X-Git-Url: http://git.ozlabs.org/?p=ccan;a=blobdiff_plain;f=ccan%2Fgenerator%2Fgenerator.h;h=7122f554dd8987cde3ed83d7a03db9a380a36bec;hp=6b2bd92fe526411a56d254969d4d8b3e6f35ad55;hb=a240178097376329b4567a6728952daa89362771;hpb=707a8c0a899a4b645bcf778f7ea79565d6f3f13e

diff --git a/ccan/generator/generator.h b/ccan/generator/generator.h
index 6b2bd92f..7122f554 100644
--- a/ccan/generator/generator.h
+++ b/ccan/generator/generator.h
@@ -3,10 +3,6 @@
 #define CCAN_GENERATOR_H
 #include "config.h"
 
-#if !HAVE_UCONTEXT
-#error Generators require working ucontext.h functions
-#endif
-
 #if !HAVE_TYPEOF
 #error Generators require typeof
 #endif
@@ -18,19 +14,22 @@
 #include <assert.h>
 #include <stddef.h>
 #include <stdbool.h>
-#include <ucontext.h>
 
-#include <ccan/ptrint/ptrint.h>
-#include <ccan/build_assert/build_assert.h>
 #include <ccan/cppmagic/cppmagic.h>
+#include <ccan/compiler/compiler.h>
+#include <ccan/coroutine/coroutine.h>
+
+#if !COROUTINE_AVAILABLE
+#error Generators require coroutines
+#endif
 
 /*
  * Internals - included just for the use of inlines and macros
  */
 
 struct generator_ {
-	ucontext_t gen;
-	ucontext_t caller;
+	struct coroutine_state gen;
+	struct coroutine_state caller;
 	bool complete;
 	void *base;
 };
@@ -40,20 +39,18 @@ static inline struct generator_ *generator_state_(const void *ret)
 	return (struct generator_ *)ret - 1;
 }
 
+static inline void *generator_argp_(const void *ret)
+{
+	return generator_state_(ret)->base;
+}
+
 struct generator_incomplete_;
 
 #define generator_rtype_(gen_)			\
 	typeof((*(gen_))((struct generator_incomplete_ *)NULL))
 
-#if HAVE_POINTER_SAFE_MAKECONTEXT
-#define generator_wrapper_args_()	void *ret
-#else
-#define generator_wrapper_args_()	int lo, int hi
-#endif
-typedef void generator_wrapper_(generator_wrapper_args_());
-
-void *generator_new_(generator_wrapper_ *fn, size_t retsize);
-void generator_free_(void *ret);
+void *generator_new_(void (*fn)(void *), size_t retsize);
+void generator_free_(void *ret, size_t retsize);
 
 /*
  * API
@@ -77,8 +74,8 @@ void generator_free_(void *ret);
  * Example:
  *	generator_declare(count_to_3, int);
  */
-#define generator_declare(name_, rtype_)	\
-	generator_t(rtype_) name_(void)
+#define generator_declare(name_, rtype_, ...)	\
+	generator_t(rtype_) name_(generator_parms_outer_(__VA_ARGS__))
 
 /**
  * generator_def - define a generator function
@@ -97,32 +94,56 @@ void generator_free_(void *ret);
  *		generator_yield(3);
  *	}
  */
-#define generator_def_(name_, rtype_, storage_)				\
-	static void name_##_generator_(rtype_ *ret_);			\
-	static void name_##_generator__(generator_wrapper_args_())	\
+#define generator_parm_(t_, n_)			t_ n_
+#define generator_parms_(...)						\
+	CPPMAGIC_2MAP(generator_parm_, __VA_ARGS__)
+#define generator_parms_inner_(...)					\
+	CPPMAGIC_IFELSE(CPPMAGIC_NONEMPTY(__VA_ARGS__))			\
+		(, generator_parms_(__VA_ARGS__))()
+#define generator_parms_outer_(...)					\
+	CPPMAGIC_IFELSE(CPPMAGIC_NONEMPTY(__VA_ARGS__))	\
+		(generator_parms_(__VA_ARGS__))(void)
+#define generator_argfield_(t_, n_)		t_ n_;
+#define generator_argstruct_(...)					\
+	struct {							\
+		CPPMAGIC_JOIN(, CPPMAGIC_2MAP(generator_argfield_,	\
+					      __VA_ARGS__))		\
+	}
+#define generator_arg_unpack_(t_, n_)		args->n_
+#define generator_args_unpack_(...)		\
+	CPPMAGIC_IFELSE(CPPMAGIC_NONEMPTY(__VA_ARGS__))			\
+		(, CPPMAGIC_2MAP(generator_arg_unpack_, __VA_ARGS__))()
+#define generator_arg_pack_(t_, n_)		args->n_ = n_
+#define generator_args_pack_(...)					\
+	CPPMAGIC_JOIN(;, CPPMAGIC_2MAP(generator_arg_pack_, __VA_ARGS__))
+#define generator_def_(name_, rtype_, storage_, ...)			\
+	static void name_##_generator_(rtype_ *ret_			\
+				       generator_parms_inner_(__VA_ARGS__)); \
+	static void name_##_generator__(void *ret)			\
 	{								\
 		struct generator_ *gen;					\
-		CPPMAGIC_IFELSE(HAVE_POINTER_SAFE_MAKECONTEXT)		\
-			()						\
-			(ptrdiff_t hilo = ((ptrdiff_t)hi << (8*sizeof(int))) \
-			 	+ (ptrdiff_t)lo;			\
-			rtype_ *ret = (rtype_ *)int2ptr(hilo);		\
-			BUILD_ASSERT(sizeof(struct generator_ *)	\
-				     <= 2*sizeof(int));)		\
+		UNNEEDED generator_argstruct_(__VA_ARGS__) *args;	\
 		gen = generator_state_(ret);				\
-		name_##_generator_(ret);				\
+		args = generator_argp_(ret);				\
+		name_##_generator_(ret generator_args_unpack_(__VA_ARGS__)); \
 		gen->complete = true;					\
-		setcontext(&gen->caller);				\
+		coroutine_jump(&gen->caller);				\
 		assert(0);						\
 	}								\
-	storage_ generator_t(rtype_) name_(void)			\
+	storage_ generator_t(rtype_)					\
+	name_(generator_parms_outer_(__VA_ARGS__))			\
 	{								\
-		return generator_new_(name_##_generator__,		\
-				      sizeof(rtype_));			\
+		generator_t(rtype_) gen = generator_new_(name_##_generator__, \
+							 sizeof(rtype_)); \
+		UNNEEDED generator_argstruct_(__VA_ARGS__) *args =	\
+			generator_argp_(gen);				\
+		generator_args_pack_(__VA_ARGS__);			\
+		return gen;						\
 	}								\
-	static void name_##_generator_(rtype_ *ret_)
-#define generator_def(name_, rtype_)		\
-	generator_def_(name_, rtype_, )
+	static void name_##_generator_(rtype_ *ret_			\
+				       generator_parms_inner_(__VA_ARGS__))
+#define generator_def(name_, rtype_, ...)	\
+	generator_def_(name_, rtype_, , __VA_ARGS__)
 
 /**
  * generator_def_static - define a private / local generator function
@@ -132,8 +153,8 @@ void generator_free_(void *ret);
  * As generator_def, but the resulting generator function will be
  * local to this module.
  */
-#define generator_def_static(name_, rtype_)	\
-	generator_def_(name_, rtype_, static)
+#define generator_def_static(name_, rtype_, ...)	\
+	generator_def_(name_, rtype_, static, __VA_ARGS__)
 
 /**
  * generator_yield - yield (return) a value from a generator
@@ -147,10 +168,8 @@ void generator_free_(void *ret);
 #define generator_yield(val_)						\
 	do {								\
 		struct generator_ *gen_ = generator_state_(ret_);	\
-		int rc;							\
 		*(ret_) = (val_);					\
-		rc = swapcontext(&gen_->gen, &gen_->caller);		\
-		assert(rc == 0);					\
+		coroutine_switch(&gen_->gen, &gen_->caller);		\
 	} while (0)
 
 /**
@@ -165,13 +184,11 @@ void generator_free_(void *ret);
 static inline void *generator_next_(void *ret_)
 {
 	struct generator_ *gen = generator_state_(ret_);
-	int rc;
 
 	if (gen->complete)
 		return NULL;
 
-	rc = swapcontext(&gen->caller, &gen->gen);
-	assert(rc == 0);
+	coroutine_switch(&gen->caller, &gen->gen);
 
 	return gen->complete ? NULL : ret_;
 }
@@ -197,6 +214,7 @@ static inline void *generator_next_(void *ret_)
 	})
 
 #define generator_free(gen_)					\
-	generator_free_((generator_rtype_(gen_) *)(gen_))
+	generator_free_((generator_rtype_(gen_) *)(gen_),	\
+			sizeof(generator_rtype_(gen_)))
 
 #endif /* CCAN_GENERATOR_H */