Linux下使用C的API接口登陸和關閉幾種常用的數據庫

 

MySQL下

//dbproc.c

/*************************************************************       
    FileName : dbproc.c   
    FileFunc : C語言接口訪問MySQL      
    Version  : V0.1       
    Author   : Sunrier       
    Date     : 2012-06-14 
    Descp    : Linux下使用C語言訪問MySQL函數        
*************************************************************/   
#include <stdio.h>
#include <stdlib.h>
#include <mysql.h>

static MYSQL s_my_connection;
static int s_iDbconnected = 0;//數據庫連接標誌 連接時爲1,斷開時爲0

int mysql_login(char* pServer,char *pUser,char *pPassword,char *pDataBase)
{
	MYSQL *conn_ptr = NULL;
	MYSQL_RES *res_ptr = NULL;
	MYSQL_ROW sqlrow;
	int iRetCode = 1;
	unsigned int uiTimeOut = 7;

	if( s_iDbconnected )
		return 0;
		
	conn_ptr = mysql_init(&s_my_connection);
	if( !conn_ptr )
	{
		fprintf(stderr,"mysql_init failed ! \n");
		return EXIT_FAILURE;
	}

	iRetCode  = mysql_options(&s_my_connection,MYSQL_OPT_CONNECT_TIMEOUT,(const char *)&uiTimeOut);
	if( iRetCode  )
	{
		fprintf(stderr,"Connection is timeout! \n");
		return EXIT_FAILURE;
	}
	
	conn_ptr = NULL;
	conn_ptr = mysql_real_connect(&s_my_connection,pServer,pUser,pPassword,pDataBase,0,NULL,0);
	if( conn_ptr )
	{
		printf("MySQL Connection success!\n");
		s_iDbconnected = 1;		
	}
	else
	{
		fprintf(stderr,"Connection failed!\n");
		if( mysql_errno(&s_my_connection) )
		{
			fprintf(stderr,"Connection error %d: %s!\n",mysql_errno(&s_my_connection),mysql_error(&s_my_connection));
			return EXIT_FAILURE;
		}
	}
	
	return EXIT_SUCCESS;
}


void mysql_logout( void )
{
	if( s_iDbconnected )
		mysql_close(&s_my_connection);//關閉連接  
	s_iDbconnected = 0 ;
}

 

//demo.c

/*************************************************************       
    FileName : demo.c   
    FileFunc : 測試登陸和關閉MySQL數據庫     
    Version  : V0.1       
    Author   : Sunrier       
    Date     : 2012-06-14  
    Descp    : Linux下使用C語言訪問MySQL函數        
*************************************************************/   
#include <stdio.h>

int main(int argc,char *argv[])
{
	int iRetCode = 0;
	char szServer[20] = "localhost";  
	//char szServer[20] = "192.168.2.8";
  	char szUser[20] = "Sunrier";  
  	char szPassword[20] = "redhat";  
  	char szDatabase[20] = "test";  

	iRetCode = mysql_login(szServer,szUser,szPassword,szDatabase);
	
	if( iRetCode )
	{	
		system("service mysqld start");
		iRetCode = mysql_login(szServer,szUser,szPassword,szDatabase);
	}
		
	printf("iRetCode = %d \n",iRetCode); 
	mysql_logout();
	
	return 0;
}

 

 

//makefile

#makefile
all:demo
demo:demo.c dbproc.c
	@gcc -I/usr/include/mysql $?  -L/usr/lib/mysql -lmysqlclient  -lz -lm -o demo
#	gcc -I/usr/include/mysql demo.c dbproc.c  -L/usr/lib/mysql -lmysqlclient  -lz -lm -o demo
clean:
	@ls | grep -v ^makefile$$ | grep -v [.]c$$ | grep -v [.]h$$ | grep -v [.]sql$$ |xargs rm -rf 
#makefile

 

[root@localhost MYSQL]# ls
dbproc.c  demo.c  makefile
[root@localhost MYSQL]# make
[root@localhost MYSQL]# ./demo
Connection failed!
Connection error 2002: Can't connect to local MySQL server through socket '/var/lib/mysql/mysql.sock' (2)!
啓動 MySQL：                                               [確定]
MySQL Connection success!
iRetCode = 0
[root@localhost MYSQL]#

 

 

 

 

 

DB2下

//dbproc.sqc

/*************************************************************        
    FileName : dbproc.sqc    
    FileFunc : C語言接口訪問本地DB2數據庫      
    Version  : V0.1        
    Author   : Sunrier        
    Date     : 2012-06-15  
    Descp    : Linux下使用C語言訪問DB2函數       
*************************************************************/
//(嵌入SQL語句的關鍵字不區分大小寫)  
#include <stdio.h>
#include <string.h>
#include <sqlca.h>

#define PARAERR                 0x04
#define DATABASEERR             0x08

EXEC SQL include sqlca;

int check_error(char szMessage[])
{
	if( sqlca.sqlcode )
	{
		printf("Check error report : \n");
		printf("Error occured : %s ,sqlcode = [%d] \n",szMessage,sqlca.sqlcode);
		return 1;
  }
  
  return 0;
}

int db2_login(int iArgcFlag,char *pUserName,char *pPassword,char *pDataBase) 
{
	int iRetCode = 1;
	EXEC SQL BEGIN DECLARE SECTION;
	        char szUserName[50];
	        char szPassword[50];
	        char szDataBase[50];
	EXEC SQL END   DECLARE SECTION;
	
	memset(szUserName,0,sizeof(szUserName));
	memset(szPassword,0,sizeof(szPassword));	
	memset(szDataBase,0,sizeof(szDataBase));
	strcpy(szDataBase,pDataBase);

	if( 1==iArgcFlag )
	{
		EXEC SQL CONNECT TO:szDataBase ;
	}
	else
	{
		if( 3==iArgcFlag )
		{
			strcpy(szUserName,pUserName);
		  	strcpy(szPassword,pPassword);
		  	EXEC SQL CONNECT TO:szDataBase USER:szUserName USING:szPassword;
		}	
		else
		{
			printf("Usage : argc found error !\n");
			return PARAERR;
		}	
	}
		
	iRetCode = check_error("CONNECT TO DATABASE");
		
	return iRetCode;
}

void db2_logout( void )
{
	EXEC SQL CONNECT RESET;
	
	check_error("CONNECT RESET");
}

 

 

//demo.c

/*************************************************************        
    FileName : demo.c    
    FileFunc : 測試登陸和關閉DB2數據庫      
    Version  : V0.1        
    Author   : Sunrier        
    Date     : 2012-06-15   
    Descp    : Linux下使用C語言訪問DB2函數         
*************************************************************/     
#include <stdio.h>

int main(int argc,char *argv[])  
{  
    int iRetCode = 0; 
    int iArgcFlag;  
    char szUserName[20] = "Sunrier";    
    char szPassword[20] = "redhat";    
    char szDatabase[20] = "test"; 
 
    iArgcFlag = 3;   
  
    iRetCode = db2_login(iArgcFlag,szUserName,szPassword,szDatabase);  
	      
    printf("iRetCode = %d \n",iRetCode);  
    
    if( iRetCode )
    {  
	printf("DB2 Connection failure !\n");  
	return iRetCode;
    }
    else
    {	
	printf("DB2 Connection success !\n");
    }
	 
    db2_logout();  
      
    return 0;  
}  

 

 

//makefile

all:demo

DB2INCPATH=/home/db2inst1/sqllib/include

DB2LIBPATH=/home/db2inst1/sqllib/lib

demo:demo.c dbproc.sqc
	@db2 connect to test
	@db2 prep dbproc.sqc
	@gcc -ldb2 -L/usr/lib -lm -o demo demo.c dbproc.c 
#	@gcc -L/home/db2inst1/sqllib/lib -ldb2 -L/usr/lib -lm -o demo dbproc.c
clean:
	@ls | grep -v ^makefile$$ | grep -v [.]c$$ | grep -v [.]h$$ | grep -v [.]sqc$$ | grep -v [.]sql$$ |xargs rm -rf   

#@db2start //數據庫的啓動
#@db2stop  //數據庫的停止
#db2 connect to test //連接test數據庫
#db2 prep dbproc.sqc bindfile //prep命令生成.c文件和.bnd文件( 加bindfile選項 )
#db2 bind dbproc.bnd	//bind命令生成PACKET
#gcc -L/home/db2inst1/sqllib/lib -ldb2 -L/usr/lib -lm -o test test.c //生成可執行文件         
#@db2 -r rep.rpt prep dbproc.sqc //把db2 prep dbproc.sqc執行後的信息輸出保存到rep.rpt報告文件中(-r的作用將輸出保存到報告文件) 
#@db2 +o prep dbproc.sqc //不顯示db2 prep dbproc.sqc執行後的信息(+o的作用爲不顯示執行信息)  
## Disconnect from the database.
#@db2 connect reset//db2 disconnect current//斷開數據庫連接,後臺db2bp依然存在
#@db2 terminate  //斷開數據庫連接,幹掉db2bp

 

 

[Sunrier@localhost DB2]$ ls
dbproc.sqc  demo.c  makefile
[Sunrier@localhost DB2]$ make

   Database Connection Information

 Database server        = DB2/LINUX 8.2.3
 SQL authorization ID   = Sunrier
 Local database alias   = TEST

LINE    MESSAGES FOR dbproc.sqc
------  --------------------------------------------------------------------
        SQL0060W  The "C" precompiler is in progress.
        SQL0091W  Precompilation or binding was ended with "0"
                  errors and "0" warnings.
[Sunrier@localhost DB2]$ ls
dbproc.c  dbproc.sqc  demo  demo.c  makefile
[Sunrier@localhost DB2]$ ./demo
iRetCode = 0
DB2 Connection success !
[Sunrier@localhost DB2]$
       

 

 

 

 Informix下

//informixdbproc.ec

/*************************************************************       
    FileName : informixdbproc.ec  
    FileFunc : C語言接口訪問Informix數據庫     
    Version  : V0.1       
    Author   : Sunrier       
    Date     : 2012-07-27 
    Descp    : Linux下使用C語言訪問Informix函數  
*************************************************************/
#include <stdio.h>   
#include <string.h>   
   
EXEC SQL include sqlca;  
  
int check_error(char szMessage[])  
{  
	if( sqlca.sqlcode )  
	{  
		printf("Check error report : \n");  
		printf("Error occured : %s ,sqlcode = [%d] \n",szMessage,sqlca.sqlcode);  
		return 1;  
  	}  
    
	return 0;  
}  
  
int informix_login(char *pDataBase)   
{  
    	int iRetCode = 1;  
    
    	EXEC SQL BEGIN DECLARE SECTION;  
		char szDataBase[30];  
    	EXEC SQL END   DECLARE SECTION;  
  
    	memset(szDataBase,0,sizeof(szDataBase));  
    	strcpy(szDataBase,pDataBase);  
    
    	EXEC SQL CONNECT TO:szDataBase ;  
       
    	iRetCode = check_error("CONNECT TO DATABASE");  
          
    	return iRetCode;  
}  
  
int informix_logout(char *pDataBase)
{
	int iRetCode = 1;
	
	EXEC SQL BEGIN DECLARE SECTION;
		char szDataBase[50+1];
	EXEC SQL END DECLARE SECTION;

	memset(szDataBase,0,sizeof(szDataBase));
	strncpy(szDataBase,pDataBase,50);

	EXEC SQL DISCONNECT :szDataBase;
	
	iRetCode = check_error("DisConnect");
	
	return iRetCode;  
}

int informix_logout_ex( void )  
{  
    	int iRetCode = 1;
		
    	EXEC SQL DISCONNECT CURRENT;  
      
    	iRetCode = check_error("CONNECT RESET");  
    
    	return iRetCode;
}
 

//demo.c

/*************************************************************        
    FileName : demo.c    
    FileFunc : 測試登陸和關閉本地Informix數據庫      
    Version  : V0.1        
    Author   : Sunrier        
    Date     : 2012-07-27   
    Descp    : Linux下使用C語言訪問Informix函數         
*************************************************************/  
#include <stdio.h>

int main(int argc,char *argv[])  
{  
    int iRetCode = 0;    
    char szDatabase[30] = "test"; 

    iRetCode = informix_login(szDatabase);  
	      
    printf("iRetCode = %d \n",iRetCode); 
    
    if( iRetCode )
    {
    	printf("Informix Connection failure !\n");
    }
    else
    {
    	printf("Informix Connection success !\n");
    } 

    /*informix_logout(szDatabase);  */
      
    return 0;  
}   

 

 

 

//makefile

#makefile
OBJS = demo   
all:$(OBJS)  
CFLAGS = -O -w -ansi     
#CFLAGS = -O -Wall -ansi 

CC = gcc $(CFLAGS)

$PATH=$PATH:$HOME/bin:/home/informix/bin:$HOME/sbin:

export PATH
unset USERNAME

INFORMIXDIR=/home/informix
ONCONFIG=onconfig
INFORMIXSERVER=online
LD_LIBRARY_PATH=$LD_LIBRARY_PATH:$INFORMIXDIR/lib:$INFORMIXDIR/lib/esql
export INFORMIXDIR INFORMIXSERVER ONCONFIG  LD_LIBRARY_PATH
DB_LOCALE=zh_CN.gb
CLIENT_LOCALE=zh_CN.gb
SERVER_LOCALE=zh_CN.gb
export DB_LOCALE CLIENT_LOCALE SERVER_LOCALE
export LD_ASSUME_KERNEL=2.4.1
PATH=$INFORMIXDIR/bin:$PATH
export PATH

LD_LIBRARY_PATH=$LD_LIBRARY_PATH:$HOME/src/lib
export LD_LIBRARY_PATH

TERMCAP=$INFORMIXDIR/etc/Termcap
export TERMCAP

ETCPATH=$HOME/etc
export ETCPATH 

#Set system path 
MAINPATH=$(HOME)
SRCPATH=$(MAINPATH)/src
BINPATH=$(MAINPATH)/bin
SYSINCLPATH=$(MAINPATH)/include
SYSLIBPATH=$(MAINPATH)/lib 
APPINCLPATH=$(SRCPATH)/include
APPLIBPATH=$(SRCPATH)/lib

#EC = esql -I$(SYSINCLPATH) -I$(APPINCLPATH) -L$(SYSLIBPATH) -L$(APPLIBPATH)

EC = esql

INFORMIXLINCPATH = -I/home/informix/bin   
INFORMIXLIBPATH = -L/usr/lib/informix  
INFORMIXLIB = -lm

demo:demo.c informixdbproc.ec
	@echo -e "Start compile Informix file ...... "
	@$(EC) -o demo demo.c informixdbproc.ec
#$(EC) -o demo demo.c informixdbproc.ec 不會生成informixdbproc.o文件,只生成informixdbproc.c文件
#或者
#$(EC) -c  informixdbproc.ec 會生成.c和.o文件執行後會生成informixdbproc.c和informixdbproc.o這兩個文件
#@$(EC) -c  informixdbproc.ec 
#$(EC) -o demo demo.c informixdbproc.c 生成可執行文件
#@$(EC) -o demo demo.c informixdbproc.c
#或$(EC) -o demo demo.c informixdbproc.o 生成可執行文件
#@$(EC) -o demo demo.c informixdbproc.o
#	其中$(EC) -o demo demo.c informixdbproc.c和$(EC) -o demo demo.c informixdbproc.o一樣
#或者使用後綴方式
#.SUFFIXES: .ec
#demo:demo.o informixdbproc.o
#        @$(EC) -o $@ $?
#.c.o:
#        @$(CC) -c $<
#.ec.o:
#        @$(EC) -c $<
#        @rm -f $*.c
clean:
	@rm -rf informixdbproc.c 
	@ls | grep -v ^makefile$$ | grep -v [.]c$$ | grep -v [.]h$$ | grep -v [.]sql$$ | grep -v [.]ec$$ | xargs rm -rf
#makefile	

 

 

[Sunrier@localhost Informix]$ ls
demo  demo.c  informixdbproc.ec  makefile
[Sunrier@localhost Informix]$ make
Start compile Informix file ......
[Sunrier@localhost Informix]$ ls
demo  demo.c  informixdbproc.c  informixdbproc.ec  makefile
[Sunrier@localhost Informix]$ ./demo
iRetCode = 0
Informix Connection success !
[Sunrier@localhost Informix]$

 

 

 

 

Oracle下

//oracledbproc.pc

/*************************************************************       
    FileName : oracledbproc.pc  
    FileFunc : C語言接口訪問Oracle數據庫     
    Version  : V0.1       
    Author   : Sunrier       
    Date     : 2012-07-27 
    Descp    : Linux下使用C語言訪問Oracle函數  
*************************************************************/
#include <stdio.h>   
#include <string.h>   
   
EXEC SQL include sqlca;  
  
int check_error(char szMessage[])  
{  
	if( sqlca.sqlcode )  
	{  
		printf("Check error report : \n");  
		printf("Error occured : %s ,sqlcode = [%d] \n",szMessage,sqlca.sqlcode);  
		return 1;  
	}  
    
	return 0;  
}  
  
int oracle_login(char *pUserName,char *pPassword,char *pDataBase)   
{  
    	int iRetCode = 1;  
    
    	EXEC SQL BEGIN DECLARE SECTION;  	    
        	char szUserName[30];  
        	char szPassword[30];  
        	char szDataBase[30];   
    	EXEC SQL END   DECLARE SECTION;  
   	 
    	memset(szUserName,0,sizeof(szUserName));
    	memset(szPassword,0,sizeof(szPassword));
    	memset(szDataBase,0,sizeof(szDataBase)); 
    	 
    	strcpy(szUserName,pUserName);
    	strcpy(szPassword,pPassword);
    	strcpy(szDataBase,pDataBase);   
    
    	EXEC SQL CONNECT :szUserName identified by :szPassword using :szDataBase;  
       
    	iRetCode = check_error("CONNECT TO DATABASE");  
          
    	return iRetCode;  
}  
  
int oracle_logout( void )  
{  
    	int iRetCode = 1;
		
    	EXEC SQL commit work release;
      
    	iRetCode = check_error("DisConnect TO DATABASE");  
    
    	return iRetCode;
}

 

 

//demo.c

/*************************************************************        
    FileName : demo.c    
    FileFunc : 測試登陸和關閉本地Oracle數據庫      
    Version  : V0.1        
    Author   : Sunrier        
    Date     : 2012-07-27   
    Descp    : Linux下使用C語言訪問Oracle函數         
*************************************************************/  
#include <stdio.h>

int main(int argc,char *argv[])  
{  
    int iRetCode = 0;
  
    char szUserName[20] = "Sunrier";
    char szPassword[20] = "redhat";      
    char szDatabase[20] = "test"; 
     
    iRetCode = oracle_login(szUserName,szPassword,szDatabase);  
	      
    printf("iRetCode = %d \n",iRetCode); 
    
    if( iRetCode )
    {
    	printf("Oracle Connection failure !\n");
    	return iRetCode;
    }
    else
    {
    	printf("Oracle Connection success !\n");
    } 

    iRetCode = oracle_logout();  
      
    return iRetCode;  
}   

 

 

//makefile

#makefile   
OBJS = demo     
all:$(OBJS)  

PATH=$PATH:$HOME/bin:$MAINPATH/sbin:$MAINPATH/sql
export PATH
LD_LIBRARY_PATH=$LD_LIBRARY_PATH:$HOME/runlib
export LD_LIBRARY_PATH
export LANG=zh_CN.gb2312

export LANG=zh_cn.gbk
#oracle setting
export NLS_LANG=AMERICAN_AMERICA.ZHS16GBK
TMP=/tmp; export TMP
TMPDIR=$TMP; export TMPDIR

ORACLE_BASE=/home/oracle; export ORACLE_BASE
ORACLE_HOME=$ORACLE_BASE/product/10.2/db_1; export ORACLE_HOME
ORACLE_SID=Sunrier; export ORACLE_SID
ORACLE_TERM=xterm; export ORACLE_TERM
PATH=/usr/sbin:$PATH; export PATH
PATH=$ORACLE_HOME/bin:$PATH; export PATH
LD_LIBRARY_PATH=$LD_LIBRARY_PATH:$ORACLE_HOME/lib:/lib:/usr/lib; export LD_LIBRARY_PATH
CLASSPATH=$ORACLE_HOME/JRE:$ORACLE_HOME/jlib:$ORACLE_HOME/rdbms/jlib; export CLASSPATH

  
CFLAGS = -O -w -ansi       
#CFLAGS = -O -Wall -ansi    
  
CC = gcc $(CFLAGS) 

#Set system path
#運行動態庫路徑
RUNLIBPATH=$(HOME)/runlib
#主路徑
MAINPATH=$(HOME)/Proj
#庫頭文件
SYSINCLPATH=$(MAINPATH)/include

#執行文件
BINPATH=$(HOME)/bin
#源程序路徑
SRCPATH=$(MAINPATH)/src
APPINCLPATH=$(SRCPATH)/include

#PROCFLAGS= \
# include=${ORACLE_HOME}/rdbms/public    \
# include=$(SYSINCLPATH) \
# include=$(APPINCLPATH) \
# parse=full \
# unsafe_null=yes \
# dbms=V8 \
# mode=oracle \
# lines=yes \
# char_map=string 

#proc用來對Oracle源程序.pc進行預編譯,生成單純的C源程序
#PROC= proc $(PROCFLAGS)
PROC= proc

ORALIB=-L$(ORACLE_HOME)/lib  -lclntsh

demo:demo.c oracledbproc.pc
	@echo -e "Start compile Oracle file ......"	
	@$(PROC) PARSE=NONE oracledbproc.pc
	@$(CC) -o $@	demo.c oracledbproc.c $(ORALIB)
#	@$(CC) -o $@	demo.c oracledbproc.c $(ORACLE_HOME)/lib/libclntsh.so

clean:
	@rm -rf oracledbproc.c   
	@ls | grep -v ^makefile$$ | grep -v [.]c$$ | grep -v [.]h$$ | grep -v [.]sql$$ | grep -v [.]pc$$ | xargs rm -rf  
#makefile 

 

 

[Sunrier@localhost Oracle]$ ls
demo.c  makefile  oracledbproc.pc
[Sunrier@localhost Oracle]$ make
Start compile Oracle file ......

Pro*C/C++: Release 10.2.0.5.0 - Production on Fri Jul 27 16:31:30 2012

Copyright (c) 1982, 2007, Oracle.  All rights reserved.

System default option values taken from: /home/oracle/product/10.2/db_1/precomp/admin/pcscfg.cfg
[Sunrier@localhost Oracle]$ ls
demo  demo.c  makefile  oracledbproc.c  oracledbproc.lis  oracledbproc.pc
[Sunrier@localhost Oracle]$ ./demo
iRetCode = 0
Oracle Connection success !
[Sunrier@localhost Oracle]$