From 92f2d9b4af1fcba453126ccef37eae337e76ccd1 Mon Sep 17 00:00:00 2001
From: kiritow <1362050620@qq.com>
Date: Sun, 16 Apr 2017 17:32:39 +0800
Subject: [PATCH] Change pointers to smart pointer (shared_ptr)

---
 sqlite_wrapper.cpp | 36 +++++++++++++++++++++++-------------
 sqlite_wrapper.h   | 20 +++++++++++++-------
 2 files changed, 36 insertions(+), 20 deletions(-)

diff --git a/sqlite_wrapper.cpp b/sqlite_wrapper.cpp
index 37cf6b8..e8822ad 100644
--- a/sqlite_wrapper.cpp
+++ b/sqlite_wrapper.cpp
@@ -2,47 +2,57 @@
 #include <cstring>
 #include <cstdio>
 
-SQLStatement::SQLStatement()
+// private
+void SQLStatement::_set(sqlite3_stmt* p)
 {
-    _st=nullptr;
+    _st.reset(p,sqlite3_finalize);
 }
 
-SQLStatement::~SQLStatement()
+// private
+sqlite3_stmt* SQLStatement::_get() const
 {
-    sqlite3_finalize(_st);
+    return _st.get();
 }
 
 void SQLStatement::_setStmt(sqlite3_stmt* p)
 {
-    _st=p;
+    _set(p);
 }
 
 sqlite3_stmt* SQLStatement::_getStmt() const
 {
-    return _st;
+    return _get();
+}
+
+bool SQLStatement::isReady() const
+{
+    return _get()!=nullptr;
 }
 
 
-SQLDB::SQLDB()
+void SQLDB::_set(sqlite3* p)
 {
-    _db=nullptr;
+    _db.reset(p,sqlite3_close);
 }
 
-SQLDB::~SQLDB()
+sqlite3* SQLDB::_get()
 {
-    sqlite3_close(_db);
+    return _db.get();
 }
 
 int SQLDB::open(const std::string& filename)
 {
-    return sqlite3_open(filename.c_str(),&_db);
+    sqlite3* _temp=nullptr;
+    int ret=sqlite3_open(filename.c_str(),&_temp);
+    _set(_temp);
+    return ret;
 }
 
 SQLStatement SQLDB::prepare(const std::string& SQLCommand)
 {
     SQLStatement stmt;
     sqlite3_stmt* pstmt=nullptr;
-    int ret=sqlite3_prepare(_db,SQLCommand.c_str(),SQLCommand.size(),&pstmt,NULL);
+    int ret=sqlite3_prepare(_get(),SQLCommand.c_str(),SQLCommand.size(),&pstmt,NULL);
     if(ret<0) return stmt;
     stmt._setStmt(pstmt);
     return stmt;
@@ -56,7 +66,7 @@ int SQLDB::step(const SQLStatement& Statement)
 int SQLDB::exec(const std::string& SQLCommand,SQLCallback callback,void* param)
 {
     char* errmsg=nullptr;
-    int ret=sqlite3_exec(_db,SQLCommand.c_str(),callback,param,&errmsg);
+    int ret=sqlite3_exec(_get(),SQLCommand.c_str(),callback,param,&errmsg);
     printf("ErrMsg: %s\n",errmsg);
     return ret;
 }
diff --git a/sqlite_wrapper.h b/sqlite_wrapper.h
index 65bbdc9..9364192 100644
--- a/sqlite_wrapper.h
+++ b/sqlite_wrapper.h
@@ -1,18 +1,21 @@
 #pragma once
 #include "sqlite/sqlite3.h"
 #include <string>
+#include <memory>
 
 class SQLStatement
 {
 public:
-    bool isReady();
-    SQLStatement();
-    ~SQLStatement();
+    bool isReady() const;
+    SQLStatement()=default;
+    ~SQLStatement()=default;
 
     void _setStmt(sqlite3_stmt*);
     sqlite3_stmt* _getStmt() const;
 private:
-    sqlite3_stmt* _st;
+    sqlite3_stmt* _get() const;
+    void _set(sqlite3_stmt*);
+    std::shared_ptr<sqlite3_stmt> _st;
 };
 
 
@@ -21,15 +24,18 @@ using SQLCallback = int (*)(void* ExParam,int colNum,char** colVal,char** colNam
 class SQLDB
 {
 public:
-    SQLDB();
-    ~SQLDB();
+    SQLDB()=default;
+    ~SQLDB()=default;
+
     bool isOpened();
     int open(const std::string& filename);
     SQLStatement prepare(const std::string& SQLCommand);
     int step(const SQLStatement& Statement);
     int exec(const std::string& SQLCommand,SQLCallback callback,void* param);
 private:
-    sqlite3* _db;
+    sqlite3* _get();
+    void _set(sqlite3*);
+    std::shared_ptr<sqlite3> _db;
 };