libcoro/coro.c

/*
 * Copyright (c) 2001-2011 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:
 * 
 *   1.  Redistributions of source code must retain the above copyright notice,
 *       this list of conditions and the following disclaimer.
 * 
 *   2.  Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER-
 * CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO
 * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE-
 * CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH-
 * ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 * OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * Alternatively, the contents of this file may be used under the terms of
 * the GNU General Public License ("GPL") version 2 or any later version,
 * in which case the provisions of the GPL are applicable instead of
 * the above. If you wish to allow the use of your version of this file
 * only under the terms of the GPL and not to allow others to use your
 * version of this file under the BSD license, indicate your decision
 * by deleting the provisions above and replace them with the notice
 * and other provisions required by the GPL. If you do not delete the
 * provisions above, a recipient may use your version of this file under
 * either the BSD or the GPL.
 *
 * This library is modelled strictly after Ralf S. Engelschalls article at
 * http://www.gnu.org/software/pth/rse-pmt.ps. So most of the credit must
 * go to Ralf S. Engelschall <rse@engelschall.com>.
 */

#include "coro.h"

#include <string.h>

/*****************************************************************************/
/* ucontext/setjmp/asm backends                                              */
/*****************************************************************************/
#if CORO_UCONTEXT || CORO_SJLJ || CORO_LOSER || CORO_LINUX || CORO_IRIX || CORO_ASM

# if CORO_UCONTEXT
#  include <stddef.h>
# endif

# if !defined(STACK_ADJUST_PTR)
#  if __sgi
/* IRIX is decidedly NON-unix */
#   define STACK_ADJUST_PTR(sp,ss) ((char *)(sp) + (ss) - 8)
#   define STACK_ADJUST_SIZE(sp,ss) ((ss) - 8)
#  elif (__i386__ && CORO_LINUX) || (_M_IX86 && CORO_LOSER)
#   define STACK_ADJUST_PTR(sp,ss) ((char *)(sp) + (ss))
#   define STACK_ADJUST_SIZE(sp,ss) (ss)
#  elif (__amd64__ && CORO_LINUX) || ((_M_AMD64 || _M_IA64) && CORO_LOSER)
#   define STACK_ADJUST_PTR(sp,ss) ((char *)(sp) + (ss) - 8)
#   define STACK_ADJUST_SIZE(sp,ss) (ss)
#  else
#   define STACK_ADJUST_PTR(sp,ss) (sp)
#   define STACK_ADJUST_SIZE(sp,ss) (ss)
#  endif
# endif

# include <stdlib.h>

# if CORO_SJLJ
#  include <stdio.h>
#  include <signal.h>
#  include <unistd.h>
# endif

static coro_func coro_init_func;
static void *coro_init_arg;
static coro_context *new_coro, *create_coro;

static void
coro_init (void)
{
  volatile coro_func func = coro_init_func;
  volatile void *arg = coro_init_arg;

  coro_transfer (new_coro, create_coro);

#if __linux && __amd64
  /* we blindly assume on any __linux with __amd64 we have a new enough gas with .cfi_undefined support */
  asm (".cfi_undefined rip");
#endif

  func ((void *)arg);

  /* the new coro returned. bad. just abort() for now */
  abort ();
}

# if CORO_SJLJ

static volatile int trampoline_done;

/* trampoline signal handler */
static void
trampoline (int sig)
{
  if (coro_setjmp (new_coro->env))
    coro_init (); /* start it */
  else
    trampoline_done = 1;
}

# endif

# if CORO_ASM

  asm (
       ".text\n"
       ".globl coro_transfer\n"
       ".type coro_transfer, @function\n"
       "coro_transfer:\n"
       /* windows, of course, gives a shit on the amd64 ABI and uses different registers */
       /* http://blogs.msdn.com/freik/archive/2005/03/17/398200.aspx */
       #if __amd64
         #ifdef _WIN32
           #define NUM_SAVED 8
           "\tpush %rsi\n"
           "\tpush %rdi\n"
           "\tpush %rbp\n"
           "\tpush %rbx\n"
           "\tpush %r12\n"
           "\tpush %r13\n"
           "\tpush %r14\n"
           "\tpush %r15\n"
           #if CORO_WIN_TIB
             "\tpush %gs:0x0\n"
             "\tpush %gs:0x8\n"
             "\tpush %gs:0xc\n"
           #endif
           "\tmov %rsp, (%rcx)\n"
           "\tmov (%rdx), %rsp\n"
           #if CORO_WIN_TIB
             "\tpop %gs:0xc\n"
             "\tpop %gs:0x8\n"
             "\tpop %gs:0x0\n"
           #endif
           "\tpop %r15\n"
           "\tpop %r14\n"
           "\tpop %r13\n"
           "\tpop %r12\n"
           "\tpop %rbx\n"
           "\tpop %rbp\n"
           "\tpop %rdi\n"
           "\tpop %rsi\n"
         #else
           #define NUM_SAVED 6
           "\tpush %rbp\n"
           "\tpush %rbx\n"
           "\tpush %r12\n"
           "\tpush %r13\n"
           "\tpush %r14\n"
           "\tpush %r15\n"
           "\tmov %rsp, (%rdi)\n"
           "\tmov (%rsi), %rsp\n"
           "\tpop %r15\n"
           "\tpop %r14\n"
           "\tpop %r13\n"
           "\tpop %r12\n"
           "\tpop %rbx\n"
           "\tpop %rbp\n"
         #endif
       #elif __i386
         #define NUM_SAVED 4
         "\tpush %ebp\n"
         "\tpush %ebx\n"
         "\tpush %esi\n"
         "\tpush %edi\n"
         #if CORO_WIN_TIB
           "\tpush %fs:0\n"
           "\tpush %fs:4\n"
           "\tpush %fs:8\n"
         #endif
         "\tmov %esp, (%eax)\n"
         "\tmov (%edx), %esp\n"
         #if CORO_WIN_TIB
           "\tpop %fs:8\n"
           "\tpop %fs:4\n"
           "\tpop %fs:0\n"
         #endif
         "\tpop %edi\n"
         "\tpop %esi\n"
         "\tpop %ebx\n"
         "\tpop %ebp\n"
       #else
         #error unsupported architecture
       #endif
       "\tret\n"
  );

# endif

void
coro_create (coro_context *ctx, coro_func coro, void *arg, void *sptr, long ssize)
{
  coro_context nctx;
# if CORO_SJLJ
  stack_t ostk, nstk;
  struct sigaction osa, nsa;
  sigset_t nsig, osig;
# endif

  if (!coro)
    return;

  coro_init_func = coro;
  coro_init_arg  = arg;

  new_coro    = ctx;
  create_coro = &nctx;

# if CORO_SJLJ
  /* we use SIGUSR2. first block it, then fiddle with it. */

  sigemptyset (&nsig);
  sigaddset (&nsig, SIGUSR2);
  sigprocmask (SIG_BLOCK, &nsig, &osig);

  nsa.sa_handler = trampoline;
  sigemptyset (&nsa.sa_mask);
  nsa.sa_flags = SA_ONSTACK;

  if (sigaction (SIGUSR2, &nsa, &osa))
    {
      perror ("sigaction");
      abort ();
    }

  /* set the new stack */
  nstk.ss_sp    = STACK_ADJUST_PTR (sptr, ssize); /* yes, some platforms (IRIX) get this wrong. */
  nstk.ss_size  = STACK_ADJUST_SIZE (sptr, ssize);
  nstk.ss_flags = 0;

  if (sigaltstack (&nstk, &ostk) < 0)
    {
      perror ("sigaltstack");
      abort ();
    }

  trampoline_done = 0;
  kill (getpid (), SIGUSR2);
  sigfillset (&nsig); sigdelset (&nsig, SIGUSR2);

  while (!trampoline_done)
    sigsuspend (&nsig);

  sigaltstack (0, &nstk);
  nstk.ss_flags = SS_DISABLE;
  if (sigaltstack (&nstk, 0) < 0)
    perror ("sigaltstack");

  sigaltstack (0, &nstk);
  if (~nstk.ss_flags & SS_DISABLE)
    abort ();

  if (~ostk.ss_flags & SS_DISABLE)
    sigaltstack (&ostk, 0);

  sigaction (SIGUSR2, &osa, 0);
  sigprocmask (SIG_SETMASK, &osig, 0);

# elif CORO_LOSER

  coro_setjmp (ctx->env);
  #if __CYGWIN__ && __i386
    ctx->env[8]                        = (long)    coro_init;
    ctx->env[7]                        = (long)    ((char *)sptr + ssize)         - sizeof (long);
  #elif __CYGWIN__ && __x86_64
    ctx->env[7]                        = (long)    coro_init;
    ctx->env[6]                        = (long)    ((char *)sptr + ssize)         - sizeof (long);
  #elif defined(__MINGW32__)
    ctx->env[5]                        = (long)    coro_init;
    ctx->env[4]                        = (long)    ((char *)sptr + ssize)         - sizeof (long);
  #elif defined(_M_IX86)
    ((_JUMP_BUFFER *)&ctx->env)->Eip   = (long)    coro_init;
    ((_JUMP_BUFFER *)&ctx->env)->Esp   = (long)    STACK_ADJUST_PTR (sptr, ssize) - sizeof (long);
  #elif defined(_M_AMD64)
    ((_JUMP_BUFFER *)&ctx->env)->Rip   = (__int64) coro_init;
    ((_JUMP_BUFFER *)&ctx->env)->Rsp   = (__int64) STACK_ADJUST_PTR (sptr, ssize) - sizeof (__int64);
  #elif defined(_M_IA64)
    ((_JUMP_BUFFER *)&ctx->env)->StIIP = (__int64) coro_init;
    ((_JUMP_BUFFER *)&ctx->env)->IntSp = (__int64) STACK_ADJUST_PTR (sptr, ssize) - sizeof (__int64);
  #else
    #error "microsoft libc or architecture not supported"
  #endif

# elif CORO_LINUX

  coro_setjmp (ctx->env);
  #if __GLIBC__ >= 2 && __GLIBC_MINOR__ >= 0 && defined (JB_PC) && defined (JB_SP)
    ctx->env[0].__jmpbuf[JB_PC]        = (long)    coro_init;
    ctx->env[0].__jmpbuf[JB_SP]        = (long)    STACK_ADJUST_PTR (sptr, ssize) - sizeof (long);
  #elif __GLIBC__ >= 2 && __GLIBC_MINOR__ >= 0 && defined (__mc68000__)
    ctx->env[0].__jmpbuf[0].__aregs[0] = (long int)coro_init;
    ctx->env[0].__jmpbuf[0].__sp       = (int *)   ((char *)sptr + ssize)         - sizeof (long);
  #elif defined (__GNU_LIBRARY__) && defined (__i386__)
    ctx->env[0].__jmpbuf[0].__pc       = (char *)  coro_init;
    ctx->env[0].__jmpbuf[0].__sp       = (void *)  ((char *)sptr + ssize)         - sizeof (long);
  #elif defined (__GNU_LIBRARY__) && defined (__amd64__)
    ctx->env[0].__jmpbuf[JB_PC]        = (long)    coro_init;
    ctx->env[0].__jmpbuf[0].__sp       = (void *)  ((char *)sptr + ssize)         - sizeof (long);
  #else
    #error "linux libc or architecture not supported"
  #endif

# elif CORO_IRIX

  coro_setjmp (ctx->env, 0);
  ctx->env[JB_PC]                      = (__uint64_t)coro_init;
  ctx->env[JB_SP]                      = (__uint64_t)STACK_ADJUST_PTR (sptr, ssize) - sizeof (long);

# elif CORO_ASM

  ctx->sp = (void **)(ssize + (char *)sptr);
  *--ctx->sp = (void *)abort; /* needed for alignment only */
  *--ctx->sp = (void *)coro_init;

  #if CORO_WIN_TIB
  *--ctx->sp = 0;                    /* ExceptionList */
  *--ctx->sp = (char *)sptr + ssize; /* StackBase */
  *--ctx->sp = sptr;                 /* StackLimit */
  #endif

  ctx->sp -= NUM_SAVED;
  memset (ctx->sp, 0, sizeof (*ctx->sp) * NUM_SAVED);

# elif CORO_UCONTEXT

  getcontext (&(ctx->uc));

  ctx->uc.uc_link           =  0;
  ctx->uc.uc_stack.ss_sp    = sptr;
  ctx->uc.uc_stack.ss_size  = (size_t)ssize;
  ctx->uc.uc_stack.ss_flags = 0;

  makecontext (&(ctx->uc), (void (*)())coro_init, 0);

# endif

  coro_transfer (create_coro, new_coro);
}

/*****************************************************************************/
/* pthread backend                                                           */
/*****************************************************************************/
#elif CORO_PTHREAD

/* this mutex will be locked by the running coroutine */
pthread_mutex_t coro_mutex = PTHREAD_MUTEX_INITIALIZER;

struct coro_init_args
{
  coro_func func;
  void *arg;
  coro_context *self, *main;
};

static pthread_t null_tid;

/* I'd so love to cast pthread_mutex_unlock to void (*)(void *)... */
static void
mutex_unlock_wrapper (void *arg)
{
  pthread_mutex_unlock ((pthread_mutex_t *)arg);
}

static void *
coro_init (void *args_)
{
  struct coro_init_args *args = (struct coro_init_args *)args_;
  coro_func func = args->func;
  void *arg = args->arg;

  pthread_mutex_lock (&coro_mutex);

  /* we try to be good citizens and use deferred cancellation and cleanup handlers */
  pthread_cleanup_push (mutex_unlock_wrapper, &coro_mutex);
    coro_transfer (args->self, args->main);
    func (arg);
  pthread_cleanup_pop (1);

  return 0;
}

void
coro_transfer (coro_context *prev, coro_context *next)
{
  pthread_cond_signal (&next->cv);
  pthread_cond_wait (&prev->cv, &coro_mutex);
#if __FreeBSD__ /* freebsd is of course broken and needs manual testcancel calls... yay... */
  pthread_testcancel ();
#endif
}

void
coro_create (coro_context *ctx, coro_func coro, void *arg, void *sptr, long ssize)
{
  static coro_context nctx;
  static int once;

  if (!once)
    {
      once = 1;

      pthread_mutex_lock (&coro_mutex);
      pthread_cond_init (&nctx.cv, 0);
      null_tid = pthread_self ();
    }

  pthread_cond_init (&ctx->cv, 0);

  if (coro)
    {
      pthread_attr_t attr;
      struct coro_init_args args;

      args.func = coro;
      args.arg  = arg;
      args.self = ctx;
      args.main = &nctx;

      pthread_attr_init (&attr);
#if __UCLIBC__
      /* exists, but is borked */
      /*pthread_attr_setstacksize (&attr, (size_t)ssize);*/
#else
      pthread_attr_setstack (&attr, sptr, (size_t)ssize);
#endif
      pthread_attr_setscope (&attr, PTHREAD_SCOPE_PROCESS);
      pthread_create (&ctx->id, &attr, coro_init, &args);

      coro_transfer (args.main, args.self);
    }
  else
    ctx->id = null_tid;
}

void
coro_destroy (coro_context *ctx)
{
  if (!pthread_equal (ctx->id, null_tid))
    {
      pthread_cancel (ctx->id);
      pthread_mutex_unlock (&coro_mutex);
      pthread_join (ctx->id, 0);
      pthread_mutex_lock (&coro_mutex);
    }

  pthread_cond_destroy (&ctx->cv);
}

#else
# error unsupported backend
#endif

Revision:	1.58
Committed:	Fri Jun 10 12:27:02 2011 UTC (12 years, 11 months ago) by root
Content type:	text/plain
Branch:	MAIN
Changes since 1.57:	+55 -33 lines
Log Message:	* empty log message *
#	User	Rev	Content
1	root	1.1	/*
2	root	1.56	* Copyright (c) 2001-2011 Marc Alexander Lehmann <schmorp@schmorp.de>
3	root	1.1	*
4			* Redistribution and use in source and binary forms, with or without modifica-
5			* tion, are permitted provided that the following conditions are met:
6			*
7			* 1. Redistributions of source code must retain the above copyright notice,
8			* this list of conditions and the following disclaimer.
9			*
10			* 2. Redistributions in binary form must reproduce the above copyright
11			* notice, this list of conditions and the following disclaimer in the
12			* documentation and/or other materials provided with the distribution.
13			*
14			* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
15			* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER-
16			* CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
17			* EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE-
18			* CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19			* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
20			* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
21			* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH-
22			* ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
23			* OF THE POSSIBILITY OF SUCH DAMAGE.
24			*
25	root	1.29	* Alternatively, the contents of this file may be used under the terms of
26			* the GNU General Public License ("GPL") version 2 or any later version,
27			* in which case the provisions of the GPL are applicable instead of
28			* the above. If you wish to allow the use of your version of this file
29			* only under the terms of the GPL and not to allow others to use your
30			* version of this file under the BSD license, indicate your decision
31			* by deleting the provisions above and replace them with the notice
32			* and other provisions required by the GPL. If you do not delete the
33			* provisions above, a recipient may use your version of this file under
34			* either the BSD or the GPL.
35			*
36	root	1.1	* This library is modelled strictly after Ralf S. Engelschalls article at
37	root	1.29	* http://www.gnu.org/software/pth/rse-pmt.ps. So most of the credit must
38	root	1.1	* go to Ralf S. Engelschall <rse@engelschall.com>.
39			*/
40
41			#include "coro.h"
42
43	root	1.38	#include <string.h>
44
45	root	1.39	/*****************************************************************************/
46			/* ucontext/setjmp/asm backends */
47			/*****************************************************************************/
48			#if CORO_UCONTEXT \|\| CORO_SJLJ \|\| CORO_LOSER \|\| CORO_LINUX \|\| CORO_IRIX \|\| CORO_ASM
49
50			# if CORO_UCONTEXT
51			# include <stddef.h>
52			# endif
53
54			# if !defined(STACK_ADJUST_PTR)
55			# if __sgi
56	root	1.5	/* IRIX is decidedly NON-unix */
57	root	1.39	# define STACK_ADJUST_PTR(sp,ss) ((char *)(sp) + (ss) - 8)
58			# define STACK_ADJUST_SIZE(sp,ss) ((ss) - 8)
59			# elif (__i386__ && CORO_LINUX) \|\| (_M_IX86 && CORO_LOSER)
60			# define STACK_ADJUST_PTR(sp,ss) ((char *)(sp) + (ss))
61			# define STACK_ADJUST_SIZE(sp,ss) (ss)
62			# elif (__amd64__ && CORO_LINUX) \|\| ((_M_AMD64 \|\| _M_IA64) && CORO_LOSER)
63			# define STACK_ADJUST_PTR(sp,ss) ((char *)(sp) + (ss) - 8)
64			# define STACK_ADJUST_SIZE(sp,ss) (ss)
65			# else
66			# define STACK_ADJUST_PTR(sp,ss) (sp)
67			# define STACK_ADJUST_SIZE(sp,ss) (ss)
68			# endif
69	root	1.8	# endif
70	root	1.1
71	root	1.38	# include <stdlib.h>
72	root	1.17
73	root	1.38	# if CORO_SJLJ
74			# include <stdio.h>
75			# include <signal.h>
76			# include <unistd.h>
77			# endif
78	root	1.1
79	root	1.40	static coro_func coro_init_func;
80			static void *coro_init_arg;
81			static coro_context new_coro, create_coro;
82	root	1.1
83			static void
84			coro_init (void)
85			{
86			volatile coro_func func = coro_init_func;
87			volatile void *arg = coro_init_arg;
88
89	root	1.40	coro_transfer (new_coro, create_coro);
90	root	1.1
91	root	1.57	#if __linux && __amd64
92			/* we blindly assume on any __linux with __amd64 we have a new enough gas with .cfi_undefined support */
93	root	1.56	asm (".cfi_undefined rip");
94			#endif
95
96	root	1.3	func ((void *)arg);
97	root	1.1
98			/* the new coro returned. bad. just abort() for now */
99			abort ();
100			}
101
102			# if CORO_SJLJ
103
104	root	1.39	static volatile int trampoline_done;
105	root	1.1
106			/* trampoline signal handler */
107			static void
108	root	1.14	trampoline (int sig)
109	root	1.1	{
110	root	1.44	if (coro_setjmp (new_coro->env))
111			coro_init (); /* start it */
112	root	1.1	else
113	root	1.39	trampoline_done = 1;
114	root	1.1	}
115
116			# endif
117
118	root	1.39	# if CORO_ASM
119	root	1.38
120			asm (
121			".text\n"
122			".globl coro_transfer\n"
123			".type coro_transfer, @function\n"
124			"coro_transfer:\n"
125	root	1.52	/* windows, of course, gives a shit on the amd64 ABI and uses different registers */
126			/* http://blogs.msdn.com/freik/archive/2005/03/17/398200.aspx */
127	root	1.39	#if __amd64
128	root	1.58	#ifdef _WIN32
129			#define NUM_SAVED 8
130			"\tpush %rsi\n"
131			"\tpush %rdi\n"
132			"\tpush %rbp\n"
133			"\tpush %rbx\n"
134			"\tpush %r12\n"
135			"\tpush %r13\n"
136			"\tpush %r14\n"
137			"\tpush %r15\n"
138			#if CORO_WIN_TIB
139			"\tpush %gs:0x0\n"
140			"\tpush %gs:0x8\n"
141			"\tpush %gs:0xc\n"
142			#endif
143			"\tmov %rsp, (%rcx)\n"
144			"\tmov (%rdx), %rsp\n"
145			#if CORO_WIN_TIB
146			"\tpop %gs:0xc\n"
147			"\tpop %gs:0x8\n"
148			"\tpop %gs:0x0\n"
149			#endif
150			"\tpop %r15\n"
151			"\tpop %r14\n"
152			"\tpop %r13\n"
153			"\tpop %r12\n"
154			"\tpop %rbx\n"
155			"\tpop %rbp\n"
156			"\tpop %rdi\n"
157			"\tpop %rsi\n"
158			#else
159			#define NUM_SAVED 6
160			"\tpush %rbp\n"
161			"\tpush %rbx\n"
162			"\tpush %r12\n"
163			"\tpush %r13\n"
164			"\tpush %r14\n"
165			"\tpush %r15\n"
166			"\tmov %rsp, (%rdi)\n"
167			"\tmov (%rsi), %rsp\n"
168			"\tpop %r15\n"
169			"\tpop %r14\n"
170			"\tpop %r13\n"
171			"\tpop %r12\n"
172			"\tpop %rbx\n"
173			"\tpop %rbp\n"
174	root	1.50	#endif
175	root	1.39	#elif __i386
176	root	1.50	#define NUM_SAVED 4
177	root	1.39	"\tpush %ebp\n"
178			"\tpush %ebx\n"
179			"\tpush %esi\n"
180			"\tpush %edi\n"
181	root	1.50	#if CORO_WIN_TIB
182	root	1.51	"\tpush %fs:0\n"
183			"\tpush %fs:4\n"
184	root	1.50	"\tpush %fs:8\n"
185			#endif
186	root	1.58	"\tmov %esp, (%eax)\n"
187			"\tmov (%edx), %esp\n"
188	root	1.50	#if CORO_WIN_TIB
189	root	1.58	"\tpop %fs:8\n"
190			"\tpop %fs:4\n"
191			"\tpop %fs:0\n"
192	root	1.50	#endif
193	root	1.58	"\tpop %edi\n"
194			"\tpop %esi\n"
195			"\tpop %ebx\n"
196			"\tpop %ebp\n"
197	root	1.39	#else
198			#error unsupported architecture
199			#endif
200	root	1.38	"\tret\n"
201			);
202
203	root	1.39	# endif
204	root	1.38
205			void
206			coro_create (coro_context ctx, coro_func coro, void arg, void *sptr, long ssize)
207	root	1.1	{
208	root	1.39	coro_context nctx;
209	root	1.1	# if CORO_SJLJ
210			stack_t ostk, nstk;
211			struct sigaction osa, nsa;
212			sigset_t nsig, osig;
213			# endif
214
215	root	1.38	if (!coro)
216			return;
217
218	root	1.1	coro_init_func = coro;
219			coro_init_arg = arg;
220
221			new_coro = ctx;
222			create_coro = &nctx;
223
224			# if CORO_SJLJ
225			/* we use SIGUSR2. first block it, then fiddle with it. */
226
227			sigemptyset (&nsig);
228			sigaddset (&nsig, SIGUSR2);
229			sigprocmask (SIG_BLOCK, &nsig, &osig);
230
231			nsa.sa_handler = trampoline;
232			sigemptyset (&nsa.sa_mask);
233			nsa.sa_flags = SA_ONSTACK;
234
235			if (sigaction (SIGUSR2, &nsa, &osa))
236	root	1.23	{
237			perror ("sigaction");
238			abort ();
239			}
240	root	1.1
241			/* set the new stack */
242	root	1.54	nstk.ss_sp = STACK_ADJUST_PTR (sptr, ssize); /* yes, some platforms (IRIX) get this wrong. */
243			nstk.ss_size = STACK_ADJUST_SIZE (sptr, ssize);
244	root	1.1	nstk.ss_flags = 0;
245
246			if (sigaltstack (&nstk, &ostk) < 0)
247	root	1.23	{
248			perror ("sigaltstack");
249			abort ();
250			}
251	root	1.1
252	root	1.39	trampoline_done = 0;
253	root	1.1	kill (getpid (), SIGUSR2);
254			sigfillset (&nsig); sigdelset (&nsig, SIGUSR2);
255
256	root	1.39	while (!trampoline_done)
257	root	1.1	sigsuspend (&nsig);
258
259			sigaltstack (0, &nstk);
260			nstk.ss_flags = SS_DISABLE;
261			if (sigaltstack (&nstk, 0) < 0)
262			perror ("sigaltstack");
263
264			sigaltstack (0, &nstk);
265			if (~nstk.ss_flags & SS_DISABLE)
266			abort ();
267
268			if (~ostk.ss_flags & SS_DISABLE)
269			sigaltstack (&ostk, 0);
270
271	root	1.19	sigaction (SIGUSR2, &osa, 0);
272	root	1.1	sigprocmask (SIG_SETMASK, &osig, 0);
273
274	root	1.16	# elif CORO_LOSER
275	root	1.1
276	root	1.44	coro_setjmp (ctx->env);
277	root	1.48	#if __CYGWIN__ && __i386
278	root	1.47	ctx->env[8] = (long) coro_init;
279			ctx->env[7] = (long) ((char *)sptr + ssize) - sizeof (long);
280	root	1.48	#elif __CYGWIN__ && __x86_64
281			ctx->env[7] = (long) coro_init;
282			ctx->env[6] = (long) ((char *)sptr + ssize) - sizeof (long);
283	root	1.45	#elif defined(__MINGW32__)
284	root	1.47	ctx->env[5] = (long) coro_init;
285			ctx->env[4] = (long) ((char *)sptr + ssize) - sizeof (long);
286	root	1.39	#elif defined(_M_IX86)
287	root	1.47	((_JUMP_BUFFER *)&ctx->env)->Eip = (long) coro_init;
288			((_JUMP_BUFFER *)&ctx->env)->Esp = (long) STACK_ADJUST_PTR (sptr, ssize) - sizeof (long);
289	root	1.39	#elif defined(_M_AMD64)
290	root	1.47	((_JUMP_BUFFER *)&ctx->env)->Rip = (__int64) coro_init;
291	root	1.48	((_JUMP_BUFFER *)&ctx->env)->Rsp = (__int64) STACK_ADJUST_PTR (sptr, ssize) - sizeof (__int64);
292	root	1.39	#elif defined(_M_IA64)
293	root	1.47	((_JUMP_BUFFER *)&ctx->env)->StIIP = (__int64) coro_init;
294	root	1.48	((_JUMP_BUFFER *)&ctx->env)->IntSp = (__int64) STACK_ADJUST_PTR (sptr, ssize) - sizeof (__int64);
295	root	1.39	#else
296			#error "microsoft libc or architecture not supported"
297			#endif
298	root	1.4
299			# elif CORO_LINUX
300
301	root	1.44	coro_setjmp (ctx->env);
302	root	1.39	#if __GLIBC__ >= 2 && __GLIBC_MINOR__ >= 0 && defined (JB_PC) && defined (JB_SP)
303	root	1.47	ctx->env[0].__jmpbuf[JB_PC] = (long) coro_init;
304			ctx->env[0].__jmpbuf[JB_SP] = (long) STACK_ADJUST_PTR (sptr, ssize) - sizeof (long);
305	root	1.39	#elif __GLIBC__ >= 2 && __GLIBC_MINOR__ >= 0 && defined (__mc68000__)
306			ctx->env[0].__jmpbuf[0].__aregs[0] = (long int)coro_init;
307	root	1.47	ctx->env[0].__jmpbuf[0].__sp = (int ) ((char )sptr + ssize) - sizeof (long);
308	root	1.39	#elif defined (__GNU_LIBRARY__) && defined (__i386__)
309	root	1.47	ctx->env[0].__jmpbuf[0].__pc = (char *) coro_init;
310			ctx->env[0].__jmpbuf[0].__sp = (void ) ((char )sptr + ssize) - sizeof (long);
311	root	1.39	#elif defined (__GNU_LIBRARY__) && defined (__amd64__)
312	root	1.47	ctx->env[0].__jmpbuf[JB_PC] = (long) coro_init;
313			ctx->env[0].__jmpbuf[0].__sp = (void ) ((char )sptr + ssize) - sizeof (long);
314	root	1.39	#else
315			#error "linux libc or architecture not supported"
316			#endif
317	root	1.5
318			# elif CORO_IRIX
319
320	root	1.44	coro_setjmp (ctx->env, 0);
321	root	1.47	ctx->env[JB_PC] = (__uint64_t)coro_init;
322			ctx->env[JB_SP] = (__uint64_t)STACK_ADJUST_PTR (sptr, ssize) - sizeof (long);
323	root	1.1
324	root	1.27	# elif CORO_ASM
325
326	root	1.41	ctx->sp = (void *)(ssize + (char )sptr);
327	root	1.37	--ctx->sp = (void )abort; /* needed for alignment only */
328	root	1.27	--ctx->sp = (void )coro_init;
329
330	root	1.50	#if CORO_WIN_TIB
331	root	1.51	--ctx->sp = 0; / ExceptionList */
332			--ctx->sp = (char )sptr + ssize; /* StackBase */
333	root	1.50	--ctx->sp = sptr; / StackLimit */
334			#endif
335
336	root	1.51	ctx->sp -= NUM_SAVED;
337	root	1.55	memset (ctx->sp, 0, sizeof (ctx->sp) NUM_SAVED);
338	root	1.51
339	root	1.39	# elif CORO_UCONTEXT
340
341			getcontext (&(ctx->uc));
342
343			ctx->uc.uc_link = 0;
344			ctx->uc.uc_stack.ss_sp = sptr;
345			ctx->uc.uc_stack.ss_size = (size_t)ssize;
346			ctx->uc.uc_stack.ss_flags = 0;
347
348			makecontext (&(ctx->uc), (void (*)())coro_init, 0);
349
350	root	1.1	# endif
351
352	root	1.39	coro_transfer (create_coro, new_coro);
353			}
354
355			/*****************************************************************************/
356			/* pthread backend */
357			/*****************************************************************************/
358	root	1.40	#elif CORO_PTHREAD
359	root	1.1
360	root	1.39	/* this mutex will be locked by the running coroutine */
361			pthread_mutex_t coro_mutex = PTHREAD_MUTEX_INITIALIZER;
362	root	1.30
363	root	1.39	struct coro_init_args
364			{
365			coro_func func;
366			void *arg;
367			coro_context self, main;
368			};
369
370			static pthread_t null_tid;
371
372			/* I'd so love to cast pthread_mutex_unlock to void ()(void )... */
373			static void
374			mutex_unlock_wrapper (void *arg)
375			{
376			pthread_mutex_unlock ((pthread_mutex_t *)arg);
377			}
378
379			static void *
380			coro_init (void *args_)
381			{
382			struct coro_init_args args = (struct coro_init_args )args_;
383			coro_func func = args->func;
384			void *arg = args->arg;
385
386			pthread_mutex_lock (&coro_mutex);
387
388			/* we try to be good citizens and use deferred cancellation and cleanup handlers */
389			pthread_cleanup_push (mutex_unlock_wrapper, &coro_mutex);
390			coro_transfer (args->self, args->main);
391			func (arg);
392			pthread_cleanup_pop (1);
393
394			return 0;
395			}
396
397			void
398			coro_transfer (coro_context prev, coro_context next)
399			{
400			pthread_cond_signal (&next->cv);
401			pthread_cond_wait (&prev->cv, &coro_mutex);
402	root	1.43	#if __FreeBSD__ /* freebsd is of course broken and needs manual testcancel calls... yay... */
403			pthread_testcancel ();
404			#endif
405	root	1.39	}
406
407			void
408			coro_create (coro_context ctx, coro_func coro, void arg, void *sptr, long ssize)
409			{
410	root	1.38	static coro_context nctx;
411	root	1.30	static int once;
412
413			if (!once)
414			{
415	root	1.38	once = 1;
416
417	root	1.30	pthread_mutex_lock (&coro_mutex);
418	root	1.38	pthread_cond_init (&nctx.cv, 0);
419			null_tid = pthread_self ();
420	root	1.30	}
421
422	root	1.38	pthread_cond_init (&ctx->cv, 0);
423	root	1.30
424	root	1.38	if (coro)
425			{
426			pthread_attr_t attr;
427			struct coro_init_args args;
428
429			args.func = coro;
430			args.arg = arg;
431			args.self = ctx;
432			args.main = &nctx;
433
434			pthread_attr_init (&attr);
435	root	1.53	#if __UCLIBC__
436	root	1.54	/* exists, but is borked */
437			/pthread_attr_setstacksize (&attr, (size_t)ssize);/
438	root	1.53	#else
439	root	1.38	pthread_attr_setstack (&attr, sptr, (size_t)ssize);
440	root	1.53	#endif
441	root	1.38	pthread_attr_setscope (&attr, PTHREAD_SCOPE_PROCESS);
442	root	1.39	pthread_create (&ctx->id, &attr, coro_init, &args);
443	root	1.38
444			coro_transfer (args.main, args.self);
445			}
446			else
447			ctx->id = null_tid;
448	root	1.39	}
449
450			void
451			coro_destroy (coro_context *ctx)
452			{
453			if (!pthread_equal (ctx->id, null_tid))
454			{
455			pthread_cancel (ctx->id);
456			pthread_mutex_unlock (&coro_mutex);
457			pthread_join (ctx->id, 0);
458			pthread_mutex_lock (&coro_mutex);
459			}
460
461			pthread_cond_destroy (&ctx->cv);
462			}
463	root	1.30
464	root	1.40	#else
465			# error unsupported backend
466	root	1.1	#endif
467