newlib/winsup/cygwin/init.cc

112 lines
2.8 KiB
C++

/* init.cc
Copyright 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004 Red Hat, Inc.
This file is part of Cygwin.
This software is a copyrighted work licensed under the terms of the
Cygwin license. Please consult the file "CYGWIN_LICENSE" for
details. */
#include "winsup.h"
#include <stdlib.h>
#include "thread.h"
#include "perprocess.h"
#include "cygthread.h"
#include "cygtls.h"
int NO_COPY dynamically_loaded;
static char *search_for = (char *) cygthread::stub;
static unsigned threadfunc_ix __attribute__((section ("cygwin_dll_common"), shared)) = 0;
DWORD tls_func;
HANDLE sync_startup;
#define OLDFUNC_OFFSET -1
static void WINAPI
threadfunc_fe (VOID *arg)
{
_threadinfo::call ((DWORD (*) (void *, void *)) (((char **) _tlsbase)[OLDFUNC_OFFSET]), arg);
// void *threadfunc = (void *) TlsGetValue (tls_func);
// TlsFree (tls_func);
// _threadinfo::call ((DWORD (*) (void *, void *)) (threadfunc), arg);
}
static DWORD WINAPI
calibration_thread (VOID *arg)
{
ExitThread (0);
}
static void
munge_threadfunc (HANDLE cygwin_hmodule)
{
char **ebp = (char **) __builtin_frame_address (0);
if (!threadfunc_ix)
{
for (char **peb = ebp; peb < (char **) _tlsbase; peb++)
if (*peb == search_for)
{
threadfunc_ix = peb - ebp;
goto foundit;
}
#ifdef DEBUGGING
system_printf ("non-fatal warning: unknown thread! search_for %p, cygthread::stub %p, calibration_thread %p, possible func offset %p",
search_for, cygthread::stub, calibration_thread, ebp[137]);
#endif
try_to_debug ();
return;
}
foundit:
char *threadfunc = ebp[threadfunc_ix];
if (threadfunc == (char *) calibration_thread)
/* no need for the overhead */;
else
{
ebp[threadfunc_ix] = (char *) threadfunc_fe;
((char **) _tlsbase)[OLDFUNC_OFFSET] = threadfunc;
// TlsSetValue (tls_func, (void *) threadfunc);
}
}
void
prime_threads ()
{
// tls_func = TlsAlloc ();
if (!threadfunc_ix)
{
DWORD id;
search_for = (char *) calibration_thread;
sync_startup = CreateThread (NULL, 0, calibration_thread, 0, 0, &id);
}
}
extern void __stdcall dll_crt0_0 ();
extern "C" int WINAPI
dll_entry (HANDLE h, DWORD reason, void *static_load)
{
switch (reason)
{
case DLL_PROCESS_ATTACH:
prime_threads ();
dynamically_loaded = (static_load == NULL);
// __cygwin_user_data.impure_ptr = &_my_tls.local_clib;
dll_crt0_0 ();
// small_printf ("%u, %p, %p\n", cygwin_pid (GetCurrentProcessId ()), _tlstop, _tlsbase);
break;
case DLL_PROCESS_DETACH:
break;
case DLL_THREAD_ATTACH:
munge_threadfunc (h);
// small_printf ("%u, %p, %p\n", cygwin_pid (GetCurrentProcessId ()), _tlstop, _tlsbase);
break;
case DLL_THREAD_DETACH:
_my_tls.remove (0);
break;
}
return 1;
}