c_cpp Ç语言创建0〜48的8个索引

Posted 2021-05-14

int
java_hashCode(const char *str)
{
    int hash = 0;
    for (int i = 0; i < strlen(str); i++) {
        hash = 31 * hash + str[i];
    }
    return hash;
}

char *
concat(const char *s1, const char *s2)
{
    const size_t len1 = strlen(s1);
    const size_t len2 = strlen(s2);
    char *result = malloc(len1+len2+1);
    memcpy(result, s1, len1);
    memcpy(result+len1, s2, len2+1);
    return result;
}

struct IndexsResult
getSha1KeyIndexs(const char *product,
                 const char *version,
                 const char *deviceID,
                 const char *timeStamp)
{
    struct IndexsResult result = {{0}};
    char *temp = malloc(strlen(product) + 1);
    strcpy(temp, product);
    
    char *temp1 = concat(temp, version);
    char *temp2 = concat(temp1, deviceID);
    char *data = concat(temp2, timeStamp);
    int hash = java_hashCode(data);
    hash = hash & 0x7FFFFFFF;
    free(temp);
    free(temp1);
    free(temp2);
    free(data);
    
    for(int i=0; i<8; i++) {
        int index = (int)(hash / (int)pow(10, i)) % 48;
        result.indexs[i] = index;
    }
    return result;
}