From b3d23ab2337c8697c7984ada47bbfaa1e97964bb Mon Sep 17 00:00:00 2001
From: Isaac Connor <iconnor@tesla.com>
Date: Thu, 1 Mar 2018 19:20:29 -0800
Subject: [PATCH] merge zma_to_thread version of db functions, which include a
 mutex lock

---
 src/zm_db.cpp | 25 +++++++++++++++++--------
 src/zm_db.h   | 35 ++++++++++++++---------------------
 2 files changed, 31 insertions(+), 29 deletions(-)

diff --git a/src/zm_db.cpp b/src/zm_db.cpp
index fb716349e..fc5ee5fe0 100644
--- a/src/zm_db.cpp
+++ b/src/zm_db.cpp
@@ -23,29 +23,35 @@
 #include "zm.h"
 #include "zm_db.h"
 
+// From what I read, we need one of these per thread
 MYSQL dbconn;
+Mutex db_mutex;
 
-int zmDbConnected = false;
+bool zmDbConnected = false;
 
-void zmDbConnect() {
+bool zmDbConnect() {
   // For some reason having these lines causes memory corruption and crashing on newer debian/ubuntu
   //if ( zmDbConnected ) 
     //return;
 
   if ( !mysql_init( &dbconn ) ) {
     Error( "Can't initialise database connection: %s", mysql_error( &dbconn ) );
-    exit( mysql_errno( &dbconn ) );
+    return false;
   }
   my_bool reconnect = 1;
   if ( mysql_options( &dbconn, MYSQL_OPT_RECONNECT, &reconnect ) )
-    Fatal( "Can't set database auto reconnect option: %s", mysql_error( &dbconn ) );
+    Error( "Can't set database auto reconnect option: %s", mysql_error( &dbconn) );
   if ( !staticConfig.DB_SSL_CA_CERT.empty() )
-    mysql_ssl_set( &dbconn, staticConfig.DB_SSL_CLIENT_KEY.c_str(), staticConfig.DB_SSL_CLIENT_CERT.c_str(), staticConfig.DB_SSL_CA_CERT.c_str(), NULL, NULL );
+    mysql_ssl_set( &dbconn,
+        staticConfig.DB_SSL_CLIENT_KEY.c_str(),
+        staticConfig.DB_SSL_CLIENT_CERT.c_str(),
+        staticConfig.DB_SSL_CA_CERT.c_str(),
+        NULL, NULL );
   std::string::size_type colonIndex = staticConfig.DB_HOST.find( ":" );
   if ( colonIndex == std::string::npos ) {
     if ( !mysql_real_connect( &dbconn, staticConfig.DB_HOST.c_str(), staticConfig.DB_USER.c_str(), staticConfig.DB_PASS.c_str(), NULL, 0, NULL, 0 ) ) {
       Error( "Can't connect to server: %s", mysql_error( &dbconn ) );
-      exit( mysql_errno( &dbconn ) );
+      return false;
     }
   } else {
     std::string dbHost = staticConfig.DB_HOST.substr( 0, colonIndex );
@@ -53,12 +59,12 @@ void zmDbConnect() {
     if ( dbPortOrSocket[0] == '/' ) {
       if ( !mysql_real_connect( &dbconn, NULL, staticConfig.DB_USER.c_str(), staticConfig.DB_PASS.c_str(), NULL, 0, dbPortOrSocket.c_str(), 0 ) ) {
         Error( "Can't connect to server: %s", mysql_error( &dbconn ) );
-        exit( mysql_errno( &dbconn ) );
+        return false;
       }
     } else {
       if ( !mysql_real_connect( &dbconn, dbHost.c_str(), staticConfig.DB_USER.c_str(), staticConfig.DB_PASS.c_str(), NULL, atoi(dbPortOrSocket.c_str()), NULL, 0 ) ) {
         Error( "Can't connect to server: %s", mysql_error( &dbconn ) );
-        exit( mysql_errno( &dbconn ) );
+        return false;
       }
     }
   }
@@ -67,6 +73,7 @@ void zmDbConnect() {
     exit( mysql_errno( &dbconn ) );
   }
   zmDbConnected = true;
+  return zmDbConnected;
 }
 
 void zmDbClose() {
@@ -84,6 +91,7 @@ MYSQL_RES * zmDbFetch( const char * query ) {
     Error( "Not connected." );
     return NULL;
   }
+  db_mutex.lock();
 
   if ( mysql_query( &dbconn, query ) ) {
     Error( "Can't run query: %s", mysql_error( &dbconn ) );
@@ -95,6 +103,7 @@ MYSQL_RES * zmDbFetch( const char * query ) {
     Error( "Can't use query result: %s for query %s", mysql_error( &dbconn ), query );
     return NULL;
   }
+  db_mutex.unlock();
   return result;
 } // end MYSQL_RES * zmDbFetch( const char * query );
 
diff --git a/src/zm_db.h b/src/zm_db.h
index f9b158be8..267995e70 100644
--- a/src/zm_db.h
+++ b/src/zm_db.h
@@ -21,37 +21,30 @@
 #define ZM_DB_H
 
 #include <mysql/mysql.h>
+#include "zm_thread.h"
 
 class zmDbRow {
-    private:
-        MYSQL_RES *result_set;
-        MYSQL_ROW row;
-    public:
-        zmDbRow() { result_set = NULL; row = NULL; };
-        MYSQL_RES *fetch( const char *query );
-        zmDbRow( MYSQL_RES *, MYSQL_ROW *row );
-        ~zmDbRow();
+  private:
+    MYSQL_RES *result_set;
+    MYSQL_ROW row;
+  public:
+    zmDbRow() { result_set = NULL; row = NULL; };
+    MYSQL_RES *fetch( const char *query );
+    zmDbRow( MYSQL_RES *, MYSQL_ROW *row );
+    ~zmDbRow();
 
-        char *operator[](unsigned int index) const {
-            return row[index];
-        }
+    char *operator[](unsigned int index) const {
+      return row[index];
+    }
 };
 
-#ifdef __cplusplus 
-extern "C" {
-#endif 
 extern MYSQL dbconn;
+extern Mutex db_mutex;
 
-extern int zmDbConnected;
-
-void zmDbConnect();
+bool zmDbConnect();
 void zmDbClose();
 
 MYSQL_RES * zmDbFetch( const char *query );
 zmDbRow *zmDbFetchOne( const char *query );
 
-#ifdef __cplusplus 
-} /* extern "C" */
-#endif 
-
 #endif // ZM_DB_H