From 14b880b7083a8eb03f1371aa50df1483f7a074a6 Mon Sep 17 00:00:00 2001
From: Bryan Biedenkapp <gatekeep@gmail.com>
Date: Tue, 13 Aug 2024 16:22:56 -0400
Subject: [PATCH] add some mutex locking for thread safety, ensure addFrame and
 getFrame cannot happen simultaneously;

---
 src/host/dmr/Slot.cpp     |  5 +++++
 src/host/dmr/Slot.h       |  2 ++
 src/host/nxdn/Control.cpp |  9 +++++++++
 src/host/nxdn/Control.h   |  2 ++
 src/host/p25/Control.cpp  | 10 ++++++++++
 src/host/p25/Control.h    |  2 ++
 6 files changed, 30 insertions(+)

diff --git a/src/host/dmr/Slot.cpp b/src/host/dmr/Slot.cpp
index ab74637a..15c22cd7 100644
--- a/src/host/dmr/Slot.cpp
+++ b/src/host/dmr/Slot.cpp
@@ -98,6 +98,7 @@ Slot::Slot(uint32_t slotNo, uint32_t timeout, uint32_t tgHang, uint32_t queueSiz
     m_slotNo(slotNo),
     m_txImmQueue(queueSize, "DMR Imm Slot Frame"),
     m_txQueue(queueSize, "DMR Slot Frame"),
+    m_queueLock(),
     m_rfState(RS_RF_LISTENING),
     m_rfLastDstId(0U),
     m_rfLastSrcId(0U),
@@ -333,6 +334,8 @@ uint32_t Slot::getFrame(uint8_t* data)
 {
     assert(data != nullptr);
 
+    std::lock_guard<std::mutex> lock(m_queueLock);
+
     if (m_txQueue.isEmpty() && m_txImmQueue.isEmpty())
         return 0U;
 
@@ -987,6 +990,8 @@ void Slot::addFrame(const uint8_t *data, bool net, bool imm)
 {
     assert(data != nullptr);
 
+    std::lock_guard<std::mutex> lock(m_queueLock);
+
     if (!net) {
         if (m_netState != RS_NET_IDLE)
             return;
diff --git a/src/host/dmr/Slot.h b/src/host/dmr/Slot.h
index 004b329b..209c522f 100644
--- a/src/host/dmr/Slot.h
+++ b/src/host/dmr/Slot.h
@@ -35,6 +35,7 @@
 #include "network/Network.h"
 
 #include <vector>
+#include <mutex>
 
 namespace dmr
 {
@@ -307,6 +308,7 @@ namespace dmr
 
         RingBuffer<uint8_t> m_txImmQueue;
         RingBuffer<uint8_t> m_txQueue;
+        std::mutex m_queueLock;
 
         RPT_RF_STATE m_rfState;
         uint32_t m_rfLastDstId;
diff --git a/src/host/nxdn/Control.cpp b/src/host/nxdn/Control.cpp
index 6320cc42..20beb50c 100644
--- a/src/host/nxdn/Control.cpp
+++ b/src/host/nxdn/Control.cpp
@@ -42,6 +42,11 @@ const uint8_t SCRAMBLER[] = {
     0x28U, 0x28U, 0x00U, 0x0AU, 0x02U, 0x82U, 0x20U, 0x28U, 0x82U, 0x2AU, 0xAAU, 0x20U, 0x22U, 0x80U,
     0xA8U, 0x8AU, 0x08U, 0xA0U, 0xAAU, 0x02U };
 
+// ---------------------------------------------------------------------------
+//  Static Class Members
+// ---------------------------------------------------------------------------
+
+std::mutex Control::m_queueLock;
 
 // ---------------------------------------------------------------------------
 //  Public Class Members
@@ -482,6 +487,8 @@ uint32_t Control::getFrame(uint8_t* data)
 {
     assert(data != nullptr);
 
+    std::lock_guard<std::mutex> lock(m_queueLock);
+
     if (m_txQueue.isEmpty() && m_txImmQueue.isEmpty())
         return 0U;
 
@@ -825,6 +832,8 @@ void Control::addFrame(const uint8_t *data, bool net, bool imm)
 {
 	assert(data != nullptr);
 
+    std::lock_guard<std::mutex> lock(m_queueLock);
+
     if (!net) {
         if (m_rfTimeout.isRunning() && m_rfTimeout.hasExpired())
             return;
diff --git a/src/host/nxdn/Control.h b/src/host/nxdn/Control.h
index 68e16af6..716413c6 100644
--- a/src/host/nxdn/Control.h
+++ b/src/host/nxdn/Control.h
@@ -43,6 +43,7 @@
 
 #include <cstdio>
 #include <string>
+#include <mutex>
 
 namespace nxdn
 {
@@ -289,6 +290,7 @@ namespace nxdn
 
         RingBuffer<uint8_t> m_txImmQueue;
         RingBuffer<uint8_t> m_txQueue;
+        static std::mutex m_queueLock;
 
         RPT_RF_STATE m_rfState;
         uint32_t m_rfLastDstId;
diff --git a/src/host/p25/Control.cpp b/src/host/p25/Control.cpp
index f02431ca..38befffa 100644
--- a/src/host/p25/Control.cpp
+++ b/src/host/p25/Control.cpp
@@ -37,6 +37,12 @@ const uint8_t MAX_SYNC_BYTES_ERRS = 4U;
 const uint32_t TSBK_PCH_CCH_CNT = 6U;
 const uint32_t MAX_PREAMBLE_TDU_CNT = 64U;
 
+// ---------------------------------------------------------------------------
+//  Static Class Members
+// ---------------------------------------------------------------------------
+
+std::mutex Control::m_queueLock;
+
 // ---------------------------------------------------------------------------
 //  Public Class Members
 // ---------------------------------------------------------------------------
@@ -695,6 +701,8 @@ uint32_t Control::getFrame(uint8_t* data)
 {
     assert(data != nullptr);
 
+    std::lock_guard<std::mutex> lock(m_queueLock);
+
     if (m_txQueue.isEmpty() && m_txImmQueue.isEmpty())
         return 0U;
 
@@ -1133,6 +1141,8 @@ void Control::addFrame(const uint8_t* data, uint32_t length, bool net, bool imm)
 {
     assert(data != nullptr);
 
+    std::lock_guard<std::mutex> lock(m_queueLock);
+
     if (!net) {
         if (m_rfTimeout.isRunning() && m_rfTimeout.hasExpired())
             return;
diff --git a/src/host/p25/Control.h b/src/host/p25/Control.h
index c7cb817e..3c4a2f8e 100644
--- a/src/host/p25/Control.h
+++ b/src/host/p25/Control.h
@@ -47,6 +47,7 @@
 #include <vector>
 #include <unordered_map>
 #include <random>
+#include <mutex>
 
 namespace p25
 {
@@ -312,6 +313,7 @@ namespace p25
 
         RingBuffer<uint8_t> m_txImmQueue;
         RingBuffer<uint8_t> m_txQueue;
+        static std::mutex m_queueLock;
 
         RPT_RF_STATE m_rfState;
         uint32_t m_rfLastDstId;