libcoro/coro.c

/*
 * Copyright (c) 2001-2005 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.
 * 
 *   3.  The name of the author may not be used to endorse or promote products
 *       derived from this software without specific prior written permission.
 * 
 * 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.
 *
 * 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"

#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
#  define STACK_ADJUST_PTR(sp,ss) ((char *)(sp) + (ss))
#  define STACK_ADJUST_SIZE(sp,ss) (ss)
# elif __amd64__ && CORO_LINUX
#  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_SJLJ || CORO_LOSER || CORO_LINUX || CORO_IRIX

#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;

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))
    coro_init (); /* start it */
  else
    trampoline_count++;
}

# endif

#endif

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

  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

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

  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");

  /* 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");

  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);
  ctx->env[7] = (long)((char *)sptr + ssize);
  ctx->env[8] = (long)coro_init;

# elif CORO_LINUX

  setjmp (ctx->env);
#if defined(__GLIBC__) && defined(__GLIBC_MINOR__) \
    && __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);
#elif defined(__GLIBC__) && defined(__GLIBC_MINOR__) \
    && __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);
#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);
#elif defined(__GNU_LIBRARY__) && defined(__amd64__)
  ctx->env[0].__jmpbuf[JB_PC]  = (long)coro_init;
  ctx->env[0].__jmpbuf[JB_RSP] = (long)STACK_ADJUST_PTR (sptr,ssize);
#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);

# endif

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

#else
error unsupported architecture
#endif
}

Revision:	1.19
Committed:	Wed Oct 19 19:04:24 2005 UTC (18 years, 7 months ago) by root
Content type:	text/plain
Branch:	MAIN
CVS Tags:	rel-2_0, rel-1_9, rel-1_5, rel-1_7, rel-1_6
Changes since 1.18:	+1 -1 lines
Log Message:	* empty log message *
#	Content
1	/*
2	* Copyright (c) 2001-2005 Marc Alexander Lehmann <schmorp@schmorp.de>
3	*
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	* 3. The name of the author may not be used to endorse or promote products
15	* derived from this software without specific prior written permission.
16	*
17	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
18	* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER-
19	* CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
20	* EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE-
21	* CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
22	* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
23	* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
24	* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH-
25	* ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
26	* OF THE POSSIBILITY OF SUCH DAMAGE.
27	*
28	* This library is modelled strictly after Ralf S. Engelschalls article at
29	* http://www.gnu.org/software/pth/rse-pmt.ps. So most of the credit must
30	* go to Ralf S. Engelschall <rse@engelschall.com>.
31	*/
32
33	#include "coro.h"
34
35	#if !defined(STACK_ADJUST_PTR)
36	/* IRIX is decidedly NON-unix */
37	# if __sgi
38	# define STACK_ADJUST_PTR(sp,ss) ((char *)(sp) + (ss) - 8)
39	# define STACK_ADJUST_SIZE(sp,ss) ((ss) - 8)
40	# elif __i386__ && CORO_LINUX
41	# define STACK_ADJUST_PTR(sp,ss) ((char *)(sp) + (ss))
42	# define STACK_ADJUST_SIZE(sp,ss) (ss)
43	# elif __amd64__ && CORO_LINUX
44	# define STACK_ADJUST_PTR(sp,ss) ((char *)(sp) + (ss) - 8)
45	# define STACK_ADJUST_SIZE(sp,ss) (ss)
46	# else
47	# define STACK_ADJUST_PTR(sp,ss) (sp)
48	# define STACK_ADJUST_SIZE(sp,ss) (ss)
49	# endif
50	#endif
51
52	#if CORO_SJLJ \|\| CORO_LOSER \|\| CORO_LINUX \|\| CORO_IRIX
53
54	#include <stdlib.h>
55
56	#if CORO_SJLJ
57	# include <stdio.h>
58	# include <signal.h>
59	# include <unistd.h>
60	#endif
61
62	static volatile coro_func coro_init_func;
63	static volatile void *coro_init_arg;
64	static volatile coro_context new_coro, create_coro;
65
66	static void
67	coro_init (void)
68	{
69	volatile coro_func func = coro_init_func;
70	volatile void *arg = coro_init_arg;
71
72	coro_transfer ((coro_context )new_coro, (coro_context )create_coro);
73
74	func ((void *)arg);
75
76	/* the new coro returned. bad. just abort() for now */
77	abort ();
78	}
79
80	# if CORO_SJLJ
81
82	static volatile int trampoline_count;
83
84	/* trampoline signal handler */
85	static void
86	trampoline (int sig)
87	{
88	if (setjmp (((coro_context *)new_coro)->env))
89	coro_init (); /* start it */
90	else
91	trampoline_count++;
92	}
93
94	# endif
95
96	#endif
97
98	/* initialize a machine state */
99	void coro_create(coro_context *ctx,
100	coro_func coro, void *arg,
101	void *sptr, long ssize)
102	{
103	#if CORO_UCONTEXT
104
105	getcontext (&(ctx->uc));
106
107	ctx->uc.uc_link = 0;
108	ctx->uc.uc_stack.ss_sp = STACK_ADJUST_PTR (sptr,ssize);
109	ctx->uc.uc_stack.ss_size = (size_t) STACK_ADJUST_SIZE (sptr,ssize);
110	ctx->uc.uc_stack.ss_flags = 0;
111
112	makecontext (&(ctx->uc), (void (*)()) coro, 1, arg);
113
114	#elif CORO_SJLJ \|\| CORO_LOSER \|\| CORO_LINUX \|\| CORO_IRIX
115
116	# if CORO_SJLJ
117	stack_t ostk, nstk;
118	struct sigaction osa, nsa;
119	sigset_t nsig, osig;
120	# endif
121	coro_context nctx;
122
123	coro_init_func = coro;
124	coro_init_arg = arg;
125
126	new_coro = ctx;
127	create_coro = &nctx;
128
129	# if CORO_SJLJ
130	/* we use SIGUSR2. first block it, then fiddle with it. */
131
132	sigemptyset (&nsig);
133	sigaddset (&nsig, SIGUSR2);
134	sigprocmask (SIG_BLOCK, &nsig, &osig);
135
136	nsa.sa_handler = trampoline;
137	sigemptyset (&nsa.sa_mask);
138	nsa.sa_flags = SA_ONSTACK;
139
140	if (sigaction (SIGUSR2, &nsa, &osa))
141	perror ("sigaction");
142
143	/* set the new stack */
144	nstk.ss_sp = STACK_ADJUST_PTR (sptr,ssize); /* yes, some platforms (IRIX) get this wrong. */
145	nstk.ss_size = STACK_ADJUST_SIZE (sptr,ssize);
146	nstk.ss_flags = 0;
147
148	if (sigaltstack (&nstk, &ostk) < 0)
149	perror ("sigaltstack");
150
151	trampoline_count = 0;
152	kill (getpid (), SIGUSR2);
153	sigfillset (&nsig); sigdelset (&nsig, SIGUSR2);
154
155	while (!trampoline_count)
156	sigsuspend (&nsig);
157
158	sigaltstack (0, &nstk);
159	nstk.ss_flags = SS_DISABLE;
160	if (sigaltstack (&nstk, 0) < 0)
161	perror ("sigaltstack");
162
163	sigaltstack (0, &nstk);
164	if (~nstk.ss_flags & SS_DISABLE)
165	abort ();
166
167	if (~ostk.ss_flags & SS_DISABLE)
168	sigaltstack (&ostk, 0);
169
170	sigaction (SIGUSR2, &osa, 0);
171
172	sigprocmask (SIG_SETMASK, &osig, 0);
173
174	# elif CORO_LOSER
175
176	setjmp (ctx->env);
177	ctx->env[7] = (long)((char *)sptr + ssize);
178	ctx->env[8] = (long)coro_init;
179
180	# elif CORO_LINUX
181
182	setjmp (ctx->env);
183	#if defined(__GLIBC__) && defined(__GLIBC_MINOR__) \
184	&& __GLIBC__ >= 2 && __GLIBC_MINOR__ >= 0 && defined(JB_PC) && defined(JB_SP)
185	ctx->env[0].__jmpbuf[JB_PC] = (long)coro_init;
186	ctx->env[0].__jmpbuf[JB_SP] = (long)STACK_ADJUST_PTR (sptr,ssize);
187	#elif defined(__GLIBC__) && defined(__GLIBC_MINOR__) \
188	&& __GLIBC__ >= 2 && __GLIBC_MINOR__ >= 0 && defined(__mc68000__)
189	ctx->env[0].__jmpbuf[0].__aregs[0] = (long int)coro_init;
190	ctx->env[0].__jmpbuf[0].__sp = (int )((char )sptr + ssize);
191	#elif defined(__GNU_LIBRARY__) && defined(__i386__)
192	ctx->env[0].__jmpbuf[0].__pc = (char *)coro_init;
193	ctx->env[0].__jmpbuf[0].__sp = (void )((char )sptr + ssize);
194	#elif defined(__GNU_LIBRARY__) && defined(__amd64__)
195	ctx->env[0].__jmpbuf[JB_PC] = (long)coro_init;
196	ctx->env[0].__jmpbuf[JB_RSP] = (long)STACK_ADJUST_PTR (sptr,ssize);
197	#else
198	#error "linux libc or architecture not supported"
199	#endif
200
201	# elif CORO_IRIX
202
203	setjmp (ctx->env);
204	ctx->env[JB_PC] = (__uint64_t)coro_init;
205	ctx->env[JB_SP] = (__uint64_t)STACK_ADJUST_PTR (sptr,ssize);
206
207	# endif
208
209	coro_transfer ((coro_context )create_coro, (coro_context )new_coro);
210
211	#else
212	error unsupported architecture
213	#endif
214	}
215