cscg22-gearboy

CSCG 2022 Challenge 'Gearboy'
git clone https://git.sinitax.com/sinitax/cscg22-gearboy
Log | Files | Refs | sfeed.txt

atol.c (580B)

      1#include <stdint.h>
      2#include <stdbool.h>
      3
      4inline bool _isdigit(char c) {
      5    return ((uint8_t)((uint8_t)c - '0') < 10u) ? true : false;
      6}
      7
      8long atol(const char *s) {
      9    bool sign = false;
     10    long n;
     11
     12    const uint8_t * pc = (const uint8_t *)s;
     13
     14    for(; ((*pc == ' ') || (*pc == '\t') || (*pc == '\n')); ++pc);
     15    
     16    switch(*pc) {
     17        case '-':
     18            sign = true;
     19            /* and fall through */
     20        case '+':
     21            ++pc;
     22            break;
     23    }
     24    
     25    for(n = 0; _isdigit(*pc); ++pc) n = 10 * n + (*pc - '0');
     26
     27    return (sign == 0 ? n : -n);
     28}