From 14862ec271b1490a67be58e0237c711a90405121 Mon Sep 17 00:00:00 2001
From: Gabriel <gabscoarnec@gmail.com>
Date: Sun, 16 Feb 2025 11:52:45 +0100
Subject: [PATCH] core: Add spinlock code

---
 core/src/lib/spinlock.zig | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)
 create mode 100644 core/src/lib/spinlock.zig

diff --git a/core/src/lib/spinlock.zig b/core/src/lib/spinlock.zig
new file mode 100644
index 0000000..8cc50b2
--- /dev/null
+++ b/core/src/lib/spinlock.zig
@@ -0,0 +1,24 @@
+const std = @import("std");
+const debug = @import("../arch/debug.zig");
+
+pub const SpinLock = struct {
+    lock_value: std.atomic.Value(u32) = std.atomic.Value(u32).init(0),
+
+    pub fn lock(self: *SpinLock) void {
+        while (self.lock_value.cmpxchgWeak(0, 1, .seq_cst, .seq_cst) != null) {}
+    }
+
+    pub fn unlock(self: *SpinLock) void {
+        if (self.lock_value.cmpxchgStrong(1, 0, .seq_cst, .seq_cst) != null) {
+            debug.print("Error: SpinLock.unlock() called on an unlocked lock!\n", .{});
+        }
+    }
+
+    pub fn tryLock(self: *SpinLock) bool {
+        return self.lock_value.cmpxchgStrong(0, 1, .seq_cst, .seq_cst) == null;
+    }
+
+    pub fn isLocked(self: *SpinLock) bool {
+        return self.lock_value.load() != 0;
+    }
+};