Function memtoll

app/redis-6.2.6/src/util.c:195–245

Convert a string representing an amount of memory into the number of * bytes, so for instance memtoll("1Gb") will return 1073741824 that is * (1024*1024*1024). * * On parsing error, if *err is not NULL, it's set to 1, otherwise it's * set to 0. On error the function return value is 0, regardless of the * fact 'err' is NULL or not. */

 * set to 0. On error the function return value is 0, regardless of the
 * fact 'err' is NULL or not. */
long long memtoll(const char *p, int *err) {
    const char *u;
    char buf[128];
    long mul; /* unit multiplier */
    long long val;
    unsigned int digits;

    if (err) *err = 0;

    /* Search the first non digit character. */
    u = p;
    if (*u == '-') u++;
    while(*u && isdigit(*u)) u++;
    if (*u == '\0' || !strcasecmp(u,"b")) {
        mul = 1;
    } else if (!strcasecmp(u,"k")) {
        mul = 1000;
    } else if (!strcasecmp(u,"kb")) {
        mul = 1024;
    } else if (!strcasecmp(u,"m")) {
        mul = 1000*1000;
    } else if (!strcasecmp(u,"mb")) {
        mul = 1024*1024;
    } else if (!strcasecmp(u,"g")) {
        mul = 1000L*1000*1000;
    } else if (!strcasecmp(u,"gb")) {
        mul = 1024L*1024*1024;
    } else {
        if (err) *err = 1;
        return 0;
    }

    /* Copy the digits into a buffer, we'll use strtoll() to convert
     * the digit (without the unit) into a number. */
    digits = u-p;
    if (digits >= sizeof(buf)) {
        if (err) *err = 1;
        return 0;
    }
    memcpy(buf,p,digits);
    buf[digits] = '\0';

    char *endptr;
    errno = 0;
    val = strtoll(buf,&endptr,10);
    if ((val == 0 && errno == EINVAL) || *endptr != '\0') {
        if (err) *err = 1;
        return 0;
    }
    return val*mul;
}

/* Search a memory buffer for any set of bytes, like strpbrk().
 * Returns pointer to first found char or NULL.