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-rw-r--r--libpthread/nptl/unwind.c176
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diff --git a/libpthread/nptl/unwind.c b/libpthread/nptl/unwind.c
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+/* Copyright (C) 2003, 2004 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, adj) \
+ ((uintptr_t) frame - adj >= (uintptr_t) other - adj)
+#elif _STACK_GROWS_UP
+# define FRAME_LEFT(frame, other, adj) \
+ ((uintptr_t) frame - adj <= (uintptr_t) other - adj)
+#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;
+
+ /* Adjust all pointers used in comparisons, so that top of thread's
+ stack is at the top of address space. Without that, things break
+ if stack is allocated above the main stack. */
+ uintptr_t adj = (uintptr_t) self->stackblock + self->stackblock_size;
+
+ /* 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_ADJ (buf->cancel_jmp_buf[0].jmp_buf, context,
+ adj))
+ 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, adj)))
+ {
+ 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, adj)));
+
+ /* Mark the current element as handled. */
+ THREAD_SETMEM (self, cleanup, curp);
+ }
+ }
+
+ if (do_longjump)
+ __libc_unwind_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_unwind_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)