diff --git a/float_parser_tests.cc b/float_parser_tests.cc deleted file mode 100644 index 420adea..0000000 --- a/float_parser_tests.cc +++ /dev/null @@ -1,231 +0,0 @@ -#include -#include -#include -#include -#include - -// Tries to parse a floating point number located at s. -// -// s_end should be a location in the string where reading should absolutely -// stop. For example at the end of the string, to prevent buffer overflows. -// -// Parses the following EBNF grammar: -// sign = "+" | "-" ; -// END = ? anything not in digit ? -// digit = "0" | "1" | "2" | "3" | "4" | "5" | "6" | "7" | "8" | "9" ; -// integer = [sign] , digit , {digit} ; -// decimal = integer , ["." , integer] ; -// float = ( decimal , END ) | ( decimal , ("E" | "e") , integer , END ) ; -// -// Valid strings are for example: -// -0 +3.1417e+2 -0.0E-3 1.0324 -1.41 11e2 -// -// If the parsing is a success, result is set to the parsed value and true -// is returned. -// -// The function is greedy and will parse until any of the following happens: -// - a non-conforming character is encountered. -// - s_end is reached. -// -// The following situations triggers a failure: -// - s >= s_end. -// - parse failure. -// -bool tryParseDouble(const char *s, const char *s_end, double *result) -{ - if (s >= s_end) - { - return false; - } - - double mantissa = 0.0; - // This exponent is base 2 rather than 10. - // However the exponent we parse is supposed to be one of ten, - // thus we must take care to convert the exponent/and or the - // mantissa to a * 2^E, where a is the mantissa and E is the - // exponent. - // To get the final double we will use ldexp, it requires the - // exponent to be in base 2. - int exponent = 0; - - // NOTE: THESE MUST BE DECLARED HERE SINCE WE ARE NOT ALLOWED - // TO JUMP OVER DEFINITIONS. - char sign = '+'; - char exp_sign = '+'; - char const *curr = s; - - // How many characters were read in a loop. - int read = 0; - // Tells whether a loop terminated due to reaching s_end. - bool end_not_reached = false; - - /* - BEGIN PARSING. - */ - - // Find out what sign we've got. - if (*curr == '+' || *curr == '-') - { - sign = *curr; - curr++; - } - else if (isdigit(*curr)) { /* Pass through. */ } - else - { - goto fail; - } - - // Read the integer part. - while ((end_not_reached = (curr != s_end)) && isdigit(*curr)) - { - mantissa *= 10; - mantissa += static_cast(*curr - 0x30); - curr++; read++; - } - - // We must make sure we actually got something. - if (read == 0) - goto fail; - // We allow numbers of form "#", "###" etc. - if (!end_not_reached) - goto assemble; - - // Read the decimal part. - if (*curr == '.') - { - curr++; - read = 1; - while ((end_not_reached = (curr != s_end)) && isdigit(*curr)) - { - // NOTE: Don't use powf here, it will absolutely murder precision. - mantissa += static_cast(*curr - 0x30) * pow(10, -read); - read++; curr++; - } - } - else if (*curr == 'e' || *curr == 'E') {} - else - { - goto assemble; - } - - if (!end_not_reached) - goto assemble; - - // Read the exponent part. - if (*curr == 'e' || *curr == 'E') - { - curr++; - // Figure out if a sign is present and if it is. - if ((end_not_reached = (curr != s_end)) && (*curr == '+' || *curr == '-')) - { - exp_sign = *curr; - curr++; - } - else if (isdigit(*curr)) { /* Pass through. */ } - else - { - // Empty E is not allowed. - goto fail; - } - - read = 0; - while ((end_not_reached = (curr != s_end)) && isdigit(*curr)) - { - exponent *= 10; - exponent += static_cast(*curr - 0x30); - curr++; read++; - } - exponent *= (exp_sign == '+'? 1 : -1); - if (read == 0) - goto fail; - } - -assemble: - *result = (sign == '+'? 1 : -1) * ldexp(mantissa * pow(5, exponent), exponent); - return true; -fail: - return false; -} - -void testParsing(const char *input, bool expectedRes, double expectedValue) -{ - double val = 0.0; - bool res = tryParseDouble(input, input + strlen(input), &val); - if (res != expectedRes || fabs(val - expectedValue) > 0.000001) - { - printf("% 20s failed, returned %d and value % 10.5f.\n\t\tExpected value was % 10.5f\n------\n", input, res, val, expectedValue); - } -} - -int main(int argc, char const *argv[]) -{ - testParsing("0", true, 0.0); - testParsing("-0", true, 0.0); - testParsing("+0", true, 0.0); - testParsing("1", true, 1.0); - testParsing("+1", true, 1.0); - testParsing("-1", true, -1.0); - testParsing("-1.08", true, -1.08); - testParsing("100.0823blabla", true, 100.0823); - testParsing("34.0E-2\04", true, 34.0e-2); - testParsing("+34.23E2\032", true, 34.23E2); - testParsing("10.023", true, 10.023); - testParsing("1.0e+23", true, 1.e+23); - testParsing("10e+23", true, 10e+23); - testParsing("20301.000", true, 20301.000); - testParsing("-41044.000", true, -41044.000); - testParsing("-93558.000", true, -93558.000); - testParsing("-79620.000", true, -79620.000); - testParsing("5257.000", true, 5257.000); - testParsing("-7145.000", true, -7145.000); - testParsing("-77314.000", true, -77314.000); - testParsing("-27131.000", true, -27131.000); - testParsing("52744.000", true, 52744.000); - testParsing("48106.000", true, 48106.000); - testParsing("42939.000", true, 42939.000); - testParsing("41187.000", true, 41187.000); - testParsing("70851.000", true, 70851.000); - testParsing("-90431.000", true, -90431.000); - testParsing("-13564.000", true, -13564.000); - testParsing("27150.000", true, 27150.000); - testParsing("71992.000", true, 71992.000); - testParsing("-42845.000", true, -42845.000); - testParsing("24806.000", true, 24806.000); - testParsing("30753.000", true, 30753.000); - testParsing("1.658500e+04", true, 1.658500e+04); - testParsing("9.572500e+04", true, 9.572500e+04); - testParsing("-5.888600e+04", true, -5.888600e+04); - testParsing("-2.998000e+04", true, -2.998000e+04); - testParsing("-4.842700e+04", true, -4.842700e+04); - testParsing("9.575400e+04", true, 9.575400e+04); - testParsing("-8.311500e+04", true, -8.311500e+04); - testParsing("-3.770800e+04", true, -3.770800e+04); - testParsing("-3.141600e+04", true, -3.141600e+04); - testParsing("-4.673700e+04", true, -4.673700e+04); - testParsing("-5.112400e+04", true, -5.112400e+04); - testParsing("7.111000e+03", true, 7.111000e+03); - testParsing("-3.727000e+03", true, -3.727000e+03); - testParsing("6.940700e+04", true, 6.940700e+04); - testParsing("-3.635100e+04", true, -3.635100e+04); - testParsing("2.762100e+04", true, 2.762100e+04); - testParsing("-1.512600e+04", true, -1.512600e+04); - testParsing("3.338000e+03", true, 3.338000e+03); - testParsing("7.598100e+04", true, 7.598100e+04); - testParsing("-8.198400e+04", true, -8.198400e+04); - testParsing("-", false, 0.0); - testParsing(" +", false, 0.0); - testParsing("", false, 0.0); - testParsing(".232", false, 0.0); - testParsing(".232E2", false, 0.0); - testParsing(".232", false, 0.0); - testParsing(".", false, 0.0); - testParsing(".E", false, 0.0); - testParsing("233.E", false, 0.0); - testParsing("233.323E-", false, 0.0); - testParsing("233.323E+", false, 0.0); - - - - - return 0; -} \ No newline at end of file