Merge V8 5.3.332.45.  DO NOT MERGE

Test: Manual

FPIIM-449

Change-Id: Id3254828b068abdea3cb10442e0172a8c9a98e03
(cherry picked from commit 13e2dadd00298019ed862f2b2fc5068bba730bcf)
diff --git a/src/uri.cc b/src/uri.cc
index c459be5..0107721 100644
--- a/src/uri.cc
+++ b/src/uri.cc
@@ -8,10 +8,197 @@
 #include "src/handles.h"
 #include "src/isolate-inl.h"
 #include "src/list.h"
+#include "src/string-search.h"
 
 namespace v8 {
 namespace internal {
 
+namespace {  // anonymous namespace for DecodeURI helper functions
+bool IsReservedPredicate(uc16 c) {
+  switch (c) {
+    case '#':
+    case '$':
+    case '&':
+    case '+':
+    case ',':
+    case '/':
+    case ':':
+    case ';':
+    case '=':
+    case '?':
+    case '@':
+      return true;
+    default:
+      return false;
+  }
+}
+
+bool IsReplacementCharacter(const uint8_t* octets, int length) {
+  // The replacement character is at codepoint U+FFFD in the Unicode Specials
+  // table. Its UTF-8 encoding is 0xEF 0xBF 0xBD.
+  if (length != 3 || octets[0] != 0xef || octets[1] != 0xbf ||
+      octets[2] != 0xbd) {
+    return false;
+  }
+  return true;
+}
+
+bool DecodeOctets(const uint8_t* octets, int length, List<uc16>* buffer) {
+  size_t cursor = 0;
+  uc32 value = unibrow::Utf8::ValueOf(octets, length, &cursor);
+  if (value == unibrow::Utf8::kBadChar &&
+      !IsReplacementCharacter(octets, length)) {
+    return false;
+  }
+
+  if (value <= unibrow::Utf16::kMaxNonSurrogateCharCode) {
+    buffer->Add(value);
+  } else {
+    buffer->Add(unibrow::Utf16::LeadSurrogate(value));
+    buffer->Add(unibrow::Utf16::TrailSurrogate(value));
+  }
+  return true;
+}
+
+int TwoDigitHex(uc16 character1, uc16 character2) {
+  if (character1 > 'f') return -1;
+  int high = HexValue(character1);
+  if (high == -1) return -1;
+  if (character2 > 'f') return -1;
+  int low = HexValue(character2);
+  if (low == -1) return -1;
+  return (high << 4) + low;
+}
+
+template <typename T>
+void AddToBuffer(uc16 decoded, String::FlatContent* uri_content, int index,
+                 bool is_uri, List<T>* buffer) {
+  if (is_uri && IsReservedPredicate(decoded)) {
+    buffer->Add('%');
+    uc16 first = uri_content->Get(index + 1);
+    uc16 second = uri_content->Get(index + 2);
+    DCHECK_GT(std::numeric_limits<T>::max(), first);
+    DCHECK_GT(std::numeric_limits<T>::max(), second);
+
+    buffer->Add(first);
+    buffer->Add(second);
+  } else {
+    buffer->Add(decoded);
+  }
+}
+
+bool IntoTwoByte(int index, bool is_uri, int uri_length,
+                 String::FlatContent* uri_content, List<uc16>* buffer) {
+  for (int k = index; k < uri_length; k++) {
+    uc16 code = uri_content->Get(k);
+    if (code == '%') {
+      uc16 decoded;
+      if (k + 2 >= uri_length ||
+          (decoded = TwoDigitHex(uri_content->Get(k + 1),
+                                 uri_content->Get(k + 2))) < 0) {
+        return false;
+      }
+      k += 2;
+      if (decoded > unibrow::Utf8::kMaxOneByteChar) {
+        uint8_t octets[unibrow::Utf8::kMaxEncodedSize];
+        octets[0] = decoded;
+
+        int number_of_continuation_bytes = 0;
+        while ((decoded << ++number_of_continuation_bytes) & 0x80) {
+          if (number_of_continuation_bytes > 3 || k + 3 >= uri_length) {
+            return false;
+          }
+
+          uc16 continuation_byte;
+
+          if (uri_content->Get(++k) != '%' ||
+              (continuation_byte = TwoDigitHex(uri_content->Get(k + 1),
+                                               uri_content->Get(k + 2))) < 0) {
+            return false;
+          }
+          k += 2;
+          octets[number_of_continuation_bytes] = continuation_byte;
+        }
+
+        if (!DecodeOctets(octets, number_of_continuation_bytes, buffer)) {
+          return false;
+        }
+      } else {
+        AddToBuffer(decoded, uri_content, k - 2, is_uri, buffer);
+      }
+    } else {
+      buffer->Add(code);
+    }
+  }
+  return true;
+}
+
+bool IntoOneAndTwoByte(Handle<String> uri, bool is_uri,
+                       List<uint8_t>* one_byte_buffer,
+                       List<uc16>* two_byte_buffer) {
+  DisallowHeapAllocation no_gc;
+  String::FlatContent uri_content = uri->GetFlatContent();
+
+  int uri_length = uri->length();
+  for (int k = 0; k < uri_length; k++) {
+    uc16 code = uri_content.Get(k);
+    if (code == '%') {
+      uc16 decoded;
+      if (k + 2 >= uri_length ||
+          (decoded = TwoDigitHex(uri_content.Get(k + 1),
+                                 uri_content.Get(k + 2))) < 0) {
+        return false;
+      }
+
+      if (decoded > unibrow::Utf8::kMaxOneByteChar) {
+        return IntoTwoByte(k, is_uri, uri_length, &uri_content,
+                           two_byte_buffer);
+      }
+
+      AddToBuffer(decoded, &uri_content, k, is_uri, one_byte_buffer);
+      k += 2;
+    } else {
+      if (code > unibrow::Utf8::kMaxOneByteChar) {
+        return IntoTwoByte(k, is_uri, uri_length, &uri_content,
+                           two_byte_buffer);
+      }
+      one_byte_buffer->Add(code);
+    }
+  }
+  return true;
+}
+
+}  // anonymous namespace
+
+MaybeHandle<String> Uri::Decode(Isolate* isolate, Handle<String> uri,
+                                bool is_uri) {
+  uri = String::Flatten(uri);
+  List<uint8_t> one_byte_buffer;
+  List<uc16> two_byte_buffer;
+
+  if (!IntoOneAndTwoByte(uri, is_uri, &one_byte_buffer, &two_byte_buffer)) {
+    THROW_NEW_ERROR(isolate, NewURIError(), String);
+  }
+
+  if (two_byte_buffer.is_empty()) {
+    return isolate->factory()->NewStringFromOneByte(
+        one_byte_buffer.ToConstVector());
+  }
+
+  Handle<SeqTwoByteString> result;
+  ASSIGN_RETURN_ON_EXCEPTION(
+      isolate, result, isolate->factory()->NewRawTwoByteString(
+                           one_byte_buffer.length() + two_byte_buffer.length()),
+      String);
+
+  CopyChars(result->GetChars(), one_byte_buffer.ToConstVector().start(),
+            one_byte_buffer.length());
+  CopyChars(result->GetChars() + one_byte_buffer.length(),
+            two_byte_buffer.ToConstVector().start(), two_byte_buffer.length());
+
+  return result;
+}
+
 namespace {  // anonymous namespace for EncodeURI helper functions
 bool IsUnescapePredicateInUriComponent(uc16 c) {
   if (IsAlphaNumeric(c)) {
@@ -53,43 +240,36 @@
   }
 }
 
-void AddHexEncodedToBuffer(uint8_t octet, List<uint8_t>* buffer) {
+void AddEncodedOctetToBuffer(uint8_t octet, List<uint8_t>* buffer) {
   buffer->Add('%');
   buffer->Add(HexCharOfValue(octet >> 4));
   buffer->Add(HexCharOfValue(octet & 0x0F));
 }
 
 void EncodeSingle(uc16 c, List<uint8_t>* buffer) {
-  uint8_t x = (c >> 12) & 0xF;
-  uint8_t y = (c >> 6) & 63;
-  uint8_t z = c & 63;
-  if (c <= 0x007F) {
-    AddHexEncodedToBuffer(c, buffer);
-  } else if (c <= 0x07FF) {
-    AddHexEncodedToBuffer(y + 192, buffer);
-    AddHexEncodedToBuffer(z + 128, buffer);
-  } else {
-    AddHexEncodedToBuffer(x + 224, buffer);
-    AddHexEncodedToBuffer(y + 128, buffer);
-    AddHexEncodedToBuffer(z + 128, buffer);
+  char s[4] = {};
+  int number_of_bytes;
+  number_of_bytes =
+      unibrow::Utf8::Encode(s, c, unibrow::Utf16::kNoPreviousCharacter, false);
+  for (int k = 0; k < number_of_bytes; k++) {
+    AddEncodedOctetToBuffer(s[k], buffer);
   }
 }
 
 void EncodePair(uc16 cc1, uc16 cc2, List<uint8_t>* buffer) {
-  uint8_t u = ((cc1 >> 6) & 0xF) + 1;
-  uint8_t w = (cc1 >> 2) & 0xF;
-  uint8_t x = cc1 & 3;
-  uint8_t y = (cc2 >> 6) & 0xF;
-  uint8_t z = cc2 & 63;
-  AddHexEncodedToBuffer((u >> 2) + 240, buffer);
-  AddHexEncodedToBuffer((((u & 3) << 4) | w) + 128, buffer);
-  AddHexEncodedToBuffer(((x << 4) | y) + 128, buffer);
-  AddHexEncodedToBuffer(z + 128, buffer);
+  char s[4] = {};
+  int number_of_bytes =
+      unibrow::Utf8::Encode(s, unibrow::Utf16::CombineSurrogatePair(cc1, cc2),
+                            unibrow::Utf16::kNoPreviousCharacter, false);
+  for (int k = 0; k < number_of_bytes; k++) {
+    AddEncodedOctetToBuffer(s[k], buffer);
+  }
 }
 
 }  // anonymous namespace
 
-Object* Uri::Encode(Isolate* isolate, Handle<String> uri, bool is_uri) {
+MaybeHandle<String> Uri::Encode(Isolate* isolate, Handle<String> uri,
+                                bool is_uri) {
   uri = String::Flatten(uri);
   int uri_length = uri->length();
   List<uint8_t> buffer(uri_length);
@@ -120,15 +300,205 @@
       }
 
       AllowHeapAllocation allocate_error_and_return;
-      THROW_NEW_ERROR_RETURN_FAILURE(isolate, NewURIError());
+      THROW_NEW_ERROR(isolate, NewURIError(), String);
     }
   }
 
+  return isolate->factory()->NewStringFromOneByte(buffer.ToConstVector());
+}
+
+namespace {  // Anonymous namespace for Escape and Unescape
+
+template <typename Char>
+int UnescapeChar(Vector<const Char> vector, int i, int length, int* step) {
+  uint16_t character = vector[i];
+  int32_t hi = 0;
+  int32_t lo = 0;
+  if (character == '%' && i <= length - 6 && vector[i + 1] == 'u' &&
+      (hi = TwoDigitHex(vector[i + 2], vector[i + 3])) > -1 &&
+      (lo = TwoDigitHex(vector[i + 4], vector[i + 5])) > -1) {
+    *step = 6;
+    return (hi << 8) + lo;
+  } else if (character == '%' && i <= length - 3 &&
+             (lo = TwoDigitHex(vector[i + 1], vector[i + 2])) > -1) {
+    *step = 3;
+    return lo;
+  } else {
+    *step = 1;
+    return character;
+  }
+}
+
+template <typename Char>
+MaybeHandle<String> UnescapeSlow(Isolate* isolate, Handle<String> string,
+                                 int start_index) {
+  bool one_byte = true;
+  int length = string->length();
+
+  int unescaped_length = 0;
+  {
+    DisallowHeapAllocation no_allocation;
+    Vector<const Char> vector = string->GetCharVector<Char>();
+    for (int i = start_index; i < length; unescaped_length++) {
+      int step;
+      if (UnescapeChar(vector, i, length, &step) >
+          String::kMaxOneByteCharCode) {
+        one_byte = false;
+      }
+      i += step;
+    }
+  }
+
+  DCHECK(start_index < length);
+  Handle<String> first_part =
+      isolate->factory()->NewProperSubString(string, 0, start_index);
+
+  int dest_position = 0;
+  Handle<String> second_part;
+  DCHECK(unescaped_length <= String::kMaxLength);
+  if (one_byte) {
+    Handle<SeqOneByteString> dest = isolate->factory()
+                                        ->NewRawOneByteString(unescaped_length)
+                                        .ToHandleChecked();
+    DisallowHeapAllocation no_allocation;
+    Vector<const Char> vector = string->GetCharVector<Char>();
+    for (int i = start_index; i < length; dest_position++) {
+      int step;
+      dest->SeqOneByteStringSet(dest_position,
+                                UnescapeChar(vector, i, length, &step));
+      i += step;
+    }
+    second_part = dest;
+  } else {
+    Handle<SeqTwoByteString> dest = isolate->factory()
+                                        ->NewRawTwoByteString(unescaped_length)
+                                        .ToHandleChecked();
+    DisallowHeapAllocation no_allocation;
+    Vector<const Char> vector = string->GetCharVector<Char>();
+    for (int i = start_index; i < length; dest_position++) {
+      int step;
+      dest->SeqTwoByteStringSet(dest_position,
+                                UnescapeChar(vector, i, length, &step));
+      i += step;
+    }
+    second_part = dest;
+  }
+  return isolate->factory()->NewConsString(first_part, second_part);
+}
+
+bool IsNotEscaped(uint16_t c) {
+  if (IsAlphaNumeric(c)) {
+    return true;
+  }
+  //  @*_+-./
+  switch (c) {
+    case '@':
+    case '*':
+    case '_':
+    case '+':
+    case '-':
+    case '.':
+    case '/':
+      return true;
+    default:
+      return false;
+  }
+}
+
+template <typename Char>
+static MaybeHandle<String> UnescapePrivate(Isolate* isolate,
+                                           Handle<String> source) {
+  int index;
+  {
+    DisallowHeapAllocation no_allocation;
+    StringSearch<uint8_t, Char> search(isolate, STATIC_CHAR_VECTOR("%"));
+    index = search.Search(source->GetCharVector<Char>(), 0);
+    if (index < 0) return source;
+  }
+  return UnescapeSlow<Char>(isolate, source, index);
+}
+
+template <typename Char>
+static MaybeHandle<String> EscapePrivate(Isolate* isolate,
+                                         Handle<String> string) {
+  DCHECK(string->IsFlat());
+  int escaped_length = 0;
+  int length = string->length();
+
+  {
+    DisallowHeapAllocation no_allocation;
+    Vector<const Char> vector = string->GetCharVector<Char>();
+    for (int i = 0; i < length; i++) {
+      uint16_t c = vector[i];
+      if (c >= 256) {
+        escaped_length += 6;
+      } else if (IsNotEscaped(c)) {
+        escaped_length++;
+      } else {
+        escaped_length += 3;
+      }
+
+      // We don't allow strings that are longer than a maximal length.
+      DCHECK(String::kMaxLength < 0x7fffffff - 6);     // Cannot overflow.
+      if (escaped_length > String::kMaxLength) break;  // Provoke exception.
+    }
+  }
+
+  // No length change implies no change.  Return original string if no change.
+  if (escaped_length == length) return string;
+
+  Handle<SeqOneByteString> dest;
+  ASSIGN_RETURN_ON_EXCEPTION(
+      isolate, dest, isolate->factory()->NewRawOneByteString(escaped_length),
+      String);
+  int dest_position = 0;
+
+  {
+    DisallowHeapAllocation no_allocation;
+    Vector<const Char> vector = string->GetCharVector<Char>();
+    for (int i = 0; i < length; i++) {
+      uint16_t c = vector[i];
+      if (c >= 256) {
+        dest->SeqOneByteStringSet(dest_position, '%');
+        dest->SeqOneByteStringSet(dest_position + 1, 'u');
+        dest->SeqOneByteStringSet(dest_position + 2, HexCharOfValue(c >> 12));
+        dest->SeqOneByteStringSet(dest_position + 3,
+                                  HexCharOfValue((c >> 8) & 0xf));
+        dest->SeqOneByteStringSet(dest_position + 4,
+                                  HexCharOfValue((c >> 4) & 0xf));
+        dest->SeqOneByteStringSet(dest_position + 5, HexCharOfValue(c & 0xf));
+        dest_position += 6;
+      } else if (IsNotEscaped(c)) {
+        dest->SeqOneByteStringSet(dest_position, c);
+        dest_position++;
+      } else {
+        dest->SeqOneByteStringSet(dest_position, '%');
+        dest->SeqOneByteStringSet(dest_position + 1, HexCharOfValue(c >> 4));
+        dest->SeqOneByteStringSet(dest_position + 2, HexCharOfValue(c & 0xf));
+        dest_position += 3;
+      }
+    }
+  }
+
+  return dest;
+}
+
+}  // Anonymous namespace
+
+MaybeHandle<String> Uri::Escape(Isolate* isolate, Handle<String> string) {
   Handle<String> result;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-      isolate, result,
-      isolate->factory()->NewStringFromOneByte(buffer.ToConstVector()));
-  return *result;
+  string = String::Flatten(string);
+  return string->IsOneByteRepresentationUnderneath()
+             ? EscapePrivate<uint8_t>(isolate, string)
+             : EscapePrivate<uc16>(isolate, string);
+}
+
+MaybeHandle<String> Uri::Unescape(Isolate* isolate, Handle<String> string) {
+  Handle<String> result;
+  string = String::Flatten(string);
+  return string->IsOneByteRepresentationUnderneath()
+             ? UnescapePrivate<uint8_t>(isolate, string)
+             : UnescapePrivate<uc16>(isolate, string);
 }
 
 }  // namespace internal