From b1f9f68e87a4a29c42e21e3c1ffaaf1eff0b927a Mon Sep 17 00:00:00 2001
From: Mitchell Hashimoto <mitchell.hashimoto@gmail.com>
Date: Thu, 21 Apr 2022 15:57:45 -0700
Subject: [PATCH] libuv: Sem

---
 src/libuv/Sem.zig  | 35 +++++++++++++++++++++++++++++++++++
 src/libuv/main.zig |  2 ++
 2 files changed, 37 insertions(+)
 create mode 100644 src/libuv/Sem.zig

diff --git a/src/libuv/Sem.zig b/src/libuv/Sem.zig
new file mode 100644
index 000000000..89bfc6d97
--- /dev/null
+++ b/src/libuv/Sem.zig
@@ -0,0 +1,35 @@
+//! Semaphores implemented via libuv.
+const Sem = @This();
+
+const std = @import("std");
+const Allocator = std.mem.Allocator;
+const testing = std.testing;
+const c = @import("c.zig");
+const errors = @import("error.zig");
+
+sem: *c.uv_sem_t,
+
+pub fn init(alloc: Allocator, value: u32) !Sem {
+    const sem = try alloc.create(c.uv_sem_t);
+    try errors.convertError(c.uv_sem_init(sem, value));
+    return Sem{ .sem = sem };
+}
+
+pub fn deinit(self: *Sem, alloc: Allocator) void {
+    c.uv_sem_destroy(self.sem);
+    alloc.destroy(self.sem);
+    self.* = undefined;
+}
+
+pub fn post(self: Sem) void {
+    c.uv_sem_post(self.sem);
+}
+
+pub fn wait(self: Sem) void {
+    c.uv_sem_wait(self.sem);
+}
+
+test {
+    var sem = try init(testing.allocator, 0);
+    defer sem.deinit(testing.allocator);
+}
diff --git a/src/libuv/main.zig b/src/libuv/main.zig
index d012ab5d3..a3ee6774a 100644
--- a/src/libuv/main.zig
+++ b/src/libuv/main.zig
@@ -1,7 +1,9 @@
 const Loop = @import("Loop.zig");
+const Sem = @import("Sem.zig");
 const Error = @import("error.zig").Error;
 
 test {
     _ = Loop;
+    _ = Sem;
     _ = Error;
 }