third_party/ulib/musl/src/misc/a64l.c

#include <stdint.h>
#include <stdlib.h>
#include <string.h>

static const char digits[] = "./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";

long a64l(const char* s) {
    int e;
    uint32_t x = 0;
    for (e = 0; e < 36 && *s; e += 6, s++)
        x |= (strchr(digits, *s) - digits) << e;
    return x;
}

char* l64a(long x0) {
    static char s[7];
    char* p;
    uint32_t x = x0;
    for (p = s; x; p++, x >>= 6)
        *p = digits[x & 63];
    *p = 0;
    return s;
}