WebCore/platform/KURL.cpp
changeset 0 4f2f89ce4247
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/WebCore/platform/KURL.cpp	Fri Sep 17 09:02:29 2010 +0300
@@ -0,0 +1,1829 @@
+/*
+ * Copyright (C) 2004, 2007, 2008 Apple Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
+ */
+
+#include "config.h"
+
+#if !USE(GOOGLEURL)
+
+#include "KURL.h"
+
+#include "StringHash.h"
+#include "TextEncoding.h"
+#include <wtf/text/CString.h>
+#include <wtf/HashMap.h>
+#include <wtf/StdLibExtras.h>
+
+#if USE(ICU_UNICODE)
+#include <unicode/uidna.h>
+#elif USE(QT4_UNICODE)
+#include <QUrl>
+#elif USE(GLIB_UNICODE)
+#include <glib.h>
+#include "GOwnPtr.h"
+#endif
+
+#include <stdio.h>
+
+using namespace std;
+using namespace WTF;
+
+namespace WebCore {
+
+typedef Vector<char, 512> CharBuffer;
+typedef Vector<UChar, 512> UCharBuffer;
+
+// FIXME: This file makes too much use of the + operator on String.
+// We either have to optimize that operator so it doesn't involve
+// so many allocations, or change this to use Vector<UChar> instead.
+
+enum URLCharacterClasses {
+    // alpha 
+    SchemeFirstChar = 1 << 0,
+
+    // ( alpha | digit | "+" | "-" | "." )
+    SchemeChar = 1 << 1,
+
+    // mark        = "-" | "_" | "." | "!" | "~" | "*" | "'" | "(" | ")"
+    // unreserved  = alphanum | mark
+    // ( unreserved | escaped | ";" | ":" | "&" | "=" | "+" | "$" | "," )
+    UserInfoChar = 1 << 2,
+
+    // alnum | "." | "-" | "%"
+    // The above is what the specification says, but we are lenient to
+    // match existing practice and also allow:
+    // "_"
+    HostnameChar = 1 << 3,
+
+    // hexdigit | ":" | "%"
+    IPv6Char = 1 << 4,
+
+    // "#" | "?" | "/" | nul
+    PathSegmentEndChar = 1 << 5,
+
+    // not allowed in path
+    BadChar = 1 << 6
+};
+
+static const char hexDigits[17] = "0123456789ABCDEF";
+
+static const unsigned char characterClassTable[256] = {
+    /* 0 nul */ PathSegmentEndChar,    /* 1 soh */ BadChar,
+    /* 2 stx */ BadChar,    /* 3 etx */ BadChar,
+    /* 4 eot */ BadChar,    /* 5 enq */ BadChar,    /* 6 ack */ BadChar,    /* 7 bel */ BadChar,
+    /* 8 bs */ BadChar,     /* 9 ht */ BadChar,     /* 10 nl */ BadChar,    /* 11 vt */ BadChar,
+    /* 12 np */ BadChar,    /* 13 cr */ BadChar,    /* 14 so */ BadChar,    /* 15 si */ BadChar,
+    /* 16 dle */ BadChar,   /* 17 dc1 */ BadChar,   /* 18 dc2 */ BadChar,   /* 19 dc3 */ BadChar,
+    /* 20 dc4 */ BadChar,   /* 21 nak */ BadChar,   /* 22 syn */ BadChar,   /* 23 etb */ BadChar,
+    /* 24 can */ BadChar,   /* 25 em */ BadChar,    /* 26 sub */ BadChar,   /* 27 esc */ BadChar,
+    /* 28 fs */ BadChar,    /* 29 gs */ BadChar,    /* 30 rs */ BadChar,    /* 31 us */ BadChar,
+    /* 32 sp */ BadChar,    /* 33  ! */ UserInfoChar,
+    /* 34  " */ BadChar,    /* 35  # */ PathSegmentEndChar | BadChar,
+    /* 36  $ */ UserInfoChar,    /* 37  % */ UserInfoChar | HostnameChar | IPv6Char | BadChar,
+    /* 38  & */ UserInfoChar,    /* 39  ' */ UserInfoChar,
+    /* 40  ( */ UserInfoChar,    /* 41  ) */ UserInfoChar,
+    /* 42  * */ UserInfoChar,    /* 43  + */ SchemeChar | UserInfoChar,
+    /* 44  , */ UserInfoChar,
+    /* 45  - */ SchemeChar | UserInfoChar | HostnameChar,
+    /* 46  . */ SchemeChar | UserInfoChar | HostnameChar | IPv6Char,
+    /* 47  / */ PathSegmentEndChar,
+    /* 48  0 */ SchemeChar | UserInfoChar | HostnameChar | IPv6Char, 
+    /* 49  1 */ SchemeChar | UserInfoChar | HostnameChar | IPv6Char,    
+    /* 50  2 */ SchemeChar | UserInfoChar | HostnameChar | IPv6Char, 
+    /* 51  3 */ SchemeChar | UserInfoChar | HostnameChar | IPv6Char,
+    /* 52  4 */ SchemeChar | UserInfoChar | HostnameChar | IPv6Char, 
+    /* 53  5 */ SchemeChar | UserInfoChar | HostnameChar | IPv6Char,
+    /* 54  6 */ SchemeChar | UserInfoChar | HostnameChar | IPv6Char, 
+    /* 55  7 */ SchemeChar | UserInfoChar | HostnameChar | IPv6Char,
+    /* 56  8 */ SchemeChar | UserInfoChar | HostnameChar | IPv6Char, 
+    /* 57  9 */ SchemeChar | UserInfoChar | HostnameChar | IPv6Char,
+    /* 58  : */ UserInfoChar | IPv6Char,    /* 59  ; */ UserInfoChar,
+    /* 60  < */ BadChar,    /* 61  = */ UserInfoChar,
+    /* 62  > */ BadChar,    /* 63  ? */ PathSegmentEndChar | BadChar,
+    /* 64  @ */ 0,
+    /* 65  A */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar | IPv6Char,    
+    /* 66  B */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar | IPv6Char,
+    /* 67  C */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar | IPv6Char,
+    /* 68  D */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar | IPv6Char,
+    /* 69  E */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar | IPv6Char,
+    /* 70  F */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar | IPv6Char,
+    /* 71  G */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar,
+    /* 72  H */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar,
+    /* 73  I */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar,
+    /* 74  J */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar,
+    /* 75  K */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar,
+    /* 76  L */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar,
+    /* 77  M */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar,
+    /* 78  N */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar,
+    /* 79  O */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar,
+    /* 80  P */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar,
+    /* 81  Q */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar,
+    /* 82  R */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar,
+    /* 83  S */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar,
+    /* 84  T */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar,
+    /* 85  U */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar,
+    /* 86  V */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar,
+    /* 87  W */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar,
+    /* 88  X */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar, 
+    /* 89  Y */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar,
+    /* 90  Z */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar,
+    /* 91  [ */ 0,
+    /* 92  \ */ 0,    /* 93  ] */ 0,
+    /* 94  ^ */ 0,
+    /* 95  _ */ UserInfoChar | HostnameChar,
+    /* 96  ` */ 0,
+    /* 97  a */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar | IPv6Char,
+    /* 98  b */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar | IPv6Char, 
+    /* 99  c */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar | IPv6Char,
+    /* 100  d */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar | IPv6Char, 
+    /* 101  e */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar | IPv6Char,
+    /* 102  f */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar | IPv6Char, 
+    /* 103  g */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar,
+    /* 104  h */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar, 
+    /* 105  i */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar,
+    /* 106  j */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar, 
+    /* 107  k */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar,
+    /* 108  l */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar, 
+    /* 109  m */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar,
+    /* 110  n */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar, 
+    /* 111  o */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar,
+    /* 112  p */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar, 
+    /* 113  q */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar,
+    /* 114  r */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar, 
+    /* 115  s */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar,
+    /* 116  t */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar, 
+    /* 117  u */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar,
+    /* 118  v */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar, 
+    /* 119  w */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar,
+    /* 120  x */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar, 
+    /* 121  y */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar,
+    /* 122  z */ SchemeFirstChar | SchemeChar | UserInfoChar | HostnameChar, 
+    /* 123  { */ 0,
+    /* 124  | */ 0,   /* 125  } */ 0,   /* 126  ~ */ UserInfoChar,   /* 127 del */ BadChar,
+    /* 128 */ BadChar, /* 129 */ BadChar, /* 130 */ BadChar, /* 131 */ BadChar,
+    /* 132 */ BadChar, /* 133 */ BadChar, /* 134 */ BadChar, /* 135 */ BadChar,
+    /* 136 */ BadChar, /* 137 */ BadChar, /* 138 */ BadChar, /* 139 */ BadChar,
+    /* 140 */ BadChar, /* 141 */ BadChar, /* 142 */ BadChar, /* 143 */ BadChar,
+    /* 144 */ BadChar, /* 145 */ BadChar, /* 146 */ BadChar, /* 147 */ BadChar,
+    /* 148 */ BadChar, /* 149 */ BadChar, /* 150 */ BadChar, /* 151 */ BadChar,
+    /* 152 */ BadChar, /* 153 */ BadChar, /* 154 */ BadChar, /* 155 */ BadChar,
+    /* 156 */ BadChar, /* 157 */ BadChar, /* 158 */ BadChar, /* 159 */ BadChar,
+    /* 160 */ BadChar, /* 161 */ BadChar, /* 162 */ BadChar, /* 163 */ BadChar,
+    /* 164 */ BadChar, /* 165 */ BadChar, /* 166 */ BadChar, /* 167 */ BadChar,
+    /* 168 */ BadChar, /* 169 */ BadChar, /* 170 */ BadChar, /* 171 */ BadChar,
+    /* 172 */ BadChar, /* 173 */ BadChar, /* 174 */ BadChar, /* 175 */ BadChar,
+    /* 176 */ BadChar, /* 177 */ BadChar, /* 178 */ BadChar, /* 179 */ BadChar,
+    /* 180 */ BadChar, /* 181 */ BadChar, /* 182 */ BadChar, /* 183 */ BadChar,
+    /* 184 */ BadChar, /* 185 */ BadChar, /* 186 */ BadChar, /* 187 */ BadChar,
+    /* 188 */ BadChar, /* 189 */ BadChar, /* 190 */ BadChar, /* 191 */ BadChar,
+    /* 192 */ BadChar, /* 193 */ BadChar, /* 194 */ BadChar, /* 195 */ BadChar,
+    /* 196 */ BadChar, /* 197 */ BadChar, /* 198 */ BadChar, /* 199 */ BadChar,
+    /* 200 */ BadChar, /* 201 */ BadChar, /* 202 */ BadChar, /* 203 */ BadChar,
+    /* 204 */ BadChar, /* 205 */ BadChar, /* 206 */ BadChar, /* 207 */ BadChar,
+    /* 208 */ BadChar, /* 209 */ BadChar, /* 210 */ BadChar, /* 211 */ BadChar,
+    /* 212 */ BadChar, /* 213 */ BadChar, /* 214 */ BadChar, /* 215 */ BadChar,
+    /* 216 */ BadChar, /* 217 */ BadChar, /* 218 */ BadChar, /* 219 */ BadChar,
+    /* 220 */ BadChar, /* 221 */ BadChar, /* 222 */ BadChar, /* 223 */ BadChar,
+    /* 224 */ BadChar, /* 225 */ BadChar, /* 226 */ BadChar, /* 227 */ BadChar,
+    /* 228 */ BadChar, /* 229 */ BadChar, /* 230 */ BadChar, /* 231 */ BadChar,
+    /* 232 */ BadChar, /* 233 */ BadChar, /* 234 */ BadChar, /* 235 */ BadChar,
+    /* 236 */ BadChar, /* 237 */ BadChar, /* 238 */ BadChar, /* 239 */ BadChar,
+    /* 240 */ BadChar, /* 241 */ BadChar, /* 242 */ BadChar, /* 243 */ BadChar,
+    /* 244 */ BadChar, /* 245 */ BadChar, /* 246 */ BadChar, /* 247 */ BadChar,
+    /* 248 */ BadChar, /* 249 */ BadChar, /* 250 */ BadChar, /* 251 */ BadChar,
+    /* 252 */ BadChar, /* 253 */ BadChar, /* 254 */ BadChar, /* 255 */ BadChar
+};
+
+static const unsigned maximumValidPortNumber = 0xFFFE;
+static const unsigned invalidPortNumber = 0xFFFF;
+
+static int copyPathRemovingDots(char* dst, const char* src, int srcStart, int srcEnd);
+static void encodeRelativeString(const String& rel, const TextEncoding&, CharBuffer& ouput);
+static String substituteBackslashes(const String&);
+static bool isValidProtocol(const String&);
+
+static inline bool isSchemeFirstChar(char c) { return characterClassTable[static_cast<unsigned char>(c)] & SchemeFirstChar; }
+static inline bool isSchemeFirstChar(UChar c) { return c <= 0xff && (characterClassTable[c] & SchemeFirstChar); }
+static inline bool isSchemeChar(char c) { return characterClassTable[static_cast<unsigned char>(c)] & SchemeChar; }
+static inline bool isSchemeChar(UChar c) { return c <= 0xff && (characterClassTable[c] & SchemeChar); }
+static inline bool isUserInfoChar(unsigned char c) { return characterClassTable[c] & UserInfoChar; }
+static inline bool isHostnameChar(unsigned char c) { return characterClassTable[c] & HostnameChar; }
+static inline bool isIPv6Char(unsigned char c) { return characterClassTable[c] & IPv6Char; }
+static inline bool isPathSegmentEndChar(char c) { return characterClassTable[static_cast<unsigned char>(c)] & PathSegmentEndChar; }
+static inline bool isPathSegmentEndChar(UChar c) { return c <= 0xff && (characterClassTable[c] & PathSegmentEndChar); }
+static inline bool isBadChar(unsigned char c) { return characterClassTable[c] & BadChar; }
+
+static inline int hexDigitValue(UChar c)
+{
+    ASSERT(isASCIIHexDigit(c));
+    if (c < 'A')
+        return c - '0';
+    return (c - 'A' + 10) & 0xF; // handle both upper and lower case without a branch
+}
+
+// Copies the source to the destination, assuming all the source characters are
+// ASCII. The destination buffer must be large enough. Null characters are allowed
+// in the source string, and no attempt is made to null-terminate the result.
+static void copyASCII(const UChar* src, int length, char* dest)
+{
+    for (int i = 0; i < length; i++)
+        dest[i] = static_cast<char>(src[i]);
+}
+
+static void appendASCII(const String& base, const char* rel, size_t len, CharBuffer& buffer)
+{
+    buffer.resize(base.length() + len + 1);
+    copyASCII(base.characters(), base.length(), buffer.data());
+    memcpy(buffer.data() + base.length(), rel, len);
+    buffer[buffer.size() - 1] = '\0';
+}
+
+// FIXME: Move to PlatformString.h eventually.
+// Returns the index of the first index in string |s| of any of the characters
+// in |toFind|. |toFind| should be a null-terminated string, all characters up
+// to the null will be searched. Returns int if not found.
+static int findFirstOf(const UChar* s, int sLen, int startPos, const char* toFind)
+{
+    for (int i = startPos; i < sLen; i++) {
+        const char* cur = toFind;
+        while (*cur) {
+            if (s[i] == *(cur++))
+                return i;
+        }
+    }
+    return -1;
+}
+
+#ifndef NDEBUG
+static void checkEncodedString(const String& url)
+{
+    for (unsigned i = 0; i < url.length(); ++i)
+        ASSERT(!(url[i] & ~0x7F));
+
+    ASSERT(!url.length() || isSchemeFirstChar(url[0]));
+}
+#else
+static inline void checkEncodedString(const String&)
+{
+}
+#endif
+
+inline bool KURL::protocolIs(const String& string, const char* protocol)
+{
+    return WebCore::protocolIs(string, protocol);
+}
+
+void KURL::invalidate()
+{
+    m_isValid = false;
+    m_protocolInHTTPFamily = false;
+    m_schemeEnd = 0;
+    m_userStart = 0;
+    m_userEnd = 0;
+    m_passwordEnd = 0;
+    m_hostEnd = 0;
+    m_portEnd = 0;
+    m_pathEnd = 0;
+    m_pathAfterLastSlash = 0;
+    m_queryEnd = 0;
+    m_fragmentEnd = 0;
+}
+
+KURL::KURL(ParsedURLStringTag, const char* url)
+{
+    parse(url, 0);
+    ASSERT(url == m_string);
+}
+
+KURL::KURL(ParsedURLStringTag, const String& url)
+{
+    parse(url);
+    ASSERT(url == m_string);
+}
+
+KURL::KURL(const KURL& base, const String& relative)
+{
+    init(base, relative, UTF8Encoding());
+}
+
+KURL::KURL(const KURL& base, const String& relative, const TextEncoding& encoding)
+{
+    // For UTF-{7,16,32}, we want to use UTF-8 for the query part as 
+    // we do when submitting a form. A form with GET method
+    // has its contents added to a URL as query params and it makes sense
+    // to be consistent.
+    init(base, relative, encoding.encodingForFormSubmission());
+}
+
+void KURL::init(const KURL& base, const String& relative, const TextEncoding& encoding)
+{
+    // Allow resolutions with a null or empty base URL, but not with any other invalid one.
+    // FIXME: Is this a good rule?
+    if (!base.m_isValid && !base.isEmpty()) {
+        m_string = relative;
+        invalidate();
+        return;
+    }
+
+    // For compatibility with Win IE, treat backslashes as if they were slashes,
+    // as long as we're not dealing with javascript: or data: URLs.
+    String rel = relative;
+    if (rel.contains('\\') && !(protocolIsJavaScript(rel) || protocolIs(rel, "data")))
+        rel = substituteBackslashes(rel);
+
+    String* originalString = &rel;
+
+    bool allASCII = charactersAreAllASCII(rel.characters(), rel.length());
+    CharBuffer strBuffer;
+    char* str;
+    size_t len;
+    if (allASCII) {
+        len = rel.length();
+        strBuffer.resize(len + 1);
+        copyASCII(rel.characters(), len, strBuffer.data());
+        strBuffer[len] = 0;
+        str = strBuffer.data();
+    } else {
+        originalString = 0;
+        encodeRelativeString(rel, encoding, strBuffer);
+        str = strBuffer.data();
+        len = strlen(str);
+    }
+
+    // Get rid of leading whitespace.
+    while (*str == ' ') {
+        originalString = 0;
+        str++;
+        --len;
+    }
+
+    // Get rid of trailing whitespace.
+    while (len && str[len - 1] == ' ') {
+        originalString = 0;
+        str[--len] = '\0';
+    }
+
+    // According to the RFC, the reference should be interpreted as an
+    // absolute URI if possible, using the "leftmost, longest"
+    // algorithm. If the URI reference is absolute it will have a
+    // scheme, meaning that it will have a colon before the first
+    // non-scheme element.
+    bool absolute = false;
+    char* p = str;
+    if (isSchemeFirstChar(*p)) {
+        ++p;
+        while (isSchemeChar(*p)) {
+            ++p;
+        }
+        if (*p == ':') {
+            if (p[1] != '/' && equalIgnoringCase(base.protocol(), String(str, p - str)) && base.isHierarchical()) {
+                str = p + 1;
+                originalString = 0;
+            } else
+                absolute = true;
+        }
+    }
+
+    CharBuffer parseBuffer;
+
+    if (absolute) {
+        parse(str, originalString);
+    } else {
+        // If the base is empty or opaque (e.g. data: or javascript:), then the URL is invalid
+        // unless the relative URL is a single fragment.
+        if (!base.isHierarchical()) {
+            if (str[0] == '#') {
+                appendASCII(base.m_string.left(base.m_queryEnd), str, len, parseBuffer);
+                parse(parseBuffer.data(), 0);
+            } else {
+                m_string = relative;
+                invalidate();
+            }
+            return;
+        }
+
+        switch (str[0]) {
+        case '\0':
+            // The reference is empty, so this is a reference to the same document with any fragment identifier removed.
+            *this = base;
+            removeFragmentIdentifier();
+            break;
+        case '#': {
+            // must be fragment-only reference
+            appendASCII(base.m_string.left(base.m_queryEnd), str, len, parseBuffer);
+            parse(parseBuffer.data(), 0);
+            break;
+        }
+        case '?': {
+            // query-only reference, special case needed for non-URL results
+            appendASCII(base.m_string.left(base.m_pathEnd), str, len, parseBuffer);
+            parse(parseBuffer.data(), 0);
+            break;
+        }
+        case '/':
+            // must be net-path or absolute-path reference
+            if (str[1] == '/') {
+                // net-path
+                appendASCII(base.m_string.left(base.m_schemeEnd + 1), str, len, parseBuffer);
+                parse(parseBuffer.data(), 0);
+            } else {
+                // abs-path
+                appendASCII(base.m_string.left(base.m_portEnd), str, len, parseBuffer);
+                parse(parseBuffer.data(), 0);
+            }
+            break;
+        default:
+            {
+                // must be relative-path reference
+
+                // Base part plus relative part plus one possible slash added in between plus terminating \0 byte.
+                parseBuffer.resize(base.m_pathEnd + 1 + len + 1);
+
+                char* bufferPos = parseBuffer.data();
+
+                // first copy everything before the path from the base
+                unsigned baseLength = base.m_string.length();
+                const UChar* baseCharacters = base.m_string.characters();
+                CharBuffer baseStringBuffer(baseLength);
+                copyASCII(baseCharacters, baseLength, baseStringBuffer.data());
+                const char* baseString = baseStringBuffer.data();
+                const char* baseStringStart = baseString;
+                const char* pathStart = baseStringStart + base.m_portEnd;
+                while (baseStringStart < pathStart)
+                    *bufferPos++ = *baseStringStart++;
+                char* bufferPathStart = bufferPos;
+
+                // now copy the base path
+                const char* baseStringEnd = baseString + base.m_pathEnd;
+
+                // go back to the last slash
+                while (baseStringEnd > baseStringStart && baseStringEnd[-1] != '/')
+                    baseStringEnd--;
+
+                if (baseStringEnd == baseStringStart) {
+                    // no path in base, add a path separator if necessary
+                    if (base.m_schemeEnd + 1 != base.m_pathEnd && *str && *str != '?' && *str != '#')
+                        *bufferPos++ = '/';
+                } else {
+                    bufferPos += copyPathRemovingDots(bufferPos, baseStringStart, 0, baseStringEnd - baseStringStart);
+                }
+
+                const char* relStringStart = str;
+                const char* relStringPos = relStringStart;
+
+                while (*relStringPos && *relStringPos != '?' && *relStringPos != '#') {
+                    if (relStringPos[0] == '.' && bufferPos[-1] == '/') {
+                        if (isPathSegmentEndChar(relStringPos[1])) {
+                            // skip over "." segment
+                            relStringPos += 1;
+                            if (relStringPos[0] == '/')
+                                relStringPos++;
+                            continue;
+                        } else if (relStringPos[1] == '.' && isPathSegmentEndChar(relStringPos[2])) {
+                            // skip over ".." segment and rewind the last segment
+                            // the RFC leaves it up to the app to decide what to do with excess
+                            // ".." segments - we choose to drop them since some web content
+                            // relies on this.
+                            relStringPos += 2;
+                            if (relStringPos[0] == '/')
+                                relStringPos++;
+                            if (bufferPos > bufferPathStart + 1)
+                                bufferPos--;
+                            while (bufferPos > bufferPathStart + 1  && bufferPos[-1] != '/')
+                                bufferPos--;
+                            continue;
+                        }
+                    }
+
+                    *bufferPos = *relStringPos;
+                    relStringPos++;
+                    bufferPos++;
+                }
+
+                // all done with the path work, now copy any remainder
+                // of the relative reference; this will also add a null terminator
+                strcpy(bufferPos, relStringPos);
+
+                parse(parseBuffer.data(), 0);
+
+                ASSERT(strlen(parseBuffer.data()) + 1 <= parseBuffer.size());
+                break;
+            }
+        }
+    }
+}
+
+KURL KURL::copy() const
+{
+    KURL result = *this;
+    result.m_string = result.m_string.crossThreadString();
+    return result;
+}
+
+bool KURL::hasPath() const
+{
+    return m_pathEnd != m_portEnd;
+}
+
+String KURL::lastPathComponent() const
+{
+    if (!hasPath())
+        return String();
+
+    int end = m_pathEnd - 1;
+    if (m_string[end] == '/')
+        --end;
+
+    int start = m_string.reverseFind('/', end);
+    if (start < m_portEnd)
+        return String();
+    ++start;
+
+    return m_string.substring(start, end - start + 1);
+}
+
+String KURL::protocol() const
+{
+    return m_string.left(m_schemeEnd);
+}
+
+String KURL::host() const
+{
+    int start = hostStart();
+    return decodeURLEscapeSequences(m_string.substring(start, m_hostEnd - start));
+}
+
+unsigned short KURL::port() const
+{
+    // We return a port of 0 if there is no port specified. This can happen in two situations:
+    // 1) The URL contains no colon after the host name and before the path component of the URL.
+    // 2) The URL contains a colon but there's no port number before the path component of the URL begins.
+    if (m_hostEnd == m_portEnd || m_hostEnd == m_portEnd - 1)
+        return 0;
+
+    const UChar* stringData = m_string.characters();
+    bool ok = false;
+    unsigned number = charactersToUIntStrict(stringData + m_hostEnd + 1, m_portEnd - m_hostEnd - 1, &ok);
+    if (!ok || number > maximumValidPortNumber)
+        return invalidPortNumber;
+    return number;
+}
+
+String KURL::pass() const
+{
+    if (m_passwordEnd == m_userEnd)
+        return String();
+
+    return decodeURLEscapeSequences(m_string.substring(m_userEnd + 1, m_passwordEnd - m_userEnd - 1)); 
+}
+
+String KURL::user() const
+{
+    return decodeURLEscapeSequences(m_string.substring(m_userStart, m_userEnd - m_userStart));
+}
+
+String KURL::fragmentIdentifier() const
+{
+    if (m_fragmentEnd == m_queryEnd)
+        return String();
+
+    return m_string.substring(m_queryEnd + 1, m_fragmentEnd - (m_queryEnd + 1));
+}
+
+bool KURL::hasFragmentIdentifier() const
+{
+    return m_fragmentEnd != m_queryEnd;
+}
+
+String KURL::baseAsString() const
+{
+    return m_string.left(m_pathAfterLastSlash);
+}
+
+#ifdef NDEBUG
+
+static inline void assertProtocolIsGood(const char*)
+{
+}
+
+#else
+
+static void assertProtocolIsGood(const char* protocol)
+{
+    const char* p = protocol;
+    while (*p) {
+        ASSERT(*p > ' ' && *p < 0x7F && !(*p >= 'A' && *p <= 'Z'));
+        ++p;
+    }
+}
+
+#endif
+
+bool KURL::protocolIs(const char* protocol) const
+{
+    assertProtocolIsGood(protocol);
+
+    // JavaScript URLs are "valid" and should be executed even if KURL decides they are invalid.
+    // The free function protocolIsJavaScript() should be used instead. 
+    ASSERT(!equalIgnoringCase(protocol, String("javascript")));
+
+    if (!m_isValid)
+        return false;
+
+    // Do the comparison without making a new string object.
+    for (int i = 0; i < m_schemeEnd; ++i) {
+        if (!protocol[i] || toASCIILower(m_string[i]) != protocol[i])
+            return false;
+    }
+    return !protocol[m_schemeEnd]; // We should have consumed all characters in the argument.
+}
+
+String KURL::query() const
+{
+    if (m_queryEnd == m_pathEnd)
+        return String();
+
+    return m_string.substring(m_pathEnd + 1, m_queryEnd - (m_pathEnd + 1)); 
+}
+
+String KURL::path() const
+{
+    return decodeURLEscapeSequences(m_string.substring(m_portEnd, m_pathEnd - m_portEnd)); 
+}
+
+bool KURL::setProtocol(const String& s)
+{
+    // Firefox and IE remove everything after the first ':'.
+    int separatorPosition = s.find(':');
+    String newProtocol = s.substring(0, separatorPosition);
+
+    if (!isValidProtocol(newProtocol))
+        return false;
+
+    if (!m_isValid) {
+        parse(newProtocol + ":" + m_string);
+        return true;
+    }
+
+    parse(newProtocol + m_string.substring(m_schemeEnd));
+    return true;
+}
+
+void KURL::setHost(const String& s)
+{
+    if (!m_isValid)
+        return;
+
+    // FIXME: Non-ASCII characters must be encoded and escaped to match parse() expectations,
+    // and to avoid changing more than just the host.
+
+    bool slashSlashNeeded = m_userStart == m_schemeEnd + 1;
+
+    parse(m_string.left(hostStart()) + (slashSlashNeeded ? "//" : "") + s + m_string.substring(m_hostEnd));
+}
+
+void KURL::removePort()
+{
+    if (m_hostEnd == m_portEnd)
+        return;
+    parse(m_string.left(m_hostEnd) + m_string.substring(m_portEnd));
+}
+
+void KURL::setPort(unsigned short i)
+{
+    if (!m_isValid)
+        return;
+
+    bool colonNeeded = m_portEnd == m_hostEnd;
+    int portStart = (colonNeeded ? m_hostEnd : m_hostEnd + 1);
+
+    parse(m_string.left(portStart) + (colonNeeded ? ":" : "") + String::number(i) + m_string.substring(m_portEnd));
+}
+
+void KURL::setHostAndPort(const String& hostAndPort)
+{
+    if (!m_isValid)
+        return;
+
+    // FIXME: Non-ASCII characters must be encoded and escaped to match parse() expectations,
+    // and to avoid changing more than just host and port.
+
+    bool slashSlashNeeded = m_userStart == m_schemeEnd + 1;
+
+    parse(m_string.left(hostStart()) + (slashSlashNeeded ? "//" : "") + hostAndPort + m_string.substring(m_portEnd));
+}
+
+void KURL::setUser(const String& user)
+{
+    if (!m_isValid)
+        return;
+
+    // FIXME: Non-ASCII characters must be encoded and escaped to match parse() expectations,
+    // and to avoid changing more than just the user login.
+    String u;
+    int end = m_userEnd;
+    if (!user.isEmpty()) {
+        u = user;
+        if (m_userStart == m_schemeEnd + 1)
+            u = "//" + u;
+        // Add '@' if we didn't have one before.
+        if (end == m_hostEnd || (end == m_passwordEnd && m_string[end] != '@'))
+            u.append('@');
+    } else {
+        // Remove '@' if we now have neither user nor password.
+        if (m_userEnd == m_passwordEnd && end != m_hostEnd && m_string[end] == '@')
+            end += 1;
+    }
+    parse(m_string.left(m_userStart) + u + m_string.substring(end));
+}
+
+void KURL::setPass(const String& password)
+{
+    if (!m_isValid)
+        return;
+
+    // FIXME: Non-ASCII characters must be encoded and escaped to match parse() expectations,
+    // and to avoid changing more than just the user password.
+    String p;
+    int end = m_passwordEnd;
+    if (!password.isEmpty()) {
+        p = ":" + password + "@";
+        if (m_userEnd == m_schemeEnd + 1)
+            p = "//" + p;
+        // Eat the existing '@' since we are going to add our own.
+        if (end != m_hostEnd && m_string[end] == '@')
+            end += 1;
+    } else {
+        // Remove '@' if we now have neither user nor password.
+        if (m_userStart == m_userEnd && end != m_hostEnd && m_string[end] == '@')
+            end += 1;
+    }
+    parse(m_string.left(m_userEnd) + p + m_string.substring(end));
+}
+
+void KURL::setFragmentIdentifier(const String& s)
+{
+    if (!m_isValid)
+        return;
+
+    // FIXME: Non-ASCII characters must be encoded and escaped to match parse() expectations.
+    parse(m_string.left(m_queryEnd) + "#" + s);
+}
+
+void KURL::removeFragmentIdentifier()
+{
+    if (!m_isValid)
+        return;
+    parse(m_string.left(m_queryEnd));
+}
+    
+void KURL::setQuery(const String& query)
+{
+    if (!m_isValid)
+        return;
+
+    // FIXME: '#' and non-ASCII characters must be encoded and escaped.
+    // Usually, the query is encoded using document encoding, not UTF-8, but we don't have
+    // access to the document in this function.
+    if ((query.isEmpty() || query[0] != '?') && !query.isNull())
+        parse(m_string.left(m_pathEnd) + "?" + query + m_string.substring(m_queryEnd));
+    else
+        parse(m_string.left(m_pathEnd) + query + m_string.substring(m_queryEnd));
+
+}
+
+void KURL::setPath(const String& s)
+{
+    if (!m_isValid)
+        return;
+
+    // FIXME: encodeWithURLEscapeSequences does not correctly escape '#' and '?', so fragment and query parts
+    // may be inadvertently affected.
+    parse(m_string.left(m_portEnd) + encodeWithURLEscapeSequences(s) + m_string.substring(m_pathEnd));
+}
+
+String KURL::prettyURL() const
+{
+    if (!m_isValid)
+        return m_string;
+
+    Vector<UChar> result;
+
+    append(result, protocol());
+    result.append(':');
+
+    Vector<UChar> authority;
+
+    if (m_hostEnd != m_passwordEnd) {
+        if (m_userEnd != m_userStart) {
+            append(authority, user());
+            authority.append('@');
+        }
+        append(authority, host());
+        if (hasPort()) {
+            authority.append(':');
+            append(authority, String::number(port()));
+        }
+    }
+
+    if (!authority.isEmpty()) {
+        result.append('/');
+        result.append('/');
+        result.append(authority);
+    } else if (protocolIs("file")) {
+        result.append('/');
+        result.append('/');
+    }
+
+    append(result, path());
+
+    if (m_pathEnd != m_queryEnd) {
+        result.append('?');
+        append(result, query());
+    }
+
+    if (m_fragmentEnd != m_queryEnd) {
+        result.append('#');
+        append(result, fragmentIdentifier());
+    }
+
+    return String::adopt(result);
+}
+
+String decodeURLEscapeSequences(const String& str)
+{
+    return decodeURLEscapeSequences(str, UTF8Encoding());
+}
+
+String decodeURLEscapeSequences(const String& str, const TextEncoding& encoding)
+{
+    Vector<UChar> result;
+
+    CharBuffer buffer;
+
+    int length = str.length();
+    int decodedPosition = 0;
+    int searchPosition = 0;
+    int encodedRunPosition;
+    while ((encodedRunPosition = str.find('%', searchPosition)) >= 0) {
+        // Find the sequence of %-escape codes.
+        int encodedRunEnd = encodedRunPosition;
+        while (length - encodedRunEnd >= 3
+                && str[encodedRunEnd] == '%'
+                && isASCIIHexDigit(str[encodedRunEnd + 1])
+                && isASCIIHexDigit(str[encodedRunEnd + 2]))
+            encodedRunEnd += 3;
+        if (encodedRunEnd == encodedRunPosition) {
+            ++searchPosition;
+            continue;
+        }
+        searchPosition = encodedRunEnd;
+
+        // Decode the %-escapes into bytes.
+        unsigned runLength = (encodedRunEnd - encodedRunPosition) / 3;
+        buffer.resize(runLength);
+        char* p = buffer.data();
+        const UChar* q = str.characters() + encodedRunPosition;
+        for (unsigned i = 0; i < runLength; ++i) {
+            *p++ = (hexDigitValue(q[1]) << 4) | hexDigitValue(q[2]);
+            q += 3;
+        }
+
+        // Decode the bytes into Unicode characters.
+        String decoded = (encoding.isValid() ? encoding : UTF8Encoding()).decode(buffer.data(), p - buffer.data());
+        if (decoded.isEmpty())
+            continue;
+
+        // Build up the string with what we just skipped and what we just decoded.
+        result.append(str.characters() + decodedPosition, encodedRunPosition - decodedPosition);
+        result.append(decoded.characters(), decoded.length());
+        decodedPosition = encodedRunEnd;
+    }
+
+    result.append(str.characters() + decodedPosition, length - decodedPosition);
+
+    return String::adopt(result);
+}
+
+bool KURL::isLocalFile() const
+{
+    // Including feed here might be a bad idea since drag and drop uses this check
+    // and including feed would allow feeds to potentially let someone's blog
+    // read the contents of the clipboard on a drag, even without a drop.
+    // Likewise with using the FrameLoader::shouldTreatURLAsLocal() function.
+    return protocolIs("file");
+}
+
+static void appendEscapingBadChars(char*& buffer, const char* strStart, size_t length)
+{
+    char* p = buffer;
+
+    const char* str = strStart;
+    const char* strEnd = strStart + length;
+    while (str < strEnd) {
+        unsigned char c = *str++;
+        if (isBadChar(c)) {
+            if (c == '%' || c == '?') {
+                *p++ = c;
+            } else if (c != 0x09 && c != 0x0a && c != 0x0d) {
+                *p++ = '%';
+                *p++ = hexDigits[c >> 4];
+                *p++ = hexDigits[c & 0xF];
+            }
+        } else {
+            *p++ = c;
+        }
+    }
+
+    buffer = p;
+}
+
+// copy a path, accounting for "." and ".." segments
+static int copyPathRemovingDots(char* dst, const char* src, int srcStart, int srcEnd)
+{
+    char* bufferPathStart = dst;
+
+    // empty path is a special case, and need not have a leading slash
+    if (srcStart != srcEnd) {
+        const char* baseStringStart = src + srcStart;
+        const char* baseStringEnd = src + srcEnd;
+        const char* baseStringPos = baseStringStart;
+
+        // this code is unprepared for paths that do not begin with a
+        // slash and we should always have one in the source string
+        ASSERT(baseStringPos[0] == '/');
+
+        // copy the leading slash into the destination
+        *dst = *baseStringPos;
+        baseStringPos++;
+        dst++;
+
+        while (baseStringPos < baseStringEnd) {
+            if (baseStringPos[0] == '.' && dst[-1] == '/') {
+                if (baseStringPos[1] == '/' || baseStringPos + 1 == baseStringEnd) {
+                    // skip over "." segment
+                    baseStringPos += 2;
+                    continue;
+                } else if (baseStringPos[1] == '.' && (baseStringPos[2] == '/' ||
+                                       baseStringPos + 2 == baseStringEnd)) {
+                    // skip over ".." segment and rewind the last segment
+                    // the RFC leaves it up to the app to decide what to do with excess
+                    // ".." segments - we choose to drop them since some web content
+                    // relies on this.
+                    baseStringPos += 3;
+                    if (dst > bufferPathStart + 1)
+                        dst--;
+                    // Note that these two while blocks differ subtly.
+                    // The first helps to remove multiple adjoining slashes as we rewind.
+                    // The +1 to bufferPathStart in the first while block prevents eating a leading slash
+                    while (dst > bufferPathStart + 1 && dst[-1] == '/')
+                        dst--;
+                    while (dst > bufferPathStart && dst[-1] != '/')
+                        dst--;
+                    continue;
+                }
+            }
+
+            *dst = *baseStringPos;
+            baseStringPos++;
+            dst++;
+        }
+    }
+    *dst = '\0';
+    return dst - bufferPathStart;
+}
+
+static inline bool hasSlashDotOrDotDot(const char* str)
+{
+    const unsigned char* p = reinterpret_cast<const unsigned char*>(str);
+    if (!*p)
+        return false;
+    unsigned char pc = *p;
+    while (unsigned char c = *++p) {
+        if (c == '.' && (pc == '/' || pc == '.'))
+            return true;
+        pc = c;
+    }
+    return false;
+}
+
+static inline bool matchLetter(char c, char lowercaseLetter)
+{
+    return (c | 0x20) == lowercaseLetter;
+}
+
+void KURL::parse(const String& string)
+{
+    checkEncodedString(string);
+
+    CharBuffer buffer(string.length() + 1);
+    copyASCII(string.characters(), string.length(), buffer.data());
+    buffer[string.length()] = '\0';
+    parse(buffer.data(), &string);
+}
+
+void KURL::parse(const char* url, const String* originalString)
+{
+    if (!url || url[0] == '\0') {
+        // valid URL must be non-empty
+        m_string = originalString ? *originalString : url;
+        invalidate();
+        return;
+    }
+
+    if (!isSchemeFirstChar(url[0])) {
+        // scheme must start with an alphabetic character
+        m_string = originalString ? *originalString : url;
+        invalidate();
+        return;
+    }
+
+    int schemeEnd = 0;
+    while (isSchemeChar(url[schemeEnd]))
+        schemeEnd++;
+
+    if (url[schemeEnd] != ':') {
+        m_string = originalString ? *originalString : url;
+        invalidate();
+        return;
+    }
+
+    int userStart = schemeEnd + 1;
+    int userEnd;
+    int passwordStart;
+    int passwordEnd;
+    int hostStart;
+    int hostEnd;
+    int portStart;
+    int portEnd;
+
+    bool hierarchical = url[schemeEnd + 1] == '/';
+
+    bool isFile = schemeEnd == 4
+        && matchLetter(url[0], 'f')
+        && matchLetter(url[1], 'i')
+        && matchLetter(url[2], 'l')
+        && matchLetter(url[3], 'e');
+
+    m_protocolInHTTPFamily = matchLetter(url[0], 'h')
+        && matchLetter(url[1], 't')
+        && matchLetter(url[2], 't')
+        && matchLetter(url[3], 'p')
+        && (url[4] == ':' || (matchLetter(url[4], 's') && url[5] == ':'));
+
+    if (hierarchical && url[schemeEnd + 2] == '/') {
+        // The part after the scheme is either a net_path or an abs_path whose first path segment is empty.
+        // Attempt to find an authority.
+
+        // FIXME: Authority characters may be scanned twice, and it would be nice to be faster.
+        userStart += 2;
+        userEnd = userStart;
+
+        int colonPos = 0;
+        while (isUserInfoChar(url[userEnd])) {
+            if (url[userEnd] == ':' && colonPos == 0)
+                colonPos = userEnd;
+            userEnd++;
+        }
+
+        if (url[userEnd] == '@') {
+            // actual end of the userinfo, start on the host
+            if (colonPos != 0) {
+                passwordEnd = userEnd;
+                userEnd = colonPos;
+                passwordStart = colonPos + 1;
+            } else
+                passwordStart = passwordEnd = userEnd;
+
+            hostStart = passwordEnd + 1;
+        } else if (url[userEnd] == '[' || isPathSegmentEndChar(url[userEnd])) {
+            // hit the end of the authority, must have been no user
+            // or looks like an IPv6 hostname
+            // either way, try to parse it as a hostname
+            userEnd = userStart;
+            passwordStart = passwordEnd = userEnd;
+            hostStart = userStart;
+        } else {
+            // invalid character
+            m_string = originalString ? *originalString : url;
+            invalidate();
+            return;
+        }
+
+        hostEnd = hostStart;
+
+        // IPV6 IP address
+        if (url[hostEnd] == '[') {
+            hostEnd++;
+            while (isIPv6Char(url[hostEnd]))
+                hostEnd++;
+            if (url[hostEnd] == ']')
+                hostEnd++;
+            else {
+                // invalid character
+                m_string = originalString ? *originalString : url;
+                invalidate();
+                return;
+            }
+        } else {
+            while (isHostnameChar(url[hostEnd]))
+                hostEnd++;
+        }
+        
+        if (url[hostEnd] == ':') {
+            portStart = portEnd = hostEnd + 1;
+ 
+            // possible start of port
+            portEnd = portStart;
+            while (isASCIIDigit(url[portEnd]))
+                portEnd++;
+        } else
+            portStart = portEnd = hostEnd;
+
+        if (!isPathSegmentEndChar(url[portEnd])) {
+            // invalid character
+            m_string = originalString ? *originalString : url;
+            invalidate();
+            return;
+        }
+
+        if (userStart == portEnd && !m_protocolInHTTPFamily && !isFile) {
+            // No authority found, which means that this is not a net_path, but rather an abs_path whose first two
+            // path segments are empty. For file, http and https only, an empty authority is allowed.
+            userStart -= 2;
+            userEnd = userStart;
+            passwordStart = userEnd;
+            passwordEnd = passwordStart;
+            hostStart = passwordEnd;
+            hostEnd = hostStart;
+            portStart = hostEnd;
+            portEnd = hostEnd;
+        }
+    } else {
+        // the part after the scheme must be an opaque_part or an abs_path
+        userEnd = userStart;
+        passwordStart = passwordEnd = userEnd;
+        hostStart = hostEnd = passwordEnd;
+        portStart = portEnd = hostEnd;
+    }
+
+    int pathStart = portEnd;
+    int pathEnd = pathStart;
+    while (url[pathEnd] && url[pathEnd] != '?' && url[pathEnd] != '#')
+        pathEnd++;
+
+    int queryStart = pathEnd;
+    int queryEnd = queryStart;
+    if (url[queryStart] == '?') {
+        while (url[queryEnd] && url[queryEnd] != '#')
+            queryEnd++;
+    }
+
+    int fragmentStart = queryEnd;
+    int fragmentEnd = fragmentStart;
+    if (url[fragmentStart] == '#') {
+        fragmentStart++;
+        fragmentEnd = fragmentStart;
+        while (url[fragmentEnd])
+            fragmentEnd++;
+    }
+
+    // assemble it all, remembering the real ranges
+
+    Vector<char, 4096> buffer(fragmentEnd * 3 + 1);
+
+    char *p = buffer.data();
+    const char *strPtr = url;
+
+    // copy in the scheme
+    const char *schemeEndPtr = url + schemeEnd;
+    while (strPtr < schemeEndPtr)
+        *p++ = *strPtr++;
+    m_schemeEnd = p - buffer.data();
+
+    bool hostIsLocalHost = portEnd - userStart == 9
+        && matchLetter(url[userStart], 'l')
+        && matchLetter(url[userStart+1], 'o')
+        && matchLetter(url[userStart+2], 'c')
+        && matchLetter(url[userStart+3], 'a')
+        && matchLetter(url[userStart+4], 'l')
+        && matchLetter(url[userStart+5], 'h')
+        && matchLetter(url[userStart+6], 'o')
+        && matchLetter(url[userStart+7], 's')
+        && matchLetter(url[userStart+8], 't');
+
+    // File URLs need a host part unless it is just file:// or file://localhost
+    bool degenFilePath = pathStart == pathEnd && (hostStart == hostEnd || hostIsLocalHost);
+
+    bool haveNonHostAuthorityPart = userStart != userEnd || passwordStart != passwordEnd || portStart != portEnd;
+
+    // add ":" after scheme
+    *p++ = ':';
+
+    // if we have at least one authority part or a file URL - add "//" and authority
+    if (isFile ? !degenFilePath : (haveNonHostAuthorityPart || hostStart != hostEnd)) {
+        *p++ = '/';
+        *p++ = '/';
+
+        m_userStart = p - buffer.data();
+
+        // copy in the user
+        strPtr = url + userStart;
+        const char* userEndPtr = url + userEnd;
+        while (strPtr < userEndPtr)
+            *p++ = *strPtr++;
+        m_userEnd = p - buffer.data();
+
+        // copy in the password
+        if (passwordEnd != passwordStart) {
+            *p++ = ':';
+            strPtr = url + passwordStart;
+            const char* passwordEndPtr = url + passwordEnd;
+            while (strPtr < passwordEndPtr)
+                *p++ = *strPtr++;
+        }
+        m_passwordEnd = p - buffer.data();
+
+        // If we had any user info, add "@"
+        if (p - buffer.data() != m_userStart)
+            *p++ = '@';
+
+        // copy in the host, except in the case of a file URL with authority="localhost"
+        if (!(isFile && hostIsLocalHost && !haveNonHostAuthorityPart)) {
+            strPtr = url + hostStart;
+            const char* hostEndPtr = url + hostEnd;
+            while (strPtr < hostEndPtr)
+                *p++ = *strPtr++;
+        }
+        m_hostEnd = p - buffer.data();
+
+        // copy in the port
+        if (hostEnd != portStart) {
+            *p++ = ':';
+            strPtr = url + portStart;
+            const char *portEndPtr = url + portEnd;
+            while (strPtr < portEndPtr)
+                *p++ = *strPtr++;
+        }
+        m_portEnd = p - buffer.data();
+    } else
+        m_userStart = m_userEnd = m_passwordEnd = m_hostEnd = m_portEnd = p - buffer.data();
+
+    // For canonicalization, ensure we have a '/' for no path.
+    // Do this only for hierarchical URL with protocol http or https.
+    if (m_protocolInHTTPFamily && hierarchical && pathEnd == pathStart)
+        *p++ = '/';
+
+    // add path, escaping bad characters
+    if (!hierarchical || !hasSlashDotOrDotDot(url))
+        appendEscapingBadChars(p, url + pathStart, pathEnd - pathStart);
+    else {
+        CharBuffer pathBuffer(pathEnd - pathStart + 1);
+        size_t length = copyPathRemovingDots(pathBuffer.data(), url, pathStart, pathEnd);
+        appendEscapingBadChars(p, pathBuffer.data(), length);
+    }
+
+    m_pathEnd = p - buffer.data();
+
+    // Find the position after the last slash in the path, or
+    // the position before the path if there are no slashes in it.
+    int i;
+    for (i = m_pathEnd; i > m_portEnd; --i) {
+        if (buffer[i - 1] == '/')
+            break;
+    }
+    m_pathAfterLastSlash = i;
+
+    // add query, escaping bad characters
+    appendEscapingBadChars(p, url + queryStart, queryEnd - queryStart);
+    m_queryEnd = p - buffer.data();
+
+    // add fragment, escaping bad characters
+    if (fragmentEnd != queryEnd) {
+        *p++ = '#';
+        appendEscapingBadChars(p, url + fragmentStart, fragmentEnd - fragmentStart);
+    }
+    m_fragmentEnd = p - buffer.data();
+
+    ASSERT(p - buffer.data() <= static_cast<int>(buffer.size()));
+
+    // If we didn't end up actually changing the original string and
+    // it was already in a String, reuse it to avoid extra allocation.
+    if (originalString && originalString->length() == static_cast<unsigned>(m_fragmentEnd) && strncmp(buffer.data(), url, m_fragmentEnd) == 0)
+        m_string = *originalString;
+    else
+        m_string = String(buffer.data(), m_fragmentEnd);
+
+    m_isValid = true;
+}
+
+bool equalIgnoringFragmentIdentifier(const KURL& a, const KURL& b)
+{
+    if (a.m_queryEnd != b.m_queryEnd)
+        return false;
+    unsigned queryLength = a.m_queryEnd;
+    for (unsigned i = 0; i < queryLength; ++i)
+        if (a.string()[i] != b.string()[i])
+            return false;
+    return true;
+}
+
+bool protocolHostAndPortAreEqual(const KURL& a, const KURL& b)
+{
+    if (a.m_schemeEnd != b.m_schemeEnd)
+        return false;
+
+    int hostStartA = a.hostStart();
+    int hostLengthA = a.hostEnd() - hostStartA;
+    int hostStartB = b.hostStart();
+    int hostLengthB = b.hostEnd() - b.hostStart();
+    if (hostLengthA != hostLengthB)
+        return false;
+
+    // Check the scheme
+    for (int i = 0; i < a.m_schemeEnd; ++i)
+        if (a.string()[i] != b.string()[i])
+            return false;
+
+    // And the host
+    for (int i = 0; i < hostLengthA; ++i)
+        if (a.string()[hostStartA + i] != b.string()[hostStartB + i])
+            return false;
+
+    if (a.port() != b.port())
+        return false;
+
+    return true;
+}
+
+String encodeWithURLEscapeSequences(const String& notEncodedString)
+{
+    CString asUTF8 = notEncodedString.utf8();
+
+    CharBuffer buffer(asUTF8.length() * 3 + 1);
+    char* p = buffer.data();
+
+    const char* str = asUTF8.data();
+    const char* strEnd = str + asUTF8.length();
+    while (str < strEnd) {
+        unsigned char c = *str++;
+        if (isBadChar(c)) {
+            *p++ = '%';
+            *p++ = hexDigits[c >> 4];
+            *p++ = hexDigits[c & 0xF];
+        } else
+            *p++ = c;
+    }
+
+    ASSERT(p - buffer.data() <= static_cast<int>(buffer.size()));
+
+    return String(buffer.data(), p - buffer.data());
+}
+
+// Appends the punycoded hostname identified by the given string and length to
+// the output buffer. The result will not be null terminated.
+static void appendEncodedHostname(UCharBuffer& buffer, const UChar* str, unsigned strLen)
+{
+    // Needs to be big enough to hold an IDN-encoded name.
+    // For host names bigger than this, we won't do IDN encoding, which is almost certainly OK.
+    const unsigned hostnameBufferLength = 2048;
+
+    if (strLen > hostnameBufferLength || charactersAreAllASCII(str, strLen)) {
+        buffer.append(str, strLen);
+        return;
+    }
+
+#if USE(ICU_UNICODE)
+    UChar hostnameBuffer[hostnameBufferLength];
+    UErrorCode error = U_ZERO_ERROR;
+    int32_t numCharactersConverted = uidna_IDNToASCII(str, strLen, hostnameBuffer,
+        hostnameBufferLength, UIDNA_ALLOW_UNASSIGNED, 0, &error);
+    if (error == U_ZERO_ERROR)
+        buffer.append(hostnameBuffer, numCharactersConverted);
+#elif USE(QT4_UNICODE)
+    QByteArray result = QUrl::toAce(String(str, strLen));
+    buffer.append(result.constData(), result.length());
+#elif USE(GLIB_UNICODE)
+    GOwnPtr<gchar> utf8Hostname;
+    GOwnPtr<GError> utf8Err;
+    utf8Hostname.set(g_utf16_to_utf8(str, strLen, 0, 0, &utf8Err.outPtr()));
+    if (utf8Err)
+        return;
+
+    GOwnPtr<gchar> encodedHostname;
+    encodedHostname.set(g_hostname_to_ascii(utf8Hostname.get()));
+    if (!encodedHostname) 
+        return;
+
+    buffer.append(encodedHostname.get(), strlen(encodedHostname.get()));
+#endif
+}
+
+static void findHostnamesInMailToURL(const UChar* str, int strLen, Vector<pair<int, int> >& nameRanges)
+{
+    // In a mailto: URL, host names come after a '@' character and end with a '>' or ',' or '?' or end of string character.
+    // Skip quoted strings so that characters in them don't confuse us.
+    // When we find a '?' character, we are past the part of the URL that contains host names.
+
+    nameRanges.clear();
+
+    int p = 0;
+    while (1) {
+        // Find start of host name or of quoted string.
+        int hostnameOrStringStart = findFirstOf(str, strLen, p, "\"@?");
+        if (hostnameOrStringStart == -1)
+            return;
+        UChar c = str[hostnameOrStringStart];
+        p = hostnameOrStringStart + 1;
+
+        if (c == '?')
+            return;
+
+        if (c == '@') {
+            // Find end of host name.
+            int hostnameStart = p;
+            int hostnameEnd = findFirstOf(str, strLen, p, ">,?");
+            bool done;
+            if (hostnameEnd == -1) {
+                hostnameEnd = strLen;
+                done = true;
+            } else {
+                p = hostnameEnd;
+                done = false;
+            }
+
+            nameRanges.append(make_pair(hostnameStart, hostnameEnd));
+
+            if (done)
+                return;
+        } else {
+            // Skip quoted string.
+            ASSERT(c == '"');
+            while (1) {
+                int escapedCharacterOrStringEnd = findFirstOf(str, strLen, p, "\"\\");
+                if (escapedCharacterOrStringEnd == -1)
+                    return;
+
+                c = str[escapedCharacterOrStringEnd];
+                p = escapedCharacterOrStringEnd + 1;
+
+                // If we are the end of the string, then break from the string loop back to the host name loop.
+                if (c == '"')
+                    break;
+
+                // Skip escaped character.
+                ASSERT(c == '\\');
+                if (p == strLen)
+                    return;
+
+                ++p;
+            }
+        }
+    }
+}
+
+static bool findHostnameInHierarchicalURL(const UChar* str, int strLen, int& startOffset, int& endOffset)
+{
+    // Find the host name in a hierarchical URL.
+    // It comes after a "://" sequence, with scheme characters preceding, and
+    // this should be the first colon in the string.
+    // It ends with the end of the string or a ":" or a path segment ending character.
+    // If there is a "@" character, the host part is just the part after the "@".
+    int separator = findFirstOf(str, strLen, 0, ":");
+    if (separator == -1 || separator + 2 >= strLen ||
+        str[separator + 1] != '/' || str[separator + 2] != '/')
+        return false;
+
+    // Check that all characters before the :// are valid scheme characters.
+    if (!isSchemeFirstChar(str[0]))
+        return false;
+    for (int i = 1; i < separator; ++i) {
+        if (!isSchemeChar(str[i]))
+            return false;
+    }
+
+    // Start after the separator.
+    int authorityStart = separator + 3;
+
+    // Find terminating character.
+    int hostnameEnd = strLen;
+    for (int i = authorityStart; i < strLen; ++i) {
+        UChar c = str[i];
+        if (c == ':' || (isPathSegmentEndChar(c) && c != 0)) {
+            hostnameEnd = i;
+            break;
+        }
+    }
+
+    // Find "@" for the start of the host name.
+    int userInfoTerminator = findFirstOf(str, strLen, authorityStart, "@");
+    int hostnameStart;
+    if (userInfoTerminator == -1 || userInfoTerminator > hostnameEnd)
+        hostnameStart = authorityStart;
+    else
+        hostnameStart = userInfoTerminator + 1;
+
+    startOffset = hostnameStart;
+    endOffset = hostnameEnd;
+    return true;
+}
+
+// Converts all hostnames found in the given input to punycode, preserving the
+// rest of the URL unchanged. The output will NOT be null-terminated.
+static void encodeHostnames(const String& str, UCharBuffer& output)
+{
+    output.clear();
+
+    if (protocolIs(str, "mailto")) {
+        Vector<pair<int, int> > hostnameRanges;
+        findHostnamesInMailToURL(str.characters(), str.length(), hostnameRanges);
+        int n = hostnameRanges.size();
+        int p = 0;
+        for (int i = 0; i < n; ++i) {
+            const pair<int, int>& r = hostnameRanges[i];
+            output.append(&str.characters()[p], r.first - p);
+            appendEncodedHostname(output, &str.characters()[r.first], r.second - r.first);
+            p = r.second;
+        }
+        // This will copy either everything after the last hostname, or the
+        // whole thing if there is no hostname.
+        output.append(&str.characters()[p], str.length() - p);
+    } else {
+        int hostStart, hostEnd;
+        if (findHostnameInHierarchicalURL(str.characters(), str.length(), hostStart, hostEnd)) {
+            output.append(str.characters(), hostStart); // Before hostname.
+            appendEncodedHostname(output, &str.characters()[hostStart], hostEnd - hostStart);
+            output.append(&str.characters()[hostEnd], str.length() - hostEnd); // After hostname.
+        } else {
+            // No hostname to encode, return the input.
+            output.append(str.characters(), str.length());
+        }
+    }
+}
+
+static void encodeRelativeString(const String& rel, const TextEncoding& encoding, CharBuffer& output)
+{
+    UCharBuffer s;
+    encodeHostnames(rel, s);
+
+    TextEncoding pathEncoding(UTF8Encoding()); // Path is always encoded as UTF-8; other parts may depend on the scheme.
+
+    int pathEnd = -1;
+    if (encoding != pathEncoding && encoding.isValid() && !protocolIs(rel, "mailto") && !protocolIs(rel, "data") && !protocolIsJavaScript(rel)) {
+        // Find the first instance of either # or ?, keep pathEnd at -1 otherwise.
+        pathEnd = findFirstOf(s.data(), s.size(), 0, "#?");
+    }
+
+    if (pathEnd == -1) {
+        CString decoded = pathEncoding.encode(s.data(), s.size(), URLEncodedEntitiesForUnencodables);
+        output.resize(decoded.length());
+        memcpy(output.data(), decoded.data(), decoded.length());
+    } else {
+        CString pathDecoded = pathEncoding.encode(s.data(), pathEnd, URLEncodedEntitiesForUnencodables);
+        // Unencodable characters in URLs are represented by converting
+        // them to XML entities and escaping non-alphanumeric characters.
+        CString otherDecoded = encoding.encode(s.data() + pathEnd, s.size() - pathEnd, URLEncodedEntitiesForUnencodables);
+
+        output.resize(pathDecoded.length() + otherDecoded.length());
+        memcpy(output.data(), pathDecoded.data(), pathDecoded.length());
+        memcpy(output.data() + pathDecoded.length(), otherDecoded.data(), otherDecoded.length());
+    }
+    output.append('\0'); // null-terminate the output.
+}
+
+static String substituteBackslashes(const String& string)
+{
+    int questionPos = string.find('?');
+    int hashPos = string.find('#');
+    int pathEnd;
+
+    if (hashPos >= 0 && (questionPos < 0 || questionPos > hashPos))
+        pathEnd = hashPos;
+    else if (questionPos >= 0)
+        pathEnd = questionPos;
+    else
+        pathEnd = string.length();
+
+    return string.left(pathEnd).replace('\\','/') + string.substring(pathEnd);
+}
+
+bool KURL::isHierarchical() const
+{
+    if (!m_isValid)
+        return false;
+    ASSERT(m_string[m_schemeEnd] == ':');
+    return m_string[m_schemeEnd + 1] == '/';
+}
+
+void KURL::copyToBuffer(CharBuffer& buffer) const
+{
+    // FIXME: This throws away the high bytes of all the characters in the string!
+    // That's fine for a valid URL, which is all ASCII, but not for invalid URLs.
+    buffer.resize(m_string.length());
+    copyASCII(m_string.characters(), m_string.length(), buffer.data());
+}
+
+bool protocolIs(const String& url, const char* protocol)
+{
+    // Do the comparison without making a new string object.
+    assertProtocolIsGood(protocol);
+    for (int i = 0; ; ++i) {
+        if (!protocol[i])
+            return url[i] == ':';
+        if (toASCIILower(url[i]) != protocol[i])
+            return false;
+    }
+}
+
+bool protocolIsJavaScript(const String& url)
+{
+    return protocolIs(url, "javascript");
+}
+
+bool isValidProtocol(const String& protocol)
+{
+    // RFC3986: ALPHA *( ALPHA / DIGIT / "+" / "-" / "." )
+    if (protocol.isEmpty())
+        return false;
+    if (!isSchemeFirstChar(protocol[0]))
+        return false;
+    unsigned protocolLength = protocol.length();
+    for (unsigned i = 1; i < protocolLength; i++) {
+        if (!isSchemeChar(protocol[i]))
+            return false;
+    }
+    return true;
+}
+
+bool isDefaultPortForProtocol(unsigned short port, const String& protocol)
+{
+    if (protocol.isEmpty())
+        return false;
+
+    typedef HashMap<String, unsigned, CaseFoldingHash> DefaultPortsMap;
+    DEFINE_STATIC_LOCAL(DefaultPortsMap, defaultPorts, ());
+    if (defaultPorts.isEmpty()) {
+        defaultPorts.set("http", 80);
+        defaultPorts.set("https", 443);
+        defaultPorts.set("ftp", 21);
+        defaultPorts.set("ftps", 990);
+    }
+    return defaultPorts.get(protocol) == port;
+}
+
+bool portAllowed(const KURL& url)
+{
+    unsigned short port = url.port();
+
+    // Since most URLs don't have a port, return early for the "no port" case.
+    if (!port)
+        return true;
+
+    // This blocked port list matches the port blocking that Mozilla implements.
+    // See http://www.mozilla.org/projects/netlib/PortBanning.html for more information.
+    static const unsigned short blockedPortList[] = {
+        1,    // tcpmux
+        7,    // echo
+        9,    // discard
+        11,   // systat
+        13,   // daytime
+        15,   // netstat
+        17,   // qotd
+        19,   // chargen
+        20,   // FTP-data
+        21,   // FTP-control
+        22,   // SSH
+        23,   // telnet
+        25,   // SMTP
+        37,   // time
+        42,   // name
+        43,   // nicname
+        53,   // domain
+        77,   // priv-rjs
+        79,   // finger
+        87,   // ttylink
+        95,   // supdup
+        101,  // hostriame
+        102,  // iso-tsap
+        103,  // gppitnp
+        104,  // acr-nema
+        109,  // POP2
+        110,  // POP3
+        111,  // sunrpc
+        113,  // auth
+        115,  // SFTP
+        117,  // uucp-path
+        119,  // nntp
+        123,  // NTP
+        135,  // loc-srv / epmap
+        139,  // netbios
+        143,  // IMAP2
+        179,  // BGP
+        389,  // LDAP
+        465,  // SMTP+SSL
+        512,  // print / exec
+        513,  // login
+        514,  // shell
+        515,  // printer
+        526,  // tempo
+        530,  // courier
+        531,  // Chat
+        532,  // netnews
+        540,  // UUCP
+        556,  // remotefs
+        563,  // NNTP+SSL
+        587,  // ESMTP
+        601,  // syslog-conn
+        636,  // LDAP+SSL
+        993,  // IMAP+SSL
+        995,  // POP3+SSL
+        2049, // NFS
+        3659, // apple-sasl / PasswordServer [Apple addition]
+        4045, // lockd
+        6000, // X11
+        6665, // Alternate IRC [Apple addition]
+        6666, // Alternate IRC [Apple addition]
+        6667, // Standard IRC [Apple addition]
+        6668, // Alternate IRC [Apple addition]
+        6669, // Alternate IRC [Apple addition]
+        invalidPortNumber, // Used to block all invalid port numbers
+    };
+    const unsigned short* const blockedPortListEnd = blockedPortList + sizeof(blockedPortList) / sizeof(blockedPortList[0]);
+
+#ifndef NDEBUG
+    // The port list must be sorted for binary_search to work.
+    static bool checkedPortList = false;
+    if (!checkedPortList) {
+        for (const unsigned short* p = blockedPortList; p != blockedPortListEnd - 1; ++p)
+            ASSERT(*p < *(p + 1));
+        checkedPortList = true;
+    }
+#endif
+
+    // If the port is not in the blocked port list, allow it.
+    if (!binary_search(blockedPortList, blockedPortListEnd, port))
+        return true;
+
+    // Allow ports 21 and 22 for FTP URLs, as Mozilla does.
+    if ((port == 21 || port == 22) && url.protocolIs("ftp"))
+        return true;
+
+    // Allow any port number in a file URL, since the port number is ignored.
+    if (url.protocolIs("file"))
+        return true;
+
+    return false;
+}
+
+String mimeTypeFromDataURL(const String& url)
+{
+    ASSERT(protocolIs(url, "data"));
+    int index = url.find(';');
+    if (index == -1)
+        index = url.find(',');
+    if (index != -1) {
+        int len = index - 5;
+        if (len > 0)
+            return url.substring(5, len);
+        return "text/plain"; // Data URLs with no MIME type are considered text/plain.
+    }
+    return "";
+}
+
+const KURL& blankURL()
+{
+    DEFINE_STATIC_LOCAL(KURL, staticBlankURL, (ParsedURLString, "about:blank"));
+    return staticBlankURL;
+}
+
+#ifndef NDEBUG
+void KURL::print() const
+{
+    printf("%s\n", m_string.utf8().data());
+}
+#endif
+
+}
+
+#endif  // !USE(GOOGLEURL)