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) 2006-2013 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) \
46 || defined(VGP_arm64_linux)
47 unsigned long VKI_PAGE_SHIFT = 12;
48 unsigned long VKI_PAGE_SIZE = 1UL << 12;
49 #endif
50
51
52 /* Do initial consistency checks on some of the definitions to do with
53 signals (vki_sigset_t and vki_sigaction_{toK,fromK}_t). This stuff
54 is fragile enough that it's important to check at startup that
55 the world looks like what we expect it to look like.
56
57 The most important thing is to check that the definition of signal
58 sets for this platform is right. A signal set consists of some
59 number _VKI_NSIG_WORDS of 32- or 64-bit words. Because the kernel
60 itself has some indexing scheme to set/clear individual bits in the
61 set, we must make sure we use the same layout/scheme: where this
62 requirement bites us is in the VG_(sigfillset) etc functions in
63 m_libcsignal.c. So we check carefully here that it's all sensible.
64 */
VG_(vki_do_initial_consistency_checks)65 void VG_(vki_do_initial_consistency_checks) ( void )
66 {
67 /* --- Platform-independent checks on signal sets --- */
68
69 vki_sigset_t set;
70 // Set's size must agree with _VKI_NSIG
71 vg_assert( 8 * sizeof(set) == _VKI_NSIG );
72 // Set's word size must agree with _VKI_NSIG_BPW
73 vg_assert( 8 * sizeof(set.sig[0]) == _VKI_NSIG_BPW );
74 // The set elements are 32- or 64-bit
75 vg_assert( _VKI_NSIG_BPW == 32 || _VKI_NSIG_BPW == 64 );
76
77 /* --- Platform-specific checks on signal sets --- */
78
79 # if defined(VGO_linux)
80 /* nothing to check */
81 # elif defined(VGP_x86_darwin) || defined(VGP_amd64_darwin)
82 vg_assert(_VKI_NSIG == NSIG);
83 vg_assert(_VKI_NSIG == 32);
84 vg_assert(_VKI_NSIG_WORDS == 1);
85 vg_assert(sizeof(sigset_t) /* defined by Darwin */
86 == sizeof(vki_sigset_t) /* what we actually use */);
87 # else
88 # error "Unknown plat"
89 # endif
90
91 /* --- Platform-specific checks on sigactions --- */
92
93 # if defined(VGO_linux)
94 /* the toK- and fromK- forms are identical */
95 vg_assert( sizeof(vki_sigaction_toK_t)
96 == sizeof(vki_sigaction_fromK_t) );
97 # elif defined(VGO_darwin)
98 /* the toK- and fromK- forms differ by one function-pointer field
99 (sa_tramp) */
100 vg_assert( sizeof(vki_sigaction_toK_t)
101 == sizeof(vki_sigaction_fromK_t) + sizeof(void*) );
102
103 vg_assert(sizeof(struct sigaction) == sizeof(vki_sigaction_fromK_t));
104 vg_assert(sizeof(struct __sigaction) == sizeof(vki_sigaction_toK_t));
105 { struct __sigaction t1;
106 vki_sigaction_toK_t t2;
107 struct sigaction f1;
108 vki_sigaction_fromK_t f2;
109 vg_assert(sizeof(t1.sa_handler) == sizeof(t2.ksa_handler));
110 vg_assert(sizeof(t1.sa_tramp) == sizeof(t2.sa_tramp));
111 vg_assert(sizeof(t1.sa_mask) == sizeof(t2.sa_mask));
112 vg_assert(sizeof(t1.sa_flags) == sizeof(t2.sa_flags));
113 vg_assert(sizeof(f1.sa_handler) == sizeof(f2.ksa_handler));
114 vg_assert(sizeof(f1.sa_mask) == sizeof(f2.sa_mask));
115 vg_assert(sizeof(f1.sa_flags) == sizeof(f2.sa_flags));
116 # if 0
117 vg_assert(offsetof(t1,sa_handler) == offsetof(t2.ksa_handler));
118 vg_assert(offsetof(t1.sa_tramp) == offsetof(t2.sa_tramp));
119 vg_assert(offsetof(t1.sa_mask) == offsetof(t2.sa_mask));
120 vg_assert(offsetof(t1.sa_flags) == offsetof(t2.sa_flags));
121 vg_assert(offsetof(f1.sa_handler) == offsetof(f2.ksa_handler));
122 vg_assert(offsetof(f1.sa_mask) == offsetof(f2.sa_mask));
123 vg_assert(offsetof(f1.sa_flags) == offsetof(f2.sa_flags));
124 # endif
125 }
126 /* also .. */
127 /* VKI_SET_SIGMASK is hardwired into syscall-x86-darwin.S and
128 syscall-amd64-darwin.S */
129 vg_assert(VKI_SIG_SETMASK == 3);
130
131 # else
132 # error "Unknown OS"
133 # endif
134 }
135
136
137 /*--------------------------------------------------------------------*/
138 /*--- end m_vki.c ---*/
139 /*--------------------------------------------------------------------*/
140