Simplify async function

3 files changed, 88 insertions, 272 deletions

diff --git a/source/kit/async_function.h b/source/kit/async_function.h
index 6bb2e83..6b4616d 100644
--- a/source/kit/async_function.h
+++ b/source/kit/async_function.h
@@ -7,32 +7,16 @@
 extern "C" {
 #endif
 
-enum {
-  KIT_AF_REQUEST_EXECUTE         = 0,
-  KIT_AF_REQUEST_RESUME          = 1,
-  KIT_AF_REQUEST_JOIN            = 2,
-  KIT_AF_REQUEST_RESUME_AND_JOIN = 3
-};
-
 typedef struct {
   int _;
 } kit_af_void;
 
-typedef void (*kit_af_state_machine)(void *self_void_, int request_);
-typedef void (*kit_af_execute)(void *state, void *coro_state,
-                               int request);
+typedef void (*kit_af_state_machine)(void *self_void_);
 
-typedef struct {
-  long long      _internal;
-  void          *state;
-  kit_af_execute execute;
-} kit_af_execution_context;
-
-#define KIT_AF_STATE_DATA                    \
-  struct {                                   \
-    int                      _index;         \
-    kit_af_state_machine     _state_machine; \
-    kit_af_execution_context _context;       \
+#define KIT_AF_STATE_DATA                \
+  struct {                               \
+    int                  _index;         \
+    kit_af_state_machine _state_machine; \
   }
 
 typedef struct {
@@ -41,6 +25,21 @@ typedef struct {
 
 #define KIT_AF_INTERNAL(coro_) (*((kit_af_type_void *) (coro_)))
 
+#ifdef KIT_ENABLE_CUSTOM_ASYNC_FUNCTION_DISPATCH
+/*  Application should implement this function if custom async
+ *  function dispatch is enabled.
+ *
+ *  See KIT_ENABLE_CUSTOM_ASYNC_FUNCTION_DISPATCH macro.
+ */
+void kit_async_function_dispatch(void *promise);
+#else
+static void kit_async_function_dispatch(void *promise) {
+  /*  Dynamic dispatch by default.
+   */
+  KIT_AF_INTERNAL(promise)._state_machine(promise);
+}
+#endif
+
 #define KIT_AF_STATE(ret_type_, name_, ...) \
   struct name_##_coro_state_ {              \
     KIT_AF_STATE_DATA;                      \
@@ -48,22 +47,13 @@ typedef struct {
     __VA_ARGS__                             \
   }
 
-#define KIT_AF_DECL(name_) void name_(void *self_void_, int request_)
-
-#define KIT_CORO_IMPL(name_)                                      \
-  KIT_AF_DECL(name_) {                                            \
-    struct name_##_coro_state_ *self =                            \
-        (struct name_##_coro_state_ *) self_void_;                \
-    if (request_ != KIT_AF_REQUEST_EXECUTE) {                     \
-      if (self->_context.execute != NULL)                         \
-        self->_context.execute(self->_context.state, self_void_,  \
-                               request_);                         \
-      else if (request_ == KIT_AF_REQUEST_JOIN ||                 \
-               request_ == KIT_AF_REQUEST_RESUME_AND_JOIN)        \
-        self->_state_machine(self_void_, KIT_AF_REQUEST_EXECUTE); \
-      return;                                                     \
-    }                                                             \
-    switch (self->_index) {                                       \
+#define KIT_AF_DECL(name_) void name_(void *self_void_)
+
+#define KIT_CORO_IMPL(name_)                       \
+  KIT_AF_DECL(name_) {                             \
+    struct name_##_coro_state_ *self =             \
+        (struct name_##_coro_state_ *) self_void_; \
+    switch (self->_index) {                        \
       case 0:;
 
 #define KIT_AF_LINE_() __LINE__
@@ -94,6 +84,12 @@ typedef struct {
 #define KIT_STATIC_CORO_VOID(name_, ...) \
   KIT_STATIC_CORO(kit_af_void, name_, __VA_ARGS__)
 
+#define KIT_AF_EXECUTE(promise_) \
+  kit_async_function_dispatch(&(promise_))
+
+#define KIT_AF_NEXT(promise_) \
+  (kit_async_function_dispatch(&(promise_)), (promise_).return_value)
+
 #define KIT_AF_YIELD(...)                \
   do {                                   \
     self->_index       = KIT_AF_LINE_(); \
@@ -122,44 +118,40 @@ typedef struct {
     return;                \
   } while (0)
 
-#define KIT_AF_AWAIT(promise_)                                     \
-  do {                                                             \
-    case KIT_AF_LINE_():                                           \
-      if ((promise_)._index != -1) {                               \
-        self->_index = KIT_AF_LINE_();                             \
-        (promise_)._state_machine(&(promise_),                     \
-                                  KIT_AF_REQUEST_RESUME_AND_JOIN); \
-      }                                                            \
-      if ((promise_)._index != -1)                                 \
-        return;                                                    \
+#define KIT_AF_AWAIT(promise_)                    \
+  do {                                            \
+    case KIT_AF_LINE_():                          \
+      if ((promise_)._index != -1) {              \
+        self->_index = KIT_AF_LINE_();            \
+        kit_async_function_dispatch(&(promise_)); \
+      }                                           \
+      if ((promise_)._index != -1)                \
+        return;                                   \
   } while (0)
 
-#define KIT_AF_YIELD_AWAIT(promise_)                               \
-  do {                                                             \
-    case KIT_AF_LINE_():                                           \
-      if ((promise_)._index != -1) {                               \
-        self->_index = KIT_AF_LINE_();                             \
-        (promise_)._state_machine(&(promise_),                     \
-                                  KIT_AF_REQUEST_RESUME_AND_JOIN); \
-        self->return_value = (promise_).return_value;              \
-        return;                                                    \
-      }                                                            \
+#define KIT_AF_YIELD_AWAIT(promise_)                  \
+  do {                                                \
+    case KIT_AF_LINE_():                              \
+      if ((promise_)._index != -1) {                  \
+        self->_index = KIT_AF_LINE_();                \
+        kit_async_function_dispatch(&(promise_));     \
+        self->return_value = (promise_).return_value; \
+        return;                                       \
+      }                                               \
   } while (0)
 
 #define KIT_AF_TYPE(coro_) struct coro_##_coro_state_
 
-#define KIT_AF_INITIAL(coro_)             \
-  ._index = 0, ._state_machine = (coro_), \
-  ._context = { .state = NULL, .execute = NULL }
+#define KIT_AF_INITIAL(coro_) ._index = 0, ._state_machine = (coro_)
 
 #define KIT_AF_CREATE(promise_, coro_, ...) \
   KIT_AF_TYPE(coro_)                        \
   promise_ = { KIT_AF_INITIAL(coro_), __VA_ARGS__ }
 
-#define KIT_AF_INIT(promise_, coro_, ...)            \
-  do {                                               \
-    KIT_AF_CREATE(kit_af_temp_, coro_, __VA_ARGS__); \
-    (promise_) = kit_af_temp_;                       \
+#define KIT_AF_INIT(promise_, coro_, ...)                    \
+  do {                                                       \
+    KIT_AF_CREATE(kit_af_temp_, coro_, __VA_ARGS__);         \
+    memcpy(&(promise_), &kit_af_temp_, sizeof kit_af_temp_); \
   } while (0)
 
 #define KIT_AF_INIT_EXPLICIT(promise_, size_, coro_func_) \
@@ -168,59 +160,6 @@ typedef struct {
     (promise_)._state_machine = (coro_func_);             \
   } while (0)
 
-#define KIT_AF_EXECUTION_CONTEXT(promise_, ...)               \
-  do {                                                        \
-    kit_af_execution_context kit_af_temp_ = { ._internal = 0, \
-                                              __VA_ARGS__ };  \
-    (promise_)._context                   = kit_af_temp_;     \
-  } while (0)
-
-#define KIT_AF_RESUME(promise_) \
-  (promise_)._state_machine(&(promise_), KIT_AF_REQUEST_RESUME)
-
-#define KIT_AF_RESUME_N(promises_, size_)            \
-  do {                                               \
-    int kit_af_index_;                               \
-    for (kit_af_index_ = 0; kit_af_index_ < (size_); \
-         kit_af_index_++)                            \
-      KIT_AF_RESUME((promises_)[kit_af_index_]);     \
-  } while (0)
-
-#define KIT_AF_JOIN(promise_)                                   \
-  ((promise_)._state_machine(&(promise_), KIT_AF_REQUEST_JOIN), \
-   (promise_).return_value)
-
-#define KIT_AF_JOIN_N(promises_, size_)               \
-  do {                                                \
-    int kit_af_index_;                                \
-    for (kit_af_index_ = 0; kit_af_index_ < (size_);  \
-         kit_af_index_++)                             \
-      (void) KIT_AF_JOIN((promises_)[kit_af_index_]); \
-  } while (0)
-
-#define KIT_AF_RESUME_AND_JOIN(promise_)                      \
-  ((promise_)._state_machine(&(promise_),                     \
-                             KIT_AF_REQUEST_RESUME_AND_JOIN), \
-   (promise_).return_value)
-
-#define KIT_AF_RESUME_AND_JOIN_N(promises_, size_) \
-  do {                                             \
-    KIT_AF_RESUME_N((promises_), (size_));         \
-    KIT_AF_JOIN_N((promises_), (size_));           \
-  } while (0)
-
-#define KIT_AF_RESUME_ALL(promises_) \
-  KIT_AF_RESUME_N((promises_),       \
-                  sizeof(promises_) / sizeof((promises_)[0]))
-
-#define KIT_AF_JOIN_ALL(promises_) \
-  KIT_AF_JOIN_N((promises_),       \
-                sizeof(promises_) / sizeof((promises_)[0]))
-
-#define KIT_AF_RESUME_AND_JOIN_ALL(promises_)               \
-  KIT_AF_RESUME_AND_JOIN_N((promises_), sizeof(promises_) / \
-                                            sizeof((promises_)[0]))
-
 #define KIT_AF_FINISHED(promise_) ((promise_)._index == -1)
 
 #define KIT_AF_FINISHED_N(return_, promises_, size_)      \
@@ -239,43 +178,12 @@ typedef struct {
   KIT_AF_FINISHED_N((return_), (promises_),     \
                     sizeof(promises_) / sizeof((promises_)[0]))
 
-#define KIT_AF_AWAIT_N(promises_, size_)                     \
-  do {                                                       \
-    int kit_af_done_;                                        \
-    case KIT_AF_LINE_():                                     \
-      self->_index = KIT_AF_LINE_();                         \
-      KIT_AF_RESUME_AND_JOIN_N((promises_), (size_));        \
-      KIT_AF_FINISHED_N(kit_af_done_, (promises_), (size_)); \
-      if (!kit_af_done_)                                     \
-        return;                                              \
-  } while (0)
-
-#define KIT_AF_AWAIT_ALL(promises_) \
-  KIT_AF_AWAIT_N((promises_),       \
-                 sizeof(promises_) / sizeof((promises_)[0]))
-
-#define KIT_AF_EXECUTE(promise_)                       \
-  KIT_AF_INTERNAL(promise_)._state_machine((promise_), \
-                                           KIT_AF_REQUEST_EXECUTE)
-
 #ifndef KIT_DISABLE_SHORT_NAMES
-#  ifndef KIT_DISABLE_AF_SELF_SHORTCUT
-#    define af self->
-#  endif
-
-#  define af_request kit_af_request
-#  define AF_REQUEST_EXECUTE KIT_AF_REQUEST_EXECUTE
-#  define AF_REQUEST_RESUME KIT_AF_REQUEST_RESUME
-#  define AF_REQUEST_JOIN KIT_AF_REQUEST_JOIN
-#  define AF_REQUEST_RESUME_AND_JOIN KIT_AF_REQUEST_RESUME_AND_JOIN
 #  define af_void kit_af_void
 #  define af_state_machine kit_af_state_machine
-#  define af_execute kit_af_execute
-#  define af_execution_context kit_af_execution_context
 #  define af_type_void kit_af_type_void
 
 #  define AF_STATE_DATA KIT_AF_STATE_DATA
-#  define AF_INTERNAL KIT_AF_INTERNAL
 #  define AF_STATE KIT_AF_STATE
 #  define AF_DECL KIT_AF_DECL
 #  define CORO_IMPL KIT_CORO_IMPL
@@ -286,6 +194,8 @@ typedef struct {
 #  define STATIC_CORO KIT_STATIC_CORO
 #  define STATIC_CORO_VOID KIT_STATIC_CORO_VOID
 #  define CORO_VOID KIT_CORO_VOID
+#  define AF_EXECUTE KIT_AF_EXECUTE
+#  define AF_NEXT KIT_AF_NEXT
 #  define AF_YIELD KIT_AF_YIELD
 #  define AF_YIELD_VOID KIT_AF_YIELD_VOID
 #  define AF_RETURN KIT_AF_RETURN
@@ -297,22 +207,9 @@ typedef struct {
 #  define AF_CREATE KIT_AF_CREATE
 #  define AF_INIT KIT_AF_INIT
 #  define AF_INIT_EXPLICIT KIT_AF_INIT_EXPLICIT
-#  define AF_EXECUTION_CONTEXT KIT_AF_EXECUTION_CONTEXT
-#  define AF_RESUME KIT_AF_RESUME
-#  define AF_RESUME_N KIT_AF_RESUME_N
-#  define AF_JOIN KIT_AF_JOIN
-#  define AF_JOIN_N KIT_AF_JOIN_N
-#  define AF_RESUME_AND_JOIN KIT_AF_RESUME_AND_JOIN
-#  define AF_RESUME_AND_JOIN_N KIT_AF_RESUME_AND_JOIN_N
-#  define AF_RESUME_ALL KIT_AF_RESUME_ALL
-#  define AF_JOIN_ALL KIT_AF_JOIN_ALL
-#  define AF_RESUME_AND_JOIN_ALL KIT_AF_RESUME_AND_JOIN_ALL
 #  define AF_FINISHED KIT_AF_FINISHED
 #  define AF_FINISHED_N KIT_AF_FINISHED_N
 #  define AF_FINISHED_ALL KIT_AF_FINISHED_ALL
-#  define AF_AWAIT_N KIT_AF_AWAIT_N
-#  define AF_AWAIT_ALL KIT_AF_AWAIT_ALL
-#  define AF_EXECUTE KIT_AF_EXECUTE
 #endif
 
 #ifdef __cplusplus
diff --git a/source/kit/dynamic_array.c b/source/kit/dynamic_array.c
index d3eaf29..aece99e 100644
--- a/source/kit/dynamic_array.c
+++ b/source/kit/dynamic_array.c
@@ -8,7 +8,6 @@ void kit_da_init(kit_da_void_t *array, ptrdiff_t element_size,
   assert(array != NULL);
   assert(element_size > 0);
   assert(size >= 0);
-  assert(alloc.allocate != NULL);
 
   memset(array, 0, sizeof(kit_da_void_t));
 
@@ -44,8 +43,6 @@ void kit_da_resize(kit_da_void_t *array, ptrdiff_t element_size,
   } else {
     ptrdiff_t capacity = eval_capacity(array->capacity, size);
 
-    assert(array->alloc.allocate != NULL);
-
     void *bytes = kit_alloc_dispatch(
         array->alloc, KIT_ALLOCATE, element_size * capacity, 0, NULL);
 
diff --git a/source/test/unittests/async_function.test.c b/source/test/unittests/async_function.test.c
index 5adc0e7..a10dbff 100644
--- a/source/test/unittests/async_function.test.c
+++ b/source/test/unittests/async_function.test.c
@@ -21,8 +21,9 @@ CORO_IMPL(test_bar) {
 CORO_END
 
 STATIC_CORO(int, test_gen, int i; int min; int max;) {
-  for (af i = af min; af i < af max; af i++) AF_YIELD(af i);
-  AF_RETURN(af max);
+  for (self->i = self->min; self->i < self->max; self->i++)
+    AF_YIELD(self->i);
+  AF_RETURN(self->max);
 }
 CORO_END
 
@@ -34,54 +35,19 @@ STATIC_CORO_VOID(test_task, ) {
 CORO_END
 
 STATIC_CORO_VOID(test_nest_task, AF_TYPE(test_task) promise;) {
-  AF_INIT(af promise, test_task, );
-  AF_AWAIT(af promise);
-  AF_AWAIT(af promise);
-  AF_AWAIT(af promise);
+  AF_INIT(self->promise, test_task, );
+  AF_AWAIT(self->promise);
+  AF_AWAIT(self->promise);
+  AF_AWAIT(self->promise);
 }
 CORO_END
 
 STATIC_CORO(int, test_nest_generator, AF_TYPE(test_gen) promise;) {
-  AF_INIT(af promise, test_gen, .min = 1, .max = 3);
-  AF_YIELD_AWAIT(af promise);
+  AF_INIT(self->promise, test_gen, .min = 1, .max = 3);
+  AF_YIELD_AWAIT(self->promise);
 }
 CORO_END
 
-STATIC_CORO(int, test_join_multiple, AF_TYPE(test_bar) promises[3];) {
-  int i;
-  for (i = 0; i < 3; i++)
-    AF_INIT(af promises[i], test_bar, .return_value = 0);
-  AF_RESUME_AND_JOIN_ALL(af promises);
-  AF_RETURN(af promises[0].return_value +
-            af promises[1].return_value +
-            af promises[2].return_value);
-}
-CORO_END
-
-STATIC_CORO(int, test_await_multiple,
-            AF_TYPE(test_bar) promises[3];) {
-  int i;
-  for (i = 0; i < 3; i++)
-    AF_INIT(af promises[i], test_bar, .return_value = 0);
-  AF_AWAIT_ALL(af promises);
-  AF_RETURN(af promises[0].return_value +
-            af promises[1].return_value +
-            af promises[2].return_value);
-}
-CORO_END
-
-void test_execute_lazy(void *_, void *coro, int request) {
-  if (request == AF_REQUEST_RESUME)
-    return;
-  AF_EXECUTE(coro);
-}
-
-void test_execute_immediate(void *_, void *coro, int request) {
-  if (request == AF_REQUEST_JOIN)
-    return;
-  AF_EXECUTE(coro);
-}
-
 TEST("coroutine create") {
   AF_CREATE(promise, test_foo, );
   REQUIRE(!AF_FINISHED(promise));
@@ -106,111 +72,67 @@ TEST("coroutine init with value") {
   REQUIRE(!AF_FINISHED(promise));
 }
 
-TEST("coroutine resume") {
+TEST("coroutine create with value") {
   AF_CREATE(promise, test_foo, .return_value = -1);
-  AF_RESUME(promise);
   REQUIRE(promise.return_value == -1);
   REQUIRE(!AF_FINISHED(promise));
 }
 
-TEST("coroutine resume and join") {
+TEST("coroutine execute and return") {
   AF_CREATE(promise, test_foo, );
-  REQUIRE(AF_RESUME_AND_JOIN(promise) == 42);
+  REQUIRE(AF_NEXT(promise) == 42);
   REQUIRE(AF_FINISHED(promise));
 }
 
-TEST("coroutine resume and join manually") {
-  AF_CREATE(promise, test_foo, );
-  AF_RESUME(promise);
-  REQUIRE(AF_JOIN(promise) == 42);
-  REQUIRE(AF_FINISHED(promise));
-}
-
-TEST("coroutine suspend") {
+TEST("coroutine execute two steps") {
   AF_CREATE(promise, test_bar, .return_value = 0);
-  REQUIRE(AF_RESUME_AND_JOIN(promise) == 0);
-  REQUIRE(AF_RESUME_AND_JOIN(promise) == 42);
+  AF_EXECUTE(promise);
+  REQUIRE(promise.return_value == 0);
+  AF_EXECUTE(promise);
+  REQUIRE(promise.return_value == 42);
 }
 
 TEST("coroutine generator") {
   int i;
   AF_CREATE(promise, test_gen, .min = 10, .max = 15);
-  for (i = 0; i <= 5; i++)
-    REQUIRE(AF_RESUME_AND_JOIN(promise) == 10 + i);
+  for (i = 0; i <= 5; i++) REQUIRE(AF_NEXT(promise) == 10 + i);
 }
 
 TEST("coroutine status finished") {
   AF_CREATE(promise, test_bar, );
   REQUIRE(!AF_FINISHED(promise));
-  (void) AF_RESUME_AND_JOIN(promise);
+  AF_EXECUTE(promise);
   REQUIRE(!AF_FINISHED(promise));
-  (void) AF_RESUME_AND_JOIN(promise);
+  AF_EXECUTE(promise);
   REQUIRE(AF_FINISHED(promise));
 }
 
 TEST("coroutine task") {
   AF_CREATE(promise, test_task, );
-  (void) AF_RESUME_AND_JOIN(promise);
+  AF_EXECUTE(promise);
   REQUIRE(!AF_FINISHED(promise));
-  (void) AF_RESUME_AND_JOIN(promise);
+  AF_EXECUTE(promise);
   REQUIRE(!AF_FINISHED(promise));
-  (void) AF_RESUME_AND_JOIN(promise);
+  AF_EXECUTE(promise);
   REQUIRE(AF_FINISHED(promise));
 }
 
 TEST("coroutine nested task") {
   AF_CREATE(promise, test_nest_task, );
-  (void) AF_RESUME_AND_JOIN(promise);
+  AF_EXECUTE(promise);
   REQUIRE(!AF_FINISHED(promise));
-  (void) AF_RESUME_AND_JOIN(promise);
+  AF_EXECUTE(promise);
   REQUIRE(!AF_FINISHED(promise));
-  (void) AF_RESUME_AND_JOIN(promise);
+  AF_EXECUTE(promise);
   REQUIRE(AF_FINISHED(promise));
 }
 
 TEST("coroutine nested generator") {
   AF_CREATE(promise, test_nest_generator, );
-  REQUIRE(AF_RESUME_AND_JOIN(promise) == 1);
-  REQUIRE(AF_RESUME_AND_JOIN(promise) == 2);
-  REQUIRE(AF_RESUME_AND_JOIN(promise) == 3);
+  REQUIRE(AF_NEXT(promise) == 1);
+  REQUIRE(AF_NEXT(promise) == 2);
+  REQUIRE(AF_NEXT(promise) == 3);
   REQUIRE(!AF_FINISHED(promise));
-  (void) AF_RESUME_AND_JOIN(promise);
-  REQUIRE(AF_FINISHED(promise));
-}
-
-TEST("coroutine join multiple") {
-  AF_CREATE(promise, test_join_multiple, );
-  REQUIRE(AF_RESUME_AND_JOIN(promise) == 0);
-  REQUIRE(AF_FINISHED(promise));
-}
-
-TEST("coroutine await multiple") {
-  AF_CREATE(promise, test_await_multiple, );
-  REQUIRE(AF_RESUME_AND_JOIN(promise) == 0);
-  REQUIRE(AF_RESUME_AND_JOIN(promise) == 42 * 3);
-  REQUIRE(AF_FINISHED(promise));
-}
-
-TEST("coroutine custom execution context lazy") {
-  AF_CREATE(promise, test_foo, .return_value = 0);
-  AF_EXECUTION_CONTEXT(promise, .state = NULL,
-                       .execute = test_execute_lazy);
-  AF_RESUME(promise);
-  REQUIRE(promise.return_value == 0);
-  REQUIRE(!AF_FINISHED(promise));
-  (void) AF_JOIN(promise);
-  REQUIRE(promise.return_value == 42);
-  REQUIRE(AF_FINISHED(promise));
-}
-
-TEST("coroutine custom execution context immediate") {
-  AF_CREATE(promise, test_foo, .return_value = 0);
-  AF_EXECUTION_CONTEXT(promise, .state = NULL,
-                       .execute = test_execute_immediate);
-  AF_RESUME(promise);
-  REQUIRE(promise.return_value == 42);
-  REQUIRE(AF_FINISHED(promise));
-  (void) AF_JOIN(promise);
-  REQUIRE(promise.return_value == 42);
+  AF_EXECUTE(promise);
   REQUIRE(AF_FINISHED(promise));
 }