diff options
author | Jason Downs <downsj@cvs.openbsd.org> | 1996-08-19 10:13:38 +0000 |
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committer | Jason Downs <downsj@cvs.openbsd.org> | 1996-08-19 10:13:38 +0000 |
commit | 14856225739aa48b6c9cf4c17925362b2d95cea3 (patch) | |
tree | dfd38f1b654fb5bbdfc38887c1a829b658e71530 /gnu/usr.bin/perl/lib/Search | |
parent | 77469082517e44fe6ca347d9e8dc7dffd1583637 (diff) |
Import of Perl 5.003 into the tree. Makefile.bsd-wrapper and
config.sh.OpenBSD are the only local changes.
Diffstat (limited to 'gnu/usr.bin/perl/lib/Search')
-rw-r--r-- | gnu/usr.bin/perl/lib/Search/Dict.pm | 75 |
1 files changed, 75 insertions, 0 deletions
diff --git a/gnu/usr.bin/perl/lib/Search/Dict.pm b/gnu/usr.bin/perl/lib/Search/Dict.pm new file mode 100644 index 00000000000..295da6b31d2 --- /dev/null +++ b/gnu/usr.bin/perl/lib/Search/Dict.pm @@ -0,0 +1,75 @@ +package Search::Dict; +require 5.000; +require Exporter; + +@ISA = qw(Exporter); +@EXPORT = qw(look); + +=head1 NAME + +Search::Dict, look - search for key in dictionary file + +=head1 SYNOPSIS + + use Search::Dict; + look *FILEHANDLE, $key, $dict, $fold; + +=head1 DESCRIPTION + +Sets file position in FILEHANDLE to be first line greater than or equal +(stringwise) to I<$key>. Returns the new file position, or -1 if an error +occurs. + +The flags specify dictionary order and case folding: + +If I<$dict> is true, search by dictionary order (ignore anything but word +characters and whitespace). + +If I<$fold> is true, ignore case. + +=cut + +sub look { + local(*FH,$key,$dict,$fold) = @_; + local($_); + my(@stat) = stat(FH) + or return -1; + my($size, $blksize) = @stat[7,11]; + $blksize ||= 8192; + $key =~ s/[^\w\s]//g if $dict; + $key =~ tr/A-Z/a-z/ if $fold; + my($min, $max, $mid) = (0, int($size / $blksize)); + while ($max - $min > 1) { + $mid = int(($max + $min) / 2); + seek(FH, $mid * $blksize, 0) + or return -1; + <FH> if $mid; # probably a partial line + $_ = <FH>; + chop; + s/[^\w\s]//g if $dict; + tr/A-Z/a-z/ if $fold; + if (defined($_) && $_ lt $key) { + $min = $mid; + } + else { + $max = $mid; + } + } + $min *= $blksize; + seek(FH,$min,0) + or return -1; + <FH> if $min; + for (;;) { + $min = tell(FH); + $_ = <FH> + or last; + chop; + s/[^\w\s]//g if $dict; + y/A-Z/a-z/ if $fold; + last if $_ ge $key; + } + seek(FH,$min,0); + $min; +} + +1; |