sysdeps/gnu/unwind-resume.c

   1 /* Copyright (C) 2003-2018 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Jakub Jelinek <jakub@redhat.com>.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public License as
   7    published by the Free Software Foundation; either version 2.1 of the
   8    License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; see the file COPYING.LIB.  If
  17    not, see <http://www.gnu.org/licenses/>.  */
  18
  19 #include <dlfcn.h>
  20 #include <stdio.h>
  21 #include <unwind.h>
  22 #include <gnu/lib-names.h>
  23 #include <sysdep.h>
  24 #include <unwind-resume.h>
  25
  26
  27 void (*__libgcc_s_resume) (struct _Unwind_Exception *exc)
  28   attribute_hidden __attribute__ ((noreturn));
  29
  30 static _Unwind_Reason_Code (*libgcc_s_personality) PERSONALITY_PROTO;
  31
  32 void attribute_hidden __attribute__ ((cold))
  33 __libgcc_s_init (void)
  34 {
  35   void *resume, *personality;
  36   void *handle;
  37
  38   /* See include/dlfcn.h. Use of __libc_dlopen requires RTLD_NOW.  */
  39   handle = __libc_dlopen (LIBGCC_S_SO);
  40
  41   if (handle == NULL
  42       || (resume = __libc_dlsym (handle, "_Unwind_Resume")) == NULL
  43       || (personality = __libc_dlsym (handle, "__gcc_personality_v0")) == NULL)
  44     __libc_fatal (LIBGCC_S_SO
  45                   " must be installed for unwinding to work\n");
  46
  47 #ifdef PTR_MANGLE
  48   PTR_MANGLE (resume);
  49 #endif
  50   __libgcc_s_resume = resume;
  51 #ifdef PTR_MANGLE
  52   PTR_MANGLE (personality);
  53 #endif
  54   libgcc_s_personality = personality;
  55 }
  56
  57 #if !HAVE_ARCH_UNWIND_RESUME
  58 void
  59 _Unwind_Resume (struct _Unwind_Exception *exc)
  60 {
  61   if (__glibc_unlikely (__libgcc_s_resume == NULL))
  62     __libgcc_s_init ();
  63
  64   __typeof (__libgcc_s_resume) resume = __libgcc_s_resume;
  65 #ifdef PTR_DEMANGLE
  66   PTR_DEMANGLE (resume);
  67 #endif
  68   (*resume) (exc);
  69 }
  70 #endif
  71
  72 _Unwind_Reason_Code
  73 __gcc_personality_v0 PERSONALITY_PROTO
  74 {
  75   if (__glibc_unlikely (libgcc_s_personality == NULL))
  76     __libgcc_s_init ();
  77
  78   __typeof (libgcc_s_personality) personality = libgcc_s_personality;
  79 #ifdef PTR_DEMANGLE
  80   PTR_DEMANGLE (personality);
  81 #endif
  82   return (*personality) PERSONALITY_ARGS;
  83 }