MySQL, PostgreSQL: Fix queries splitting and string constants

Thanks to alxivnov (https://github.com/vrana/adminer/pull/490).

adminer/drivers/mssql.inc.php

@@ -637,6 +637,10 @@ WHERE sys1.xtype = 'TR' AND sys2.name = " . q($table)
 		return false;
 	}
 
+	function is_c_style_escapes() {
+		return true;
+	}
+
 	function show_status() {
 		return array();
 	}

adminer/drivers/mysql.inc.php

@@ -1074,6 +1074,16 @@ if (!defined("DRIVER")) {
 		return $strictMode;
 	}
 
+	function is_c_style_escapes() {
+		static $c_style = null;
+
+		if ($c_style === null) {
+			$c_style = strpos(get_key_vals("SHOW VARIABLES LIKE 'sql_mode'")["sql_mode"], 'NO_BACKSLASH_ESCAPES') === false;
+		}
+
+		return $c_style;
+	}
+
 	/** Get process list
 	* @return array ($row)
 	*/

adminer/drivers/oracle.inc.php

@@ -493,6 +493,10 @@ AND c_src.TABLE_NAME = " . q($table);
 		return false;
 	}
 
+	function is_c_style_escapes() {
+		return true;
+	}
+
 	function process_list() {
 		return get_rows('SELECT sess.process AS "process", sess.username AS "user", sess.schemaname AS "schema", sess.status AS "status", sess.wait_class AS "wait_class", sess.seconds_in_wait AS "seconds_in_wait", sql.sql_text AS "sql_text", sess.machine AS "machine", sess.port AS "port"
 FROM v$session sess LEFT OUTER JOIN v$sql sql

adminer/drivers/pgsql.inc.php

@@ -885,6 +885,16 @@ AND typelem = 0"
 		return false;
 	}
 
+	function is_c_style_escapes() {
+		static $c_style = null;
+
+		if ($c_style === null) {
+			$c_style = get_vals("SHOW standard_conforming_strings")[0] == "off";
+		}
+
+		return $c_style;
+	}
+
 	function process_list() {
 		return get_rows("SELECT * FROM pg_stat_activity ORDER BY " . (min_version(9.2) ? "pid" : "procpid"));
 	}
@@ -949,6 +959,7 @@ AND typelem = 0"
 					"char|text" => "||",
 				)
 			),
+			'c_style_escapes' => true,
 		);
 	}
 }

adminer/drivers/sqlite.inc.php

@@ -771,6 +771,10 @@ if (isset($_GET["sqlite"]) || isset($_GET["sqlite2"])) {
 		return false;
 	}
 
+	function is_c_style_escapes() {
+		return true;
+	}
+
 	function show_status() {
 		$return = array();
 		foreach (get_vals("PRAGMA compile_options") as $option) {

adminer/sql.inc.php

@@ -81,7 +81,21 @@ if (!$error && $_POST) {
 					$offset = $pos + strlen($found);
 
 					if ($found && rtrim($found) != $delimiter) { // find matching quote or comment end
-						while (preg_match('(' . ($found == '/*' ? '\*/' : ($found == '[' ? ']' : (preg_match('~^-- |^#~', $found) ? "\n" : preg_quote($found) . "|\\\\."))) . '|$)s', $query, $match, PREG_OFFSET_CAPTURE, $offset)) { //! respect sql_mode NO_BACKSLASH_ESCAPES
+						$c_style_escapes = is_c_style_escapes() || ($jush == "pgsql" && ($pos > 0 && strtolower($query[$pos - 1]) == "e"));
+
+						$pattern = '(';
+						if ($found == '/*') {
+							$pattern .= '\*/';
+						} elseif ($found == '[') {
+							$pattern .= ']';
+						} elseif (preg_match('~^-- |^#~', $found)) {
+							$pattern .= "\n";
+						} else {
+							$pattern .= preg_quote($found) . ($c_style_escapes ? "|\\\\." : "");
+						}
+						$pattern .= '|$)s';
+
+						while (preg_match($pattern, $query, $match, PREG_OFFSET_CAPTURE, $offset)) {
 							$s = $match[0][0];
 							if (!$s && $fp && !feof($fp)) {
 								$query .= fread($fp, 1e5);