/etc/hosts php command

hosts_editor.php

#!/usr/bin/php
<?php

namespace ecoreng;

class HostsEditor
{
    // linux [run as root]
    protected $hosts = '/etc/hosts';
    
    // windows [run as administrator]
    //protected $hosts = 'C:\Windows\System32\Drivers\etc\hosts';
    
    protected $hostsEntries = [];

    protected function prompt($q, $default = '', $options = [], $max = 128, $forceOptions = true)
    {

        if (count($options) > 0) {
            $optionsStr = ' (' . implode(', ', $options) . ")";
        } else {
            $optionsStr = '';
        }
        echo $q . $optionsStr . ' [' . $default . ']: ';
        $fr = fopen("php://stdin", "r");
        $input = fgets($fr, $max);
        $input = rtrim($input);
        fclose($fr);
        echo PHP_EOL;

        if (count($options) > 0 && $default !== '' && $forceOptions) {
            if (!in_array($input, $options)) {
                $input = $default;
            }
        }

        if ($forceOptions && $input === '') {
            $input = $default;
        }

        return $input;
    }

    protected function pad($amount = 2)
    {
        echo str_repeat(PHP_EOL, $amount);
    }

    protected function heading($title, $char = '#')
    {
        echo str_repeat($char, 30) . PHP_EOL;
        echo ' ' . PHP_EOL;
        echo ' ' . $title . PHP_EOL;
        echo ' ' . PHP_EOL;
        echo str_repeat($char, 30) . PHP_EOL;
    }

    protected function checkPermissions()
    {
        $hosts = file_get_contents($this->hosts);
        $works = @file_put_contents($this->hosts, $hosts);
        if (!$works) {
            $this->heading('Not enough permissions to edit ' . $this->hosts, 'X');
            die();
        }

        // create a backup of the current file
        // as /etc/hosts~
        file_put_contents($this->hosts . '~', $hosts);
    }

    public function __construct()
    {
        $this->checkPermissions();
        $this->pad(1);
        $this->hostsEntries = file($this->hosts);
        $this->heading('HOST FILE EDITOR');
        $this->pad(1);
        $this->mainScreen();
    }

    public function mainScreen()
    {
        $i = 1;
        foreach ($this->hostsEntries as $host) {
            $f = substr($host, 0, 1);
            if ($f === PHP_EOL) {
                continue;
            }
            
            $needles = ['#[ ]+#', '#' . PHP_EOL . '#'];
            $replace = [chr(9), ''];
            
            if (substr($host, 0, 1) == '#') {
                $needles = ['#' . PHP_EOL . '#'];
                $replace = [''];
            }
            $this->hostsEntries[$i - 1] = $host = preg_replace($needles, $replace, $host);
            $il = str_pad($i, 2, 0, STR_PAD_LEFT);
            echo "[$il] " . $host . PHP_EOL;
            $i++;
        }
        $this->pad(1);


        $answer = strtolower($this->prompt('Action?', 'exit', ['{n}ew', '{e}dit', '{d}isable', 'en{a}ble', 'de{l}ete', '{s}ave',
                    'e{x}it'], 10, false));

        switch ($answer) {
            case 'edit':
            case 'e':
                $this->handleEdit();
                break;
            case 'new':
            case 'n':
                $this->handleNew();
                break;
            case 'disable':
            case 'd':
                $this->handleDisable();
                break;
            case 'delete':
            case 'l':
                $this->handleDelete();
                break;
            default:
            case 'exit':
            case 'x':
                break;
            case 'save':
            case 's':
                $this->handleSave();
                break;
            case 'enable':
            case 'a':
                $this->handleEnable();
                break;
        }
    }

    protected function handleEdit()
    {
        $options = ['0 = cancel'];
        $i = 1;
        foreach ($this->hostsEntries as $option) {
            $options[] = $i;
            $i++;
        }
        $entryIndex = (int) $this->prompt('Edit host entry number', '0', $options);
        if ($entryIndex === 0) {
            $this->pad();
            $this->mainScreen();
            return;
        }
        $entry = $this->hostsEntries[$entryIndex - 1];
        if (!$this->isDisabled($entry)) {
            $entry = explode(chr(9), $entry);

            $default = reset($entry);
            $ip = str_replace('$1', $default, $this->prompt('Edit Ip:', $default));

            $default = implode(' ', array_slice($entry, 1));
            $hosts = str_replace('$1', $default, $this->prompt('Edit Hosts:', $default));

            $newEntry = $ip . chr(9) . $hosts;
            $this->hostsEntries[$entryIndex - 1] = $newEntry;
            $this->heading('Host(s) edited: ' . PHP_EOL . ' ' . $newEntry, '=');
        } else {
            $this->heading('Host(s) is disabled or a comment', 'X');
        }
        $this->pad();
        $this->mainScreen();
    }

    protected function handleSave()
    {
        file_put_contents($this->hosts, implode(PHP_EOL, $this->hostsEntries));
    }

    protected function handleNew()
    {
        $newIp = $this->prompt('New IP:', '127.0.0.1');
        $newHosts = $this->prompt('Hosts:');
        $entry = $this->hostsEntries[] = $newIp . chr(9) . $newHosts;
        $this->heading('Host(s) added:' . PHP_EOL . ' ' . $entry, '=');
        $this->pad();
        $this->mainScreen();
    }

    protected function handleDisable()
    {
        $options = ['0 = cancel'];
        $i = 1;
        foreach ($this->hostsEntries as $option) {
            $options[] = $i;
            $i++;
        }
        $entryIndex = (int) $this->prompt('Disable host entry number', '0', $options);
        if ($entryIndex === 0) {
            $this->pad();
            $this->mainScreen();
            return;
        }
        $entry = $this->hostsEntries[$entryIndex - 1];
        if (!$this->isDisabled($entry)) {
            $this->hostsEntries[$entryIndex - 1] = '# ' . $entry;
            $this->heading('Host(s) disabled:' . PHP_EOL . ' ' . $entry, '=');
        } else {
            $this->heading('Host(s) is already disabled or a comment', 'X');
        }
        $this->pad();
        $this->mainScreen();
    }

    protected function isDisabled($entry)
    {
        return substr($entry, 0, 1) === '#';
    }

    protected function handleEnable()
    {
        $options = ['0 = cancel'];
        $i = 1;
        foreach ($this->hostsEntries as $option) {
            $options[] = $i;
            $i++;
        }
        $entryIndex = (int) $this->prompt('Enable host entry number', '0', $options);
        if ($entryIndex === 0) {
            $this->pad();
            $this->mainScreen();
            return;
        }
        $entry = $this->hostsEntries[$entryIndex - 1];
        if ($this->isDisabled($entry)) {
            $this->hostsEntries[$entryIndex - 1] = trim(substr($entry, 1));
            $this->heading('Host(s) enabled:' . PHP_EOL . ' ' . $entry, '=');
        } else {
            $this->heading('Host(s) not disabled:' . PHP_EOL . ' ' . $entry, 'X');
        }
        $this->pad();
        $this->mainScreen();
    }

    protected function handleDelete()
    {
        $options = ['0 = cancel'];
        $i = 1;
        foreach ($this->hostsEntries as $option) {
            $options[] = $i;
            $i++;
        }
        $entryIndex = (int) $this->prompt('Enable host entry number', '0', $options);
        if ($entryIndex === 0) {
            $this->pad();
            $this->mainScreen();
            return;
        }
        $entry = $this->hostsEntries[$entryIndex - 1];
        if (!$this->isDisabled($entry)) {

            $confirm = $this->prompt('Are you sure you want to delete "' . $entry . '"?', 'n', ['y', 'n'], 10);
            if ($confirm === 'y') {
                unset($this->hostsEntries[$entryIndex - 1]);
                $this->heading('Host(s) deleted:' . PHP_EOL . ' ' . $entry, '=');
                $this->pad();
                $this->mainScreen();
            }
        } else {
            $this->heading('Host(s) disabled', 'X');
        }
    }

}

$he = new \ecoreng\HostsEditor();