zigrtiow: commit example test w/ threads.

zigrtiow/test/threads.zig

@@ -0,0 +1,56 @@
+const std = @import("std");
+const Thread = std.Thread;
+const info = std.log.info;
+const Queue = std.atomic.Queue;
+
+const Task = struct {
+    row_idx: usize,
+    row_pixels: []u8,
+};
+
+fn worker(q: *Queue(Task)) void {
+    while (true) {
+        if (q.get()) |node| {
+            const task = node.data;
+            info("starting thread: {}", .{task.row_idx});
+        } else {
+            return;
+        }
+    }
+}
+
+pub fn main() anyerror!void {
+    const allocator = std.heap.page_allocator;
+    const cpus = try Thread.getCpuCount();
+    const width = 512;
+    const height = 256;
+    var pixels: [width * height * 3]u8 = undefined;
+
+    var threads: std.ArrayList(std.Thread) = std.ArrayList(std.Thread).init(allocator);
+    var q = Queue(Task).init();
+    const Node = Queue(Task).Node;
+    var row: usize = 0;
+    while (row < height) : (row += 1) {
+        const node = try allocator.create(Node);
+        node.* = .{
+            .prev = undefined,
+            .next = undefined,
+            .data = Task{
+                .row_idx = row,
+                .row_pixels = pixels[row * width * 3 .. (row + 1) * width * 3],
+            },
+        };
+        q.put(node);
+    }
+
+    var t: usize = 0;
+    while (t < cpus) : (t += 1) {
+        try threads.append(try Thread.spawn(.{}, worker, .{&q}));
+    }
+
+    // Wait for all threads to finish.
+    for (threads.items) |thread| {
+        Thread.join(thread);
+    }
+    info("main done", .{});
+}