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.
 * 
 *   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_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
void __attribute__((__noinline__, __fastcall__))
coro_transfer (struct coro_context *prev, struct coro_context *next)
{
  asm volatile (
#if __amd64
# define NUM_CLOBBERED 5
     "push %%rbx\n\t"
     "push %%r12\n\t"
     "push %%r13\n\t"
     "push %%r14\n\t"
     "push %%r15\n\t"
     "mov  %%rsp, %0\n\t"
     "mov  %1, %%rsp\n\t"
     "pop  %%r15\n\t"
     "pop  %%r14\n\t"
     "pop  %%r13\n\t"
     "pop  %%r12\n\t"
     "pop  %%rbx\n\t"
#elif __i386
# define NUM_CLOBBERED 4
     "push %%ebx\n\t"
     "push %%esi\n\t"
     "push %%edi\n\t"
     "push %%ebp\n\t"
     "mov  %%esp, %0\n\t"
     "mov  %1, %%esp\n\t"
     "pop  %%ebp\n\t"
     "pop  %%edi\n\t"
     "pop  %%esi\n\t"
     "pop  %%ebx\n\t"
#else
# error unsupported architecture
#endif
     : "=m" (prev->sp)
     : "m" (next->sp)
  );
}
#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 || CORO_ASM

# 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");
      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);
  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);
#elif defined(_M_AMD64)
  ((_JUMP_BUFFER *)&ctx->env)->Rip   = (__int64)coro_init;
  ((_JUMP_BUFFER *)&ctx->env)->Rsp   = (__int64)STACK_ADJUST_PTR (sptr,ssize);
#elif defined(_M_IA64)
  ((_JUMP_BUFFER *)&ctx->env)->StIIP = (__int64)coro_init;
  ((_JUMP_BUFFER *)&ctx->env)->IntSp = (__int64)STACK_ADJUST_PTR (sptr,ssize);
#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);
#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);
#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);

# elif CORO_ASM

  ctx->sp = (volatile void **)(ssize + (char *)sptr);
  *--ctx->sp = (void *)coro_init;
  *--ctx->sp = (void *)coro_init; // this is needed when the prologue saves ebp
  ctx->sp -= NUM_CLOBBERED;

# endif

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

#else
# error unsupported architecture
#endif
}

Revision:	1.28
Committed:	Sun Jan 20 17:30:24 2008 UTC (16 years, 4 months ago) by root
Content type:	text/plain
Branch:	MAIN
CVS Tags:	rel-4_4
Changes since 1.27:	+3 -3 lines
Log Message:	* empty log message *
#	Content
1	/*
2	* Copyright (c) 2001-2008 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_UCONTEXT
53	# include <stddef.h>
54	#endif
55
56	#if CORO_SJLJ \|\| CORO_LOSER \|\| CORO_LINUX \|\| CORO_IRIX \|\| CORO_ASM
57
58	#include <stdlib.h>
59
60	#if CORO_SJLJ
61	# include <stdio.h>
62	# include <signal.h>
63	# include <unistd.h>
64	#endif
65
66	static volatile coro_func coro_init_func;
67	static volatile void *coro_init_arg;
68	static volatile coro_context new_coro, create_coro;
69
70	/* what we really want to detect here is wether we use a new-enough version of GAS */
71	/* instead, check for gcc 3, ELF and GNU/Linux and hope for the best */
72	#if __GNUC__ >= 3 && __ELF__ && __linux__
73	# define HAVE_CFI 1
74	#endif
75
76	static void
77	coro_init (void)
78	{
79	volatile coro_func func = coro_init_func;
80	volatile void *arg = coro_init_arg;
81
82	coro_transfer ((coro_context )new_coro, (coro_context )create_coro);
83
84	func ((void *)arg);
85
86	/* the new coro returned. bad. just abort() for now */
87	abort ();
88	}
89
90	# if CORO_SJLJ
91
92	static volatile int trampoline_count;
93
94	/* trampoline signal handler */
95	static void
96	trampoline (int sig)
97	{
98	if (setjmp (((coro_context *)new_coro)->env))
99	{
100	#if HAVE_CFI
101	asm (".cfi_startproc");
102	#endif
103	coro_init (); /* start it */
104	#if HAVE_CFI
105	asm (".cfi_endproc");
106	#endif
107	}
108	else
109	trampoline_count++;
110	}
111
112	# endif
113
114	#endif
115
116	#if CORO_ASM
117	void __attribute__((__noinline__, __fastcall__))
118	coro_transfer (struct coro_context prev, struct coro_context next)
119	{
120	asm volatile (
121	#if __amd64
122	# define NUM_CLOBBERED 5
123	"push %%rbx\n\t"
124	"push %%r12\n\t"
125	"push %%r13\n\t"
126	"push %%r14\n\t"
127	"push %%r15\n\t"
128	"mov %%rsp, %0\n\t"
129	"mov %1, %%rsp\n\t"
130	"pop %%r15\n\t"
131	"pop %%r14\n\t"
132	"pop %%r13\n\t"
133	"pop %%r12\n\t"
134	"pop %%rbx\n\t"
135	#elif __i386
136	# define NUM_CLOBBERED 4
137	"push %%ebx\n\t"
138	"push %%esi\n\t"
139	"push %%edi\n\t"
140	"push %%ebp\n\t"
141	"mov %%esp, %0\n\t"
142	"mov %1, %%esp\n\t"
143	"pop %%ebp\n\t"
144	"pop %%edi\n\t"
145	"pop %%esi\n\t"
146	"pop %%ebx\n\t"
147	#else
148	# error unsupported architecture
149	#endif
150	: "=m" (prev->sp)
151	: "m" (next->sp)
152	);
153	}
154	#endif
155
156	/* initialize a machine state */
157	void coro_create (coro_context *ctx,
158	coro_func coro, void *arg,
159	void *sptr, long ssize)
160	{
161	#if CORO_UCONTEXT
162
163	getcontext (&(ctx->uc));
164
165	ctx->uc.uc_link = 0;
166	ctx->uc.uc_stack.ss_sp = STACK_ADJUST_PTR (sptr,ssize);
167	ctx->uc.uc_stack.ss_size = (size_t) STACK_ADJUST_SIZE (sptr,ssize);
168	ctx->uc.uc_stack.ss_flags = 0;
169
170	makecontext (&(ctx->uc), (void (*)()) coro, 1, arg);
171
172	#elif CORO_SJLJ \|\| CORO_LOSER \|\| CORO_LINUX \|\| CORO_IRIX \|\| CORO_ASM
173
174	# if CORO_SJLJ
175	stack_t ostk, nstk;
176	struct sigaction osa, nsa;
177	sigset_t nsig, osig;
178	# endif
179	coro_context nctx;
180
181	coro_init_func = coro;
182	coro_init_arg = arg;
183
184	new_coro = ctx;
185	create_coro = &nctx;
186
187	# if CORO_SJLJ
188	/* we use SIGUSR2. first block it, then fiddle with it. */
189
190	sigemptyset (&nsig);
191	sigaddset (&nsig, SIGUSR2);
192	sigprocmask (SIG_BLOCK, &nsig, &osig);
193
194	nsa.sa_handler = trampoline;
195	sigemptyset (&nsa.sa_mask);
196	nsa.sa_flags = SA_ONSTACK;
197
198	if (sigaction (SIGUSR2, &nsa, &osa))
199	{
200	perror ("sigaction");
201	abort ();
202	}
203
204	/* set the new stack */
205	nstk.ss_sp = STACK_ADJUST_PTR (sptr,ssize); /* yes, some platforms (IRIX) get this wrong. */
206	nstk.ss_size = STACK_ADJUST_SIZE (sptr,ssize);
207	nstk.ss_flags = 0;
208
209	if (sigaltstack (&nstk, &ostk) < 0)
210	{
211	perror ("sigaltstack");
212	abort ();
213	}
214
215	trampoline_count = 0;
216	kill (getpid (), SIGUSR2);
217	sigfillset (&nsig); sigdelset (&nsig, SIGUSR2);
218
219	while (!trampoline_count)
220	sigsuspend (&nsig);
221
222	sigaltstack (0, &nstk);
223	nstk.ss_flags = SS_DISABLE;
224	if (sigaltstack (&nstk, 0) < 0)
225	perror ("sigaltstack");
226
227	sigaltstack (0, &nstk);
228	if (~nstk.ss_flags & SS_DISABLE)
229	abort ();
230
231	if (~ostk.ss_flags & SS_DISABLE)
232	sigaltstack (&ostk, 0);
233
234	sigaction (SIGUSR2, &osa, 0);
235
236	sigprocmask (SIG_SETMASK, &osig, 0);
237
238	# elif CORO_LOSER
239
240	setjmp (ctx->env);
241	#if __CYGWIN__
242	ctx->env[7] = (long)((char *)sptr + ssize);
243	ctx->env[8] = (long)coro_init;
244	#elif defined(_M_IX86)
245	((_JUMP_BUFFER *)&ctx->env)->Eip = (long)coro_init;
246	((_JUMP_BUFFER *)&ctx->env)->Esp = (long)STACK_ADJUST_PTR (sptr,ssize);
247	#elif defined(_M_AMD64)
248	((_JUMP_BUFFER *)&ctx->env)->Rip = (__int64)coro_init;
249	((_JUMP_BUFFER *)&ctx->env)->Rsp = (__int64)STACK_ADJUST_PTR (sptr,ssize);
250	#elif defined(_M_IA64)
251	((_JUMP_BUFFER *)&ctx->env)->StIIP = (__int64)coro_init;
252	((_JUMP_BUFFER *)&ctx->env)->IntSp = (__int64)STACK_ADJUST_PTR (sptr,ssize);
253	#else
254	#error "microsoft libc or architecture not supported"
255	#endif
256
257	# elif CORO_LINUX
258
259	_setjmp (ctx->env);
260	#if __GLIBC__ >= 2 && __GLIBC_MINOR__ >= 0 && defined (JB_PC) && defined (JB_SP)
261	ctx->env[0].__jmpbuf[JB_PC] = (long)coro_init;
262	ctx->env[0].__jmpbuf[JB_SP] = (long)STACK_ADJUST_PTR (sptr, ssize);
263	#elif __GLIBC__ >= 2 && __GLIBC_MINOR__ >= 0 && defined (__mc68000__)
264	ctx->env[0].__jmpbuf[0].__aregs[0] = (long int)coro_init;
265	ctx->env[0].__jmpbuf[0].__sp = (int )((char )sptr + ssize);
266	#elif defined (__GNU_LIBRARY__) && defined (__i386__)
267	ctx->env[0].__jmpbuf[0].__pc = (char *)coro_init;
268	ctx->env[0].__jmpbuf[0].__sp = (void )((char )sptr + ssize);
269	#elif defined (__GNU_LIBRARY__) && defined (__amd64__)
270	ctx->env[0].__jmpbuf[JB_PC] = (long)coro_init;
271	ctx->env[0].__jmpbuf[JB_RSP] = (long)STACK_ADJUST_PTR (sptr, ssize);
272	#else
273	# error "linux libc or architecture not supported"
274	#endif
275
276	# elif CORO_IRIX
277
278	setjmp (ctx->env);
279	ctx->env[JB_PC] = (__uint64_t)coro_init;
280	ctx->env[JB_SP] = (__uint64_t)STACK_ADJUST_PTR (sptr, ssize);
281
282	# elif CORO_ASM
283
284	ctx->sp = (volatile void *)(ssize + (char )sptr);
285	--ctx->sp = (void )coro_init;
286	--ctx->sp = (void )coro_init; // this is needed when the prologue saves ebp
287	ctx->sp -= NUM_CLOBBERED;
288
289	# endif
290
291	coro_transfer ((coro_context )create_coro, (coro_context )new_coro);
292
293	#else
294	# error unsupported architecture
295	#endif
296	}
297