fix msvc build.
[mono/afaerber.git] / libgc / win32_threads.c
bloba2cd0fda43ee3dbd88bf8d15884bc76c1f35c750
1 #include "private/gc_priv.h"
3 #if defined(GC_WIN32_THREADS)
5 #include <windows.h>
7 #ifdef CYGWIN32
8 # include <errno.h>
10 /* Cygwin-specific forward decls */
11 # undef pthread_create
12 # undef pthread_sigmask
13 # undef pthread_join
14 # undef pthread_detach
15 # undef dlopen
17 # define DEBUG_CYGWIN_THREADS 0
19 void * GC_start_routine(void * arg);
20 void GC_thread_exit_proc(void *arg);
22 #endif
24 /* The type of the first argument to InterlockedExchange. */
25 /* Documented to be LONG volatile *, but at least gcc likes */
26 /* this better. */
27 typedef LONG * IE_t;
29 #ifndef MAX_THREADS
30 # define MAX_THREADS 256
31 /* FIXME: */
32 /* Things may get quite slow for large numbers of threads, */
33 /* since we look them up with sequential search. */
34 #endif
36 GC_bool GC_thr_initialized = FALSE;
38 DWORD GC_main_thread = 0;
40 struct GC_thread_Rep {
41 LONG in_use; /* Updated without lock. */
42 /* We assert that unused */
43 /* entries have invalid ids of */
44 /* zero and zero stack fields. */
45 DWORD id;
46 HANDLE handle;
47 ptr_t stack_base; /* The cold end of the stack. */
48 /* 0 ==> entry not valid. */
49 /* !in_use ==> stack_base == 0 */
50 GC_bool suspended;
52 # ifdef CYGWIN32
53 void *status; /* hold exit value until join in case it's a pointer */
54 pthread_t pthread_id;
55 short flags; /* Protected by GC lock. */
56 # define FINISHED 1 /* Thread has exited. */
57 # define DETACHED 2 /* Thread is intended to be detached. */
58 # endif
61 typedef volatile struct GC_thread_Rep * GC_thread;
64 * We generally assume that volatile ==> memory ordering, at least among
65 * volatiles.
68 volatile GC_bool GC_please_stop = FALSE;
70 volatile struct GC_thread_Rep thread_table[MAX_THREADS];
72 volatile LONG GC_max_thread_index = 0; /* Largest index in thread_table */
73 /* that was ever used. */
75 extern LONG WINAPI GC_write_fault_handler(struct _EXCEPTION_POINTERS *exc_info);
77 int GC_thread_is_registered (void)
79 #if defined(GC_DLL) || defined(GC_INSIDE_DLL)
80 /* Registered by DllMain */
81 return 1;
82 #else
83 /* FIXME: */
84 return 0;
85 #endif
89 * This may be called from DllMain, and hence operates under unusual
90 * constraints.
92 static GC_thread GC_new_thread(void) {
93 int i;
94 /* It appears to be unsafe to acquire a lock here, since this */
95 /* code is apparently not preeemptible on some systems. */
96 /* (This is based on complaints, not on Microsoft's official */
97 /* documentation, which says this should perform "only simple */
98 /* initialization tasks".) */
99 /* Hence we make do with nonblocking synchronization. */
101 /* The following should be a noop according to the win32 */
102 /* documentation. There is empirical evidence that it */
103 /* isn't. - HB */
104 # if defined(MPROTECT_VDB)
105 if (GC_incremental) SetUnhandledExceptionFilter(GC_write_fault_handler);
106 # endif
107 /* cast away volatile qualifier */
108 for (i = 0; InterlockedExchange((IE_t)&thread_table[i].in_use,1) != 0; i++) {
109 /* Compare-and-swap would make this cleaner, but that's not */
110 /* supported before Windows 98 and NT 4.0. In Windows 2000, */
111 /* InterlockedExchange is supposed to be replaced by */
112 /* InterlockedExchangePointer, but that's not really what I */
113 /* want here. */
114 if (i == MAX_THREADS - 1)
115 ABORT("too many threads");
117 /* Update GC_max_thread_index if necessary. The following is safe, */
118 /* and unlike CompareExchange-based solutions seems to work on all */
119 /* Windows95 and later platforms. */
120 /* Unfortunately, GC_max_thread_index may be temporarily out of */
121 /* bounds, so readers have to compensate. */
122 while (i > GC_max_thread_index) {
123 InterlockedIncrement((IE_t)&GC_max_thread_index);
125 if (GC_max_thread_index >= MAX_THREADS) {
126 /* We overshot due to simultaneous increments. */
127 /* Setting it to MAX_THREADS-1 is always safe. */
128 GC_max_thread_index = MAX_THREADS - 1;
131 # ifdef CYGWIN32
132 thread_table[i].pthread_id = pthread_self();
133 # endif
134 if (!DuplicateHandle(GetCurrentProcess(),
135 GetCurrentThread(),
136 GetCurrentProcess(),
137 (HANDLE*)&thread_table[i].handle,
140 DUPLICATE_SAME_ACCESS)) {
141 DWORD last_error = GetLastError();
142 GC_printf1("Last error code: %lx\n", last_error);
143 ABORT("DuplicateHandle failed");
145 thread_table[i].stack_base = GC_get_stack_base();
146 /* Up until this point, GC_push_all_stacks considers this thread */
147 /* invalid. */
148 if (thread_table[i].stack_base == NULL)
149 ABORT("Failed to find stack base in GC_new_thread");
150 /* Up until this point, this entry is viewed as reserved but invalid */
151 /* by GC_delete_thread. */
152 thread_table[i].id = GetCurrentThreadId();
153 /* If this thread is being created while we are trying to stop */
154 /* the world, wait here. Hopefully this can't happen on any */
155 /* systems that don't allow us to block here. */
156 while (GC_please_stop) Sleep(20);
157 return thread_table + i;
161 * GC_max_thread_index may temporarily be larger than MAX_THREADS.
162 * To avoid subscript errors, we check on access.
164 #ifdef __GNUC__
165 __inline__
166 #endif
167 LONG GC_get_max_thread_index()
169 LONG my_max = GC_max_thread_index;
171 if (my_max >= MAX_THREADS) return MAX_THREADS-1;
172 return my_max;
175 /* This is intended to be lock-free, though that */
176 /* assumes that the CloseHandle becomes visible before the */
177 /* in_use assignment. */
178 static void GC_delete_gc_thread(GC_thread thr)
180 CloseHandle(thr->handle);
181 /* cast away volatile qualifier */
182 thr->stack_base = 0;
183 thr->id = 0;
184 # ifdef CYGWIN32
185 thr->pthread_id = 0;
186 # endif /* CYGWIN32 */
187 thr->in_use = FALSE;
190 static void GC_delete_thread(DWORD thread_id) {
191 int i;
192 LONG my_max = GC_get_max_thread_index();
194 for (i = 0;
195 i <= my_max &&
196 (!thread_table[i].in_use || thread_table[i].id != thread_id);
197 /* Must still be in_use, since nobody else can store our thread_id. */
198 i++) {}
199 if (i > my_max) {
200 WARN("Removing nonexistent thread %ld\n", (GC_word)thread_id);
201 } else {
202 GC_delete_gc_thread(thread_table+i);
207 #ifdef CYGWIN32
209 /* Return a GC_thread corresponding to a given pthread_t. */
210 /* Returns 0 if it's not there. */
211 /* We assume that this is only called for pthread ids that */
212 /* have not yet terminated or are still joinable. */
213 static GC_thread GC_lookup_thread(pthread_t id)
215 int i;
216 LONG my_max = GC_get_max_thread_index();
218 for (i = 0;
219 i <= my_max &&
220 (!thread_table[i].in_use || thread_table[i].pthread_id != id
221 || !thread_table[i].in_use);
222 /* Must still be in_use, since nobody else can store our thread_id. */
223 i++);
224 if (i > my_max) return 0;
225 return thread_table + i;
228 #endif /* CYGWIN32 */
230 void GC_push_thread_structures GC_PROTO((void))
232 /* Unlike the other threads implementations, the thread table here */
233 /* contains no pointers to the collectable heap. Thus we have */
234 /* no private structures we need to preserve. */
235 # ifdef CYGWIN32
236 { int i; /* pthreads may keep a pointer in the thread exit value */
237 LONG my_max = GC_get_max_thread_index();
239 for (i = 0; i <= my_max; i++)
240 if (thread_table[i].in_use)
241 GC_push_all((ptr_t)&(thread_table[i].status),
242 (ptr_t)(&(thread_table[i].status)+1));
244 # endif
247 /* Defined in misc.c */
248 extern CRITICAL_SECTION GC_write_cs;
250 void GC_stop_world()
252 DWORD thread_id = GetCurrentThreadId();
253 int i;
255 if (!GC_thr_initialized) ABORT("GC_stop_world() called before GC_thr_init()");
257 GC_please_stop = TRUE;
258 # ifndef CYGWIN32
259 EnterCriticalSection(&GC_write_cs);
260 # endif /* !CYGWIN32 */
261 for (i = 0; i <= GC_get_max_thread_index(); i++)
262 if (thread_table[i].stack_base != 0
263 && thread_table[i].id != thread_id) {
264 # ifdef MSWINCE
265 /* SuspendThread will fail if thread is running kernel code */
266 while (SuspendThread(thread_table[i].handle) == (DWORD)-1)
267 Sleep(10);
268 # else
269 /* Apparently the Windows 95 GetOpenFileName call creates */
270 /* a thread that does not properly get cleaned up, and */
271 /* SuspendThread on its descriptor may provoke a crash. */
272 /* This reduces the probability of that event, though it still */
273 /* appears there's a race here. */
274 DWORD exitCode;
275 if (GetExitCodeThread(thread_table[i].handle,&exitCode) &&
276 exitCode != STILL_ACTIVE) {
277 thread_table[i].stack_base = 0; /* prevent stack from being pushed */
278 # ifndef CYGWIN32
279 /* this breaks pthread_join on Cygwin, which is guaranteed to */
280 /* only see user pthreads */
281 thread_table[i].in_use = FALSE;
282 CloseHandle(thread_table[i].handle);
283 # endif
284 continue;
286 if (SuspendThread(thread_table[i].handle) == (DWORD)-1) {
287 thread_table[i].stack_base = 0; /* prevent stack from being pushed */
288 # ifndef CYGWIN32
289 /* this breaks pthread_join on Cygwin, which is guaranteed to */
290 /* only see user pthreads */
291 thread_table[i].in_use = FALSE;
292 CloseHandle(thread_table[i].handle);
293 # endif
295 # endif
296 thread_table[i].suspended = TRUE;
298 # ifndef CYGWIN32
299 LeaveCriticalSection(&GC_write_cs);
300 # endif /* !CYGWIN32 */
303 void GC_start_world()
305 DWORD thread_id = GetCurrentThreadId();
306 int i;
307 LONG my_max = GC_get_max_thread_index();
309 for (i = 0; i <= my_max; i++)
310 if (thread_table[i].stack_base != 0 && thread_table[i].suspended
311 && thread_table[i].id != thread_id) {
312 if (ResumeThread(thread_table[i].handle) == (DWORD)-1)
313 ABORT("ResumeThread failed");
314 thread_table[i].suspended = FALSE;
316 GC_please_stop = FALSE;
319 # ifdef _MSC_VER
320 # pragma warning(disable:4715)
321 # endif
322 ptr_t GC_current_stackbottom()
324 DWORD thread_id = GetCurrentThreadId();
325 int i;
326 LONG my_max = GC_get_max_thread_index();
328 for (i = 0; i <= my_max; i++)
329 if (thread_table[i].stack_base && thread_table[i].id == thread_id)
330 return thread_table[i].stack_base;
331 ABORT("no thread table entry for current thread");
333 # ifdef _MSC_VER
334 # pragma warning(default:4715)
335 # endif
337 # ifdef MSWINCE
338 /* The VirtualQuery calls below won't work properly on WinCE, but */
339 /* since each stack is restricted to an aligned 64K region of */
340 /* virtual memory we can just take the next lowest multiple of 64K. */
341 # define GC_get_stack_min(s) \
342 ((ptr_t)(((DWORD)(s) - 1) & 0xFFFF0000))
343 # else
344 static ptr_t GC_get_stack_min(ptr_t s)
346 ptr_t bottom;
347 MEMORY_BASIC_INFORMATION info;
348 VirtualQuery(s, &info, sizeof(info));
349 do {
350 bottom = info.BaseAddress;
351 VirtualQuery(bottom - 1, &info, sizeof(info));
352 } while ((info.Protect & PAGE_READWRITE)
353 && !(info.Protect & PAGE_GUARD));
354 return(bottom);
356 # endif
358 void GC_push_all_stacks()
360 DWORD thread_id = GetCurrentThreadId();
361 GC_bool found_me = FALSE;
362 int i;
363 int dummy;
364 ptr_t sp, stack_min;
365 GC_thread thread;
366 LONG my_max = GC_get_max_thread_index();
368 for (i = 0; i <= my_max; i++) {
369 thread = thread_table + i;
370 if (thread -> in_use && thread -> stack_base) {
371 if (thread -> id == thread_id) {
372 sp = (ptr_t) &dummy;
373 found_me = TRUE;
374 } else {
375 CONTEXT context;
376 context.ContextFlags = CONTEXT_INTEGER|CONTEXT_CONTROL;
377 if (!GetThreadContext(thread_table[i].handle, &context))
378 ABORT("GetThreadContext failed");
380 /* Push all registers that might point into the heap. Frame */
381 /* pointer registers are included in case client code was */
382 /* compiled with the 'omit frame pointer' optimisation. */
383 # define PUSH1(reg) GC_push_one((word)context.reg)
384 # define PUSH2(r1,r2) PUSH1(r1), PUSH1(r2)
385 # define PUSH4(r1,r2,r3,r4) PUSH2(r1,r2), PUSH2(r3,r4)
386 # if defined(I386)
387 PUSH4(Edi,Esi,Ebx,Edx), PUSH2(Ecx,Eax), PUSH1(Ebp);
388 sp = (ptr_t)context.Esp;
389 # elif defined(X86_64)
390 PUSH4(Rax,Rcx,Rdx,Rbx); PUSH2(Rbp, Rsi); PUSH1(Rdi);
391 PUSH4(R8, R9, R10, R11); PUSH4(R12, R13, R14, R15);
392 sp = (ptr_t)context.Rsp;
393 # elif defined(ARM32)
394 PUSH4(R0,R1,R2,R3),PUSH4(R4,R5,R6,R7),PUSH4(R8,R9,R10,R11),PUSH1(R12);
395 sp = (ptr_t)context.Sp;
396 # elif defined(SHx)
397 PUSH4(R0,R1,R2,R3), PUSH4(R4,R5,R6,R7), PUSH4(R8,R9,R10,R11);
398 PUSH2(R12,R13), PUSH1(R14);
399 sp = (ptr_t)context.R15;
400 # elif defined(MIPS)
401 PUSH4(IntAt,IntV0,IntV1,IntA0), PUSH4(IntA1,IntA2,IntA3,IntT0);
402 PUSH4(IntT1,IntT2,IntT3,IntT4), PUSH4(IntT5,IntT6,IntT7,IntS0);
403 PUSH4(IntS1,IntS2,IntS3,IntS4), PUSH4(IntS5,IntS6,IntS7,IntT8);
404 PUSH4(IntT9,IntK0,IntK1,IntS8);
405 sp = (ptr_t)context.IntSp;
406 # elif defined(PPC)
407 PUSH4(Gpr0, Gpr3, Gpr4, Gpr5), PUSH4(Gpr6, Gpr7, Gpr8, Gpr9);
408 PUSH4(Gpr10,Gpr11,Gpr12,Gpr14), PUSH4(Gpr15,Gpr16,Gpr17,Gpr18);
409 PUSH4(Gpr19,Gpr20,Gpr21,Gpr22), PUSH4(Gpr23,Gpr24,Gpr25,Gpr26);
410 PUSH4(Gpr27,Gpr28,Gpr29,Gpr30), PUSH1(Gpr31);
411 sp = (ptr_t)context.Gpr1;
412 # elif defined(ALPHA)
413 PUSH4(IntV0,IntT0,IntT1,IntT2), PUSH4(IntT3,IntT4,IntT5,IntT6);
414 PUSH4(IntT7,IntS0,IntS1,IntS2), PUSH4(IntS3,IntS4,IntS5,IntFp);
415 PUSH4(IntA0,IntA1,IntA2,IntA3), PUSH4(IntA4,IntA5,IntT8,IntT9);
416 PUSH4(IntT10,IntT11,IntT12,IntAt);
417 sp = (ptr_t)context.IntSp;
418 # else
419 # error "architecture is not supported"
420 # endif
423 stack_min = GC_get_stack_min(thread->stack_base);
425 if (sp >= stack_min && sp < thread->stack_base)
426 GC_push_all_stack(sp, thread->stack_base);
427 else {
428 WARN("Thread stack pointer 0x%lx out of range, pushing everything\n",
429 (unsigned long)sp);
430 GC_push_all_stack(stack_min, thread->stack_base);
434 if (!found_me) ABORT("Collecting from unknown thread.");
437 void GC_get_next_stack(char *start, char **lo, char **hi)
439 int i;
440 # define ADDR_LIMIT (char *)(-1L)
441 char * current_min = ADDR_LIMIT;
442 LONG my_max = GC_get_max_thread_index();
444 for (i = 0; i <= my_max; i++) {
445 char * s = (char *)thread_table[i].stack_base;
447 if (0 != s && s > start && s < current_min) {
448 current_min = s;
451 *hi = current_min;
452 if (current_min == ADDR_LIMIT) {
453 *lo = ADDR_LIMIT;
454 return;
456 *lo = GC_get_stack_min(current_min);
457 if (*lo < start) *lo = start;
460 #if !defined(CYGWIN32)
462 #if !defined(MSWINCE) && defined(GC_DLL)
464 /* We register threads from DllMain */
466 GC_API HANDLE WINAPI GC_CreateThread(
467 LPSECURITY_ATTRIBUTES lpThreadAttributes,
468 DWORD dwStackSize, LPTHREAD_START_ROUTINE lpStartAddress,
469 LPVOID lpParameter, DWORD dwCreationFlags, LPDWORD lpThreadId )
471 return CreateThread(lpThreadAttributes, dwStackSize, lpStartAddress,
472 lpParameter, dwCreationFlags, lpThreadId);
475 #else /* defined(MSWINCE) || !defined(GC_DLL)) */
477 /* We have no DllMain to take care of new threads. Thus we */
478 /* must properly intercept thread creation. */
480 typedef struct {
481 LPTHREAD_START_ROUTINE start;
482 LPVOID param;
483 } thread_args;
485 static DWORD WINAPI thread_start(LPVOID arg);
487 GC_API HANDLE WINAPI GC_CreateThread(
488 LPSECURITY_ATTRIBUTES lpThreadAttributes,
489 DWORD dwStackSize, LPTHREAD_START_ROUTINE lpStartAddress,
490 LPVOID lpParameter, DWORD dwCreationFlags, LPDWORD lpThreadId )
492 HANDLE thread_h = NULL;
494 thread_args *args;
496 if (!GC_is_initialized) GC_init();
497 /* make sure GC is initialized (i.e. main thread is attached) */
499 args = GC_malloc_uncollectable(sizeof(thread_args));
500 /* Handed off to and deallocated by child thread. */
501 if (0 == args) {
502 SetLastError(ERROR_NOT_ENOUGH_MEMORY);
503 return NULL;
506 /* set up thread arguments */
507 args -> start = lpStartAddress;
508 args -> param = lpParameter;
510 thread_h = CreateThread(lpThreadAttributes,
511 dwStackSize, thread_start,
512 args, dwCreationFlags,
513 lpThreadId);
515 return thread_h;
518 static DWORD WINAPI thread_start(LPVOID arg)
520 DWORD ret = 0;
521 thread_args *args = (thread_args *)arg;
523 GC_new_thread();
525 /* Clear the thread entry even if we exit with an exception. */
526 /* This is probably pointless, since an uncaught exception is */
527 /* supposed to result in the process being killed. */
528 #ifndef __GNUC__
529 __try {
530 #endif /* __GNUC__ */
531 ret = args->start (args->param);
532 #ifndef __GNUC__
533 } __finally {
534 #endif /* __GNUC__ */
535 GC_free(args);
536 GC_delete_thread(GetCurrentThreadId());
537 #ifndef __GNUC__
539 #endif /* __GNUC__ */
541 return ret;
543 #endif /* !defined(MSWINCE) && !(defined(__MINGW32__) && !defined(_DLL)) */
545 #endif /* !CYGWIN32 */
547 #ifdef MSWINCE
549 typedef struct {
550 HINSTANCE hInstance;
551 HINSTANCE hPrevInstance;
552 LPWSTR lpCmdLine;
553 int nShowCmd;
554 } main_thread_args;
556 DWORD WINAPI main_thread_start(LPVOID arg);
558 int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,
559 LPWSTR lpCmdLine, int nShowCmd)
561 DWORD exit_code = 1;
563 main_thread_args args = {
564 hInstance, hPrevInstance, lpCmdLine, nShowCmd
566 HANDLE thread_h;
567 DWORD thread_id;
569 /* initialize everything */
570 GC_init();
572 /* start the main thread */
573 thread_h = GC_CreateThread(
574 NULL, 0, main_thread_start, &args, 0, &thread_id);
576 if (thread_h != NULL)
578 WaitForSingleObject (thread_h, INFINITE);
579 GetExitCodeThread (thread_h, &exit_code);
580 CloseHandle (thread_h);
583 GC_deinit();
584 DeleteCriticalSection(&GC_allocate_ml);
586 return (int) exit_code;
589 DWORD WINAPI main_thread_start(LPVOID arg)
591 main_thread_args * args = (main_thread_args *) arg;
593 return (DWORD) GC_WinMain (args->hInstance, args->hPrevInstance,
594 args->lpCmdLine, args->nShowCmd);
597 # else /* !MSWINCE */
599 /* Called by GC_init() - we hold the allocation lock. */
600 void GC_thr_init() {
601 if (GC_thr_initialized) return;
602 GC_main_thread = GetCurrentThreadId();
603 GC_thr_initialized = TRUE;
605 /* Add the initial thread, so we can stop it. */
606 GC_new_thread();
609 #ifdef CYGWIN32
611 struct start_info {
612 void *(*start_routine)(void *);
613 void *arg;
614 GC_bool detached;
617 int GC_pthread_join(pthread_t pthread_id, void **retval) {
618 int result;
619 int i;
620 GC_thread me;
622 # if DEBUG_CYGWIN_THREADS
623 GC_printf3("thread 0x%x(0x%x) is joining thread 0x%x.\n",
624 (int)pthread_self(), GetCurrentThreadId(), (int)pthread_id);
625 # endif
627 /* Thread being joined might not have registered itself yet. */
628 /* After the join,thread id may have been recycled. */
629 /* FIXME: It would be better if this worked more like */
630 /* pthread_support.c. */
632 while ((me = GC_lookup_thread(pthread_id)) == 0) Sleep(10);
634 result = pthread_join(pthread_id, retval);
636 GC_delete_gc_thread(me);
638 # if DEBUG_CYGWIN_THREADS
639 GC_printf3("thread 0x%x(0x%x) completed join with thread 0x%x.\n",
640 (int)pthread_self(), GetCurrentThreadId(), (int)pthread_id);
641 # endif
643 return result;
646 /* Cygwin-pthreads calls CreateThread internally, but it's not
647 * easily interceptible by us..
648 * so intercept pthread_create instead
651 GC_pthread_create(pthread_t *new_thread,
652 const pthread_attr_t *attr,
653 void *(*start_routine)(void *), void *arg) {
654 int result;
655 struct start_info * si;
657 if (!GC_is_initialized) GC_init();
658 /* make sure GC is initialized (i.e. main thread is attached) */
660 /* This is otherwise saved only in an area mmapped by the thread */
661 /* library, which isn't visible to the collector. */
662 si = GC_malloc_uncollectable(sizeof(struct start_info));
663 if (0 == si) return(EAGAIN);
665 si -> start_routine = start_routine;
666 si -> arg = arg;
667 if (attr != 0 &&
668 pthread_attr_getdetachstate(attr, &si->detached)
669 == PTHREAD_CREATE_DETACHED) {
670 si->detached = TRUE;
673 # if DEBUG_CYGWIN_THREADS
674 GC_printf2("About to create a thread from 0x%x(0x%x)\n",
675 (int)pthread_self(), GetCurrentThreadId);
676 # endif
677 result = pthread_create(new_thread, attr, GC_start_routine, si);
679 if (result) { /* failure */
680 GC_free(si);
683 return(result);
686 void * GC_start_routine(void * arg)
688 struct start_info * si = arg;
689 void * result;
690 void *(*start)(void *);
691 void *start_arg;
692 pthread_t pthread_id;
693 GC_thread me;
694 GC_bool detached;
695 int i;
697 # if DEBUG_CYGWIN_THREADS
698 GC_printf2("thread 0x%x(0x%x) starting...\n",(int)pthread_self(),
699 GetCurrentThreadId());
700 # endif
702 /* If a GC occurs before the thread is registered, that GC will */
703 /* ignore this thread. That's fine, since it will block trying to */
704 /* acquire the allocation lock, and won't yet hold interesting */
705 /* pointers. */
706 LOCK();
707 /* We register the thread here instead of in the parent, so that */
708 /* we don't need to hold the allocation lock during pthread_create. */
709 me = GC_new_thread();
710 UNLOCK();
712 start = si -> start_routine;
713 start_arg = si -> arg;
714 if (si-> detached) me -> flags |= DETACHED;
715 me -> pthread_id = pthread_id = pthread_self();
717 GC_free(si); /* was allocated uncollectable */
719 pthread_cleanup_push(GC_thread_exit_proc, (void *)me);
720 result = (*start)(start_arg);
721 me -> status = result;
722 pthread_cleanup_pop(0);
724 # if DEBUG_CYGWIN_THREADS
725 GC_printf2("thread 0x%x(0x%x) returned from start routine.\n",
726 (int)pthread_self(),GetCurrentThreadId());
727 # endif
729 return(result);
732 void GC_thread_exit_proc(void *arg)
734 GC_thread me = (GC_thread)arg;
735 int i;
737 # if DEBUG_CYGWIN_THREADS
738 GC_printf2("thread 0x%x(0x%x) called pthread_exit().\n",
739 (int)pthread_self(),GetCurrentThreadId());
740 # endif
742 LOCK();
743 if (me -> flags & DETACHED) {
744 GC_delete_thread(GetCurrentThreadId());
745 } else {
746 /* deallocate it as part of join */
747 me -> flags |= FINISHED;
749 UNLOCK();
752 /* nothing required here... */
753 int GC_pthread_sigmask(int how, const sigset_t *set, sigset_t *oset) {
754 return pthread_sigmask(how, set, oset);
757 int GC_pthread_detach(pthread_t thread)
759 int result;
760 GC_thread thread_gc_id;
762 LOCK();
763 thread_gc_id = GC_lookup_thread(thread);
764 UNLOCK();
765 result = pthread_detach(thread);
766 if (result == 0) {
767 LOCK();
768 thread_gc_id -> flags |= DETACHED;
769 /* Here the pthread thread id may have been recycled. */
770 if (thread_gc_id -> flags & FINISHED) {
771 GC_delete_gc_thread(thread_gc_id);
773 UNLOCK();
775 return result;
778 #else /* !CYGWIN32 */
781 * We avoid acquiring locks here, since this doesn't seem to be preemptable.
782 * Pontus Rydin suggests wrapping the thread start routine instead.
784 #if defined(GC_DLL) || defined(GC_INSIDE_DLL)
785 BOOL WINAPI GC_DllMain(HINSTANCE inst, ULONG reason, LPVOID reserved)
787 switch (reason) {
788 case DLL_PROCESS_ATTACH:
789 GC_init(); /* Force initialization before thread attach. */
790 /* fall through */
791 case DLL_THREAD_ATTACH:
792 GC_ASSERT(GC_thr_initialized);
793 if (GC_main_thread != GetCurrentThreadId()) {
794 GC_new_thread();
795 } /* o.w. we already did it during GC_thr_init(), called by GC_init() */
796 break;
798 case DLL_THREAD_DETACH:
799 GC_delete_thread(GetCurrentThreadId());
800 break;
802 case DLL_PROCESS_DETACH:
804 int i;
806 LOCK();
807 for (i = 0; i <= GC_get_max_thread_index(); ++i)
809 if (thread_table[i].in_use)
810 GC_delete_gc_thread(thread_table + i);
812 UNLOCK();
814 GC_deinit();
815 DeleteCriticalSection(&GC_allocate_ml);
817 break;
820 return TRUE;
822 #endif /* GC_DLL */
823 #endif /* !CYGWIN32 */
825 # endif /* !MSWINCE */
827 #endif /* GC_WIN32_THREADS */