From b64a94516b7c789fd36a7a2d4a7ecec10c3bfe17 Mon Sep 17 00:00:00 2001
From: Lars Knoll <lars.knoll@theqtcompany.com>
Date: Thu, 4 Feb 2016 23:07:26 +0100
Subject: [PATCH] Get rid of the QRegExp dependency in qxmlutils.

This makes the XML parser 100% independent of having regexp
support enabled.

Change-Id: I73004b0fb71e8086618995c71a985a86c292df3d
Reviewed-by: Robin Burchell <robin.burchell@viroteck.net>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
---
 src/corelib/xml/qxmlutils.cpp | 23 ++++++++++++++---------
 1 file changed, 14 insertions(+), 9 deletions(-)

diff --git a/src/corelib/xml/qxmlutils.cpp b/src/corelib/xml/qxmlutils.cpp
index 51c52cd3d0..23caae2935 100644
--- a/src/corelib/xml/qxmlutils.cpp
+++ b/src/corelib/xml/qxmlutils.cpp
@@ -37,7 +37,6 @@
 **
 ****************************************************************************/
 
-#include <qregexp.h>
 #include <qstring.h>
 
 #include "qxmlutils_p.h"
@@ -230,14 +229,20 @@ bool QXmlUtils::isBaseChar(const QChar c)
  */
 bool QXmlUtils::isEncName(const QString &encName)
 {
-    /* Right, we here have a dependency on QRegExp. Writing a manual parser to
-     * replace that regexp is probably a 70 lines so I prioritize this to when
-     * the dependency is considered alarming, or when the rest of the bugs
-     * are fixed. */
-    QRegExp encNameRegExp(QLatin1String("[A-Za-z][A-Za-z0-9._\\-]*"));
-    Q_ASSERT(encNameRegExp.isValid());
-
-    return encNameRegExp.exactMatch(encName);
+    // Valid encoding names are given by "[A-Za-z][A-Za-z0-9._\\-]*"
+    const ushort *c = encName.utf16();
+    int l = encName.length();
+    if (l < 1 || !((c[0] >= 'a' && c[0] <= 'z') || (c[0] >= 'A' && c[0] <= 'Z')))
+        return false;
+    for (int i = 1; i < l; ++i) {
+        if ((c[i] >= 'a' && c[i] <= 'z')
+            || (c[i] >= 'A' && c[i] <= 'Z')
+            || (c[i] >= '0' && c[i] <= '9')
+            || c[i] == '.' || c[i] == '_' || c[i] == '-')
+            continue;
+        return false;
+    }
+    return true;
 }
 
 /*!