More robust yacc/bison failure output handling.
[p5sagit/p5-mst-13.2.git] / lib / chat2.pl
CommitLineData
3e3baf6d 1# chat.pl: chat with a server
2# Based on: V2.01.alpha.7 91/06/16
3# Randal L. Schwartz (was <merlyn@stonehenge.com>)
4# multihome additions by A.Macpherson@bnr.co.uk
5# allow for /dev/pts based systems by Joe Doupnik <JRD@CC.USU.EDU>
6
7package chat;
8
9require 'sys/socket.ph';
10
11if( defined( &main'PF_INET ) ){
12 $pf_inet = &main'PF_INET;
13 $sock_stream = &main'SOCK_STREAM;
14 local($name, $aliases, $proto) = getprotobyname( 'tcp' );
15 $tcp_proto = $proto;
16}
17else {
18 # XXX hardwired $PF_INET, $SOCK_STREAM, 'tcp'
19 # but who the heck would change these anyway? (:-)
20 $pf_inet = 2;
21 $sock_stream = 1;
22 $tcp_proto = 6;
23}
24
25
26$sockaddr = 'S n a4 x8';
27chop($thishost = `hostname`);
28
29# *S = symbol for current I/O, gets assigned *chatsymbol....
30$next = "chatsymbol000000"; # next one
31$nextpat = "^chatsymbol"; # patterns that match next++, ++, ++, ++
32
33
34## $handle = &chat'open_port("server.address",$port_number);
35## opens a named or numbered TCP server
36
37sub open_port { ## public
38 local($server, $port) = @_;
39
40 local($serveraddr,$serverproc);
41
42 # We may be multi-homed, start with 0, fixup once connexion is made
43 $thisaddr = "\0\0\0\0" ;
44 $thisproc = pack($sockaddr, 2, 0, $thisaddr);
45
46 *S = ++$next;
47 if ($server =~ /^(\d+)+\.(\d+)\.(\d+)\.(\d+)$/) {
48 $serveraddr = pack('C4', $1, $2, $3, $4);
49 } else {
50 local(@x) = gethostbyname($server);
51 return undef unless @x;
52 $serveraddr = $x[4];
53 }
54 $serverproc = pack($sockaddr, 2, $port, $serveraddr);
55 unless (socket(S, $pf_inet, $sock_stream, $tcp_proto)) {
56 ($!) = ($!, close(S)); # close S while saving $!
57 return undef;
58 }
59 unless (bind(S, $thisproc)) {
60 ($!) = ($!, close(S)); # close S while saving $!
61 return undef;
62 }
63 unless (connect(S, $serverproc)) {
64 ($!) = ($!, close(S)); # close S while saving $!
65 return undef;
66 }
67# We opened with the local address set to ANY, at this stage we know
68# which interface we are using. This is critical if our machine is
69# multi-homed, with IP forwarding off, so fix-up.
70 local($fam,$lport);
71 ($fam,$lport,$thisaddr) = unpack($sockaddr, getsockname(S));
72 $thisproc = pack($sockaddr, 2, 0, $thisaddr);
73# end of post-connect fixup
74 select((select(S), $| = 1)[0]);
75 $next; # return symbol for switcharound
76}
77
78## ($host, $port, $handle) = &chat'open_listen([$port_number]);
79## opens a TCP port on the current machine, ready to be listened to
80## if $port_number is absent or zero, pick a default port number
81## process must be uid 0 to listen to a low port number
82
83sub open_listen { ## public
84
85 *S = ++$next;
86 local($thisport) = shift || 0;
87 local($thisproc_local) = pack($sockaddr, 2, $thisport, $thisaddr);
88 local(*NS) = "__" . time;
89 unless (socket(NS, $pf_inet, $sock_stream, $tcp_proto)) {
90 ($!) = ($!, close(NS));
91 return undef;
92 }
93 unless (bind(NS, $thisproc_local)) {
94 ($!) = ($!, close(NS));
95 return undef;
96 }
97 unless (listen(NS, 1)) {
98 ($!) = ($!, close(NS));
99 return undef;
100 }
101 select((select(NS), $| = 1)[0]);
102 local($family, $port, @myaddr) =
103 unpack("S n C C C C x8", getsockname(NS));
104 $S{"needs_accept"} = *NS; # so expect will open it
105 (@myaddr, $port, $next); # returning this
106}
107
108## $handle = &chat'open_proc("command","arg1","arg2",...);
109## opens a /bin/sh on a pseudo-tty
110
111sub open_proc { ## public
112 local(@cmd) = @_;
113
114 *S = ++$next;
115 local(*TTY) = "__TTY" . time;
116 local($pty,$tty) = &_getpty(S,TTY);
117 die "Cannot find a new pty" unless defined $pty;
118 $pid = fork;
119 die "Cannot fork: $!" unless defined $pid;
120 unless ($pid) {
121 close STDIN; close STDOUT; close STDERR;
122 setpgrp(0,$$);
123 if (open(DEVTTY, "/dev/tty")) {
124 ioctl(DEVTTY,0x20007471,0); # XXX s/b &TIOCNOTTY
125 close DEVTTY;
126 }
127 open(STDIN,"<&TTY");
128 open(STDOUT,">&TTY");
129 open(STDERR,">&STDOUT");
130 die "Oops" unless fileno(STDERR) == 2; # sanity
131 close(S);
132 exec @cmd;
133 die "Cannot exec @cmd: $!";
134 }
135 close(TTY);
136 $next; # return symbol for switcharound
137}
138
139# $S is the read-ahead buffer
140
141## $return = &chat'expect([$handle,] $timeout_time,
142## $pat1, $body1, $pat2, $body2, ... )
143## $handle is from previous &chat'open_*().
144## $timeout_time is the time (either relative to the current time, or
145## absolute, ala time(2)) at which a timeout event occurs.
146## $pat1, $pat2, and so on are regexs which are matched against the input
147## stream. If a match is found, the entire matched string is consumed,
148## and the corresponding body eval string is evaled.
149##
150## Each pat is a regular-expression (probably enclosed in single-quotes
151## in the invocation). ^ and $ will work, respecting the current value of $*.
152## If pat is 'TIMEOUT', the body is executed if the timeout is exceeded.
153## If pat is 'EOF', the body is executed if the process exits before
154## the other patterns are seen.
155##
156## Pats are scanned in the order given, so later pats can contain
157## general defaults that won't be examined unless the earlier pats
158## have failed.
159##
160## The result of eval'ing body is returned as the result of
161## the invocation. Recursive invocations are not thought
162## through, and may work only accidentally. :-)
163##
164## undef is returned if either a timeout or an eof occurs and no
165## corresponding body has been defined.
166## I/O errors of any sort are treated as eof.
167
168$nextsubname = "expectloop000000"; # used for subroutines
169
170sub expect { ## public
171 if ($_[0] =~ /$nextpat/) {
172 *S = shift;
173 }
174 local($endtime) = shift;
175
176 local($timeout,$eof) = (1,1);
177 local($caller) = caller;
178 local($rmask, $nfound, $timeleft, $thisbuf);
179 local($cases, $pattern, $action, $subname);
180 $endtime += time if $endtime < 600_000_000;
181
182 if (defined $S{"needs_accept"}) { # is it a listen socket?
183 local(*NS) = $S{"needs_accept"};
184 delete $S{"needs_accept"};
185 $S{"needs_close"} = *NS;
186 unless(accept(S,NS)) {
187 ($!) = ($!, close(S), close(NS));
188 return undef;
189 }
190 select((select(S), $| = 1)[0]);
191 }
192
193 # now see whether we need to create a new sub:
194
195 unless ($subname = $expect_subname{$caller,@_}) {
196 # nope. make a new one:
197 $expect_subname{$caller,@_} = $subname = $nextsubname++;
198
199 $cases .= <<"EDQ"; # header is funny to make everything elsif's
200sub $subname {
201 LOOP: {
202 if (0) { ; }
203EDQ
204 while (@_) {
205 ($pattern,$action) = splice(@_,0,2);
206 if ($pattern =~ /^eof$/i) {
207 $cases .= <<"EDQ";
208 elsif (\$eof) {
209 package $caller;
210 $action;
211 }
212EDQ
213 $eof = 0;
214 } elsif ($pattern =~ /^timeout$/i) {
215 $cases .= <<"EDQ";
216 elsif (\$timeout) {
217 package $caller;
218 $action;
219 }
220EDQ
221 $timeout = 0;
222 } else {
223 $pattern =~ s#/#\\/#g;
224 $cases .= <<"EDQ";
225 elsif (\$S =~ /$pattern/) {
226 \$S = \$';
227 package $caller;
228 $action;
229 }
230EDQ
231 }
232 }
233 $cases .= <<"EDQ" if $eof;
234 elsif (\$eof) {
235 undef;
236 }
237EDQ
238 $cases .= <<"EDQ" if $timeout;
239 elsif (\$timeout) {
240 undef;
241 }
242EDQ
243 $cases .= <<'ESQ';
244 else {
245 $rmask = "";
246 vec($rmask,fileno(S),1) = 1;
247 ($nfound, $rmask) =
248 select($rmask, undef, undef, $endtime - time);
249 if ($nfound) {
250 $nread = sysread(S, $thisbuf, 1024);
251 if ($nread > 0) {
252 $S .= $thisbuf;
253 } else {
254 $eof++, redo LOOP; # any error is also eof
255 }
256 } else {
257 $timeout++, redo LOOP; # timeout
258 }
259 redo LOOP;
260 }
261 }
262}
263ESQ
264 eval $cases; die "$cases:\n$@" if $@;
265 }
266 $eof = $timeout = 0;
267 do $subname();
268}
269
270## &chat'print([$handle,] @data)
271## $handle is from previous &chat'open().
272## like print $handle @data
273
274sub print { ## public
275 if ($_[0] =~ /$nextpat/) {
276 *S = shift;
277 }
b7b1864f 278
279 local $out = join $, , @_;
280 syswrite(S, $out, length $out);
3e3baf6d 281 if( $chat'debug ){
282 print STDERR "printed:";
283 print STDERR @_;
284 }
285}
286
287## &chat'close([$handle,])
288## $handle is from previous &chat'open().
289## like close $handle
290
291sub close { ## public
292 if ($_[0] =~ /$nextpat/) {
293 *S = shift;
294 }
295 close(S);
296 if (defined $S{"needs_close"}) { # is it a listen socket?
297 local(*NS) = $S{"needs_close"};
298 delete $S{"needs_close"};
299 close(NS);
300 }
301}
302
303## @ready_handles = &chat'select($timeout, @handles)
304## select()'s the handles with a timeout value of $timeout seconds.
305## Returns an array of handles that are ready for I/O.
306## Both user handles and chat handles are supported (but beware of
307## stdio's buffering for user handles).
308
309sub select { ## public
310 local($timeout) = shift;
311 local(@handles) = @_;
312 local(%handlename) = ();
313 local(%ready) = ();
314 local($caller) = caller;
315 local($rmask) = "";
316 for (@handles) {
317 if (/$nextpat/o) { # one of ours... see if ready
318 local(*SYM) = $_;
319 if (length($SYM)) {
320 $timeout = 0; # we have a winner
321 $ready{$_}++;
322 }
323 $handlename{fileno($_)} = $_;
324 } else {
325 $handlename{fileno(/'/ ? $_ : "$caller\'$_")} = $_;
326 }
327 }
328 for (sort keys %handlename) {
329 vec($rmask, $_, 1) = 1;
330 }
331 select($rmask, undef, undef, $timeout);
332 for (sort keys %handlename) {
333 $ready{$handlename{$_}}++ if vec($rmask,$_,1);
334 }
335 sort keys %ready;
336}
337
338# ($pty,$tty) = $chat'_getpty(PTY,TTY):
339# internal procedure to get the next available pty.
340# opens pty on handle PTY, and matching tty on handle TTY.
341# returns undef if can't find a pty.
342# Modify "/dev/pty" to "/dev/pts" for Dell Unix v2.2 (aka SVR4.04). Joe Doupnik.
343
344sub _getpty { ## private
345 local($_PTY,$_TTY) = @_;
346 $_PTY =~ s/^([^']+)$/(caller)[$[]."'".$1/e;
347 $_TTY =~ s/^([^']+)$/(caller)[$[]."'".$1/e;
348 local($pty, $tty, $kind);
349 if( -e "/dev/pts000" ){ ## mods by Joe Doupnik Dec 1992
350 $kind = "pts"; ## SVR4 Streams
351 } else {
352 $kind = "pty"; ## BSD Clist stuff
353 }
354 for $bank (112..127) {
355 next unless -e sprintf("/dev/$kind%c0", $bank);
356 for $unit (48..57) {
357 $pty = sprintf("/dev/$kind%c%c", $bank, $unit);
358 open($_PTY,"+>$pty") || next;
359 select((select($_PTY), $| = 1)[0]);
360 ($tty = $pty) =~ s/pty/tty/;
361 open($_TTY,"+>$tty") || next;
362 select((select($_TTY), $| = 1)[0]);
363 system "stty nl>$tty";
364 return ($pty,$tty);
365 }
366 }
367 undef;
368}
369
3701;