Function bitmapTestBit

app/redis-6.2.6/src/cluster.c:3807–3811

Test bit 'pos' in a generic bitmap. Return 1 if the bit is set, * otherwise 0. */

/* Test bit 'pos' in a generic bitmap. Return 1 if the bit is set,
 * otherwise 0. */
int bitmapTestBit(unsigned char *bitmap, int pos) {
    off_t byte = pos/8;
    int bit = pos&7;
    return (bitmap[byte] & (1<<bit)) != 0;
}

/* Set the bit at position 'pos' in a bitmap. */
void bitmapSetBit(unsigned char *bitmap, int pos) {