From 7ec552676c66488fe00fb503d02ec4a389a715b7 Mon Sep 17 00:00:00 2001
From: Matt Corallo <matt@bluematt.me>
Date: Tue, 5 Jul 2011 03:06:19 +0200
Subject: [PATCH] Add minversion to wallet.

---
 src/db.cpp     |   15 +++++++++++----
 src/db.h       |    9 ++++++++-
 src/init.cpp   |   12 ++++++++++--
 src/wallet.cpp |    5 +++--
 4 files changed, 32 insertions(+), 9 deletions(-)

diff --git a/src/db.cpp b/src/db.cpp
index f044355..9e13727 100644
--- a/src/db.cpp
+++ b/src/db.cpp
@@ -670,7 +670,7 @@ void CWalletDB::ListAccountCreditDebit(const string& strAccount, list<CAccountin
 }
 
 
-bool CWalletDB::LoadWallet(CWallet* pwallet)
+int CWalletDB::LoadWallet(CWallet* pwallet)
 {
     pwallet->vchDefaultKey.clear();
     int nFileVersion = 0;
@@ -690,7 +690,7 @@ bool CWalletDB::LoadWallet(CWallet* pwallet)
         // Get cursor
         Dbc* pcursor = GetCursor();
         if (!pcursor)
-            return false;
+            return DB_CORRUPT;
 
         loop
         {
@@ -701,7 +701,7 @@ bool CWalletDB::LoadWallet(CWallet* pwallet)
             if (ret == DB_NOTFOUND)
                 break;
             else if (ret != 0)
-                return false;
+                return DB_CORRUPT;
 
             // Unserialize
             // Taking advantage of the fact that pair serialization
@@ -809,6 +809,13 @@ bool CWalletDB::LoadWallet(CWallet* pwallet)
                 if (strKey == "addrProxy")          ssValue >> addrProxy;
                 if (fHaveUPnP && strKey == "fUseUPnP")           ssValue >> fUseUPnP;
             }
+            else if (strType == "minversion")
+            {
+                int nMinVersion = 0;
+                ssValue >> nMinVersion;
+                if (nMinVersion > VERSION)
+                    return DB_TOO_NEW;
+            }
         }
         pcursor->close();
     }
@@ -839,7 +846,7 @@ bool CWalletDB::LoadWallet(CWallet* pwallet)
     }
 
 
-    return true;
+    return DB_LOAD_OK;
 }
 
 void ThreadFlushWalletDB(void* parg)
diff --git a/src/db.h b/src/db.h
index b89b34e..b910111 100644
--- a/src/db.h
+++ b/src/db.h
@@ -342,6 +342,13 @@ public:
 
 
 
+enum DBErrors
+{
+    DB_LOAD_OK,
+    DB_CORRUPT,
+    DB_TOO_NEW
+};
+
 class CWalletDB : public CDB
 {
 public:
@@ -450,7 +457,7 @@ public:
     int64 GetAccountCreditDebit(const std::string& strAccount);
     void ListAccountCreditDebit(const std::string& strAccount, std::list<CAccountingEntry>& acentries);
 
-    bool LoadWallet(CWallet* pwallet);
+    int LoadWallet(CWallet* pwallet);
 };
 
 #endif
diff --git a/src/init.cpp b/src/init.cpp
index 635799c..beaad68 100644
--- a/src/init.cpp
+++ b/src/init.cpp
@@ -387,8 +387,16 @@ bool AppInit2(int argc, char* argv[])
     nStart = GetTimeMillis();
     bool fFirstRun;
     pwalletMain = new CWallet("wallet.dat");
-    if (!pwalletMain->LoadWallet(fFirstRun))
-        strErrors += _("Error loading wallet.dat      \n");
+    int nLoadWalletRet = pwalletMain->LoadWallet(fFirstRun);
+    if (nLoadWalletRet != DB_LOAD_OK)
+    {
+        if (nLoadWalletRet == DB_CORRUPT)
+            strErrors += _("Error loading wallet.dat: Wallet corrupted      \n");
+        else if (nLoadWalletRet == DB_TOO_NEW)
+            strErrors += _("Error loading wallet.dat: Wallet requires newer version of Bitcoin      \n");
+        else
+            strErrors += _("Error loading wallet.dat      \n");
+    }
     printf(" wallet      %15"PRI64d"ms\n", GetTimeMillis() - nStart);
 
     RegisterWallet(pwalletMain);
diff --git a/src/wallet.cpp b/src/wallet.cpp
index e54bbb3..ba9221f 100644
--- a/src/wallet.cpp
+++ b/src/wallet.cpp
@@ -958,8 +958,9 @@ bool CWallet::LoadWallet(bool& fFirstRunRet)
     if (!fFileBacked)
         return false;
     fFirstRunRet = false;
-    if (!CWalletDB(strWalletFile,"cr+").LoadWallet(this))
-        return false;
+    int nLoadWalletRet = CWalletDB(strWalletFile,"cr+").LoadWallet(this);
+    if (nLoadWalletRet != DB_LOAD_OK)
+        return nLoadWalletRet;
     fFirstRunRet = vchDefaultKey.empty();
 
     if (!mapKeys.count(vchDefaultKey))
-- 
1.7.1