Support Host function invocation

kateinoigakukun · kateinoigakukun · commit d58b94f4f38f · 2020-03-05T11:57:40.000+09:00
diff --git a/src/swift/Makefile b/src/swift/Makefile
@@ -7,7 +7,9 @@ build: .wasi-sdk/dummy
 		-Xswiftc -Xclang-linker \
 		-Xswiftc --sysroot=$(WASI_SDK_DIR)/share/wasi-sysroot \
 		-Xcc --sysroot=$(WASI_SDK_DIR)/share/wasi-sysroot \
-		-Xlinker --allow-undefined
+		-Xlinker --allow-undefined \
+		-Xlinker --export=swjs_call_host_function \
+		-Xlinker --export=swjs_prepare_host_function_call
 .wasi-sdk/dummy:
 	./script/install-wasi-sdk.sh $(WASI_SDK_DIR)
 	touch .wasi-sdk/dummy
diff --git a/src/swift/Sources/JavaScriptKit/JSFunction.swift b/src/swift/Sources/JavaScriptKit/JSFunction.swift
@@ -27,4 +27,35 @@ public class JSFunctionRef: Equatable {
         }
         return result.jsValue()
     }
+
+    static var sharedFunctions: [([JSValue]) -> JSValue] = []
+    public static func from(_ body: @escaping ([JSValue]) -> JSValue) -> JSFunctionRef {
+        let id = JavaScriptHostFuncRef(sharedFunctions.count)
+        sharedFunctions.append(body)
+        var funcRef: JavaScriptObjectRef = 0
+        _create_function(id, &funcRef)
+
+        return JSFunctionRef(id: funcRef)
+    }
+}
+
+
+@_cdecl("swjs_prepare_host_function_call")
+public func _prepare_host_function_call(_ argc: Int32) -> UnsafeMutableRawPointer {
+    let argumentSize = MemoryLayout<RawJSValue>.size * Int(argc)
+    return malloc(Int(argumentSize))!
+}
+
+@_cdecl("swjs_call_host_function")
+public func _call_host_function(
+    _ hostFuncRef: JavaScriptHostFuncRef,
+    _ argv: UnsafePointer<RawJSValue>, _ argc: Int32,
+    _ callbackFuncRef: JavaScriptPayload) {
+    let hostFunc = JSFunctionRef.sharedFunctions[Int(hostFuncRef)]
+    let args = UnsafeBufferPointer(start: argv, count: Int(argc)).map {
+        $0.jsValue()
+    }
+    let result = hostFunc(args)
+    let callbackFuncRef = JSFunctionRef(id: callbackFuncRef)
+    _ = callbackFuncRef(result)
 }
diff --git a/src/swift/Sources/JavaScriptKit/JSValueConvertible.swift b/src/swift/Sources/JavaScriptKit/JSValueConvertible.swift
@@ -23,7 +23,7 @@ extension RawJSValue: JSValueConvertible {
             // +1 for null terminator
             let buffer = malloc(Int(payload2 + 1))!.assumingMemoryBound(to: UInt8.self)
             defer { free(buffer) }
-            _load_string(payload1 as JavaScriptValueId, buffer)
+            _load_string(payload1 as JavaScriptObjectRef, buffer)
             buffer[Int(payload2)] = 0
             let string = String(decodingCString: UnsafePointer(buffer), as: UTF8.self)
             return .string(string)
diff --git a/src/swift/Sources/JavaScriptKit/XcodeSupport.swift b/src/swift/Sources/JavaScriptKit/XcodeSupport.swift
@@ -7,36 +7,37 @@ import _CJavaScriptKit
 /// When running with JavaScript runtime library, they are ignored completely.
 #if Xcode
 func _set_prop(
-    _ _this: JavaScriptValueId,
+    _ _this: JavaScriptObjectRef,
     _ prop: UnsafePointer<Int8>!, _ length: Int32,
     _ kind: JavaScriptValueKind,
     _ payload1: JavaScriptPayload,
     _ payload2: JavaScriptPayload) { fatalError() }
 func _get_prop(
-    _ _this: JavaScriptValueId,
+    _ _this: JavaScriptObjectRef,
     _ prop: UnsafePointer<Int8>!, _ length: Int32,
     _ kind: UnsafeMutablePointer<JavaScriptValueKind>!,
     _ payload1: UnsafeMutablePointer<JavaScriptPayload>!,
     _ payload2: UnsafeMutablePointer<JavaScriptPayload>!) { fatalError() }
 func _set_subscript(
-    _ _this: JavaScriptValueId,
+    _ _this: JavaScriptObjectRef,
     _ index: Int32,
     _ kind: JavaScriptValueKind,
     _ payload1: JavaScriptPayload,
     _ payload2: JavaScriptPayload) { fatalError() }
 func _get_subscript(
-    _ _this: JavaScriptValueId,
+    _ _this: JavaScriptObjectRef,
     _ index: Int32,
     _ kind: UnsafeMutablePointer<JavaScriptValueKind>!,
     _ payload1: UnsafeMutablePointer<JavaScriptPayload>!,
     _ payload2: UnsafeMutablePointer<JavaScriptPayload>!) { fatalError() }
 func _load_string(
-    _ ref: JavaScriptValueId,
+    _ ref: JavaScriptObjectRef,
     _ buffer: UnsafeMutablePointer<UInt8>!) { fatalError() }
 func _call_function(
-    _ ref: JavaScriptValueId,
-    _ args: UnsafePointer<RawJSValue>!, _ length: Int32,
+    _ ref: JavaScriptObjectRef,
+    _ argv: UnsafePointer<RawJSValue>!, _ argc: Int32,
     _ result_kind: UnsafeMutablePointer<JavaScriptValueKind>!,
     _ result_payload1: UnsafeMutablePointer<JavaScriptPayload>!,
     _ result_payload2: UnsafeMutablePointer<JavaScriptPayload>!) { fatalError() }
+func _create_function(_ host_func_id: JavaScriptHostFuncRef, _ func_ref_ptr: UnsafePointer<JavaScriptObjectRef>!) {}
 #endif
diff --git a/src/swift/Sources/_CJavaScriptKit/include/_CJavaScriptKit.h b/src/swift/Sources/_CJavaScriptKit/include/_CJavaScriptKit.h
@@ -3,7 +3,8 @@
 
 #include <stdlib.h>
 
-typedef unsigned int JavaScriptValueId;
+typedef unsigned int JavaScriptObjectRef;
+typedef unsigned int JavaScriptHostFuncRef;
 
 typedef enum {
     JavaScriptValueKind_Invalid   = -1,
@@ -32,7 +33,7 @@ __attribute__((
     __import_name__("swjs_set_prop")
 ))
 extern void _set_prop(
-    const JavaScriptValueId _this,
+    const JavaScriptObjectRef _this,
     const char *prop,
     const int length,
     const JavaScriptValueKind kind,
@@ -45,7 +46,7 @@ __attribute__((
     __import_name__("swjs_get_prop")
 ))
 extern void _get_prop(
-    const JavaScriptValueId _this,
+    const JavaScriptObjectRef _this,
     const char *prop,
     const int length,
     JavaScriptValueKind *kind,
@@ -58,7 +59,7 @@ __attribute__((
     __import_name__("swjs_set_subscript")
 ))
 extern void _set_subscript(
-    const JavaScriptValueId _this,
+    const JavaScriptObjectRef _this,
     const int length,
     const JavaScriptValueKind kind,
     const JavaScriptPayload payload1,
@@ -70,7 +71,7 @@ __attribute__((
     __import_name__("swjs_get_subscript")
 ))
 extern void _get_subscript(
-    const JavaScriptValueId _this,
+    const JavaScriptObjectRef _this,
     const int length,
     JavaScriptValueKind *kind,
     JavaScriptPayload *payload1,
@@ -82,7 +83,7 @@ __attribute__((
     __import_name__("swjs_load_string")
 ))
 extern void _load_string(
-    const JavaScriptValueId ref,
+    const JavaScriptObjectRef ref,
     unsigned char *buffer
 );
 
@@ -91,11 +92,20 @@ __attribute__((
     __import_name__("swjs_call_function")
 ))
 extern void _call_function(
-    const JavaScriptValueId ref,
-    const RawJSValue *args, const int length,
+    const JavaScriptObjectRef ref,
+    const RawJSValue *argv, const int argc,
     JavaScriptValueKind *result_kind,
     JavaScriptPayload *result_payload1,
     JavaScriptPayload *result_payload2
 );
 
+__attribute__((
+    __import_module__("javascript_kit"),
+    __import_name__("swjs_create_function")
+))
+extern void _create_function(
+    const JavaScriptHostFuncRef host_func_id,
+    const JavaScriptObjectRef *func_ref_ptr
+);
+
 #endif /* _CJavaScriptKit_h */
diff --git a/src/web/src/index.ts b/src/web/src/index.ts
@@ -9,6 +9,14 @@ interface GlobalVariable { }
 declare const window: GlobalVariable;
 declare const global: GlobalVariable;
 
+interface SwiftRuntimeExportedFunctions {
+    swjs_prepare_host_function_call(size: number): pointer;
+    swjs_call_host_function(
+        host_func_id: number,
+        argv: pointer, argc: number,
+        callback_func_ref: ref
+    ): void;
+}
 
 enum JavaScriptValueKind {
     Invalid = -1,
@@ -56,6 +64,28 @@ export class SwiftRuntime {
             return id
         }
 
+        const callHostFunction = (host_func_id: number, args: any[]) => {
+            if (!this.instance)
+                throw new Error("WebAssembly instance is not set yet");
+            const exports = this.instance.exports as any as SwiftRuntimeExportedFunctions;
+            const argc = args.length
+            const argv = exports.swjs_prepare_host_function_call(argc)
+            for (let index = 0; index < args.length; index++) {
+                const argument = args[index]
+                const value = encodeValue(argument)
+                const base = argv + 12 * index
+                writeUint32(base, value.kind)
+                writeUint32(base + 4, value.payload1)
+                writeUint32(base + 8, value.payload2)
+            }
+            let output: any;
+            const callback_func_ref = allocValue(function(result: any) {
+                output = result
+            })
+            exports.swjs_call_host_function(host_func_id, argv, argc, callback_func_ref)
+            return output
+        }
+
         const textDecoder = new TextDecoder('utf-8');
         const textEncoder = new TextEncoder(); // Only support utf-8
 
@@ -250,7 +280,16 @@ export class SwiftRuntime {
                 writeUint32(kind_ptr, kind);
                 writeUint32(payload1_ptr, payload1);
                 writeUint32(payload2_ptr, payload2);
-            }
+            },
+            swjs_create_function: (
+                host_func_id: number,
+                func_ref_ptr: pointer,
+            ) => {
+                const func_ref = allocValue(function() {
+                    return callHostFunction(host_func_id, Array.prototype.slice.call(arguments))
+                })
+                writeUint32(func_ref_ptr, func_ref)
+            },
         }
     }
 }
diff --git a/test/JavaScriptKitExec/Sources/JavaScriptKitExec/UnitTestUtils.swift b/test/JavaScriptKitExec/Sources/JavaScriptKitExec/UnitTestUtils.swift
@@ -44,3 +44,11 @@ func expectNumber(_ value: JSValue) throws -> Int32 {
         throw MessageError("Type of \(value) should be \"number\"")
     }
 }
+
+func expectString(_ value: JSValue) throws -> String {
+    switch value {
+    case .string(let string): return string
+    default:
+        throw MessageError("Type of \(value) should be \"string\"")
+    }
+}
diff --git a/test/JavaScriptKitExec/Sources/JavaScriptKitExec/main.swift b/test/JavaScriptKitExec/Sources/JavaScriptKitExec/main.swift
@@ -80,6 +80,7 @@ Function_Call: do {
     //       if (c) { return a } else { return b }
     //     },
     //   }
+    //   ...
     // }
     // ```
     //
@@ -109,3 +110,48 @@ Function_Call: do {
 } catch {
     print(error)
 }
+
+Host_Function_Registration: do {
+
+    // ```js
+    // global.globalObject1 = {
+    //   ...
+    //   "prop_6": {
+    //     "call_host_1": function() {
+    //       return global.globalObject1.prop_6.host_func_1()
+    //     }
+    //   }
+    // }
+    // ```
+    let globalObject1 = getJSValue(this: .global(), name: "globalObject1")
+    let globalObject1Ref = try expectObject(globalObject1)
+    let prop_6 = getJSValue(this: globalObject1Ref, name: "prop_6")
+    let prop_6Ref = try expectObject(prop_6)
+
+    var isHostFunc1Called = false
+    let hostFunc1 = JSFunctionRef.from { (arguments) -> JSValue in
+        isHostFunc1Called = true
+        return .number(1)
+    }
+
+    setJSValue(this: prop_6Ref, name: "host_func_1", value: .function(hostFunc1))
+
+    let call_host_1 = getJSValue(this: prop_6Ref, name: "call_host_1")
+    let call_host_1Func = try expectFunction(call_host_1)
+    try expectEqual(call_host_1Func(), .number(1))
+    try expectEqual(isHostFunc1Called, true)
+
+    let hostFunc2 = JSFunctionRef.from { (arguments) -> JSValue in
+        do {
+            let input = try expectNumber(arguments[0])
+            return .number(input * 2)
+        } catch {
+            return .string(String(describing: error))
+        }
+    }
+
+    try expectEqual(hostFunc2(.number(3)), .number(6))
+    _ = try expectString(hostFunc2(.boolean(true)))
+} catch {
+    print(error)
+}
diff --git a/test/index.js b/test/index.js
@@ -36,6 +36,11 @@ global.globalObject1 = {
     "func6": function (c, a, b) {
       if (c) { return a } else { return b }
     },
+  },
+  "prop_6": {
+    "call_host_1": () => {
+      return global.globalObject1.prop_6.host_func_1()
+    }
   }
 }
 

Original file line number	Diff line number	Diff line change
`@@ -44,3 +44,11 @@ func expectNumber(_ value: JSValue) throws -> Int32 {`
`44`	`44`	`throw MessageError("Type of \(value) should be \"number\"")`
`45`	`45`	`}`
`46`	`46`	`}`
	`47`	`+`
	`48`	`+func expectString(_ value: JSValue) throws -> String {`
	`49`	`+ switch value {`
	`50`	`+ case .string(let string): return string`
	`51`	`+ default:`
	`52`	`+ throw MessageError("Type of \(value) should be \"string\"")`
	`53`	`+ }`
	`54`	`+}`
Original file line number	Diff line number	Diff line change
`@@ -36,6 +36,11 @@ global.globalObject1 = {`
`36`	`36`	`"func6": function (c, a, b) {`
`37`	`37`	`if (c) { return a } else { return b }`
`38`	`38`	`},`
	`39`	`+ },`
	`40`	`+ "prop_6": {`
	`41`	`+ "call_host_1": () => {`
	`42`	`+ return global.globalObject1.prop_6.host_func_1()`
	`43`	`+ }`
`39`	`44`	`}`
`40`	`45`	`}`
`41`	`46`