Merge 51436f85a2bfcb7874a0c3b12add2df19ff18a3b into 5f4422d68dc3530c353af1f87499de1c864b60ad

src/init.cpp

@@ -1134,11 +1134,6 @@ static bool LockDirectory(const fs::path& dir, bool probeOnly)
     } // no default case, so the compiler can warn about missing cases
     assert(false);
 }
-static bool LockDirectories(bool probeOnly)
-{
-    return LockDirectory(gArgs.GetDataDirNet(), probeOnly) && \
-           LockDirectory(gArgs.GetBlocksDirPath(), probeOnly);
-}
 
 bool AppInitSanityChecks(const kernel::Context& kernel)
 {
@@ -1156,7 +1151,8 @@ bool AppInitSanityChecks(const kernel::Context& kernel)
     // Probe the directory locks to give an early error message, if possible
     // We cannot hold the directory locks here, as the forking for daemon() hasn't yet happened,
     // and a fork will cause weird behavior to them.
-    return LockDirectories(true);
+    return LockDirectory(gArgs.GetDataDirNet(), /*probeOnly=*/true)
+        && LockDirectory(gArgs.GetBlocksDirPath(), /*probeOnly=*/true);
 }
 
 bool AppInitLockDirectories()
@@ -1164,11 +1160,7 @@ bool AppInitLockDirectories()
     // After daemonization get the directory locks again and hold on to them until exit
     // This creates a slight window for a race condition to happen, however this condition is harmless: it
     // will at most make us exit without printing a message to console.
-    if (!LockDirectories(false)) {
-        // Detailed error printed inside LockDirectory
-        return false;
-    }
-    return true;
+    return LockDirectory(gArgs.GetDataDirNet(), /*probeOnly=*/false);
 }
 
 bool AppInitInterfaces(NodeContext& node)

src/init/common.cpp

@@ -115,9 +115,10 @@ bool StartLogging(const ArgsManager& args)
     }
 
     if (!LogInstance().m_log_timestamps)
-        LogPrintf("Startup time: %s\n", FormatISO8601DateTime(GetTime()));
-    LogPrintf("Default data directory %s\n", fs::PathToString(GetDefaultDataDir()));
-    LogPrintf("Using data directory %s\n", fs::PathToString(gArgs.GetDataDirNet()));
+        LogInfo("Startup time: %s", FormatISO8601DateTime(GetTime()));
+    LogInfo("Default data directory %s", fs::PathToString(GetDefaultDataDir()));
+    LogInfo("Using data directory %s", fs::PathToString(gArgs.GetDataDirNet()));
+    LogInfo("Using blocks directory %s", fs::PathToString(gArgs.GetBlocksDirPath()));
 
     // Only log conf file usage message if conf file actually exists.
     fs::path config_file_path = args.GetConfigFilePath();

src/node/blockstorage.cpp

@@ -31,6 +31,7 @@
 #include <util/batchpriority.h>
 #include <util/check.h>
 #include <util/fs.h>
+#include <util/fs_helpers.h>
 #include <util/signalinterrupt.h>
 #include <util/strencodings.h>
 #include <util/translation.h>
@@ -1150,7 +1151,8 @@ static auto InitBlocksdirXorKey(const BlockManager::Options& opts)
 }
 
 BlockManager::BlockManager(const util::SignalInterrupt& interrupt, Options opts)
-    : m_prune_mode{opts.prune_target > 0},
+    : m_blocks_dir_lock{DirectoryLock(opts.blocks_dir, "blocks")},
+      m_prune_mode{opts.prune_target > 0},
       m_xor_key{InitBlocksdirXorKey(opts)},
       m_opts{std::move(opts)},
       m_block_file_seq{FlatFileSeq{m_opts.blocks_dir, "blk", m_opts.fast_prune ? 0x4000 /* 16kB */ : BLOCKFILE_CHUNK_SIZE}},

src/node/blockstorage.h

@@ -18,6 +18,7 @@
 #include <sync.h>
 #include <uint256.h>
 #include <util/fs.h>
+#include <util/fs_helpers.h>
 #include <util/hasher.h>
 
 #include <array>
@@ -127,7 +128,6 @@ struct BlockfileCursor {
 
 std::ostream& operator<<(std::ostream& os, const BlockfileCursor& cursor);
 
-
 /**
  * Maintains a tree of blocks (stored in `m_block_index`) which is consulted
  * to determine where the most-work tip is.
@@ -141,6 +141,7 @@ class BlockManager
     friend ChainstateManager;
 
 private:
+    DirectoryLock m_blocks_dir_lock;
     const CChainParams& GetParams() const { return m_opts.chainparams; }
     const Consensus::Params& GetConsensus() const { return m_opts.chainparams.GetConsensus(); }
     /**

src/test/util_tests.cpp

@@ -1244,13 +1244,13 @@ BOOST_AUTO_TEST_CASE(test_LockDirectory)
     BOOST_CHECK_EQUAL(util::LockDirectory(dirname, lockname), util::LockResult::Success);
 
     // Another lock on the directory from the same thread should succeed
-    BOOST_CHECK_EQUAL(util::LockDirectory(dirname, lockname), util::LockResult::Success);
+    BOOST_CHECK_EQUAL(util::LockDirectory(dirname, lockname), util::LockResult::ErrorLock);
 
     // Another lock on the directory from a different thread within the same process should succeed
     util::LockResult threadresult;
     std::thread thr([&] { threadresult = util::LockDirectory(dirname, lockname); });
     thr.join();
-    BOOST_CHECK_EQUAL(threadresult, util::LockResult::Success);
+    BOOST_CHECK_EQUAL(threadresult, util::LockResult::ErrorLock);
 #ifndef WIN32
     // Try to acquire lock in child process while we're holding it, this should fail.
     BOOST_CHECK_EQUAL(write(fd[1], &LockCommand, 1), 1);
@@ -1291,6 +1291,30 @@ BOOST_AUTO_TEST_CASE(test_LockDirectory)
     BOOST_CHECK_EQUAL(processstatus, 0);
     BOOST_CHECK_EQUAL(util::LockDirectory(dirname, lockname, true), util::LockResult::Success);
 
+    {
+        auto lock{DirectoryLock(dirname, "test")};
+        BOOST_CHECK_THROW(DirectoryLock(dirname, "test"), std::runtime_error);
+    }
+    {
+        BOOST_CHECK_NO_THROW(DirectoryLock(dirname, "test"));
+    }
+
+    {
+        DirectoryLock lock1(dirname, "test");
+        DirectoryLock lock2(std::move(lock1));
+        BOOST_CHECK_THROW(DirectoryLock(dirname, "test"), std::runtime_error);
+    }
+
+    {
+        auto dirname_move = dirname / "move";
+        fs::create_directories(dirname_move);
+        DirectoryLock lock1(dirname, "test");
+        DirectoryLock lock2(dirname_move, "test");
+        lock2 = std::move(lock1);
+        BOOST_CHECK_THROW(DirectoryLock(dirname, "test"), std::runtime_error);
+        BOOST_CHECK_NO_THROW(DirectoryLock(dirname_move, "test"));
+    }
+
     // Restore SIGCHLD
     signal(SIGCHLD, old_handler);
     BOOST_CHECK_EQUAL(close(fd[1]), 0); // Close our side of the socketpair

src/util/fs_helpers.cpp

@@ -11,6 +11,7 @@
 #include <sync.h>
 #include <util/fs.h>
 #include <util/syserror.h>
+#include <util/translation.h>
 
 #include <cerrno>
 #include <fstream>
@@ -57,7 +58,8 @@ LockResult LockDirectory(const fs::path& directory, const fs::path& lockfile_nam
 
     // If a lock for this directory already exists in the map, don't try to re-lock it
     if (dir_locks.count(fs::PathToString(pathLockFile))) {
-        return LockResult::Success;
+        LogError("Error while attempting to lock directory %s: Lock already taken", fs::PathToString(directory));
+        return LockResult::ErrorLock;
     }
 
     // Create empty lock file if it doesn't exist.
@@ -90,6 +92,50 @@ void ReleaseDirectoryLocks()
     dir_locks.clear();
 }
 
+DirectoryLock::DirectoryLock(fs::path dir_path, std::string name)
+    : m_path{dir_path},
+      m_name{name}
+{
+    // Ensures only a single lock is taken on the provided directory.
+    switch (util::LockDirectory(m_path, ".lock", false)) {
+    case util::LockResult::ErrorWrite:
+        throw std::runtime_error(strprintf(_("Cannot write to %s directory '%s'; check permissions."), m_name, fs::PathToString(m_path)).original);
+    case util::LockResult::ErrorLock:
+        throw std::runtime_error(strprintf(_("Cannot obtain a lock on %s directory %s. %s is probably already running."), m_name, fs::PathToString(m_path), CLIENT_NAME).original);
+    case util::LockResult::Success:
+        return;
+    } // no default case, so the compiler can warn about missing cases
+    assert(false);
+}
+
+DirectoryLock::DirectoryLock(DirectoryLock&& other) noexcept
+    : m_path{std::move(other.m_path)},
+      m_name{std::move(other.m_name)}
+{
+    other.m_path.clear();
+    other.m_name.clear();
+}
+
+DirectoryLock& DirectoryLock::operator=(DirectoryLock&& other) noexcept
+{
+    if (this != &other) {
+        if (!m_path.empty()) {
+            UnlockDirectory(m_path, ".lock");
+        }
+        m_path = std::move(other.m_path);
+        other.m_path.clear();
+        m_name = std::move(other.m_name);
+        other.m_name.clear();
+    }
+    return *this;
+}
+
+
+DirectoryLock::~DirectoryLock()
+{
+    if (!m_path.empty()) UnlockDirectory(m_path, ".lock");
+}
+
 bool CheckDiskSpace(const fs::path& dir, uint64_t additional_bytes)
 {
     constexpr uint64_t min_disk_space = 52428800; // 50 MiB

src/util/fs_helpers.h

@@ -45,6 +45,23 @@ enum class LockResult {
 [[nodiscard]] LockResult LockDirectory(const fs::path& directory, const fs::path& lockfile_name, bool probe_only = false);
 } // namespace util
 void UnlockDirectory(const fs::path& directory, const fs::path& lockfile_name);
+
+class DirectoryLock
+{
+    fs::path m_path;
+    std::string m_name;
+
+public:
+    explicit DirectoryLock(fs::path dir_path, std::string name);
+    ~DirectoryLock();
+
+    DirectoryLock(const DirectoryLock&) = delete;
+    DirectoryLock& operator=(const DirectoryLock&) = delete;
+
+    DirectoryLock(DirectoryLock&& other) noexcept;
+    DirectoryLock& operator=(DirectoryLock&& other) noexcept;
+};
+
 bool CheckDiskSpace(const fs::path& dir, uint64_t additional_bytes = 0);
 
 /** Get the size of a file by scanning it.