+++ /dev/null
-#ifndef _URCU_RCUJA_BITFIELD_H
-#define _URCU_RCUJA_BITFIELD_H
-
-/*
- * Bitfields read/write functions.
- *
- * Copyright 2010 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in
- * all copies or substantial portions of the Software.
- */
-
-#include <stdint.h> /* C99 5.2.4.2 Numerical limits */
-#include <limits.h> /* C99 5.2.4.2 Numerical limits */
-#include <assert.h>
-#include "endian.h" /* Non-standard BIG_ENDIAN, LITTLE_ENDIAN, BYTE_ORDER */
-
-/* We can't shift a int from 32 bit, >> 32 and << 32 on int is undefined */
-#define _ja_piecewise_rshift(_v, _shift) \
-({ \
- typeof(_v) ___v = (_v); \
- typeof(_shift) ___shift = (_shift); \
- unsigned long sb = (___shift) / (sizeof(___v) * CHAR_BIT - 1); \
- unsigned long final = (___shift) % (sizeof(___v) * CHAR_BIT - 1); \
- \
- for (; sb; sb--) \
- ___v >>= sizeof(___v) * CHAR_BIT - 1; \
- ___v >>= final; \
-})
-
-#define _ja_piecewise_lshift(_v, _shift) \
-({ \
- typeof(_v) ___v = (_v); \
- typeof(_shift) ___shift = (_shift); \
- unsigned long sb = (___shift) / (sizeof(___v) * CHAR_BIT - 1); \
- unsigned long final = (___shift) % (sizeof(___v) * CHAR_BIT - 1); \
- \
- for (; sb; sb--) \
- ___v <<= sizeof(___v) * CHAR_BIT - 1; \
- ___v <<= final; \
-})
-
-#define _ja_is_signed_type(type) (((type)(-1)) < 0)
-
-#define _ja_unsigned_cast(type, v) \
-({ \
- (sizeof(v) < sizeof(type)) ? \
- ((type) (v)) & (~(~(type) 0 << (sizeof(v) * CHAR_BIT))) : \
- (type) (v); \
-})
-
-/*
- * ja_bitfield_write - write integer to a bitfield in native endianness
- *
- * Save integer to the bitfield, which starts at the "start" bit, has "len"
- * bits.
- * The inside of a bitfield is from high bits to low bits.
- * Uses native endianness.
- * For unsigned "v", pad MSB with 0 if bitfield is larger than v.
- * For signed "v", sign-extend v if bitfield is larger than v.
- *
- * On little endian, bytes are placed from the less significant to the most
- * significant. Also, consecutive bitfields are placed from lower bits to higher
- * bits.
- *
- * On big endian, bytes are places from most significant to less significant.
- * Also, consecutive bitfields are placed from higher to lower bits.
- */
-
-#define _ja_bitfield_write_le(_ptr, type, _start, _length, _v) \
-do { \
- typeof(_v) __v = (_v); \
- type *__ptr = (void *) (_ptr); \
- unsigned long __start = (_start), __length = (_length); \
- type mask, cmask; \
- unsigned long ts = sizeof(type) * CHAR_BIT; /* type size */ \
- unsigned long start_unit, end_unit, this_unit; \
- unsigned long end, cshift; /* cshift is "complement shift" */ \
- \
- if (!__length) \
- break; \
- \
- end = __start + __length; \
- start_unit = __start / ts; \
- end_unit = (end + (ts - 1)) / ts; \
- \
- /* Trim v high bits */ \
- if (__length < sizeof(__v) * CHAR_BIT) \
- __v &= ~((~(typeof(__v)) 0) << __length); \
- \
- /* We can now append v with a simple "or", shift it piece-wise */ \
- this_unit = start_unit; \
- if (start_unit == end_unit - 1) { \
- mask = ~((~(type) 0) << (__start % ts)); \
- if (end % ts) \
- mask |= (~(type) 0) << (end % ts); \
- cmask = (type) __v << (__start % ts); \
- cmask &= ~mask; \
- __ptr[this_unit] &= mask; \
- __ptr[this_unit] |= cmask; \
- break; \
- } \
- if (__start % ts) { \
- cshift = __start % ts; \
- mask = ~((~(type) 0) << cshift); \
- cmask = (type) __v << cshift; \
- cmask &= ~mask; \
- __ptr[this_unit] &= mask; \
- __ptr[this_unit] |= cmask; \
- __v = _ja_piecewise_rshift(__v, ts - cshift); \
- __start += ts - cshift; \
- this_unit++; \
- } \
- for (; this_unit < end_unit - 1; this_unit++) { \
- __ptr[this_unit] = (type) __v; \
- __v = _ja_piecewise_rshift(__v, ts); \
- __start += ts; \
- } \
- if (end % ts) { \
- mask = (~(type) 0) << (end % ts); \
- cmask = (type) __v; \
- cmask &= ~mask; \
- __ptr[this_unit] &= mask; \
- __ptr[this_unit] |= cmask; \
- } else \
- __ptr[this_unit] = (type) __v; \
-} while (0)
-
-#define _ja_bitfield_write_be(_ptr, type, _start, _length, _v) \
-do { \
- typeof(_v) __v = (_v); \
- type *__ptr = (void *) (_ptr); \
- unsigned long __start = (_start), __length = (_length); \
- type mask, cmask; \
- unsigned long ts = sizeof(type) * CHAR_BIT; /* type size */ \
- unsigned long start_unit, end_unit, this_unit; \
- unsigned long end, cshift; /* cshift is "complement shift" */ \
- \
- if (!__length) \
- break; \
- \
- end = __start + __length; \
- start_unit = __start / ts; \
- end_unit = (end + (ts - 1)) / ts; \
- \
- /* Trim v high bits */ \
- if (__length < sizeof(__v) * CHAR_BIT) \
- __v &= ~((~(typeof(__v)) 0) << __length); \
- \
- /* We can now append v with a simple "or", shift it piece-wise */ \
- this_unit = end_unit - 1; \
- if (start_unit == end_unit - 1) { \
- mask = ~((~(type) 0) << ((ts - (end % ts)) % ts)); \
- if (__start % ts) \
- mask |= (~((type) 0)) << (ts - (__start % ts)); \
- cmask = (type) __v << ((ts - (end % ts)) % ts); \
- cmask &= ~mask; \
- __ptr[this_unit] &= mask; \
- __ptr[this_unit] |= cmask; \
- break; \
- } \
- if (end % ts) { \
- cshift = end % ts; \
- mask = ~((~(type) 0) << (ts - cshift)); \
- cmask = (type) __v << (ts - cshift); \
- cmask &= ~mask; \
- __ptr[this_unit] &= mask; \
- __ptr[this_unit] |= cmask; \
- __v = _ja_piecewise_rshift(__v, cshift); \
- end -= cshift; \
- this_unit--; \
- } \
- for (; (long) this_unit >= (long) start_unit + 1; this_unit--) { \
- __ptr[this_unit] = (type) __v; \
- __v = _ja_piecewise_rshift(__v, ts); \
- end -= ts; \
- } \
- if (__start % ts) { \
- mask = (~(type) 0) << (ts - (__start % ts)); \
- cmask = (type) __v; \
- cmask &= ~mask; \
- __ptr[this_unit] &= mask; \
- __ptr[this_unit] |= cmask; \
- } else \
- __ptr[this_unit] = (type) __v; \
-} while (0)
-
-/*
- * ja_bitfield_write - write integer to a bitfield in native endianness
- * ja_bitfield_write_le - write integer to a bitfield in little endian
- * ja_bitfield_write_be - write integer to a bitfield in big endian
- */
-
-#if (BYTE_ORDER == LITTLE_ENDIAN)
-
-#define ja_bitfield_write(ptr, type, _start, _length, _v) \
- _ja_bitfield_write_le(ptr, type, _start, _length, _v)
-
-#define ja_bitfield_write_le(ptr, type, _start, _length, _v) \
- _ja_bitfield_write_le(ptr, type, _start, _length, _v)
-
-#define ja_bitfield_write_be(ptr, type, _start, _length, _v) \
- _ja_bitfield_write_be(ptr, unsigned char, _start, _length, _v)
-
-#elif (BYTE_ORDER == BIG_ENDIAN)
-
-#define ja_bitfield_write(ptr, type, _start, _length, _v) \
- _ja_bitfield_write_be(ptr, type, _start, _length, _v)
-
-#define ja_bitfield_write_le(ptr, type, _start, _length, _v) \
- _ja_bitfield_write_le(ptr, unsigned char, _start, _length, _v)
-
-#define ja_bitfield_write_be(ptr, type, _start, _length, _v) \
- _ja_bitfield_write_be(ptr, type, _start, _length, _v)
-
-#else /* (BYTE_ORDER == PDP_ENDIAN) */
-
-#error "Byte order not supported"
-
-#endif
-
-#define _ja_bitfield_read_le(_ptr, type, _start, _length, _vptr) \
-do { \
- typeof(*(_vptr)) *__vptr = (_vptr); \
- typeof(*__vptr) __v; \
- type *__ptr = (void *) (_ptr); \
- unsigned long __start = (_start), __length = (_length); \
- type mask, cmask; \
- unsigned long ts = sizeof(type) * CHAR_BIT; /* type size */ \
- unsigned long start_unit, end_unit, this_unit; \
- unsigned long end, cshift; /* cshift is "complement shift" */ \
- \
- if (!__length) { \
- *__vptr = 0; \
- break; \
- } \
- \
- end = __start + __length; \
- start_unit = __start / ts; \
- end_unit = (end + (ts - 1)) / ts; \
- \
- this_unit = end_unit - 1; \
- if (_ja_is_signed_type(typeof(__v)) \
- && (__ptr[this_unit] & ((type) 1 << ((end % ts ? : ts) - 1)))) \
- __v = ~(typeof(__v)) 0; \
- else \
- __v = 0; \
- if (start_unit == end_unit - 1) { \
- cmask = __ptr[this_unit]; \
- cmask >>= (__start % ts); \
- if ((end - __start) % ts) { \
- mask = ~((~(type) 0) << (end - __start)); \
- cmask &= mask; \
- } \
- __v = _ja_piecewise_lshift(__v, end - __start); \
- __v |= _ja_unsigned_cast(typeof(__v), cmask); \
- *__vptr = __v; \
- break; \
- } \
- if (end % ts) { \
- cshift = end % ts; \
- mask = ~((~(type) 0) << cshift); \
- cmask = __ptr[this_unit]; \
- cmask &= mask; \
- __v = _ja_piecewise_lshift(__v, cshift); \
- __v |= _ja_unsigned_cast(typeof(__v), cmask); \
- end -= cshift; \
- this_unit--; \
- } \
- for (; (long) this_unit >= (long) start_unit + 1; this_unit--) { \
- __v = _ja_piecewise_lshift(__v, ts); \
- __v |= _ja_unsigned_cast(typeof(__v), __ptr[this_unit]);\
- end -= ts; \
- } \
- if (__start % ts) { \
- mask = ~((~(type) 0) << (ts - (__start % ts))); \
- cmask = __ptr[this_unit]; \
- cmask >>= (__start % ts); \
- cmask &= mask; \
- __v = _ja_piecewise_lshift(__v, ts - (__start % ts)); \
- __v |= _ja_unsigned_cast(typeof(__v), cmask); \
- } else { \
- __v = _ja_piecewise_lshift(__v, ts); \
- __v |= _ja_unsigned_cast(typeof(__v), __ptr[this_unit]);\
- } \
- *__vptr = __v; \
-} while (0)
-
-#define _ja_bitfield_read_be(_ptr, type, _start, _length, _vptr) \
-do { \
- typeof(*(_vptr)) *__vptr = (_vptr); \
- typeof(*__vptr) __v; \
- type *__ptr = (void *) (_ptr); \
- unsigned long __start = (_start), __length = (_length); \
- type mask, cmask; \
- unsigned long ts = sizeof(type) * CHAR_BIT; /* type size */ \
- unsigned long start_unit, end_unit, this_unit; \
- unsigned long end, cshift; /* cshift is "complement shift" */ \
- \
- if (!__length) { \
- *__vptr = 0; \
- break; \
- } \
- \
- end = __start + __length; \
- start_unit = __start / ts; \
- end_unit = (end + (ts - 1)) / ts; \
- \
- this_unit = start_unit; \
- if (_ja_is_signed_type(typeof(__v)) \
- && (__ptr[this_unit] & ((type) 1 << (ts - (__start % ts) - 1)))) \
- __v = ~(typeof(__v)) 0; \
- else \
- __v = 0; \
- if (start_unit == end_unit - 1) { \
- cmask = __ptr[this_unit]; \
- cmask >>= (ts - (end % ts)) % ts; \
- if ((end - __start) % ts) { \
- mask = ~((~(type) 0) << (end - __start)); \
- cmask &= mask; \
- } \
- __v = _ja_piecewise_lshift(__v, end - __start); \
- __v |= _ja_unsigned_cast(typeof(__v), cmask); \
- *__vptr = __v; \
- break; \
- } \
- if (__start % ts) { \
- cshift = __start % ts; \
- mask = ~((~(type) 0) << (ts - cshift)); \
- cmask = __ptr[this_unit]; \
- cmask &= mask; \
- __v = _ja_piecewise_lshift(__v, ts - cshift); \
- __v |= _ja_unsigned_cast(typeof(__v), cmask); \
- __start += ts - cshift; \
- this_unit++; \
- } \
- for (; this_unit < end_unit - 1; this_unit++) { \
- __v = _ja_piecewise_lshift(__v, ts); \
- __v |= _ja_unsigned_cast(typeof(__v), __ptr[this_unit]);\
- __start += ts; \
- } \
- if (end % ts) { \
- mask = ~((~(type) 0) << (end % ts)); \
- cmask = __ptr[this_unit]; \
- cmask >>= ts - (end % ts); \
- cmask &= mask; \
- __v = _ja_piecewise_lshift(__v, end % ts); \
- __v |= _ja_unsigned_cast(typeof(__v), cmask); \
- } else { \
- __v = _ja_piecewise_lshift(__v, ts); \
- __v |= _ja_unsigned_cast(typeof(__v), __ptr[this_unit]);\
- } \
- *__vptr = __v; \
-} while (0)
-
-/*
- * ja_bitfield_read - read integer from a bitfield in native endianness
- * ja_bitfield_read_le - read integer from a bitfield in little endian
- * ja_bitfield_read_be - read integer from a bitfield in big endian
- */
-
-#if (BYTE_ORDER == LITTLE_ENDIAN)
-
-#define ja_bitfield_read(_ptr, type, _start, _length, _vptr) \
- _ja_bitfield_read_le(_ptr, type, _start, _length, _vptr)
-
-#define ja_bitfield_read_le(_ptr, type, _start, _length, _vptr) \
- _ja_bitfield_read_le(_ptr, type, _start, _length, _vptr)
-
-#define ja_bitfield_read_be(_ptr, type, _start, _length, _vptr) \
- _ja_bitfield_read_be(_ptr, unsigned char, _start, _length, _vptr)
-
-#elif (BYTE_ORDER == BIG_ENDIAN)
-
-#define ja_bitfield_read(_ptr, type, _start, _length, _vptr) \
- _ja_bitfield_read_be(_ptr, type, _start, _length, _vptr)
-
-#define ja_bitfield_read_le(_ptr, type, _start, _length, _vptr) \
- _ja_bitfield_read_le(_ptr, unsigned char, _start, _length, _vptr)
-
-#define ja_bitfield_read_be(_ptr, type, _start, _length, _vptr) \
- _ja_bitfield_read_be(_ptr, type, _start, _length, _vptr)
-
-#else /* (BYTE_ORDER == PDP_ENDIAN) */
-
-#error "Byte order not supported"
-
-#endif
-
-#endif /* _URCU_RCUJA_BITFIELD_H */
projects / userspace-rcu.git / commitdiff
