1 | package AnyEvent::Handle; |
1 | package AnyEvent::Handle; |
2 | |
2 | |
3 | no warnings; |
3 | no warnings; |
4 | use strict; |
4 | use strict qw(subs vars); |
5 | |
5 | |
6 | use AnyEvent (); |
6 | use AnyEvent (); |
7 | use AnyEvent::Util qw(WSAEWOULDBLOCK); |
7 | use AnyEvent::Util qw(WSAEWOULDBLOCK); |
8 | use Scalar::Util (); |
8 | use Scalar::Util (); |
9 | use Carp (); |
9 | use Carp (); |
… | |
… | |
14 | |
14 | |
15 | AnyEvent::Handle - non-blocking I/O on file handles via AnyEvent |
15 | AnyEvent::Handle - non-blocking I/O on file handles via AnyEvent |
16 | |
16 | |
17 | =cut |
17 | =cut |
18 | |
18 | |
19 | our $VERSION = 4.22; |
19 | our $VERSION = 4.232; |
20 | |
20 | |
21 | =head1 SYNOPSIS |
21 | =head1 SYNOPSIS |
22 | |
22 | |
23 | use AnyEvent; |
23 | use AnyEvent; |
24 | use AnyEvent::Handle; |
24 | use AnyEvent::Handle; |
… | |
… | |
49 | |
49 | |
50 | This module is a helper module to make it easier to do event-based I/O on |
50 | This module is a helper module to make it easier to do event-based I/O on |
51 | filehandles. For utility functions for doing non-blocking connects and accepts |
51 | filehandles. For utility functions for doing non-blocking connects and accepts |
52 | on sockets see L<AnyEvent::Util>. |
52 | on sockets see L<AnyEvent::Util>. |
53 | |
53 | |
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54 | The L<AnyEvent::Intro> tutorial contains some well-documented |
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55 | AnyEvent::Handle examples. |
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56 | |
54 | In the following, when the documentation refers to of "bytes" then this |
57 | In the following, when the documentation refers to of "bytes" then this |
55 | means characters. As sysread and syswrite are used for all I/O, their |
58 | means characters. As sysread and syswrite are used for all I/O, their |
56 | treatment of characters applies to this module as well. |
59 | treatment of characters applies to this module as well. |
57 | |
60 | |
58 | All callbacks will be invoked with the handle object as their first |
61 | All callbacks will be invoked with the handle object as their first |
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… | |
70 | |
73 | |
71 | =item fh => $filehandle [MANDATORY] |
74 | =item fh => $filehandle [MANDATORY] |
72 | |
75 | |
73 | The filehandle this L<AnyEvent::Handle> object will operate on. |
76 | The filehandle this L<AnyEvent::Handle> object will operate on. |
74 | |
77 | |
75 | NOTE: The filehandle will be set to non-blocking (using |
78 | NOTE: The filehandle will be set to non-blocking mode (using |
76 | AnyEvent::Util::fh_nonblocking). |
79 | C<AnyEvent::Util::fh_nonblocking>) by the constructor and needs to stay in |
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80 | that mode. |
77 | |
81 | |
78 | =item on_eof => $cb->($handle) |
82 | =item on_eof => $cb->($handle) |
79 | |
83 | |
80 | Set the callback to be called when an end-of-file condition is detcted, |
84 | Set the callback to be called when an end-of-file condition is detected, |
81 | i.e. in the case of a socket, when the other side has closed the |
85 | i.e. in the case of a socket, when the other side has closed the |
82 | connection cleanly. |
86 | connection cleanly. |
83 | |
87 | |
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88 | For sockets, this just means that the other side has stopped sending data, |
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89 | you can still try to write data, and, in fact, one can return from the eof |
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90 | callback and continue writing data, as only the read part has been shut |
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91 | down. |
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92 | |
84 | While not mandatory, it is highly recommended to set an eof callback, |
93 | While not mandatory, it is I<highly> recommended to set an eof callback, |
85 | otherwise you might end up with a closed socket while you are still |
94 | otherwise you might end up with a closed socket while you are still |
86 | waiting for data. |
95 | waiting for data. |
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96 | |
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97 | If an EOF condition has been detected but no C<on_eof> callback has been |
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98 | set, then a fatal error will be raised with C<$!> set to <0>. |
87 | |
99 | |
88 | =item on_error => $cb->($handle, $fatal) |
100 | =item on_error => $cb->($handle, $fatal) |
89 | |
101 | |
90 | This is the error callback, which is called when, well, some error |
102 | This is the error callback, which is called when, well, some error |
91 | occured, such as not being able to resolve the hostname, failure to |
103 | occured, such as not being able to resolve the hostname, failure to |
92 | connect or a read error. |
104 | connect or a read error. |
93 | |
105 | |
94 | Some errors are fatal (which is indicated by C<$fatal> being true). On |
106 | Some errors are fatal (which is indicated by C<$fatal> being true). On |
95 | fatal errors the handle object will be shut down and will not be |
107 | fatal errors the handle object will be shut down and will not be usable |
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108 | (but you are free to look at the current C< ->rbuf >). Examples of fatal |
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109 | errors are an EOF condition with active (but unsatisifable) read watchers |
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110 | (C<EPIPE>) or I/O errors. |
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111 | |
96 | usable. Non-fatal errors can be retried by simply returning, but it is |
112 | Non-fatal errors can be retried by simply returning, but it is recommended |
97 | recommended to simply ignore this parameter and instead abondon the handle |
113 | to simply ignore this parameter and instead abondon the handle object |
98 | object when this callback is invoked. |
114 | when this callback is invoked. Examples of non-fatal errors are timeouts |
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115 | C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>). |
99 | |
116 | |
100 | On callback entrance, the value of C<$!> contains the operating system |
117 | On callback entrance, the value of C<$!> contains the operating system |
101 | error (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT> or C<EBADMSG>). |
118 | error (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT> or C<EBADMSG>). |
102 | |
119 | |
103 | While not mandatory, it is I<highly> recommended to set this callback, as |
120 | While not mandatory, it is I<highly> recommended to set this callback, as |
… | |
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210 | This will not work for partial TLS data that could not yet been |
227 | This will not work for partial TLS data that could not yet been |
211 | encoded. This data will be lost. |
228 | encoded. This data will be lost. |
212 | |
229 | |
213 | =item tls => "accept" | "connect" | Net::SSLeay::SSL object |
230 | =item tls => "accept" | "connect" | Net::SSLeay::SSL object |
214 | |
231 | |
215 | When this parameter is given, it enables TLS (SSL) mode, that means it |
232 | When this parameter is given, it enables TLS (SSL) mode, that means |
216 | will start making tls handshake and will transparently encrypt/decrypt |
233 | AnyEvent will start a TLS handshake and will transparently encrypt/decrypt |
217 | data. |
234 | data. |
218 | |
235 | |
219 | TLS mode requires Net::SSLeay to be installed (it will be loaded |
236 | TLS mode requires Net::SSLeay to be installed (it will be loaded |
220 | automatically when you try to create a TLS handle). |
237 | automatically when you try to create a TLS handle). |
221 | |
238 | |
222 | For the TLS server side, use C<accept>, and for the TLS client side of a |
239 | Unlike TCP, TLS has a server and client side: for the TLS server side, use |
223 | connection, use C<connect> mode. |
240 | C<accept>, and for the TLS client side of a connection, use C<connect> |
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241 | mode. |
224 | |
242 | |
225 | You can also provide your own TLS connection object, but you have |
243 | You can also provide your own TLS connection object, but you have |
226 | to make sure that you call either C<Net::SSLeay::set_connect_state> |
244 | to make sure that you call either C<Net::SSLeay::set_connect_state> |
227 | or C<Net::SSLeay::set_accept_state> on it before you pass it to |
245 | or C<Net::SSLeay::set_accept_state> on it before you pass it to |
228 | AnyEvent::Handle. |
246 | AnyEvent::Handle. |
229 | |
247 | |
230 | See the C<starttls> method if you need to start TLs negotiation later. |
248 | See the C<starttls> method for when need to start TLS negotiation later. |
231 | |
249 | |
232 | =item tls_ctx => $ssl_ctx |
250 | =item tls_ctx => $ssl_ctx |
233 | |
251 | |
234 | Use the given Net::SSLeay::CTX object to create the new TLS connection |
252 | Use the given Net::SSLeay::CTX object to create the new TLS connection |
235 | (unless a connection object was specified directly). If this parameter is |
253 | (unless a connection object was specified directly). If this parameter is |
… | |
… | |
238 | =item json => JSON or JSON::XS object |
256 | =item json => JSON or JSON::XS object |
239 | |
257 | |
240 | This is the json coder object used by the C<json> read and write types. |
258 | This is the json coder object used by the C<json> read and write types. |
241 | |
259 | |
242 | If you don't supply it, then AnyEvent::Handle will create and use a |
260 | If you don't supply it, then AnyEvent::Handle will create and use a |
243 | suitable one, which will write and expect UTF-8 encoded JSON texts. |
261 | suitable one (on demand), which will write and expect UTF-8 encoded JSON |
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262 | texts. |
244 | |
263 | |
245 | Note that you are responsible to depend on the JSON module if you want to |
264 | Note that you are responsible to depend on the JSON module if you want to |
246 | use this functionality, as AnyEvent does not have a dependency itself. |
265 | use this functionality, as AnyEvent does not have a dependency itself. |
247 | |
266 | |
248 | =item filter_r => $cb |
267 | =item filter_r => $cb |
249 | |
268 | |
250 | =item filter_w => $cb |
269 | =item filter_w => $cb |
251 | |
270 | |
252 | These exist, but are undocumented at this time. |
271 | These exist, but are undocumented at this time. (They are used internally |
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272 | by the TLS code). |
253 | |
273 | |
254 | =back |
274 | =back |
255 | |
275 | |
256 | =cut |
276 | =cut |
257 | |
277 | |
… | |
… | |
288 | delete $self->{_rw}; |
308 | delete $self->{_rw}; |
289 | delete $self->{_ww}; |
309 | delete $self->{_ww}; |
290 | delete $self->{fh}; |
310 | delete $self->{fh}; |
291 | |
311 | |
292 | $self->stoptls; |
312 | $self->stoptls; |
|
|
313 | |
|
|
314 | delete $self->{on_read}; |
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|
315 | delete $self->{_queue}; |
293 | } |
316 | } |
294 | |
317 | |
295 | sub _error { |
318 | sub _error { |
296 | my ($self, $errno, $fatal) = @_; |
319 | my ($self, $errno, $fatal) = @_; |
297 | |
320 | |
… | |
… | |
726 | |
749 | |
727 | if ( |
750 | if ( |
728 | defined $self->{rbuf_max} |
751 | defined $self->{rbuf_max} |
729 | && $self->{rbuf_max} < length $self->{rbuf} |
752 | && $self->{rbuf_max} < length $self->{rbuf} |
730 | ) { |
753 | ) { |
731 | return $self->_error (&Errno::ENOSPC, 1); |
754 | $self->_error (&Errno::ENOSPC, 1), return; |
732 | } |
755 | } |
733 | |
756 | |
734 | while () { |
757 | while () { |
735 | no strict 'refs'; |
|
|
736 | |
|
|
737 | my $len = length $self->{rbuf}; |
758 | my $len = length $self->{rbuf}; |
738 | |
759 | |
739 | if (my $cb = shift @{ $self->{_queue} }) { |
760 | if (my $cb = shift @{ $self->{_queue} }) { |
740 | unless ($cb->($self)) { |
761 | unless ($cb->($self)) { |
741 | if ($self->{_eof}) { |
762 | if ($self->{_eof}) { |
742 | # no progress can be made (not enough data and no data forthcoming) |
763 | # no progress can be made (not enough data and no data forthcoming) |
743 | $self->_error (&Errno::EPIPE, 1), last; |
764 | $self->_error (&Errno::EPIPE, 1), return; |
744 | } |
765 | } |
745 | |
766 | |
746 | unshift @{ $self->{_queue} }, $cb; |
767 | unshift @{ $self->{_queue} }, $cb; |
747 | last; |
768 | last; |
748 | } |
769 | } |
… | |
… | |
756 | && !@{ $self->{_queue} } # and the queue is still empty |
777 | && !@{ $self->{_queue} } # and the queue is still empty |
757 | && $self->{on_read} # but we still have on_read |
778 | && $self->{on_read} # but we still have on_read |
758 | ) { |
779 | ) { |
759 | # no further data will arrive |
780 | # no further data will arrive |
760 | # so no progress can be made |
781 | # so no progress can be made |
761 | $self->_error (&Errno::EPIPE, 1), last |
782 | $self->_error (&Errno::EPIPE, 1), return |
762 | if $self->{_eof}; |
783 | if $self->{_eof}; |
763 | |
784 | |
764 | last; # more data might arrive |
785 | last; # more data might arrive |
765 | } |
786 | } |
766 | } else { |
787 | } else { |
… | |
… | |
768 | delete $self->{_rw}; |
789 | delete $self->{_rw}; |
769 | last; |
790 | last; |
770 | } |
791 | } |
771 | } |
792 | } |
772 | |
793 | |
|
|
794 | if ($self->{_eof}) { |
|
|
795 | if ($self->{on_eof}) { |
773 | $self->{on_eof}($self) |
796 | $self->{on_eof}($self) |
774 | if $self->{_eof} && $self->{on_eof}; |
797 | } else { |
|
|
798 | $self->_error (0, 1); |
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|
799 | } |
|
|
800 | } |
775 | |
801 | |
776 | # may need to restart read watcher |
802 | # may need to restart read watcher |
777 | unless ($self->{_rw}) { |
803 | unless ($self->{_rw}) { |
778 | $self->start_read |
804 | $self->start_read |
779 | if $self->{on_read} || @{ $self->{_queue} }; |
805 | if $self->{on_read} || @{ $self->{_queue} }; |
… | |
… | |
905 | $cb->($_[0], substr $_[0]{rbuf}, 0, $len, ""); |
931 | $cb->($_[0], substr $_[0]{rbuf}, 0, $len, ""); |
906 | 1 |
932 | 1 |
907 | } |
933 | } |
908 | }; |
934 | }; |
909 | |
935 | |
910 | # compatibility with older API |
|
|
911 | sub push_read_chunk { |
|
|
912 | $_[0]->push_read (chunk => $_[1], $_[2]); |
|
|
913 | } |
|
|
914 | |
|
|
915 | sub unshift_read_chunk { |
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|
916 | $_[0]->unshift_read (chunk => $_[1], $_[2]); |
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|
917 | } |
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|
918 | |
|
|
919 | =item line => [$eol, ]$cb->($handle, $line, $eol) |
936 | =item line => [$eol, ]$cb->($handle, $line, $eol) |
920 | |
937 | |
921 | The callback will be called only once a full line (including the end of |
938 | The callback will be called only once a full line (including the end of |
922 | line marker, C<$eol>) has been read. This line (excluding the end of line |
939 | line marker, C<$eol>) has been read. This line (excluding the end of line |
923 | marker) will be passed to the callback as second argument (C<$line>), and |
940 | marker) will be passed to the callback as second argument (C<$line>), and |
… | |
… | |
938 | =cut |
955 | =cut |
939 | |
956 | |
940 | register_read_type line => sub { |
957 | register_read_type line => sub { |
941 | my ($self, $cb, $eol) = @_; |
958 | my ($self, $cb, $eol) = @_; |
942 | |
959 | |
943 | $eol = qr|(\015?\012)| if @_ < 3; |
960 | if (@_ < 3) { |
|
|
961 | # this is more than twice as fast as the generic code below |
|
|
962 | sub { |
|
|
963 | $_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return; |
|
|
964 | |
|
|
965 | $cb->($_[0], $1, $2); |
|
|
966 | 1 |
|
|
967 | } |
|
|
968 | } else { |
944 | $eol = quotemeta $eol unless ref $eol; |
969 | $eol = quotemeta $eol unless ref $eol; |
945 | $eol = qr|^(.*?)($eol)|s; |
970 | $eol = qr|^(.*?)($eol)|s; |
946 | |
971 | |
947 | sub { |
972 | sub { |
948 | $_[0]{rbuf} =~ s/$eol// or return; |
973 | $_[0]{rbuf} =~ s/$eol// or return; |
949 | |
974 | |
950 | $cb->($_[0], $1, $2); |
975 | $cb->($_[0], $1, $2); |
|
|
976 | 1 |
951 | 1 |
977 | } |
952 | } |
978 | } |
953 | }; |
979 | }; |
954 | |
|
|
955 | # compatibility with older API |
|
|
956 | sub push_read_line { |
|
|
957 | my $self = shift; |
|
|
958 | $self->push_read (line => @_); |
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|
959 | } |
|
|
960 | |
|
|
961 | sub unshift_read_line { |
|
|
962 | my $self = shift; |
|
|
963 | $self->unshift_read (line => @_); |
|
|
964 | } |
|
|
965 | |
980 | |
966 | =item regex => $accept[, $reject[, $skip], $cb->($handle, $data) |
981 | =item regex => $accept[, $reject[, $skip], $cb->($handle, $data) |
967 | |
982 | |
968 | Makes a regex match against the regex object C<$accept> and returns |
983 | Makes a regex match against the regex object C<$accept> and returns |
969 | everything up to and including the match. |
984 | everything up to and including the match. |
… | |
… | |
1090 | register_read_type packstring => sub { |
1105 | register_read_type packstring => sub { |
1091 | my ($self, $cb, $format) = @_; |
1106 | my ($self, $cb, $format) = @_; |
1092 | |
1107 | |
1093 | sub { |
1108 | sub { |
1094 | # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method |
1109 | # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method |
1095 | defined (my $len = eval { unpack $format, $_[0]->{rbuf} }) |
1110 | defined (my $len = eval { unpack $format, $_[0]{rbuf} }) |
1096 | or return; |
1111 | or return; |
1097 | |
1112 | |
|
|
1113 | $format = length pack $format, $len; |
|
|
1114 | |
|
|
1115 | # bypass unshift if we already have the remaining chunk |
|
|
1116 | if ($format + $len <= length $_[0]{rbuf}) { |
|
|
1117 | my $data = substr $_[0]{rbuf}, $format, $len; |
|
|
1118 | substr $_[0]{rbuf}, 0, $format + $len, ""; |
|
|
1119 | $cb->($_[0], $data); |
|
|
1120 | } else { |
1098 | # remove prefix |
1121 | # remove prefix |
1099 | substr $_[0]->{rbuf}, 0, (length pack $format, $len), ""; |
1122 | substr $_[0]{rbuf}, 0, $format, ""; |
1100 | |
1123 | |
1101 | # read rest |
1124 | # read remaining chunk |
1102 | $_[0]->unshift_read (chunk => $len, $cb); |
1125 | $_[0]->unshift_read (chunk => $len, $cb); |
|
|
1126 | } |
1103 | |
1127 | |
1104 | 1 |
1128 | 1 |
1105 | } |
1129 | } |
1106 | }; |
1130 | }; |
1107 | |
1131 | |
… | |
… | |
1164 | |
1188 | |
1165 | require Storable; |
1189 | require Storable; |
1166 | |
1190 | |
1167 | sub { |
1191 | sub { |
1168 | # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method |
1192 | # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method |
1169 | defined (my $len = eval { unpack "w", $_[0]->{rbuf} }) |
1193 | defined (my $len = eval { unpack "w", $_[0]{rbuf} }) |
1170 | or return; |
1194 | or return; |
1171 | |
1195 | |
|
|
1196 | my $format = length pack "w", $len; |
|
|
1197 | |
|
|
1198 | # bypass unshift if we already have the remaining chunk |
|
|
1199 | if ($format + $len <= length $_[0]{rbuf}) { |
|
|
1200 | my $data = substr $_[0]{rbuf}, $format, $len; |
|
|
1201 | substr $_[0]{rbuf}, 0, $format + $len, ""; |
|
|
1202 | $cb->($_[0], Storable::thaw ($data)); |
|
|
1203 | } else { |
1172 | # remove prefix |
1204 | # remove prefix |
1173 | substr $_[0]->{rbuf}, 0, (length pack "w", $len), ""; |
1205 | substr $_[0]{rbuf}, 0, $format, ""; |
1174 | |
1206 | |
1175 | # read rest |
1207 | # read remaining chunk |
1176 | $_[0]->unshift_read (chunk => $len, sub { |
1208 | $_[0]->unshift_read (chunk => $len, sub { |
1177 | if (my $ref = eval { Storable::thaw ($_[1]) }) { |
1209 | if (my $ref = eval { Storable::thaw ($_[1]) }) { |
1178 | $cb->($_[0], $ref); |
1210 | $cb->($_[0], $ref); |
1179 | } else { |
1211 | } else { |
1180 | $self->_error (&Errno::EBADMSG); |
1212 | $self->_error (&Errno::EBADMSG); |
|
|
1213 | } |
1181 | } |
1214 | }); |
1182 | }); |
1215 | } |
|
|
1216 | |
|
|
1217 | 1 |
1183 | } |
1218 | } |
1184 | }; |
1219 | }; |
1185 | |
1220 | |
1186 | =back |
1221 | =back |
1187 | |
1222 | |
… | |
… | |
1333 | # basically, this is deep magic (because SSL_read should have the same issues) |
1368 | # basically, this is deep magic (because SSL_read should have the same issues) |
1334 | # but the openssl maintainers basically said: "trust us, it just works". |
1369 | # but the openssl maintainers basically said: "trust us, it just works". |
1335 | # (unfortunately, we have to hardcode constants because the abysmally misdesigned |
1370 | # (unfortunately, we have to hardcode constants because the abysmally misdesigned |
1336 | # and mismaintained ssleay-module doesn't even offer them). |
1371 | # and mismaintained ssleay-module doesn't even offer them). |
1337 | # http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html |
1372 | # http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html |
|
|
1373 | # |
|
|
1374 | # in short: this is a mess. |
|
|
1375 | # |
|
|
1376 | # note that we do not try to kepe the length constant between writes as we are required to do. |
|
|
1377 | # we assume that most (but not all) of this insanity only applies to non-blocking cases, |
|
|
1378 | # and we drive openssl fully in blocking mode here. |
1338 | Net::SSLeay::CTX_set_mode ($self->{tls}, |
1379 | Net::SSLeay::CTX_set_mode ($self->{tls}, |
1339 | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1) |
1380 | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1) |
1340 | | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2)); |
1381 | | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2)); |
1341 | |
1382 | |
1342 | $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); |
1383 | $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); |
… | |
… | |
1448 | =over 4 |
1489 | =over 4 |
1449 | |
1490 | |
1450 | =item * all constructor arguments become object members. |
1491 | =item * all constructor arguments become object members. |
1451 | |
1492 | |
1452 | At least initially, when you pass a C<tls>-argument to the constructor it |
1493 | At least initially, when you pass a C<tls>-argument to the constructor it |
1453 | will end up in C<< $handle->{tls} >>. Those members might be changes or |
1494 | will end up in C<< $handle->{tls} >>. Those members might be changed or |
1454 | mutated later on (for example C<tls> will hold the TLS connection object). |
1495 | mutated later on (for example C<tls> will hold the TLS connection object). |
1455 | |
1496 | |
1456 | =item * other object member names are prefixed with an C<_>. |
1497 | =item * other object member names are prefixed with an C<_>. |
1457 | |
1498 | |
1458 | All object members not explicitly documented (internal use) are prefixed |
1499 | All object members not explicitly documented (internal use) are prefixed |