Reading a file and extracting data using a regex in PHP - php

Question

I am trying to echo out the names/paths of the files that are written in logfile.txt. For that, I use a regex to match everything before the first ocurrence of : and output it. I am reading the logfile.txt line by line:
<?php
$logfile = fopen("logfile.txt", "r");
if ($logfile) {
while (($line = fgets($logfile)) !== false) {
if (preg_match_all("/[^:]*/", $line, $matched)) {
foreach ($matched as $val) {
foreach ($val as $read) {
echo '<pre>'. $read . '</pre>';
}
}
}
}
fclose($logfile);
} else {
die("Unable to open file.");
}
?>
However, I get the entire contents of the file instead. The desired output would be:
/home/user/public_html/an-ordinary-shell.php
/home/user/public_html/content/execution-after-redirect.html
/home/user/public_html/paypal-gateway.html
Here is the content of logfile.txt:
-------------------------------------------------------------------------------
/home/user/public_html/an-ordinary-shell.php: Php.Trojan.PCT4-1 FOUND
/home/user/public_html/content/execution-after-redirect.html: {LDB}VT-malware33.UNOFFICIAL FOUND
/home/user/public_html/paypal-gateway.html: Html.Exploit.CVE.2015_6073
Extra question: How do I skip reading the first two lines (namely the dashes and emtpy line)?

Answer 1

Here you go:
<?php
# load it as a string
$data = #file("logfile.txt");
# data for this specific purpose
$data = <<< DATA
-------------------------------------------------------------------------------
/home/user/public_html/an-ordinary-shell.php: Php.Trojan.PCT4-1 FOUND
/home/user/public_html/content/execution-after-redirect.html: {LDB}VT-malware33.UNOFFICIAL FOUND
/home/user/public_html/paypal-gateway.html: Html.Exploit.CVE.2015_6073
DATA;
$regex = '~^(/[^:]+):~m';
# ^ - anchor it to the beginning
# / - a slash
# ([^:]+) capture at least anything NOT a colon
# turn on multiline mode with m
preg_match_all($regex, $data, $files);
print_r($files);
?>
It even skips both your lines, see a demo on ideone.com.

Answer 2

preg_match_all returns all occurrences for the pattern. For the first line, it will return:
/home/user/public_html/an-ordinary-shell.php,an empty string, Php.Trojan.PCT4-1 FOUND
and an other empty string
that don't contain :.
to obtain a single result, use preg_match, but to do that using explode should suffice.
To skip lines you don't want, you can for example build a generator function that gives only the good lines. You can also use a stream filter.