mirror of
https://github.com/jart/cosmopolitan.git
synced 2025-01-31 19:43:32 +00:00
9b29358511
Status lines for Emacs and Vim have been added to Python sources so they'll be easier to edit using Python's preferred coding style. Some DNS helper functions have been broken up into multiple files. It's nice to have one function per file whenever possible, since that way we don't need -ffunction-sections. Another reason it's good to have small source files, is because the build will be enforcing resource limits on compilation and testing soon.
290 lines
9 KiB
C
290 lines
9 KiB
C
/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:4;tab-width:8;coding:utf-8 -*-│
|
|
│vi: set net ft=c ts=4 sts=4 sw=4 fenc=utf-8 :vi│
|
|
╞══════════════════════════════════════════════════════════════════════════════╡
|
|
│ Python 3 │
|
|
│ https://docs.python.org/3/license.html │
|
|
╚─────────────────────────────────────────────────────────────────────────────*/
|
|
#include "libc/errno.h"
|
|
#include "libc/limits.h"
|
|
#include "third_party/python/Include/longobject.h"
|
|
#include "third_party/python/Include/pyctype.h"
|
|
#include "third_party/python/Include/pymacro.h"
|
|
#include "third_party/python/pyconfig.h"
|
|
/* clang-format off */
|
|
|
|
/* Static overflow check values for bases 2 through 36.
|
|
* smallmax[base] is the largest unsigned long i such that
|
|
* i * base doesn't overflow unsigned long.
|
|
*/
|
|
static const unsigned long smallmax[] = {
|
|
0, /* bases 0 and 1 are invalid */
|
|
0,
|
|
ULONG_MAX / 2,
|
|
ULONG_MAX / 3,
|
|
ULONG_MAX / 4,
|
|
ULONG_MAX / 5,
|
|
ULONG_MAX / 6,
|
|
ULONG_MAX / 7,
|
|
ULONG_MAX / 8,
|
|
ULONG_MAX / 9,
|
|
ULONG_MAX / 10,
|
|
ULONG_MAX / 11,
|
|
ULONG_MAX / 12,
|
|
ULONG_MAX / 13,
|
|
ULONG_MAX / 14,
|
|
ULONG_MAX / 15,
|
|
ULONG_MAX / 16,
|
|
ULONG_MAX / 17,
|
|
ULONG_MAX / 18,
|
|
ULONG_MAX / 19,
|
|
ULONG_MAX / 20,
|
|
ULONG_MAX / 21,
|
|
ULONG_MAX / 22,
|
|
ULONG_MAX / 23,
|
|
ULONG_MAX / 24,
|
|
ULONG_MAX / 25,
|
|
ULONG_MAX / 26,
|
|
ULONG_MAX / 27,
|
|
ULONG_MAX / 28,
|
|
ULONG_MAX / 29,
|
|
ULONG_MAX / 30,
|
|
ULONG_MAX / 31,
|
|
ULONG_MAX / 32,
|
|
ULONG_MAX / 33,
|
|
ULONG_MAX / 34,
|
|
ULONG_MAX / 35,
|
|
ULONG_MAX / 36,
|
|
};
|
|
|
|
/* maximum digits that can't ever overflow for bases 2 through 36,
|
|
* calculated by [int(math.floor(math.log(2**32, i))) for i in range(2, 37)].
|
|
* Note that this is pessimistic if sizeof(long) > 4.
|
|
*/
|
|
#if SIZEOF_LONG == 4
|
|
static const int digitlimit[] = {
|
|
0, 0, 32, 20, 16, 13, 12, 11, 10, 10, /* 0 - 9 */
|
|
9, 9, 8, 8, 8, 8, 8, 7, 7, 7, /* 10 - 19 */
|
|
7, 7, 7, 7, 6, 6, 6, 6, 6, 6, /* 20 - 29 */
|
|
6, 6, 6, 6, 6, 6, 6}; /* 30 - 36 */
|
|
#elif SIZEOF_LONG == 8
|
|
/* [int(math.floor(math.log(2**64, i))) for i in range(2, 37)] */
|
|
static const int digitlimit[] = {
|
|
0, 0, 64, 40, 32, 27, 24, 22, 21, 20, /* 0 - 9 */
|
|
19, 18, 17, 17, 16, 16, 16, 15, 15, 15, /* 10 - 19 */
|
|
14, 14, 14, 14, 13, 13, 13, 13, 13, 13, /* 20 - 29 */
|
|
13, 12, 12, 12, 12, 12, 12}; /* 30 - 36 */
|
|
#else
|
|
#error "Need table for SIZEOF_LONG"
|
|
#endif
|
|
|
|
/*
|
|
** strtoul
|
|
** This is a general purpose routine for converting
|
|
** an ascii string to an integer in an arbitrary base.
|
|
** Leading white space is ignored. If 'base' is zero
|
|
** it looks for a leading 0b, 0o or 0x to tell which
|
|
** base. If these are absent it defaults to 10.
|
|
** Base must be 0 or between 2 and 36 (inclusive).
|
|
** If 'ptr' is non-NULL it will contain a pointer to
|
|
** the end of the scan.
|
|
** Errors due to bad pointers will probably result in
|
|
** exceptions - we don't check for them.
|
|
*/
|
|
unsigned long
|
|
PyOS_strtoul(const char *str, char **ptr, int base)
|
|
{
|
|
unsigned long result = 0; /* return value of the function */
|
|
int c; /* current input character */
|
|
int ovlimit; /* required digits to overflow */
|
|
|
|
/* skip leading white space */
|
|
while (*str && Py_ISSPACE(Py_CHARMASK(*str)))
|
|
++str;
|
|
|
|
/* check for leading 0b, 0o or 0x for auto-base or base 16 */
|
|
switch (base) {
|
|
case 0: /* look for leading 0b, 0o or 0x */
|
|
if (*str == '0') {
|
|
++str;
|
|
if (*str == 'x' || *str == 'X') {
|
|
/* there must be at least one digit after 0x */
|
|
if (_PyLong_DigitValue[Py_CHARMASK(str[1])] >= 16) {
|
|
if (ptr)
|
|
*ptr = (char *)str;
|
|
return 0;
|
|
}
|
|
++str;
|
|
base = 16;
|
|
} else if (*str == 'o' || *str == 'O') {
|
|
/* there must be at least one digit after 0o */
|
|
if (_PyLong_DigitValue[Py_CHARMASK(str[1])] >= 8) {
|
|
if (ptr)
|
|
*ptr = (char *)str;
|
|
return 0;
|
|
}
|
|
++str;
|
|
base = 8;
|
|
} else if (*str == 'b' || *str == 'B') {
|
|
/* there must be at least one digit after 0b */
|
|
if (_PyLong_DigitValue[Py_CHARMASK(str[1])] >= 2) {
|
|
if (ptr)
|
|
*ptr = (char *)str;
|
|
return 0;
|
|
}
|
|
++str;
|
|
base = 2;
|
|
} else {
|
|
/* skip all zeroes... */
|
|
while (*str == '0')
|
|
++str;
|
|
while (Py_ISSPACE(Py_CHARMASK(*str)))
|
|
++str;
|
|
if (ptr)
|
|
*ptr = (char *)str;
|
|
return 0;
|
|
}
|
|
}
|
|
else
|
|
base = 10;
|
|
break;
|
|
|
|
/* even with explicit base, skip leading 0? prefix */
|
|
case 16:
|
|
if (*str == '0') {
|
|
++str;
|
|
if (*str == 'x' || *str == 'X') {
|
|
/* there must be at least one digit after 0x */
|
|
if (_PyLong_DigitValue[Py_CHARMASK(str[1])] >= 16) {
|
|
if (ptr)
|
|
*ptr = (char *)str;
|
|
return 0;
|
|
}
|
|
++str;
|
|
}
|
|
}
|
|
break;
|
|
case 8:
|
|
if (*str == '0') {
|
|
++str;
|
|
if (*str == 'o' || *str == 'O') {
|
|
/* there must be at least one digit after 0o */
|
|
if (_PyLong_DigitValue[Py_CHARMASK(str[1])] >= 8) {
|
|
if (ptr)
|
|
*ptr = (char *)str;
|
|
return 0;
|
|
}
|
|
++str;
|
|
}
|
|
}
|
|
break;
|
|
case 2:
|
|
if(*str == '0') {
|
|
++str;
|
|
if (*str == 'b' || *str == 'B') {
|
|
/* there must be at least one digit after 0b */
|
|
if (_PyLong_DigitValue[Py_CHARMASK(str[1])] >= 2) {
|
|
if (ptr)
|
|
*ptr = (char *)str;
|
|
return 0;
|
|
}
|
|
++str;
|
|
}
|
|
}
|
|
break;
|
|
}
|
|
|
|
/* catch silly bases */
|
|
if (base < 2 || base > 36) {
|
|
if (ptr)
|
|
*ptr = (char *)str;
|
|
return 0;
|
|
}
|
|
|
|
/* skip leading zeroes */
|
|
while (*str == '0')
|
|
++str;
|
|
|
|
/* base is guaranteed to be in [2, 36] at this point */
|
|
ovlimit = digitlimit[base];
|
|
|
|
/* do the conversion until non-digit character encountered */
|
|
while ((c = _PyLong_DigitValue[Py_CHARMASK(*str)]) < base) {
|
|
if (ovlimit > 0) /* no overflow check required */
|
|
result = result * base + c;
|
|
else { /* requires overflow check */
|
|
unsigned long temp_result;
|
|
|
|
if (ovlimit < 0) /* guaranteed overflow */
|
|
goto overflowed;
|
|
|
|
/* there could be an overflow */
|
|
/* check overflow just from shifting */
|
|
if (result > smallmax[base])
|
|
goto overflowed;
|
|
|
|
result *= base;
|
|
|
|
/* check overflow from the digit's value */
|
|
temp_result = result + c;
|
|
if (temp_result < result)
|
|
goto overflowed;
|
|
|
|
result = temp_result;
|
|
}
|
|
|
|
++str;
|
|
--ovlimit;
|
|
}
|
|
|
|
/* set pointer to point to the last character scanned */
|
|
if (ptr)
|
|
*ptr = (char *)str;
|
|
|
|
return result;
|
|
|
|
overflowed:
|
|
if (ptr) {
|
|
/* spool through remaining digit characters */
|
|
while (_PyLong_DigitValue[Py_CHARMASK(*str)] < base)
|
|
++str;
|
|
*ptr = (char *)str;
|
|
}
|
|
errno = ERANGE;
|
|
return (unsigned long)-1;
|
|
}
|
|
|
|
/* Checking for overflow in PyOS_strtol is a PITA; see comments
|
|
* about PY_ABS_LONG_MIN in longobject.c.
|
|
*/
|
|
#define PY_ABS_LONG_MIN (0-(unsigned long)LONG_MIN)
|
|
|
|
long
|
|
PyOS_strtol(const char *str, char **ptr, int base)
|
|
{
|
|
long result;
|
|
unsigned long uresult;
|
|
char sign;
|
|
|
|
while (*str && Py_ISSPACE(Py_CHARMASK(*str)))
|
|
str++;
|
|
|
|
sign = *str;
|
|
if (sign == '+' || sign == '-')
|
|
str++;
|
|
|
|
uresult = PyOS_strtoul(str, ptr, base);
|
|
|
|
if (uresult <= (unsigned long)LONG_MAX) {
|
|
result = (long)uresult;
|
|
if (sign == '-')
|
|
result = -result;
|
|
}
|
|
else if (sign == '-' && uresult == PY_ABS_LONG_MIN) {
|
|
result = LONG_MIN;
|
|
}
|
|
else {
|
|
errno = ERANGE;
|
|
result = LONG_MAX;
|
|
}
|
|
return result;
|
|
}
|