lib/perl5/5.6.1/Term/Cap.pm

   1 package Term::Cap;
   2 use Carp;
   3
   4 # Last updated: Thu Dec 14 20:02:42 CST 1995 by sanders@bsdi.com
   5
   6 # TODO:
   7 # support Berkeley DB termcaps
   8 # should probably be a .xs module
   9 # force $FH into callers package?
  10 # keep $FH in object at Tgetent time?
  11
  12 =head1 NAME
  13
  14 Term::Cap - Perl termcap interface
  15
  16 =head1 SYNOPSIS
  17
  18     require Term::Cap;
  19     $terminal = Tgetent Term::Cap { TERM => undef, OSPEED => $ospeed };
  20     $terminal->Trequire(qw/ce ku kd/);
  21     $terminal->Tgoto('cm', $col, $row, $FH);
  22     $terminal->Tputs('dl', $count, $FH);
  23     $terminal->Tpad($string, $count, $FH);
  24
  25 =head1 DESCRIPTION
  26
  27 These are low-level functions to extract and use capabilities from
  28 a terminal capability (termcap) database.
  29
  30 The B<Tgetent> function extracts the entry of the specified terminal
  31 type I<TERM> (defaults to the environment variable I<TERM>) from the
  32 database.
  33
  34 It will look in the environment for a I<TERMCAP> variable.  If
  35 found, and the value does not begin with a slash, and the terminal
  36 type name is the same as the environment string I<TERM>, the
  37 I<TERMCAP> string is used instead of reading a termcap file.  If
  38 it does begin with a slash, the string is used as a path name of
  39 the termcap file to search.  If I<TERMCAP> does not begin with a
  40 slash and name is different from I<TERM>, B<Tgetent> searches the
  41 files F<$HOME/.termcap>, F</etc/termcap>, and F</usr/share/misc/termcap>,
  42 in that order, unless the environment variable I<TERMPATH> exists,
  43 in which case it specifies a list of file pathnames (separated by
  44 spaces or colons) to be searched B<instead>.  Whenever multiple
  45 files are searched and a tc field occurs in the requested entry,
  46 the entry it names must be found in the same file or one of the
  47 succeeding files.  If there is a C<:tc=...:> in the I<TERMCAP>
  48 environment variable string it will continue the search in the
  49 files as above.
  50
  51 I<OSPEED> is the terminal output bit rate (often mistakenly called
  52 the baud rate).  I<OSPEED> can be specified as either a POSIX
  53 termios/SYSV termio speeds (where 9600 equals 9600) or an old
  54 BSD-style speeds (where 13 equals 9600).
  55
  56 B<Tgetent> returns a blessed object reference which the user can
  57 then use to send the control strings to the terminal using B<Tputs>
  58 and B<Tgoto>.  It calls C<croak> on failure.
  59
  60 B<Tgoto> decodes a cursor addressing string with the given parameters.
  61
  62 The output strings for B<Tputs> are cached for counts of 1 for performance.
  63 B<Tgoto> and B<Tpad> do not cache.  C<$self-E<gt>{_xx}> is the raw termcap
  64 data and C<$self-E<gt>{xx}> is the cached version.
  65
  66     print $terminal->Tpad($self->{_xx}, 1);
  67
  68 B<Tgoto>, B<Tputs>, and B<Tpad> return the string and will also
  69 output the string to $FH if specified.
  70
  71 The extracted termcap entry is available in the object
  72 as C<$self-E<gt>{TERMCAP}>.
  73
  74 =head1 EXAMPLES
  75
  76     # Get terminal output speed
  77     require POSIX;
  78     my $termios = new POSIX::Termios;
  79     $termios->getattr;
  80     my $ospeed = $termios->getospeed;
  81
  82     # Old-style ioctl code to get ospeed:
  83     #     require 'ioctl.pl';
  84     #     ioctl(TTY,$TIOCGETP,$sgtty);
  85     #     ($ispeed,$ospeed) = unpack('cc',$sgtty);
  86
  87     # allocate and initialize a terminal structure
  88     $terminal = Tgetent Term::Cap { TERM => undef, OSPEED => $ospeed };
  89
  90     # require certain capabilities to be available
  91     $terminal->Trequire(qw/ce ku kd/);
  92
  93     # Output Routines, if $FH is undefined these just return the string
  94
  95     # Tgoto does the % expansion stuff with the given args
  96     $terminal->Tgoto('cm', $col, $row, $FH);
  97
  98     # Tputs doesn't do any % expansion.
  99     $terminal->Tputs('dl', $count = 1, $FH);
 100
 101 =cut
 102
 103 # Returns a list of termcap files to check.
 104 sub termcap_path { ## private
 105     my @termcap_path;
 106     # $TERMCAP, if it's a filespec
 107     push(@termcap_path, $ENV{TERMCAP})
 108         if ((exists $ENV{TERMCAP}) &&
 109             (($^O eq 'os2' || $^O eq 'MSWin32' || $^O eq 'dos')
 110              ? $ENV{TERMCAP} =~ /^[a-z]:[\\\/]/is
 111              : $ENV{TERMCAP} =~ /^\//s));
 112     if ((exists $ENV{TERMPATH}) && ($ENV{TERMPATH})) {
 113         # Add the users $TERMPATH
 114         push(@termcap_path, split(/(:|\s+)/, $ENV{TERMPATH}))
 115     }
 116     else {
 117         # Defaults
 118         push(@termcap_path,
 119             $ENV{'HOME'} . '/.termcap',
 120             '/etc/termcap',
 121             '/usr/share/misc/termcap',
 122         );
 123     }
 124     # return the list of those termcaps that exist
 125     grep(-f, @termcap_path);
 126 }
 127
 128 sub Tgetent { ## public -- static method
 129     my $class = shift;
 130     my $self = bless shift, $class;
 131     my($term,$cap,$search,$field,$max,$tmp_term,$TERMCAP);
 132     local($termpat,$state,$first,$entry);       # used inside eval
 133     local $_;
 134
 135     # Compute PADDING factor from OSPEED (to be used by Tpad)
 136     if (! $self->{OSPEED}) {
 137         carp "OSPEED was not set, defaulting to 9600";
 138         $self->{OSPEED} = 9600;
 139     }
 140     if ($self->{OSPEED} < 16) {
 141         # delays for old style speeds
 142         my @pad = (0,200,133.3,90.9,74.3,66.7,50,33.3,16.7,8.3,5.5,4.1,2,1,.5,.2);
 143         $self->{PADDING} = $pad[$self->{OSPEED}];
 144     }
 145     else {
 146         $self->{PADDING} = 10000 / $self->{OSPEED};
 147     }
 148
 149     $self->{TERM} = ($self->{TERM} || $ENV{TERM} || croak "TERM not set");
 150     $term = $self->{TERM};      # $term is the term type we are looking for
 151
 152     # $tmp_term is always the next term (possibly :tc=...:) we are looking for
 153     $tmp_term = $self->{TERM};
 154     # protect any pattern metacharacters in $tmp_term
 155     $termpat = $tmp_term; $termpat =~ s/(\W)/\\$1/g;
 156
 157     my $foo = (exists $ENV{TERMCAP} ? $ENV{TERMCAP} : '');
 158
 159     # $entry is the extracted termcap entry
 160     if (($foo !~ m:^/:s) && ($foo =~ m/(^|\|)${termpat}[:|]/s)) {
 161         $entry = $foo;
 162     }
 163
 164     my @termcap_path = termcap_path;
 165     croak "Can't find a valid termcap file" unless @termcap_path || $entry;
 166
 167     $state = 1;                                 # 0 == finished
 168                                                 # 1 == next file
 169                                                 # 2 == search again
 170
 171     $first = 0;                                 # first entry (keeps term name)
 172
 173     $max = 32;                                  # max :tc=...:'s
 174
 175     if ($entry) {
 176         # ok, we're starting with $TERMCAP
 177         $first++;                               # we're the first entry
 178         # do we need to continue?
 179         if ($entry =~ s/:tc=([^:]+):/:/) {
 180             $tmp_term = $1;
 181             # protect any pattern metacharacters in $tmp_term
 182             $termpat = $tmp_term; $termpat =~ s/(\W)/\\$1/g;
 183         }
 184         else {
 185             $state = 0;                         # we're already finished
 186         }
 187     }
 188
 189     # This is eval'ed inside the while loop for each file
 190     $search = q{
 191         while (<TERMCAP>) {
 192             next if /^\\t/ || /^#/;
 193             if ($_ =~ m/(^|\\|)${termpat}[:|]/o) {
 194                 chomp;
 195                 s/^[^:]*:// if $first++;
 196                 $state = 0;
 197                 while ($_ =~ s/\\\\$//) {
 198                     defined(my $x = <TERMCAP>) or last;
 199                     $_ .= $x; chomp;
 200                 }
 201                 last;
 202             }
 203         }
 204         defined $entry or $entry = '';
 205         $entry .= $_;
 206     };
 207
 208     while ($state != 0) {
 209         if ($state == 1) {
 210             # get the next TERMCAP
 211             $TERMCAP = shift @termcap_path
 212                 || croak "failed termcap lookup on $tmp_term";
 213         }
 214         else {
 215             # do the same file again
 216             # prevent endless recursion
 217             $max-- || croak "failed termcap loop at $tmp_term";
 218             $state = 1;         # ok, maybe do a new file next time
 219         }
 220
 221         open(TERMCAP,"< $TERMCAP\0") || croak "open $TERMCAP: $!";
 222         eval $search;
 223         die $@ if $@;
 224         close TERMCAP;
 225
 226         # If :tc=...: found then search this file again
 227         $entry =~ s/:tc=([^:]+):/:/ && ($tmp_term = $1, $state = 2);
 228         # protect any pattern metacharacters in $tmp_term
 229         $termpat = $tmp_term; $termpat =~ s/(\W)/\\$1/g;
 230     }
 231
 232     croak "Can't find $term" if $entry eq '';
 233     $entry =~ s/:+\s*:+/:/g;                            # cleanup $entry
 234     $entry =~ s/:+/:/g;                                 # cleanup $entry
 235     $self->{TERMCAP} = $entry;                          # save it
 236     # print STDERR "DEBUG: $entry = ", $entry, "\n";
 237
 238     # Precompile $entry into the object
 239     $entry =~ s/^[^:]*://;
 240     foreach $field (split(/:[\s:\\]*/,$entry)) {
 241         if ($field =~ /^(\w\w)$/) {
 242             $self->{'_' . $field} = 1 unless defined $self->{'_' . $1};
 243             # print STDERR "DEBUG: flag $1\n";
 244         }
 245         elsif ($field =~ /^(\w\w)\@/) {
 246             $self->{'_' . $1} = "";
 247             # print STDERR "DEBUG: unset $1\n";
 248         }
 249         elsif ($field =~ /^(\w\w)#(.*)/) {
 250             $self->{'_' . $1} = $2 unless defined $self->{'_' . $1};
 251             # print STDERR "DEBUG: numeric $1 = $2\n";
 252         }
 253         elsif ($field =~ /^(\w\w)=(.*)/) {
 254             # print STDERR "DEBUG: string $1 = $2\n";
 255             next if defined $self->{'_' . ($cap = $1)};
 256             $_ = $2;
 257             s/\\E/\033/g;
 258             s/\\(\d\d\d)/pack('c',oct($1) & 0177)/eg;
 259             s/\\n/\n/g;
 260             s/\\r/\r/g;
 261             s/\\t/\t/g;
 262             s/\\b/\b/g;
 263             s/\\f/\f/g;
 264             s/\\\^/\377/g;
 265             s/\^\?/\177/g;
 266             s/\^(.)/pack('c',ord($1) & 31)/eg;
 267             s/\\(.)/$1/g;
 268             s/\377/^/g;
 269             $self->{'_' . $cap} = $_;
 270         }
 271         # else { carp "junk in $term ignored: $field"; }
 272     }
 273     $self->{'_pc'} = "\0" unless defined $self->{'_pc'};
 274     $self->{'_bc'} = "\b" unless defined $self->{'_bc'};
 275     $self;
 276 }
 277
 278 # $terminal->Tpad($string, $cnt, $FH);
 279 sub Tpad { ## public
 280     my $self = shift;
 281     my($string, $cnt, $FH) = @_;
 282     my($decr, $ms);
 283
 284     if ($string =~ /(^[\d.]+)(\*?)(.*)$/) {
 285         $ms = $1;
 286         $ms *= $cnt if $2;
 287         $string = $3;
 288         $decr = $self->{PADDING};
 289         if ($decr > .1) {
 290             $ms += $decr / 2;
 291             $string .= $self->{'_pc'} x ($ms / $decr);
 292         }
 293     }
 294     print $FH $string if $FH;
 295     $string;
 296 }
 297
 298 # $terminal->Tputs($cap, $cnt, $FH);
 299 sub Tputs { ## public
 300     my $self = shift;
 301     my($cap, $cnt, $FH) = @_;
 302     my $string;
 303
 304     if ($cnt > 1) {
 305         $string = Tpad($self, $self->{'_' . $cap}, $cnt);
 306     } else {
 307         # cache result because Tpad can be slow
 308         $string = defined $self->{$cap} ? $self->{$cap} :
 309             ($self->{$cap} = Tpad($self, $self->{'_' . $cap}, 1));
 310     }
 311     print $FH $string if $FH;
 312     $string;
 313 }
 314
 315 # %%   output `%'
 316 # %d   output value as in printf %d
 317 # %2   output value as in printf %2d
 318 # %3   output value as in printf %3d
 319 # %.   output value as in printf %c
 320 # %+x  add x to value, then do %.
 321 #
 322 # %>xy if value > x then add y, no output
 323 # %r   reverse order of two parameters, no output
 324 # %i   increment by one, no output
 325 # %B   BCD (16*(value/10)) + (value%10), no output
 326 #
 327 # %n   exclusive-or all parameters with 0140 (Datamedia 2500)
 328 # %D   Reverse coding (value - 2*(value%16)), no output (Delta Data)
 329 #
 330 # $terminal->Tgoto($cap, $col, $row, $FH);
 331 sub Tgoto { ## public
 332     my $self = shift;
 333     my($cap, $code, $tmp, $FH) = @_;
 334     my $string = $self->{'_' . $cap};
 335     my $result = '';
 336     my $after = '';
 337     my $online = 0;
 338     my @tmp = ($tmp,$code);
 339     my $cnt = $code;
 340
 341     while ($string =~ /^([^%]*)%(.)(.*)/) {
 342         $result .= $1;
 343         $code = $2;
 344         $string = $3;
 345         if ($code eq 'd') {
 346             $result .= sprintf("%d",shift(@tmp));
 347         }
 348         elsif ($code eq '.') {
 349             $tmp = shift(@tmp);
 350             if ($tmp == 0 || $tmp == 4 || $tmp == 10) {
 351                 if ($online) {
 352                     ++$tmp, $after .= $self->{'_up'} if $self->{'_up'};
 353                 }
 354                 else {
 355                     ++$tmp, $after .= $self->{'_bc'};
 356                 }
 357             }
 358             $result .= sprintf("%c",$tmp);
 359             $online = !$online;
 360         }
 361         elsif ($code eq '+') {
 362             $result .= sprintf("%c",shift(@tmp)+ord($string));
 363             $string = substr($string,1,99);
 364             $online = !$online;
 365         }
 366         elsif ($code eq 'r') {
 367             ($code,$tmp) = @tmp;
 368             @tmp = ($tmp,$code);
 369             $online = !$online;
 370         }
 371         elsif ($code eq '>') {
 372             ($code,$tmp,$string) = unpack("CCa99",$string);
 373             if ($tmp[$[] > $code) {
 374                 $tmp[$[] += $tmp;
 375             }
 376         }
 377         elsif ($code eq '2') {
 378             $result .= sprintf("%02d",shift(@tmp));
 379             $online = !$online;
 380         }
 381         elsif ($code eq '3') {
 382             $result .= sprintf("%03d",shift(@tmp));
 383             $online = !$online;
 384         }
 385         elsif ($code eq 'i') {
 386             ($code,$tmp) = @tmp;
 387             @tmp = ($code+1,$tmp+1);
 388         }
 389         else {
 390             return "OOPS";
 391         }
 392     }
 393     $string = Tpad($self, $result . $string . $after, $cnt);
 394     print $FH $string if $FH;
 395     $string;
 396 }
 397
 398 # $terminal->Trequire(qw/ce ku kd/);
 399 sub Trequire { ## public
 400     my $self = shift;
 401     my($cap,@undefined);
 402     foreach $cap (@_) {
 403         push(@undefined, $cap)
 404             unless defined $self->{'_' . $cap} && $self->{'_' . $cap};
 405     }
 406     croak "Terminal does not support: (@undefined)" if @undefined;
 407 }
 408
 409 1;
 410