Merge 24558c2cf18210f46d6e2fadf0c5c5912f4b8e10 into 5f4422d68dc3530c353af1f87499de1c864b60ad

3301d2cbe8c3b76c97285d75fa59637cb6952d0b qa: Wait for txindex to avoid race condition (Hodlinator)
9bfb0d75ba10591cc6c9620f9fd1ecc0e55e7a48 qa: Remove unnecessary -txindex args (Hodlinator)
7ac281c19cd3d11f316dbbb3308eabf1ad4f26d6 qa: Add missing coverage of corrupt indexes (Hodlinator)

Pull request description:

  - Add synchronization in 3 places where if the Transaction Index happens to be slow, we get rare test failures when querying it for transactions (one such case experienced on Windows, prompting investigation).
  - Remove unnecessary TxIndex initialization in some tests.
  - Add some test coverage where TxIndex aspect could be tested in feature_init.py.

ACKs for top commit:
  fjahr:
    re-ACK 3301d2cbe8c3b76c97285d75fa59637cb6952d0b
  mzumsande:
    Code Review ACK 3301d2cbe8c3b76c97285d75fa59637cb6952d0b
  furszy:
    Code review ACK 3301d2cbe8c3b76c97285d75fa59637cb6952d0b
  Prabhat1308:
    Concept ACK [`3301d2c`](3301d2cbe8)

Tree-SHA512: 7c2019e38455f344856aaf6b381faafbd88d53dc88d13309deb718c1dcfbee4ccca7c7f1b66917395503a6f94c3b216a007ad432cc8b93d0309db9805f38d602

src/httpserver.cpp

@@ -197,10 +197,10 @@ public:
         return WITH_LOCK(m_mutex, return m_tracker.size());
     }
     //! Wait until there are no more connections with active requests in the tracker
-    void WaitUntilEmpty() const EXCLUSIVE_LOCKS_REQUIRED(!m_mutex)
+    void WaitUntilEmpty(std::chrono::seconds timeout) const EXCLUSIVE_LOCKS_REQUIRED(!m_mutex)
     {
         WAIT_LOCK(m_mutex, lock);
-        m_cv.wait(lock, [this]() EXCLUSIVE_LOCKS_REQUIRED(m_mutex) { return m_tracker.empty(); });
+        m_cv.wait_for(lock, timeout, [this]() EXCLUSIVE_LOCKS_REQUIRED(m_mutex) { return m_tracker.empty(); });
     }
 };
 //! Track active requests
@@ -258,6 +258,8 @@ std::string RequestMethodString(HTTPRequest::RequestMethod m)
     assert(false);
 }
 
+static std::atomic_uint32_t g_request_id{0};
+
 /** HTTP request callback */
 static void http_request_cb(struct evhttp_request* req, void* arg)
 {
@@ -284,7 +286,8 @@ static void http_request_cb(struct evhttp_request* req, void* arg)
             }
         }
     }
-    auto hreq{std::make_unique<HTTPRequest>(req, *static_cast<const util::SignalInterrupt*>(arg))};
+    const uint32_t request_id = g_request_id++;
+    auto hreq{std::make_unique<HTTPRequest>(req, *static_cast<const util::SignalInterrupt*>(arg), request_id, /*replySent=*/false)};
 
     // Early address-based allow check
     if (!ClientAllowed(hreq->GetPeer())) {
@@ -302,8 +305,8 @@ static void http_request_cb(struct evhttp_request* req, void* arg)
         return;
     }
 
-    LogDebug(BCLog::HTTP, "Received a %s request for %s from %s\n",
-             RequestMethodString(hreq->GetRequestMethod()), SanitizeString(hreq->GetURI(), SAFE_CHARS_URI).substr(0, 100), hreq->GetPeer().ToStringAddrPort());
+    LogDebug(BCLog::HTTP, "Received a %s request for %s from %s, id: %d\n",
+             RequestMethodString(hreq->GetRequestMethod()), SanitizeString(hreq->GetURI(), SAFE_CHARS_URI).substr(0, 100), hreq->GetPeer().ToStringAddrPort(), request_id);
 
     // Find registered handler for prefix
     std::string strURI = hreq->GetURI();
@@ -529,32 +532,50 @@ void StopHTTPServer()
         }
         g_thread_http_workers.clear();
     }
-    // Unlisten sockets, these are what make the event loop running, which means
-    // that after this and all connections are closed the event loop will quit.
+    // Unlisten sockets which would otherwise keep the event loop running. Doing
+    // so avoids new connections being created, while existing ones continue
+    // being processed in parallel with this thread until they complete.
     for (evhttp_bound_socket *socket : boundSockets) {
         evhttp_del_accept_socket(eventHTTP, socket);
     }
     boundSockets.clear();
-    {
-        if (const auto n_connections{g_requests.CountActiveConnections()}; n_connections != 0) {
-            LogDebug(BCLog::HTTP, "Waiting for %d connections to stop HTTP server\n", n_connections);
+    // Give clients time to close down TCP connections from their side before we
+    // free eventHTTP, this avoids issues like RemoteDisconnected exceptions in
+    // the test framework.
+    g_requests.WaitUntilEmpty(/*timeout=*/30s);
+    if (auto connections{g_requests.CountActiveConnections()}) {
+        LogWarning("%d remaining HTTP connection(s) after 30s timeout, waiting for longer.", connections);
+        g_requests.WaitUntilEmpty(/*timeout=*/10min);
+        if ((connections = g_requests.CountActiveConnections())) {
+            LogError("%d remaining HTTP connection(s) after long timeout. "
+                     "Aborting to avoid potential use-after-frees from "
+                     "connections still running after freeing eventHTTP.", connections);
+            std::abort();
         }
-        g_requests.WaitUntilEmpty();
     }
     if (eventHTTP) {
-        // Schedule a callback to call evhttp_free in the event base thread, so
-        // that evhttp_free does not need to be called again after the handling
-        // of unfinished request connections that follows.
-        event_base_once(eventBase, -1, EV_TIMEOUT, [](evutil_socket_t, short, void*) {
+        // Schedule a callback to call evhttp_free in the event base thread, as
+        // otherwise eventHTTP often keeps internal events alive, meaning
+        // aforementioned thread would never run out of events and exit.
+        if (event_base_once(eventBase, -1, EV_TIMEOUT, [](evutil_socket_t, short, void*) {
             evhttp_free(eventHTTP);
             eventHTTP = nullptr;
-        }, nullptr, nullptr);
+        }, nullptr, nullptr) != 0) {
+            LogDebug(BCLog::HTTP, "event_base_once failed");
+        }
     }
     if (eventBase) {
         LogDebug(BCLog::HTTP, "Waiting for HTTP event thread to exit\n");
         if (g_thread_http.joinable()) g_thread_http.join();
+        if (eventHTTP) {
+            LogDebug(BCLog::HTTP, "Freeing eventHTTP-event was not picked up by ThreadHTTP before it exited.");
+            evhttp_free(eventHTTP);
+            eventHTTP = nullptr;
+        }
         event_base_free(eventBase);
         eventBase = nullptr;
+    } else {
+        Assume(!g_thread_http.joinable());
     }
     g_work_queue.reset();
     LogDebug(BCLog::HTTP, "Stopped HTTP server\n");
@@ -591,8 +612,8 @@ void HTTPEvent::trigger(struct timeval* tv)
     else
         evtimer_add(ev, tv); // trigger after timeval passed
 }
-HTTPRequest::HTTPRequest(struct evhttp_request* _req, const util::SignalInterrupt& interrupt, bool _replySent)
-    : req(_req), m_interrupt(interrupt), replySent(_replySent)
+HTTPRequest::HTTPRequest(struct evhttp_request* _req, const util::SignalInterrupt& interrupt, uint32_t id, bool _replySent)
+    : req(_req), m_interrupt(interrupt), m_id(id), replySent(_replySent)
 {
 }
 
@@ -653,6 +674,7 @@ void HTTPRequest::WriteReply(int nStatus, std::span<const std::byte> reply)
 {
     assert(!replySent && req);
     if (m_interrupt) {
+        LogDebug(BCLog::HTTP, "Instructing client to close their TCP connection to us (request id %d).", m_id);
         WriteHeader("Connection", "close");
     }
     // Send event to main http thread to send reply message
@@ -660,8 +682,9 @@ void HTTPRequest::WriteReply(int nStatus, std::span<const std::byte> reply)
     assert(evb);
     evbuffer_add(evb, reply.data(), reply.size());
     auto req_copy = req;
-    HTTPEvent* ev = new HTTPEvent(eventBase, true, [req_copy, nStatus]{
+    HTTPEvent* ev = new HTTPEvent(eventBase, true, [req_copy, nStatus, id = m_id](){
         evhttp_send_reply(req_copy, nStatus, nullptr, nullptr);
+        LogDebug(BCLog::HTTP, "Replied to request: %d", id);
         // Re-enable reading from the socket. This is the second part of the libevent
         // workaround above.
         if (event_get_version_number() >= 0x02010600 && event_get_version_number() < 0x02010900) {

src/httpserver.h

@@ -5,6 +5,7 @@
 #ifndef BITCOIN_HTTPSERVER_H
 #define BITCOIN_HTTPSERVER_H
 
+#include <cstdint>
 #include <functional>
 #include <optional>
 #include <span>
@@ -72,10 +73,11 @@ class HTTPRequest
 private:
     struct evhttp_request* req;
     const util::SignalInterrupt& m_interrupt;
+    const uint32_t m_id;
     bool replySent;
 
 public:
-    explicit HTTPRequest(struct evhttp_request* req, const util::SignalInterrupt& interrupt, bool replySent = false);
+    explicit HTTPRequest(struct evhttp_request* req, const util::SignalInterrupt& interrupt, uint32_t id, bool replySent);
     ~HTTPRequest();
 
     enum RequestMethod {

src/test/fuzz/http_request.cpp

@@ -49,7 +49,7 @@ FUZZ_TARGET(http_request)
     }
 
     util::SignalInterrupt interrupt;
-    HTTPRequest http_request{evreq, interrupt, true};
+    HTTPRequest http_request{evreq, interrupt, /*id=*/0, /*replySent=*/true};
     const HTTPRequest::RequestMethod request_method = http_request.GetRequestMethod();
     (void)RequestMethodString(request_method);
     (void)http_request.GetURI();

test/functional/feature_init.py

@@ -88,7 +88,7 @@ class InitTest(BitcoinTestFramework):
 
         args = ['-txindex=1', '-blockfilterindex=1', '-coinstatsindex=1']
         for terminate_line in lines_to_terminate_after:
-            self.log.info(f"Starting node and will exit after line {terminate_line}")
+            self.log.info(f"Starting node and will terminate after line {terminate_line}")
             with node.busy_wait_for_debug_log([terminate_line]):
                 if platform.system() == 'Windows':
                     # CREATE_NEW_PROCESS_GROUP is required in order to be able
@@ -108,12 +108,22 @@ class InitTest(BitcoinTestFramework):
             'blocks/index/*.ldb': 'Error opening block database.',
             'chainstate/*.ldb': 'Error opening coins database.',
             'blocks/blk*.dat': 'Error loading block database.',
+            'indexes/txindex/MANIFEST*': 'LevelDB error: Corruption: CURRENT points to a non-existent file',
+            # Removing these files does not result in a startup error:
+            # 'indexes/blockfilter/basic/*.dat', 'indexes/blockfilter/basic/db/*.*', 'indexes/coinstats/db/*.*',
+            # 'indexes/txindex/*.log', 'indexes/txindex/CURRENT', 'indexes/txindex/LOCK'
         }
 
         files_to_perturb = {
             'blocks/index/*.ldb': 'Error loading block database.',
             'chainstate/*.ldb': 'Error opening coins database.',
             'blocks/blk*.dat': 'Corrupted block database detected.',
+            'indexes/blockfilter/basic/db/*.*': 'LevelDB error: Corruption',
+            'indexes/coinstats/db/*.*': 'LevelDB error: Corruption',
+            'indexes/txindex/*.log': 'LevelDB error: Corruption',
+            'indexes/txindex/CURRENT': 'LevelDB error: Corruption',
+            # Perturbing these files does not result in a startup error:
+            # 'indexes/blockfilter/basic/*.dat', 'indexes/txindex/MANIFEST*', 'indexes/txindex/LOCK'
         }
 
         for file_patt, err_fragment in files_to_delete.items():
@@ -135,9 +145,10 @@ class InitTest(BitcoinTestFramework):
             self.stop_node(0)
 
         self.log.info("Test startup errors after perturbing certain essential files")
+        dirs = ["blocks", "chainstate", "indexes"]
         for file_patt, err_fragment in files_to_perturb.items():
-            shutil.copytree(node.chain_path / "blocks", node.chain_path / "blocks_bak")
-            shutil.copytree(node.chain_path / "chainstate", node.chain_path / "chainstate_bak")
+            for dir in dirs:
+                shutil.copytree(node.chain_path / dir, node.chain_path / f"{dir}_bak")
             target_files = list(node.chain_path.glob(file_patt))
 
             for target_file in target_files:
@@ -151,10 +162,9 @@ class InitTest(BitcoinTestFramework):
 
             start_expecting_error(err_fragment)
 
-            shutil.rmtree(node.chain_path / "blocks")
-            shutil.rmtree(node.chain_path / "chainstate")
-            shutil.move(node.chain_path / "blocks_bak", node.chain_path / "blocks")
-            shutil.move(node.chain_path / "chainstate_bak", node.chain_path / "chainstate")
+            for dir in dirs:
+                shutil.rmtree(node.chain_path / dir)
+                shutil.move(node.chain_path / f"{dir}_bak", node.chain_path / dir)
 
     def init_pid_test(self):
         BITCOIN_PID_FILENAME_CUSTOM = "my_fancy_bitcoin_pid_file.foobar"

test/functional/mempool_accept.py

@@ -45,6 +45,7 @@ from test_framework.util import (
     assert_equal,
     assert_greater_than,
     assert_raises_rpc_error,
+    sync_txindex,
 )
 from test_framework.wallet import MiniWallet
 from test_framework.wallet_util import generate_keypair
@@ -270,6 +271,7 @@ class MempoolAcceptanceTest(BitcoinTestFramework):
 
         self.log.info('A coinbase transaction')
         # Pick the input of the first tx we created, so it has to be a coinbase tx
+        sync_txindex(self, node)
         raw_tx_coinbase_spent = node.getrawtransaction(txid=node.decoderawtransaction(hexstring=raw_tx_in_block)['vin'][0]['txid'])
         tx = tx_from_hex(raw_tx_coinbase_spent)
         self.check_mempool_result(

test/functional/rpc_rawtransaction.py

@@ -34,6 +34,7 @@ from test_framework.util import (
     assert_equal,
     assert_greater_than,
     assert_raises_rpc_error,
+    sync_txindex,
 )
 from test_framework.wallet import (
     getnewdestination,
@@ -70,7 +71,7 @@ class RawTransactionsTest(BitcoinTestFramework):
         self.num_nodes = 3
         self.extra_args = [
             ["-txindex"],
-            ["-txindex"],
+            [],
             ["-fastprune", "-prune=1"],
         ]
         # whitelist peers to speed up tx relay / mempool sync
@@ -109,6 +110,7 @@ class RawTransactionsTest(BitcoinTestFramework):
             self.log.info(f"Test getrawtransaction {'with' if n == 0 else 'without'} -txindex")
 
             if n == 0:
+                sync_txindex(self, self.nodes[n])
                 # With -txindex.
                 # 1. valid parameters - only supply txid
                 assert_equal(self.nodes[n].getrawtransaction(txId), tx['hex'])

test/functional/rpc_txoutproof.py

@@ -12,6 +12,7 @@ from test_framework.test_framework import BitcoinTestFramework
 from test_framework.util import (
     assert_equal,
     assert_raises_rpc_error,
+    sync_txindex,
 )
 from test_framework.wallet import MiniWallet
 
@@ -77,6 +78,7 @@ class MerkleBlockTest(BitcoinTestFramework):
         assert_equal(sorted(self.nodes[0].verifytxoutproof(self.nodes[0].gettxoutproof([txid1, txid2]))), sorted(txlist))
         assert_equal(sorted(self.nodes[0].verifytxoutproof(self.nodes[0].gettxoutproof([txid2, txid1]))), sorted(txlist))
         # We can always get a proof if we have a -txindex
+        sync_txindex(self, self.nodes[1])
         assert_equal(self.nodes[0].verifytxoutproof(self.nodes[1].gettxoutproof([txid_spent])), [txid_spent])
         # We can't get a proof if we specify transactions from different blocks
         assert_raises_rpc_error(-5, "Not all transactions found in specified or retrieved block", self.nodes[0].gettxoutproof, [txid1, txid3])

test/functional/test_framework/util.py

@@ -592,3 +592,10 @@ def find_vout_for_address(node, txid, addr):
         if addr == tx["vout"][i]["scriptPubKey"]["address"]:
             return i
     raise RuntimeError("Vout not found for address: txid=%s, addr=%s" % (txid, addr))
+
+
+def sync_txindex(test_framework, node):
+    test_framework.log.debug("Waiting for node txindex to sync")
+    sync_start = int(time.time())
+    test_framework.wait_until(lambda: node.getindexinfo("txindex")["txindex"]["synced"])
+    test_framework.log.debug(f"Synced in {time.time() - sync_start} seconds")

test/functional/wallet_avoid_mixing_output_types.py

@@ -117,7 +117,6 @@ class AddressInputTypeGrouping(BitcoinTestFramework):
         self.extra_args = [
             [
                 "-addresstype=bech32",
-                "-txindex",
             ],
             [
                 "-addresstype=p2sh-segwit",