From fa8685597e7302fc136f21b6dd3a4b187fa8e251 Mon Sep 17 00:00:00 2001
From: MarcoFalke <*~=`'#}+{/-|&$^_@721217.xyz>
Date: Tue, 1 Aug 2023 11:01:48 +0200
Subject: [PATCH] index: Drop legacy -txindex check

---
 src/init.cpp                                  |  5 ---
 src/txdb.cpp                                  | 33 +++++++------------
 src/txdb.h                                    |  3 --
 .../feature_txindex_compatibility.py          | 11 -------
 4 files changed, 12 insertions(+), 40 deletions(-)

diff --git a/src/init.cpp b/src/init.cpp
index c11f100139d..3cf6471d9f8 100644
--- a/src/init.cpp
+++ b/src/init.cpp
@@ -1550,11 +1550,6 @@ bool AppInitMain(NodeContext& node, interfaces::BlockAndHeaderTipInfo* tip_info)
     // ********************************************************* Step 8: start indexers
 
     if (args.GetBoolArg("-txindex", DEFAULT_TXINDEX)) {
-        auto result{WITH_LOCK(cs_main, return CheckLegacyTxindex(*Assert(chainman.m_blockman.m_block_tree_db)))};
-        if (!result) {
-            return InitError(util::ErrorString(result));
-        }
-
         g_txindex = std::make_unique<TxIndex>(interfaces::MakeChain(node), cache_sizes.tx_index, false, fReindex);
         node.indexes.emplace_back(g_txindex.get());
     }
diff --git a/src/txdb.cpp b/src/txdb.cpp
index e5b5e0b8a12..670aaab6063 100644
--- a/src/txdb.cpp
+++ b/src/txdb.cpp
@@ -6,15 +6,23 @@
 #include <txdb.h>
 
 #include <chain.h>
+#include <coins.h>
+#include <dbwrapper.h>
+#include <kernel/cs_main.h>
 #include <logging.h>
 #include <pow.h>
+#include <primitives/transaction.h>
 #include <random.h>
+#include <serialize.h>
+#include <sync.h>
 #include <uint256.h>
 #include <util/signalinterrupt.h>
 #include <util/translation.h>
 #include <util/vector.h>
 
-#include <stdint.h>
+#include <cassert>
+#include <cstdlib>
+#include <iterator>
 
 static constexpr uint8_t DB_COIN{'C'};
 static constexpr uint8_t DB_BLOCK_FILES{'f'};
@@ -28,26 +36,9 @@ static constexpr uint8_t DB_LAST_BLOCK{'l'};
 
 // Keys used in previous version that might still be found in the DB:
 static constexpr uint8_t DB_COINS{'c'};
-static constexpr uint8_t DB_TXINDEX_BLOCK{'T'};
-//               uint8_t DB_TXINDEX{'t'}
-
-util::Result<void> CheckLegacyTxindex(CBlockTreeDB& block_tree_db)
-{
-    CBlockLocator ignored{};
-    if (block_tree_db.Read(DB_TXINDEX_BLOCK, ignored)) {
-        return util::Error{_("The -txindex upgrade started by a previous version cannot be completed. Restart with the previous version or run a full -reindex.")};
-    }
-    bool txindex_legacy_flag{false};
-    block_tree_db.ReadFlag("txindex", txindex_legacy_flag);
-    if (txindex_legacy_flag) {
-        // Disable legacy txindex and warn once about occupied disk space
-        if (!block_tree_db.WriteFlag("txindex", false)) {
-            return util::Error{Untranslated("Failed to write block index db flag 'txindex'='0'")};
-        }
-        return util::Error{_("The block index db contains a legacy 'txindex'. To clear the occupied disk space, run a full -reindex, otherwise ignore this error. This error message will not be displayed again.")};
-    }
-    return {};
-}
+// CBlockTreeDB::DB_TXINDEX_BLOCK{'T'};
+// CBlockTreeDB::DB_TXINDEX{'t'}
+// CBlockTreeDB::ReadFlag("txindex")
 
 bool CCoinsViewDB::NeedsUpgrade()
 {
diff --git a/src/txdb.h b/src/txdb.h
index 6405437be93..d773f01b505 100644
--- a/src/txdb.h
+++ b/src/txdb.h
@@ -11,7 +11,6 @@
 #include <kernel/cs_main.h>
 #include <sync.h>
 #include <util/fs.h>
-#include <util/result.h>
 
 #include <cstddef>
 #include <cstdint>
@@ -105,6 +104,4 @@ public:
         EXCLUSIVE_LOCKS_REQUIRED(::cs_main);
 };
 
-[[nodiscard]] util::Result<void> CheckLegacyTxindex(CBlockTreeDB& block_tree_db);
-
 #endif // BITCOIN_TXDB_H
diff --git a/test/functional/feature_txindex_compatibility.py b/test/functional/feature_txindex_compatibility.py
index 572e12df138..939271b3851 100755
--- a/test/functional/feature_txindex_compatibility.py
+++ b/test/functional/feature_txindex_compatibility.py
@@ -7,7 +7,6 @@
 Previous releases are required by this test, see test/README.md.
 """
 
-import os
 import shutil
 
 from test_framework.test_framework import BitcoinTestFramework
@@ -55,10 +54,6 @@ class TxindexCompatibilityTest(BitcoinTestFramework):
         drop_index_chain_dir = self.nodes[1].chain_path
         shutil.rmtree(drop_index_chain_dir)
         shutil.copytree(legacy_chain_dir, drop_index_chain_dir)
-        self.nodes[1].assert_start_raises_init_error(
-            extra_args=["-txindex"],
-            expected_msg="Error: The block index db contains a legacy 'txindex'. To clear the occupied disk space, run a full -reindex, otherwise ignore this error. This error message will not be displayed again.",
-        )
         # Build txindex from scratch and check there is no error this time
         self.start_node(1, extra_args=["-txindex"])
         self.wait_until(lambda: self.nodes[1].getindexinfo()["txindex"]["synced"] == True)
@@ -66,12 +61,6 @@ class TxindexCompatibilityTest(BitcoinTestFramework):
 
         self.stop_nodes()
 
-        self.log.info("Check migrated txindex cannot be read by legacy node")
-        err_msg = f": You need to rebuild the database using -reindex to change -txindex.{os.linesep}Please restart with -reindex or -reindex-chainstate to recover."
-        shutil.rmtree(legacy_chain_dir)
-        shutil.copytree(drop_index_chain_dir, legacy_chain_dir)
-        self.nodes[0].assert_start_raises_init_error(extra_args=["-txindex"], expected_msg=err_msg)
-
 
 if __name__ == "__main__":
     TxindexCompatibilityTest().main()