2 files changed, 44 insertions, 40 deletions

diff --git a/coroutine/x86/Context.s b/coroutine/x86/Context.S
index 5fc0cccc24..b04e71aa1c 100644
--- a/coroutine/x86/Context.s
+++ b/coroutine/x86/Context.S
@@ -2,17 +2,15 @@
 ##  This file is part of the "Coroutine" project and released under the MIT License.
 ##
 ##  Created by Samuel Williams on 3/11/2018.
-##  Copyright, 2018, by Samuel Williams. All rights reserved.
+##  Copyright, 2018, by Samuel Williams.
 ##
 
-.text
+#define TOKEN_PASTE(x,y) x##y
 
-.globl coroutine_transfer
-coroutine_transfer:
+.text
 
-# For older linkers
-.globl _coroutine_transfer
-_coroutine_transfer:
+.globl PREFIXED_SYMBOL(coroutine_transfer)
+PREFIXED_SYMBOL(coroutine_transfer):
 
 	# Save caller registers
 	pushl %ebp
@@ -37,3 +35,7 @@ _coroutine_transfer:
 
 	# Jump to the address on the stack
 	ret
+
+#if (defined(__linux__) || defined(__FreeBSD__)) && defined(__ELF__)
+.section .note.GNU-stack,"",%progbits
+#endif
diff --git a/coroutine/x86/Context.h b/coroutine/x86/Context.h
index 82fd1b75ff..f33b338eab 100644
--- a/coroutine/x86/Context.h
+++ b/coroutine/x86/Context.h
@@ -1,59 +1,61 @@
+#ifndef COROUTINE_X86_CONTEXT_H
+#define COROUTINE_X86_CONTEXT_H 1
+
 /*
  *  This file is part of the "Coroutine" project and released under the MIT License.
  *
  *  Created by Samuel Williams on 3/11/2018.
- *  Copyright, 2018, by Samuel Williams. All rights reserved.
+ *  Copyright, 2018, by Samuel Williams.
 */
 
 #pragma once
 
 #include <assert.h>
+#include <stddef.h>
+#include <stdint.h>
 #include <string.h>
 
-#if __cplusplus
-extern "C" {
-#endif
-
-#define COROUTINE void __attribute__((fastcall))
+#define COROUTINE __attribute__((noreturn, fastcall)) void
+#define COROUTINE_LIMITED_ADDRESS_SPACE
 
-const size_t COROUTINE_REGISTERS = 4;
+enum {COROUTINE_REGISTERS = 4};
 
-typedef struct
+struct coroutine_context
 {
-        void **stack_pointer;
-} coroutine_context;
+    void **stack_pointer;
+    void *argument;
+};
 
-typedef void(* coroutine_start)(coroutine_context *from, coroutine_context *self) __attribute__((fastcall));
+typedef COROUTINE(* coroutine_start)(struct coroutine_context *from, struct coroutine_context *self) __attribute__((fastcall));
 
-void coroutine_initialize(
-        coroutine_context *context,
-        coroutine_start start,
-        void *stack_pointer,
-        size_t stack_size
+static inline void coroutine_initialize_main(struct coroutine_context * context) {
+    context->stack_pointer = NULL;
+}
+
+static inline void coroutine_initialize(
+    struct coroutine_context *context,
+    coroutine_start start,
+    void *stack,
+    size_t size
 ) {
-        /* Force 16-byte alignment */
-        context->stack_pointer = (void**)((uintptr_t)stack_pointer & ~0xF);
+    assert(start && stack && size >= 1024);
 
-        if (!start) {
-                assert(!context->stack_pointer);
-                /* We are main coroutine for this thread */
-                return;
-        }
+    // Stack grows down. Force 16-byte alignment.
+    char * top = (char*)stack + size;
+    context->stack_pointer = (void**)((uintptr_t)top & ~0xF);
 
-        *--context->stack_pointer = NULL;
-        *--context->stack_pointer = (void*)start;
+    *--context->stack_pointer = NULL;
+    *--context->stack_pointer = (void*)(uintptr_t)start;
 
-        context->stack_pointer -= COROUTINE_REGISTERS;
-        memset(context->stack_pointer, 0, sizeof(void*) * COROUTINE_REGISTERS);
+    context->stack_pointer -= COROUTINE_REGISTERS;
+    memset(context->stack_pointer, 0, sizeof(void*) * COROUTINE_REGISTERS);
 }
 
-coroutine_context * coroutine_transfer(coroutine_context * current, coroutine_context * target) __attribute__((fastcall));
+struct coroutine_context * coroutine_transfer(struct coroutine_context * current, struct coroutine_context * target) __attribute__((fastcall));
 
-inline void coroutine_destroy(coroutine_context * context)
+static inline void coroutine_destroy(struct coroutine_context * context)
 {
-        context->stack_pointer = NULL;
+    context->stack_pointer = NULL;
 }
 
-#if __cplusplus
-}
-#endif
+#endif /* COROUTINE_X86_CONTEXT_H */