ref: 5c448c618a89ab8933838da1b5b97ed7c4a42e08
dir: /sys/src/ape/lib/ap/gen/strtoll.c/
#include <stdlib.h> #include <stdint.h> #include <limits.h> #include <errno.h> #define VLONG_MAX ~(1LL<<63) #define VLONG_MIN (1LL<<63) long long strtoll(char *nptr, char **endptr, int base) { char *p; long long n, nn, m; int c, ovfl, v, neg, ndig; p = nptr; neg = 0; n = 0; ndig = 0; ovfl = 0; /* * White space */ for(;; p++) { switch(*p) { case ' ': case '\t': case '\n': case '\f': case '\r': case '\v': continue; } break; } /* * Sign */ if(*p=='-' || *p=='+') if(*p++ == '-') neg = 1; /* * Base */ if(base==0){ base = 10; if(*p == '0') { base = 8; if(p[1]=='x' || p[1]=='X') { p += 2; base = 16; } } } else if(base==16 && *p=='0') { if(p[1]=='x' || p[1]=='X') p += 2; } else if(base<0 || 36<base) goto Return; /* * Non-empty sequence of digits */ m = VLONG_MAX/base; for(;; p++,ndig++) { c = *p; v = base; if('0'<=c && c<='9') v = c - '0'; else if('a'<=c && c<='z') v = c - 'a' + 10; else if('A'<=c && c<='Z') v = c - 'A' + 10; if(v >= base) break; if(n > m) ovfl = 1; nn = n*base + v; if(nn < n) ovfl = 1; n = nn; } Return: if(ndig == 0) p = nptr; if(endptr) *endptr = p; if(ovfl){ errno = ERANGE; if(neg) return VLONG_MIN; return VLONG_MAX; } if(neg) return -n; return n; } intmax_t strtoimax(char *nptr, char **endptr, int base) { return strtoll(nptr, endptr, base); }