emaildb.c

一个操作系统源代码 用于嵌入式设备 在Vc++环境下仿真 成功移植到多款处理器上

/*************************************************************************
*
* Copyright  2002 National ASIC Center, All rights Reserved
*
* FILE NAME:			emaildb.c
* PROGRAMMER:			xuanhui
* Date of Creation:		2002/10/28
* 
* DESCRIPTION: 			Database operations for the application "email".
*
* NOTE:			 		 
*						 
*
* FUNCTIONS LIST:
* -------------------------------------------------------------------------
*InitEmailDB,
*LinkEmailDB,
*DetachEmailDB,
*EmailDBReadRecord,
*EmailDBModifyRecord,
*EmailDBAddRecord,
*EmailDBDelRecord,
*EmailDBFindRecord,
*EmailDBSearchRecord,
*
* GLOBAL VARS LIST:
* 
*
**************************************************************************
*
* MODIFICATION HISTORY
*
*
* 2002/10/28	by xuanhui		Create the file
*								
*************************************************************************/
#include <string.h>
#include <sys\lmalloc.h>

#include <database\emaildb.h>
#include <database\common.h>

// 字段索引
FIELDINDEX	EmailTimeField_I[12];					// 时间一级索引表
FIELDINDEX	EmailSubjectField_I[27];				// 主题一级索引表
FIELDINDEX	EmailAddresserField_I[27];				// 发件人一级索引表
FIELDINDEX	EmailAddresseeField_I[27];				// 收件人一级索引表
FIELDINDEX	EmailTypeField[4];						// 邮件类型索引表
FIELDINDEX	EmailBoxField[4];						// 邮件所在箱型字段(收件箱、发件箱、垃圾箱)索引表

FIELDINDEXLIST	EmailDBFList[ EMAIL_FIELD_NUM ] = 
	{
		{	EMAIL_TIME_FIELD,		SINGLE_VALUE_FIELD,	12,		EmailTimeField_I,		II_LEVEL },	// 时间索引表
		{	EMAIL_SUBIECT_FIELD,	SINGLE_VALUE_FIELD,	27,		EmailSubjectField_I,    II_LEVEL },	// 主题索引表
		{	EMAIL_ADDRESSER_FIELD,	SINGLE_VALUE_FIELD,	27,		EmailAddresserField_I,  II_LEVEL },	// 发件人索引表
		{	EMAIL_TYPE_FIELD,		SINGLE_VALUE_FIELD,	4,		EmailTypeField,			I_LEVEL  },	// 邮件类型索引表
		{	EMAIL_BOX_FIELD,		SINGLE_VALUE_FIELD,	4,		EmailBoxField,			I_LEVEL  },	// 邮件所在箱型字段(收件箱、发件箱、垃圾箱)索引表
		{	EMAIL_ADDRESSEE_FIELD,	SINGLE_VALUE_FIELD,	27,		EmailAddresseeField_I,  II_LEVEL },	// 收件人索引表
		{	0,		SINGLE_VALUE_FIELD,	0,		NULL,     0  },
	};

//-------------------- Local Functions List --------------------------------------------//
//初始化一级索引表
static void InitIndexList( void );
// 将字段值加入到字段索引表
static DWORD Add2FieldIndexTbl( DBGACB *gacb, BYTE field, BYTE *value, DWORD id );
//创建新的二级索引表
static FIELDINDEX *CreateIIIndexList( FIELDINDEX *I_index_list, BYTE field );
//获取手机号码字段值的一二级索引
static void GetPhoneFieldIandIIIndex( BYTE *field_value, WORD *field_I_index, WORD *field_II_index );

/**********************************************************************/
DBGACB* InitEmailDB( DBGACB *gacb )
{
	DWORD	id = gacb->PLInfo->info.usedBlockHead;
	BYTE	i;

	// 初始化一级字段索引表
	InitIndexList();

	gacb->IFNum = EMAIL_INDEX_FIELD_NUM;
	gacb->FList = EmailDBFList;
	gacb->fieldNum = EMAIL_FIELD_NUM;

	for( i = 0; i < RECORD_FIELD_LIST_LEN; i++)
		gacb->RFList[i] = 0;

	// 构建物理模式信息
	gacb->PLInfo->info.usedBlockTail = 0;
	gacb->PLInfo->info.freeBlockHead = 0;
	gacb->PLInfo->info.usedBlockNum = 0;
	gacb->PLInfo->info.freeBlockNum = 0;

	if( id != 0 )	// 判断记录是否为空
	{
		// 记录不为空
		DBRECORDHEAD	*head_info = NULL;
		BYTE	*record = NULL, *data, *field_value;
#ifdef SIM_ON_PC
		WORD	*field;
#else
		WORD	field;
#endif
		BYTE	i;
		WORD	record_size = 0;
		DWORD	record_num = 0;
		DWORD	rv = DB_OK;

		// 逐条读取记录，建立字段索引表和记录字段表
		do
		{
			rv = GlobalReadRecord( gacb->PLInfo, id, &record );
			if( rv == DB_FREE_RECORD )	//空闲记录
				record = NULL;
			if( ( rv == DB_NO_MEM ) || ( rv == DB_ERROR ) )		
				return NULL;

			if( record == NULL )//空闲记录块
			{
				if( ( head_info = (DBRECORDHEAD *)SysLmalloc(sizeof(DBRECORDHEAD)) ) == NULL )
					return NULL;
				gacb->PLInfo->info.freeBlockHead = id;
				//初始化空闲块数目
				fseek( gacb->PLInfo->fp, id+ADDRESS_BYTE_NUM, SEEK_SET );
				fread( &record_size, SIZE_BYTE_NUM, 1, gacb->PLInfo->fp );
				record_num = (DWORD)( ( record_size + BLOCK_DATA_SIZE - 1 ) / BLOCK_DATA_SIZE );
				gacb->PLInfo->info.freeBlockNum += record_num;
				//初始化尾记录地址
				fseek( gacb->PLInfo->fp, id+ADDRESS_BYTE_NUM+SIZE_BYTE_NUM+FLAG_BYTE_NUM+NEXT_BYTE_NUM, SEEK_SET );
				fread( &head_info->prev, PREV_BYTE_NUM, 1, gacb->PLInfo->fp );
				gacb->PLInfo->info.usedBlockTail = head_info->prev;
				SysLfree(head_info);
				break;
			}else{	//有效记录块
				head_info = (DBRECORDHEAD *)record;

				record_size = head_info->size;
				record_num = (DWORD)( ( record_size + BLOCK_DATA_SIZE - 1 ) / BLOCK_DATA_SIZE );

				gacb->PLInfo->info.usedBlockTail = id;//初始化尾记录地址
				gacb->PLInfo->info.usedBlockNum += record_num;

				data = (BYTE *)(&head_info->data);
#ifdef SIM_ON_PC
				field = (WORD *)data;
#endif

				for( i = 0; i < gacb->IFNum; i++ )
				{
#ifdef SIM_ON_PC
					if( field[i] != 0 )	// 字段有字段值
					{
						field_value = data + field[i];
#else
					Bytes2Word( &field, data+(i*sizeof(WORD)) );
					if( field != 0 )	// 字段有字段值
					{
						field_value = data + field;
#endif
						// 将字段值加入到字段索引表				
						Add2FieldIndexTbl( gacb, i, field_value, id );
					}
				}
				id = head_info->next;
				SysLfree(record);
			}
		}while( id != 0 );

	}
	return gacb;
}

/**********************************************************************/
DBLACB* LinkEmailDB( DBGACB *gacb )
{
	return LinkDB( gacb );
}

/**********************************************************************/
void DetachEmailDB( DBLACB *lacb )
{
	RECORDDATA		*prev_record_data, *next_record_data;

	next_record_data = lacb->head->head;
	while( ( next_record_data != NULL ) && ( lacb->head->num != 0 ) )
	{
		prev_record_data = next_record_data;
		next_record_data++;
		if( prev_record_data->data != NULL )
			SysLfree( prev_record_data->data );
		lacb->head->num--;
	}

	SysLfree( lacb->head->head );
	SysLfree( lacb->head );
	return;
}

/**********************************************************************/
BYTE* EmailDBReadRecord( DBLACB *lacb, DWORD id )
{
	return ReadDBRecord( lacb, id );
}

/**********************************************************************/
DWORD EmailDBModifyRecord( DBLACB *lacb, DWORD id, BYTE *data, WORD dataLen )
{	
	BYTE			i;
	BYTE			*field_value, *record;
#ifdef SIM_ON_PC
	WORD			*field;
#else
	WORD			field;
#endif
	DWORD			rv = DB_OK;

	//读出修改前的数据
	rv = GlobalReadRecord( lacb->gacb->PLInfo, id, &record );
	if( rv != DB_OK )
		return DB_ERROR;

	DelRecordIndexTbl( lacb, id );

	//填充修改后的数据
	id = AddModifiedRecordData( lacb->gacb->PLInfo, id, data, dataLen, record );
	if( id == DB_ERROR )
		return DB_ERROR;

	//把修改后的记录添加大字段索引表和记录字段索引表中
#ifdef SIM_ON_PC
	field = (WORD *)data;
#endif
			
	for( i = 0; i < EMAIL_INDEX_FIELD_NUM; i++ )
	{
#ifdef SIM_ON_PC
		if( field[i] != 0 )	// 字段有字段值
		{
			field_value = data + field[i];
#else
		Bytes2Word( &field, data+(i*sizeof(WORD)) );
		if( field != 0 )	// 字段有字段值
		{
			field_value = data + field;
#endif
			// 将字段值加入到字段索引表				
			Add2FieldIndexTbl( lacb->gacb, i, field_value, id );
		}
	}
	return id;
}

/**********************************************************************/
DWORD EmailDBAddRecord( DBLACB *lacb, BYTE *data, WORD dataLen )
{
	BYTE			i;
	BYTE			*field_value;
#ifdef SIM_ON_PC
	WORD			*field;
#else
	WORD			field;
#endif
	DWORD			id = 0;

	//填充新添加的数据
	id = AddNewRecordData( lacb->gacb->PLInfo, data, dataLen );
	if( id == DB_ERROR )
		return DB_ERROR;

	//把修改后的记录添加大字段索引表和记录字段索引表中
#ifdef SIM_ON_PC
	field = (WORD *)data;
#endif
	for( i = 0; i < lacb->gacb->IFNum; i++ )
	{
#ifdef SIM_ON_PC
		if( field[i] != 0 )	// 字段有字段值
		{
			field_value = data + field[i];
#else
		Bytes2Word( &field, data+(i*sizeof(WORD)) );
		if( field != 0 )	// 字段有字段值
		{
			field_value = data + field;
#endif
			// 将字段值加入到字段索引表				
			Add2FieldIndexTbl( lacb->gacb, i, field_value, id );
		}
	}
	return id;
}

/**********************************************************************/
DWORD EmailDBDelRecord( DBLACB *lacb, DWORD id )
{
	id = GlobalDelRecord( lacb->gacb->PLInfo, id );			//在数据库中删除指定的记录
	if( ( id == DB_ERROR ) || ( id == DB_FREE_RECORD ) )
		return DB_ERROR;
		
	DelRecordIndexTbl( lacb, id );
	
	return id;
}

/**********************************************************************/
//在指定数据库中查找与指定字段匹配(完全匹配/部分匹配)的记录(精确查找)
LOCALSEARCHLIST* EmailDBFindRecord( DBLACB *lacb, BYTE field, BYTE *data, BYTE mode )
{	
	WORD				i, k = 0;
	FIELDINDEXLIST		*list;		//字段索引表	
	FIELDINDEX			*I_index_list, *II_index_list;	//一、二级索引表
	WORD				field_I_index[PY_MAX_NUM], field_II_index[PY_MAX_NUM];//字段一二级索引值
	BYTE				PY_num = 0;
	RECORDINDEX			*local_search_list = NULL;
	RECORDDATA			*record_data_head;
	DWORD				read_rv = DB_OK;

	//验证字段的有效性
	if( field < 0 || field > ( EMAIL_INDEX_FIELD_NUM - 1) )
		return NULL;
	
	//验证查找模式的有效性
	if( ( mode != PRECISE_FULL_MATCH ) && ( mode != PRECISE_PART_MATCH ) && ( mode != GLOBAL_SEARCH ) )
		return NULL;

	//字段的查找
	if( data == NULL )//验证字段值的有效性
		return NULL;

	list = lacb->gacb->FList;
	I_index_list = list[field].head;//找到相符的一级字段索引表
	
	//申请局部查找表
	if( ( lacb->head = (LOCALSEARCHLIST *)SysLmalloc( sizeof(LOCALSEARCHLIST) ) ) == NULL )	
		return NULL;
	lacb->head->num = 0;
	lacb->head->head = NULL;

	switch( field )	//获取关键字的一二级索引