Merge #10919: Fix more init bugs.

e7539f8 Fix some broken init-time prints/constants (Matt Corallo)
13ab353 Check for empty coinsview instead of just-reset coinsview in init (Matt Corallo)
fce3f4f Fix resume-of-reindex-after-restart (Matt Corallo)
efac91e Always wait for threadGroup to exit in bitcoind shutdown (Matt Corallo)

Pull request description:

  This is a follow-on to #10758 to help move 10758 along. The first fixes a regression in master that was partially fixed in 10758, the second I'm not sure if its a regression or not, but its clearly a bug that should be fixed.

Tree-SHA512: aca7b97a97dca66e1a218a33cc6f4aa002292ff1bb0af64e35b81fbaa91b9504f2605375808b43e93a63fc73634ad079b30ef6c9f4ba338d3b5f72d816dfeaff

4 files changed, 14 insertions, 13 deletions

diff --git a/src/bitcoind.cpp b/src/bitcoind.cpp
index f3844e9d47..ff61b9065b 100644
--- a/src/bitcoind.cpp
+++ b/src/bitcoind.cpp
@@ -176,9 +176,7 @@ bool AppInit(int argc, char* argv[])
     if (!fRet)
     {
         Interrupt(threadGroup);
-        // threadGroup.join_all(); was left out intentionally here, because we didn't re-test all of
-        // the startup-failure cases to make sure they don't result in a hang due to some
-        // thread-blocking-waiting-for-another-thread-during-startup case
+        threadGroup.join_all();
     } else {
         WaitForShutdown(&threadGroup);
     }
diff --git a/src/init.cpp b/src/init.cpp
index 0ee828ce92..ca62d3e7cc 100644
--- a/src/init.cpp
+++ b/src/init.cpp
@@ -1400,9 +1400,9 @@ bool AppInitMain(boost::thread_group& threadGroup, CScheduler& scheduler)
                 delete pcoinscatcher;
                 delete pblocktree;
 
-                pblocktree = new CBlockTreeDB(nBlockTreeDBCache, false, fReindex);
+                pblocktree = new CBlockTreeDB(nBlockTreeDBCache, false, fReset);
 
-                if (fReindex) {
+                if (fReset) {
                     pblocktree->WriteReindexing(true);
                     //If we're reindexing in prune mode, wipe away unusable block files and all undo data files
                     if (fPruneMode)
@@ -1414,6 +1414,8 @@ bool AppInitMain(boost::thread_group& threadGroup, CScheduler& scheduler)
                 // LoadBlockIndex will load fTxIndex from the db, or set it if
                 // we're reindexing. It will also load fHavePruned if we've
                 // ever removed a block file from disk.
+                // Note that it also sets fReindex based on the disk flag!
+                // From here on out fReindex and fReset mean something different!
                 if (!LoadBlockIndex(chainparams)) {
                     strLoadError = _("Error loading block database");
                     break;
@@ -1438,8 +1440,9 @@ bool AppInitMain(boost::thread_group& threadGroup, CScheduler& scheduler)
                 }
 
                 // At this point blocktree args are consistent with what's on disk.
-                // If we're not mid-reindex (based on disk + args), add a genesis block on disk.
-                // This is called again in ThreadImport in the reindex completes.
+                // If we're not mid-reindex (based on disk + args), add a genesis block on disk
+                // (otherwise we use the one already on disk).
+                // This is called again in ThreadImport after the reindex completes.
                 if (!fReindex && !LoadGenesisBlock(chainparams)) {
                     strLoadError = _("Error initializing block database");
                     break;
@@ -1448,7 +1451,7 @@ bool AppInitMain(boost::thread_group& threadGroup, CScheduler& scheduler)
                 // At this point we're either in reindex or we've loaded a useful
                 // block tree into mapBlockIndex!
 
-                pcoinsdbview = new CCoinsViewDB(nCoinDBCache, false, fReindex || fReindexChainState);
+                pcoinsdbview = new CCoinsViewDB(nCoinDBCache, false, fReset || fReindexChainState);
                 pcoinscatcher = new CCoinsViewErrorCatcher(pcoinsdbview);
 
                 // If necessary, upgrade from older database format.
@@ -1467,7 +1470,8 @@ bool AppInitMain(boost::thread_group& threadGroup, CScheduler& scheduler)
                 // The on-disk coinsdb is now in a good state, create the cache
                 pcoinsTip = new CCoinsViewCache(pcoinscatcher);
 
-                if (!fReindex && !fReindexChainState) {
+                bool is_coinsview_empty = fReset || fReindexChainState || pcoinsTip->GetBestBlock().IsNull();
+                if (!is_coinsview_empty) {
                     // LoadChainTip sets chainActive based on pcoinsTip's best block
                     if (!LoadChainTip(chainparams)) {
                         strLoadError = _("Error initializing block database");
@@ -1476,7 +1480,7 @@ bool AppInitMain(boost::thread_group& threadGroup, CScheduler& scheduler)
                     assert(chainActive.Tip() != NULL);
                 }
 
-                if (!fReindex) {
+                if (!fReset) {
                     // Note that RewindBlockIndex MUST run even if we're about to -reindex-chainstate.
                     // It both disconnects blocks based on chainActive, and drops block data in
                     // mapBlockIndex based on lack of available witness data.
@@ -1487,7 +1491,7 @@ bool AppInitMain(boost::thread_group& threadGroup, CScheduler& scheduler)
                     }
                 }
 
-                if (!fReindex && !fReindexChainState) {
+                if (!is_coinsview_empty) {
                     uiInterface.InitMessage(_("Verifying blocks..."));
                     if (fHavePruned && GetArg("-checkblocks", DEFAULT_CHECKBLOCKS) > MIN_BLOCKS_TO_KEEP) {
                         LogPrintf("Prune: pruned datadir may not have more than %d blocks; only checking available blocks",
diff --git a/src/test/test_bitcoin.cpp b/src/test/test_bitcoin.cpp
index 545e56983c..e2e0a9668f 100644
--- a/src/test/test_bitcoin.cpp
+++ b/src/test/test_bitcoin.cpp
@@ -75,7 +75,7 @@ TestingSetup::TestingSetup(const std::string& chainName) : BasicTestingSetup(cha
         pcoinsdbview = new CCoinsViewDB(1 << 23, true);
         pcoinsTip = new CCoinsViewCache(pcoinsdbview);
         if (!LoadGenesisBlock(chainparams)) {
-            throw std::runtime_error("InitBlockIndex failed.");
+            throw std::runtime_error("LoadGenesisBlock failed.");
         }
         {
             CValidationState state;
diff --git a/src/validation.cpp b/src/validation.cpp
index babf6f1522..405ff356f5 100644
--- a/src/validation.cpp
+++ b/src/validation.cpp
@@ -3916,7 +3916,6 @@ bool LoadGenesisBlock(const CChainParams& chainparams)
     if (mapBlockIndex.count(chainparams.GenesisBlock().GetHash()))
         return true;
 
-    // Only add the genesis block if not reindexing (in which case we reuse the one already on disk)
     try {
         CBlock &block = const_cast<CBlock&>(chainparams.GenesisBlock());
         // Start new block file