circuitpython/py/parsenum.c
Damien George 04b9147e15 Add license header to (almost) all files.
Blanket wide to all .c and .h files.  Some files originating from ST are
difficult to deal with (license wise) so it was left out of those.

Also merged modpyb.h, modos.h, modstm.h and modtime.h in stmhal/.
2014-05-03 23:27:38 +01:00

253 lines
7.4 KiB
C

/*
* This file is part of the Micro Python project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2013, 2014 Damien P. George
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include <stdbool.h>
#include <stdlib.h>
#include "misc.h"
#include "mpconfig.h"
#include "qstr.h"
#include "nlr.h"
#include "obj.h"
#include "parsenumbase.h"
#include "parsenum.h"
#if MICROPY_ENABLE_FLOAT
#include <math.h>
#endif
mp_obj_t mp_parse_num_integer(const char *restrict str, uint len, int base) {
const char *restrict top = str + len;
bool neg = false;
// check radix base
if ((base != 0 && base < 2) || base > 36) {
nlr_raise(mp_obj_new_exception_msg(&mp_type_ValueError, "int() arg 2 must be >= 2 and <= 36"));
}
// skip leading space
for (; str < top && unichar_isspace(*str); str++) {
}
// parse optional sign
if (str < top) {
if (*str == '+') {
str++;
} else if (*str == '-') {
str++;
neg = true;
}
}
// parse optional base prefix
str += mp_parse_num_base(str, top - str, &base);
// string should be an integer number
machine_int_t int_val = 0;
const char *restrict str_val_start = str;
for (; str < top; str++) {
machine_int_t old_val = int_val;
int dig = *str;
if (unichar_isdigit(dig) && dig - '0' < base) {
// 0-9 digit
int_val = base * int_val + dig - '0';
} else if (base == 16) {
dig |= 0x20;
if ('a' <= dig && dig <= 'f') {
// a-f hex digit
int_val = base * int_val + dig - 'a' + 10;
} else {
// unknown character
break;
}
} else {
// unknown character
break;
}
if (int_val < old_val) {
// If new value became less than previous, it's overflow
goto overflow;
} else if ((old_val ^ int_val) & WORD_MSBIT_HIGH) {
// If signed number changed sign - it's overflow
goto overflow;
}
}
// check we parsed something
if (str == str_val_start) {
goto value_error;
}
// negate value if needed
if (neg) {
int_val = -int_val;
}
// skip trailing space
for (; str < top && unichar_isspace(*str); str++) {
}
// check we reached the end of the string
if (str != top) {
goto value_error;
}
// return the object
return MP_OBJ_NEW_SMALL_INT(int_val);
value_error:
nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError, "invalid literal for int() with base %d: '%s'", base, str));
overflow:
// TODO reparse using bignum
nlr_raise(mp_obj_new_exception_msg(&mp_type_ValueError, "overflow parsing integer"));
}
#define PARSE_DEC_IN_INTG (1)
#define PARSE_DEC_IN_FRAC (2)
#define PARSE_DEC_IN_EXP (3)
mp_obj_t mp_parse_num_decimal(const char *str, uint len, bool allow_imag, bool force_complex) {
#if MICROPY_ENABLE_FLOAT
const char *top = str + len;
mp_float_t dec_val = 0;
bool dec_neg = false;
bool imag = false;
// skip leading space
for (; str < top && unichar_isspace(*str); str++) {
}
// parse optional sign
if (str < top) {
if (*str == '+') {
str++;
} else if (*str == '-') {
str++;
dec_neg = true;
}
}
// determine what the string is
if (str < top && (str[0] | 0x20) == 'i') {
// string starts with 'i', should be 'inf' or 'infinity' (case insensitive)
if (str + 2 < top && (str[1] | 0x20) == 'n' && (str[2] | 0x20) == 'f') {
// inf
str += 3;
dec_val = INFINITY;
if (str + 4 < top && (str[0] | 0x20) == 'i' && (str[1] | 0x20) == 'n' && (str[2] | 0x20) == 'i' && (str[3] | 0x20) == 't' && (str[4] | 0x20) == 'y') {
// infinity
str += 5;
}
}
} else if (str < top && (str[0] | 0x20) == 'n') {
// string starts with 'n', should be 'nan' (case insensitive)
if (str + 2 < top && (str[1] | 0x20) == 'a' && (str[2] | 0x20) == 'n') {
// NaN
str += 3;
dec_val = MICROPY_FLOAT_C_FUN(nan)("");
}
} else {
// string should be a decimal number
int in = PARSE_DEC_IN_INTG;
bool exp_neg = false;
int exp_val = 0;
int exp_extra = 0;
for (; str < top; str++) {
int dig = *str;
if ('0' <= dig && dig <= '9') {
dig -= '0';
if (in == PARSE_DEC_IN_EXP) {
exp_val = 10 * exp_val + dig;
} else {
dec_val = 10 * dec_val + dig;
if (in == PARSE_DEC_IN_FRAC) {
exp_extra -= 1;
}
}
} else if (in == PARSE_DEC_IN_INTG && dig == '.') {
in = PARSE_DEC_IN_FRAC;
} else if (in != PARSE_DEC_IN_EXP && ((dig | 0x20) == 'e')) {
in = PARSE_DEC_IN_EXP;
if (str[1] == '+') {
str++;
} else if (str[1] == '-') {
str++;
exp_neg = true;
}
} else if (allow_imag && (dig | 0x20) == 'j') {
str++;
imag = true;
break;
} else {
// unknown character
break;
}
}
// work out the exponent
if (exp_neg) {
exp_val = -exp_val;
}
exp_val += exp_extra;
// apply the exponent
for (; exp_val > 0; exp_val--) {
dec_val *= 10;
}
for (; exp_val < 0; exp_val++) {
dec_val *= 0.1;
}
}
// negate value if needed
if (dec_neg) {
dec_val = -dec_val;
}
// skip trailing space
for (; str < top && unichar_isspace(*str); str++) {
}
// check we reached the end of the string
if (str != top) {
nlr_raise(mp_obj_new_exception_msg(&mp_type_SyntaxError, "invalid syntax for number"));
}
// return the object
if (imag) {
return mp_obj_new_complex(0, dec_val);
} else if (force_complex) {
return mp_obj_new_complex(dec_val, 0);
} else {
return mp_obj_new_float(dec_val);
}
#else
nlr_raise(mp_obj_new_exception_msg(&mp_type_SyntaxError, "decimal numbers not supported"));
#endif
}