libcoro/coro.c

/*
 * Copyright (c) 2001-2008 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>

#if !defined(STACK_ADJUST_PTR)
/* IRIX is decidedly NON-unix */
# if __sgi
#  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

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

#if CORO_SJLJ || CORO_LOSER || CORO_LINUX || CORO_IRIX || CORO_ASM

# include <stdlib.h>

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

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

/* what we really want to detect here is wether we use a new-enough version of GAS */
/* instead, check for gcc 3, ELF and GNU/Linux and hope for the best */
# if __GNUC__ >= 3 && __ELF__ && __linux__
#  define HAVE_CFI 1
# endif

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

  coro_transfer ((coro_context *)new_coro, (coro_context *)create_coro);

  func ((void *)arg);

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

# if CORO_SJLJ

static volatile int trampoline_count;

/* trampoline signal handler */
static void
trampoline (int sig)
{
  if (setjmp (((coro_context *)new_coro)->env))
    {
#  if HAVE_CFI
      asm (".cfi_startproc");
#  endif
      coro_init (); /* start it */
#  if HAVE_CFI
      asm (".cfi_endproc");
#  endif
    }
  else
    trampoline_count++;
}

# endif

#endif

#if CORO_ASM

  asm (
       ".text\n"
       ".globl coro_transfer\n"
       ".type coro_transfer, @function\n"
       "coro_transfer:\n"
# if __amd64
#  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"
# elif __i386
#  define NUM_SAVED 4
       "\tpush %ebp\n"
       "\tpush %ebx\n"
       "\tpush %esi\n"
       "\tpush %edi\n"
       "\tmov  %esp, (%eax)\n"
       "\tmov  (%edx), %esp\n"
       "\tpop  %edi\n"
       "\tpop  %esi\n"
       "\tpop  %ebx\n"
       "\tpop  %ebp\n"
# else
#  error unsupported architecture
# endif
       "\tret\n"
  );

#endif

#if 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 *
trampoline (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);
}

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);
}

#endif

/* initialize a machine state */
void
coro_create (coro_context *ctx, coro_func coro, void *arg, void *sptr, long ssize)
{
#if CORO_UCONTEXT

  if (!coro)
    return;

  getcontext (&(ctx->uc));

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

  makecontext (&(ctx->uc), (void (*)())coro, 1, arg);

#elif CORO_SJLJ || CORO_LOSER || CORO_LINUX || CORO_IRIX || CORO_ASM

# if CORO_SJLJ
  stack_t ostk, nstk;
  struct sigaction osa, nsa;
  sigset_t nsig, osig;
# endif
  coro_context nctx;

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

  while (!trampoline_count)
    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

  setjmp (ctx->env);
#if __CYGWIN__
  ctx->env[7] = (long)((char *)sptr + ssize) - sizeof (long);
  ctx->env[8] = (long)coro_init;
#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 (long);
#elif defined(_M_IA64)
  ((_JUMP_BUFFER *)&ctx->env)->StIIP = (__int64)coro_init;
  ((_JUMP_BUFFER *)&ctx->env)->IntSp = (__int64)STACK_ADJUST_PTR (sptr, ssize) - sizeof (long);
#else
# error "microsoft libc or architecture not supported"
#endif

# elif CORO_LINUX

  _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

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

# endif

  coro_transfer ((coro_context *)create_coro, (coro_context *)new_coro);

# elif CORO_PTHREAD

  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);
      pthread_attr_setstack (&attr, sptr, (size_t)ssize);
      pthread_attr_setscope (&attr, PTHREAD_SCOPE_PROCESS);
      pthread_create (&ctx->id, &attr, trampoline, &args);

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

#else
# error unsupported backend
#endif
}

Revision:	1.38
Committed:	Fri Nov 7 20:12:26 2008 UTC (15 years, 6 months ago) by root
Content type:	text/plain
Branch:	MAIN
Changes since 1.37:	+125 -83 lines
Log Message:	* empty log message *
#	User	Rev	Content
1	root	1.1	/*
2	root	1.28	* Copyright (c) 2001-2008 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	1.8	#if !defined(STACK_ADJUST_PTR)
46	root	1.5	/* IRIX is decidedly NON-unix */
47	root	1.8	# if __sgi
48			# define STACK_ADJUST_PTR(sp,ss) ((char *)(sp) + (ss) - 8)
49			# define STACK_ADJUST_SIZE(sp,ss) ((ss) - 8)
50	root	1.31	# elif (__i386__ && CORO_LINUX) \|\| (_M_IX86 && CORO_LOSER)
51	root	1.8	# define STACK_ADJUST_PTR(sp,ss) ((char *)(sp) + (ss))
52			# define STACK_ADJUST_SIZE(sp,ss) (ss)
53	root	1.31	# elif (__amd64__ && CORO_LINUX) \|\| ((_M_AMD64 \|\| _M_IA64) && CORO_LOSER)
54	root	1.18	# define STACK_ADJUST_PTR(sp,ss) ((char *)(sp) + (ss) - 8)
55			# define STACK_ADJUST_SIZE(sp,ss) (ss)
56	root	1.8	# else
57			# define STACK_ADJUST_PTR(sp,ss) (sp)
58			# define STACK_ADJUST_SIZE(sp,ss) (ss)
59			# endif
60	root	1.5	#endif
61	root	1.7
62	root	1.20	#if CORO_UCONTEXT
63			# include <stddef.h>
64			#endif
65
66	root	1.27	#if CORO_SJLJ \|\| CORO_LOSER \|\| CORO_LINUX \|\| CORO_IRIX \|\| CORO_ASM
67	root	1.1
68	root	1.38	# include <stdlib.h>
69	root	1.17
70	root	1.38	# if CORO_SJLJ
71			# include <stdio.h>
72			# include <signal.h>
73			# include <unistd.h>
74			# endif
75	root	1.1
76			static volatile coro_func coro_init_func;
77			static volatile void *coro_init_arg;
78			static volatile coro_context new_coro, create_coro;
79
80	root	1.25	/* what we really want to detect here is wether we use a new-enough version of GAS */
81	root	1.28	/* instead, check for gcc 3, ELF and GNU/Linux and hope for the best */
82	root	1.38	# if __GNUC__ >= 3 && __ELF__ && __linux__
83			# define HAVE_CFI 1
84			# endif
85	root	1.25
86	root	1.1	static void
87			coro_init (void)
88			{
89			volatile coro_func func = coro_init_func;
90			volatile void *arg = coro_init_arg;
91
92	root	1.2	coro_transfer ((coro_context )new_coro, (coro_context )create_coro);
93	root	1.1
94	root	1.3	func ((void *)arg);
95	root	1.1
96			/* the new coro returned. bad. just abort() for now */
97			abort ();
98			}
99
100			# if CORO_SJLJ
101
102			static volatile int trampoline_count;
103
104			/* trampoline signal handler */
105			static void
106	root	1.14	trampoline (int sig)
107	root	1.1	{
108	root	1.3	if (setjmp (((coro_context *)new_coro)->env))
109	root	1.26	{
110	root	1.38	# if HAVE_CFI
111	root	1.26	asm (".cfi_startproc");
112	root	1.38	# endif
113	root	1.26	coro_init (); /* start it */
114	root	1.38	# if HAVE_CFI
115	root	1.26	asm (".cfi_endproc");
116	root	1.38	# endif
117	root	1.26	}
118	root	1.1	else
119			trampoline_count++;
120			}
121
122			# endif
123
124			#endif
125
126	root	1.27	#if CORO_ASM
127	root	1.38
128			asm (
129			".text\n"
130			".globl coro_transfer\n"
131			".type coro_transfer, @function\n"
132			"coro_transfer:\n"
133			# if __amd64
134			# define NUM_SAVED 6
135			"\tpush %rbp\n"
136			"\tpush %rbx\n"
137			"\tpush %r12\n"
138			"\tpush %r13\n"
139			"\tpush %r14\n"
140			"\tpush %r15\n"
141			"\tmov %rsp, (%rdi)\n"
142			"\tmov (%rsi), %rsp\n"
143			"\tpop %r15\n"
144			"\tpop %r14\n"
145			"\tpop %r13\n"
146			"\tpop %r12\n"
147			"\tpop %rbx\n"
148			"\tpop %rbp\n"
149			# elif __i386
150			# define NUM_SAVED 4
151			"\tpush %ebp\n"
152			"\tpush %ebx\n"
153			"\tpush %esi\n"
154			"\tpush %edi\n"
155			"\tmov %esp, (%eax)\n"
156			"\tmov (%edx), %esp\n"
157			"\tpop %edi\n"
158			"\tpop %esi\n"
159			"\tpop %ebx\n"
160			"\tpop %ebp\n"
161			# else
162			# error unsupported architecture
163			# endif
164			"\tret\n"
165			);
166
167	root	1.27	#endif
168
169	root	1.30	#if CORO_PTHREAD
170
171	root	1.38	/* this mutex will be locked by the running coroutine */
172			pthread_mutex_t coro_mutex = PTHREAD_MUTEX_INITIALIZER;
173
174			struct coro_init_args
175			{
176	root	1.30	coro_func func;
177			void *arg;
178			coro_context self, main;
179			};
180
181	root	1.38	static pthread_t null_tid;
182
183			/* I'd so love to cast pthread_mutex_unlock to void ()(void )... */
184			static void
185			mutex_unlock_wrapper (void *arg)
186			{
187			pthread_mutex_unlock ((pthread_mutex_t *)arg);
188			}
189	root	1.30
190			static void *
191			trampoline (void *args_)
192			{
193			struct coro_init_args args = (struct coro_init_args )args_;
194			coro_func func = args->func;
195			void *arg = args->arg;
196
197			pthread_mutex_lock (&coro_mutex);
198	root	1.38
199			/* we try to be good citizens and use deferred cancellation and cleanup handlers */
200			pthread_cleanup_push (mutex_unlock_wrapper, &coro_mutex);
201			coro_transfer (args->self, args->main);
202			func (arg);
203			pthread_cleanup_pop (1);
204	root	1.30
205			return 0;
206			}
207
208	root	1.38	void
209			coro_transfer (coro_context prev, coro_context next)
210			{
211			pthread_cond_signal (&next->cv);
212			pthread_cond_wait (&prev->cv, &coro_mutex);
213			}
214	root	1.35
215	root	1.38	void
216			coro_destroy (coro_context *ctx)
217	root	1.30	{
218	root	1.38	if (!pthread_equal (ctx->id, null_tid))
219			{
220			pthread_cancel (ctx->id);
221			pthread_mutex_unlock (&coro_mutex);
222			pthread_join (ctx->id, 0);
223			pthread_mutex_lock (&coro_mutex);
224			}
225
226			pthread_cond_destroy (&ctx->cv);
227	root	1.30	}
228
229			#endif
230
231	root	1.1	/* initialize a machine state */
232	root	1.38	void
233			coro_create (coro_context ctx, coro_func coro, void arg, void *sptr, long ssize)
234	root	1.1	{
235			#if CORO_UCONTEXT
236
237	root	1.38	if (!coro)
238			return;
239
240	root	1.1	getcontext (&(ctx->uc));
241
242	root	1.5	ctx->uc.uc_link = 0;
243	root	1.9	ctx->uc.uc_stack.ss_sp = STACK_ADJUST_PTR (sptr,ssize);
244	root	1.36	ctx->uc.uc_stack.ss_size = (size_t)STACK_ADJUST_SIZE (sptr,ssize);
245	root	1.1	ctx->uc.uc_stack.ss_flags = 0;
246
247	root	1.38	makecontext (&(ctx->uc), (void (*)())coro, 1, arg);
248	root	1.1
249	root	1.27	#elif CORO_SJLJ \|\| CORO_LOSER \|\| CORO_LINUX \|\| CORO_IRIX \|\| CORO_ASM
250	root	1.1
251			# if CORO_SJLJ
252			stack_t ostk, nstk;
253			struct sigaction osa, nsa;
254			sigset_t nsig, osig;
255			# endif
256			coro_context nctx;
257
258	root	1.38	if (!coro)
259			return;
260
261	root	1.1	coro_init_func = coro;
262			coro_init_arg = arg;
263
264			new_coro = ctx;
265			create_coro = &nctx;
266
267			# if CORO_SJLJ
268			/* we use SIGUSR2. first block it, then fiddle with it. */
269
270			sigemptyset (&nsig);
271			sigaddset (&nsig, SIGUSR2);
272			sigprocmask (SIG_BLOCK, &nsig, &osig);
273
274			nsa.sa_handler = trampoline;
275			sigemptyset (&nsa.sa_mask);
276			nsa.sa_flags = SA_ONSTACK;
277
278			if (sigaction (SIGUSR2, &nsa, &osa))
279	root	1.23	{
280			perror ("sigaction");
281			abort ();
282			}
283	root	1.1
284			/* set the new stack */
285	root	1.9	nstk.ss_sp = STACK_ADJUST_PTR (sptr,ssize); /* yes, some platforms (IRIX) get this wrong. */
286	root	1.8	nstk.ss_size = STACK_ADJUST_SIZE (sptr,ssize);
287	root	1.1	nstk.ss_flags = 0;
288
289			if (sigaltstack (&nstk, &ostk) < 0)
290	root	1.23	{
291			perror ("sigaltstack");
292			abort ();
293			}
294	root	1.1
295			trampoline_count = 0;
296			kill (getpid (), SIGUSR2);
297			sigfillset (&nsig); sigdelset (&nsig, SIGUSR2);
298
299			while (!trampoline_count)
300			sigsuspend (&nsig);
301
302			sigaltstack (0, &nstk);
303			nstk.ss_flags = SS_DISABLE;
304			if (sigaltstack (&nstk, 0) < 0)
305			perror ("sigaltstack");
306
307			sigaltstack (0, &nstk);
308			if (~nstk.ss_flags & SS_DISABLE)
309			abort ();
310
311			if (~ostk.ss_flags & SS_DISABLE)
312			sigaltstack (&ostk, 0);
313
314	root	1.19	sigaction (SIGUSR2, &osa, 0);
315	root	1.1
316			sigprocmask (SIG_SETMASK, &osig, 0);
317
318	root	1.16	# elif CORO_LOSER
319	root	1.1
320	root	1.4	setjmp (ctx->env);
321	root	1.21	#if __CYGWIN__
322	root	1.36	ctx->env[7] = (long)((char *)sptr + ssize) - sizeof (long);
323	pcg	1.11	ctx->env[8] = (long)coro_init;
324	root	1.21	#elif defined(_M_IX86)
325			((_JUMP_BUFFER *)&ctx->env)->Eip = (long)coro_init;
326	root	1.36	((_JUMP_BUFFER *)&ctx->env)->Esp = (long)STACK_ADJUST_PTR (sptr, ssize) - sizeof (long);
327	root	1.21	#elif defined(_M_AMD64)
328			((_JUMP_BUFFER *)&ctx->env)->Rip = (__int64)coro_init;
329	root	1.36	((_JUMP_BUFFER *)&ctx->env)->Rsp = (__int64)STACK_ADJUST_PTR (sptr, ssize) - sizeof (long);
330	root	1.21	#elif defined(_M_IA64)
331			((_JUMP_BUFFER *)&ctx->env)->StIIP = (__int64)coro_init;
332	root	1.36	((_JUMP_BUFFER *)&ctx->env)->IntSp = (__int64)STACK_ADJUST_PTR (sptr, ssize) - sizeof (long);
333	root	1.21	#else
334	root	1.30	# error "microsoft libc or architecture not supported"
335	root	1.21	#endif
336	root	1.4
337			# elif CORO_LINUX
338
339	root	1.22	_setjmp (ctx->env);
340	root	1.24	#if __GLIBC__ >= 2 && __GLIBC_MINOR__ >= 0 && defined (JB_PC) && defined (JB_SP)
341	root	1.10	ctx->env[0].__jmpbuf[JB_PC] = (long)coro_init;
342	root	1.36	ctx->env[0].__jmpbuf[JB_SP] = (long)STACK_ADJUST_PTR (sptr, ssize) - sizeof (long);
343	root	1.24	#elif __GLIBC__ >= 2 && __GLIBC_MINOR__ >= 0 && defined (__mc68000__)
344	root	1.4	ctx->env[0].__jmpbuf[0].__aregs[0] = (long int)coro_init;
345	root	1.36	ctx->env[0].__jmpbuf[0].__sp = (int )((char )sptr + ssize) - sizeof (long);
346	root	1.24	#elif defined (__GNU_LIBRARY__) && defined (__i386__)
347	root	1.4	ctx->env[0].__jmpbuf[0].__pc = (char *)coro_init;
348	root	1.36	ctx->env[0].__jmpbuf[0].__sp = (void )((char )sptr + ssize) - sizeof (long);
349	root	1.24	#elif defined (__GNU_LIBRARY__) && defined (__amd64__)
350	root	1.12	ctx->env[0].__jmpbuf[JB_PC] = (long)coro_init;
351	root	1.36	ctx->env[0].__jmpbuf[0].__sp = (void )((char )sptr + ssize) - sizeof (long);
352	root	1.4	#else
353	root	1.27	# error "linux libc or architecture not supported"
354	root	1.4	#endif
355	root	1.5
356			# elif CORO_IRIX
357
358			setjmp (ctx->env);
359	root	1.6	ctx->env[JB_PC] = (__uint64_t)coro_init;
360	root	1.36	ctx->env[JB_SP] = (__uint64_t)STACK_ADJUST_PTR (sptr, ssize) - sizeof (long);
361	root	1.1
362	root	1.27	# elif CORO_ASM
363
364			ctx->sp = (volatile void *)(ssize + (char )sptr);
365	root	1.37	--ctx->sp = (void )abort; /* needed for alignment only */
366	root	1.27	--ctx->sp = (void )coro_init;
367	root	1.36	ctx->sp -= NUM_SAVED;
368	root	1.27
369	root	1.1	# endif
370
371	root	1.2	coro_transfer ((coro_context )create_coro, (coro_context )new_coro);
372	root	1.1
373	root	1.30	# elif CORO_PTHREAD
374
375	root	1.38	static coro_context nctx;
376	root	1.30	static int once;
377
378			if (!once)
379			{
380	root	1.38	once = 1;
381
382	root	1.30	pthread_mutex_lock (&coro_mutex);
383	root	1.38	pthread_cond_init (&nctx.cv, 0);
384			null_tid = pthread_self ();
385	root	1.30	}
386
387	root	1.38	pthread_cond_init (&ctx->cv, 0);
388	root	1.30
389	root	1.38	if (coro)
390			{
391			pthread_attr_t attr;
392			struct coro_init_args args;
393
394			args.func = coro;
395			args.arg = arg;
396			args.self = ctx;
397			args.main = &nctx;
398
399			pthread_attr_init (&attr);
400			pthread_attr_setstack (&attr, sptr, (size_t)ssize);
401			pthread_attr_setscope (&attr, PTHREAD_SCOPE_PROCESS);
402			pthread_create (&ctx->id, &attr, trampoline, &args);
403
404			coro_transfer (args.main, args.self);
405			}
406			else
407			ctx->id = null_tid;
408	root	1.30
409	root	1.1	#else
410	root	1.30	# error unsupported backend
411	root	1.1	#endif
412			}
413