adding regex capabilities on simple cgi search - regex

I have this simple cgi script working just fine but I want to add regex capabilities. is that possible? if so what I need to add. thanks.
#!/usr/local/bin/perl
read(STDIN, $buffer,$ENV{'CONTENT_LENGTH'});
#pairs = split(/&/, $buffer);
foreach $pair (#pairs) {
($key, $value) = split(/=/, $pair);
foreach $pair (#pairs) {
($key, $value) = split(/=/, $pair);
$value =~ tr/+/ /;
$value =~ s/%([a-zA-Z0-9][a-zA-Z0-9])/pack("C", hex($1))/eg;
$formdata{$key}.= "$value";
}
}
$search = $formdata{'search'};
open(INFO, "/test/myfile");
#array=<INFO>;
close (INFO);
...code truncate

To find lines that end with ".cgi":
my #array = grep /\.cgi$/, <INFO>;

Related

match using regex in perl

HI I am trying to exract some data from a text file in perl. My file looks like this
Name:John
FirstName:Smith
Name:Alice
FirstName:Meyers
....
I want my string to look like John Smith and Alice Meyers
I tried something like this but I'm stuck and I don't know how to continue
while (<INPUT>) {
if (/^[Name]/) {
$match =~ /(:)(.*?)(\n) /
$string = $string.$2;
}
if (/^[FirstName]/) {
$match =~ /(:)(.*?)(\n)/
$string = $string.$2;
}
}
What I try to do is that when I match Name or FirstName to copy to content between : and \n but I get confused which is $1 and $2
This will put you first and last names in a hash:
use strict;
use warnings;
use Data::Dumper;
open my $in, '<', 'in.txt';
my (%data, $names, $firstname);
while(<$in>){
chomp;
($names) = /Name:(.*)/ if /^Name/;
($firstname) = /FirstName:(.*)/ if /^FirstName/;
$data{$names} = $firstname;
}
print Dumper \%data;
Through perl one-liner,
$ perl -0777 -pe 's/(?m).*?Name:([^\n]*)\nFirstName:([^\n]*).*/\1 \2/g' file
John Smith
Alice Meyers
while (<INPUT>) {
/^([A-Za-z])+\:\s*(.*)$/;
if ($1 eq 'Name') {
$surname = $2;
} elsif ($1 eq 'FirstName') {
$completeName = $2 . " " . $surname;
} else {
/* Error */
}
}
You might want to add some error handling, e.g. make sure that a Name is always followed by a FirstName and so on.
$1 $2 $3 .. $N , it's the capture result of () inside regex.
If you do something like that , you cant avoid using $1 like variables.
my ($matched1,$matched2) = $text =~ /(.*):(.*)/
my $names = [];
my $name = '';
while(my $row = <>){
$row =~ /:(.*)/;
$name = $name.' '.$1;
push(#$names,$name) if $name =~ / /;
$name = '' if $name =~ / /;
}
`while(<>){
}
`
open (FH,'abc.txt');
my(%hash,#array);
map{$_=~s/.*?://g;chomp($_);push(#array,$_)} <FH>;
%hash=#array;
print Dumper \%hash;

Looking for an elegant way to search for many file extensions into a filename string

I would like to find out if a file has a particular file extension, selected in a list of extensions.
I had this initial idea:
my $file = "filename.zip";
my #allowedExts = ( '.zip', '.tar.gz', '.tar.bz2' );
my $found = 0;
foreach $ext (#allowedExts) {
if (index($file, $ext) != -1) {
$found = 1;
last;
}
}
print "found" if ($found);
Is there a simpler way to do that?
If you truly have many extensions (not just three), avoid the loop by finding the extension first, then checking a hash:
my $file = "filename.zip";
my #allowedExts = ( '.zip', '.tar.gz', '.tar.bz2' );
my %allowedExts;
#allowedExts{#allowedExts} = ();
my (undef, $ext) = split /(?=\.)/, $file, 2;
my $found = $ext && exists $allowedExts{$ext};
The above will treat everything in the filename starting from the first .; if you have . in the filename before what you want to find as an extension, you can assemble all the extensions into a single regex:
my $file = "filename.zip";
my #allowedExts = ( '.zip', '.tar.gz', '.tar.bz2' );
my $found = $filename =~ ( join( '|', map quotemeta, #allowedExts ) . '\z' );
index is not a good idea here, you might get very unexpected behaviour if the extension itself is found somewhere in the middle of filename.
Also: ALWAYS use strict and use warnings
Regex matching at the end of the string will be a better solution here, see the code below.
$ is a metacharacter used to match the end of the line (or before newline at the end)
#!/usr/bin/perl
use strict;
use warnings;
my $file = "filename.zip";
my #allowedExts = ( '.zip', '.tar.gz', '.tar.bz2' );
my $found = 0;
foreach my $ext (#allowedExts) {
if ($file =~ /\Q$ext\E$/) {
$found = 1;
last;
}
}
print "found" if ($found);
You will probably get loads of other ideas for solving this. As always with perl: TIMTOWTDI.
EDIT:
As #ikegami suggested, regex should be escaped so that the dot is not treated as metacharacter but literal match, \Q and \E escape metacharacters in the regex.
use List::Util qw(first);
my $file = "filename.zip";
my #allowedExts = map qr/\Q$_$/, ( '.zip', '.tar.gz', '.tar.bz2' );
my $found = first { $file =~ /$_/ } #allowedExts;
Anther approach is to use regular expressions.
Build the regex:
my #allowedExts = qw( .zip .tar.gz .tar.bz2 );
my $pat = join '|', map quotemeta, #allowedExts;
my $re = qr/$pat\z/;
Use it:
my $file = "filename.zip";
print "Found\n" if $file =~ $re;

Find text enclosed by # and replace the inside

The problem:
Find pieces of text in a file enclosed by # and replace the inside
Input:
#abc# abc #ABC#
cba #cba CBA#
Deisred output:
абц abc АБЦ
cba цба ЦБА
I have the following:
#!/usr/bin/perl
use strict;
use warnings;
use Encode;
my $output;
open FILE,"<", 'test.txt';
while (<FILE>) {
chomp(my #chars = split(//, $_));
for (#chars) {
my #char;
$_ =~ s/a/chr(0x430)/eg;
$_ =~ s/b/chr(0x431)/eg;
$_ =~ s/c/chr(0x446)/eg;
$_ =~ s/d/chr(0x434)/eg;
$_ =~ s/e/chr(0x435)/eg;
$_ =~ s/A/chr(0x410)/eg;
$_ =~ s/B/chr(0x411)/eg;
$_ =~ s/C/chr(0x426)/eg;
push #char, $_;
$output = join "", #char;
print encode("utf-8",$output);}
print "\n";
}
close FILE;
But I'm stuck on how to process further
Thanks for help in advance!
Kluther
Here my solution. (you will fixed it, yes. It is prototype)
for (my $data = <DATA>){
$data=~s/[#]([\s\w]+)[#]/func($1)/ge;
print $data;
# while($data=~m/[#]([\s\w]+)[#]/g){
# print "marked: ",$1,"\n";
# print "position:", pos();
# }
# print "not marked: ";
}
sub func{
#do your magic here ;)
return "<< #_ >>";
}
__DATA__
#abc# abc #ABC# cba #cba CBA#
What happens here?
First, I read data. You can do it yourself.
for (my $data = <DATA>){...}
Next, I need to search your pattern and replace it.
What should I do?
Use substition operator: s/pattern/replace/
But in interesting form:
s/pattern/func($1)/ge
Key g mean Global Search
Key e mean Evaluate
So, I think, that you need to write your own func function ;)
Maybe better to use transliteration operator: tr/listOfSymbolsToBeReplaced/listOfSymbolsThatBePlacedInstead/
With minimal changes to your algorithm you need to keep track of whether you are inside the #marks or not. so add something like this
my $bConvert = 0;
chomp(my #chars = split(//, $_));
for (#chars) {
my $char = $_;
if (/#/) {
$bConvert = ($bConvert + 1) % 2;
next;
}
elsif ($bConvert) {
$char =~ s/a/chr(0x430)/eg;
$char =~ s/b/chr(0x431)/eg;
$char =~ s/c/chr(0x446)/eg;
$char =~ s/d/chr(0x434)/eg;
$char =~ s/e/chr(0x435)/eg;
$char =~ s/A/chr(0x410)/eg;
$char =~ s/B/chr(0x411)/eg;
$char =~ s/C/chr(0x426)/eg;
}
print encode("utf-8",$char);
}
Try this after $output is processed.
$output =~ s/\#//g;
my #split_output = split(//, $output);
$output = "";
my $len = scalar(#split_output) ;
while ($len--) {
$output .= shift(#split_output);
}
print $output;
It can be done with a single regex and no splitting of the string:
use strict;
use warnings;
use Encode;
my %chars = (
a => chr(0x430),
b => chr(0x431),
c => chr(0x446),
d => chr(0x434),
e => chr(0x435),
A => chr(0x410),
B => chr(0x411),
C => chr(0x426),
);
my $regex = '(' . join ('|', keys %chars) . ')';
while (<DATA>) {
1 while ($_ =~ s|\#(?!\s)[^#]*?\K$regex(?=[^#]*(?!\s)\#)|$chars{$1}|eg);
print encode("utf-8",$_);
}
It does require repeated runs of the regex due to the overlapping nature of the matches.

Perl Regular Expression to insert/substitute in a string at specific places

Given a url the following regular expression is able insert/substitute in words at certain points in the urls.
Code:
#!/usr/bin/perl
use strict;
use warnings;
#use diagnostics;
my #insert_words = qw/HELLO GOODBYE/;
my $word = 0;
my $match;
while (<DATA>) {
chomp;
foreach my $word (#insert_words)
{
my $repeat = 1;
while ((my $match=$_) =~ s|(?<![/])(?:[/](?![/])[^/]*){$repeat}[^/]*\K|$word|)
{
print "$match\n";
$repeat++;
}
print "\n";
}
}
__DATA__
http://www.stackoverflow.com/dog/cat/rabbit/
http://www.superuser.co.uk/dog/cat/rabbit/hamster/
10.15.16.17/dog/cat/rabbit/
The output given (for the first example url in __DATA__ with the HELLO word):
http://www.stackoverflow.com/dogHELLO/cat/rabbit/
http://www.stackoverflow.com/dog/catHELLO/rabbit/
http://www.stackoverflow.com/dog/cat/rabbitHELLO/
http://www.stackoverflow.com/dog/cat/rabbit/HELLO
Where I am now stuck:
I would now like to alter the regular expression so that the output will look like what is shown below:
http://www.stackoverflow.com/dogHELLO/cat/rabbit/
http://www.stackoverflow.com/dog/catHELLO/rabbit/
http://www.stackoverflow.com/dog/cat/rabbitHELLO/
http://www.stackoverflow.com/dog/cat/rabbit/HELLO
#above is what it already does at the moment
#below is what i also want it to be able to do as well
http://www.stackoverflow.com/HELLOdog/cat/rabbit/ #<-puts the word at the start of the string
http://www.stackoverflow.com/dog/HELLOcat/rabbit/
http://www.stackoverflow.com/dog/cat/HELLOrabbit/
http://www.stackoverflow.com/dog/cat/rabbit/HELLO
http://www.stackoverflow.com/HELLO/cat/rabbit/ #<- now also replaces the string with the word
http://www.stackoverflow.com/dog/HELLO/rabbit/
http://www.stackoverflow.com/dog/cat/HELLO/
http://www.stackoverflow.com/dog/cat/rabbit/HELLO
But I am having trouble getting it to automatically do this within the one regular expression.
Any help with this matter would be highly appreciated, many thanks
One solution:
use strict;
use warnings;
use URI qw( );
my #insert_words = qw( HELLO );
while (<DATA>) {
chomp;
my $url = URI->new($_);
my $path = $url->path();
for (#insert_words) {
# Use package vars to communicate with /(?{})/ blocks.
local our $insert_word = $_;
local our #paths;
$path =~ m{
^(.*/)([^/]*)((?:/.*)?)\z
(?{
push #paths, "$1$insert_word$2$3";
if (length($2)) {
push #paths, "$1$insert_word$3";
push #paths, "$1$2$insert_word$3";
}
})
(?!)
}x;
for (#paths) {
$url->path($_);
print "$url\n";
}
}
}
__DATA__
http://www.stackoverflow.com/dog/cat/rabbit/
http://www.superuser.co.uk/dog/cat/rabbit/hamster/
http://10.15.16.17/dog/cat/rabbit/
Without crazy regexes:
use strict;
use warnings;
use URI qw( );
my #insert_words = qw( HELLO );
while (<DATA>) {
chomp;
my $url = URI->new($_);
my $path = $url->path();
for my $insert_word (#insert_words) {
my #parts = $path =~ m{/([^/]*)}g;
my #paths;
for my $part_idx (0..$#parts) {
my $orig_part = $parts[$part_idx];
local $parts[$part_idx];
{
$parts[$part_idx] = $insert_word . $orig_part;
push #paths, join '', map "/$_", #parts;
}
if (length($orig_part)) {
{
$parts[$part_idx] = $insert_word;
push #paths, join '', map "/$_", #parts;
}
{
$parts[$part_idx] = $orig_part . $insert_word;
push #paths, join '', map "/$_", #parts;
}
}
}
for (#paths) {
$url->path($_);
print "$url\n";
}
}
}
__DATA__
http://www.stackoverflow.com/dog/cat/rabbit/
http://www.superuser.co.uk/dog/cat/rabbit/hamster/
http://10.15.16.17/dog/cat/rabbit/
one more solution:
#!/usr/bin/perl
use strict;
use warnings;
my #insert_words = qw/HELLO GOODBYE/;
while (<DATA>) {
chomp;
/(?<![\/])(?:[\/](?![\/])[^\/]*)/p;
my $begin_part = ${^PREMATCH};
my $tail = ${^MATCH} . ${^POSTMATCH};
my #tail_chunks = split /\//, $tail;
foreach my $word (#insert_words) {
for my $index (1..$#tail_chunks) {
my #new_tail = #tail_chunks;
$new_tail[$index] = $word . $tail_chunks[$index];
my $str = $begin_part . join "/", #new_tail;
print $str, "\n";
$new_tail[$index] = $tail_chunks[$index] . $word;
$str = $begin_part . join "/", #new_tail;
print $str, "\n";
}
print "\n";
}
}
__DATA__
http://www.stackoverflow.com/dog/cat/rabbit/
http://www.superuser.co.uk/dog/cat/rabbit/hamster/
10.15.16.17/dog/cat/rabbit/

Match different variant of a word using regex Perl

I am splitting sentences at individual space characters, and then matching these terms against keys of hashes. I am getting matches only if the terms are 100% similar, and I am struggling to find a perfect regex that could match several occurrences of the same word. Eg. Let us consider I have a term 'antagon' now it perfectly matches with the term 'antagon' but fails to match with antagonists, antagonistic or pre-antagonistic, hydro-antagonist etc. Also I need a regex to match occurrences of words like MCF-7 with MCF7 or MC-F7 silencing the effect of special characters and so on.
This is the code that I have till now; thr commented part is where I am struggling.
(Note: Terms in the hash are stemmed to root form of a word).
use warnings;
use strict;
use Drug;
use Stop;
open IN, "sample.txt" or die "cannot find sample";
open OUT, ">sample1.txt" or die "cannot find sample";
while (<IN>) {
chomp $_;
my $flag = 0;
my $line = lc $_;
my #full = ();
if ( $line =~ /<Sentence.*>(.*)<\/Sentence>/i ) {
my $string = $1;
chomp $string;
$string =~ s/,/ , /g;
$string =~ s/\./ \. /g;
$string =~ s/;/ ; /g;
$string =~ s/\(/ ( /g;
$string =~ s/\)/ )/g;
$string =~ s/\:/ : /g;
$string =~ s/\::/ :: )/g;
my #array = split / /, $string;
foreach my $word (#array) {
chomp $word;
if ( $word =~ /\,|\;|\.|\(|\)/g ) {
push( #full, $word );
}
if ( $Stop_words{$word} ) {
push( #full, $word );
}
if ( $Values{$word} ) {
my $term = "<Drug>$word<\/Drug>";
push( #full, $term );
}
else {
push( #full, $word );
}
# if($word=~/.*\Q$Values{$word}\E/i)#Changed this
# {
# $term="<Drug>$word</$Drug>";
# print $term,"\n";
# push(#full,$term);
# }
}
}
my $mod_str = join( " ", #full );
print OUT $mod_str, "\n";
}
I need a regex to match occurances of words like MCF-7 with MCF7 or
MC-F7
The most straightforward approach is just to strip out the hyphenss i.e.
my $ignore_these = "[-_']"
$word =~ s{$ignore_these}{}g;
I am not sure what is stored in your Value hash, so its hard to tell what you expect to happen
if($word=~/.*\Q$Values{$word}\E/i)
However, the kind of thing I imagin you want is (simplified your code somewhat)
#!/usr/bin/perl
use strict;
use warnings;
use utf8;
use 5.10.0;
use Data::Dumper;
while (<>) {
chomp $_;
my $flag = 0;
my $line = lc $_;
my #full = ();
if ( $line =~ /<Sentence.*>(.*)<\/Sentence>/i ) {
my $string = $1;
chomp $string;
$string =~ s/([,\.;\(\)\:])/ $1 /g; # squished these together
$string =~ s/\:\:/ :: )/g; # typo in original
my #array = split /\s+/, $string; # split on one /or more/ spaces
foreach my $word (#array) {
chomp $word;
my $term=$word;
my $word_chars = "[\\w\\-_']";
my $word_part = "antagon";
if ($word =~ m{$word_chars*?$word_part$word_chars+}) {
$term="<Drug>$word</Drug>";
}
push(#full,$term); # push
}
}
my $mod_str = join( " ", #full );
say "<Sentence>$mod_str</Sentence>";
}
This gives me the following output, which is my best guess at what you expect:
$ cat tmp.txt
<Sentence>This in antagonizing the antagonist's antagonism pre-antagonistically.</Sentence>
$ cat tmp.txt | perl x.pl
<Sentence>this in <Drug>antagonizing</Drug> the <Drug>antagonist's</Drug> <Drug>antagonism</Drug> <Drug>pre-antagonistically</Drug> .</Sentence>
$
perl -ne '$things{$1}++while s/([^ ;.,!?]*?antagon[^ ;.,!?]++)//;END{print "$_\n" for sort keys %things}' FILENAME
If the file contains the following:
he was an antagonist
antagonize is a verb
why are you antagonizing her?
this is an alpha-antagonist
This will return:
alpha-antagonist
antagonist
antagonize
antagonizing
Below is the a regular (not one-liner) version:
#!/usr/bin/perl
use warnings;
use strict;
open my $in, "<", "sample.txt" or die "could not open sample.txt for reading!";
open my $out, ">", "sample1.txt" or die "could not open sample1.txt for writing!";
my %things;
while (<$in>){
$things{$1}++ while s/([^ ;.,!?]*?antagon[^ ;.,!?]++)//
}
print $out "$_\n" for sort keys %things;
You may want to take another look at your assumptions on your approach. What it sounds like to me is that you are looking for words which are within a certain distance of a list of words. Take a look at the Levenshtein distance formula to see if this is something you want. Be aware, however, that computing this might take exponential time.