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/* Copyright (C) 2003 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@redhat.com>
and Richard Henderson <rth@redhat.com>, 2003.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include <setjmp.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "pthreadP.h"
#include "jmpbuf-unwind.h"
#ifdef HAVE_FORCED_UNWIND
#ifdef _STACK_GROWS_DOWN
# define FRAME_LEFT(frame, other) ((char *) frame >= (char *) other)
#elif _STACK_GROWS_UP
# define FRAME_LEFT(frame, other) ((char *) frame <= (char *) other)
#else
# error "Define either _STACK_GROWS_DOWN or _STACK_GROWS_UP"
#endif
static _Unwind_Reason_Code
unwind_stop (int version, _Unwind_Action actions,
_Unwind_Exception_Class exc_class,
struct _Unwind_Exception *exc_obj,
struct _Unwind_Context *context, void *stop_parameter)
{
struct pthread_unwind_buf *buf = stop_parameter;
struct pthread *self = THREAD_SELF;
struct _pthread_cleanup_buffer *curp = THREAD_GETMEM (self, cleanup);
int do_longjump = 0;
/* Do longjmp if we're at "end of stack", aka "end of unwind data".
We assume there are only C frame without unwind data in between
here and the jmp_buf target. Otherwise simply note that the CFA
of a function is NOT within it's stack frame; it's the SP of the
previous frame. */
if ((actions & _UA_END_OF_STACK)
|| ! _JMPBUF_CFA_UNWINDS (buf->cancel_jmp_buf[0].jmp_buf, context))
do_longjump = 1;
if (__builtin_expect (curp != NULL, 0))
{
/* Handle the compatibility stuff. Execute all handlers
registered with the old method which would be unwound by this
step. */
struct _pthread_cleanup_buffer *oldp = buf->priv.data.cleanup;
void *cfa = (void *) _Unwind_GetCFA (context);
if (curp != oldp && (do_longjump || FRAME_LEFT (cfa, curp)))
{
do
{
/* Pointer to the next element. */
struct _pthread_cleanup_buffer *nextp = curp->__prev;
/* Call the handler. */
curp->__routine (curp->__arg);
/* To the next. */
curp = nextp;
}
while (curp != oldp && (do_longjump || FRAME_LEFT (cfa, curp)));
/* Mark the current element as handled. */
THREAD_SETMEM (self, cleanup, curp);
}
}
if (do_longjump)
__libc_longjmp ((struct __jmp_buf_tag *) buf->cancel_jmp_buf, 1);
return _URC_NO_REASON;
}
static void
unwind_cleanup (_Unwind_Reason_Code reason, struct _Unwind_Exception *exc)
{
/* When we get here a C++ catch block didn't rethrow the object. We
cannot handle this case and therefore abort. */
# define STR_N_LEN(str) str, strlen (str)
INTERNAL_SYSCALL_DECL (err);
INTERNAL_SYSCALL (write, err, 3, STDERR_FILENO,
STR_N_LEN ("FATAL: exception not rethrown\n"));
abort ();
}
#endif /* have forced unwind */
void
__cleanup_fct_attribute __attribute ((noreturn))
__pthread_unwind (__pthread_unwind_buf_t *buf)
{
struct pthread_unwind_buf *ibuf = (struct pthread_unwind_buf *) buf;
struct pthread *self = THREAD_SELF;
#ifdef HAVE_FORCED_UNWIND
/* This is not a catchable exception, so don't provide any details about
the exception type. We do need to initialize the field though. */
THREAD_SETMEM (self, exc.exception_class, 0);
THREAD_SETMEM (self, exc.exception_cleanup, unwind_cleanup);
_Unwind_ForcedUnwind (&self->exc, unwind_stop, ibuf);
#else
/* Handle the compatibility stuff first. Execute all handlers
registered with the old method. We don't execute them in order,
instead, they will run first. */
struct _pthread_cleanup_buffer *oldp = ibuf->priv.data.cleanup;
struct _pthread_cleanup_buffer *curp = THREAD_GETMEM (self, cleanup);
if (curp != oldp)
{
do
{
/* Pointer to the next element. */
struct _pthread_cleanup_buffer *nextp = curp->__prev;
/* Call the handler. */
curp->__routine (curp->__arg);
/* To the next. */
curp = nextp;
}
while (curp != oldp);
/* Mark the current element as handled. */
THREAD_SETMEM (self, cleanup, curp);
}
/* We simply jump to the registered setjmp buffer. */
__libc_longjmp ((struct __jmp_buf_tag *) ibuf->cancel_jmp_buf, 1);
#endif
/* NOTREACHED */
/* We better do not get here. */
abort ();
}
hidden_def (__pthread_unwind)
void
__cleanup_fct_attribute __attribute ((noreturn))
__pthread_unwind_next (__pthread_unwind_buf_t *buf)
{
struct pthread_unwind_buf *ibuf = (struct pthread_unwind_buf *) buf;
__pthread_unwind ((__pthread_unwind_buf_t *) ibuf->priv.data.prev);
}
hidden_def (__pthread_unwind_next)
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