c++ mysqlhelper 数据库访问层功能封装

/**************************************************** Copyright (C), 2010-2014, Jovision Tech. Co., Ltd. File name : mysqlhelper.h Author : loong Version : 1.0 Date : 2014-03-07 Description : 数据库存储业务模块 Function List: 1.dba_connect : 连接数据库 2.dba_disconnect : 断开数据库连接 3.dba_executeprocedure : 执行存储过程 4.dba_queryresult : 获取查询结果集 5.dba_nextrow : 结果集的下一行 6.dba_seekrow : 转到结果集某一行 7.dba_getfieldcount : 获取结果集的列数 8.dba_getfieldname : 获取列名称 9.dba_getfieldvalue : 获取列值 10.dba_getfieldvaluebyname : 根据列名获取列值 11.dba_findfieldname : 查找列名称 12.dba_freeresult : 释放结果集 14.dba_geterrormsg : 获取错误信息 ****************************************************/ #ifndef VC_EXTRALEAN #define VC_EXTRALEAN // 从 Windows 头中排除极少使用的资料 #endif #include <Windows.h> #include <stdlib.h> #include <string.h> #include <stdarg.h> #include <stdio.h> #include <errno.h> #include "mysqlhelper.h" /*连接数据库*/ int dba_connect(DBA *dba, const char *host, const char *user, const char * passwd, const char * db, unsigned int port) { if(dba == NULL) return MYSQL_ERROR; if(host == NULL || user == NULL || passwd == NULL || db == NULL || port < 1) { return MYSQL_ERROR; } #ifdef _WINDOWS _snprintf_s(dba->db_host, sizeof(dba->db_host) - 1, sizeof(dba->db_host) - 1, "%s", host); _snprintf_s(dba->db_user, sizeof(dba->db_user) - 1, sizeof(dba->db_user) - 1, "%s", user); _snprintf_s(dba->db_passwd, sizeof(dba->db_passwd) - 1, sizeof(dba->db_passwd) - 1, "%s", passwd); _snprintf_s(dba->db_name, sizeof(dba->db_name) -1, sizeof(dba->db_name) -1, "%s", db); #else _snprintf(dba->db_host, sizeof(dba->db_host) - 1, "%s", host); _snprintf(dba->db_user, sizeof(dba->db_user) - 1, "%s", user); _snprintf(dba->db_passwd, sizeof(dba->db_passwd) - 1, "%s", passwd); _snprintf(dba->db_name, sizeof(dba->db_name) -1, "%s", db); #endif dba->db_port = (port < 1 ? 3306 : port); //mysql_library_init(0, NULL, NULL); mysql_init(&dba->mysql); if(mysql_real_connect(&dba->mysql, dba->db_host, dba->db_user, dba->db_passwd, dba->db_name, dba->db_port, NULL, 0) == NULL) { #ifdef _WINDOWS _snprintf_s(dba->errmsg, sizeof(dba->errmsg) - 1, sizeof(dba->errmsg) - 1, "Unable to connect to the database,The cause of the error is :%s.", mysql_error(&dba->mysql)); #else _snprintf(dba->errmsg, sizeof(dba->errmsg) - 1, "Unable to connect to the database,The cause of the error is :%s.", mysql_error(&dba->mysql)); #endif mysql_library_end(); return MYSQL_ERROR; } dba->errmsg[0] = 0; return 0; } /*断开数据库连接*/ void dba_disconnect(DBA *dba) { if(dba == NULL) return; if(dba->res != NULL) { dba_freeresult(dba); } mysql_close(&dba->mysql); //mysql_library_end(); dba->errmsg[0] = 0; } /*执行存储过程*/ int dba_execute_procedure(DBA *dba, const char *proc, const char *paramters, ...) { int nlen; unsigned long ret; va_list ap; char sql[MAX_SQLBUF_LEN] = {0}; if(dba == NULL) return 0; if(dba->res != NULL) { dba_freeresult(dba); } #ifdef _WINDOWS _snprintf_s(sql, sizeof(sql) - 1, sizeof(sql) - 1, "call %s(", proc); #else _snprintf(sql, sizeof(sql) - 1, "call %s(", proc); #endif nlen = strlen(sql); va_start(ap, paramters); #ifdef _WINDOWS vsnprintf_s(sql + nlen, MAX_SQLBUF_LEN - nlen - 1, MAX_SQLBUF_LEN - nlen - 1, paramters, ap); #else vsnprintf(sql + nlen, MAX_SQLBUF_LEN - nlen - 1, paramters, ap); #endif va_end(ap); nlen = strlen(sql); #ifdef _WINDOWS _snprintf_s(sql + nlen, sizeof(sql) - 1, sizeof(sql) - 1, ");"); #else _snprintf(sql + nlen, sizeof(sql) - 1, ");"); #endif //printf("sql:%s\n", sql); mysql_query(&dba->mysql, "SET NAMES utf8"); if(mysql_real_query(&dba->mysql, sql, strlen(sql)) != 0) { #ifdef _WINDOWS _snprintf_s(dba->errmsg, sizeof(dba->errmsg) - 1, sizeof(dba->errmsg) - 1, "Execute the %s procdure failure, The cause of the error is:%s.", proc, mysql_error(&dba->mysql)); #else _snprintf(dba->errmsg, sizeof(dba->errmsg) - 1, "Execute the %s procdure failure, The cause of the error is:%s.", proc, mysql_error(&dba->mysql)); #endif return MYSQL_ERROR; } dba->errmsg[0] = 0; ret = (unsigned long)mysql_affected_rows(&dba->mysql); return ret; } /* 执行语句 */ int dba_execute(DBA *dba, const char *paramters, ...) { int ret; va_list ap; char sql[MAX_SQLBUF_LEN] = {0}; if(dba == NULL) return 0; if(dba->res != NULL) { dba_freeresult(dba); } va_start(ap, paramters); #ifdef _WINDOWS vsnprintf_s(sql, MAX_SQLBUF_LEN - 1, MAX_SQLBUF_LEN - 1, paramters, ap); #else vsnprintf(sql, MAX_SQLBUF_LEN - 1, paramters, ap); #endif va_end(ap); //printf("sql:%s\n", sql); mysql_query(&dba->mysql, "SET NAMES utf8"); if(mysql_real_query(&dba->mysql, sql, strlen(sql)) != 0) { return MYSQL_ERROR; } dba->errmsg[0] = 0; ret = (unsigned long)mysql_affected_rows(&dba->mysql); if(ret < 0) { ret = 0; } return ret; } /*获取查询结果集*/ int dba_queryresult(DBA *dba) { if(dba == NULL) return 0; dba->res = mysql_store_result(&dba->mysql); if(dba->res == NULL) { #ifdef _WINDOWS _snprintf_s(dba->errmsg, sizeof(dba->errmsg) - 1, sizeof(dba->errmsg) - 1, "%s", "The query result set is empty."); #else _snprintf(dba->errmsg, sizeof(dba->errmsg) - 1, "%s", "The query result set is empty."); #endif dba->nfieldcount = 0; } else { dba->errmsg[0] = 0; dba->nrowcount = (int)dba->res->row_count; if(dba->nrowcount > 0) { dba->row = mysql_fetch_row(dba->res); } dba->nfieldcount = mysql_num_fields(dba->res); } return (dba->res == NULL ? 0 : dba->nrowcount); } /*结果集的下一行*/ int dba_nextrow(DBA *dba) { if(dba == NULL) return MYSQL_ERROR; if(dba->res == NULL) { #ifdef _WINDOWS _snprintf_s(dba->errmsg, sizeof(dba->errmsg) - 1, sizeof(dba->errmsg) - 1, "%s", "The query result set is empty."); #else _snprintf(dba->errmsg, sizeof(dba->errmsg) - 1, "%s", "The query result set is empty."); #endif return MYSQL_ERROR; } if(!mysql_eof(dba->res)) { #ifdef _WINDOWS _snprintf_s(dba->errmsg, sizeof(dba->errmsg) - 1, sizeof(dba->errmsg) - 1, "%s", "The current row is the last row."); #else _snprintf(dba->errmsg, sizeof(dba->errmsg) - 1, "%s", "The current row is the last row."); #endif return MYSQL_ERROR; } dba->row = mysql_fetch_row(dba->res); if(dba->row == NULL) { #ifdef _WINDOWS _snprintf_s(dba->errmsg, sizeof(dba->errmsg) - 1, sizeof(dba->errmsg) - 1, "%s", "Failed to move to the next row."); #else _snprintf(dba->errmsg, sizeof(dba->errmsg) - 1, "%s", "Failed to move to the next row."); #endif return MYSQL_ERROR; } dba->errmsg[0] = 0; return 0; } /*转到结果集某一行*/ int dba_seekrow(DBA *dba, int nrowindex) { if(dba == NULL) return MYSQL_ERROR; dba->errmsg[0] = 0; if(dba->res != NULL && nrowindex >-1 && nrowindex < dba->nrowcount) { mysql_data_seek(dba->res, nrowindex); return 0; } return MYSQL_ERROR; } /*获取结果集的列数*/ int dba_getfieldcount(DBA *dba) { if(dba == NULL) return 0; dba->errmsg[0] = 0; return dba->nfieldcount; } /*获取列名称*/ char* dba_getfieldname(DBA *dba, int nindex) { if(dba == NULL) return NULL; dba->errmsg[0] = 0; if(dba->res != NULL && nindex > -1 && nindex < dba->nfieldcount) { MYSQL_FIELD *field = mysql_fetch_field_direct(dba->res, nindex); if(field == NULL) { return NULL; } return field->name; } return NULL; } /*获取列值*/ char* dba_getfieldvalue(DBA *dba, int nindex) { if(dba == NULL)