Merge pull request #1272 from antonioborondo/fix_warning

Fix warning C4127: conditional expression is constant
This commit is contained in:
Niels Lohmann 2018-10-04 20:33:26 +02:00 committed by GitHub
commit 5c7d27c338
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
2 changed files with 148 additions and 130 deletions

View file

@ -115,38 +115,66 @@ class input_buffer_adapter : public input_adapter_protocol
const char* const limit; const char* const limit;
}; };
template<typename WideStringType> template<typename WideStringType, size_t T>
class wide_string_input_adapter : public input_adapter_protocol struct wide_string_input_helper
{ {
public: // UTF-32
explicit wide_string_input_adapter(const WideStringType& w) : str(w) {} static void fill_buffer(const WideStringType& str, size_t& current_wchar, std::array<std::char_traits<char>::int_type, 4>& utf8_bytes, size_t& utf8_bytes_index, size_t& utf8_bytes_filled)
{
utf8_bytes_index = 0;
std::char_traits<char>::int_type get_character() noexcept override if (current_wchar == str.size())
{ {
// check if buffer needs to be filled utf8_bytes[0] = std::char_traits<char>::eof();
if (utf8_bytes_index == utf8_bytes_filled) utf8_bytes_filled = 1;
{
if (sizeof(typename WideStringType::value_type) == 2)
{
fill_buffer_utf16();
} }
else else
{ {
fill_buffer_utf32(); // get the current character
} const int wc = static_cast<int>(str[current_wchar++]);
assert(utf8_bytes_filled > 0); // UTF-32 to UTF-8 encoding
assert(utf8_bytes_index == 0); if (wc < 0x80)
{
utf8_bytes[0] = wc;
utf8_bytes_filled = 1;
} }
else if (wc <= 0x7FF)
// use buffer {
assert(utf8_bytes_filled > 0); utf8_bytes[0] = 0xC0 | ((wc >> 6) & 0x1F);
assert(utf8_bytes_index < utf8_bytes_filled); utf8_bytes[1] = 0x80 | (wc & 0x3F);
return utf8_bytes[utf8_bytes_index++]; utf8_bytes_filled = 2;
} }
else if (wc <= 0xFFFF)
{
utf8_bytes[0] = 0xE0 | ((wc >> 12) & 0x0F);
utf8_bytes[1] = 0x80 | ((wc >> 6) & 0x3F);
utf8_bytes[2] = 0x80 | (wc & 0x3F);
utf8_bytes_filled = 3;
}
else if (wc <= 0x10FFFF)
{
utf8_bytes[0] = 0xF0 | ((wc >> 18) & 0x07);
utf8_bytes[1] = 0x80 | ((wc >> 12) & 0x3F);
utf8_bytes[2] = 0x80 | ((wc >> 6) & 0x3F);
utf8_bytes[3] = 0x80 | (wc & 0x3F);
utf8_bytes_filled = 4;
}
else
{
// unknown character
utf8_bytes[0] = wc;
utf8_bytes_filled = 1;
}
}
}
};
private: template<typename WideStringType>
void fill_buffer_utf16() struct wide_string_input_helper<WideStringType, 2>
{
// UTF-16
static void fill_buffer(const WideStringType& str, size_t& current_wchar, std::array<std::char_traits<char>::int_type, 4>& utf8_bytes, size_t& utf8_bytes_index, size_t& utf8_bytes_filled)
{ {
utf8_bytes_index = 0; utf8_bytes_index = 0;
@ -201,58 +229,38 @@ class wide_string_input_adapter : public input_adapter_protocol
} }
} }
} }
};
void fill_buffer_utf32() template<typename WideStringType>
{ class wide_string_input_adapter : public input_adapter_protocol
utf8_bytes_index = 0; {
public:
explicit wide_string_input_adapter(const WideStringType& w) : str(w) {}
if (current_wchar == str.size()) std::char_traits<char>::int_type get_character() noexcept override
{ {
utf8_bytes[0] = std::char_traits<char>::eof(); // check if buffer needs to be filled
utf8_bytes_filled = 1; if (utf8_bytes_index == utf8_bytes_filled)
}
else
{ {
// get the current character fill_buffer<sizeof(typename WideStringType::value_type)>();
const int wc = static_cast<int>(str[current_wchar++]);
// UTF-32 to UTF-8 encoding assert(utf8_bytes_filled > 0);
if (wc < 0x80) assert(utf8_bytes_index == 0);
{
utf8_bytes[0] = wc;
utf8_bytes_filled = 1;
}
else if (wc <= 0x7FF)
{
utf8_bytes[0] = 0xC0 | ((wc >> 6) & 0x1F);
utf8_bytes[1] = 0x80 | (wc & 0x3F);
utf8_bytes_filled = 2;
}
else if (wc <= 0xFFFF)
{
utf8_bytes[0] = 0xE0 | ((wc >> 12) & 0x0F);
utf8_bytes[1] = 0x80 | ((wc >> 6) & 0x3F);
utf8_bytes[2] = 0x80 | (wc & 0x3F);
utf8_bytes_filled = 3;
}
else if (wc <= 0x10FFFF)
{
utf8_bytes[0] = 0xF0 | ((wc >> 18 ) & 0x07);
utf8_bytes[1] = 0x80 | ((wc >> 12) & 0x3F);
utf8_bytes[2] = 0x80 | ((wc >> 6) & 0x3F);
utf8_bytes[3] = 0x80 | (wc & 0x3F);
utf8_bytes_filled = 4;
}
else
{
// unknown character
utf8_bytes[0] = wc;
utf8_bytes_filled = 1;
}
} }
// use buffer
assert(utf8_bytes_filled > 0);
assert(utf8_bytes_index < utf8_bytes_filled);
return utf8_bytes[utf8_bytes_index++];
} }
private: private:
template<size_t T>
void fill_buffer()
{
wide_string_input_helper<WideStringType, T>::fill_buffer(str, current_wchar, utf8_bytes, utf8_bytes_index, utf8_bytes_filled);
}
/// the wstring to process /// the wstring to process
const WideStringType& str; const WideStringType& str;

View file

@ -1993,38 +1993,66 @@ class input_buffer_adapter : public input_adapter_protocol
const char* const limit; const char* const limit;
}; };
template<typename WideStringType> template<typename WideStringType, size_t T>
class wide_string_input_adapter : public input_adapter_protocol struct wide_string_input_helper
{ {
public: // UTF-32
explicit wide_string_input_adapter(const WideStringType& w) : str(w) {} static void fill_buffer(const WideStringType& str, size_t& current_wchar, std::array<std::char_traits<char>::int_type, 4>& utf8_bytes, size_t& utf8_bytes_index, size_t& utf8_bytes_filled)
{
utf8_bytes_index = 0;
std::char_traits<char>::int_type get_character() noexcept override if (current_wchar == str.size())
{ {
// check if buffer needs to be filled utf8_bytes[0] = std::char_traits<char>::eof();
if (utf8_bytes_index == utf8_bytes_filled) utf8_bytes_filled = 1;
{
if (sizeof(typename WideStringType::value_type) == 2)
{
fill_buffer_utf16();
} }
else else
{ {
fill_buffer_utf32(); // get the current character
} const int wc = static_cast<int>(str[current_wchar++]);
assert(utf8_bytes_filled > 0); // UTF-32 to UTF-8 encoding
assert(utf8_bytes_index == 0); if (wc < 0x80)
{
utf8_bytes[0] = wc;
utf8_bytes_filled = 1;
} }
else if (wc <= 0x7FF)
// use buffer {
assert(utf8_bytes_filled > 0); utf8_bytes[0] = 0xC0 | ((wc >> 6) & 0x1F);
assert(utf8_bytes_index < utf8_bytes_filled); utf8_bytes[1] = 0x80 | (wc & 0x3F);
return utf8_bytes[utf8_bytes_index++]; utf8_bytes_filled = 2;
} }
else if (wc <= 0xFFFF)
{
utf8_bytes[0] = 0xE0 | ((wc >> 12) & 0x0F);
utf8_bytes[1] = 0x80 | ((wc >> 6) & 0x3F);
utf8_bytes[2] = 0x80 | (wc & 0x3F);
utf8_bytes_filled = 3;
}
else if (wc <= 0x10FFFF)
{
utf8_bytes[0] = 0xF0 | ((wc >> 18) & 0x07);
utf8_bytes[1] = 0x80 | ((wc >> 12) & 0x3F);
utf8_bytes[2] = 0x80 | ((wc >> 6) & 0x3F);
utf8_bytes[3] = 0x80 | (wc & 0x3F);
utf8_bytes_filled = 4;
}
else
{
// unknown character
utf8_bytes[0] = wc;
utf8_bytes_filled = 1;
}
}
}
};
private: template<typename WideStringType>
void fill_buffer_utf16() struct wide_string_input_helper<WideStringType, 2>
{
// UTF-16
static void fill_buffer(const WideStringType& str, size_t& current_wchar, std::array<std::char_traits<char>::int_type, 4>& utf8_bytes, size_t& utf8_bytes_index, size_t& utf8_bytes_filled)
{ {
utf8_bytes_index = 0; utf8_bytes_index = 0;
@ -2079,58 +2107,38 @@ class wide_string_input_adapter : public input_adapter_protocol
} }
} }
} }
};
void fill_buffer_utf32() template<typename WideStringType>
{ class wide_string_input_adapter : public input_adapter_protocol
utf8_bytes_index = 0; {
public:
explicit wide_string_input_adapter(const WideStringType& w) : str(w) {}
if (current_wchar == str.size()) std::char_traits<char>::int_type get_character() noexcept override
{ {
utf8_bytes[0] = std::char_traits<char>::eof(); // check if buffer needs to be filled
utf8_bytes_filled = 1; if (utf8_bytes_index == utf8_bytes_filled)
}
else
{ {
// get the current character fill_buffer<sizeof(typename WideStringType::value_type)>();
const int wc = static_cast<int>(str[current_wchar++]);
// UTF-32 to UTF-8 encoding assert(utf8_bytes_filled > 0);
if (wc < 0x80) assert(utf8_bytes_index == 0);
{
utf8_bytes[0] = wc;
utf8_bytes_filled = 1;
}
else if (wc <= 0x7FF)
{
utf8_bytes[0] = 0xC0 | ((wc >> 6) & 0x1F);
utf8_bytes[1] = 0x80 | (wc & 0x3F);
utf8_bytes_filled = 2;
}
else if (wc <= 0xFFFF)
{
utf8_bytes[0] = 0xE0 | ((wc >> 12) & 0x0F);
utf8_bytes[1] = 0x80 | ((wc >> 6) & 0x3F);
utf8_bytes[2] = 0x80 | (wc & 0x3F);
utf8_bytes_filled = 3;
}
else if (wc <= 0x10FFFF)
{
utf8_bytes[0] = 0xF0 | ((wc >> 18 ) & 0x07);
utf8_bytes[1] = 0x80 | ((wc >> 12) & 0x3F);
utf8_bytes[2] = 0x80 | ((wc >> 6) & 0x3F);
utf8_bytes[3] = 0x80 | (wc & 0x3F);
utf8_bytes_filled = 4;
}
else
{
// unknown character
utf8_bytes[0] = wc;
utf8_bytes_filled = 1;
}
} }
// use buffer
assert(utf8_bytes_filled > 0);
assert(utf8_bytes_index < utf8_bytes_filled);
return utf8_bytes[utf8_bytes_index++];
} }
private: private:
template<size_t T>
void fill_buffer()
{
wide_string_input_helper<WideStringType, T>::fill_buffer(str, current_wchar, utf8_bytes, utf8_bytes_index, utf8_bytes_filled);
}
/// the wstring to process /// the wstring to process
const WideStringType& str; const WideStringType& str;
@ -2146,6 +2154,8 @@ class wide_string_input_adapter : public input_adapter_protocol
std::size_t utf8_bytes_filled = 0; std::size_t utf8_bytes_filled = 0;
}; };
class input_adapter class input_adapter
{ {
public: public: