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Text File | 1993-11-12 | 7.1 KB | 293 lines | [TEXT/MPS ] |
- ## macchat.pl: chat with a server over any protocol
- ## Matthias Neeracher
-
- ## Derived from chat2pl
- ## V2.01.alpha.7 91/06/16
- ## Randal L. Schwartz
-
- package macchat;
-
- require 'GUSI.ph';
-
- # *S = symbol for current I/O, gets assigned *chatsymbol....
- $next = "chatsymbol000000"; # next one
- $nextpat = "^chatsymbol"; # patterns that match next++, ++, ++, ++
-
-
- ## $handle = &chat'open_port($family, $addr [, $ouraddr]);
- ## opens a named or numbered server.
- ## $addr may be created with one of the pack_sockaddr… routines in GUSI.pl
-
- sub open_port { ## public
- local($family, $addr, $ouraddr) = @_;
-
- *S = ++$next;
- unless (socket(S, $family, &GUSI'SOCK_STREAM, 0)) {
- ($!) = ($!, close(S)); # close S while saving $!
- return undef;
- }
- if (defined($ouraddr)) {
- unless (bind(S, $ouraddr)) {
- ($!) = ($!, close(S)); # close S while saving $!
- return undef;
- }
- }
- unless (connect(S, $addr)) {
- ($!) = ($!, close(S)); # close S while saving $!
- return undef;
- }
- select((select(S), $| = 1)[0]);
- $next; # return symbol for switcharound
- }
-
- ## ($addr, $handle) = &chat'open_listen($family, [$ouraddr]);
- ## opens a TCP port on the current machine, ready to be listened to
- ## if $port_number is absent or zero, pick a default port number
- ## process must be uid 0 to listen to a low port number
-
- sub open_listen { ## public
-
- *S = ++$next;
- local($family, $ouraddr) = @_;
- local(*NS) = "__" . time;
- unless (socket(NS, $family, &GUSI'SOCK_STREAM, 0)) {
- ($!) = ($!, close(NS));
- return undef;
- }
- if (defined $ouraddr) {
- unless (bind(NS, $ouraddr)) {
- ($!) = ($!, close(NS));
- return undef;
- }
- }
- unless (listen(NS, 1)) {
- ($!) = ($!, close(NS));
- return undef;
- }
- select((select(NS), $| = 1)[0]);
- $S{"needs_accept"} = *NS; # so expect will open it
- (getsockname(NS), $next); # returning this
- }
-
- # $S is the read-ahead buffer
-
- ## $return = &chat'expect([$handle,] $timeout_time,
- ## $pat1, $body1, $pat2, $body2, ... )
- ## $handle is from previous &chat'open_*().
- ## $timeout_time is the time (either relative to the current time, or
- ## absolute, ala time(2)) at which a timeout event occurs.
- ## $pat1, $pat2, and so on are regexs which are matched against the input
- ## stream. If a match is found, the entire matched string is consumed,
- ## and the corresponding body eval string is evaled.
- ##
- ## Each pat is a regular-expression (probably enclosed in single-quotes
- ## in the invocation). ^ and $ will work, respecting the current value of $*.
- ## If pat is 'TIMEOUT', the body is executed if the timeout is exceeded.
- ## If pat is 'EOF', the body is executed if the process exits before
- ## the other patterns are seen.
- ##
- ## Pats are scanned in the order given, so later pats can contain
- ## general defaults that won't be examined unless the earlier pats
- ## have failed.
- ##
- ## The result of eval'ing body is returned as the result of
- ## the invocation. Recursive invocations are not thought
- ## through, and may work only accidentally. :-)
- ##
- ## undef is returned if either a timeout or an eof occurs and no
- ## corresponding body has been defined.
- ## I/O errors of any sort are treated as eof.
-
- $nextsubname = "expectloop000000"; # used for subroutines
-
- sub expect { ## public
- if ($_[0] =~ /$nextpat/) {
- *S = shift;
- }
- local($endtime) = shift;
-
- local($timeout,$eof) = (1,1);
- local($caller) = caller;
- local($rmask, $nfound, $timeleft, $thisbuf);
- local($cases, $pattern, $action, $subname);
- $endtime += time if $endtime < 600_000_000;
-
- if (defined $S{"needs_accept"}) { # is it a listen socket?
- local(*NS) = $S{"needs_accept"};
- delete $S{"needs_accept"};
- $S{"needs_close"} = *NS;
- unless(accept(S,NS)) {
- ($!) = ($!, close(S), close(NS));
- return undef;
- }
- select((select(S), $| = 1)[0]);
- }
-
- # now see whether we need to create a new sub:
-
- unless ($subname = $expect_subname{$caller,@_}) {
- # nope. make a new one:
- $expect_subname{$caller,@_} = $subname = $nextsubname++;
-
- $cases .= <<"EDQ"; # header is funny to make everything elsif's
- sub $subname {
- LOOP: {
- if (0) { ; }
- EDQ
- while (@_) {
- ($pattern,$action) = splice(@_,0,2);
- if ($pattern =~ /^eof$/i) {
- $cases .= <<"EDQ";
- elsif (\$eof) {
- package $caller;
- $action;
- }
- EDQ
- $eof = 0;
- } elsif ($pattern =~ /^timeout$/i) {
- $cases .= <<"EDQ";
- elsif (\$timeout) {
- package $caller;
- $action;
- }
- EDQ
- $timeout = 0;
- } else {
- $pattern =~ s#/#\\/#g;
- $cases .= <<"EDQ";
- elsif (\$S =~ /$pattern/) {
- \$S = \$';
- package $caller;
- $action;
- }
- EDQ
- }
- }
- $cases .= <<"EDQ" if $eof;
- elsif (\$eof) {
- undef;
- }
- EDQ
- $cases .= <<"EDQ" if $timeout;
- elsif (\$timeout) {
- undef;
- }
- EDQ
- $cases .= <<'ESQ';
- else {
- $rmask = "";
- vec($rmask,fileno(S),1) = 1;
- ($nfound, $rmask) =
- select($rmask, undef, undef, $endtime - time);
- if ($nfound) {
- $nread = sysread(S, $thisbuf, 1024);
- if ($nread > 0) {
- $S .= $thisbuf;
- } else {
- $eof++, redo LOOP; # any error is also eof
- }
- } else {
- $timeout++, redo LOOP; # timeout
- }
- redo LOOP;
- }
- }
- }
- ESQ
- eval $cases; die "$cases:\n$@" if $@;
- }
- $eof = $timeout = 0;
- do $subname();
- }
-
- ## &chat'print([$handle,] @data)
- ## $handle is from previous &chat'open().
- ## like print $handle @data
-
- sub print { ## public
- if ($_[0] =~ /$nextpat/) {
- *S = shift;
- }
-
- if (defined $S{"needs_accept"}) { # is it a listen socket?
- local(*NS) = $S{"needs_accept"};
- delete $S{"needs_accept"};
- $S{"needs_close"} = *NS;
- unless(accept(S,NS)) {
- ($!) = ($!, close(S), close(NS));
- return undef;
- }
- select((select(S), $| = 1)[0]);
- }
-
- print S @_;
- }
-
- ## &chat'close([$handle,])
- ## $handle is from previous &chat'open().
- ## like close $handle
-
- sub close { ## public
- local($pid);
- if ($_[0] =~ /$nextpat/) {
- $pid = $PID{$_[0]};
- *S = shift;
- } else {
- $pid = $PID{$next};
- }
- close(S);
- if (defined $S{"needs_close"}) { # is it a listen socket?
- local(*NS) = $S{"needs_close"};
- delete $S{"needs_close"};
- close(NS);
- }
- }
-
- ## @ready_handles = &chat'select($timeout, @handles)
- ## select()'s the handles with a timeout value of $timeout seconds.
- ## Returns an array of handles that are ready for I/O.
- ## Both user handles and chat handles are supported (but beware of
- ## stdio's buffering for user handles).
-
- sub select { ## public
- local($timeout) = shift;
- local(@handles) = @_;
- local(%handlename) = ();
- local(%ready) = ();
- local($caller) = caller;
- local($rmask) = "";
- for (@handles) {
- if (/$nextpat/o) { # one of ours... see if ready
- local(*SYM) = $_;
- if (defined $SYM{"needs_accept"}) { # is it a listen socket?
- local(*NS) = $SYM{"needs_accept"};
- delete $SYM{"needs_accept"};
- $SYM{"needs_close"} = *NS;
- unless(accept(SYM,NS)) {
- ($!) = ($!, close(SYM), close(NS));
- return undef;
- }
- select((select(SYM), $| = 1)[0]);
- }
-
- if (length($SYM)) {
- $timeout = 0; # we have a winner
- $ready{$_}++;
- }
- $handlename{fileno($_)} = $_;
- } else {
- $handlename{fileno(/'/ ? $_ : "$caller\'$_")} = $_;
- }
- }
- for (sort keys %handlename) {
- vec($rmask, $_, 1) = 1;
- }
- select($rmask, undef, undef, $timeout);
- for (sort keys %handlename) {
- $ready{$handlename{$_}}++ if vec($rmask,$_,1);
- }
- sort keys %ready;
- }
-
- 1;
-