--- libcoro/coro.h	2008/10/30 09:44:31	1.28
+++ libcoro/coro.h	2011/05/30 02:21:54	1.45
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2001-2008 Marc Alexander Lehmann <schmorp@schmorp.de>
+ * Copyright (c) 2001-2009 Marc Alexander Lehmann <schmorp@schmorp.de>
  * 
  * Redistribution and use in source and binary forms, with or without modifica-
  * tion, are permitted provided that the following conditions are met:
@@ -56,11 +56,30 @@
  * 2008-04-04 New (but highly unrecommended) pthreads backend.
  * 2008-04-24 Reinstate CORO_LOSER (had wrong stack adjustments).
  * 2008-10-30 Support assembly method on x86 with and without frame pointer.
+ * 2008-11-03 Use a global asm statement for CORO_ASM, idea by pippijn.
+ * 2008-11-05 Hopefully fix misaligned stacks with CORO_ASM/SETJMP.
+ * 2008-11-07 rbp wasn't saved in CORO_ASM on x86_64.
+ *            introduce coro_destroy, which is a nop except for pthreads.
+ *            speed up CORO_PTHREAD. Do no longer leak threads either.
+ *            coro_create now allows one to create source coro_contexts.
+ *            do not rely on makecontext passing a void * correctly.
+ *            try harder to get _setjmp/_longjmp.
+ *            major code cleanup/restructuring.
+ * 2008-11-10 the .cfi hacks are no longer needed.
+ * 2008-11-16 work around a freebsd pthread bug.
+ * 2008-11-19 define coro_*jmp symbols for easier porting.
+ * 2009-06-23 tentative win32-backend support for mingw32 (Yasuhiro Matsumoto).
+ * 2010-12-03 tentative support for uclibc (which lacks all sorts of things).
+ * 2011-05-30 set initial callee-saved-registers to zero with CORO_ASM.
  */
 
 #ifndef CORO_H
 #define CORO_H
 
+#if __cplusplus
+extern "C" {
+#endif
+
 #define CORO_VERSION 2
 
 /*
@@ -107,11 +126,13 @@
  * -DCORO_ASM
  *
  *    Handcoded assembly, known to work only on a few architectures/ABI:
- *    ELF Linux x86 && amd64 when gcc is used and optimisation is turned on.
+ *    GCC + x86/IA32 and amd64/x86_64 + GNU/Linux and a few BSDs.
  *
  * -DCORO_PTHREAD
  *
  *    Use the pthread API. You have to provide <pthread.h> and -lpthread.
+ *    This is likely the slowest backend, and it also does not support fork(),
+ *    so avoid it at all costs.
  *
  * If you define neither of these symbols, coro.h will try to autodetect
  * the model. This currently works for CORO_LOSER only. For the other
@@ -136,8 +157,14 @@
  * uninitialised coro_context, it expects a pointer to the entry function
  * and the single pointer value that is given to it as argument.
  *
- * Allocating/deallocating the stack is your own responsibility, so there is
- * no coro_destroy function.
+ * Allocating/deallocating the stack is your own responsibility.
+ *
+ * As a special case, if coro, arg, sptr and ssize are all zero,
+ * then an "empty" coro_context will be created that is suitable
+ * as an initial source for coro_transfer.
+ *
+ * This function is not reentrant, but putting a mutex around it
+ * will work.
  */
 void coro_create (coro_context *ctx, /* an uninitialised coro_context */
                   coro_func coro,    /* the coroutine code to be executed */
@@ -149,8 +176,24 @@
  * The following prototype defines the coroutine switching function. It is
  * usually implemented as a macro, so watch out.
  *
-void coro_transfer(coro_context *prev, coro_context *next);
+ * This function is thread-safe and reentrant.
+ */
+#if 0
+void coro_transfer (coro_context *prev, coro_context *next);
+#endif
+
+/*
+ * The following prototype defines the coroutine destroy function. It is
+ * usually implemented as a macro, so watch out. It also serves
+ * no purpose unless you want to use the CORO_PTHREAD backend,
+ * where it is used to clean up the thread. You are responsible
+ * for freeing the stack and the context itself.
+ *
+ * This function is thread-safe and reentrant.
  */
+#if 0
+void coro_destroy (coro_context *ctx);
+#endif
 
 /*
  * That was it. No other user-visible functions are implemented here.
@@ -186,6 +229,7 @@
 };
 
 # define coro_transfer(p,n) swapcontext (&((p)->uc), &((n)->uc))
+# define coro_destroy(ctx) (void *)(ctx)
 
 #elif CORO_SJLJ || CORO_LOSER || CORO_LINUX || CORO_IRIX
 
@@ -193,39 +237,68 @@
 #  define _GNU_SOURCE /* for linux libc */
 # endif
 
+# if !CORO_LOSER
+#  include <unistd.h>
+# endif
+
+/* solaris is hopelessly borked, it expands _XOPEN_UNIX to nothing */
+# if __sun
+#  undef _XOPEN_UNIX
+#  define _XOPEN_UNIX 1
+# endif
+
 # include <setjmp.h>
 
+# if _XOPEN_UNIX > 0 || defined (_setjmp)
+#  define coro_jmp_buf      jmp_buf
+#  define coro_setjmp(env)  _setjmp (env)
+#  define coro_longjmp(env) _longjmp ((env), 1)
+# elif CORO_LOSER
+#  define coro_jmp_buf      jmp_buf
+#  define coro_setjmp(env)  setjmp (env)
+#  define coro_longjmp(env) longjmp ((env), 1)
+# else
+#  define coro_jmp_buf      sigjmp_buf
+#  define coro_setjmp(env)  sigsetjmp (env, 0)
+#  define coro_longjmp(env) siglongjmp ((env), 1)
+# endif
+
 struct coro_context {
-  jmp_buf env;
+  coro_jmp_buf env;
 };
 
-# if CORO_LINUX || (_XOPEN_SOURCE >= 600)
-#  define coro_transfer(p,n) do { if (!_setjmp ((p)->env)) _longjmp ((n)->env, 1); } while (0)
-# else
-#  define coro_transfer(p,n) do { if (!setjmp  ((p)->env)) longjmp  ((n)->env, 1); } while (0)
-# endif
+# define coro_transfer(p,n) do { if (!coro_setjmp ((p)->env)) coro_longjmp ((n)->env); } while (0)
+# define coro_destroy(ctx) (void *)(ctx)
 
 #elif CORO_ASM
 
 struct coro_context {
-  volatile void **sp;
+  void **sp; /* must be at offset 0 */
 };
 
 void __attribute__ ((__noinline__, __regparm__(2)))
-     coro_transfer (coro_context *prev, coro_context *next);
+coro_transfer (coro_context *prev, coro_context *next);
+
+# define coro_destroy(ctx) (void *)(ctx)
 
 #elif CORO_PTHREAD
 
-#include <pthread.h>
+# include <pthread.h>
 
 extern pthread_mutex_t coro_mutex;
 
 struct coro_context {
-  pthread_cond_t c;
+  pthread_cond_t cv;
+  pthread_t id;
 };
 
 void coro_transfer (coro_context *prev, coro_context *next);
+void coro_destroy (coro_context *ctx);
+
+#endif
 
+#if __cplusplus
+}
 #endif
 
 #endif