--- libcoro/coro.c	2012/12/05 13:10:21	1.65
+++ libcoro/coro.c	2012/12/07 14:21:09	1.66
@@ -40,6 +40,7 @@
 
 #include "coro.h"
 
+#include <stddef.h>
 #include <string.h>
 
 /*****************************************************************************/
@@ -241,7 +242,7 @@
 # endif
 
 void
-coro_create (coro_context *ctx, coro_func coro, void *arg, void *sptr, long ssize)
+coro_create (coro_context *ctx, coro_func coro, void *arg, void *sptr, size_t ssize)
 {
   coro_context nctx;
 # if CORO_SJLJ
@@ -443,7 +444,7 @@
 }
 
 void
-coro_create (coro_context *ctx, coro_func coro, void *arg, void *sptr, long ssize)
+coro_create (coro_context *ctx, coro_func coro, void *arg, void *sptr, size_t ssize)
 {
   static coro_context nctx;
   static int once;
@@ -508,7 +509,10 @@
 #elif CORO_FIBER
 
 #define WIN32_LEAN_AND_MEAN
-#define _WIN32_WINNT 0x0400
+#if _WIN32_WINNT < 0x0400
+  #undef _WIN32_WINNT
+  #define _WIN32_WINNT 0x0400
+#endif
 #include <windows.h>
 
 VOID CALLBACK
@@ -534,7 +538,7 @@
 }
 
 void
-coro_create (coro_context *ctx, coro_func coro, void *arg, void *sptr, long ssize)
+coro_create (coro_context *ctx, coro_func coro, void *arg, void *sptr, size_t ssize)
 {
   ctx->fiber = 0;
   ctx->coro  = coro;
@@ -553,6 +557,151 @@
 }
 
 #else
-# error unsupported backend
+  #error unsupported backend
+#endif
+
+/*****************************************************************************/
+/* stack management                                                          */
+/*****************************************************************************/
+#if CORO_STACKALLOC
+
+#include <stdlib.h>
+
+#ifndef _WIN32
+# include <unistd.h>
+#endif
+
+#if CORO_USE_VALGRIND
+# include <valgrind/valgrind.h>
+#endif
+
+#if _POSIX_MAPPED_FILES
+# include <sys/mman.h>
+# define CORO_MMAP 1
+# ifndef MAP_ANONYMOUS
+#  ifdef MAP_ANON
+#   define MAP_ANONYMOUS MAP_ANON
+#  else
+#   undef CORO_MMAP
+#  endif
+# endif
+# include <limits.h>
+#else
+# undef CORO_MMAP
+#endif
+
+#if _POSIX_MEMORY_PROTECTION
+# ifndef CORO_GUARDPAGES
+#  define CORO_GUARDPAGES 4
+# endif
+#else
+# undef CORO_GUARDPAGES
+#endif
+
+#if !CORO_MMAP
+# undef CORO_GUARDPAGES
+#endif
+
+#if !__i386 && !__x86_64 && !__powerpc && !__m68k && !__alpha && !__mips && !__sparc64
+# undef CORO_GUARDPAGES
+#endif
+
+#ifndef CORO_GUARDPAGES
+# define CORO_GUARDPAGES 0
+#endif
+
+#if !PAGESIZE
+  #if !CORO_MMAP
+    #define PAGESIZE 4096
+  #else
+    static size_t
+    coro_pagesize (void)
+    {
+      static size_t pagesize;
+
+      if (!pagesize)
+        pagesize = sysconf (_SC_PAGESIZE);
+
+      return pagesize;
+    }
+
+    #define PAGESIZE coro_pagesize ()
+  #endif
+#endif
+
+int
+coro_stack_alloc (struct coro_stack *stack, unsigned int size)
+{
+  if (!size)
+    size = 256 * 1024;
+
+  stack->sptr = 0;
+  stack->ssze = ((size_t)size * sizeof (void *) + PAGESIZE - 1) / PAGESIZE * PAGESIZE;
+
+#if CORO_FIBER
+
+  stack->sptr = (void *)stack;
+  return 1;
+
+#else
+
+  size_t ssze = stack->ssze + CORO_GUARDPAGES * PAGESIZE;
+  void *base;
+
+  #if CORO_MMAP
+    /* mmap supposedly does allocate-on-write for us */
+    base = mmap (0, ssze, PROT_READ | PROT_WRITE | PROT_EXEC, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+
+    if (base == (void *)-1)
+      {
+        /* some systems don't let us have executable heap */
+        /* we assume they won't need executable stack in that case */
+        base = mmap (0, ssze, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+
+        if (base == (void *)-1)
+          return 0;
+      }
+
+    #if CORO_GUARDPAGES
+      mprotect (base, CORO_GUARDPAGES * PAGESIZE, PROT_NONE);
+    #endif
+
+    base = (void*)((char *)base + CORO_GUARDPAGES * PAGESIZE);
+  #else
+    base = malloc (ssze);
+    if (!base)
+      return 0;
+  #endif
+
+  #if CORO_USE_VALGRIND
+    stack->valgrind_id = VALGRIND_STACK_REGISTER ((char *)base, (char *)ssze - CORO_GUARDPAGES * PAGESIZE);
+  #endif
+
+  stack->sptr = base;
+  return 1;
+
+#endif
+}
+
+void
+coro_stack_free (struct coro_stack *stack)
+{
+#if CORO_FIBER
+  /* nop */
+#else
+  #if CORO_USE_VALGRIND
+    VALGRIND_STACK_DEREGISTER (stack->valgrind_id);
+  #endif
+
+  #if CORO_MMAP
+    if (stack->sptr)
+      munmap ((void*)((char *)stack->sptr - CORO_GUARDPAGES * PAGESIZE),
+              stack->ssze                 + CORO_GUARDPAGES * PAGESIZE);
+  #else
+    free (stack->sptr);
+  #endif
+#endif
+}
+
 #endif