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d90ca38d | 1 | /* Copyright (C) 1995, 1996, 1997, 1998 Free Software Foundation, Inc. |
7bfd3b9e JB |
2 | * |
3 | * This program is free software; you can redistribute it and/or modify | |
4 | * it under the terms of the GNU General Public License as published by | |
5 | * the Free Software Foundation; either version 2, or (at your option) | |
6 | * any later version. | |
7 | * | |
8 | * This program is distributed in the hope that it will be useful, | |
9 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
10 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
11 | * GNU General Public License for more details. | |
12 | * | |
13 | * You should have received a copy of the GNU General Public License | |
14 | * along with this software; see the file COPYING. If not, write to | |
82892bed JB |
15 | * the Free Software Foundation, Inc., 59 Temple Place, Suite 330, |
16 | * Boston, MA 02111-1307 USA | |
7bfd3b9e JB |
17 | * |
18 | * As a special exception, the Free Software Foundation gives permission | |
19 | * for additional uses of the text contained in its release of GUILE. | |
20 | * | |
21 | * The exception is that, if you link the GUILE library with other files | |
22 | * to produce an executable, this does not by itself cause the | |
23 | * resulting executable to be covered by the GNU General Public License. | |
24 | * Your use of that executable is in no way restricted on account of | |
25 | * linking the GUILE library code into it. | |
26 | * | |
27 | * This exception does not however invalidate any other reasons why | |
28 | * the executable file might be covered by the GNU General Public License. | |
29 | * | |
30 | * This exception applies only to the code released by the | |
31 | * Free Software Foundation under the name GUILE. If you copy | |
32 | * code from other Free Software Foundation releases into a copy of | |
33 | * GUILE, as the General Public License permits, the exception does | |
34 | * not apply to the code that you add in this way. To avoid misleading | |
35 | * anyone as to the status of such modified files, you must delete | |
36 | * this exception notice from them. | |
37 | * | |
38 | * If you write modifications of your own for GUILE, it is your choice | |
39 | * whether to permit this exception to apply to your modifications. | |
82892bed | 40 | * If you do not wish that, delete this exception notice. */ |
0c95b57d GB |
41 | |
42 | /* Software engineering face-lift by Greg J. Badros, 11-Dec-1999, | |
43 | gjb@cs.washington.edu, http://www.cs.washington.edu/homes/gjb */ | |
44 | ||
7bfd3b9e JB |
45 | \f |
46 | ||
0c95b57d | 47 | #include "scm_validate.h" |
7bfd3b9e JB |
48 | #include "coop-threads.h" |
49 | ||
50 | /* A counter of the current number of threads */ | |
51 | size_t scm_thread_count = 0; | |
52 | ||
53 | /* This is included rather than compiled separately in order | |
54 | to simplify the configuration mechanism. */ | |
55 | #include "coop.c" | |
56 | ||
57 | /* A count-down counter used to determine when to switch | |
58 | contexts */ | |
59 | size_t scm_switch_counter = SCM_THREAD_SWITCH_COUNT; | |
60 | ||
61 | coop_m scm_critical_section_mutex; | |
62 | ||
7bfd3b9e JB |
63 | void |
64 | scm_threads_init (SCM_STACKITEM *i) | |
7bfd3b9e JB |
65 | { |
66 | coop_init(); | |
67 | ||
68 | scm_thread_count = 1; | |
69 | ||
70 | coop_global_main.sto = i; | |
71 | coop_global_main.base = i; | |
72 | coop_global_curr = &coop_global_main; | |
73 | coop_all_qput (&coop_global_allq, coop_global_curr); | |
74 | ||
75 | coop_mutex_init (&scm_critical_section_mutex); | |
76 | ||
77 | coop_global_main.data = 0; /* Initialized in init.c */ | |
78 | } | |
79 | ||
7bfd3b9e | 80 | void |
0c95b57d | 81 | scm_threads_mark_stacks (void) |
7bfd3b9e JB |
82 | { |
83 | coop_t *thread; | |
84 | ||
85 | for (thread = coop_global_allq.t.all_next; | |
86 | thread != NULL; thread = thread->all_next) | |
87 | { | |
88 | if (thread == coop_global_curr) | |
89 | { | |
90 | /* Active thread */ | |
91 | /* stack_len is long rather than sizet in order to guarantee | |
92 | that &stack_len is long aligned */ | |
93 | #ifdef STACK_GROWS_UP | |
94 | long stack_len = ((SCM_STACKITEM *) (&thread) - | |
95 | (SCM_STACKITEM *) thread->base); | |
96 | ||
97 | /* Protect from the C stack. This must be the first marking | |
98 | * done because it provides information about what objects | |
99 | * are "in-use" by the C code. "in-use" objects are those | |
100 | * for which the values from SCM_LENGTH and SCM_CHARS must remain | |
101 | * usable. This requirement is stricter than a liveness | |
102 | * requirement -- in particular, it constrains the implementation | |
103 | * of scm_resizuve. | |
104 | */ | |
105 | SCM_FLUSH_REGISTER_WINDOWS; | |
106 | /* This assumes that all registers are saved into the jmp_buf */ | |
107 | setjmp (scm_save_regs_gc_mark); | |
108 | scm_mark_locations ((SCM_STACKITEM *) scm_save_regs_gc_mark, | |
109 | ((scm_sizet) sizeof scm_save_regs_gc_mark | |
110 | / sizeof (SCM_STACKITEM))); | |
111 | ||
112 | scm_mark_locations (((size_t) thread->base, | |
113 | (sizet) stack_len)); | |
114 | #else | |
115 | long stack_len = ((SCM_STACKITEM *) thread->base - | |
116 | (SCM_STACKITEM *) (&thread)); | |
117 | ||
118 | /* Protect from the C stack. This must be the first marking | |
119 | * done because it provides information about what objects | |
120 | * are "in-use" by the C code. "in-use" objects are those | |
121 | * for which the values from SCM_LENGTH and SCM_CHARS must remain | |
122 | * usable. This requirement is stricter than a liveness | |
123 | * requirement -- in particular, it constrains the implementation | |
124 | * of scm_resizuve. | |
125 | */ | |
126 | SCM_FLUSH_REGISTER_WINDOWS; | |
127 | /* This assumes that all registers are saved into the jmp_buf */ | |
128 | setjmp (scm_save_regs_gc_mark); | |
129 | scm_mark_locations ((SCM_STACKITEM *) scm_save_regs_gc_mark, | |
130 | ((scm_sizet) sizeof scm_save_regs_gc_mark | |
131 | / sizeof (SCM_STACKITEM))); | |
132 | ||
133 | scm_mark_locations ((SCM_STACKITEM *) &thread, | |
134 | stack_len); | |
135 | #endif | |
136 | } | |
137 | else | |
138 | { | |
139 | /* Suspended thread */ | |
140 | #ifdef STACK_GROWS_UP | |
141 | long stack_len = ((SCM_STACKITEM *) (thread->sp) - | |
142 | (SCM_STACKITEM *) thread->base); | |
143 | ||
144 | scm_mark_locations ((size_t)thread->base, | |
145 | (sizet) stack_len); | |
146 | #else | |
147 | long stack_len = ((SCM_STACKITEM *) thread->base - | |
148 | (SCM_STACKITEM *) (thread->sp)); | |
149 | ||
150 | /* Registers are already on the stack. No need to mark. */ | |
151 | ||
152 | scm_mark_locations ((SCM_STACKITEM *) (size_t)thread->sp, | |
153 | stack_len); | |
154 | #endif | |
155 | } | |
156 | ||
157 | /* Mark this thread's root */ | |
158 | scm_gc_mark (((scm_root_state *) thread->data) -> handle); | |
159 | } | |
160 | } | |
161 | ||
df366c26 MD |
162 | /* NOTE: There are TWO mechanisms for starting a thread: The first one |
163 | is used when spawning a thread from Scheme, while the second one is | |
164 | used from C. | |
165 | ||
166 | It might be argued that the first should be implemented in terms of | |
167 | the second. The reason it isn't is that that would require an | |
168 | extra unnecessary malloc (the thread_args structure). By providing | |
169 | one pair of extra functions (c_launch_thread, scm_spawn_thread) the | |
170 | Scheme threads are started more efficiently. */ | |
171 | ||
172 | /* This is the first thread spawning mechanism: threads from Scheme */ | |
173 | ||
0a1a92ab MD |
174 | typedef struct scheme_launch_data { |
175 | SCM rootcont; | |
176 | SCM body; | |
177 | SCM handler; | |
178 | } scheme_launch_data; | |
179 | ||
180 | extern SCM scm_apply (SCM, SCM, SCM); | |
181 | ||
182 | static SCM | |
39752bec | 183 | scheme_body_bootstrip (scheme_launch_data* data) |
0a1a92ab MD |
184 | { |
185 | /* First save the new root continuation */ | |
186 | data->rootcont = scm_root->rootcont; | |
187 | return scm_apply (data->body, SCM_EOL, SCM_EOL); | |
188 | } | |
189 | ||
190 | static SCM | |
191 | scheme_handler_bootstrip (scheme_launch_data* data, SCM tag, SCM throw_args) | |
192 | { | |
193 | scm_root->rootcont = data->rootcont; | |
194 | return scm_apply (data->handler, scm_cons (tag, throw_args), SCM_EOL); | |
195 | } | |
196 | ||
df366c26 MD |
197 | static void |
198 | scheme_launch_thread (void *p) | |
7bfd3b9e JB |
199 | { |
200 | /* The thread object will be GC protected by being a member of the | |
201 | list given as argument to launch_thread. It will be marked | |
202 | during the conservative sweep of the stack. */ | |
0a1a92ab MD |
203 | register SCM argl = (SCM) p; |
204 | SCM thread = SCM_CAR (argl); | |
205 | scheme_launch_data data; | |
206 | data.rootcont = SCM_BOOL_F; | |
207 | data.body = SCM_CADR (argl); | |
208 | data.handler = SCM_CADDR (argl); | |
209 | scm_internal_cwdr ((scm_catch_body_t) scheme_body_bootstrip, | |
210 | &data, | |
211 | (scm_catch_handler_t) scheme_handler_bootstrip, | |
212 | &data, | |
213 | &thread); | |
7bfd3b9e | 214 | scm_thread_count--; |
0a1a92ab | 215 | SCM_DEFER_INTS; |
7bfd3b9e JB |
216 | } |
217 | ||
7bfd3b9e JB |
218 | SCM |
219 | scm_call_with_new_thread (SCM argl) | |
7bfd3b9e JB |
220 | { |
221 | SCM thread; | |
222 | ||
223 | /* Check arguments. */ | |
224 | { | |
225 | register SCM args = argl; | |
226 | SCM thunk, handler; | |
0824b524 MD |
227 | SCM_ASSERT (SCM_NIMP (args), |
228 | scm_makfrom0str (s_call_with_new_thread), | |
229 | SCM_WNA, NULL); | |
7bfd3b9e JB |
230 | thunk = SCM_CAR (args); |
231 | SCM_ASSERT (SCM_NFALSEP (scm_thunk_p (thunk)), | |
232 | thunk, | |
233 | SCM_ARG1, | |
234 | s_call_with_new_thread); | |
235 | args = SCM_CDR (args); | |
0824b524 MD |
236 | SCM_ASSERT (SCM_NIMP (args), |
237 | scm_makfrom0str (s_call_with_new_thread), | |
238 | SCM_WNA, NULL); | |
7bfd3b9e JB |
239 | handler = SCM_CAR (args); |
240 | SCM_ASSERT (SCM_NFALSEP (scm_procedure_p (handler)), | |
241 | handler, | |
242 | SCM_ARG2, | |
243 | s_call_with_new_thread); | |
0824b524 MD |
244 | SCM_ASSERT (SCM_NULLP (SCM_CDR (args)), |
245 | scm_makfrom0str (s_call_with_new_thread), | |
246 | SCM_WNA, NULL); | |
7bfd3b9e JB |
247 | } |
248 | ||
249 | /* Make new thread. */ | |
250 | { | |
251 | coop_t *t; | |
252 | SCM root, old_winds; | |
253 | ||
254 | /* Unwind wind chain. */ | |
255 | old_winds = scm_dynwinds; | |
256 | scm_dowinds (SCM_EOL, scm_ilength (scm_root->dynwinds)); | |
257 | ||
258 | /* Allocate thread locals. */ | |
259 | root = scm_make_root (scm_root->handle); | |
260 | /* Make thread. */ | |
261 | SCM_NEWCELL (thread); | |
262 | SCM_DEFER_INTS; | |
263 | SCM_SETCAR (thread, scm_tc16_thread); | |
264 | argl = scm_cons (thread, argl); | |
0a1a92ab MD |
265 | /* Note that we couldn't pass a pointer to argl as data since the |
266 | argl variable may not exist in memory when the thread starts. */ | |
df366c26 | 267 | t = coop_create (scheme_launch_thread, (void *) argl); |
7bfd3b9e JB |
268 | t->data = SCM_ROOT_STATE (root); |
269 | SCM_SETCDR (thread, t); | |
270 | scm_thread_count++; | |
271 | /* Note that the following statement also could cause coop_yield.*/ | |
272 | SCM_ALLOW_INTS; | |
273 | ||
274 | /* We're now ready for the thread to begin. */ | |
275 | coop_yield(); | |
276 | ||
277 | /* Return to old dynamic context. */ | |
278 | scm_dowinds (old_winds, - scm_ilength (old_winds)); | |
279 | } | |
280 | ||
281 | return thread; | |
282 | } | |
283 | ||
df366c26 MD |
284 | /* This is the second thread spawning mechanism: threads from C */ |
285 | ||
0a1a92ab MD |
286 | typedef struct c_launch_data { |
287 | union { | |
288 | SCM thread; | |
289 | SCM rootcont; | |
290 | } u; | |
df366c26 MD |
291 | scm_catch_body_t body; |
292 | void *body_data; | |
293 | scm_catch_handler_t handler; | |
294 | void *handler_data; | |
0a1a92ab MD |
295 | } c_launch_data; |
296 | ||
297 | static SCM | |
39752bec | 298 | c_body_bootstrip (c_launch_data* data) |
0a1a92ab MD |
299 | { |
300 | /* First save the new root continuation */ | |
301 | data->u.rootcont = scm_root->rootcont; | |
39752bec | 302 | return (data->body) (data->body_data); |
0a1a92ab MD |
303 | } |
304 | ||
305 | static SCM | |
306 | c_handler_bootstrip (c_launch_data* data, SCM tag, SCM throw_args) | |
307 | { | |
308 | scm_root->rootcont = data->u.rootcont; | |
309 | return (data->handler) (data->handler_data, tag, throw_args); | |
310 | } | |
df366c26 MD |
311 | |
312 | static void | |
313 | c_launch_thread (void *p) | |
314 | { | |
0a1a92ab | 315 | register c_launch_data *data = (c_launch_data *) p; |
df366c26 | 316 | /* The thread object will be GC protected by being on this stack */ |
0a1a92ab | 317 | SCM thread = data->u.thread; |
df366c26 MD |
318 | /* We must use the address of `thread', otherwise the compiler will |
319 | optimize it away. This is OK since the longest SCM_STACKITEM | |
320 | also is a long. */ | |
0a1a92ab MD |
321 | scm_internal_cwdr ((scm_catch_body_t) c_body_bootstrip, |
322 | data, | |
323 | (scm_catch_handler_t) c_handler_bootstrip, | |
324 | data, | |
df366c26 MD |
325 | &thread); |
326 | scm_thread_count--; | |
0a1a92ab | 327 | scm_must_free ((char *) data); |
df366c26 MD |
328 | } |
329 | ||
330 | SCM | |
331 | scm_spawn_thread (scm_catch_body_t body, void *body_data, | |
332 | scm_catch_handler_t handler, void *handler_data) | |
333 | { | |
334 | SCM thread; | |
335 | coop_t *t; | |
336 | SCM root, old_winds; | |
0a1a92ab MD |
337 | c_launch_data *data = (c_launch_data *) scm_must_malloc (sizeof (*data), |
338 | "scm_spawn_thread"); | |
df366c26 MD |
339 | |
340 | /* Unwind wind chain. */ | |
341 | old_winds = scm_dynwinds; | |
342 | scm_dowinds (SCM_EOL, scm_ilength (scm_root->dynwinds)); | |
343 | ||
344 | /* Allocate thread locals. */ | |
345 | root = scm_make_root (scm_root->handle); | |
346 | /* Make thread. */ | |
347 | SCM_NEWCELL (thread); | |
348 | SCM_DEFER_INTS; | |
349 | SCM_SETCAR (thread, scm_tc16_thread); | |
350 | ||
0a1a92ab MD |
351 | data->u.thread = thread; |
352 | data->body = body; | |
353 | data->body_data = body_data; | |
354 | data->handler = handler; | |
355 | data->handler_data = handler_data; | |
df366c26 | 356 | |
0a1a92ab | 357 | t = coop_create (c_launch_thread, (void *) data); |
df366c26 MD |
358 | |
359 | t->data = SCM_ROOT_STATE (root); | |
360 | SCM_SETCDR (thread, t); | |
361 | scm_thread_count++; | |
362 | /* Note that the following statement also could cause coop_yield.*/ | |
363 | SCM_ALLOW_INTS; | |
364 | ||
365 | /* We're now ready for the thread to begin. */ | |
366 | coop_yield(); | |
367 | ||
368 | /* Return to old dynamic context. */ | |
369 | scm_dowinds (old_winds, - scm_ilength (old_winds)); | |
370 | ||
371 | return thread; | |
372 | } | |
373 | ||
7bfd3b9e JB |
374 | SCM |
375 | scm_join_thread (SCM t) | |
0c95b57d | 376 | #define FUNC_NAME s_join_thread |
7bfd3b9e | 377 | { |
3b3b36dd | 378 | SCM_VALIDATE_THREAD (1,t); |
7bfd3b9e JB |
379 | coop_join (SCM_THREAD_DATA (t)); |
380 | return SCM_BOOL_T; | |
381 | } | |
0c95b57d | 382 | #undef FUNC_NAME |
7bfd3b9e | 383 | |
7bfd3b9e | 384 | SCM |
0c95b57d | 385 | scm_yield (void) |
7bfd3b9e JB |
386 | { |
387 | /* Yield early */ | |
388 | scm_switch_counter = SCM_THREAD_SWITCH_COUNT; | |
389 | coop_yield(); | |
390 | ||
391 | return SCM_BOOL_T; | |
392 | } | |
393 | ||
7bfd3b9e | 394 | SCM |
0c95b57d | 395 | scm_single_thread_p (void) |
7bfd3b9e JB |
396 | { |
397 | return (coop_global_runq.tail == &coop_global_runq.t | |
398 | ? SCM_BOOL_T | |
399 | : SCM_BOOL_F); | |
400 | } | |
401 | ||
7bfd3b9e | 402 | SCM |
0c95b57d | 403 | scm_make_mutex (void) |
7bfd3b9e JB |
404 | { |
405 | SCM m; | |
406 | coop_m *data = (coop_m *) scm_must_malloc (sizeof (coop_m), "mutex"); | |
23a62151 MD |
407 | |
408 | SCM_NEWSMOB (m, scm_tc16_mutex, data); | |
7bfd3b9e JB |
409 | coop_mutex_init (data); |
410 | return m; | |
411 | } | |
412 | ||
7bfd3b9e JB |
413 | SCM |
414 | scm_lock_mutex (SCM m) | |
7bfd3b9e | 415 | { |
cabe682c | 416 | SCM_ASSERT (SCM_MUTEXP (m), m, SCM_ARG1, s_lock_mutex); |
7bfd3b9e JB |
417 | coop_mutex_lock (SCM_MUTEX_DATA (m)); |
418 | return SCM_BOOL_T; | |
419 | } | |
420 | ||
7bfd3b9e JB |
421 | SCM |
422 | scm_unlock_mutex (SCM m) | |
7bfd3b9e | 423 | { |
0c95b57d | 424 | SCM_ASSERT (SCM_MUTEXP (m), m, SCM_ARG1, s_unlock_mutex); |
7bfd3b9e JB |
425 | coop_mutex_unlock(SCM_MUTEX_DATA (m)); |
426 | ||
427 | /* Yield early */ | |
428 | scm_switch_counter = SCM_THREAD_SWITCH_COUNT; | |
429 | coop_yield(); | |
430 | ||
431 | return SCM_BOOL_T; | |
432 | } | |
433 | ||
7bfd3b9e | 434 | SCM |
0c95b57d | 435 | scm_make_condition_variable (void) |
7bfd3b9e JB |
436 | { |
437 | SCM c; | |
438 | coop_c *data = (coop_c *) scm_must_malloc (sizeof (coop_c), "condvar"); | |
23a62151 | 439 | SCM_NEWSMOB (c, scm_tc16_condvar, data); |
7bfd3b9e JB |
440 | coop_condition_variable_init (SCM_CONDVAR_DATA (c)); |
441 | return c; | |
442 | } | |
443 | ||
7bfd3b9e JB |
444 | SCM |
445 | scm_wait_condition_variable (SCM c, SCM m) | |
7bfd3b9e | 446 | { |
0c95b57d | 447 | SCM_ASSERT (SCM_CONDVARP (c), |
7bfd3b9e JB |
448 | c, |
449 | SCM_ARG1, | |
450 | s_wait_condition_variable); | |
0c95b57d | 451 | SCM_ASSERT (SCM_MUTEXP (m), |
7bfd3b9e JB |
452 | m, |
453 | SCM_ARG2, | |
454 | s_wait_condition_variable); | |
c8bf4ecd MD |
455 | coop_condition_variable_wait_mutex (SCM_CONDVAR_DATA (c), |
456 | SCM_MUTEX_DATA (m)); | |
7bfd3b9e JB |
457 | return SCM_BOOL_T; |
458 | } | |
459 | ||
7bfd3b9e JB |
460 | SCM |
461 | scm_signal_condition_variable (SCM c) | |
7bfd3b9e | 462 | { |
0c95b57d | 463 | SCM_ASSERT (SCM_CONDVARP (c), |
7bfd3b9e JB |
464 | c, |
465 | SCM_ARG1, | |
466 | s_signal_condition_variable); | |
467 | coop_condition_variable_signal (SCM_CONDVAR_DATA (c)); | |
468 | return SCM_BOOL_T; | |
469 | } |