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/cvs/libcoro/coro.c
Revision: 1.35
Committed: Mon Nov 3 16:05:38 2008 UTC (15 years, 7 months ago) by root
Content type: text/plain
Branch: MAIN
CVS Tags: rel-4_803
Changes since 1.34: +32 -32 lines
Log Message:
*** empty log message ***

File Contents

# 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 * 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 * 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 * This library is modelled strictly after Ralf S. Engelschalls article at
37 * http://www.gnu.org/software/pth/rse-pmt.ps. So most of the credit must
38 * go to Ralf S. Engelschall <rse@engelschall.com>.
39 */
40
41 #include "coro.h"
42
43 #if !defined(STACK_ADJUST_PTR)
44 /* IRIX is decidedly NON-unix */
45 # if __sgi
46 # define STACK_ADJUST_PTR(sp,ss) ((char *)(sp) + (ss) - 8)
47 # define STACK_ADJUST_SIZE(sp,ss) ((ss) - 8)
48 # elif (__i386__ && CORO_LINUX) || (_M_IX86 && CORO_LOSER)
49 # define STACK_ADJUST_PTR(sp,ss) ((char *)(sp) + (ss))
50 # define STACK_ADJUST_SIZE(sp,ss) (ss)
51 # elif (__amd64__ && CORO_LINUX) || ((_M_AMD64 || _M_IA64) && CORO_LOSER)
52 # define STACK_ADJUST_PTR(sp,ss) ((char *)(sp) + (ss) - 8)
53 # define STACK_ADJUST_SIZE(sp,ss) (ss)
54 # else
55 # define STACK_ADJUST_PTR(sp,ss) (sp)
56 # define STACK_ADJUST_SIZE(sp,ss) (ss)
57 # endif
58 #endif
59
60 #if CORO_UCONTEXT
61 # include <stddef.h>
62 #endif
63
64 #if CORO_SJLJ || CORO_LOSER || CORO_LINUX || CORO_IRIX || CORO_ASM
65
66 #include <stdlib.h>
67
68 #if CORO_SJLJ
69 # include <stdio.h>
70 # include <signal.h>
71 # include <unistd.h>
72 #endif
73
74 static volatile coro_func coro_init_func;
75 static volatile void *coro_init_arg;
76 static volatile coro_context *new_coro, *create_coro;
77
78 /* what we really want to detect here is wether we use a new-enough version of GAS */
79 /* instead, check for gcc 3, ELF and GNU/Linux and hope for the best */
80 #if __GNUC__ >= 3 && __ELF__ && __linux__
81 # define HAVE_CFI 1
82 #endif
83
84 static void
85 coro_init (void)
86 {
87 volatile coro_func func = coro_init_func;
88 volatile void *arg = coro_init_arg;
89
90 coro_transfer ((coro_context *)new_coro, (coro_context *)create_coro);
91
92 func ((void *)arg);
93
94 /* the new coro returned. bad. just abort() for now */
95 abort ();
96 }
97
98 # if CORO_SJLJ
99
100 static volatile int trampoline_count;
101
102 /* trampoline signal handler */
103 static void
104 trampoline (int sig)
105 {
106 if (setjmp (((coro_context *)new_coro)->env))
107 {
108 #if HAVE_CFI
109 asm (".cfi_startproc");
110 #endif
111 coro_init (); /* start it */
112 #if HAVE_CFI
113 asm (".cfi_endproc");
114 #endif
115 }
116 else
117 trampoline_count++;
118 }
119
120 # endif
121
122 #endif
123
124 #if CORO_ASM
125 asm (
126 ".text\n"
127 ".globl coro_transfer\n"
128 ".type coro_transfer, @function\n"
129 "coro_transfer:\n"
130 #if __amd64
131 # define NUM_SAVED 5
132 "\tpush %rbx\n"
133 "\tpush %r12\n"
134 "\tpush %r13\n"
135 "\tpush %r14\n"
136 "\tpush %r15\n"
137 "\tmov %rsp, (%rdi)\n"
138 "\tmov (%rsi), %rsp\n"
139 "\tpop %r15\n"
140 "\tpop %r14\n"
141 "\tpop %r13\n"
142 "\tpop %r12\n"
143 "\tpop %rbx\n"
144 #elif __i386
145 # define NUM_SAVED 4
146 "\tpush %ebx\n"
147 "\tpush %esi\n"
148 "\tpush %edi\n"
149 "\tpush %ebp\n"
150 "\tmov %esp, (%eax)\n"
151 "\tmov (%edx), %esp\n"
152 "\tpop %ebp\n"
153 "\tpop %edi\n"
154 "\tpop %esi\n"
155 "\tpop %ebx\n"
156 #else
157 # error unsupported architecture
158 #endif
159 "\tret\n"
160 );
161 #endif
162
163 #if CORO_PTHREAD
164
165 struct coro_init_args {
166 coro_func func;
167 void *arg;
168 coro_context *self, *main;
169 };
170
171 pthread_mutex_t coro_mutex = PTHREAD_MUTEX_INITIALIZER;
172
173 static void *
174 trampoline (void *args_)
175 {
176 struct coro_init_args *args = (struct coro_init_args *)args_;
177 coro_func func = args->func;
178 void *arg = args->arg;
179
180 pthread_mutex_lock (&coro_mutex);
181 pthread_cond_destroy (&args->self->c);
182 coro_transfer (args->self, args->main);
183 func (arg);
184 pthread_mutex_unlock (&coro_mutex);
185
186 return 0;
187 }
188
189 asm("");
190
191 void coro_transfer(coro_context *prev, coro_context *next)
192 {
193 pthread_cond_init (&prev->c, 0);
194 pthread_cond_signal (&next->c);
195 pthread_cond_wait (&prev->c, &coro_mutex);
196 pthread_cond_destroy (&prev->c);
197 }
198
199 #endif
200
201 /* initialize a machine state */
202 void coro_create (coro_context *ctx,
203 coro_func coro, void *arg,
204 void *sptr, long ssize)
205 {
206 #if CORO_UCONTEXT
207
208 getcontext (&(ctx->uc));
209
210 ctx->uc.uc_link = 0;
211 ctx->uc.uc_stack.ss_sp = STACK_ADJUST_PTR (sptr,ssize);
212 ctx->uc.uc_stack.ss_size = (size_t) STACK_ADJUST_SIZE (sptr,ssize);
213 ctx->uc.uc_stack.ss_flags = 0;
214
215 makecontext (&(ctx->uc), (void (*)()) coro, 1, arg);
216
217 #elif CORO_SJLJ || CORO_LOSER || CORO_LINUX || CORO_IRIX || CORO_ASM
218
219 # if CORO_SJLJ
220 stack_t ostk, nstk;
221 struct sigaction osa, nsa;
222 sigset_t nsig, osig;
223 # endif
224 coro_context nctx;
225
226 coro_init_func = coro;
227 coro_init_arg = arg;
228
229 new_coro = ctx;
230 create_coro = &nctx;
231
232 # if CORO_SJLJ
233 /* we use SIGUSR2. first block it, then fiddle with it. */
234
235 sigemptyset (&nsig);
236 sigaddset (&nsig, SIGUSR2);
237 sigprocmask (SIG_BLOCK, &nsig, &osig);
238
239 nsa.sa_handler = trampoline;
240 sigemptyset (&nsa.sa_mask);
241 nsa.sa_flags = SA_ONSTACK;
242
243 if (sigaction (SIGUSR2, &nsa, &osa))
244 {
245 perror ("sigaction");
246 abort ();
247 }
248
249 /* set the new stack */
250 nstk.ss_sp = STACK_ADJUST_PTR (sptr,ssize); /* yes, some platforms (IRIX) get this wrong. */
251 nstk.ss_size = STACK_ADJUST_SIZE (sptr,ssize);
252 nstk.ss_flags = 0;
253
254 if (sigaltstack (&nstk, &ostk) < 0)
255 {
256 perror ("sigaltstack");
257 abort ();
258 }
259
260 trampoline_count = 0;
261 kill (getpid (), SIGUSR2);
262 sigfillset (&nsig); sigdelset (&nsig, SIGUSR2);
263
264 while (!trampoline_count)
265 sigsuspend (&nsig);
266
267 sigaltstack (0, &nstk);
268 nstk.ss_flags = SS_DISABLE;
269 if (sigaltstack (&nstk, 0) < 0)
270 perror ("sigaltstack");
271
272 sigaltstack (0, &nstk);
273 if (~nstk.ss_flags & SS_DISABLE)
274 abort ();
275
276 if (~ostk.ss_flags & SS_DISABLE)
277 sigaltstack (&ostk, 0);
278
279 sigaction (SIGUSR2, &osa, 0);
280
281 sigprocmask (SIG_SETMASK, &osig, 0);
282
283 # elif CORO_LOSER
284
285 setjmp (ctx->env);
286 #if __CYGWIN__
287 ctx->env[7] = (long)((char *)sptr + ssize);
288 ctx->env[8] = (long)coro_init;
289 #elif defined(_M_IX86)
290 ((_JUMP_BUFFER *)&ctx->env)->Eip = (long)coro_init;
291 ((_JUMP_BUFFER *)&ctx->env)->Esp = (long)STACK_ADJUST_PTR (sptr, ssize);
292 #elif defined(_M_AMD64)
293 ((_JUMP_BUFFER *)&ctx->env)->Rip = (__int64)coro_init;
294 ((_JUMP_BUFFER *)&ctx->env)->Rsp = (__int64)STACK_ADJUST_PTR (sptr, ssize);
295 #elif defined(_M_IA64)
296 ((_JUMP_BUFFER *)&ctx->env)->StIIP = (__int64)coro_init;
297 ((_JUMP_BUFFER *)&ctx->env)->IntSp = (__int64)STACK_ADJUST_PTR (sptr, ssize);
298 #else
299 # error "microsoft libc or architecture not supported"
300 #endif
301
302 # elif CORO_LINUX
303
304 _setjmp (ctx->env);
305 #if __GLIBC__ >= 2 && __GLIBC_MINOR__ >= 0 && defined (JB_PC) && defined (JB_SP)
306 ctx->env[0].__jmpbuf[JB_PC] = (long)coro_init;
307 ctx->env[0].__jmpbuf[JB_SP] = (long)STACK_ADJUST_PTR (sptr, ssize);
308 #elif __GLIBC__ >= 2 && __GLIBC_MINOR__ >= 0 && defined (__mc68000__)
309 ctx->env[0].__jmpbuf[0].__aregs[0] = (long int)coro_init;
310 ctx->env[0].__jmpbuf[0].__sp = (int *)((char *)sptr + ssize);
311 #elif defined (__GNU_LIBRARY__) && defined (__i386__)
312 ctx->env[0].__jmpbuf[0].__pc = (char *)coro_init;
313 ctx->env[0].__jmpbuf[0].__sp = (void *)((char *)sptr + ssize);
314 #elif defined (__GNU_LIBRARY__) && defined (__amd64__)
315 ctx->env[0].__jmpbuf[JB_PC] = (long)coro_init;
316 ctx->env[0].__jmpbuf[JB_RSP] = (long)STACK_ADJUST_PTR (sptr, ssize);
317 #else
318 # error "linux libc or architecture not supported"
319 #endif
320
321 # elif CORO_IRIX
322
323 setjmp (ctx->env);
324 ctx->env[JB_PC] = (__uint64_t)coro_init;
325 ctx->env[JB_SP] = (__uint64_t)STACK_ADJUST_PTR (sptr, ssize);
326
327 # elif CORO_ASM
328
329 ctx->sp = (volatile void **)(ssize + (char *)sptr);
330 /* we try to allow for both functions with and without frame pointers */
331 *--ctx->sp = (void *)coro_init;
332 {
333 int i;
334 for (i = NUM_SAVED; i--; )
335 *--ctx->sp = 0;
336 }
337
338 # endif
339
340 coro_transfer ((coro_context *)create_coro, (coro_context *)new_coro);
341
342 # elif CORO_PTHREAD
343
344 pthread_t id;
345 pthread_attr_t attr;
346 coro_context nctx;
347 struct coro_init_args args;
348 static int once;
349
350 if (!once)
351 {
352 pthread_mutex_lock (&coro_mutex);
353 once = 1;
354 }
355
356 args.func = coro;
357 args.arg = arg;
358 args.self = ctx;
359 args.main = &nctx;
360
361 pthread_attr_init (&attr);
362 pthread_attr_setdetachstate (&attr, PTHREAD_CREATE_DETACHED);
363 pthread_attr_setstack (&attr, sptr, (size_t)ssize);
364 pthread_create (&id, &attr, trampoline, &args);
365
366 pthread_cond_init (&args.self->c, 0);
367 coro_transfer (args.main, args.self);
368
369 #else
370 # error unsupported backend
371 #endif
372 }
373