add custom provider support

README.md

@@ -40,7 +40,7 @@ var_dump(
 
 ```
 var_dump(
-    \Yggverse\Net\Dig::records('yo.index', ['A', 'AAAA'])
+    \Yggverse\Net\Dig::records('yo.index', ['A', 'AAAA'], &$result = [], &$error = [], $provider = null)
 );
 ```
 

src/Dig.php

@@ -17,32 +17,59 @@ class Dig
         ];
     }
 
+    public static function isProvider(mixed $value): bool
+    {
+        return
+        (
+            is_string($value) &&
+            false !== filter_var($value, FILTER_VALIDATE_IP)
+        );
+    }
+
     public static function isHostName(mixed $value, array $find = ['_'], array $replace = []): bool
     {
-        return is_string($value) && false !== filter_var(str_replace($find, $replace, $value), FILTER_VALIDATE_DOMAIN, FILTER_FLAG_HOSTNAME);
+        return (
+            is_string($value) &&
+            false !== filter_var(str_replace($find, $replace, $value), FILTER_VALIDATE_DOMAIN, FILTER_FLAG_HOSTNAME)
+        );
     }
 
     public static function isRecord(mixed $value): bool
     {
-        return is_string($value) && isset(self::_records()[$value]);
+        return
+        (
+            is_string($value) &&
+            isset(self::_records()[$value])
+        );
     }
 
     public static function isRecordValue(mixed $record, mixed $value): bool
     {
-        return is_string($record) &&
+        return
-               is_string($value)  &&
+        (
-               isset(self::_records()[$record]) && self::_records()[$record]($value);
+            is_string($record) &&
+            is_string($value)  &&
+            isset(self::_records()[$record]) && self::_records()[$record]($value)
+        );
     }
 
-    public static function records(string $hostname, array $records, array &$result = [], array &$error = []): array
+    public static function records(string $hostname, array $records, array &$result = [], array &$error = [], ?string $provider = null): array
     {
+        if (self::isProvider($provider))
+        {
+            $provider = sprintf(
+                '@%s',
+                $provider
+            );
+        }
+
         if (self::isHostName($hostname))
         {
             foreach ($records as $record)
             {
                 if (self::isRecord($record))
                 {
-                    if ($values = exec(sprintf('dig %s %s +short', $record, $hostname)))
+                    if ($values = exec(sprintf('dig %s %s %s +short', (string) $provider, (string) $record, (string) $hostname)))
                     {
                         foreach (explode(PHP_EOL, $values) as $value)
                         {