jsix/src/libraries/libc/j6libc/strtox_main.c

/* _PDCLIB_strtox_main( const char * *, int, uintmax_t, uintmax_t, int )

   This file is part of the Public Domain C Library (PDCLib).
   Permission is granted to use, modify, and / or redistribute at will.
*/

#include <ctype.h>
#include <errno.h>
#include <string.h>
#include <stdint.h>

uintmax_t _PDCLIB_strtox_main( const char ** p, unsigned int base, uintmax_t error, uintmax_t limval, int limdigit, char * sign )
{
    uintmax_t rc = 0;
    int digit = -1;
    const char * x;
    while ( ( x = memchr( _PDCLIB_digits, tolower(**p), base ) ) != NULL )
    {
        digit = x - _PDCLIB_digits;
        if ( ( rc < limval ) || ( ( rc == limval ) && ( digit <= limdigit ) ) )
        {
            rc = rc * base + (unsigned)digit;
            ++(*p);
        }
        else
        {
            errno = ERANGE;
            /* TODO: Only if endptr != NULL - but do we really want *another* parameter? */
            /* TODO: Earlier version was missing tolower() here but was not caught by tests */
            while ( memchr( _PDCLIB_digits, tolower(**p), base ) != NULL ) ++(*p);
            /* TODO: This is ugly, but keeps caller from negating the error value */
            *sign = '+';
            return error;
        }
    }
    if ( digit == -1 )
    {
        *p = NULL;
        return 0;
    }
    return rc;
}