From 43d542db69e9f67cdbefb37fb753581ece3080a9 Mon Sep 17 00:00:00 2001
From: paulc <paulc@acf43c95-373e-0410-b603-e72c3f656dc1>
Date: Mon, 26 Jan 2009 23:27:33 +0000
Subject: [PATCH] Fixed the MySQL library and thread initialization. Deal with
 failed connection attempts, try to reconnect on initialize.

git-svn-id: http://yate.null.ro/svn/yate/trunk@2455 acf43c95-373e-0410-b603-e72c3f656dc1
---
 modules/server/mysqldb.cpp | 77 ++++++++++++++++++++++++++++----------
 1 file changed, 57 insertions(+), 20 deletions(-)

diff --git a/modules/server/mysqldb.cpp b/modules/server/mysqldb.cpp
index 51005385..5252618f 100644
--- a/modules/server/mysqldb.cpp
+++ b/modules/server/mysqldb.cpp
@@ -43,21 +43,25 @@
 using namespace TelEngine;
 namespace { // anonymous
 
+class DbThread;
+
 static ObjList s_conns;
 Mutex s_conmutex;
 
 class DbConn : public GenObject
 {
+    friend class DbThread;
 public:
     DbConn(const NamedList* sect);
     ~DbConn();
     virtual const String& toString() const
 	{ return m_name; }
 
-    bool ok();
     int queryDb(const char* query, Message* dest = 0);
     bool initDb();
     void dropDb();
+    inline bool ok() const
+	{ return 0 != m_thread; }
     inline Mutex& mutex()
 	{ return m_dbmutex; }
     void runQueries();
@@ -71,7 +75,8 @@ private:
     int queryDbInternal();
     String m_name;
     unsigned int m_timeout;
-    MYSQL *m_conn;
+    MYSQL* m_conn;
+    DbThread* m_thread;
     String m_host;
     String m_user;
     String m_pass;
@@ -119,9 +124,12 @@ private:
 };
 
 static MyModule module;
+static Mutex s_libMutex(false);
+static int s_libCounter = 0;
 
 DbConn::DbConn(const NamedList* sect)
-    : m_dbmutex(true), m_name(*sect), m_conn(0), m_msg(0), m_go(false)
+    : m_dbmutex(true), m_name(*sect),
+      m_conn(0), m_thread(0), m_msg(0), m_go(false)
 {
     int tout = sect->getIntValue("timeout",10000);
     // round to seconds
@@ -268,8 +276,10 @@ void DbConn::runQueries()
 	    m_msg = 0;
 	    m_query.clear();
 	    m_go = false;
+	    Thread::yield(true);
 	}
-	Thread::yield(true);
+	else
+	    Thread::msleep(10,true);
     }
 }
 
@@ -290,7 +300,7 @@ int DbConn::queryDb(const char* query, Message* dest)
     m_query = query;
     m_go = true;
     while (m_go)
-	Thread::yield();
+	Thread::msleep(1);
     if (m_res < 0)
 	failure(dest);
     return m_res;
@@ -299,16 +309,33 @@ int DbConn::queryDb(const char* query, Message* dest)
 
 void DbThread::run()
 {
-    mysql_library_init(0,0,0);
-    if (m_conn->initDb())
+    s_libMutex.lock();
+    if (0 == s_libCounter++) {
+	DDebug(&module,DebugAll,"Initializing the MySQL library");
+	mysql_library_init(0,0,0);
+    }
+    s_libMutex.unlock();
+    mysql_thread_init();
+    if (m_conn->initDb()) {
+	m_conn->m_thread = this;
 	m_conn->runQueries();
+    }
 }
 
 void DbThread::cleanup()
 {
-    m_conn->dropDb();
-    mysql_library_end();
+    Debug(&module,DebugNote,"Cleaning up connection %p",m_conn);
+    if (m_conn) {
+	m_conn->m_thread = 0;
+	m_conn->dropDb();
+    }
     mysql_thread_end();
+    s_libMutex.lock();
+    if (0 == --s_libCounter) {
+	DDebug(&module,DebugAll,"Deinitializing the MySQL library");
+	mysql_library_end();
+    }
+    s_libMutex.unlock();
 }
 
 
@@ -320,6 +347,7 @@ static DbConn* findDb(String& account)
     return l ? static_cast<DbConn *>(l->get()): 0;
 }
 
+
 bool MyHandler::received(Message& msg)
 {
     String tmp(msg.getValue("account"));
@@ -327,7 +355,7 @@ bool MyHandler::received(Message& msg)
 	return false;
     Lock lock(s_conmutex);
     DbConn* db = findDb(tmp);
-    if (!db)
+    if (!(db && db->ok()))
 	return false;
     Lock lo(db->mutex());
     lock.drop();
@@ -337,8 +365,9 @@ bool MyHandler::received(Message& msg)
     return true;
 }
 
+
 MyModule::MyModule()
-    : Module ("mysqldb","database",true),m_init(false)
+    : Module ("mysqldb","database",true),m_init(true)
 {
     Output("Loaded module MySQL based on %s",mysql_get_client_info());
 }
@@ -356,25 +385,33 @@ void MyModule::statusParams(String& str)
 
 void MyModule::initialize()
 {
-    Module::initialize();
-    if (m_init)
-	return;
-    m_init = true;
     Output("Initializing module MySQL");
+    Module::initialize();
     Configuration cfg(Engine::configFile("mysqldb"));
-    Engine::install(new MyHandler(cfg.getIntValue("general","priority",100)));
-    unsigned int i;
-    for (i = 0; i < cfg.sections(); i++) {
+    if (m_init)
+	Engine::install(new MyHandler(cfg.getIntValue("general","priority",100)));
+    m_init = false;
+    for (unsigned int i = 0; i < cfg.sections(); i++) {
 	NamedList* sec = cfg.getSection(i);
 	if (!sec || (*sec == "general"))
 	    continue;
-	DbConn* conn = new DbConn(sec);
+	DbConn* conn = findDb(*sec);
+	if (conn) {
+	    if (!conn->ok()) {
+		Debug(this,DebugNote,"Reinitializing connection '%s'",conn->toString().c_str());
+		DbThread* thr = new DbThread(conn);
+		if (!thr->startup())
+		    delete thr;
+	    }
+	    continue;
+	}
+	conn = new DbConn(sec);
 	DbThread* thr = new DbThread(conn);
 	if (thr->startup())
 	    s_conns.insert(conn);
 	else {
 	    delete thr;
-	    conn->destruct();
+	    TelEngine::destruct(conn);
 	}
     }
 }