From a38cbb70a8b6dc22696f85bef8a8fafedc304025 Mon Sep 17 00:00:00 2001
From: Barry Kane <barry@omnimenu.ie>
Date: Wed, 8 Feb 2023 17:15:23 +0000
Subject: [PATCH] Fixed Thomas's Bug.

In short:
- When a large amount of input was recieved, the server would hang.
- The server would hang on queue->lock for the input queue, in pushQueue().
- Upon debugging, it was revealed that queue->lock was actually false at this time.
- GCC had optimized out the actual loop, leaving it to get stuck even though the variable had changed.
- Adding the volatile keyword to the lock fixed this issue.
---
 Makefile    | 2 +-
 src/queue.c | 3 +++
 src/queue.h | 2 +-
 3 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/Makefile b/Makefile
index 7abf4ec..e1478ab 100644
--- a/Makefile
+++ b/Makefile
@@ -24,6 +24,6 @@ clean:
 	rm -f $(clientobj) $(serverobj) SilverMUDClient SilverMUDServer SilverMUDClientDebug SilverMUDServerDebug
 
 all: clean SilverMUDClient SilverMUDServer
-all: CFLAGS += -Wall -Wextra -Ofast
+all: CFLAGS += -Wall -Wextra -Ofast 
 debug: CFLAGS += -Wall -Wextra -pg -ggdb -Og -D debug
 debug: clean SilverMUDClientDebug SilverMUDServerDebug
diff --git a/src/queue.c b/src/queue.c
index d137525..74ba8e8 100644
--- a/src/queue.c
+++ b/src/queue.c
@@ -157,6 +157,9 @@ void popQueue(queue * queue)
 // Adds data to the back of a queue:
 void pushQueue(queue * queue, void * data, queueDataType type)
 {
+	// Check if the queue is locked:
+	while (queue->lock);
+
 	// Create a new node:
 	queueNode * newNode = malloc(sizeof(queueNode));
 	newNode->type = type;
diff --git a/src/queue.h b/src/queue.h
index c2691df..797c173 100644
--- a/src/queue.h
+++ b/src/queue.h
@@ -37,7 +37,7 @@ typedef struct queueNode
 
 typedef struct queue
 {
-	bool lock;
+	volatile bool lock;
 	size_t itemCount;
 	queueNode * front;
 	queueNode * back;