add boost_fcontext backend

Same as fcontext, but links to the Boost.Context library for the
fcontext asm routines. Requires a C++ compiler.

include/koishi.h

@@ -70,6 +70,11 @@
 			#define offsetof(type, field) ((size_t)&(((type *)0)->field))
 		#endif
 	#endif
+
+	#ifdef __cplusplus
+		#undef KOISHI_THREAD_LOCAL
+		#define KOISHI_THREAD_LOCAL thread_local
+	#endif
 #endif
 
 #ifdef __cplusplus
@@ -223,7 +228,7 @@ KOISHI_API void *koishi_yield(void *arg);
  *
  * @param arg Value to return from the corresponding #koishi_resume call.
  */
-KOISHI_API KOISHI_NORETURN void koishi_die(void *arg);
+KOISHI_NORETURN KOISHI_API void koishi_die(void *arg);
 
 /**
  * @brief Stop a coroutine.

meson_options.txt

@@ -4,6 +4,7 @@ option(
     choices : [
         'auto',
         'fcontext',
+        'boost_fcontext',
         'win32fiber',
         'emscripten',
         'ucontext_e2k',

src/emscripten/meson.build

@@ -17,6 +17,7 @@ else
 endif
 
 emscripten_src = files('emscripten.c')
+emscripten_deps = []
 emscripten_args = []
 emscripten_external_args = []
 emscripten_external_link_args = emscripten_asyncify_args

src/fcontext/fcontext.c

@@ -3,19 +3,18 @@
 #include <stdint.h>
 #include <stdlib.h>
 #include <assert.h>
-#include "../stack_alloc.h"
-
-typedef struct fcontext *fcontext_t;
 
-typedef struct fcontext_fiber {
-	fcontext_t fctx;
-	char *stack;
-	size_t stack_size;
-	KOISHI_VALGRIND_STACK_ID(valgrind_stack_id)
-} koishi_fiber_t;
+#ifdef __cplusplus
+extern "C" {
+#endif
+#include "../stack_alloc.h"
+#ifdef __cplusplus
+}
+#endif
 
-#include "../fiber.h"
+#ifndef USE_BOOST_FCONTEXT
 
+typedef struct fcontext *fcontext_t;
 typedef struct transfer_t {
     fcontext_t fctx;
     void *data;
@@ -27,13 +26,24 @@ fcontext_t FCONTEXT_CALL make_fcontext(void *sp, size_t size, void (*fn)(transfe
 // NOTE: currently unused
 transfer_t FCONTEXT_CALL ontop_fcontext(const fcontext_t to, void *vp, transfer_t (*fn)(transfer_t));
 
+#endif
+
+typedef struct fcontext_fiber {
+	fcontext_t fctx;
+	char *stack;
+	size_t stack_size;
+	KOISHI_VALGRIND_STACK_ID(valgrind_stack_id)
+} koishi_fiber_t;
+
+#include "../fiber.h"
+
 static void koishi_fiber_swap(koishi_fiber_t *from, koishi_fiber_t *to) {
 	transfer_t tf = jump_fcontext(to->fctx, from);
-	from = tf.data;
+	from = (koishi_fiber_t*)tf.data;
 	from->fctx = tf.fctx;
 }
 
-static KOISHI_NORETURN void co_entry(transfer_t tf) {
+KOISHI_NORETURN static void co_entry(transfer_t tf) {
 	koishi_coroutine_t *co = co_current;
 	assert(tf.data == &co->caller->fiber);
 	((koishi_fiber_t*)tf.data)->fctx = tf.fctx;
@@ -50,7 +60,7 @@ static inline void init_fiber_fcontext(koishi_fiber_t *fiber) {
 }
 
 static void koishi_fiber_init(koishi_fiber_t *fiber, size_t min_stack_size) {
-	fiber->stack = alloc_stack(min_stack_size, &fiber->stack_size);
+	fiber->stack = (char*)alloc_stack(min_stack_size, &fiber->stack_size);
 	KOISHI_VALGRIND_STACK_REGISTER(fiber->valgrind_stack_id, fiber->stack, fiber->stack + fiber->stack_size);
 	init_fiber_fcontext(fiber);
 }

src/fcontext/meson.build

@@ -74,6 +74,7 @@ foreach routine : fcontext_asm_routines
     endif
 endforeach
 
+fcontext_deps = []
 fcontext_args = ['-DFCONTEXT_CALL=@0@'.format(fcontext_callconv)]
 fcontext_external_args = []
 fcontext_external_link_args = []

src/fiber.h

@@ -64,7 +64,7 @@ static void koishi_return_to_caller(koishi_coroutine_t *from, int state) {
 	koishi_swap_coroutine(from, from->caller, state);
 }
 
-static inline KOISHI_NORETURN void koishi_entry(koishi_coroutine_t *co) {
+KOISHI_NORETURN static inline void koishi_entry(koishi_coroutine_t *co) {
 	co->userdata = co->entry(co->userdata);
 	koishi_return_to_caller(co, KOISHI_DEAD);
 	KOISHI_UNREACHABLE;
@@ -98,7 +98,7 @@ KOISHI_API void *koishi_yield(void *arg) {
 	return co->userdata;
 }
 
-KOISHI_API KOISHI_NORETURN void koishi_die(void *arg) {
+KOISHI_NORETURN KOISHI_API void koishi_die(void *arg) {
 	koishi_coroutine_t *co = koishi_active();
 	co->userdata = arg;
 	koishi_return_to_caller(co, KOISHI_DEAD);

src/meson.build

@@ -3,8 +3,11 @@ koishi_src = files(
     'stack_alloc.c',
 )
 
+koishi_deps = []
+
 backends = [
     'fcontext',
+    'boost_fcontext',
     'win32fiber',
     'emscripten',
     'ucontext_e2k',
@@ -41,6 +44,7 @@ if impl == 'auto'
 endif
 
 koishi_src += get_variable('@0@_src'.format(impl))
+koishi_deps += get_variable('@0@_deps'.format(impl))
 koishi_args += get_variable('@0@_args'.format(impl))
 koishi_external_args += get_variable('@0@_external_args'.format(impl))
 koishi_external_link_args += get_variable('@0@_external_link_args'.format(impl))
@@ -54,9 +58,11 @@ endif
 libkoishi = library('koishi',
     koishi_src,
     c_args : koishi_args,
+    cpp_args : koishi_args,
     gnu_symbol_visibility : 'hidden',
     implicit_include_directories : false,
     include_directories : koishi_incdirs,
+    dependencies : koishi_deps,
     install : not meson.is_subproject(),
     soversion : soversion,
 )

src/ucontext/meson.build

@@ -12,6 +12,7 @@ else
 endif
 
 ucontext_src = files('ucontext.c')
+ucontext_deps = []
 ucontext_args = []
 ucontext_external_args = []
 ucontext_external_link_args = []

src/ucontext_e2k/meson.build

@@ -11,6 +11,7 @@ foreach fun : ['getcontext', 'makecontext_e2k', 'swapcontext', 'freecontext_e2k'
 endforeach
 
 ucontext_e2k_src = files('ucontext_e2k.c')
+ucontext_e2k_deps = []
 ucontext_e2k_args = []
 ucontext_e2k_external_args = []
 ucontext_e2k_external_link_args = []

src/ucontext_sjlj/meson.build

@@ -12,6 +12,7 @@ else
 endif
 
 ucontext_sjlj_src = files('ucontext_sjlj.c')
+ucontext_sjlj_deps = []
 ucontext_sjlj_args = ['-U_FORTIFY_SOURCE']  # avoid longjmp false positives
 ucontext_sjlj_external_args = []
 ucontext_sjlj_external_link_args = []

src/win32fiber/meson.build

@@ -2,6 +2,7 @@
 win32fiber_supported = os_is_windows
 
 win32fiber_src = files('win32fiber.c')
+win32fiber_deps = []
 win32fiber_args = []
 win32fiber_external_args = []
 win32fiber_external_link_args = []