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Comparing libcoro/coro.c (file contents):
Revision 1.13 by root, Thu Mar 3 17:20:31 2005 UTC vs.
Revision 1.56 by root, Mon May 30 02:32:06 2011 UTC

1/* 1/*
2 * Copyright (c) 2001-2005 Marc Alexander Lehmann <schmorp@schmorp.de> 2 * Copyright (c) 2001-2011 Marc Alexander Lehmann <schmorp@schmorp.de>
3 * 3 *
4 * Redistribution and use in source and binary forms, with or without modifica- 4 * Redistribution and use in source and binary forms, with or without modifica-
5 * tion, are permitted provided that the following conditions are met: 5 * tion, are permitted provided that the following conditions are met:
6 * 6 *
7 * 1. Redistributions of source code must retain the above copyright notice, 7 * 1. Redistributions of source code must retain the above copyright notice,
8 * this list of conditions and the following disclaimer. 8 * this list of conditions and the following disclaimer.
9 * 9 *
10 * 2. Redistributions in binary form must reproduce the above copyright 10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the 11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution. 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 * 13 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 14 * 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- 15 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER-
19 * CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO 16 * CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
20 * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE- 17 * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE-
… …
23 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 20 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
24 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH- 21 * 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 22 * ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
26 * OF THE POSSIBILITY OF SUCH DAMAGE. 23 * OF THE POSSIBILITY OF SUCH DAMAGE.
27 * 24 *
25 * 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 *
28 * This library is modelled strictly after Ralf S. Engelschalls article at 36 * 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 37 * http://www.gnu.org/software/pth/rse-pmt.ps. So most of the credit must
30 * go to Ralf S. Engelschall <rse@engelschall.com>. 38 * go to Ralf S. Engelschall <rse@engelschall.com>.
31 */ 39 */
32 40
33#include "coro.h" 41#include "coro.h"
34 42
43#include <string.h>
44
45/*****************************************************************************/
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
35#if !defined(STACK_ADJUST_PTR) 54# if !defined(STACK_ADJUST_PTR)
55# if __sgi
36/* IRIX is decidedly NON-unix */ 56/* IRIX is decidedly NON-unix */
37# if __sgi
38# define STACK_ADJUST_PTR(sp,ss) ((char *)(sp) + (ss) - 8) 57# define STACK_ADJUST_PTR(sp,ss) ((char *)(sp) + (ss) - 8)
39# define STACK_ADJUST_SIZE(sp,ss) ((ss) - 8) 58# define STACK_ADJUST_SIZE(sp,ss) ((ss) - 8)
40# elif __i386__ && CORO_LINUX 59# elif (__i386__ && CORO_LINUX) || (_M_IX86 && CORO_LOSER)
41# define STACK_ADJUST_PTR(sp,ss) ((char *)(sp) + (ss)) 60# define STACK_ADJUST_PTR(sp,ss) ((char *)(sp) + (ss))
42# define STACK_ADJUST_SIZE(sp,ss) (ss) 61# define STACK_ADJUST_SIZE(sp,ss) (ss)
43# else 62# elif (__amd64__ && CORO_LINUX) || ((_M_AMD64 || _M_IA64) && CORO_LOSER)
44# define STACK_ADJUST_PTR(sp,ss) (sp) 63# define STACK_ADJUST_PTR(sp,ss) ((char *)(sp) + (ss) - 8)
45# define STACK_ADJUST_SIZE(sp,ss) (ss) 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)
46# endif 68# endif
47#endif 69# endif
48 70
49#if CORO_SJLJ || CORO_LOOSE || CORO_LINUX || CORO_IRIX 71# include <stdlib.h>
50 72
73# if CORO_SJLJ
74# include <stdio.h>
51#include <signal.h> 75# include <signal.h>
76# include <unistd.h>
77# endif
52 78
53static volatile coro_func coro_init_func; 79static coro_func coro_init_func;
54static volatile void *coro_init_arg; 80static void *coro_init_arg;
55static volatile coro_context *new_coro, *create_coro; 81static coro_context *new_coro, *create_coro;
56 82
57static void 83static void
58coro_init (void) 84coro_init (void)
59{ 85{
60 volatile coro_func func = coro_init_func; 86 volatile coro_func func = coro_init_func;
61 volatile void *arg = coro_init_arg; 87 volatile void *arg = coro_init_arg;
62 88
63 coro_transfer ((coro_context *)new_coro, (coro_context *)create_coro); 89 coro_transfer (new_coro, create_coro);
90
91#ifdef __linux && __elf
92 /* we blindly assume on any __linux with __elf we have a new enough gas with .cfi_undefined support */
93 asm (".cfi_undefined rip");
94#endif
64 95
65 func ((void *)arg); 96 func ((void *)arg);
66 97
67 /* the new coro returned. bad. just abort() for now */ 98 /* the new coro returned. bad. just abort() for now */
68 abort (); 99 abort ();
69} 100}
70 101
71# if CORO_SJLJ 102# if CORO_SJLJ
72 103
73static volatile int trampoline_count; 104static volatile int trampoline_done;
74 105
75/* trampoline signal handler */ 106/* trampoline signal handler */
76static void 107static void
77trampoline(int sig) 108trampoline (int sig)
78{ 109{
79 if (setjmp (((coro_context *)new_coro)->env)) 110 if (coro_setjmp (new_coro->env))
80 coro_init (); /* start it */ 111 coro_init (); /* start it */
81 else 112 else
82 trampoline_count++; 113 trampoline_done = 1;
83} 114}
84 115
85# endif
86
87#endif 116# endif
88 117
89/* initialize a machine state */ 118# if CORO_ASM
90void coro_create(coro_context *ctx,
91 coro_func coro, void *arg,
92 void *sptr, long ssize)
93{
94#if CORO_UCONTEXT
95 119
96 getcontext (&(ctx->uc)); 120 asm (
121 ".text\n"
122 ".globl coro_transfer\n"
123 ".type coro_transfer, @function\n"
124 "coro_transfer:\n"
125 /* 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 #if __amd64
128 #define NUM_SAVED 6
129 "\tpush %rbp\n"
130 "\tpush %rbx\n"
131 "\tpush %r12\n"
132 "\tpush %r13\n"
133 "\tpush %r14\n"
134 "\tpush %r15\n"
135 #if CORO_WIN_TIB
136 "\tpush %gs:0x0\n"
137 "\tpush %gs:0x8\n"
138 "\tpush %gs:0xc\n"
139 #endif
140 "\tmov %rsp, (%rdi)\n"
141 "\tmov (%rsi), %rsp\n"
142 #if CORO_WIN_TIB
143 "\tpop %gs:0xc\n"
144 "\tpop %gs:0x8\n"
145 "\tpop %gs:0x0\n"
146 #endif
147 "\tpop %r15\n"
148 "\tpop %r14\n"
149 "\tpop %r13\n"
150 "\tpop %r12\n"
151 "\tpop %rbx\n"
152 "\tpop %rbp\n"
153 #elif __i386
154 #define NUM_SAVED 4
155 "\tpush %ebp\n"
156 "\tpush %ebx\n"
157 "\tpush %esi\n"
158 "\tpush %edi\n"
159 #if CORO_WIN_TIB
160 "\tpush %fs:0\n"
161 "\tpush %fs:4\n"
162 "\tpush %fs:8\n"
163 #endif
164 "\tmov %esp, (%eax)\n"
165 "\tmov (%edx), %esp\n"
166 #if CORO_WIN_TIB
167 "\tpop %fs:8\n"
168 "\tpop %fs:4\n"
169 "\tpop %fs:0\n"
170 #endif
171 "\tpop %edi\n"
172 "\tpop %esi\n"
173 "\tpop %ebx\n"
174 "\tpop %ebp\n"
175 #else
176 #error unsupported architecture
177 #endif
178 "\tret\n"
179 );
97 180
98 ctx->uc.uc_link = 0; 181# endif
99 ctx->uc.uc_stack.ss_sp = STACK_ADJUST_PTR (sptr,ssize);
100 ctx->uc.uc_stack.ss_size = (size_t) STACK_ADJUST_SIZE (sptr,ssize);
101 ctx->uc.uc_stack.ss_flags = 0;
102 182
103 makecontext (&(ctx->uc), (void (*)()) coro, 1, arg); 183void
104 184coro_create (coro_context *ctx, coro_func coro, void *arg, void *sptr, long ssize)
105#elif CORO_SJLJ || CORO_LOOSE || CORO_LINUX || CORO_IRIX 185{
106 186 coro_context nctx;
107# if CORO_SJLJ 187# if CORO_SJLJ
108 stack_t ostk, nstk; 188 stack_t ostk, nstk;
109 struct sigaction osa, nsa; 189 struct sigaction osa, nsa;
110 sigset_t nsig, osig; 190 sigset_t nsig, osig;
111# endif 191# endif
112 coro_context nctx; 192
193 if (!coro)
194 return;
113 195
114 coro_init_func = coro; 196 coro_init_func = coro;
115 coro_init_arg = arg; 197 coro_init_arg = arg;
116 198
117 new_coro = ctx; 199 new_coro = ctx;
… …
127 nsa.sa_handler = trampoline; 209 nsa.sa_handler = trampoline;
128 sigemptyset (&nsa.sa_mask); 210 sigemptyset (&nsa.sa_mask);
129 nsa.sa_flags = SA_ONSTACK; 211 nsa.sa_flags = SA_ONSTACK;
130 212
131 if (sigaction (SIGUSR2, &nsa, &osa)) 213 if (sigaction (SIGUSR2, &nsa, &osa))
214 {
132 perror ("sigaction"); 215 perror ("sigaction");
216 abort ();
217 }
133 218
134 /* set the new stack */ 219 /* set the new stack */
135 nstk.ss_sp = STACK_ADJUST_PTR (sptr,ssize); /* yes, some platforms (IRIX) get this wrong. */ 220 nstk.ss_sp = STACK_ADJUST_PTR (sptr, ssize); /* yes, some platforms (IRIX) get this wrong. */
136 nstk.ss_size = STACK_ADJUST_SIZE (sptr,ssize); 221 nstk.ss_size = STACK_ADJUST_SIZE (sptr, ssize);
137 nstk.ss_flags = 0; 222 nstk.ss_flags = 0;
138 223
139 if (sigaltstack (&nstk, &ostk) < 0) 224 if (sigaltstack (&nstk, &ostk) < 0)
225 {
140 perror ("sigaltstack"); 226 perror ("sigaltstack");
227 abort ();
228 }
141 229
142 trampoline_count = 0; 230 trampoline_done = 0;
143 kill (getpid (), SIGUSR2); 231 kill (getpid (), SIGUSR2);
144 sigfillset (&nsig); sigdelset (&nsig, SIGUSR2); 232 sigfillset (&nsig); sigdelset (&nsig, SIGUSR2);
145 233
146 while (!trampoline_count) 234 while (!trampoline_done)
147 sigsuspend (&nsig); 235 sigsuspend (&nsig);
148 236
149 sigaltstack (0, &nstk); 237 sigaltstack (0, &nstk);
150 nstk.ss_flags = SS_DISABLE; 238 nstk.ss_flags = SS_DISABLE;
151 if (sigaltstack (&nstk, 0) < 0) 239 if (sigaltstack (&nstk, 0) < 0)
… …
156 abort (); 244 abort ();
157 245
158 if (~ostk.ss_flags & SS_DISABLE) 246 if (~ostk.ss_flags & SS_DISABLE)
159 sigaltstack (&ostk, 0); 247 sigaltstack (&ostk, 0);
160 248
161 sigaction (SIGUSR1, &osa, 0); 249 sigaction (SIGUSR2, &osa, 0);
162
163 sigprocmask (SIG_SETMASK, &osig, 0); 250 sigprocmask (SIG_SETMASK, &osig, 0);
164 251
165# elif CORO_LOOSE 252# elif CORO_LOSER
166 253
167 setjmp (ctx->env); 254 coro_setjmp (ctx->env);
168 ctx->env[7] = (long)((char *)sptr + ssize); 255 #if __CYGWIN__ && __i386
169 ctx->env[8] = (long)coro_init; 256 ctx->env[8] = (long) coro_init;
257 ctx->env[7] = (long) ((char *)sptr + ssize) - sizeof (long);
258 #elif __CYGWIN__ && __x86_64
259 ctx->env[7] = (long) coro_init;
260 ctx->env[6] = (long) ((char *)sptr + ssize) - sizeof (long);
261 #elif defined(__MINGW32__)
262 ctx->env[5] = (long) coro_init;
263 ctx->env[4] = (long) ((char *)sptr + ssize) - sizeof (long);
264 #elif defined(_M_IX86)
265 ((_JUMP_BUFFER *)&ctx->env)->Eip = (long) coro_init;
266 ((_JUMP_BUFFER *)&ctx->env)->Esp = (long) STACK_ADJUST_PTR (sptr, ssize) - sizeof (long);
267 #elif defined(_M_AMD64)
268 ((_JUMP_BUFFER *)&ctx->env)->Rip = (__int64) coro_init;
269 ((_JUMP_BUFFER *)&ctx->env)->Rsp = (__int64) STACK_ADJUST_PTR (sptr, ssize) - sizeof (__int64);
270 #elif defined(_M_IA64)
271 ((_JUMP_BUFFER *)&ctx->env)->StIIP = (__int64) coro_init;
272 ((_JUMP_BUFFER *)&ctx->env)->IntSp = (__int64) STACK_ADJUST_PTR (sptr, ssize) - sizeof (__int64);
273 #else
274 #error "microsoft libc or architecture not supported"
275 #endif
170 276
171# elif CORO_LINUX 277# elif CORO_LINUX
172 278
173 setjmp (ctx->env); 279 coro_setjmp (ctx->env);
174#if defined(__GLIBC__) && defined(__GLIBC_MINOR__) \
175 && __GLIBC__ >= 2 && __GLIBC_MINOR__ >= 0 && defined(JB_PC) && defined(JB_SP) 280 #if __GLIBC__ >= 2 && __GLIBC_MINOR__ >= 0 && defined (JB_PC) && defined (JB_SP)
176 ctx->env[0].__jmpbuf[JB_PC] = (long)coro_init; 281 ctx->env[0].__jmpbuf[JB_PC] = (long) coro_init;
177 ctx->env[0].__jmpbuf[JB_SP] = (long)STACK_ADJUST_PTR (sptr,ssize); 282 ctx->env[0].__jmpbuf[JB_SP] = (long) STACK_ADJUST_PTR (sptr, ssize) - sizeof (long);
178#elif defined(__GLIBC__) && defined(__GLIBC_MINOR__) \
179 && __GLIBC__ >= 2 && __GLIBC_MINOR__ >= 0 && defined(__mc68000__) 283 #elif __GLIBC__ >= 2 && __GLIBC_MINOR__ >= 0 && defined (__mc68000__)
180 ctx->env[0].__jmpbuf[0].__aregs[0] = (long int)coro_init; 284 ctx->env[0].__jmpbuf[0].__aregs[0] = (long int)coro_init;
181 ctx->env[0].__jmpbuf[0].__sp = (int *)((char *)sptr + ssize); 285 ctx->env[0].__jmpbuf[0].__sp = (int *) ((char *)sptr + ssize) - sizeof (long);
182#elif defined(__GNU_LIBRARY__) && defined(__i386__) 286 #elif defined (__GNU_LIBRARY__) && defined (__i386__)
183 ctx->env[0].__jmpbuf[0].__pc = (char *)coro_init; 287 ctx->env[0].__jmpbuf[0].__pc = (char *) coro_init;
184 ctx->env[0].__jmpbuf[0].__sp = (void *)((char *)sptr + ssize); 288 ctx->env[0].__jmpbuf[0].__sp = (void *) ((char *)sptr + ssize) - sizeof (long);
185#elif defined(__GNU_LIBRARY__) && defined(__amd64__) 289 #elif defined (__GNU_LIBRARY__) && defined (__amd64__)
186 ctx->env[0].__jmpbuf[JB_PC] = (long)coro_init; 290 ctx->env[0].__jmpbuf[JB_PC] = (long) coro_init;
187 ctx->env[0].__jmpbuf[JB_RSP] = (long)((char *)sptr + ssize); 291 ctx->env[0].__jmpbuf[0].__sp = (void *) ((char *)sptr + ssize) - sizeof (long);
292 #else
293 #error "linux libc or architecture not supported"
294 #endif
295
296# elif CORO_IRIX
297
298 coro_setjmp (ctx->env, 0);
299 ctx->env[JB_PC] = (__uint64_t)coro_init;
300 ctx->env[JB_SP] = (__uint64_t)STACK_ADJUST_PTR (sptr, ssize) - sizeof (long);
301
302# elif CORO_ASM
303
304 ctx->sp = (void **)(ssize + (char *)sptr);
305 *--ctx->sp = (void *)abort; /* needed for alignment only */
306 *--ctx->sp = (void *)coro_init;
307
308 #if CORO_WIN_TIB
309 *--ctx->sp = 0; /* ExceptionList */
310 *--ctx->sp = (char *)sptr + ssize; /* StackBase */
311 *--ctx->sp = sptr; /* StackLimit */
312 #endif
313
314 ctx->sp -= NUM_SAVED;
315 memset (ctx->sp, 0, sizeof (*ctx->sp) * NUM_SAVED);
316
317# elif CORO_UCONTEXT
318
319 getcontext (&(ctx->uc));
320
321 ctx->uc.uc_link = 0;
322 ctx->uc.uc_stack.ss_sp = sptr;
323 ctx->uc.uc_stack.ss_size = (size_t)ssize;
324 ctx->uc.uc_stack.ss_flags = 0;
325
326 makecontext (&(ctx->uc), (void (*)())coro_init, 0);
327
328# endif
329
330 coro_transfer (create_coro, new_coro);
331}
332
333/*****************************************************************************/
334/* pthread backend */
335/*****************************************************************************/
336#elif CORO_PTHREAD
337
338/* this mutex will be locked by the running coroutine */
339pthread_mutex_t coro_mutex = PTHREAD_MUTEX_INITIALIZER;
340
341struct coro_init_args
342{
343 coro_func func;
344 void *arg;
345 coro_context *self, *main;
346};
347
348static pthread_t null_tid;
349
350/* I'd so love to cast pthread_mutex_unlock to void (*)(void *)... */
351static void
352mutex_unlock_wrapper (void *arg)
353{
354 pthread_mutex_unlock ((pthread_mutex_t *)arg);
355}
356
357static void *
358coro_init (void *args_)
359{
360 struct coro_init_args *args = (struct coro_init_args *)args_;
361 coro_func func = args->func;
362 void *arg = args->arg;
363
364 pthread_mutex_lock (&coro_mutex);
365
366 /* we try to be good citizens and use deferred cancellation and cleanup handlers */
367 pthread_cleanup_push (mutex_unlock_wrapper, &coro_mutex);
368 coro_transfer (args->self, args->main);
369 func (arg);
370 pthread_cleanup_pop (1);
371
372 return 0;
373}
374
375void
376coro_transfer (coro_context *prev, coro_context *next)
377{
378 pthread_cond_signal (&next->cv);
379 pthread_cond_wait (&prev->cv, &coro_mutex);
380#if __FreeBSD__ /* freebsd is of course broken and needs manual testcancel calls... yay... */
381 pthread_testcancel ();
382#endif
383}
384
385void
386coro_create (coro_context *ctx, coro_func coro, void *arg, void *sptr, long ssize)
387{
388 static coro_context nctx;
389 static int once;
390
391 if (!once)
392 {
393 once = 1;
394
395 pthread_mutex_lock (&coro_mutex);
396 pthread_cond_init (&nctx.cv, 0);
397 null_tid = pthread_self ();
398 }
399
400 pthread_cond_init (&ctx->cv, 0);
401
402 if (coro)
403 {
404 pthread_attr_t attr;
405 struct coro_init_args args;
406
407 args.func = coro;
408 args.arg = arg;
409 args.self = ctx;
410 args.main = &nctx;
411
412 pthread_attr_init (&attr);
413#if __UCLIBC__
414 /* exists, but is borked */
415 /*pthread_attr_setstacksize (&attr, (size_t)ssize);*/
188#else 416#else
189#error "linux libc or architecture not supported" 417 pthread_attr_setstack (&attr, sptr, (size_t)ssize);
190#endif 418#endif
419 pthread_attr_setscope (&attr, PTHREAD_SCOPE_PROCESS);
420 pthread_create (&ctx->id, &attr, coro_init, &args);
191 421
192# elif CORO_IRIX 422 coro_transfer (args.main, args.self);
423 }
424 else
425 ctx->id = null_tid;
426}
193 427
194 setjmp (ctx->env); 428void
195 ctx->env[JB_PC] = (__uint64_t)coro_init; 429coro_destroy (coro_context *ctx)
196 ctx->env[JB_SP] = (__uint64_t)STACK_ADJUST_PTR (sptr,ssize); 430{
431 if (!pthread_equal (ctx->id, null_tid))
432 {
433 pthread_cancel (ctx->id);
434 pthread_mutex_unlock (&coro_mutex);
435 pthread_join (ctx->id, 0);
436 pthread_mutex_lock (&coro_mutex);
437 }
197 438
198# endif 439 pthread_cond_destroy (&ctx->cv);
199 440}
200 coro_transfer ((coro_context *)create_coro, (coro_context *)new_coro);
201 441
202#else 442#else
203error unsupported architecture 443# error unsupported backend
204#endif 444#endif
205}
206 445

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