Calling external C dynamic library functions in Oracle

Calling external C dynamic library functions in Oracle
In order to shorten the development time, the project must call the C program that has been developed externally in Oracle.
I found some posts on the Internet and summarized the article based on the actual situation. Hope to help you.
Reference: http://www.cnblogs.com/mathitlin99/archive/2013/09/05/3303717.html

First, compile the external dynamic library libDialPlan. so

 

  
gcc -fPIC -c LibDialPlan.cpp

  
gcc -shared -o libDialPlan.so LibDialPlan.o -lstdc++
 

Modify the Oracle TNS file and listener file.
It is unclear whether the direct copy is available. If you have any questions, pay attention to the equal sign and the spaces on both sides of the brackets.
Tnsnames. ora

 

  
ORADB =

  
(DESCRIPTION =

  
(ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.69.166)(PORT = 1521))

  
(CONNECT_DATA =

  
(SERVER = DEDICATED)

  
(SERVICE_NAME = oradb)

  
) 

  
)

  


  
EXTPROC_CONNECTION_DATA=

  
(DESCRIPTION=

  
(ADDRESS_LIST=

  
(ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1521))

  
)

  
(CONNECT_DATA=

  
(SID = PLSExtProc)

  
(PRESENTATION = RO)

  
)

  
)
 

Listener. ora

 

  
LISTENER =

  
(DESCRIPTION_LIST =

  
(DESCRIPTION =

  
(ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1521))

  
(ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.69.166)(PORT = 1521))

  
)

  
)

  


  
ADR_BASE_LISTENER = /home/oracle/db/app

  


  


  
SID_LIST_LISTENER =

  
(SID_LIST =

  
(SID_DESC =

  
(GLOBAL_DBNAME = oradb)

  
(SID_NAME = oradb)

  
)

  
(SID_DESC=

  
(SID_NAME = PLSExtProc)

  
(ORACLE_HOME = /opt/local/oracle/app/product/11.2.0/dbhome_2)

  
(ENVS = EXTPROC_DLLS=ANY)

  
(PROGRAM = extproc)

  
) 

  
)
 

Restart the listener after modification: lsnrctl stop; lsnrctl start
Check the listening status. The following listening items should appear: PLSExtProc

 

  
[root@localhost admin]# lsnrctl status

  


  
LSNRCTL for Linux: Version 11.2.0.1.0 - Production on 04-AUG-2016 19:33:50

  


  
Copyright (c) 1991, 2009, Oracle. All rights reserved.

  


  
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=IPC)(KEY=EXTPROC1521)))

  
STATUS of the LISTENER

  
------------------------

  
Alias                     LISTENER

  
Version TNSLSNR for Linux: Version 11.2.0.1.0 - Production

  
Start Date                04-AUG-2016 16:23:54

  
Uptime                    0 days 3 hr. 9 min. 55 sec

  
Trace Level               off

  
Security                  ON: Local OS Authentication

  
SNMP                      OFF

  
Listener Parameter File /opt/local/oracle/app/product/11.2.0/dbhome_2/network/admin/listener.ora

  
Listener Log File /opt/local/oracle/app/product/11.2.0/dbhome_2/network/log/listener.log

  
Listening Endpoints Summary...

  
(DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=EXTPROC1521)))

  
(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=192.168.69.166)(PORT=1521)))

  
Services Summary...

  
Service "PLSExtProc" has 1 instance(s).

  
Instance "PLSExtProc", status UNKNOWN, has 1 handler(s) for this service...

  
Service "oradb" has 1 instance(s).

  
Instance "oradb", status UNKNOWN, has 1 handler(s) for this service...

  
The command completed successfully

  
[root@localhost admin]#
 

Create Oraclelibrary object

 

  
create or replace library hytpdtbilldb.Fun_Ext_Proc

  
as '/opt/local/Oracle_install/Oracle_Call_External_C/libDialPlan.so';
  

 

Create a function
1) According to the online article, there is also a parameter.
However, this parameter cannot be compiled after I add it. The removed function does not affect the use of the function.
2) The numbers and strings correspond to the binary_integer and varchar2 types. Originally, input parameters of C require array type, but Oracle does not have a real array and can only be replaced by strings.
3) during my testing, I occasionally need to restart to call the function normally. Pay attention to the usage process.

 

  
create or replace function hytpdtbilldb.Air2Gsi

  
(x binary_integer,y varchar2)

  
return varchar2

  
as

  
language C

  
library hytpdtbilldb.Fun_Ext_Proc 

  
name "Air2Gsi";

  
/