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|
#! /usr/bin/perl
# Program for testing regular expressions with perl to check that PCRE handles
# them the same.
# Function for turning a string into a string of printing chars
sub pchars {
my($t) = "";
foreach $c (split(//, $_[0]))
{
if (ord $c >= 32 && ord $c < 127) { $t .= $c; }
else { $t .= sprintf("\\x%02x", ord $c); }
}
$t;
}
# Read lines from named file or stdin and write to named file or stdout; lines
# consist of a regular expression, in delimiters and optionally followed by
# options, followed by a set of test data, terminated by an empty line.
# Sort out the input and output files
if (@ARGV > 0)
{
open(INFILE, "<$ARGV[0]") || die "Failed to open $ARGV[0]\n";
$infile = "INFILE";
}
else { $infile = "STDIN"; }
if (@ARGV > 1)
{
open(OUTFILE, ">$ARGV[1]") || die "Failed to open $ARGV[1]\n";
$outfile = "OUTFILE";
}
else { $outfile = "STDOUT"; }
printf($outfile "Perl $] Regular Expressions\n\n");
# Main loop
NEXT_RE:
for (;;)
{
printf " re> " if $infile eq "STDIN";
last if ! ($_ = <$infile>);
printf $outfile "$_" if $infile ne "STDIN";
next if ($_ eq "");
$pattern = $_;
while ($pattern !~ /^\s*(.).*\1/s)
{
printf " > " if $infile eq "STDIN";
last if ! ($_ = <$infile>);
printf $outfile "$_" if $infile ne "STDIN";
$pattern .= $_;
}
chomp($pattern);
$pattern =~ s/\s+$//;
# The private /+ modifier means "print $' afterwards". We use it
# only on the end of patterns to make it easy to chop off here.
$showrest = ($pattern =~ s/\+(?=[a-z]*$)//);
# Check that the pattern is valid
eval "\$_ =~ ${pattern}";
if ($@)
{
printf $outfile "Error: $@";
next NEXT_RE;
}
# If the /g modifier is present, we want to put a loop round the matching;
# otherwise just a single "if".
$cmd = ($pattern =~ /g[a-z]*$/)? "while" : "if";
# If the pattern is actually the null string, Perl uses the most recently
# executed (and successfully compiled) regex is used instead. This is a
# nasty trap for the unwary! The PCRE test suite does contain null strings
# in places - if they are allowed through here all sorts of weird and
# unexpected effects happen. To avoid this, we replace such patterns with
# a non-null pattern that has the same effect.
$pattern = "/(?#)/$2" if ($pattern =~ /^(.)\1(.*)$/);
# Read data lines and test them
for (;;)
{
printf "data> " if $infile eq "STDIN";
last NEXT_RE if ! ($_ = <$infile>);
chomp;
printf $outfile "$_\n" if $infile ne "STDIN";
s/\s+$//;
s/^\s+//;
last if ($_ eq "");
$x = eval "\"$_\""; # To get escapes processed
# Empty array for holding results, then do the matching.
@subs = ();
eval "${cmd} (\$x =~ ${pattern}) {" .
"push \@subs,\$&;" .
"push \@subs,\$1;" .
"push \@subs,\$2;" .
"push \@subs,\$3;" .
"push \@subs,\$4;" .
"push \@subs,\$5;" .
"push \@subs,\$6;" .
"push \@subs,\$7;" .
"push \@subs,\$8;" .
"push \@subs,\$9;" .
"push \@subs,\$10;" .
"push \@subs,\$11;" .
"push \@subs,\$12;" .
"push \@subs,\$13;" .
"push \@subs,\$14;" .
"push \@subs,\$15;" .
"push \@subs,\$16;" .
"push \@subs,\$'; }";
if ($@)
{
printf $outfile "Error: $@\n";
next NEXT_RE;
}
elsif (scalar(@subs) == 0)
{
printf $outfile "No match\n";
}
else
{
while (scalar(@subs) != 0)
{
printf $outfile (" 0: %s\n", &pchars($subs[0]));
printf $outfile (" 0+ %s\n", &pchars($subs[17])) if $showrest;
$last_printed = 0;
for ($i = 1; $i <= 16; $i++)
{
if (defined $subs[$i])
{
while ($last_printed++ < $i-1)
{ printf $outfile ("%2d: <unset>\n", $last_printed); }
printf $outfile ("%2d: %s\n", $i, &pchars($subs[$i]));
$last_printed = $i;
}
}
splice(@subs, 0, 18);
}
}
}
}
printf $outfile "\n";
# End
|
