diff --git a/src/json.hpp b/src/json.hpp index c77945a87..25723b4a2 100644 --- a/src/json.hpp +++ b/src/json.hpp @@ -10838,59 +10838,202 @@ basic_json_parser_66: return result; } - /*! - @brief parse floating point number - - This function (and its overloads) serves to select the most approprate - standard floating point number parsing function based on the type - supplied via the first parameter. Set this to @a - static_cast(nullptr). - - @param[in,out] endptr recieves a pointer to the first character after - the number - - @return the floating point number - */ - long double str_to_float_t(long double* /* type */, char** endptr) const - { - return std::strtold(reinterpret_cast(m_start), endptr); - } /*! - @brief parse floating point number + @brief parse string into a built-in arithmetic type as if + the current locale is POSIX. - This function (and its overloads) serves to select the most approprate - standard floating point number parsing function based on the type - supplied via the first parameter. Set this to @a - static_cast(nullptr). + note: in floating-point case strtod may parse + past the token's end - this is not an error. - @param[in,out] endptr recieves a pointer to the first character after - the number - - @return the floating point number + any leading blanks are not handled. */ - double str_to_float_t(double* /* type */, char** endptr) const + struct strtonum { - return std::strtod(reinterpret_cast(m_start), endptr); - } + public: + strtonum(const char* start, const char* end) + : m_start(start), m_end(end) + {} - /*! - @brief parse floating point number + /// return true iff parsed successfully as + /// number of type T. + /// + /// @val shall contain parsed value, or + /// undefined value if could not parse. + template::value>::type > + bool to(T& val) const + { + return parse(val, std::is_integral()); + } - This function (and its overloads) serves to select the most approprate - standard floating point number parsing function based on the type - supplied via the first parameter. Set this to @a - static_cast(nullptr). + /// return true iff token matches ^[+-]\d+$ + /// + /// this is a helper to determine whether to + /// parse the token into floating-point or + /// integral type. We wouldn't need it if + /// we had separate token types for integral + /// and floating-point cases. + bool is_integral() const + { + const char* p = m_start; - @param[in,out] endptr recieves a pointer to the first character after - the number + if (!p) + { + return false; // LCOV_EXCL_LINE + } - @return the floating point number - */ - float str_to_float_t(float* /* type */, char** endptr) const - { - return std::strtof(reinterpret_cast(m_start), endptr); - } + if (*p == '-' or * p == '+') + { + ++p; + } + + if (p == m_end) + { + return false; // LCOV_EXCL_LINE + } + + while (p < m_end and* p >= '0' + and * p <= '9') + { + ++p; + } + + return p == m_end; + } + + private: + const char* const m_start = nullptr; + const char* const m_end = nullptr; + + // overloaded wrappers for strtod/strtof/strtold + // that will be called from parse + + static void strtof(float& f, + const char* str, + char** endptr) + { + f = std::strtof(str, endptr); + } + + static void strtof(double& f, + const char* str, + char** endptr) + { + f = std::strtod(str, endptr); + } + + static void strtof(long double& f, + const char* str, + char** endptr) + { + f = std::strtold(str, endptr); + } + + template + bool parse(T& value, /*is_integral=*/std::false_type) const + { + // replace decimal separator with locale-specific + // version, when necessary; data will point to + // either the original string, or buf, or tempstr + // containing the fixed string. + std::string tempstr; + std::array buf; + const size_t len = static_cast(m_end - m_start); + + // Since dealing with strtod family of functions, + // we're getting the decimal point char from the + // C locale facilities instead of C++'s numpunct + // facet of the current std::locale; + const auto loc = localeconv(); + assert(loc != nullptr); + const char decimal_point_char = !loc->decimal_point ? '.' + : loc->decimal_point[0]; + + const char* data = m_start; + + if (decimal_point_char != '.') + { + const size_t ds_pos = static_cast( + std::find(m_start, m_end, '.') - m_start ); + + if (ds_pos != len) + { + // copy the data into the local buffer or + // tempstr, if buffer is too small; + // replace decimal separator, and update + // data to point to the modified bytes + if (len + 1 < buf.size()) + { + std::copy(m_start, m_end, buf.data()); + buf[len] = 0; + buf[ds_pos] = decimal_point_char; + data = buf.data(); + } + else + { + tempstr.assign(m_start, m_end); + tempstr[ds_pos] = decimal_point_char; + data = tempstr.c_str(); + } + } + } + + char* endptr = nullptr; + value = 0; + // this calls appropriate overload depending on T + strtof(value, data, &endptr); + + // note that reading past the end is OK, the data may be, + // for example, "123.", where the parsed token only + // contains "123", but strtod will read the dot as well. + const bool ok = endptr >= data + len + and len > 0; + + if (ok and value == 0.0 and * data == '-') + { + // some implementations forget to negate the zero + value = -0.0; + } + + return ok; + } + + signed long long parse_integral( + char** endptr, + /*is_signed*/std::true_type) const + { + return std::strtoll(m_start, endptr, 10); + } + + unsigned long long parse_integral( + char** endptr, + /*is_signed*/std::false_type) const + { + return std::strtoull(m_start, endptr, 10); + } + + template + bool parse(T& value, /*is_integral=*/std::true_type) const + { + char* endptr = nullptr; + errno = 0; // these are thread-local + const auto x = parse_integral(&endptr, std::is_signed()); + + static_assert(std::is_signed() // called right overload? + == std::is_signed(), ""); + + value = static_cast(x); + + return x == static_cast(value) // x fits into destination T + and (x < 0) == (value < 0) // preserved sign + and (x != 0 or is_integral()) // strto[u]ll did nto fail + and errno == 0 // strto[u]ll did not overflow + and m_start < m_end // token was not empty + and endptr == m_end; // parsed entire token exactly + } + }; /*! @brief return number value for number tokens @@ -10899,125 +11042,69 @@ basic_json_parser_66: number type (either integer, unsigned integer or floating point), which is passed back to the caller via the result parameter. - This function parses the integer component up to the radix point or - exponent while collecting information about the 'floating point - representation', which it stores in the result parameter. If there is - no radix point or exponent, and the number can fit into a @ref - number_integer_t or @ref number_unsigned_t then it sets the result - parameter accordingly. + integral numbers that don't fit into the the range of the respective + type are parsed as number_float_t - If the number is a floating point number the number is then parsed - using @a std:strtod (or @a std:strtof or @a std::strtold). + floating-point values do not satisfy std::isfinite predicate + are converted to value_t::null - @param[out] result @ref basic_json object to receive the number, or - NAN if the conversion read past the current token. The latter case - needs to be treated by the caller function. + throws if the entire string [m_start .. m_cursor) cannot be + interpreted as a number + + @param[out] result @ref basic_json object to receive the number. */ void get_number(basic_json& result) const { assert(m_start != nullptr); + assert(m_start < m_cursor); - const lexer::lexer_char_t* curptr = m_start; + strtonum num(reinterpret_cast(m_start), + reinterpret_cast(m_cursor)); - // accumulate the integer conversion result (unsigned for now) - number_unsigned_t value = 0; + const bool is_negative = *m_start == '-'; - // maximum absolute value of the relevant integer type - number_unsigned_t max; + result.m_type = value_t::discarded; - // temporarily store the type to avoid unecessary bitfield access - value_t type; - - // look for sign - if (*curptr == '-') + if (not num.is_integral()) { - type = value_t::number_integer; - max = static_cast((std::numeric_limits::max)()) + 1; - curptr++; + ; // will parse as float below } - else + else if (is_negative) { - type = value_t::number_unsigned; - max = static_cast((std::numeric_limits::max)()); - } - - // count the significant figures - for (; curptr < m_cursor; curptr++) - { - // quickly skip tests if a digit - if (*curptr < '0' or* curptr > '9') + number_integer_t val{0}; + if (num.to(val)) { - if (*curptr == '.') - { - // don't count '.' but change to float - type = value_t::number_float; - continue; - } - // assume exponent (if not then will fail parse): change to - // float, stop counting and record exponent details - type = value_t::number_float; - break; - } - - // skip if definitely not an integer - if (type != value_t::number_float) - { - auto digit = static_cast(*curptr - '0'); - - // overflow if value * 10 + digit > max, move terms around - // to avoid overflow in intermediate values - if (value > (max - digit) / 10) - { - // overflow - type = value_t::number_float; - } - else - { - // no overflow - value = value * 10 + digit; - } - } - } - - // save the value (if not a float) - if (type == value_t::number_unsigned) - { - result.m_value.number_unsigned = value; - } - else if (type == value_t::number_integer) - { - // invariant: if we parsed a '-', the absolute value is between - // 0 (we allow -0) and max == -INT64_MIN - assert(value >= 0); - assert(value <= max); - - if (value == max) - { - // we cannot simply negate value (== max == -INT64_MIN), - // see https://github.com/nlohmann/json/issues/389 - result.m_value.number_integer = static_cast(INT64_MIN); - } - else - { - // all other values can be negated safely - result.m_value.number_integer = -static_cast(value); + result.m_type = value_t::number_integer; + result.m_value = val; } } else { - // parse with strtod - result.m_value.number_float = str_to_float_t(static_cast(nullptr), nullptr); - - // replace infinity and NAN by null - if (not std::isfinite(result.m_value.number_float)) + number_unsigned_t val{0}; + if (num.to(val)) { - type = value_t::null; - result.m_value = basic_json::json_value(); + result.m_type = value_t::number_unsigned; + result.m_value = val; } } - // save the type - result.m_type = type; + number_float_t val{0}; + if (result.m_type != value_t::discarded + or !num.to(val)) + { + return; // already have a value from above + // or couldn't parse as float_t + } + + result.m_type = value_t::number_float; + result.m_value = val; + + // replace infinity and NAN by null + if (not std::isfinite(result.m_value.number_float)) + { + result.m_type = value_t::null; + result.m_value = basic_json::json_value(); + } } private: diff --git a/src/json.hpp.re2c b/src/json.hpp.re2c index 109a4f262..cba233c9e 100644 --- a/src/json.hpp.re2c +++ b/src/json.hpp.re2c @@ -9988,59 +9988,202 @@ class basic_json return result; } - /*! - @brief parse floating point number - - This function (and its overloads) serves to select the most approprate - standard floating point number parsing function based on the type - supplied via the first parameter. Set this to @a - static_cast(nullptr). - - @param[in,out] endptr recieves a pointer to the first character after - the number - - @return the floating point number - */ - long double str_to_float_t(long double* /* type */, char** endptr) const - { - return std::strtold(reinterpret_cast(m_start), endptr); - } /*! - @brief parse floating point number + @brief parse string into a built-in arithmetic type as if + the current locale is POSIX. - This function (and its overloads) serves to select the most approprate - standard floating point number parsing function based on the type - supplied via the first parameter. Set this to @a - static_cast(nullptr). + note: in floating-point case strtod may parse + past the token's end - this is not an error. - @param[in,out] endptr recieves a pointer to the first character after - the number - - @return the floating point number + any leading blanks are not handled. */ - double str_to_float_t(double* /* type */, char** endptr) const + struct strtonum { - return std::strtod(reinterpret_cast(m_start), endptr); - } + public: + strtonum(const char* start, const char* end) + : m_start(start), m_end(end) + {} - /*! - @brief parse floating point number + /// return true iff parsed successfully as + /// number of type T. + /// + /// @val shall contain parsed value, or + /// undefined value if could not parse. + template::value>::type > + bool to(T& val) const + { + return parse(val, std::is_integral()); + } - This function (and its overloads) serves to select the most approprate - standard floating point number parsing function based on the type - supplied via the first parameter. Set this to @a - static_cast(nullptr). + /// return true iff token matches ^[+-]\d+$ + /// + /// this is a helper to determine whether to + /// parse the token into floating-point or + /// integral type. We wouldn't need it if + /// we had separate token types for integral + /// and floating-point cases. + bool is_integral() const + { + const char* p = m_start; - @param[in,out] endptr recieves a pointer to the first character after - the number + if (!p) + { + return false; // LCOV_EXCL_LINE + } - @return the floating point number - */ - float str_to_float_t(float* /* type */, char** endptr) const - { - return std::strtof(reinterpret_cast(m_start), endptr); - } + if (*p == '-' or * p == '+') + { + ++p; + } + + if (p == m_end) + { + return false; // LCOV_EXCL_LINE + } + + while (p < m_end and* p >= '0' + and * p <= '9') + { + ++p; + } + + return p == m_end; + } + + private: + const char* const m_start = nullptr; + const char* const m_end = nullptr; + + // overloaded wrappers for strtod/strtof/strtold + // that will be called from parse + + static void strtof(float& f, + const char* str, + char** endptr) + { + f = std::strtof(str, endptr); + } + + static void strtof(double& f, + const char* str, + char** endptr) + { + f = std::strtod(str, endptr); + } + + static void strtof(long double& f, + const char* str, + char** endptr) + { + f = std::strtold(str, endptr); + } + + template + bool parse(T& value, /*is_integral=*/std::false_type) const + { + // replace decimal separator with locale-specific + // version, when necessary; data will point to + // either the original string, or buf, or tempstr + // containing the fixed string. + std::string tempstr; + std::array buf; + const size_t len = static_cast(m_end - m_start); + + // Since dealing with strtod family of functions, + // we're getting the decimal point char from the + // C locale facilities instead of C++'s numpunct + // facet of the current std::locale; + const auto loc = localeconv(); + assert(loc != nullptr); + const char decimal_point_char = !loc->decimal_point ? '.' + : loc->decimal_point[0]; + + const char* data = m_start; + + if (decimal_point_char != '.') + { + const size_t ds_pos = static_cast( + std::find(m_start, m_end, '.') - m_start ); + + if (ds_pos != len) + { + // copy the data into the local buffer or + // tempstr, if buffer is too small; + // replace decimal separator, and update + // data to point to the modified bytes + if (len + 1 < buf.size()) + { + std::copy(m_start, m_end, buf.data()); + buf[len] = 0; + buf[ds_pos] = decimal_point_char; + data = buf.data(); + } + else + { + tempstr.assign(m_start, m_end); + tempstr[ds_pos] = decimal_point_char; + data = tempstr.c_str(); + } + } + } + + char* endptr = nullptr; + value = 0; + // this calls appropriate overload depending on T + strtof(value, data, &endptr); + + // note that reading past the end is OK, the data may be, + // for example, "123.", where the parsed token only + // contains "123", but strtod will read the dot as well. + const bool ok = endptr >= data + len + and len > 0; + + if (ok and value == 0.0 and * data == '-') + { + // some implementations forget to negate the zero + value = -0.0; + } + + return ok; + } + + signed long long parse_integral( + char** endptr, + /*is_signed*/std::true_type) const + { + return std::strtoll(m_start, endptr, 10); + } + + unsigned long long parse_integral( + char** endptr, + /*is_signed*/std::false_type) const + { + return std::strtoull(m_start, endptr, 10); + } + + template + bool parse(T& value, /*is_integral=*/std::true_type) const + { + char* endptr = nullptr; + errno = 0; // these are thread-local + const auto x = parse_integral(&endptr, std::is_signed()); + + static_assert(std::is_signed() // called right overload? + == std::is_signed(), ""); + + value = static_cast(x); + + return x == static_cast(value) // x fits into destination T + and (x < 0) == (value < 0) // preserved sign + and (x != 0 or is_integral()) // strto[u]ll did nto fail + and errno == 0 // strto[u]ll did not overflow + and m_start < m_end // token was not empty + and endptr == m_end; // parsed entire token exactly + } + }; /*! @brief return number value for number tokens @@ -10049,125 +10192,69 @@ class basic_json number type (either integer, unsigned integer or floating point), which is passed back to the caller via the result parameter. - This function parses the integer component up to the radix point or - exponent while collecting information about the 'floating point - representation', which it stores in the result parameter. If there is - no radix point or exponent, and the number can fit into a @ref - number_integer_t or @ref number_unsigned_t then it sets the result - parameter accordingly. + integral numbers that don't fit into the the range of the respective + type are parsed as number_float_t - If the number is a floating point number the number is then parsed - using @a std:strtod (or @a std:strtof or @a std::strtold). + floating-point values do not satisfy std::isfinite predicate + are converted to value_t::null - @param[out] result @ref basic_json object to receive the number, or - NAN if the conversion read past the current token. The latter case - needs to be treated by the caller function. + throws if the entire string [m_start .. m_cursor) cannot be + interpreted as a number + + @param[out] result @ref basic_json object to receive the number. */ void get_number(basic_json& result) const { assert(m_start != nullptr); + assert(m_start < m_cursor); - const lexer::lexer_char_t* curptr = m_start; + strtonum num(reinterpret_cast(m_start), + reinterpret_cast(m_cursor)); - // accumulate the integer conversion result (unsigned for now) - number_unsigned_t value = 0; + const bool is_negative = *m_start == '-'; - // maximum absolute value of the relevant integer type - number_unsigned_t max; + result.m_type = value_t::discarded; - // temporarily store the type to avoid unecessary bitfield access - value_t type; - - // look for sign - if (*curptr == '-') + if (not num.is_integral()) { - type = value_t::number_integer; - max = static_cast((std::numeric_limits::max)()) + 1; - curptr++; + ; // will parse as float below } - else + else if (is_negative) { - type = value_t::number_unsigned; - max = static_cast((std::numeric_limits::max)()); - } - - // count the significant figures - for (; curptr < m_cursor; curptr++) - { - // quickly skip tests if a digit - if (*curptr < '0' or* curptr > '9') + number_integer_t val{0}; + if (num.to(val)) { - if (*curptr == '.') - { - // don't count '.' but change to float - type = value_t::number_float; - continue; - } - // assume exponent (if not then will fail parse): change to - // float, stop counting and record exponent details - type = value_t::number_float; - break; - } - - // skip if definitely not an integer - if (type != value_t::number_float) - { - auto digit = static_cast(*curptr - '0'); - - // overflow if value * 10 + digit > max, move terms around - // to avoid overflow in intermediate values - if (value > (max - digit) / 10) - { - // overflow - type = value_t::number_float; - } - else - { - // no overflow - value = value * 10 + digit; - } - } - } - - // save the value (if not a float) - if (type == value_t::number_unsigned) - { - result.m_value.number_unsigned = value; - } - else if (type == value_t::number_integer) - { - // invariant: if we parsed a '-', the absolute value is between - // 0 (we allow -0) and max == -INT64_MIN - assert(value >= 0); - assert(value <= max); - - if (value == max) - { - // we cannot simply negate value (== max == -INT64_MIN), - // see https://github.com/nlohmann/json/issues/389 - result.m_value.number_integer = static_cast(INT64_MIN); - } - else - { - // all other values can be negated safely - result.m_value.number_integer = -static_cast(value); + result.m_type = value_t::number_integer; + result.m_value = val; } } else { - // parse with strtod - result.m_value.number_float = str_to_float_t(static_cast(nullptr), nullptr); - - // replace infinity and NAN by null - if (not std::isfinite(result.m_value.number_float)) + number_unsigned_t val{0}; + if (num.to(val)) { - type = value_t::null; - result.m_value = basic_json::json_value(); + result.m_type = value_t::number_unsigned; + result.m_value = val; } } - // save the type - result.m_type = type; + number_float_t val{0}; + if (result.m_type != value_t::discarded + or !num.to(val)) + { + return; // already have a value from above + // or couldn't parse as float_t + } + + result.m_type = value_t::number_float; + result.m_value = val; + + // replace infinity and NAN by null + if (not std::isfinite(result.m_value.number_float)) + { + result.m_type = value_t::null; + result.m_value = basic_json::json_value(); + } } private: diff --git a/test/src/unit-regression.cpp b/test/src/unit-regression.cpp index 17edbd5ea..251c4cb82 100644 --- a/test/src/unit-regression.cpp +++ b/test/src/unit-regression.cpp @@ -383,7 +383,7 @@ TEST_CASE("regression tests") }; // change locale to mess with decimal points - std::locale::global(std::locale(std::locale(), new CommaDecimalSeparator)); + auto orig_locale = std::locale::global(std::locale(std::locale(), new CommaDecimalSeparator)); CHECK(j1a.dump() == "23.42"); CHECK(j1b.dump() == "23.42"); @@ -407,8 +407,34 @@ TEST_CASE("regression tests") CHECK(j3c.dump() == "10000"); //CHECK(j3b.dump() == "1E04"); // roundtrip error //CHECK(j3c.dump() == "1e04"); // roundtrip error + + std::locale::global(orig_locale); } + SECTION("issue #379 - locale-independent str-to-num") + { + setlocale(LC_NUMERIC, "de_DE.UTF-8"); + + // disabled, because locale-specific beharivor is not + // triggered in AppVeyor for some reason +#if 0 + { + // verify that strtod now uses commas as decimal-separator + CHECK(std::strtod("3,14", nullptr) == 3.14); + + // verify that strtod does not understand dots as decimal separator + CHECK(std::strtod("3.14", nullptr) == 3); + } +#endif + + // verify that parsed correctly despite using strtod internally + CHECK(json::parse("3.14").get() == 3.14); + + // check a different code path + CHECK(json::parse("1.000000000000000000000000000000000000000000000000000000000000000000000000").get() == 1.0); + } + + SECTION("issue #233 - Can't use basic_json::iterator as a base iterator for std::move_iterator") { json source = {"a", "b", "c"};