blob: 2de1c6953b870f1a1df07927f87da32dd43e0fde [file] [log] [blame]
#include "private/gc_priv.h"
#if defined(GC_WIN32_THREADS)
#include <windows.h>
#ifdef CYGWIN32
# include <errno.h>
/* Cygwin-specific forward decls */
# undef pthread_create
# undef pthread_sigmask
# undef pthread_join
# undef pthread_detach
# undef dlopen
# define DEBUG_CYGWIN_THREADS 0
void * GC_start_routine(void * arg);
void GC_thread_exit_proc(void *arg);
#endif
/* The type of the first argument to InterlockedExchange. */
/* Documented to be LONG volatile *, but at least gcc likes */
/* this better. */
typedef LONG * IE_t;
#ifndef MAX_THREADS
# define MAX_THREADS 256
/* FIXME: */
/* Things may get quite slow for large numbers of threads, */
/* since we look them up with sequential search. */
#endif
GC_bool GC_thr_initialized = FALSE;
DWORD GC_main_thread = 0;
struct GC_thread_Rep {
LONG in_use; /* Updated without lock. */
/* We assert that unused */
/* entries have invalid ids of */
/* zero and zero stack fields. */
DWORD id;
HANDLE handle;
ptr_t stack_base; /* The cold end of the stack. */
/* 0 ==> entry not valid. */
/* !in_use ==> stack_base == 0 */
GC_bool suspended;
# ifdef CYGWIN32
void *status; /* hold exit value until join in case it's a pointer */
pthread_t pthread_id;
short flags; /* Protected by GC lock. */
# define FINISHED 1 /* Thread has exited. */
# define DETACHED 2 /* Thread is intended to be detached. */
# endif
};
typedef volatile struct GC_thread_Rep * GC_thread;
/*
* We generally assume that volatile ==> memory ordering, at least among
* volatiles.
*/
volatile GC_bool GC_please_stop = FALSE;
volatile struct GC_thread_Rep thread_table[MAX_THREADS];
volatile LONG GC_max_thread_index = 0; /* Largest index in thread_table */
/* that was ever used. */
extern LONG WINAPI GC_write_fault_handler(struct _EXCEPTION_POINTERS *exc_info);
/*
* This may be called from DllMain, and hence operates under unusual
* constraints.
*/
static GC_thread GC_new_thread(void) {
int i;
/* It appears to be unsafe to acquire a lock here, since this */
/* code is apparently not preeemptible on some systems. */
/* (This is based on complaints, not on Microsoft's official */
/* documentation, which says this should perform "only simple */
/* initialization tasks".) */
/* Hence we make do with nonblocking synchronization. */
/* The following should be a noop according to the win32 */
/* documentation. There is empirical evidence that it */
/* isn't. - HB */
# if defined(MPROTECT_VDB)
if (GC_incremental) SetUnhandledExceptionFilter(GC_write_fault_handler);
# endif
/* cast away volatile qualifier */
for (i = 0; InterlockedExchange((IE_t)&thread_table[i].in_use,1) != 0; i++) {
/* Compare-and-swap would make this cleaner, but that's not */
/* supported before Windows 98 and NT 4.0. In Windows 2000, */
/* InterlockedExchange is supposed to be replaced by */
/* InterlockedExchangePointer, but that's not really what I */
/* want here. */
if (i == MAX_THREADS - 1)
ABORT("too many threads");
}
/* Update GC_max_thread_index if necessary. The following is safe, */
/* and unlike CompareExchange-based solutions seems to work on all */
/* Windows95 and later platforms. */
/* Unfortunately, GC_max_thread_index may be temporarily out of */
/* bounds, so readers have to compensate. */
while (i > GC_max_thread_index) {
InterlockedIncrement((IE_t)&GC_max_thread_index);
}
if (GC_max_thread_index >= MAX_THREADS) {
/* We overshot due to simultaneous increments. */
/* Setting it to MAX_THREADS-1 is always safe. */
GC_max_thread_index = MAX_THREADS - 1;
}
# ifdef CYGWIN32
thread_table[i].pthread_id = pthread_self();
# endif
if (!DuplicateHandle(GetCurrentProcess(),
GetCurrentThread(),
GetCurrentProcess(),
(HANDLE*)&thread_table[i].handle,
0,
0,
DUPLICATE_SAME_ACCESS)) {
DWORD last_error = GetLastError();
GC_printf1("Last error code: %lx\n", last_error);
ABORT("DuplicateHandle failed");
}
thread_table[i].stack_base = GC_get_stack_base();
/* Up until this point, GC_push_all_stacks considers this thread */
/* invalid. */
if (thread_table[i].stack_base == NULL)
ABORT("Failed to find stack base in GC_new_thread");
/* Up until this point, this entry is viewed as reserved but invalid */
/* by GC_delete_thread. */
thread_table[i].id = GetCurrentThreadId();
/* If this thread is being created while we are trying to stop */
/* the world, wait here. Hopefully this can't happen on any */
/* systems that don't allow us to block here. */
while (GC_please_stop) Sleep(20);
return thread_table + i;
}
/*
* GC_max_thread_index may temporarily be larger than MAX_THREADS.
* To avoid subscript errors, we check on access.
*/
#ifdef __GNUC__
__inline__
#endif
LONG GC_get_max_thread_index()
{
LONG my_max = GC_max_thread_index;
if (my_max >= MAX_THREADS) return MAX_THREADS-1;
return my_max;
}
/* This is intended to be lock-free, though that */
/* assumes that the CloseHandle becomes visible before the */
/* in_use assignment. */
static void GC_delete_gc_thread(GC_thread thr)
{
CloseHandle(thr->handle);
/* cast away volatile qualifier */
thr->stack_base = 0;
thr->id = 0;
# ifdef CYGWIN32
thr->pthread_id = 0;
# endif /* CYGWIN32 */
thr->in_use = FALSE;
}
static void GC_delete_thread(DWORD thread_id) {
int i;
LONG my_max = GC_get_max_thread_index();
for (i = 0;
i <= my_max &&
(!thread_table[i].in_use || thread_table[i].id != thread_id);
/* Must still be in_use, since nobody else can store our thread_id. */
i++) {}
if (i > my_max) {
WARN("Removing nonexistent thread %ld\n", (GC_word)thread_id);
} else {
GC_delete_gc_thread(thread_table+i);
}
}
#ifdef CYGWIN32
/* Return a GC_thread corresponding to a given pthread_t. */
/* Returns 0 if it's not there. */
/* We assume that this is only called for pthread ids that */
/* have not yet terminated or are still joinable. */
static GC_thread GC_lookup_thread(pthread_t id)
{
int i;
LONG my_max = GC_get_max_thread_index();
for (i = 0;
i <= my_max &&
(!thread_table[i].in_use || thread_table[i].pthread_id != id
|| !thread_table[i].in_use);
/* Must still be in_use, since nobody else can store our thread_id. */
i++);
if (i > my_max) return 0;
return thread_table + i;
}
#endif /* CYGWIN32 */
void GC_push_thread_structures GC_PROTO((void))
{
/* Unlike the other threads implementations, the thread table here */
/* contains no pointers to the collectable heap. Thus we have */
/* no private structures we need to preserve. */
# ifdef CYGWIN32
{ int i; /* pthreads may keep a pointer in the thread exit value */
LONG my_max = GC_get_max_thread_index();
for (i = 0; i <= my_max; i++)
if (thread_table[i].in_use)
GC_push_all((ptr_t)&(thread_table[i].status),
(ptr_t)(&(thread_table[i].status)+1));
}
# endif
}
/* Defined in misc.c */
extern CRITICAL_SECTION GC_write_cs;
void GC_stop_world()
{
DWORD thread_id = GetCurrentThreadId();
int i;
if (!GC_thr_initialized) ABORT("GC_stop_world() called before GC_thr_init()");
GC_please_stop = TRUE;
# ifndef CYGWIN32
EnterCriticalSection(&GC_write_cs);
# endif /* !CYGWIN32 */
for (i = 0; i <= GC_get_max_thread_index(); i++)
if (thread_table[i].stack_base != 0
&& thread_table[i].id != thread_id) {
# ifdef MSWINCE
/* SuspendThread will fail if thread is running kernel code */
while (SuspendThread(thread_table[i].handle) == (DWORD)-1)
Sleep(10);
# else
/* Apparently the Windows 95 GetOpenFileName call creates */
/* a thread that does not properly get cleaned up, and */
/* SuspendThread on its descriptor may provoke a crash. */
/* This reduces the probability of that event, though it still */
/* appears there's a race here. */
DWORD exitCode;
if (GetExitCodeThread(thread_table[i].handle,&exitCode) &&
exitCode != STILL_ACTIVE) {
thread_table[i].stack_base = 0; /* prevent stack from being pushed */
# ifndef CYGWIN32
/* this breaks pthread_join on Cygwin, which is guaranteed to */
/* only see user pthreads */
thread_table[i].in_use = FALSE;
CloseHandle(thread_table[i].handle);
# endif
continue;
}
if (SuspendThread(thread_table[i].handle) == (DWORD)-1)
ABORT("SuspendThread failed");
# endif
thread_table[i].suspended = TRUE;
}
# ifndef CYGWIN32
LeaveCriticalSection(&GC_write_cs);
# endif /* !CYGWIN32 */
}
void GC_start_world()
{
DWORD thread_id = GetCurrentThreadId();
int i;
LONG my_max = GC_get_max_thread_index();
for (i = 0; i <= my_max; i++)
if (thread_table[i].stack_base != 0 && thread_table[i].suspended
&& thread_table[i].id != thread_id) {
if (ResumeThread(thread_table[i].handle) == (DWORD)-1)
ABORT("ResumeThread failed");
thread_table[i].suspended = FALSE;
}
GC_please_stop = FALSE;
}
# ifdef _MSC_VER
# pragma warning(disable:4715)
# endif
ptr_t GC_current_stackbottom()
{
DWORD thread_id = GetCurrentThreadId();
int i;
LONG my_max = GC_get_max_thread_index();
for (i = 0; i <= my_max; i++)
if (thread_table[i].stack_base && thread_table[i].id == thread_id)
return thread_table[i].stack_base;
ABORT("no thread table entry for current thread");
}
# ifdef _MSC_VER
# pragma warning(default:4715)
# endif
# ifdef MSWINCE
/* The VirtualQuery calls below won't work properly on WinCE, but */
/* since each stack is restricted to an aligned 64K region of */
/* virtual memory we can just take the next lowest multiple of 64K. */
# define GC_get_stack_min(s) \
((ptr_t)(((DWORD)(s) - 1) & 0xFFFF0000))
# else
static ptr_t GC_get_stack_min(ptr_t s)
{
ptr_t bottom;
MEMORY_BASIC_INFORMATION info;
VirtualQuery(s, &info, sizeof(info));
do {
bottom = info.BaseAddress;
VirtualQuery(bottom - 1, &info, sizeof(info));
} while ((info.Protect & PAGE_READWRITE)
&& !(info.Protect & PAGE_GUARD));
return(bottom);
}
# endif
void GC_push_all_stacks()
{
DWORD thread_id = GetCurrentThreadId();
GC_bool found_me = FALSE;
int i;
int dummy;
ptr_t sp, stack_min;
GC_thread thread;
LONG my_max = GC_get_max_thread_index();
for (i = 0; i <= my_max; i++) {
thread = thread_table + i;
if (thread -> in_use && thread -> stack_base) {
if (thread -> id == thread_id) {
sp = (ptr_t) &dummy;
found_me = TRUE;
} else {
CONTEXT context;
context.ContextFlags = CONTEXT_INTEGER|CONTEXT_CONTROL;
if (!GetThreadContext(thread_table[i].handle, &context))
ABORT("GetThreadContext failed");
/* Push all registers that might point into the heap. Frame */
/* pointer registers are included in case client code was */
/* compiled with the 'omit frame pointer' optimisation. */
# define PUSH1(reg) GC_push_one((word)context.reg)
# define PUSH2(r1,r2) PUSH1(r1), PUSH1(r2)
# define PUSH4(r1,r2,r3,r4) PUSH2(r1,r2), PUSH2(r3,r4)
# if defined(__x86_64__)
PUSH4(Rdi,Rsi,Rbx,Rdx), PUSH2(Rcx,Rax), PUSH1(Rbp);
PUSH4(R8,R9,R10,R11), PUSH4(R12,R13,R14,R15);
sp = (ptr_t)context.Rsp;
# elif defined(I386)
PUSH4(Edi,Esi,Ebx,Edx), PUSH2(Ecx,Eax), PUSH1(Ebp);
sp = (ptr_t)context.Esp;
# elif defined(ARM32)
PUSH4(R0,R1,R2,R3),PUSH4(R4,R5,R6,R7),PUSH4(R8,R9,R10,R11),PUSH1(R12);
sp = (ptr_t)context.Sp;
# elif defined(SHx)
PUSH4(R0,R1,R2,R3), PUSH4(R4,R5,R6,R7), PUSH4(R8,R9,R10,R11);
PUSH2(R12,R13), PUSH1(R14);
sp = (ptr_t)context.R15;
# elif defined(MIPS)
PUSH4(IntAt,IntV0,IntV1,IntA0), PUSH4(IntA1,IntA2,IntA3,IntT0);
PUSH4(IntT1,IntT2,IntT3,IntT4), PUSH4(IntT5,IntT6,IntT7,IntS0);
PUSH4(IntS1,IntS2,IntS3,IntS4), PUSH4(IntS5,IntS6,IntS7,IntT8);
PUSH4(IntT9,IntK0,IntK1,IntS8);
sp = (ptr_t)context.IntSp;
# elif defined(PPC)
PUSH4(Gpr0, Gpr3, Gpr4, Gpr5), PUSH4(Gpr6, Gpr7, Gpr8, Gpr9);
PUSH4(Gpr10,Gpr11,Gpr12,Gpr14), PUSH4(Gpr15,Gpr16,Gpr17,Gpr18);
PUSH4(Gpr19,Gpr20,Gpr21,Gpr22), PUSH4(Gpr23,Gpr24,Gpr25,Gpr26);
PUSH4(Gpr27,Gpr28,Gpr29,Gpr30), PUSH1(Gpr31);
sp = (ptr_t)context.Gpr1;
# elif defined(ALPHA)
PUSH4(IntV0,IntT0,IntT1,IntT2), PUSH4(IntT3,IntT4,IntT5,IntT6);
PUSH4(IntT7,IntS0,IntS1,IntS2), PUSH4(IntS3,IntS4,IntS5,IntFp);
PUSH4(IntA0,IntA1,IntA2,IntA3), PUSH4(IntA4,IntA5,IntT8,IntT9);
PUSH4(IntT10,IntT11,IntT12,IntAt);
sp = (ptr_t)context.IntSp;
# else
# error "architecture is not supported"
# endif
}
stack_min = GC_get_stack_min(thread->stack_base);
if (sp >= stack_min && sp < thread->stack_base)
GC_push_all_stack(sp, thread->stack_base);
else {
WARN("Thread stack pointer 0x%lx out of range, pushing everything\n",
(unsigned long)sp);
GC_push_all_stack(stack_min, thread->stack_base);
}
}
}
if (!found_me) ABORT("Collecting from unknown thread.");
}
void GC_get_next_stack(char *start, char **lo, char **hi)
{
int i;
# define ADDR_LIMIT (char *)(-1L)
char * current_min = ADDR_LIMIT;
LONG my_max = GC_get_max_thread_index();
for (i = 0; i <= my_max; i++) {
char * s = (char *)thread_table[i].stack_base;
if (0 != s && s > start && s < current_min) {
current_min = s;
}
}
*hi = current_min;
if (current_min == ADDR_LIMIT) {
*lo = ADDR_LIMIT;
return;
}
*lo = GC_get_stack_min(current_min);
if (*lo < start) *lo = start;
}
#if !defined(CYGWIN32)
#if !defined(MSWINCE) && defined(GC_DLL)
/* We register threads from DllMain */
GC_API HANDLE WINAPI GC_CreateThread(
LPSECURITY_ATTRIBUTES lpThreadAttributes,
DWORD dwStackSize, LPTHREAD_START_ROUTINE lpStartAddress,
LPVOID lpParameter, DWORD dwCreationFlags, LPDWORD lpThreadId )
{
return CreateThread(lpThreadAttributes, dwStackSize, lpStartAddress,
lpParameter, dwCreationFlags, lpThreadId);
}
#else /* defined(MSWINCE) || !defined(GC_DLL)) */
/* We have no DllMain to take care of new threads. Thus we */
/* must properly intercept thread creation. */
typedef struct {
LPTHREAD_START_ROUTINE start;
LPVOID param;
} thread_args;
static DWORD WINAPI thread_start(LPVOID arg);
GC_API HANDLE WINAPI GC_CreateThread(
LPSECURITY_ATTRIBUTES lpThreadAttributes,
DWORD dwStackSize, LPTHREAD_START_ROUTINE lpStartAddress,
LPVOID lpParameter, DWORD dwCreationFlags, LPDWORD lpThreadId )
{
HANDLE thread_h = NULL;
thread_args *args;
if (!GC_is_initialized) GC_init();
/* make sure GC is initialized (i.e. main thread is attached) */
args = GC_malloc_uncollectable(sizeof(thread_args));
/* Handed off to and deallocated by child thread. */
if (0 == args) {
SetLastError(ERROR_NOT_ENOUGH_MEMORY);
return NULL;
}
/* set up thread arguments */
args -> start = lpStartAddress;
args -> param = lpParameter;
thread_h = CreateThread(lpThreadAttributes,
dwStackSize, thread_start,
args, dwCreationFlags,
lpThreadId);
return thread_h;
}
static DWORD WINAPI thread_start(LPVOID arg)
{
DWORD ret = 0;
thread_args *args = (thread_args *)arg;
GC_new_thread();
/* Clear the thread entry even if we exit with an exception. */
/* This is probably pointless, since an uncaught exception is */
/* supposed to result in the process being killed. */
#ifndef __GNUC__
__try {
#endif /* __GNUC__ */
ret = args->start (args->param);
#ifndef __GNUC__
} __finally {
#endif /* __GNUC__ */
GC_free(args);
GC_delete_thread(GetCurrentThreadId());
#ifndef __GNUC__
}
#endif /* __GNUC__ */
return ret;
}
#endif /* !defined(MSWINCE) && !(defined(__MINGW32__) && !defined(_DLL)) */
#endif /* !CYGWIN32 */
#ifdef MSWINCE
typedef struct {
HINSTANCE hInstance;
HINSTANCE hPrevInstance;
LPWSTR lpCmdLine;
int nShowCmd;
} main_thread_args;
DWORD WINAPI main_thread_start(LPVOID arg);
int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,
LPWSTR lpCmdLine, int nShowCmd)
{
DWORD exit_code = 1;
main_thread_args args = {
hInstance, hPrevInstance, lpCmdLine, nShowCmd
};
HANDLE thread_h;
DWORD thread_id;
/* initialize everything */
GC_init();
/* start the main thread */
thread_h = GC_CreateThread(
NULL, 0, main_thread_start, &args, 0, &thread_id);
if (thread_h != NULL)
{
WaitForSingleObject (thread_h, INFINITE);
GetExitCodeThread (thread_h, &exit_code);
CloseHandle (thread_h);
}
GC_deinit();
DeleteCriticalSection(&GC_allocate_ml);
return (int) exit_code;
}
DWORD WINAPI main_thread_start(LPVOID arg)
{
main_thread_args * args = (main_thread_args *) arg;
return (DWORD) GC_WinMain (args->hInstance, args->hPrevInstance,
args->lpCmdLine, args->nShowCmd);
}
# else /* !MSWINCE */
/* Called by GC_init() - we hold the allocation lock. */
void GC_thr_init() {
if (GC_thr_initialized) return;
GC_main_thread = GetCurrentThreadId();
GC_thr_initialized = TRUE;
/* Add the initial thread, so we can stop it. */
GC_new_thread();
}
#ifdef CYGWIN32
struct start_info {
void *(*start_routine)(void *);
void *arg;
GC_bool detached;
};
int GC_pthread_join(pthread_t pthread_id, void **retval) {
int result;
int i;
GC_thread me;
# if DEBUG_CYGWIN_THREADS
GC_printf3("thread 0x%x(0x%x) is joining thread 0x%x.\n",
(int)pthread_self(), GetCurrentThreadId(), (int)pthread_id);
# endif
/* Thread being joined might not have registered itself yet. */
/* After the join,thread id may have been recycled. */
/* FIXME: It would be better if this worked more like */
/* pthread_support.c. */
while ((me = GC_lookup_thread(pthread_id)) == 0) Sleep(10);
result = pthread_join(pthread_id, retval);
GC_delete_gc_thread(me);
# if DEBUG_CYGWIN_THREADS
GC_printf3("thread 0x%x(0x%x) completed join with thread 0x%x.\n",
(int)pthread_self(), GetCurrentThreadId(), (int)pthread_id);
# endif
return result;
}
/* Cygwin-pthreads calls CreateThread internally, but it's not
* easily interceptible by us..
* so intercept pthread_create instead
*/
int
GC_pthread_create(pthread_t *new_thread,
const pthread_attr_t *attr,
void *(*start_routine)(void *), void *arg) {
int result;
struct start_info * si;
if (!GC_is_initialized) GC_init();
/* make sure GC is initialized (i.e. main thread is attached) */
/* This is otherwise saved only in an area mmapped by the thread */
/* library, which isn't visible to the collector. */
si = GC_malloc_uncollectable(sizeof(struct start_info));
if (0 == si) return(EAGAIN);
si -> start_routine = start_routine;
si -> arg = arg;
if (attr != 0 &&
pthread_attr_getdetachstate(attr, &si->detached)
== PTHREAD_CREATE_DETACHED) {
si->detached = TRUE;
}
# if DEBUG_CYGWIN_THREADS
GC_printf2("About to create a thread from 0x%x(0x%x)\n",
(int)pthread_self(), GetCurrentThreadId);
# endif
result = pthread_create(new_thread, attr, GC_start_routine, si);
if (result) { /* failure */
GC_free(si);
}
return(result);
}
void * GC_start_routine(void * arg)
{
struct start_info * si = arg;
void * result;
void *(*start)(void *);
void *start_arg;
pthread_t pthread_id;
GC_thread me;
GC_bool detached;
int i;
# if DEBUG_CYGWIN_THREADS
GC_printf2("thread 0x%x(0x%x) starting...\n",(int)pthread_self(),
GetCurrentThreadId());
# endif
/* If a GC occurs before the thread is registered, that GC will */
/* ignore this thread. That's fine, since it will block trying to */
/* acquire the allocation lock, and won't yet hold interesting */
/* pointers. */
LOCK();
/* We register the thread here instead of in the parent, so that */
/* we don't need to hold the allocation lock during pthread_create. */
me = GC_new_thread();
UNLOCK();
start = si -> start_routine;
start_arg = si -> arg;
if (si-> detached) me -> flags |= DETACHED;
me -> pthread_id = pthread_id = pthread_self();
GC_free(si); /* was allocated uncollectable */
pthread_cleanup_push(GC_thread_exit_proc, (void *)me);
result = (*start)(start_arg);
me -> status = result;
pthread_cleanup_pop(0);
# if DEBUG_CYGWIN_THREADS
GC_printf2("thread 0x%x(0x%x) returned from start routine.\n",
(int)pthread_self(),GetCurrentThreadId());
# endif
return(result);
}
void GC_thread_exit_proc(void *arg)
{
GC_thread me = (GC_thread)arg;
int i;
# if DEBUG_CYGWIN_THREADS
GC_printf2("thread 0x%x(0x%x) called pthread_exit().\n",
(int)pthread_self(),GetCurrentThreadId());
# endif
LOCK();
if (me -> flags & DETACHED) {
GC_delete_thread(GetCurrentThreadId());
} else {
/* deallocate it as part of join */
me -> flags |= FINISHED;
}
UNLOCK();
}
/* nothing required here... */
int GC_pthread_sigmask(int how, const sigset_t *set, sigset_t *oset) {
return pthread_sigmask(how, set, oset);
}
int GC_pthread_detach(pthread_t thread)
{
int result;
GC_thread thread_gc_id;
LOCK();
thread_gc_id = GC_lookup_thread(thread);
UNLOCK();
result = pthread_detach(thread);
if (result == 0) {
LOCK();
thread_gc_id -> flags |= DETACHED;
/* Here the pthread thread id may have been recycled. */
if (thread_gc_id -> flags & FINISHED) {
GC_delete_gc_thread(thread_gc_id);
}
UNLOCK();
}
return result;
}
GC_PTR GC_get_thread_stack_base()
{
#ifdef __x86_64__
return ((NT_TIB*)NtCurrentTeb())->StackBase;
#else
extern GC_PTR _tlsbase __asm__ ("%fs:4");
return _tlsbase;
#endif
}
#else /* !CYGWIN32 */
/*
* We avoid acquiring locks here, since this doesn't seem to be preemptable.
* Pontus Rydin suggests wrapping the thread start routine instead.
*/
#ifdef GC_DLL
BOOL WINAPI DllMain(HINSTANCE inst, ULONG reason, LPVOID reserved)
{
switch (reason) {
case DLL_PROCESS_ATTACH:
GC_init(); /* Force initialization before thread attach. */
/* fall through */
case DLL_THREAD_ATTACH:
GC_ASSERT(GC_thr_initialized);
if (GC_main_thread != GetCurrentThreadId()) {
GC_new_thread();
} /* o.w. we already did it during GC_thr_init(), called by GC_init() */
break;
case DLL_THREAD_DETACH:
GC_delete_thread(GetCurrentThreadId());
break;
case DLL_PROCESS_DETACH:
{
int i;
LOCK();
for (i = 0; i <= GC_get_max_thread_index(); ++i)
{
if (thread_table[i].in_use)
GC_delete_gc_thread(thread_table + i);
}
UNLOCK();
GC_deinit();
DeleteCriticalSection(&GC_allocate_ml);
}
break;
}
return TRUE;
}
#endif /* GC_DLL */
#endif /* !CYGWIN32 */
# endif /* !MSWINCE */
#endif /* GC_WIN32_THREADS */