_read (chunk => $len, sub { |
873 |
my $string = $_[1]; |
874 |
$_[0]->unshift_read (chunk => 1, sub { |
875 |
if ($_[1] eq ",") { |
876 |
$cb->($_[0], $string); |
877 |
} else { |
878 |
$self->_error (&Errno::EBADMSG); |
879 |
} |
880 |
}); |
881 |
}); |
882 |
|
883 |
1 |
884 |
} |
885 |
}; |
886 |
|
887 |
=item regex => $accept[, $reject[, $skip], $cb->($handle, $data) |
888 |
|
889 |
Makes a regex match against the regex object C<$accept> and returns |
890 |
everything up to and including the match. |
891 |
|
892 |
Example: read a single line terminated by '\n'. |
893 |
|
894 |
$handle->push_read (regex => qr<\n>, sub { ... }); |
895 |
|
896 |
If C<$reject> is given and not undef, then it determines when the data is |
897 |
to be rejected: it is matched against the data when the C<$accept> regex |
898 |
does not match and generates an C<EBADMSG> error when it matches. This is |
899 |
useful to quickly reject wrong data (to avoid waiting for a timeout or a |
900 |
receive buffer overflow). |
901 |
|
902 |
Example: expect a single decimal number followed by whitespace, reject |
903 |
anything else (not the use of an anchor). |
904 |
|
905 |
$handle->push_read (regex => qr<^[0-9]+\s>, qr<[^0-9]>, sub { ... }); |
906 |
|
907 |
If C<$skip> is given and not C<undef>, then it will be matched against |
908 |
the receive buffer when neither C<$accept> nor C<$reject> match, |
909 |
and everything preceding and including the match will be accepted |
910 |
unconditionally. This is useful to skip large amounts of data that you |
911 |
know cannot be matched, so that the C<$accept> or C<$reject> regex do not |
912 |
have to start matching from the beginning. This is purely an optimisation |
913 |
and is usually worth only when you expect more than a few kilobytes. |
914 |
|
915 |
Example: expect a http header, which ends at C<\015\012\015\012>. Since we |
916 |
expect the header to be very large (it isn't in practise, but...), we use |
917 |
a skip regex to skip initial portions. The skip regex is tricky in that |
918 |
it only accepts something not ending in either \015 or \012, as these are |
919 |
required for the accept regex. |
920 |
|
921 |
$handle->push_read (regex => |
922 |
qr<\015\012\015\012>, |
923 |
undef, # no reject |
924 |
qr<^.*[^\015\012]>, |
925 |
sub { ... }); |
926 |
|
927 |
=cut |
928 |
|
929 |
register_read_type regex => sub { |
930 |
my ($self, $cb, $accept, $reject, $skip) = @_; |
931 |
|
932 |
my $data; |
933 |
my $rbuf = \$self->{rbuf}; |
934 |
|
935 |
sub { |
936 |
# accept |
937 |
if ($$rbuf =~ $accept) { |
938 |
$data .= substr $$rbuf, 0, $+[0], ""; |
939 |
$cb->($self, $data); |
940 |
return 1; |
941 |
} |
942 |
|
943 |
# reject |
944 |
if ($reject && $$rbuf =~ $reject) { |
945 |
$self->_error (&Errno::EBADMSG); |
946 |
} |
947 |
|
948 |
# skip |
949 |
if ($skip && $$rbuf =~ $skip) { |
950 |
$data .= substr $$rbuf, 0, $+[0], ""; |
951 |
} |
952 |
|
953 |
() |
954 |
} |
955 |
}; |
956 |
|
957 |
=item json => $cb->($handle, $hash_or_arrayref) |
958 |
|
959 |
Reads a JSON object or array, decodes it and passes it to the callback. |
960 |
|
961 |
If a C<json> object was passed to the constructor, then that will be used |
962 |
for the final decode, otherwise it will create a JSON coder expecting UTF-8. |
963 |
|
964 |
This read type uses the incremental parser available with JSON version |
965 |
2.09 (and JSON::XS version 2.2) and above. You have to provide a |
966 |
dependency on your own: this module will load the JSON module, but |
967 |
AnyEvent does not depend on it itself. |
968 |
|
969 |
Since JSON texts are fully self-delimiting, the C<json> read and write |
970 |
types are an ideal simple RPC protocol: just exchange JSON datagrams. See |
971 |
the C<json> write type description, above, for an actual example. |
972 |
|
973 |
=cut |
974 |
|
975 |
register_read_type json => sub { |
976 |
my ($self, $cb, $accept, $reject, $skip) = @_; |
977 |
|
978 |
require JSON; |
979 |
|
980 |
my $data; |
981 |
my $rbuf = \$self->{rbuf}; |
982 |
|
983 |
my $json = $self->{json} ||= JSON->new->utf8; |
984 |
|
985 |
sub { |
986 |
my $ref = $json->incr_parse ($self->{rbuf}); |
987 |
|
988 |
if ($ref) { |
989 |
$self->{rbuf} = $json->incr_text; |
990 |
$json->incr_text = ""; |
991 |
$cb->($self, $ref); |
992 |
|
993 |
1 |
994 |
} else { |
995 |
$self->{rbuf} = ""; |
996 |
() |
997 |
} |
998 |
} |
999 |
}; |
1000 |
|
1001 |
=back |
1002 |
|
1003 |
=item AnyEvent::Handle::register_read_type type => $coderef->($handle, $cb, @args) |
1004 |
|
1005 |
This function (not method) lets you add your own types to C<push_read>. |
1006 |
|
1007 |
Whenever the given C<type> is used, C<push_read> will invoke the code |
1008 |
reference with the handle object, the callback and the remaining |
1009 |
arguments. |
1010 |
|
1011 |
The code reference is supposed to return a callback (usually a closure) |
1012 |
that works as a plain read callback (see C<< ->push_read ($cb) >>). |
1013 |
|
1014 |
It should invoke the passed callback when it is done reading (remember to |
1015 |
pass C<$handle> as first argument as all other callbacks do that). |
1016 |
|
1017 |
Note that this is a function, and all types registered this way will be |
1018 |
global, so try to use unique names. |
1019 |
|
1020 |
For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>, |
1021 |
search for C<register_read_type>)). |
1022 |
|
1023 |
=item $handle->stop_read |
1024 |
|
1025 |
=item $handle->start_read |
1026 |
|
1027 |
In rare cases you actually do not want to read anything from the |
1028 |
socket. In this case you can call C<stop_read>. Neither C<on_read> no |
1029 |
any queued callbacks will be executed then. To start reading again, call |
1030 |
C<start_read>. |
1031 |
|
1032 |
=cut |
1033 |
|
1034 |
sub stop_read { |
1035 |
my ($self) = @_; |
1036 |
|
1037 |
delete $self->{_rw}; |
1038 |
} |
1039 |
|
1040 |
sub start_read { |
1041 |
my ($self) = @_; |
1042 |
|
1043 |
unless ($self->{_rw} || $self->{_eof}) { |
1044 |
Scalar::Util::weaken $self; |
1045 |
|
1046 |
$self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub { |
1047 |
my $rbuf = $self->{filter_r} ? \my $buf : \$self->{rbuf}; |
1048 |
my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf; |
1049 |
|
1050 |
if ($len > 0) { |
1051 |
$self->{_activity} = AnyEvent->now; |
1052 |
|
1053 |
$self->{filter_r} |
1054 |
? $self->{filter_r}($self, $rbuf) |
1055 |
: $self->_drain_rbuf; |
1056 |
|
1057 |
} elsif (defined $len) { |
1058 |
delete $self->{_rw}; |
1059 |
$self->{_eof} = 1; |
1060 |
$self->_drain_rbuf; |
1061 |
|
1062 |
} elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) { |
1063 |
return $self->_error ($!, 1); |
1064 |
} |
1065 |
}); |
1066 |
} |
1067 |
} |
1068 |
|
1069 |
sub _dotls { |
1070 |
my ($self) = @_; |
1071 |
|
1072 |
if (length $self->{_tls_wbuf}) { |
1073 |
while ((my $len = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) { |
1074 |
substr $self->{_tls_wbuf}, 0, $len, ""; |
1075 |
} |
1076 |
} |
1077 |
|
1078 |
if (defined (my $buf = Net::SSLeay::BIO_read ($self->{_wbio}))) { |
1079 |
$self->{wbuf} .= $buf; |
1080 |
$self->_drain_wbuf; |
1081 |
} |
1082 |
|
1083 |
while (defined (my $buf = Net::SSLeay::read ($self->{tls}))) { |
1084 |
$self->{rbuf} .= $buf; |
1085 |
$self->_drain_rbuf; |
1086 |
} |
1087 |
|
1088 |
my $err = Net::SSLeay::get_error ($self->{tls}, -1); |
1089 |
|
1090 |
if ($err!= Net::SSLeay::ERROR_WANT_READ ()) { |
1091 |
if ($err == Net::SSLeay::ERROR_SYSCALL ()) { |
1092 |
return $self->_error ($!, 1); |
1093 |
} elsif ($err == Net::SSLeay::ERROR_SSL ()) { |
1094 |
return $self->_error (&Errno::EIO, 1); |
1095 |
} |
1096 |
|
1097 |
# all others are fine for our purposes |
1098 |
} |
1099 |
} |
1100 |
|
1101 |
=item $handle->starttls ($tls[, $tls_ctx]) |
1102 |
|
1103 |
Instead of starting TLS negotiation immediately when the AnyEvent::Handle |
1104 |
object is created, you can also do that at a later time by calling |
1105 |
C<starttls>. |
1106 |
|
1107 |
The first argument is the same as the C<tls> constructor argument (either |
1108 |
C<"connect">, C<"accept"> or an existing Net::SSLeay object). |
1109 |
|
1110 |
The second argument is the optional C<Net::SSLeay::CTX> object that is |
1111 |
used when AnyEvent::Handle has to create its own TLS connection object. |
1112 |
|
1113 |
The TLS connection object will end up in C<< $handle->{tls} >> after this |
1114 |
call and can be used or changed to your liking. Note that the handshake |
1115 |
might have already started when this function returns. |
1116 |
|
1117 |
=cut |
1118 |
|
1119 |
sub starttls { |
1120 |
my ($self, $ssl, $ctx) = @_; |
1121 |
|
1122 |
$self->stoptls; |
1123 |
|
1124 |
if ($ssl eq "accept") { |
1125 |
$ssl = Net::SSLeay::new ($ctx || TLS_CTX ()); |
1126 |
Net::SSLeay::set_accept_state ($ssl); |
1127 |
} elsif ($ssl eq "connect") { |
1128 |
$ssl = Net::SSLeay::new ($ctx || TLS_CTX ()); |
1129 |
Net::SSLeay::set_connect_state ($ssl); |
1130 |
} |
1131 |
|
1132 |
$self->{tls} = $ssl; |
1133 |
|
1134 |
# basically, this is deep magic (because SSL_read should have the same issues) |
1135 |
# but the openssl maintainers basically said: "trust us, it just works". |
1136 |
# (unfortunately, we have to hardcode constants because the abysmally misdesigned |
1137 |
# and mismaintained ssleay-module doesn't even offer them). |
1138 |
# http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html |
1139 |
Net::SSLeay::CTX_set_mode ($self->{tls}, |
1140 |
(eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1) |
1141 |
| (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2)); |
1142 |
|
1143 |
$self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); |
1144 |
$self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); |
1145 |
|
1146 |
Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio}); |
1147 |
|
1148 |
$self->{filter_w} = sub { |
1149 |
$_[0]{_tls_wbuf} .= ${$_[1]}; |
1150 |
&_dotls; |
1151 |
}; |
1152 |
$self->{filter_r} = sub { |
1153 |
Net::SSLeay::BIO_write ($_[0]{_rbio}, ${$_[1]}); |
1154 |
&_dotls; |
1155 |
}; |
1156 |
} |
1157 |
|
1158 |
=item $handle->stoptls |
1159 |
|
1160 |
Destroys the SSL connection, if any. Partial read or write data will be |
1161 |
lost. |
1162 |
|
1163 |
=cut |
1164 |
|
1165 |
sub stoptls { |
1166 |
my ($self) = @_; |
1167 |
|
1168 |
Net::SSLeay::free (delete $self->{tls}) if $self->{tls}; |
1169 |
|
1170 |
delete $self->{_rbio}; |
1171 |
delete $self->{_wbio}; |
1172 |
delete $self->{_tls_wbuf}; |
1173 |
delete $self->{filter_r}; |
1174 |
delete $self->{filter_w}; |
1175 |
} |
1176 |
|
1177 |
sub DESTROY { |
1178 |
my $self = shift; |
1179 |
|
1180 |
$self->stoptls; |
1181 |
} |
1182 |
|
1183 |
=item AnyEvent::Handle::TLS_CTX |
1184 |
|
1185 |
This function creates and returns the Net::SSLeay::CTX object used by |
1186 |
default for TLS mode. |
1187 |
|
1188 |
The context is created like this: |
1189 |
|
1190 |
Net::SSLeay::load_error_strings; |
1191 |
Net::SSLeay::SSLeay_add_ssl_algorithms; |
1192 |
Net::SSLeay::randomize; |
1193 |
|
1194 |
my $CTX = Net::SSLeay::CTX_new; |
1195 |
|
1196 |
Net::SSLeay::CTX_set_options $CTX, Net::SSLeay::OP_ALL |
1197 |
|
1198 |
=cut |
1199 |
|
1200 |
our $TLS_CTX; |
1201 |
|
1202 |
sub TLS_CTX() { |
1203 |
$TLS_CTX || do { |
1204 |
require Net::SSLeay; |
1205 |
|
1206 |
Net::SSLeay::load_error_strings (); |
1207 |
Net::SSLeay::SSLeay_add_ssl_algorithms (); |
1208 |
Net::SSLeay::randomize (); |
1209 |
|
1210 |
$TLS_CTX = Net::SSLeay::CTX_new (); |
1211 |
|
1212 |
Net::SSLeay::CTX_set_options ($TLS_CTX, Net::SSLeay::OP_ALL ()); |
1213 |
|
1214 |
$TLS_CTX |
1215 |
} |
1216 |
} |
1217 |
|
1218 |
=back |
1219 |
|
1220 |
=head1 SUBCLASSING AnyEvent::Handle |
1221 |
|
1222 |
In many cases, you might want to subclass AnyEvent::Handle. |
1223 |
|
1224 |
To make this easier, a given version of AnyEvent::Handle uses these |
1225 |
conventions: |
1226 |
|
1227 |
=over 4 |
1228 |
|
1229 |
=item * all constructor arguments become object members. |
1230 |
|
1231 |
At least initially, when you pass a C<tls>-argument to the constructor it |
1232 |
will end up in C<< $handle->{tls} >>. Those members might be changes or |
1233 |
mutated later on (for example C<tls> will hold the TLS connection object). |
1234 |
|
1235 |
=item * other object member names are prefixed with an C<_>. |
1236 |
|
1237 |
All object members not explicitly documented (internal use) are prefixed |
1238 |
with an underscore character, so the remaining non-C<_>-namespace is free |
1239 |
for use for subclasses. |
1240 |
|
1241 |
=item * all members not documented here and not prefixed with an underscore |
1242 |
are free to use in subclasses. |
1243 |
|
1244 |
Of course, new versions of AnyEvent::Handle may introduce more "public" |
1245 |
member variables, but thats just life, at least it is documented. |
1246 |
|
1247 |
=back |
1248 |
|
1249 |
=head1 AUTHOR |
1250 |
|
1251 |
Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>. |
1252 |
|
1253 |
=cut |
1254 |
|
1255 |
1; # End of AnyEvent::Handle |