ntfs/libntfs/bitmap.c

49  * ntfs_bit_set - set a bit in a field of bits
51  * @bit:	bit to set
52  * @new_value:	value to set bit to (0 or 1)
54  * Set the bit @bit in the @bitmap to @new_value. Ignore all errors.
56 void ntfs_bit_set(u8 *bitmap, const u64 bit, const u8 new_value)
61 		bitmap[bit >> 3] &= ~(1 << (bit & 7));
63 		bitmap[bit >> 3] |= (1 << (bit & 7));
67  * ntfs_bit_get - get value of a bit in a field of bits
69  * @bit:	bit to get
71  * Get and return the value of the bit @bit in @bitmap (0 or 1).
74 char ntfs_bit_get(const u8 *bitmap, const u64 bit)
78 	return (bitmap[bit >> 3] >> (bit & 7)) & 1;
82  * ntfs_bit_get_and_set - get value of a bit in a field of bits and set it
84  * @bit:	bit to get/set
85  * @new_value:	value to set bit to (0 or 1)
87  * Return the value of the bit @bit and set it to @new_value (0 or 1).
90 char ntfs_bit_get_and_set(u8 *bitmap, const u64 bit, const u8 new_value)
96 	shift = bit & 7;
97 	old_bit = (bitmap[bit >> 3] >> shift) & 1;
99 		bitmap[bit >> 3] ^= 1 << shift;
106  * @start_bit:	first bit to set
110  * Set @count bits starting at bit @start_bit in the bitmap described by the
120 	int bit, firstbyte, lastbyte, lastbyte_pos, tmp, ret = -1;
129 	bit = start_bit & 7;
130 	if (bit)
136 	bufsize = ((count - (bit ? 8 - bit : 0) + 7) >> 3) + firstbyte;
148 	if (bit) {
157 		while ((bit & 7) && count--) {
159 				*buf |= 1 << bit++;
161 				*buf &= ~(1 << bit++);
170 	bit = count & 7;
173 		if (count > 0 && bit) {
199 				while (bit && count--) {
201 						*lastbyte_buf |= 1 << --bit;
203 						*lastbyte_buf &= ~(1 << --bit);
206 				bit = 0;
260  * @start_bit:	first bit to set
263  * Set @count bits starting at bit @start_bit in the bitmap described by the
272 	ntfs_log_enter("Set from bit %lld, count %lld\n",
282  * @start_bit:	first bit to clear
285  * Clear @count bits starting at bit @start_bit in the bitmap described by the
294 	ntfs_log_enter("Clear from bit %lld, count %lld\n",