replace manual lock/unlock with lock_guard to ensure a lock is held in a scope, and released when a scope is closed;

src/common/lookups/IdenTableLookup.cpp

@@ -7,7 +7,7 @@
 * @package DVM / Common Library
 * @license GPLv2 License (https://opensource.org/licenses/GPL-2.0)
 *
-*   Copyright (C) 2018-2022 Bryan Biedenkapp, N2PLL
+*   Copyright (C) 2018-2022,2024 Bryan Biedenkapp, N2PLL
 *   Copyright (c) 2024 Patrick McDonnell, W3AXL
 *
 */
@@ -21,6 +21,12 @@ using namespace lookups;
 #include <vector>
 #include <fstream>
 
+// ---------------------------------------------------------------------------
+//  Static Class Members
+// ---------------------------------------------------------------------------
+
+std::mutex IdenTableLookup::m_mutex;
+
 // ---------------------------------------------------------------------------
 //  Public Class Members
 // ---------------------------------------------------------------------------
@@ -35,6 +41,15 @@ IdenTableLookup::IdenTableLookup(const std::string& filename, uint32_t reloadTim
     /* stub */
 }
 
+/// <summary>
+/// Clears all entries from the lookup table.
+/// </summary>
+void IdenTableLookup::clear()
+{
+    std::lock_guard<std::mutex> lock(m_mutex);
+    m_table.clear();
+}
+
 /// <summary>
 /// Finds a table entry in this lookup table.
 /// </summary>
@@ -44,15 +59,12 @@ IdenTable IdenTableLookup::find(uint32_t id)
 {
     IdenTable entry;
 
-    m_mutex.lock();
+    std::lock_guard<std::mutex> lock(m_mutex);
-    {
     try {
         entry = m_table.at(id);
     } catch (...) {
         /* stub */
     }
-    }
-    m_mutex.unlock();
 
     float chBandwidthKhz = entry.chBandwidthKhz();
     if (chBandwidthKhz == 0.0F)
@@ -105,8 +117,8 @@ bool IdenTableLookup::load()
     // clear table
     clear();
 
-    m_mutex.lock();
+    std::lock_guard<std::mutex> lock(m_mutex);
-    {
+
     // read lines from file
     std::string line;
     while (std::getline(file, line)) {
@@ -154,8 +166,6 @@ bool IdenTableLookup::load()
             m_table[channelId] = entry;
         }
     }
-    }
-    m_mutex.unlock();
 
     file.close();
 
@@ -174,6 +184,5 @@ bool IdenTableLookup::load()
 /// <returns>True, if lookup table was saved, otherwise false.</returns>
 bool IdenTableLookup::save()
 {
-    /// TODO TODO TODO actually save stuff
     return false;
 }

src/common/lookups/IdenTableLookup.h

@@ -7,7 +7,7 @@
 * @package DVM / Common Library
 * @license GPLv2 License (https://opensource.org/licenses/GPL-2.0)
 *
-*   Copyright (C) 2018-2022 Bryan Biedenkapp, N2PLL
+*   Copyright (C) 2018-2022,2024 Bryan Biedenkapp, N2PLL
 *   Copyright (c) 2024 Patrick McDonnell, W3AXL
 *
 */
@@ -96,6 +96,9 @@ namespace lookups
         /// <summary>Initializes a new instance of the IdenTableLookup class.</summary>
         IdenTableLookup(const std::string& filename, uint32_t reloadTime);
 
+        /// <summary>Clears all entries from the lookup table.</summary>
+        void clear() override;
+
         /// <summary>Finds a table entry in this lookup table.</summary>
         IdenTable find(uint32_t id) override;
         /// <summary>Returns the list of entries in this lookup table.</summary>
@@ -109,6 +112,9 @@ namespace lookups
         /// <summary>Saves the table to the passed lookup table file.</summary>
         /// <returns>True, if lookup table was saved, otherwise false.</returns>
         bool save() override;
+
+    private:
+        static std::mutex m_mutex;
     };
 } // namespace lookups
 

src/common/lookups/LookupTable.h

@@ -7,7 +7,7 @@
 * @package DVM / Common Library
 * @license GPLv2 License (https://opensource.org/licenses/GPL-2.0)
 *
-*   Copyright (C) 2018-2022 Bryan Biedenkapp, N2PLL
+*   Copyright (C) 2018-2022,2024 Bryan Biedenkapp, N2PLL
 *   Copyright (c) 2024 Patrick McDonnell, W3AXL
 *
 */
@@ -98,31 +98,23 @@ namespace lookups
         /// <summary>Clears all entries from the lookup table.</summary>
         virtual void clear()
         {
-            m_mutex.lock();
+            // bryanb: this is not thread-safe and thread saftey should be implemented
-            {
+            // on the derived class
             m_table.clear();
         }
-            m_mutex.unlock();
-        }
 
         /// <summary>Helper to check if this lookup table has the specified unique ID.</summary>
         /// <param name="id">Unique ID to check for.</param>
         /// <returns>True, if the lookup table has an entry by the specified unique ID, otherwise false.</returns>
         virtual bool hasEntry(uint32_t id)
-        {
-            m_mutex.lock();
         {
             try {
                 m_table.at(id);
-                    m_mutex.unlock();
                 return true;
             }
             catch (...) {
-                    m_mutex.unlock();
                 return false;
             }
-            }
-            m_mutex.unlock();
 
             return false;
         }
@@ -140,7 +132,6 @@ namespace lookups
         std::string m_filename;
         uint32_t m_reloadTime;
         std::unordered_map<uint32_t, T> m_table;
-        std::mutex m_mutex;
         bool m_stop;
 
         /// <summary>Loads the table from the passed lookup table file.</summary>

src/common/lookups/RadioIdLookup.cpp

@@ -24,6 +24,12 @@ using namespace lookups;
 #include <vector>
 #include <fstream>
 
+// ---------------------------------------------------------------------------
+//  Static Class Members
+// ---------------------------------------------------------------------------
+
+std::mutex RadioIdLookup::m_mutex;
+
 // ---------------------------------------------------------------------------
 //  Public Class Members
 // ---------------------------------------------------------------------------
@@ -40,6 +46,15 @@ RadioIdLookup::RadioIdLookup(const std::string& filename, uint32_t reloadTime, b
     /* stub */
 }
 
+/// <summary>
+/// Clears all entries from the lookup table.
+/// </summary>
+void RadioIdLookup::clear()
+{
+    std::lock_guard<std::mutex> lock(m_mutex);
+    m_table.clear();
+}
+
 /// <summary>
 /// Toggles the specified radio ID enabled or disabled.
 /// </summary>
@@ -65,8 +80,7 @@ void RadioIdLookup::addEntry(uint32_t id, bool enabled, const std::string& alias
 
     RadioId entry = RadioId(enabled, false, alias);
 
-    m_mutex.lock();
+    std::lock_guard<std::mutex> lock(m_mutex);
-    {
     try {
         RadioId _entry = m_table.at(id);
 
@@ -79,8 +93,6 @@ void RadioIdLookup::addEntry(uint32_t id, bool enabled, const std::string& alias
         m_table[id] = entry;
     }
 }
-    m_mutex.unlock();
-}
 
 /// <summary>
 /// Erases an existing entry from the lookup table by the specified unique ID.
@@ -88,8 +100,7 @@ void RadioIdLookup::addEntry(uint32_t id, bool enabled, const std::string& alias
 /// <param name="id">Unique ID to erase.</param>
 void RadioIdLookup::eraseEntry(uint32_t id)
 {
-    m_mutex.lock();
+    std::lock_guard<std::mutex> lock(m_mutex);
-    {
     try {
         m_table.at(id);
         m_table.erase(id);
@@ -97,8 +108,6 @@ void RadioIdLookup::eraseEntry(uint32_t id)
         /* stub */
     }
 }
-    m_mutex.unlock();
-}
 
 /// <summary>
 /// Finds a table entry in this lookup table.
@@ -113,15 +122,12 @@ RadioId RadioIdLookup::find(uint32_t id)
         return RadioId(true, false);
     }
 
-    m_mutex.lock();
+    std::lock_guard<std::mutex> lock(m_mutex);
-    {
     try {
         entry = m_table.at(id);
     } catch (...) {
         entry = RadioId(false, true);
     }
-    }
-    m_mutex.unlock();
 
     return entry;
 }
@@ -166,8 +172,8 @@ bool RadioIdLookup::load()
     // clear table
     clear();
 
-    m_mutex.lock();
+    std::lock_guard<std::mutex> lock(m_mutex);
-    {
+
     // read lines from file
     std::string line;
     while (std::getline(file, line)) {
@@ -209,8 +215,6 @@ bool RadioIdLookup::load()
             }
         }
     }
-    }
-    m_mutex.unlock();
 
     file.close();
 
@@ -244,8 +248,8 @@ bool RadioIdLookup::save()
     // Counter for lines written
     unsigned int lines = 0;
 
-    m_mutex.lock();
+    std::lock_guard<std::mutex> lock(m_mutex);
-    {
+
     // String for writing
     std::string line;
     // iterate over each entry in the RID lookup and write it to the open file
@@ -268,8 +272,6 @@ bool RadioIdLookup::save()
         // Increment
         lines++;
     }
-    }
-    m_mutex.unlock();
 
     file.close();
 

src/common/lookups/RadioIdLookup.h

@@ -9,7 +9,7 @@
 * @license GPLv2 License (https://opensource.org/licenses/GPL-2.0)
 *
 *   Copyright (C) 2016 Jonathan Naylor, G4KLX
-*   Copyright (C) 2017-2022 Bryan Biedenkapp, N2PLL
+*   Copyright (C) 2017-2022,2024 Bryan Biedenkapp, N2PLL
 *   Copyright (c) 2024 Patrick McDonnell, W3AXL
 *
 */
@@ -114,6 +114,9 @@ namespace lookups
         /// <summary>Initializes a new instance of the RadioIdLookup class.</summary>
         RadioIdLookup(const std::string& filename, uint32_t reloadTime, bool ridAcl);
 
+        /// <summary>Clears all entries from the lookup table.</summary>
+        void clear() override;
+
         /// <summary>Toggles the specified radio ID enabled or disabled.</summary>
         void toggleEntry(uint32_t id, bool enabled);
 
@@ -141,6 +144,9 @@ namespace lookups
         /// <summary>Saves the table to the passed lookup table file.</summary>
         /// <returns>True, if lookup table was saved, otherwise false.</returns>
         bool save() override;
+
+    private:
+        static std::mutex m_mutex;
     };
 } // namespace lookups
 

src/common/lookups/TalkgroupRulesLookup.cpp

@@ -21,6 +21,12 @@ using namespace lookups;
 #include <string>
 #include <vector>
 
+// ---------------------------------------------------------------------------
+//  Static Class Members
+// ---------------------------------------------------------------------------
+
+std::mutex TalkgroupRulesLookup::m_mutex;
+
 // ---------------------------------------------------------------------------
 //  Public Class Members
 // ---------------------------------------------------------------------------
@@ -105,12 +111,9 @@ bool TalkgroupRulesLookup::read()
 /// </summary>
 void TalkgroupRulesLookup::clear()
 {
-    m_mutex.lock();
+    std::lock_guard<std::mutex> lock(m_mutex);
-    {
     m_groupVoice.clear();
 }
-    m_mutex.unlock();
-}
 
 /// <summary>
 /// Adds a new entry to the lookup table by the specified unique ID.
@@ -126,8 +129,7 @@ void TalkgroupRulesLookup::addEntry(uint32_t id, uint8_t slot, bool enabled)
     source.tgSlot(slot);
     config.active(enabled);
 
-    m_mutex.lock();
+    std::lock_guard<std::mutex> lock(m_mutex);
-    {
     auto it = std::find_if(m_groupVoice.begin(), m_groupVoice.end(),
         [&](TalkgroupRuleGroupVoice x)
         {
@@ -159,8 +161,6 @@ void TalkgroupRulesLookup::addEntry(uint32_t id, uint8_t slot, bool enabled)
         m_groupVoice.push_back(entry);
     }
 }
-    m_mutex.unlock();
-}
 
 /// <summary>
 /// Adds a new entry to the lookup table by the specified unique ID.
@@ -175,8 +175,7 @@ void TalkgroupRulesLookup::addEntry(TalkgroupRuleGroupVoice groupVoice)
     uint32_t id = entry.source().tgId();
     uint8_t slot = entry.source().tgSlot();
 
-    m_mutex.lock();
+    std::lock_guard<std::mutex> lock(m_mutex);
-    {
     auto it = std::find_if(m_groupVoice.begin(), m_groupVoice.end(),
         [&](TalkgroupRuleGroupVoice x)
         {
@@ -193,8 +192,6 @@ void TalkgroupRulesLookup::addEntry(TalkgroupRuleGroupVoice groupVoice)
         m_groupVoice.push_back(entry);
     }
 }
-    m_mutex.unlock();
-}
 
 /// <summary>
 /// Erases an existing entry from the lookup table by the specified unique ID.
@@ -203,15 +200,12 @@ void TalkgroupRulesLookup::addEntry(TalkgroupRuleGroupVoice groupVoice)
 /// <param name="slot">DMR slot this talkgroup is valid on.</param>
 void TalkgroupRulesLookup::eraseEntry(uint32_t id, uint8_t slot)
 {
-    m_mutex.lock();
+    std::lock_guard<std::mutex> lock(m_mutex);
-    {
     auto it = std::find_if(m_groupVoice.begin(), m_groupVoice.end(), [&](TalkgroupRuleGroupVoice x) { return x.source().tgId() == id && x.source().tgSlot() == slot; });
     if (it != m_groupVoice.end()) {
         m_groupVoice.erase(it);
     }
 }
-    m_mutex.unlock();
-}
 
 /// <summary>
 /// Finds a table entry in this lookup table.
@@ -223,8 +217,7 @@ TalkgroupRuleGroupVoice TalkgroupRulesLookup::find(uint32_t id, uint8_t slot)
 {
     TalkgroupRuleGroupVoice entry;
 
-    m_mutex.lock();
+    std::lock_guard<std::mutex> lock(m_mutex);
-    {
     auto it = std::find_if(m_groupVoice.begin(), m_groupVoice.end(),
         [&](TalkgroupRuleGroupVoice x)
         {
@@ -239,8 +232,6 @@ TalkgroupRuleGroupVoice TalkgroupRulesLookup::find(uint32_t id, uint8_t slot)
     } else {
         entry = TalkgroupRuleGroupVoice();
     }
-    }
-    m_mutex.unlock();
 
     return entry;
 }
@@ -256,8 +247,7 @@ TalkgroupRuleGroupVoice TalkgroupRulesLookup::findByRewrite(uint32_t peerId, uin
 {
     TalkgroupRuleGroupVoice entry;
 
-    m_mutex.lock();
+    std::lock_guard<std::mutex> lock(m_mutex);
-    {
     auto it = std::find_if(m_groupVoice.begin(), m_groupVoice.end(),
         [&](TalkgroupRuleGroupVoice x)
         {
@@ -284,8 +274,6 @@ TalkgroupRuleGroupVoice TalkgroupRulesLookup::findByRewrite(uint32_t peerId, uin
     } else {
         entry = TalkgroupRuleGroupVoice();
     }
-    }
-    m_mutex.unlock();
 
     return entry;
 }
@@ -336,8 +324,7 @@ bool TalkgroupRulesLookup::load()
     // clear table
     clear();
 
-    m_mutex.lock();
+    std::lock_guard<std::mutex> lock(m_mutex);
-    {
     yaml::Node& groupVoiceList = m_rules["groupVoice"];
 
     if (groupVoiceList.size() == 0U) {
@@ -365,8 +352,6 @@ bool TalkgroupRulesLookup::load()
 
         ::LogInfoEx(LOG_HOST, "Talkgroup NAME: %s SRC_TGID: %u SRC_TS: %u ACTIVE: %u PARROT: %u INCLUSIONS: %u EXCLUSIONS: %u REWRITES: %u", groupName.c_str(), tgId, tgSlot, active, parrot, incCount, excCount, rewrCount);
     }
-    }
-    m_mutex.unlock();
 
     size_t size = m_groupVoice.size();
     if (size == 0U)
@@ -388,7 +373,7 @@ bool TalkgroupRulesLookup::save()
         return false;
     }
 
-    m_mutex.lock();
+    std::lock_guard<std::mutex> lock(m_mutex);
     
     // New list for our new group voice rules
     yaml::Node groupVoiceList;
@@ -405,8 +390,6 @@ bool TalkgroupRulesLookup::save()
     // Set the new rules
     newRules["groupVoice"] = groupVoiceList;
 
-    m_mutex.unlock();
-
     // Make sure we actually did stuff right
     if (newRules["groupVoice"].size() != m_groupVoice.size()) {
         LogError(LOG_HOST, "Generated YAML node for group lists did not match loaded group size! (%u != %u)", newRules["groupVoice"].size(), m_groupVoice.size());

src/common/lookups/TalkgroupRulesLookup.h

@@ -371,7 +371,7 @@ namespace lookups
 
         bool m_acl;
 
-        std::mutex m_mutex;
+        static std::mutex m_mutex;
         bool m_stop;
 
         /// <summary>Loads the table from the passed lookup table file.</summary>

src/common/network/RawFrameQueue.cpp

@@ -21,6 +21,12 @@ using namespace network;
 #include <cassert>
 #include <cstring>
 
+// ---------------------------------------------------------------------------
+//  Static Class Members
+// ---------------------------------------------------------------------------
+
+std::mutex RawFrameQueue::m_flushMutex;
+
 // ---------------------------------------------------------------------------
 //  Public Class Members
 // ---------------------------------------------------------------------------
@@ -32,7 +38,6 @@ using namespace network;
 /// <param name="debug"></param>
 RawFrameQueue::RawFrameQueue(udp::Socket* socket, bool debug) :
     m_socket(socket),
-    m_flushMutex(),
     m_buffers(),
     m_debug(debug)
 {
@@ -147,17 +152,15 @@ void RawFrameQueue::enqueueMessage(const uint8_t* message, uint32_t length, sock
 bool RawFrameQueue::flushQueue()
 {
     bool ret = true;
-    m_flushMutex.lock();
+    std::lock_guard<std::mutex> lock(m_flushMutex);
-    {
+
     if (m_buffers.empty()) {
-            m_flushMutex.unlock();
         return false;
     }
 
     // bryanb: this is the same as above -- but for some assinine reason prevents
     // weirdness
     if (m_buffers.size() == 0U) {
-            m_flushMutex.unlock();
         return false;
     }
 
@@ -170,9 +173,6 @@ bool RawFrameQueue::flushQueue()
     }
 
     deleteBuffers();
-    }
-    m_flushMutex.unlock();
-
     return ret;
 }
 

src/common/network/RawFrameQueue.h

@@ -59,7 +59,7 @@ namespace network
         uint32_t m_addrLen;
         udp::Socket* m_socket;
 
-        std::mutex m_flushMutex;
+        static std::mutex m_flushMutex;
         udp::BufferVector m_buffers;
 
         bool m_debug;

src/fne/network/FNENetwork.cpp

@@ -37,6 +37,12 @@ const uint32_t MAX_HARD_CONN_CAP = 250U;
 const uint8_t MAX_PEER_LIST_BEFORE_FLUSH = 10U;
 const uint32_t MAX_RID_LIST_CHUNK = 50U;
 
+// ---------------------------------------------------------------------------
+//  Static Class Members
+// ---------------------------------------------------------------------------
+
+std::mutex FNENetwork::m_peerMutex;
+
 // ---------------------------------------------------------------------------
 //  Public Class Members
 // ---------------------------------------------------------------------------
@@ -80,7 +86,6 @@ FNENetwork::FNENetwork(HostFNE* host, const std::string& address, uint16_t port,
     m_ridLookup(nullptr),
     m_tidLookup(nullptr),
     m_status(NET_STAT_INVALID),
-    m_peerMutex(),
     m_peers(),
     m_peerAffiliations(),
     m_maintainenceTimer(1000U, pingTime),
@@ -975,19 +980,15 @@ void* FNENetwork::threadedNetworkRx(void* arg)
 /// <returns></returns>
 bool FNENetwork::erasePeerAffiliations(uint32_t peerId)
 {
-    m_peerMutex.lock();
+    std::lock_guard<std::mutex> lock(m_peerMutex);
-    {
     auto it = std::find_if(m_peerAffiliations.begin(), m_peerAffiliations.end(), [&](PeerAffiliationMapPair x) { return x.first == peerId; });
     if (it != m_peerAffiliations.end()) {
         lookups::AffiliationLookup* aff = m_peerAffiliations[peerId];
         m_peerAffiliations.erase(peerId);
         delete aff;
 
-            m_peerMutex.unlock();
         return true;
     }
-    }
-    m_peerMutex.unlock();
 
     return false;
 }
@@ -999,16 +1000,12 @@ bool FNENetwork::erasePeerAffiliations(uint32_t peerId)
 /// <returns></returns>
 bool FNENetwork::erasePeer(uint32_t peerId)
 {
-    m_peerMutex.lock();
+    std::lock_guard<std::mutex> lock(m_peerMutex);
-    {
     auto it = std::find_if(m_peers.begin(), m_peers.end(), [&](PeerMapPair x) { return x.first == peerId; });
     if (it != m_peers.end()) {
         m_peers.erase(peerId);
-            m_peerMutex.unlock();
         return true;
     }
-    }
-    m_peerMutex.unlock();
 
     return false;
 }

src/fne/network/FNENetwork.h

@@ -270,7 +270,7 @@ namespace network
 
         NET_CONN_STATUS m_status;
 
-        std::mutex m_peerMutex;
+        static std::mutex m_peerMutex;
         typedef std::pair<const uint32_t, network::FNEPeerConnection*> PeerMapPair;
         std::unordered_map<uint32_t, FNEPeerConnection*> m_peers;
         typedef std::pair<const uint32_t, lookups::AffiliationLookup*> PeerAffiliationMapPair;

src/host/Host.cpp

@@ -714,7 +714,7 @@ int Host::run()
     }
 
     bool hasTxShutdown = false;
-    std::mutex clockingMutex;
+    static std::mutex clockingMutex;
 
     // Macro to start DMR duplex idle transmission (or beacon)
     #define START_DMR_DUPLEX_IDLE(x)                                                                                    \
@@ -734,8 +734,10 @@ int Host::run()
         if (dmr != nullptr) {
             LogDebug(LOG_HOST, "DMR, started slot 1 frame processor (modem write)");
             while (!g_killed) {
-                clockingMutex.lock();
+                // scope is intentional
                 {
+                    std::lock_guard<std::mutex> lock(clockingMutex);
+
                     // ------------------------------------------------------
                     //  -- Write to Modem Processing                      --
                     // ------------------------------------------------------
@@ -757,7 +759,6 @@ int Host::run()
                         }
                     });
                 }
-                clockingMutex.unlock();
 
                 if (m_state != STATE_IDLE)
                     Thread::sleep(m_activeTickDelay);
@@ -776,8 +777,10 @@ int Host::run()
         if (dmr != nullptr) {
             LogDebug(LOG_HOST, "DMR, started slot 2 frame processor (modem write)");
             while (!g_killed) {
-                clockingMutex.lock();
+                // scope is intentional
                 {
+                    std::lock_guard<std::mutex> lock(clockingMutex);
+
                     // ------------------------------------------------------
                     //  -- Write to Modem Processing                      --
                     // ------------------------------------------------------
@@ -799,7 +802,6 @@ int Host::run()
                         }
                     });
                 }
-                clockingMutex.unlock();
 
                 if (m_state != STATE_IDLE)
                     Thread::sleep(m_activeTickDelay);
@@ -819,8 +821,10 @@ int Host::run()
         if (p25 != nullptr) {
             LogDebug(LOG_HOST, "P25, started frame processor (modem write)");
             while (!g_killed) {
-                clockingMutex.lock();
+                // scope is intentional
                 {
+                    std::lock_guard<std::mutex> lock(clockingMutex);
+
                     // ------------------------------------------------------
                     //  -- Write to Modem Processing                      --
                     // ------------------------------------------------------
@@ -839,7 +843,6 @@ int Host::run()
                         }
                     });
                 }
-                clockingMutex.unlock();
 
                 if (m_state != STATE_IDLE)
                     Thread::sleep(m_activeTickDelay);
@@ -859,8 +862,10 @@ int Host::run()
         if (nxdn != nullptr) {
             LogDebug(LOG_HOST, "NXDN, started frame processor (modem write)");
             while (!g_killed) {
-                clockingMutex.lock();
+                // scope is intentional
                 {
+                    std::lock_guard<std::mutex> lock(clockingMutex);
+
                     // ------------------------------------------------------
                     //  -- Write to Modem Processing                      --
                     // ------------------------------------------------------
@@ -879,7 +884,6 @@ int Host::run()
                         }
                     });
                 }
-                clockingMutex.unlock();
 
                 if (m_state != STATE_IDLE)
                     Thread::sleep(m_activeTickDelay);
@@ -928,8 +932,10 @@ int Host::run()
             }
         }
 
-        clockingMutex.lock();
+        // scope is intentional
         {
+            std::lock_guard<std::mutex> lock(clockingMutex);
+
             // ------------------------------------------------------
             //  -- Modem Clocking                                 --
             // ------------------------------------------------------
@@ -939,7 +945,6 @@ int Host::run()
 
             m_modem->clock(ms);
         }
-        clockingMutex.unlock();
 
         // ------------------------------------------------------
         //  -- Read from Modem Processing                     --
@@ -1057,7 +1062,7 @@ int Host::run()
 
                 LogDebug(LOG_HOST, "CW, start transmitting");
                 m_isTxCW = true;
-                clockingMutex.lock();
+                std::lock_guard<std::mutex> lock(clockingMutex);
 
                 setState(STATE_IDLE);
                 m_modem->sendCWId(m_cwCallsign);
@@ -1088,7 +1093,6 @@ int Host::run()
                         Thread::sleep(CW_IDLE_SLEEP_MS);
                 } while (true);
 
-                clockingMutex.unlock();
                 m_isTxCW = false;
                 m_cwIdTimer.setTimeout(m_cwIdTime);
                 m_cwIdTimer.start();