From 1d740055daa6e1668f047186d208b0693c6b21ba Mon Sep 17 00:00:00 2001
From: Pieter Wuille <pieter.wuille@gmail.com>
Date: Mon, 20 Feb 2012 20:50:26 +0100
Subject: [PATCH] -loadblock to load from an external blk000?.dat file

---
 src/db.cpp   |  4 ++--
 src/init.cpp | 13 +++++++++++-
 src/main.cpp | 56 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 src/main.h   |  2 ++
 4 files changed, 72 insertions(+), 3 deletions(-)

diff --git a/src/db.cpp b/src/db.cpp
index 39a41894d7f23..670f0a876ce70 100644
--- a/src/db.cpp
+++ b/src/db.cpp
@@ -608,7 +608,7 @@ bool CTxDB::LoadBlockIndex()
     map<pair<unsigned int, unsigned int>, CBlockIndex*> mapBlockPos;
     for (CBlockIndex* pindex = pindexBest; pindex && pindex->pprev; pindex = pindex->pprev)
     {
-        if (pindex->nHeight < nBestHeight-nCheckDepth)
+        if (fRequestShutdown || pindex->nHeight < nBestHeight-nCheckDepth)
             break;
         CBlock block;
         if (!block.ReadFromDisk(pindex))
@@ -710,7 +710,7 @@ bool CTxDB::LoadBlockIndex()
             }
         }
     }
-    if (pindexFork)
+    if (pindexFork && !fRequestShutdown)
     {
         // Reorg back to the fork
         printf("LoadBlockIndex() : *** moving best chain pointer back to block %d\n", pindexFork->nHeight);
diff --git a/src/init.cpp b/src/init.cpp
index 14db9e7f5ea40..a021e849ff461 100644
--- a/src/init.cpp
+++ b/src/init.cpp
@@ -224,7 +224,8 @@ bool AppInit2(int argc, char* argv[])
             "  -keypool=<n>     \t  "   + _("Set key pool size to <n> (default: 100)") + "\n" +
             "  -rescan          \t  "   + _("Rescan the block chain for missing wallet transactions") + "\n" +
             "  -checkblocks=<n> \t\t  " + _("How many blocks to check at startup (default: 2500, 0 = all)") + "\n" +
-            "  -checklevel=<n>  \t\t  " + _("How thorough the block verification is (0-6, default: 1)") + "\n";
+            "  -checklevel=<n>  \t\t  " + _("How thorough the block verification is (0-6, default: 1)") + "\n" +
+            "  -loadblock=<file>\t  "   + _("Imports blocks from external blk000?.dat file") + "\n";
 
         strUsage += string() +
             _("\nSSL options: (see the Bitcoin Wiki for SSL setup instructions)") + "\n" +
@@ -364,6 +365,16 @@ bool AppInit2(int argc, char* argv[])
     }
     printf(" block index %15"PRI64d"ms\n", GetTimeMillis() - nStart);
 
+    if (mapArgs.count("-loadblock"))
+    {
+        BOOST_FOREACH(string strFile, mapMultiArgs["-loadblock"])
+        {
+            FILE *file = fopen(strFile.c_str(), "rb");
+            if (file)
+                LoadExternalBlockFile(file);
+        }
+    }
+
     InitMessage(_("Loading wallet..."));
     printf("Loading wallet...\n");
     nStart = GetTimeMillis();
diff --git a/src/main.cpp b/src/main.cpp
index 78d84d906484d..e2f1af4091ed1 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -2011,6 +2011,62 @@ void PrintBlockTree()
     }
 }
 
+bool LoadExternalBlockFile(FILE* fileIn)
+{
+    int nLoaded = 0;
+    {
+        LOCK(cs_main);
+        try {
+            CAutoFile blkdat(fileIn, SER_DISK, CLIENT_VERSION);
+            unsigned int nPos = 0;
+            while (nPos != -1 && blkdat.good() && !fRequestShutdown)
+            {
+                unsigned char pchData[65536];
+                do {
+                    fseek(blkdat, nPos, SEEK_SET);
+                    int nRead = fread(pchData, 1, sizeof(pchData), blkdat);
+                    if (nRead <= 8)
+                    {
+                        nPos = -1;
+                        break;
+                    }
+                    void* nFind = memchr(pchData, pchMessageStart[0], nRead+1-sizeof(pchMessageStart));
+                    if (nFind)
+                    {
+                        if (memcmp(nFind, pchMessageStart, sizeof(pchMessageStart))==0)
+                        {
+                            nPos += ((unsigned char*)nFind - pchData) + sizeof(pchMessageStart);
+                            break;
+                        }
+                        nPos += ((unsigned char*)nFind - pchData) + 1;
+                    }
+                    else
+                        nPos += sizeof(pchData) - sizeof(pchMessageStart) + 1;
+                } while(!fRequestShutdown);
+                if (nPos == -1)
+                    break;
+                fseek(blkdat, nPos, SEEK_SET);
+                unsigned int nSize;
+                blkdat >> nSize;
+                if (nSize > 0 && nSize <= MAX_BLOCK_SIZE)
+                {
+                    CBlock block;
+                    blkdat >> block;
+                    if (ProcessBlock(NULL,&block))
+                    {
+                        nLoaded++;
+                        nPos += 4 + nSize;
+                    }
+                }
+            }
+        }
+        catch (std::exception &e) 
+        {
+        }
+    }
+    printf("Loaded %i blocks from external file\n", nLoaded);
+    return nLoaded > 0;
+}
 
 
 
diff --git a/src/main.h b/src/main.h
index a814092ac2781..af294b55c73ee 100644
--- a/src/main.h
+++ b/src/main.h
@@ -69,6 +69,7 @@ extern int64 nHPSTimerStart;
 extern int64 nTimeBestReceived;
 extern CCriticalSection cs_setpwalletRegistered;
 extern std::set<CWallet*> setpwalletRegistered;
+extern unsigned char pchMessageStart[4];
 
 // Settings
 extern int64 nTransactionFee;
@@ -91,6 +92,7 @@ bool LoadBlockIndex(bool fAllowNew=true);
 void PrintBlockTree();
 bool ProcessMessages(CNode* pfrom);
 bool SendMessages(CNode* pto, bool fSendTrickle);
+bool LoadExternalBlockFile(FILE* fileIn);
 void GenerateBitcoins(bool fGenerate, CWallet* pwallet);
 CBlock* CreateNewBlock(CReserveKey& reservekey);
 void IncrementExtraNonce(CBlock* pblock, CBlockIndex* pindexPrev, unsigned int& nExtraNonce);