1 files changed, 109 insertions, 0 deletions
diff --git a/riverctl/main.zig b/riverctl/main.zig
new file mode 100644
index 0000000..287c1aa
--- /dev/null
+++ b/riverctl/main.zig
@@ -0,0 +1,109 @@
+// This file is part of river, a dynamic tiling wayland compositor.
+//
+// Copyright 2020 Isaac Freund
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program. If not, see <https://www.gnu.org/licenses/>.
+
+const std = @import("std");
+
+const c = @cImport({
+    @cInclude("wayland-client.h");
+    @cInclude("river-control-unstable-v1-client-protocol.h");
+});
+
+const wl_registry_listener = c.wl_registry_listener{
+    .global = handleGlobal,
+    .global_remove = handleGlobalRemove,
+};
+
+const command_callback_listener = c.zriver_command_callback_v1_listener{
+    .success = handleSuccess,
+    .failure = handleFailure,
+};
+
+var river_control_optional: ?*c.zriver_control_v1 = null;
+
+pub fn main() !void {
+    const wl_display = c.wl_display_connect(null) orelse return error.CantConnectToDisplay;
+    const wl_registry = c.wl_display_get_registry(wl_display);
+
+    if (c.wl_registry_add_listener(wl_registry, &wl_registry_listener, null) < 0)
+        return error.FailedToAddListener;
+    if (c.wl_display_roundtrip(wl_display) < 0) return error.RoundtripFailed;
+
+    const river_control = river_control_optional orelse return error.RiverControlNotAdvertised;
+
+    var command: c.wl_array = undefined;
+    c.wl_array_init(&command);
+    var it = std.process.args();
+    // Skip our name
+    _ = it.nextPosix();
+    while (it.nextPosix()) |arg| {
+        // Add one as we need to copy the null terminators as well
+        var ptr = @ptrCast([*]u8, c.wl_array_add(&command, arg.len + 1) orelse
+            return error.OutOfMemory);
+        for (arg) |ch, i| ptr[i] = ch;
+        ptr[arg.len] = 0;
+    }
+
+    const command_callback = c.zriver_control_v1_run_command(river_control, &command);
+    if (c.zriver_command_callback_v1_add_listener(
+        command_callback,
+        &command_callback_listener,
+        null,
+    ) < 0) return error.FailedToAddListener;
+
+    // Loop until our callback is called and we exit.
+    while (true) if (c.wl_display_dispatch(wl_display) < 0) return error.DispatchFailed;
+}
+
+fn handleGlobal(
+    data: ?*c_void,
+    wl_registry: ?*c.wl_registry,
+    name: u32,
+    interface: ?[*:0]const u8,
+    version: u32,
+) callconv(.C) void {
+    // We only care about the river_control global
+    if (std.mem.eql(
+        u8,
+        std.mem.spanZ(interface.?),
+        std.mem.spanZ(@ptrCast([*:0]const u8, c.zriver_control_v1_interface.name.?)),
+    )) {
+        river_control_optional = @ptrCast(
+            *c.zriver_control_v1,
+            c.wl_registry_bind(wl_registry, name, &c.zriver_control_v1_interface, 1),
+        );
+    }
+}
+
+/// Ignore the event
+fn handleGlobalRemove(data: ?*c_void, wl_registry: ?*c.wl_registry, name: u32) callconv(.C) void {}
+
+/// On success we simply exit with a clean exit code
+fn handleSuccess(data: ?*c_void, callback: ?*c.zriver_command_callback_v1) callconv(.C) void {
+    std.os.exit(0);
+}
+
+/// Print the failure message and exit non-zero
+fn handleFailure(
+    data: ?*c_void,
+    callback: ?*c.zriver_command_callback_v1,
+    failure_message: ?[*:0]const u8,
+) callconv(.C) void {
+    if (failure_message) |message| {
+        std.debug.warn("Error: {}\n", .{failure_message});
+    }
+    std.os.exit(1);
+}