[+] Missing UNIX flock advisory impl

Source/IO/FS/FileAdvisory.Unix.cpp

@@ -5,3 +5,30 @@
     Date: 2022-1-29
     Author: Reece
 ***/
+#include <Source/RuntimeInternal.hpp>
+#include "FS.hpp"
+#include "FileAdvisory.Unix.hpp"
+#include <sys/file.h>
+
+namespace Aurora::IO::FS
+{
+    bool ApplyDumbAdvisoryLock(int fd, EFileAdvisoryLockLevel level)
+    {
+        int operation = LOCK_NB;
+
+        switch (level)
+        {
+        case EFileAdvisoryLockLevel::eEnumCount:
+        case EFileAdvisoryLockLevel::eNoSafety:
+            return true;
+        case EFileAdvisoryLockLevel::eBlockWrite:
+            operation |= LOCK_SH;
+            break;
+        case EFileAdvisoryLockLevel::eBlockReadWrite:
+            operation |= LOCK_EX;
+            break;
+        }
+
+        return flock(fd, operation) == 0;
+    }
+}

Source/IO/FS/FileAdvisory.Unix.hpp

@@ -0,0 +1,13 @@
+/***
+    Copyright (C) 2022 J Reece Wilson (a/k/a "Reece"). All rights reserved.
+
+    File: FileAdvisory.Unix.hpp
+    Date: 2022-1-29
+    Author: Reece
+***/
+#pragma once
+
+namespace Aurora::IO::FS
+{
+    bool ApplyDumbAdvisoryLock(int fd, EFileAdvisoryLockLevel level);
+}

Source/IO/FS/FileStream.Unix.cpp

@@ -11,7 +11,7 @@
 #include <Source/RuntimeInternal.hpp>
 #include "FS.hpp"
 #include "FileStream.Generic.hpp"
-
+#include "FileAdvisory.Unix.hpp"
 #include <sys/types.h>
 #include <unistd.h>
 #include <fcntl.h>
@@ -312,6 +312,12 @@ namespace Aurora::IO::FS
             return nullptr;
         }
 
+        if (!ApplyDumbAdvisoryLock(fileHandle, lock))
+        {
+            SysPushErrorIO("Couldn't open file: {}. File node (not section) is locked.", path);
+            return nullptr;
+        }
+
         auto stream = _new PosixFileStream();
         if (!stream)
         {