ref: f7685e70ed2dfe601aba35916c3ce8e6281d68b6
dir: /lib/c/atoi.c/
#include <ctype.h> #include <stdlib.h> #undef atoi int atoi(const char *s) { int n, sign = -1; while (isspace(*s)) ++s; switch (*s) { case '-': sign = 1; case '+': ++s; } /* Compute n as a negative number to avoid overflow on INT_MIN */ for (n = 0; isdigit(*s); ++s) n = 10*n - (*s - '0'); return sign * n; }