gpu: implement ShaderModule.getCompilationInfo

Signed-off-by: Stephen Gutekanst <stephen@hexops.com>

gpu/src/ShaderModule.zig

@@ -8,23 +8,75 @@ vtable: *const VTable,
 pub const VTable = struct {
     reference: fn (ptr: *anyopaque) void,
     release: fn (ptr: *anyopaque) void,
-    // TODO:
-    // WGPU_EXPORT void wgpuShaderModuleGetCompilationInfo(WGPUShaderModule shaderModule, WGPUCompilationInfoCallback callback, void * userdata);
     setLabel: fn (ptr: *anyopaque, label: [:0]const u8) void,
+    getCompilationInfo: fn (ptr: *anyopaque, callback: *CompilationInfoCallback) void,
 };
 
-pub inline fn reference(queue: ShaderModule) void {
-    queue.vtable.reference(queue.ptr);
+pub inline fn reference(shader: ShaderModule) void {
+    shader.vtable.reference(shader.ptr);
 }
 
-pub inline fn release(queue: ShaderModule) void {
-    queue.vtable.release(queue.ptr);
+pub inline fn release(shader: ShaderModule) void {
+    shader.vtable.release(shader.ptr);
 }
 
-pub inline fn setLabel(queue: ShaderModule, label: [:0]const u8) void {
-    queue.vtable.setLabel(queue.ptr, label);
+pub inline fn setLabel(shader: ShaderModule, label: [:0]const u8) void {
+    shader.vtable.setLabel(shader.ptr, label);
 }
 
+pub inline fn getCompilationInfo(shader: ShaderModule, callback: *CompilationInfoCallback) void {
+    shader.vtable.getCompilationInfo(shader.ptr, callback);
+}
+
+pub const CompilationInfoCallback = struct {
+    type_erased_ctx: *anyopaque,
+    type_erased_callback: fn (ctx: *anyopaque, status: CompilationInfoRequestStatus, info: *const CompilationInfo) callconv(.Inline) void,
+
+    pub fn init(
+        comptime Context: type,
+        ctx: *Context,
+        comptime callback: fn (ctx: *Context, status: CompilationInfoRequestStatus, info: *const CompilationInfo) void,
+    ) CompilationInfoCallback {
+        const erased = (struct {
+            pub inline fn erased(type_erased_ctx: *anyopaque, status: CompilationInfoRequestStatus) void {
+                callback(@ptrCast(*Context, @alignCast(@alignOf(*Context), type_erased_ctx)), status);
+            }
+        }).erased;
+
+        return .{
+            .type_erased_ctx = ctx,
+            .type_erased_callback = erased,
+        };
+    }
+};
+
+pub const CompilationInfoRequestStatus = enum(u32) {
+    success = 0x00000000,
+    err = 0x00000001,
+    device_lost = 0x00000002,
+    unknown = 0x00000003,
+};
+
+pub const CompilationInfo = struct {
+    messages: []const CompilationMessage,
+};
+
+pub const CompilationMessageType = enum(u32) {
+    err = 0x00000000,
+    warning = 0x00000001,
+    info = 0x00000002,
+};
+
+pub const CompilationMessage = extern struct {
+    reserved: ?*anyopaque = null,
+    message: [*:0]const u8,
+    type: CompilationMessageType,
+    line_num: u64,
+    line_pos: u64,
+    offset: u64,
+    length: u64,
+};
+
 pub const CodeTag = enum {
     spirv,
     wgsl,
@@ -42,6 +94,10 @@ test "syntax" {
     _ = VTable;
     _ = reference;
     _ = release;
+    _ = CompilationInfoRequestStatus;
+    _ = CompilationInfo;
+    _ = CompilationMessageType;
+    _ = CompilationMessage;
     _ = CodeTag;
     _ = Descriptor;
 }