~drizzle-trunk/drizzle/development

/******************************************************

The dynamically allocated array

(c) 1996 Innobase Oy

Created 2/5/1996 Heikki Tuuri

*******************************************************/

#ifndef dyn0dyn_h

#define dyn0dyn_h

#include "univ.i"

#include "ut0lst.h"

#include "mem0mem.h"

typedef struct dyn_block_struct		dyn_block_t;

typedef dyn_block_t			dyn_array_t;

/* This is the initial 'payload' size of a dynamic array;

this must be > MLOG_BUF_MARGIN + 30! */

#define	DYN_ARRAY_DATA_SIZE	512

/*************************************************************************

Initializes a dynamic array. */

UNIV_INLINE

dyn_array_t*

dyn_array_create(

/*=============*/

				/* out: initialized dyn array */

	dyn_array_t*	arr);	/* in: pointer to a memory buffer of

				size sizeof(dyn_array_t) */

/****************************************************************

Frees a dynamic array. */

UNIV_INLINE

void

dyn_array_free(

/*===========*/

	dyn_array_t*	arr);	/* in: dyn array */

/*************************************************************************

Makes room on top of a dyn array and returns a pointer to a buffer in it.

After copying the elements, the caller must close the buffer using

dyn_array_close. */

UNIV_INLINE

byte*

dyn_array_open(

/*===========*/

				/* out: pointer to the buffer */

	dyn_array_t*	arr,	/* in: dynamic array */

	ulint		size);	/* in: size in bytes of the buffer; MUST be

				smaller than DYN_ARRAY_DATA_SIZE! */

/*************************************************************************

Closes the buffer returned by dyn_array_open. */

UNIV_INLINE

void

dyn_array_close(

/*============*/

	dyn_array_t*	arr,	/* in: dynamic array */

	byte*		ptr);	/* in: buffer space from ptr up was not used */

/*************************************************************************

Makes room on top of a dyn array and returns a pointer to

the added element. The caller must copy the element to

the pointer returned. */

UNIV_INLINE

void*

dyn_array_push(

/*===========*/

				/* out: pointer to the element */

	dyn_array_t*	arr,	/* in: dynamic array */

	ulint		size);	/* in: size in bytes of the element */

/****************************************************************

Returns pointer to an element in dyn array. */

UNIV_INLINE

void*

dyn_array_get_element(

/*==================*/

				/* out: pointer to element */

	dyn_array_t*	arr,	/* in: dyn array */

	ulint		pos);	/* in: position of element as bytes

				from array start */

/****************************************************************

Returns the size of stored data in a dyn array. */

UNIV_INLINE

ulint

dyn_array_get_data_size(

/*====================*/

				/* out: data size in bytes */

	dyn_array_t*	arr);	/* in: dyn array */

/****************************************************************

Gets the first block in a dyn array. */

UNIV_INLINE

dyn_block_t*

dyn_array_get_first_block(

/*======================*/

	dyn_array_t*	arr);	/* in: dyn array */

/****************************************************************

Gets the last block in a dyn array. */

UNIV_INLINE

dyn_block_t*

dyn_array_get_last_block(

/*=====================*/

	dyn_array_t*	arr);	/* in: dyn array */

/************************************************************************

Gets the next block in a dyn array. */

UNIV_INLINE

dyn_block_t*

dyn_array_get_next_block(

/*=====================*/

				/* out: pointer to next, NULL if end of list */

	dyn_array_t*	arr,	/* in: dyn array */

	dyn_block_t*	block);	/* in: dyn array block */

/************************************************************************

Gets the number of used bytes in a dyn array block. */

UNIV_INLINE

ulint

dyn_block_get_used(

/*===============*/

				/* out: number of bytes used */

	dyn_block_t*	block);	/* in: dyn array block */

/************************************************************************

Gets pointer to the start of data in a dyn array block. */

UNIV_INLINE

byte*

dyn_block_get_data(

/*===============*/

				/* out: pointer to data */

	dyn_block_t*	block);	/* in: dyn array block */

/************************************************************

Pushes n bytes to a dyn array. */

UNIV_INLINE

void

dyn_push_string(

/*============*/

	dyn_array_t*	arr,	/* in: dyn array */

	const byte*	str,	/* in: string to write */

	ulint		len);	/* in: string length */

/*#################################################################*/

/* NOTE! Do not use the fields of the struct directly: the definition

appears here only for the compiler to know its size! */

struct dyn_block_struct{

	mem_heap_t*	heap;	/* in the first block this is != NULL

				if dynamic allocation has been needed */

	ulint		used;	/* number of data bytes used in this block */

	byte		data[DYN_ARRAY_DATA_SIZE];

				/* storage for array elements */

	UT_LIST_BASE_NODE_T(dyn_block_t) base;

				/* linear list of dyn blocks: this node is

				used only in the first block */

	UT_LIST_NODE_T(dyn_block_t) list;

				/* linear list node: used in all blocks */

#ifdef UNIV_DEBUG

	ulint		buf_end;/* only in the debug version: if dyn array is

				opened, this is the buffer end offset, else

				this is 0 */

	ulint		magic_n;

#endif

};

#ifndef UNIV_NONINL

#include "dyn0dyn.ic"

#endif

#endif