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-rw-r--r--security/sandbox/chromium/base/strings/string_number_conversions.cc485
1 files changed, 485 insertions, 0 deletions
diff --git a/security/sandbox/chromium/base/strings/string_number_conversions.cc b/security/sandbox/chromium/base/strings/string_number_conversions.cc
new file mode 100644
index 000000000..07248501e
--- /dev/null
+++ b/security/sandbox/chromium/base/strings/string_number_conversions.cc
@@ -0,0 +1,485 @@
+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "base/strings/string_number_conversions.h"
+
+#include <ctype.h>
+#include <errno.h>
+#include <stdlib.h>
+#include <wctype.h>
+
+#include <limits>
+
+#include "base/logging.h"
+#include "base/numerics/safe_conversions.h"
+#include "base/numerics/safe_math.h"
+#include "base/scoped_clear_errno.h"
+#include "base/strings/utf_string_conversions.h"
+#include "base/third_party/dmg_fp/dmg_fp.h"
+
+namespace base {
+
+namespace {
+
+template <typename STR, typename INT>
+struct IntToStringT {
+ static STR IntToString(INT value) {
+ // log10(2) ~= 0.3 bytes needed per bit or per byte log10(2**8) ~= 2.4.
+ // So round up to allocate 3 output characters per byte, plus 1 for '-'.
+ const size_t kOutputBufSize =
+ 3 * sizeof(INT) + std::numeric_limits<INT>::is_signed;
+
+ // Create the string in a temporary buffer, write it back to front, and
+ // then return the substr of what we ended up using.
+ using CHR = typename STR::value_type;
+ CHR outbuf[kOutputBufSize];
+
+ // The ValueOrDie call below can never fail, because UnsignedAbs is valid
+ // for all valid inputs.
+ auto res = CheckedNumeric<INT>(value).UnsignedAbs().ValueOrDie();
+
+ CHR* end = outbuf + kOutputBufSize;
+ CHR* i = end;
+ do {
+ --i;
+ DCHECK(i != outbuf);
+ *i = static_cast<CHR>((res % 10) + '0');
+ res /= 10;
+ } while (res != 0);
+ if (IsValueNegative(value)) {
+ --i;
+ DCHECK(i != outbuf);
+ *i = static_cast<CHR>('-');
+ }
+ return STR(i, end);
+ }
+};
+
+// Utility to convert a character to a digit in a given base
+template<typename CHAR, int BASE, bool BASE_LTE_10> class BaseCharToDigit {
+};
+
+// Faster specialization for bases <= 10
+template<typename CHAR, int BASE> class BaseCharToDigit<CHAR, BASE, true> {
+ public:
+ static bool Convert(CHAR c, uint8_t* digit) {
+ if (c >= '0' && c < '0' + BASE) {
+ *digit = static_cast<uint8_t>(c - '0');
+ return true;
+ }
+ return false;
+ }
+};
+
+// Specialization for bases where 10 < base <= 36
+template<typename CHAR, int BASE> class BaseCharToDigit<CHAR, BASE, false> {
+ public:
+ static bool Convert(CHAR c, uint8_t* digit) {
+ if (c >= '0' && c <= '9') {
+ *digit = c - '0';
+ } else if (c >= 'a' && c < 'a' + BASE - 10) {
+ *digit = c - 'a' + 10;
+ } else if (c >= 'A' && c < 'A' + BASE - 10) {
+ *digit = c - 'A' + 10;
+ } else {
+ return false;
+ }
+ return true;
+ }
+};
+
+template <int BASE, typename CHAR>
+bool CharToDigit(CHAR c, uint8_t* digit) {
+ return BaseCharToDigit<CHAR, BASE, BASE <= 10>::Convert(c, digit);
+}
+
+// There is an IsUnicodeWhitespace for wchars defined in string_util.h, but it
+// is locale independent, whereas the functions we are replacing were
+// locale-dependent. TBD what is desired, but for the moment let's not
+// introduce a change in behaviour.
+template<typename CHAR> class WhitespaceHelper {
+};
+
+template<> class WhitespaceHelper<char> {
+ public:
+ static bool Invoke(char c) {
+ return 0 != isspace(static_cast<unsigned char>(c));
+ }
+};
+
+template<> class WhitespaceHelper<char16> {
+ public:
+ static bool Invoke(char16 c) {
+ return 0 != iswspace(c);
+ }
+};
+
+template<typename CHAR> bool LocalIsWhitespace(CHAR c) {
+ return WhitespaceHelper<CHAR>::Invoke(c);
+}
+
+// IteratorRangeToNumberTraits should provide:
+// - a typedef for iterator_type, the iterator type used as input.
+// - a typedef for value_type, the target numeric type.
+// - static functions min, max (returning the minimum and maximum permitted
+// values)
+// - constant kBase, the base in which to interpret the input
+template<typename IteratorRangeToNumberTraits>
+class IteratorRangeToNumber {
+ public:
+ typedef IteratorRangeToNumberTraits traits;
+ typedef typename traits::iterator_type const_iterator;
+ typedef typename traits::value_type value_type;
+
+ // Generalized iterator-range-to-number conversion.
+ //
+ static bool Invoke(const_iterator begin,
+ const_iterator end,
+ value_type* output) {
+ bool valid = true;
+
+ while (begin != end && LocalIsWhitespace(*begin)) {
+ valid = false;
+ ++begin;
+ }
+
+ if (begin != end && *begin == '-') {
+ if (!std::numeric_limits<value_type>::is_signed) {
+ valid = false;
+ } else if (!Negative::Invoke(begin + 1, end, output)) {
+ valid = false;
+ }
+ } else {
+ if (begin != end && *begin == '+') {
+ ++begin;
+ }
+ if (!Positive::Invoke(begin, end, output)) {
+ valid = false;
+ }
+ }
+
+ return valid;
+ }
+
+ private:
+ // Sign provides:
+ // - a static function, CheckBounds, that determines whether the next digit
+ // causes an overflow/underflow
+ // - a static function, Increment, that appends the next digit appropriately
+ // according to the sign of the number being parsed.
+ template<typename Sign>
+ class Base {
+ public:
+ static bool Invoke(const_iterator begin, const_iterator end,
+ typename traits::value_type* output) {
+ *output = 0;
+
+ if (begin == end) {
+ return false;
+ }
+
+ // Note: no performance difference was found when using template
+ // specialization to remove this check in bases other than 16
+ if (traits::kBase == 16 && end - begin > 2 && *begin == '0' &&
+ (*(begin + 1) == 'x' || *(begin + 1) == 'X')) {
+ begin += 2;
+ }
+
+ for (const_iterator current = begin; current != end; ++current) {
+ uint8_t new_digit = 0;
+
+ if (!CharToDigit<traits::kBase>(*current, &new_digit)) {
+ return false;
+ }
+
+ if (current != begin) {
+ if (!Sign::CheckBounds(output, new_digit)) {
+ return false;
+ }
+ *output *= traits::kBase;
+ }
+
+ Sign::Increment(new_digit, output);
+ }
+ return true;
+ }
+ };
+
+ class Positive : public Base<Positive> {
+ public:
+ static bool CheckBounds(value_type* output, uint8_t new_digit) {
+ if (*output > static_cast<value_type>(traits::max() / traits::kBase) ||
+ (*output == static_cast<value_type>(traits::max() / traits::kBase) &&
+ new_digit > traits::max() % traits::kBase)) {
+ *output = traits::max();
+ return false;
+ }
+ return true;
+ }
+ static void Increment(uint8_t increment, value_type* output) {
+ *output += increment;
+ }
+ };
+
+ class Negative : public Base<Negative> {
+ public:
+ static bool CheckBounds(value_type* output, uint8_t new_digit) {
+ if (*output < traits::min() / traits::kBase ||
+ (*output == traits::min() / traits::kBase &&
+ new_digit > 0 - traits::min() % traits::kBase)) {
+ *output = traits::min();
+ return false;
+ }
+ return true;
+ }
+ static void Increment(uint8_t increment, value_type* output) {
+ *output -= increment;
+ }
+ };
+};
+
+template<typename ITERATOR, typename VALUE, int BASE>
+class BaseIteratorRangeToNumberTraits {
+ public:
+ typedef ITERATOR iterator_type;
+ typedef VALUE value_type;
+ static value_type min() {
+ return std::numeric_limits<value_type>::min();
+ }
+ static value_type max() {
+ return std::numeric_limits<value_type>::max();
+ }
+ static const int kBase = BASE;
+};
+
+template<typename ITERATOR>
+class BaseHexIteratorRangeToIntTraits
+ : public BaseIteratorRangeToNumberTraits<ITERATOR, int, 16> {
+};
+
+template <typename ITERATOR>
+class BaseHexIteratorRangeToUIntTraits
+ : public BaseIteratorRangeToNumberTraits<ITERATOR, uint32_t, 16> {};
+
+template <typename ITERATOR>
+class BaseHexIteratorRangeToInt64Traits
+ : public BaseIteratorRangeToNumberTraits<ITERATOR, int64_t, 16> {};
+
+template <typename ITERATOR>
+class BaseHexIteratorRangeToUInt64Traits
+ : public BaseIteratorRangeToNumberTraits<ITERATOR, uint64_t, 16> {};
+
+typedef BaseHexIteratorRangeToIntTraits<StringPiece::const_iterator>
+ HexIteratorRangeToIntTraits;
+
+typedef BaseHexIteratorRangeToUIntTraits<StringPiece::const_iterator>
+ HexIteratorRangeToUIntTraits;
+
+typedef BaseHexIteratorRangeToInt64Traits<StringPiece::const_iterator>
+ HexIteratorRangeToInt64Traits;
+
+typedef BaseHexIteratorRangeToUInt64Traits<StringPiece::const_iterator>
+ HexIteratorRangeToUInt64Traits;
+
+template <typename STR>
+bool HexStringToBytesT(const STR& input, std::vector<uint8_t>* output) {
+ DCHECK_EQ(output->size(), 0u);
+ size_t count = input.size();
+ if (count == 0 || (count % 2) != 0)
+ return false;
+ for (uintptr_t i = 0; i < count / 2; ++i) {
+ uint8_t msb = 0; // most significant 4 bits
+ uint8_t lsb = 0; // least significant 4 bits
+ if (!CharToDigit<16>(input[i * 2], &msb) ||
+ !CharToDigit<16>(input[i * 2 + 1], &lsb))
+ return false;
+ output->push_back((msb << 4) | lsb);
+ }
+ return true;
+}
+
+template <typename VALUE, int BASE>
+class StringPieceToNumberTraits
+ : public BaseIteratorRangeToNumberTraits<StringPiece::const_iterator,
+ VALUE,
+ BASE> {
+};
+
+template <typename VALUE>
+bool StringToIntImpl(const StringPiece& input, VALUE* output) {
+ return IteratorRangeToNumber<StringPieceToNumberTraits<VALUE, 10> >::Invoke(
+ input.begin(), input.end(), output);
+}
+
+template <typename VALUE, int BASE>
+class StringPiece16ToNumberTraits
+ : public BaseIteratorRangeToNumberTraits<StringPiece16::const_iterator,
+ VALUE,
+ BASE> {
+};
+
+template <typename VALUE>
+bool String16ToIntImpl(const StringPiece16& input, VALUE* output) {
+ return IteratorRangeToNumber<StringPiece16ToNumberTraits<VALUE, 10> >::Invoke(
+ input.begin(), input.end(), output);
+}
+
+} // namespace
+
+std::string IntToString(int value) {
+ return IntToStringT<std::string, int>::IntToString(value);
+}
+
+string16 IntToString16(int value) {
+ return IntToStringT<string16, int>::IntToString(value);
+}
+
+std::string UintToString(unsigned int value) {
+ return IntToStringT<std::string, unsigned int>::IntToString(value);
+}
+
+string16 UintToString16(unsigned int value) {
+ return IntToStringT<string16, unsigned int>::IntToString(value);
+}
+
+std::string Int64ToString(int64_t value) {
+ return IntToStringT<std::string, int64_t>::IntToString(value);
+}
+
+string16 Int64ToString16(int64_t value) {
+ return IntToStringT<string16, int64_t>::IntToString(value);
+}
+
+std::string Uint64ToString(uint64_t value) {
+ return IntToStringT<std::string, uint64_t>::IntToString(value);
+}
+
+string16 Uint64ToString16(uint64_t value) {
+ return IntToStringT<string16, uint64_t>::IntToString(value);
+}
+
+std::string SizeTToString(size_t value) {
+ return IntToStringT<std::string, size_t>::IntToString(value);
+}
+
+string16 SizeTToString16(size_t value) {
+ return IntToStringT<string16, size_t>::IntToString(value);
+}
+
+std::string DoubleToString(double value) {
+ // According to g_fmt.cc, it is sufficient to declare a buffer of size 32.
+ char buffer[32];
+ dmg_fp::g_fmt(buffer, value);
+ return std::string(buffer);
+}
+
+bool StringToInt(const StringPiece& input, int* output) {
+ return StringToIntImpl(input, output);
+}
+
+bool StringToInt(const StringPiece16& input, int* output) {
+ return String16ToIntImpl(input, output);
+}
+
+bool StringToUint(const StringPiece& input, unsigned* output) {
+ return StringToIntImpl(input, output);
+}
+
+bool StringToUint(const StringPiece16& input, unsigned* output) {
+ return String16ToIntImpl(input, output);
+}
+
+bool StringToInt64(const StringPiece& input, int64_t* output) {
+ return StringToIntImpl(input, output);
+}
+
+bool StringToInt64(const StringPiece16& input, int64_t* output) {
+ return String16ToIntImpl(input, output);
+}
+
+bool StringToUint64(const StringPiece& input, uint64_t* output) {
+ return StringToIntImpl(input, output);
+}
+
+bool StringToUint64(const StringPiece16& input, uint64_t* output) {
+ return String16ToIntImpl(input, output);
+}
+
+bool StringToSizeT(const StringPiece& input, size_t* output) {
+ return StringToIntImpl(input, output);
+}
+
+bool StringToSizeT(const StringPiece16& input, size_t* output) {
+ return String16ToIntImpl(input, output);
+}
+
+bool StringToDouble(const std::string& input, double* output) {
+ // Thread-safe? It is on at least Mac, Linux, and Windows.
+ ScopedClearErrno clear_errno;
+
+ char* endptr = NULL;
+ *output = dmg_fp::strtod(input.c_str(), &endptr);
+
+ // Cases to return false:
+ // - If errno is ERANGE, there was an overflow or underflow.
+ // - If the input string is empty, there was nothing to parse.
+ // - If endptr does not point to the end of the string, there are either
+ // characters remaining in the string after a parsed number, or the string
+ // does not begin with a parseable number. endptr is compared to the
+ // expected end given the string's stated length to correctly catch cases
+ // where the string contains embedded NUL characters.
+ // - If the first character is a space, there was leading whitespace
+ return errno == 0 &&
+ !input.empty() &&
+ input.c_str() + input.length() == endptr &&
+ !isspace(input[0]);
+}
+
+// Note: if you need to add String16ToDouble, first ask yourself if it's
+// really necessary. If it is, probably the best implementation here is to
+// convert to 8-bit and then use the 8-bit version.
+
+// Note: if you need to add an iterator range version of StringToDouble, first
+// ask yourself if it's really necessary. If it is, probably the best
+// implementation here is to instantiate a string and use the string version.
+
+std::string HexEncode(const void* bytes, size_t size) {
+ static const char kHexChars[] = "0123456789ABCDEF";
+
+ // Each input byte creates two output hex characters.
+ std::string ret(size * 2, '\0');
+
+ for (size_t i = 0; i < size; ++i) {
+ char b = reinterpret_cast<const char*>(bytes)[i];
+ ret[(i * 2)] = kHexChars[(b >> 4) & 0xf];
+ ret[(i * 2) + 1] = kHexChars[b & 0xf];
+ }
+ return ret;
+}
+
+bool HexStringToInt(const StringPiece& input, int* output) {
+ return IteratorRangeToNumber<HexIteratorRangeToIntTraits>::Invoke(
+ input.begin(), input.end(), output);
+}
+
+bool HexStringToUInt(const StringPiece& input, uint32_t* output) {
+ return IteratorRangeToNumber<HexIteratorRangeToUIntTraits>::Invoke(
+ input.begin(), input.end(), output);
+}
+
+bool HexStringToInt64(const StringPiece& input, int64_t* output) {
+ return IteratorRangeToNumber<HexIteratorRangeToInt64Traits>::Invoke(
+ input.begin(), input.end(), output);
+}
+
+bool HexStringToUInt64(const StringPiece& input, uint64_t* output) {
+ return IteratorRangeToNumber<HexIteratorRangeToUInt64Traits>::Invoke(
+ input.begin(), input.end(), output);
+}
+
+bool HexStringToBytes(const std::string& input, std::vector<uint8_t>* output) {
+ return HexStringToBytesT(input, output);
+}
+
+} // namespace base