2008-03-01 Christopher Faylor <me+cygwin@cgf.cx>

	* cygtls.h (_cygtls::handle_threadlist_exception): Eliminate.
	(_cygtls::init_threadlist_exceptions): Ditto.
	* cygtls.cc (_cygtls::handle_threadlist_exception): Eliminate.
	(_cygtls::init_threadlist_exceptions): Ditto.
	(_cygtls::find_tls): Use myfault handling to deal with errors caused by
	nonexistent threads.
	* sigproc.cc (wait_sig): Eliminate call to init_threadlist_exceptions.

2008-03-01  Christopher Faylor  <me+cygwin@cgf.cx>

	* cygtls.cc (_cygtls::init_exception_handler): Just return.

2008-03-01  Corinna Vinschen  <corinna@vinschen.de>

	* exceptions.cc (_cygtls::handle_exceptions): Only call rtl_unwind when
	exiting.  Just return, don't set thread context.
	* gendef (_setjmp): Store %fs:0 in jmp_buf.
	(_sjfault): Ditto.
	(_ljfault): Restore %fs:0 from jmp_buf.
	(_longjmp): Ditto.

6 files changed, 45 insertions, 62 deletions

diff --git a/winsup/cygwin/ChangeLog b/winsup/cygwin/ChangeLog
index ef73223..b02bab1 100644
--- a/winsup/cygwin/ChangeLog
+++ b/winsup/cygwin/ChangeLog
@@ -1,3 +1,26 @@
+2008-03-01  Christopher Faylor  <me+cygwin@cgf.cx>
+
+	* cygtls.h (_cygtls::handle_threadlist_exception): Eliminate.
+	(_cygtls::init_threadlist_exceptions): Ditto.
+	* cygtls.cc (_cygtls::handle_threadlist_exception): Eliminate.
+	(_cygtls::init_threadlist_exceptions): Ditto.
+	(_cygtls::find_tls): Use myfault handling to deal with errors caused by
+	nonexistent threads.
+	* sigproc.cc (wait_sig): Eliminate call to init_threadlist_exceptions.
+
+2008-03-01  Christopher Faylor  <me+cygwin@cgf.cx>
+
+	* cygtls.cc (_cygtls::init_exception_handler): Just return.
+
+2008-03-01  Corinna Vinschen  <corinna@vinschen.de>
+
+	* exceptions.cc (_cygtls::handle_exceptions): Only call rtl_unwind when
+	exiting.  Just return, don't set thread context.
+	* gendef (_setjmp): Store %fs:0 in jmp_buf.
+	(_sjfault): Ditto.
+	(_ljfault): Restore %fs:0 from jmp_buf.
+	(_longjmp): Ditto.
+
 2008-02-29  Corinna Vinschen  <corinna@vinschen.de>
 
 	* fhandler_disk_file.cc (fhandler_disk_file::fchmod): Call close_fs
diff --git a/winsup/cygwin/cygtls.cc b/winsup/cygwin/cygtls.cc
index c2d7c2e..88fd497 100644
--- a/winsup/cygwin/cygtls.cc
+++ b/winsup/cygwin/cygtls.cc
@@ -196,23 +196,28 @@ _cygtls::push (__stack_t addr)
   *stackptr++ = (__stack_t) addr;
 }
 
-#define BAD_IX ((size_t) -1)
-static size_t NO_COPY threadlist_ix = BAD_IX;
 
 _cygtls *
 _cygtls::find_tls (int sig)
 {
+  static int NO_COPY threadlist_ix;
+
   debug_printf ("sig %d\n", sig);
   sentry here (INFINITE);
-  __asm__ volatile (".equ _threadlist_exception_return,.");
+
   _cygtls *res = NULL;
-  for (threadlist_ix = 0; threadlist_ix < nthreads; threadlist_ix++)
+  threadlist_ix = -1;
+
+  myfault efault;
+  if (efault.faulted ())
+    cygheap->threadlist[threadlist_ix]->remove (INFINITE);
+
+  while (++threadlist_ix < (int) nthreads)
     if (sigismember (&(cygheap->threadlist[threadlist_ix]->sigwait_mask), sig))
       {
 	res = cygheap->threadlist[threadlist_ix];
 	break;
       }
-  threadlist_ix = BAD_IX;
   return res;
 }
 
@@ -222,36 +227,6 @@ _cygtls::set_siginfo (sigpacket *pack)
   infodata = pack->si;
 }
 
-extern "C" DWORD __stdcall RtlUnwind (void *, void *, void *, DWORD) __attribute__ ((noreturn));
-int
-_cygtls::handle_threadlist_exception (EXCEPTION_RECORD *e, exception_list *frame, CONTEXT *c, void *)
-{
-  if (e->ExceptionCode != STATUS_ACCESS_VIOLATION)
-    {
-      system_printf ("unhandled exception %p at %p", e->ExceptionCode, c->Eip);
-      return 1;
-    }
-
-  sentry here;
-  if (threadlist_ix == BAD_IX)
-    {
-      api_fatal ("called with threadlist_ix %d", BAD_IX);
-      return 1;
-    }
-
-  if (!here.acquired ())
-    {
-      system_printf ("couldn't aquire muto");
-      return 1;
-    }
-
-  extern void *threadlist_exception_return;
-  cygheap->threadlist[threadlist_ix]->remove (INFINITE);
-  threadlist_ix = 0;
-  RtlUnwind (frame, threadlist_exception_return, e, 0);
-  /* Never returns */
-}
-
 /* Set up the exception handler for the current thread.  The x86 uses segment
    register fs, offset 0 to point to the current exception handler. */
 
@@ -275,9 +250,3 @@ _cygtls::init_exception_handler (exception_handler *eh)
   el.prev = _except_list;
   _except_list = &el;
 }
-
-void
-_cygtls::init_threadlist_exceptions ()
-{
-  init_exception_handler (handle_threadlist_exception);
-}
diff --git a/winsup/cygwin/cygtls.h b/winsup/cygwin/cygtls.h
index 97800a7..e60eb35 100644
--- a/winsup/cygwin/cygtls.h
+++ b/winsup/cygwin/cygtls.h
@@ -195,9 +195,7 @@ struct _cygtls
 
   /* exception handling */
   static int handle_exceptions (EXCEPTION_RECORD *, exception_list *, CONTEXT *, void *);
-  static int handle_threadlist_exception (EXCEPTION_RECORD *e, exception_list *frame, CONTEXT *c, void *);
   void init_exception_handler (int (*) (EXCEPTION_RECORD *, exception_list *, CONTEXT *, void*));
-  void init_threadlist_exceptions ();
   void signal_exit (int) __attribute__ ((noreturn, regparm(2)));
   void copy_context (CONTEXT *) __attribute__ ((regparm(2)));
   void signal_debugger (int) __attribute__ ((regparm(2)));
diff --git a/winsup/cygwin/exceptions.cc b/winsup/cygwin/exceptions.cc
index 9dfe6f3..ce98d21 100644
--- a/winsup/cygwin/exceptions.cc
+++ b/winsup/cygwin/exceptions.cc
@@ -583,8 +583,6 @@ _cygtls::handle_exceptions (EXCEPTION_RECORD *e, exception_list *frame, CONTEXT
       return 1;
     }
 
-  rtl_unwind (frame, e);
-
   debug_printf ("In cygwin_except_handler exc %p at %p sp %p", e->ExceptionCode, in->Eip, in->Esp);
   debug_printf ("In cygwin_except_handler sig %d at %p", si.si_signo, in->Eip);
 
@@ -634,6 +632,7 @@ _cygtls::handle_exceptions (EXCEPTION_RECORD *e, exception_list *frame, CONTEXT
 	      goto out;
 	    }
 
+	  rtl_unwind (frame, e);
 	  open_stackdumpfile ();
 	  exception (e, in);
 	  stackdump ((DWORD) ebp, 0, 1);
@@ -664,21 +663,8 @@ _cygtls::handle_exceptions (EXCEPTION_RECORD *e, exception_list *frame, CONTEXT
   sig_send (NULL, si, &me);	// Signal myself
   me.incyg--;
   e->ExceptionFlags = 0;
-  /* The OS adds an exception list frame to the stack.  It expects to be
-     able to remove this entry after the exception handler returned.
-     However, when unwinding to our frame, our frame becomes the uppermost
-     frame on the stack (%fs:0 points to frame).  This way, our frame
-     is removed from the exception stack and just disappears.  So, we can't
-     just return here or things will be screwed up by the helpful function
-     in (presumably) ntdll.dll.
-
-     So, instead, we will do the equivalent of a longjmp here and return
-     to the caller without visiting any of the helpful code installed prior
-     to this function.  This should work ok, since a longjmp() out of here has
-     to work if linux signal semantics are to be maintained. */
 out:
-  SetThreadContext (GetCurrentThread (), in);
-  return 0; /* Never actually returns.  This is just to keep gcc happy. */
+  return 0;
 }
 
 /* Utilities to call a user supplied exception handler.  */
diff --git a/winsup/cygwin/gendef b/winsup/cygwin/gendef
index 0d7df4b..28d4b31 100755
--- a/winsup/cygwin/gendef
+++ b/winsup/cygwin/gendef
@@ -332,12 +332,14 @@ _setjmp:
 	movw	%ax,40(%edi)
 	movw	%ss,%ax
 	movw	%ax,42(%edi)
+	movl	%fs:0,%eax
+	movl	%eax,44(%edi)
 	pushl	%ebx
 	call	stabilize_sig_stack
 	movl	$tls::stackptr(%ebx),%eax		# save stack pointer contents
 	decl	$tls::stacklock(%ebx)
 	popl	%ebx
-	movl	%eax,44(%edi)
+	movl	%eax,48(%edi)
 	popl	%edi
 	movl	\$0,%eax
 	leave
@@ -371,6 +373,8 @@ ___sjfault:
 	movw	%ax,40(%edi)
 	movw	%ss,%ax
 	movw	%ax,42(%edi)
+	movl	%fs:0,%eax
+	movl	%eax,44(%edi)
 	popl	%edi
 	movl	\$0,%eax
 	leave
@@ -391,6 +395,8 @@ ___ljfault:
 	movl	24(%edi),%ebp
 	pushfl
 	popl	%ebx
+	movl	44(%edi),%eax
+	movl	%eax,%fs:0
 	movw	42(%edi),%ax
 	movw	%ax,%ss
 	movl	28(%edi),%esp
@@ -415,7 +421,7 @@ _longjmp:
 	movl	%esp,%ebp
 	movl	8(%ebp),%edi				# address of buffer
 	call	stabilize_sig_stack
-	movl	44(%edi),%eax				# get old signal stack
+	movl	48(%edi),%eax				# get old signal stack
 	movl	%eax,$tls::stackptr(%ebx)		# restore
 	decl	$tls::stacklock(%ebx)			# relinquish lock
 	xorl	%eax,%eax
@@ -430,6 +436,8 @@ _longjmp:
 	movl	24(%edi),%ebp
 	pushfl
 	popl	%ebx
+	movl	44(%edi),%eax
+	movl	%eax,%fs:0
 	movw	42(%edi),%ax
 	movw	%ax,%ss
 	movl	28(%edi),%esp
diff --git a/winsup/cygwin/sigproc.cc b/winsup/cygwin/sigproc.cc
index 863f9e1..bcf331e 100644
--- a/winsup/cygwin/sigproc.cc
+++ b/winsup/cygwin/sigproc.cc
@@ -1166,7 +1166,6 @@ wait_sig (VOID *)
   SetEvent (wait_sig_inited);
 
   _sig_tls = &_my_tls;
-  _sig_tls->init_threadlist_exceptions ();
   sigproc_printf ("entering ReadFile loop, my_readsig %p, my_sendsig %p",
 		  my_readsig, my_sendsig);