buffer.h

bind 9.3结合mysql数据库

 *
 */

void
isc_buffer_compact(isc_buffer_t *b);
/*
 * Compact the used region by moving the remaining region so it occurs
 * at the start of the buffer.  The used region is shrunk by the size of
 * the consumed region, and the consumed region is then made empty.
 *
 * Requires:
 *
 *	'b' is a valid buffer
 *
 * Ensures:
 *
 *	current == 0
 *
 *	The size of the used region is now equal to the size of the remaining
 *	region (as it was before the call).  The contents of the used region
 *	are those of the remaining region (as it was before the call).
 */

isc_uint8_t
isc_buffer_getuint8(isc_buffer_t *b);
/*
 * Read an unsigned 8-bit integer from 'b' and return it.
 *
 * Requires:
 *
 *	'b' is a valid buffer.
 *
 *	The length of the available region of 'b' is at least 1.
 *
 * Ensures:
 *
 *	The current pointer in 'b' is advanced by 1.
 *
 * Returns:
 *
 *	A 8-bit unsigned integer.
 */

void
isc__buffer_putuint8(isc_buffer_t *b, isc_uint8_t val);
/*
 * Store an unsigned 8-bit integer from 'val' into 'b'.
 *
 * Requires:
 *	'b' is a valid buffer.
 *
 *	The length of the unused region of 'b' is at least 1.
 *
 * Ensures:
 *	The used pointer in 'b' is advanced by 1.
 */

isc_uint16_t
isc_buffer_getuint16(isc_buffer_t *b);
/*
 * Read an unsigned 16-bit integer in network byte order from 'b', convert
 * it to host byte order, and return it.
 *
 * Requires:
 *
 *	'b' is a valid buffer.
 *
 *	The length of the available region of 'b' is at least 2.
 *
 * Ensures:
 *
 *	The current pointer in 'b' is advanced by 2.
 *
 * Returns:
 *
 *	A 16-bit unsigned integer.
 */

void
isc__buffer_putuint16(isc_buffer_t *b, isc_uint16_t val);
/*
 * Store an unsigned 16-bit integer in host byte order from 'val'
 * into 'b' in network byte order.
 *
 * Requires:
 *	'b' is a valid buffer.
 *
 *	The length of the unused region of 'b' is at least 2.
 *
 * Ensures:
 *	The used pointer in 'b' is advanced by 2.
 */

isc_uint32_t
isc_buffer_getuint32(isc_buffer_t *b);
/*
 * Read an unsigned 32-bit integer in network byte order from 'b', convert
 * it to host byte order, and return it.
 *
 * Requires:
 *
 *	'b' is a valid buffer.
 *
 *	The length of the available region of 'b' is at least 4.
 *
 * Ensures:
 *
 *	The current pointer in 'b' is advanced by 4.
 *
 * Returns:
 *
 *	A 32-bit unsigned integer.
 */

void
isc__buffer_putuint32(isc_buffer_t *b, isc_uint32_t val);
/*
 * Store an unsigned 32-bit integer in host byte order from 'val'
 * into 'b' in network byte order.
 *
 * Requires:
 *	'b' is a valid buffer.
 *
 *	The length of the unused region of 'b' is at least 4.
 *
 * Ensures:
 *	The used pointer in 'b' is advanced by 4.
 */

void
isc__buffer_putmem(isc_buffer_t *b, const unsigned char *base,
		   unsigned int length);
/*
 * Copy 'length' bytes of memory at 'base' into 'b'.
 *
 * Requires:
 *	'b' is a valid buffer.
 *
 *	'base' points to 'length' bytes of valid memory.
 *
 */

void
isc__buffer_putstr(isc_buffer_t *b, const char *source);
/*
 * Copy 'source' into 'b', not including terminating NUL.
 *
 * Requires:
 *	'b' is a valid buffer.
 *
 *	'source' to be a valid NULL terminated string.
 *
 *	strlen(source) <= isc_buffer_available(b)
 */

isc_result_t
isc_buffer_copyregion(isc_buffer_t *b, const isc_region_t *r);
/*
 * Copy the contents of 'r' into 'b'.
 *
 * Requires:
 *	'b' is a valid buffer.
 *
 *	'r' is a valid region.
 *
 * Returns:
 *
 *	ISC_R_SUCCESS
 *	ISC_R_NOSPACE			The available region of 'b' is not
 *					big enough.
 */

ISC_LANG_ENDDECLS

/*
 * Inline macro versions of the functions.  These should never be called
 * directly by an application, but will be used by the functions within
 * buffer.c.  The callers should always use "isc_buffer_*()" names, never
 * ones beginning with "isc__"
 */

/*
 * XXXDCL Something more could be done with initializing buffers that
 * point to const data.  For example, a new function, isc_buffer_initconst,
 * could be used, and a new boolean flag in the buffer structure could
 * indicate whether the buffer was initialized with that function.
 * (isc_bufer_init itself would be reprototyped to *not* have its "base"
 * parameter be const.)  Then if the boolean were true, the isc_buffer_put*
 * functions could assert a contractual requirement for a non-const buffer.
 * One drawback is that the isc_buffer_* functions (macros) that return
 * pointers would still need to return non-const pointers to avoid compiler
 * warnings, so it would be up to code that uses them to have to deal
 * with the possibility that the buffer was initialized as const --
 * a problem that they *already* have to deal with but have absolutely
 * no ability to.  With a new isc_buffer_isconst() function returning
 * true/false, they could at least assert a contractual requirement for
 * non-const buffers when needed.
 */
#define ISC__BUFFER_INIT(_b, _base, _length) \
	do { \
		union { \
			const void *	konst; \
			void *		var; \
		} _u; \
		_u.konst = (_base); \
		(_b)->base = _u.var; \
		(_b)->length = (_length); \
		(_b)->used = 0; \
		(_b)->current = 0; \
		(_b)->active = 0; \
		(_b)->mctx = NULL; \
		ISC_LINK_INIT(_b, link); \
		(_b)->magic = ISC_BUFFER_MAGIC; \
	} while (0)

#define ISC__BUFFER_INVALIDATE(_b) \
	do { \
		(_b)->magic = 0; \
		(_b)->base = NULL; \
		(_b)->length = 0; \
		(_b)->used = 0; \
		(_b)->current = 0; \
		(_b)->active = 0; \
	} while (0)

#define ISC__BUFFER_REGION(_b, _r) \
	do { \
		(_r)->base = (_b)->base; \
		(_r)->length = (_b)->length; \
	} while (0)

#define ISC__BUFFER_USEDREGION(_b, _r) \
	do { \
		(_r)->base = (_b)->base; \
		(_r)->length = (_b)->used; \
	} while (0)

#define ISC__BUFFER_AVAILABLEREGION(_b, _r) \
	do { \
		(_r)->base = isc_buffer_used(_b); \
		(_r)->length = isc_buffer_availablelength(_b); \
	} while (0)

#define ISC__BUFFER_ADD(_b, _n) \
	do { \
		(_b)->used += (_n); \
	} while (0)

#define ISC__BUFFER_SUBTRACT(_b, _n) \
	do { \
		(_b)->used -= (_n); \
		if ((_b)->current > (_b)->used) \
			(_b)->current = (_b)->used; \
		if ((_b)->active > (_b)->used) \
			(_b)->active = (_b)->used; \
	} while (0)

#define ISC__BUFFER_CLEAR(_b) \
	do { \
		(_b)->used = 0; \
		(_b)->current = 0; \
		(_b)->active = 0; \
	} while (0)

#define ISC__BUFFER_CONSUMEDREGION(_b, _r) \
	do { \
		(_r)->base = (_b)->base; \
		(_r)->length = (_b)->current; \
	} while (0)

#define ISC__BUFFER_REMAININGREGION(_b, _r) \
	do { \
		(_r)->base = isc_buffer_current(_b); \
		(_r)->length = isc_buffer_remaininglength(_b); \
	} while (0)

#define ISC__BUFFER_ACTIVEREGION(_b, _r) \
	do { \
		if ((_b)->current < (_b)->active) { \
			(_r)->base = isc_buffer_current(_b); \
			(_r)->length = isc_buffer_activelength(_b); \
		} else { \
			(_r)->base = NULL; \
			(_r)->length = 0; \
		} \
	} while (0)

#define ISC__BUFFER_SETACTIVE(_b, _n) \
	do { \
		(_b)->active = (_b)->current + (_n); \
	} while (0)

#define ISC__BUFFER_FIRST(_b) \
	do { \
		(_b)->current = 0; \
	} while (0)

#define ISC__BUFFER_FORWARD(_b, _n) \
	do { \
		(_b)->current += (_n); \
	} while (0)

#define ISC__BUFFER_BACK(_b, _n) \
	do { \
		(_b)->current -= (_n); \
	} while (0)

#define ISC__BUFFER_PUTMEM(_b, _base, _length) \
	do { \
		memcpy(isc_buffer_used(_b), (_base), (_length)); \
		(_b)->used += (_length); \
	} while (0)

#define ISC__BUFFER_PUTSTR(_b, _source) \
	do { \
		unsigned int _length; \
		unsigned char *_cp; \
		_length = strlen(_source); \
		_cp = isc_buffer_used(_b); \
		memcpy(_cp, (_source), _length); \
		(_b)->used += (_length); \
	} while (0)

#define ISC__BUFFER_PUTUINT8(_b, _val) \
	do { \
		unsigned char *_cp; \
		isc_uint8_t _val2 = (_val); \
		_cp = isc_buffer_used(_b); \
		(_b)->used++; \
		_cp[0] = _val2 & 0x00ff; \
	} while (0)

#define ISC__BUFFER_PUTUINT16(_b, _val) \
	do { \
		unsigned char *_cp; \
		isc_uint16_t _val2 = (_val); \
		_cp = isc_buffer_used(_b); \
		(_b)->used += 2; \
		_cp[0] = (unsigned char)((_val2 & 0xff00U) >> 8); \
		_cp[1] = (unsigned char)(_val2 & 0x00ffU); \
	} while (0)

#define ISC__BUFFER_PUTUINT32(_b, _val) \
	do { \
		unsigned char *_cp; \
		isc_uint32_t _val2 = (_val); \
		_cp = isc_buffer_used(_b); \
		(_b)->used += 4; \
		_cp[0] = (unsigned char)((_val2 & 0xff000000) >> 24); \
		_cp[1] = (unsigned char)((_val2 & 0x00ff0000) >> 16); \
		_cp[2] = (unsigned char)((_val2 & 0x0000ff00) >> 8); \
		_cp[3] = (unsigned char)((_val2 & 0x000000ff)); \
	} while (0)

#if defined(ISC_BUFFER_USEINLINE)
#define isc_buffer_init			ISC__BUFFER_INIT
#define isc_buffer_invalidate		ISC__BUFFER_INVALIDATE
#define isc_buffer_region		ISC__BUFFER_REGION
#define isc_buffer_usedregion		ISC__BUFFER_USEDREGION
#define isc_buffer_availableregion	ISC__BUFFER_AVAILABLEREGION
#define isc_buffer_add			ISC__BUFFER_ADD
#define isc_buffer_subtract		ISC__BUFFER_SUBTRACT
#define isc_buffer_clear		ISC__BUFFER_CLEAR
#define isc_buffer_consumedregion	ISC__BUFFER_CONSUMEDREGION
#define isc_buffer_remainingregion	ISC__BUFFER_REMAININGREGION
#define isc_buffer_activeregion		ISC__BUFFER_ACTIVEREGION
#define isc_buffer_setactive		ISC__BUFFER_SETACTIVE
#define isc_buffer_first		ISC__BUFFER_FIRST
#define isc_buffer_forward		ISC__BUFFER_FORWARD
#define isc_buffer_back			ISC__BUFFER_BACK
#define isc_buffer_putmem		ISC__BUFFER_PUTMEM
#define isc_buffer_putstr		ISC__BUFFER_PUTSTR
#define isc_buffer_putuint8		ISC__BUFFER_PUTUINT8
#define isc_buffer_putuint16		ISC__BUFFER_PUTUINT16
#define isc_buffer_putuint32		ISC__BUFFER_PUTUINT32
#else
#define isc_buffer_init			isc__buffer_init
#define isc_buffer_invalidate		isc__buffer_invalidate
#define isc_buffer_region		isc__buffer_region
#define isc_buffer_usedregion		isc__buffer_usedregion
#define isc_buffer_availableregion	isc__buffer_availableregion
#define isc_buffer_add			isc__buffer_add
#define isc_buffer_subtract		isc__buffer_subtract
#define isc_buffer_clear		isc__buffer_clear
#define isc_buffer_consumedregion	isc__buffer_consumedregion
#define isc_buffer_remainingregion	isc__buffer_remainingregion
#define isc_buffer_activeregion		isc__buffer_activeregion
#define isc_buffer_setactive		isc__buffer_setactive
#define isc_buffer_first		isc__buffer_first
#define isc_buffer_forward		isc__buffer_forward
#define isc_buffer_back			isc__buffer_back
#define isc_buffer_putmem		isc__buffer_putmem
#define isc_buffer_putstr		isc__buffer_putstr
#define isc_buffer_putuint8		isc__buffer_putuint8
#define isc_buffer_putuint16		isc__buffer_putuint16
#define isc_buffer_putuint32		isc__buffer_putuint32
#endif

#endif /* ISC_BUFFER_H */