General-purpose bit and bit field manipulation macros.
| bitops.h | General-purpose bit and bit field manipulation macros. |
| Macros | |
| BITOPS_1 | The expression the bitops macros will use to represent an integer with the least significant bit set to one (1) and the other bits set to zero (0). |
| BV | Maps a bit number to an integer value with (only) the corresponding bit set to 1. |
| BITMASK | Maps a mask size to an integer bit mask with the corresponding number of bits set to 1. |
| BITMASK_AT | Maps a mask size and offset to an integer bit mask with the corresponding number of bits set to 1, at the specified offset. |
| BITMASK_NOT_AT | Maps a mask size and offset to an inverted integer bit mask with the corresponding number of bits set to 0, at the specified offset. |
| BITSTATES | Maps a number of bits to the number of possible states of a value with that number of bits. |
| BITMAX | Utility macro that maps a number of bits to the maximum value of an unsigned integer with that number of bits. |
| GET_BITFIELD | Maps a field size and an arbitary integer to an integer containing the bitfield with the specified size, from the least significant bits of the arbitrary integer. |
| GET_BITFIELD_AT | Maps a field size, a field offset and an arbitary integer to an integer containing the bitfield with the specified size at the specified offset in the arbitrary integer. |
| MAKE_BITFIELD_AT | Maps a field size, a field offset and an arbitary integer to an integer that has a bitfield with the specified size at the specified offset, containing bits from the arbitrary integer. |
| CLEAR_BITFIELD_AT | Maps a field size, a field offset and an arbitary integer to an integer where the bitfield with the specified size at the specified offset in the arbitrary integer has been cleared. |
| SET_BITFIELD_AT | Maps a field size, a field offset and two arbitary integers to an integer that has a bitfield with the specified size at the specified offset, containing bits from the second arbitrary integer, while the remaining bits are equal to the corresponding bits in the first arbitrary integer. |
Maps a bit number to an integer value with (only) the corresponding bit set to 1. Function-like macro.
| N | A bit number. Should be in the range 0-7 for 8-bit values and 0-15 for 16-bit values. Bit 0 is the least significant and bit 7/15 the most significant. |
An integer value with (only) the specified bit set to one (1).
Maps a mask size and offset to an integer bit mask with the corresponding number of bits set to 1, at the specified offset. Function-like macro.
| N | A mask size. Should be in the range 0-8 for 8-bit values and 0-16 for 16-bit values. |
| O | A mask offset. Should be less than or equal to (T - N), where T is the total number of bits in a value. |
An integer value with only the N bits starting at bit number O set to one (1).
Maps a mask size and offset to an inverted integer bit mask with the corresponding number of bits set to 0, at the specified offset. Function-like macro.
| N | A mask size. Should be in the range 0-8 for 8-bit values and 0-16 for 16-bit values. |
| O | A mask offset. Should be less than or equal to (T - N), where T is the total number of bits in a value. |
An integer value with only the N bits starting at bit number O set to zero (0).
Maps a number of bits to the number of possible states of a value with that number of bits. Alias of BV. Function-like macro.
| N | A number of bits. |
The number of possible states of an N-bit value (i.e. 2^*N*).
Utility macro that maps a number of bits to the maximum value of an unsigned integer with that number of bits. Alias of BITMASK. Function-like macro.
| N | A number of bits. |
| The maximum value of an *N*-bit unsigned integer (i.e. 2^*N* | 1). |
Maps a field size and an arbitary integer to an integer containing the bitfield with the specified size, from the least significant bits of the arbitrary integer. Function-like macro.
| S | A field size. Should be in the range 0-8 for 8-bit values and 0-16 for 16-bit values. |
| D | An arbitrary integer to get a bitfield from. |
An integer value containing the S lowest-significance bits of D. The remaining bits are set to zero (0).
Maps a field size, a field offset and an arbitary integer to an integer containing the bitfield with the specified size at the specified offset in the arbitrary integer. Function-like macro.
| S | A field size. Should be in the range 0-8 for 8-bit values and 0-16 for 16-bit values. |
| O | A field offset. Should be less than or equal to (T - S), where T is the total number of bits in a value. |
| D | An arbitrary integer to get an offset bitfield from. |
An integer value containing the S bits starting at bit number O in D, shifted into the lowest-significance bits. The remaining bits are set to zero (0).
Maps a field size, a field offset and an arbitary integer to an integer that has a bitfield with the specified size at the specified offset, containing bits from the arbitrary integer. Function-like macro.
| S | A field size. Should be in the range 0-8 for 8-bit values and 0-16 for 16-bit values. |
| O | A field offset. Should be less than or equal to (T - S), where T is the total number of bits in a value. |
| X | An arbitrary integer containing a bitfield value. |
An integer value containing the S lowest-significance bits of X, shifted to offset O. The remaining bits are set to zero (0).
Maps a field size, a field offset and an arbitary integer to an integer where the bitfield with the specified size at the specified offset in the arbitrary integer has been cleared. Function-like macro.
| S | A field size. Should be in the range 0-8 for 8-bit values and 0-16 for 16-bit values. |
| O | A field offset. Should be less than or equal to (T - S), where T is the total number of bits in a value. |
| D | An arbitrary integer to clear a bitfield in. |
An integer value where the S bits starting at bit number O are set to zero (0). The remaining bits have the values they have in D.
Maps a field size, a field offset and two arbitary integers to an integer that has a bitfield with the specified size at the specified offset, containing bits from the second arbitrary integer, while the remaining bits are equal to the corresponding bits in the first arbitrary integer. Function-like macro.
| S | A field size. Should be in the range 0-8 for 8-bit values and 0-16 for 16-bit values. |
| O | A field offset. Should be less than or equal to (T - S), where T is the total number of bits in a value. |
| D | An arbitrary integer to set a bitfield in. |
| X | An arbitrary integer containing a bitfield value. |
An integer value containing the S lowest-significance bits of X, shifted to offset O. The remaining bits have the values they have in D.