1
2/*--------------------------------------------------------------------*/
3/*--- Notional "implementation" for m_vki.                         ---*/
4/*---                                                      m_vki.c ---*/
5/*--------------------------------------------------------------------*/
6
7/*
8   This file is part of Valgrind, a dynamic binary instrumentation
9   framework.
10
11   Copyright (C) 2006-2011 OpenWorks LLP
12      info@open-works.co.uk
13
14   This program is free software; you can redistribute it and/or
15   modify it under the terms of the GNU General Public License as
16   published by the Free Software Foundation; either version 2 of the
17   License, or (at your option) any later version.
18
19   This program is distributed in the hope that it will be useful, but
20   WITHOUT ANY WARRANTY; without even the implied warranty of
21   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
22   General Public License for more details.
23
24   You should have received a copy of the GNU General Public License
25   along with this program; if not, write to the Free Software
26   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
27   02111-1307, USA.
28
29   The GNU General Public License is contained in the file COPYING.
30*/
31
32#include "pub_core_basics.h"
33#include "pub_core_libcassert.h"
34#include "pub_core_vki.h"     /* self */
35
36/* We have pub_{core,tool}_vki.h.  This is the matching implementation
37   for that interface.  In fact there is no implementation, as the
38   sole purpose of the module is to export types and constants
39   describing the kernel interface, so this file is nearly empty. */
40
41
42/* ppc32/64-linux determines page size at startup, hence m_vki is
43   the logical place to store that info. */
44
45#if defined(VGP_ppc32_linux) || defined(VGP_ppc64_linux)
46unsigned long VKI_PAGE_SHIFT = 12;
47unsigned long VKI_PAGE_SIZE  = 1UL << 12;
48#endif
49
50
51/* Do initial consistency checks on some of the definitions to do with
52   signals (vki_sigset_t and vki_sigaction_{toK,fromK}_t).  This stuff
53   is fragile enough that it's important to check at startup that
54   the world looks like what we expect it to look like.
55
56   The most important thing is to check that the definition of signal
57   sets for this platform is right.  A signal set consists of some
58   number _VKI_NSIG_WORDS of 32- or 64-bit words.  Because the kernel
59   itself has some indexing scheme to set/clear individual bits in the
60   set, we must make sure we use the same layout/scheme: where this
61   requirement bites us is in the VG_(sigfillset) etc functions in
62   m_libcsignal.c.  So we check carefully here that it's all sensible.
63*/
64void VG_(vki_do_initial_consistency_checks) ( void )
65{
66   /* --- Platform-independent checks on signal sets --- */
67
68   vki_sigset_t set;
69   // Set's size must agree with _VKI_NSIG
70   vg_assert( 8 * sizeof(set) == _VKI_NSIG );
71   // Set's word size must agree with _VKI_NSIG_BPW
72   vg_assert( 8 * sizeof(set.sig[0]) == _VKI_NSIG_BPW );
73   // The set elements are 32- or 64-bit
74   vg_assert( _VKI_NSIG_BPW == 32 || _VKI_NSIG_BPW == 64 );
75
76   /* --- Platform-specific checks on signal sets --- */
77
78#  if defined(VGO_linux)
79   /* nothing to check */
80#  elif defined(VGP_x86_darwin) || defined(VGP_amd64_darwin)
81   vg_assert(_VKI_NSIG == NSIG);
82   vg_assert(_VKI_NSIG == 32);
83   vg_assert(_VKI_NSIG_WORDS == 1);
84   vg_assert(sizeof(sigset_t) /* defined by Darwin */
85             == sizeof(vki_sigset_t) /* what we actually use */);
86#  else
87#    error "Unknown plat"
88#  endif
89
90   /* --- Platform-specific checks on sigactions --- */
91
92#  if defined(VGO_linux)
93   /* the toK- and fromK- forms are identical */
94   vg_assert( sizeof(vki_sigaction_toK_t)
95              == sizeof(vki_sigaction_fromK_t) );
96#  elif defined(VGO_darwin)
97   /* the toK- and fromK- forms differ by one function-pointer field
98      (sa_tramp) */
99   vg_assert( sizeof(vki_sigaction_toK_t)
100              == sizeof(vki_sigaction_fromK_t) + sizeof(void*) );
101
102   vg_assert(sizeof(struct sigaction) == sizeof(vki_sigaction_fromK_t));
103   vg_assert(sizeof(struct __sigaction) == sizeof(vki_sigaction_toK_t));
104   { struct __sigaction    t1;
105     vki_sigaction_toK_t   t2;
106     struct sigaction      f1;
107     vki_sigaction_fromK_t f2;
108     vg_assert(sizeof(t1.sa_handler) == sizeof(t2.ksa_handler));
109     vg_assert(sizeof(t1.sa_tramp)   == sizeof(t2.sa_tramp));
110     vg_assert(sizeof(t1.sa_mask)    == sizeof(t2.sa_mask));
111     vg_assert(sizeof(t1.sa_flags)   == sizeof(t2.sa_flags));
112     vg_assert(sizeof(f1.sa_handler) == sizeof(f2.ksa_handler));
113     vg_assert(sizeof(f1.sa_mask)    == sizeof(f2.sa_mask));
114     vg_assert(sizeof(f1.sa_flags)   == sizeof(f2.sa_flags));
115#    if 0
116     vg_assert(offsetof(t1,sa_handler) == offsetof(t2.ksa_handler));
117     vg_assert(offsetof(t1.sa_tramp)   == offsetof(t2.sa_tramp));
118     vg_assert(offsetof(t1.sa_mask)    == offsetof(t2.sa_mask));
119     vg_assert(offsetof(t1.sa_flags)   == offsetof(t2.sa_flags));
120     vg_assert(offsetof(f1.sa_handler) == offsetof(f2.ksa_handler));
121     vg_assert(offsetof(f1.sa_mask)    == offsetof(f2.sa_mask));
122     vg_assert(offsetof(f1.sa_flags)   == offsetof(f2.sa_flags));
123#    endif
124   }
125   /* also .. */
126   /* VKI_SET_SIGMASK is hardwired into syscall-x86-darwin.S and
127      syscall-amd64-darwin.S */
128   vg_assert(VKI_SIG_SETMASK == 3);
129
130#  else
131#     error "Unknown OS"
132#  endif
133}
134
135
136/*--------------------------------------------------------------------*/
137/*--- end                                                  m_vki.c ---*/
138/*--------------------------------------------------------------------*/
139