deps/v8/src/uri.h
// Copyright 2013 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef V8_URI_H_
#define V8_URI_H_
#include "src/v8.h"
#include "src/conversions.h"
#include "src/string-search.h"
#include "src/utils.h"
namespace v8 {
namespace internal {
template <typename Char>
static INLINE(Vector<const Char> GetCharVector(Handle<String> string));
template <>
Vector<const uint8_t> GetCharVector(Handle<String> string) {
String::FlatContent flat = string->GetFlatContent();
DCHECK(flat.IsAscii());
return flat.ToOneByteVector();
}
template <>
Vector<const uc16> GetCharVector(Handle<String> string) {
String::FlatContent flat = string->GetFlatContent();
DCHECK(flat.IsTwoByte());
return flat.ToUC16Vector();
}
class URIUnescape : public AllStatic {
public:
template<typename Char>
MUST_USE_RESULT static MaybeHandle<String> Unescape(Isolate* isolate,
Handle<String> source);
private:
static const signed char kHexValue['g'];
template<typename Char>
MUST_USE_RESULT static MaybeHandle<String> UnescapeSlow(
Isolate* isolate, Handle<String> string, int start_index);
static INLINE(int TwoDigitHex(uint16_t character1, uint16_t character2));
template <typename Char>
static INLINE(int UnescapeChar(Vector<const Char> vector,
int i,
int length,
int* step));
};
const signed char URIUnescape::kHexValue[] = {
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-0, 1, 2, 3, 4, 5, 6, 7, 8, 9, -1, -1, -1, -1, -1, -1,
-1, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, 10, 11, 12, 13, 14, 15 };
template<typename Char>
MaybeHandle<String> URIUnescape::Unescape(Isolate* isolate,
Handle<String> source) {
int index;
{ DisallowHeapAllocation no_allocation;
StringSearch<uint8_t, Char> search(isolate, STATIC_ASCII_VECTOR("%"));
index = search.Search(GetCharVector<Char>(source), 0);
if (index < 0) return source;
}
return UnescapeSlow<Char>(isolate, source, index);
}
template <typename Char>
MaybeHandle<String> URIUnescape::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 = GetCharVector<Char>(string);
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 = GetCharVector<Char>(string);
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 = GetCharVector<Char>(string);
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);
}
int URIUnescape::TwoDigitHex(uint16_t character1, uint16_t character2) {
if (character1 > 'f') return -1;
int hi = kHexValue[character1];
if (hi == -1) return -1;
if (character2 > 'f') return -1;
int lo = kHexValue[character2];
if (lo == -1) return -1;
return (hi << 4) + lo;
}
template <typename Char>
int URIUnescape::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;
}
}
class URIEscape : public AllStatic {
public:
template<typename Char>
MUST_USE_RESULT static MaybeHandle<String> Escape(Isolate* isolate,
Handle<String> string);
private:
static const char kHexChars[17];
static const char kNotEscaped[256];
static bool IsNotEscaped(uint16_t c) { return kNotEscaped[c] != 0; }
};
const char URIEscape::kHexChars[] = "0123456789ABCDEF";
// kNotEscaped is generated by the following:
//
// #!/bin/perl
// for (my $i = 0; $i < 256; $i++) {
// print "\n" if $i % 16 == 0;
// my $c = chr($i);
// my $escaped = 1;
// $escaped = 0 if $c =~ m#[A-Za-z0-9@*_+./-]#;
// print $escaped ? "0, " : "1, ";
// }
const char URIEscape::kNotEscaped[] = {
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 1,
0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
template<typename Char>
MaybeHandle<String> URIEscape::Escape(Isolate* isolate, Handle<String> string) {
DCHECK(string->IsFlat());
int escaped_length = 0;
int length = string->length();
{ DisallowHeapAllocation no_allocation;
Vector<const Char> vector = GetCharVector<Char>(string);
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 = GetCharVector<Char>(string);
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, kHexChars[c >> 12]);
dest->SeqOneByteStringSet(dest_position+3, kHexChars[(c >> 8) & 0xf]);
dest->SeqOneByteStringSet(dest_position+4, kHexChars[(c >> 4) & 0xf]);
dest->SeqOneByteStringSet(dest_position+5, kHexChars[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, kHexChars[c >> 4]);
dest->SeqOneByteStringSet(dest_position+2, kHexChars[c & 0xf]);
dest_position += 3;
}
}
}
return dest;
}
} } // namespace v8::internal
#endif // V8_URI_H_