njn | de62cbf | 2005-06-10 22:08:14 +0000 | [diff] [blame] | 1 | |
| 2 | /*--------------------------------------------------------------------*/ |
| 3 | /*--- Signal-related libc stuff. m_libcsignal.c ---*/ |
| 4 | /*--------------------------------------------------------------------*/ |
| 5 | |
| 6 | /* |
| 7 | This file is part of Valgrind, a dynamic binary instrumentation |
| 8 | framework. |
| 9 | |
sewardj | 0f157dd | 2013-10-18 14:27:36 +0000 | [diff] [blame] | 10 | Copyright (C) 2000-2013 Julian Seward |
njn | de62cbf | 2005-06-10 22:08:14 +0000 | [diff] [blame] | 11 | jseward@acm.org |
| 12 | |
| 13 | This program is free software; you can redistribute it and/or |
| 14 | modify it under the terms of the GNU General Public License as |
| 15 | published by the Free Software Foundation; either version 2 of the |
| 16 | License, or (at your option) any later version. |
| 17 | |
| 18 | This program is distributed in the hope that it will be useful, but |
| 19 | WITHOUT ANY WARRANTY; without even the implied warranty of |
| 20 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 21 | General Public License for more details. |
| 22 | |
| 23 | You should have received a copy of the GNU General Public License |
| 24 | along with this program; if not, write to the Free Software |
| 25 | Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA |
| 26 | 02111-1307, USA. |
| 27 | |
| 28 | The GNU General Public License is contained in the file COPYING. |
| 29 | */ |
| 30 | |
njn | c7561b9 | 2005-06-19 01:24:32 +0000 | [diff] [blame] | 31 | #include "pub_core_basics.h" |
sewardj | 1383bdd | 2006-10-17 01:30:47 +0000 | [diff] [blame] | 32 | #include "pub_core_debuglog.h" |
sewardj | 4cfea4f | 2006-10-14 19:26:10 +0000 | [diff] [blame] | 33 | #include "pub_core_vki.h" |
sewardj | 1383bdd | 2006-10-17 01:30:47 +0000 | [diff] [blame] | 34 | #include "pub_core_vkiscnums.h" |
njn | de62cbf | 2005-06-10 22:08:14 +0000 | [diff] [blame] | 35 | #include "pub_core_libcbase.h" |
| 36 | #include "pub_core_libcassert.h" |
njn | 9abd608 | 2005-06-17 21:31:45 +0000 | [diff] [blame] | 37 | #include "pub_core_syscall.h" |
sewardj | 1383bdd | 2006-10-17 01:30:47 +0000 | [diff] [blame] | 38 | #include "pub_core_libcsignal.h" /* self */ |
njn | de62cbf | 2005-06-10 22:08:14 +0000 | [diff] [blame] | 39 | |
njn | f76d27a | 2009-05-28 01:53:07 +0000 | [diff] [blame] | 40 | /* IMPORTANT: on Darwin it is essential to use the _nocancel versions |
| 41 | of syscalls rather than the vanilla version, if a _nocancel version |
| 42 | is available. See docs/internals/Darwin-notes.txt for the reason |
| 43 | why. */ |
| 44 | |
njn | de62cbf | 2005-06-10 22:08:14 +0000 | [diff] [blame] | 45 | /* sigemptyset, sigfullset, sigaddset and sigdelset return 0 on |
| 46 | success and -1 on error. */ |
njn | cda2f0f | 2009-05-18 02:12:08 +0000 | [diff] [blame] | 47 | /* In the sigset routines below, be aware that _VKI_NSIG_BPW can be |
| 48 | either 32 or 64, and hence the sig[] words can either be 32- or |
| 49 | 64-bits. And which they are it doesn't necessarily follow from the |
| 50 | host word size. */ |
njn | de62cbf | 2005-06-10 22:08:14 +0000 | [diff] [blame] | 51 | |
| 52 | Int VG_(sigfillset)( vki_sigset_t* set ) |
| 53 | { |
| 54 | Int i; |
| 55 | if (set == NULL) |
| 56 | return -1; |
| 57 | for (i = 0; i < _VKI_NSIG_WORDS; i++) |
njn | cda2f0f | 2009-05-18 02:12:08 +0000 | [diff] [blame] | 58 | set->sig[i] = ~0; |
njn | de62cbf | 2005-06-10 22:08:14 +0000 | [diff] [blame] | 59 | return 0; |
| 60 | } |
| 61 | |
| 62 | Int VG_(sigemptyset)( vki_sigset_t* set ) |
| 63 | { |
| 64 | Int i; |
| 65 | if (set == NULL) |
| 66 | return -1; |
| 67 | for (i = 0; i < _VKI_NSIG_WORDS; i++) |
njn | cda2f0f | 2009-05-18 02:12:08 +0000 | [diff] [blame] | 68 | set->sig[i] = 0; |
njn | de62cbf | 2005-06-10 22:08:14 +0000 | [diff] [blame] | 69 | return 0; |
| 70 | } |
| 71 | |
| 72 | Bool VG_(isemptysigset)( const vki_sigset_t* set ) |
| 73 | { |
| 74 | Int i; |
| 75 | vg_assert(set != NULL); |
| 76 | for (i = 0; i < _VKI_NSIG_WORDS; i++) |
njn | cda2f0f | 2009-05-18 02:12:08 +0000 | [diff] [blame] | 77 | if (set->sig[i] != 0) return False; |
njn | de62cbf | 2005-06-10 22:08:14 +0000 | [diff] [blame] | 78 | return True; |
| 79 | } |
| 80 | |
| 81 | Bool VG_(isfullsigset)( const vki_sigset_t* set ) |
| 82 | { |
| 83 | Int i; |
| 84 | vg_assert(set != NULL); |
| 85 | for (i = 0; i < _VKI_NSIG_WORDS; i++) |
njn | cda2f0f | 2009-05-18 02:12:08 +0000 | [diff] [blame] | 86 | if (set->sig[i] != ~0) return False; |
njn | de62cbf | 2005-06-10 22:08:14 +0000 | [diff] [blame] | 87 | return True; |
| 88 | } |
| 89 | |
| 90 | Bool VG_(iseqsigset)( const vki_sigset_t* set1, const vki_sigset_t* set2 ) |
| 91 | { |
| 92 | Int i; |
| 93 | vg_assert(set1 != NULL && set2 != NULL); |
| 94 | for (i = 0; i < _VKI_NSIG_WORDS; i++) |
| 95 | if (set1->sig[i] != set2->sig[i]) return False; |
| 96 | return True; |
| 97 | } |
| 98 | |
| 99 | |
| 100 | Int VG_(sigaddset)( vki_sigset_t* set, Int signum ) |
| 101 | { |
| 102 | if (set == NULL) |
| 103 | return -1; |
| 104 | if (signum < 1 || signum > _VKI_NSIG) |
| 105 | return -1; |
| 106 | signum--; |
njn | cda2f0f | 2009-05-18 02:12:08 +0000 | [diff] [blame] | 107 | set->sig[signum / _VKI_NSIG_BPW] |= (1ULL << (signum % _VKI_NSIG_BPW)); |
njn | de62cbf | 2005-06-10 22:08:14 +0000 | [diff] [blame] | 108 | return 0; |
| 109 | } |
| 110 | |
| 111 | Int VG_(sigdelset)( vki_sigset_t* set, Int signum ) |
| 112 | { |
| 113 | if (set == NULL) |
| 114 | return -1; |
| 115 | if (signum < 1 || signum > _VKI_NSIG) |
| 116 | return -1; |
| 117 | signum--; |
njn | cda2f0f | 2009-05-18 02:12:08 +0000 | [diff] [blame] | 118 | set->sig[signum / _VKI_NSIG_BPW] &= ~(1ULL << (signum % _VKI_NSIG_BPW)); |
njn | de62cbf | 2005-06-10 22:08:14 +0000 | [diff] [blame] | 119 | return 0; |
| 120 | } |
| 121 | |
| 122 | Int VG_(sigismember) ( const vki_sigset_t* set, Int signum ) |
| 123 | { |
| 124 | if (set == NULL) |
| 125 | return 0; |
| 126 | if (signum < 1 || signum > _VKI_NSIG) |
| 127 | return 0; |
| 128 | signum--; |
| 129 | if (1 & ((set->sig[signum / _VKI_NSIG_BPW]) >> (signum % _VKI_NSIG_BPW))) |
| 130 | return 1; |
| 131 | else |
| 132 | return 0; |
| 133 | } |
| 134 | |
njn | de62cbf | 2005-06-10 22:08:14 +0000 | [diff] [blame] | 135 | /* Add all signals in src to dst. */ |
| 136 | void VG_(sigaddset_from_set)( vki_sigset_t* dst, vki_sigset_t* src ) |
| 137 | { |
| 138 | Int i; |
| 139 | vg_assert(dst != NULL && src != NULL); |
| 140 | for (i = 0; i < _VKI_NSIG_WORDS; i++) |
| 141 | dst->sig[i] |= src->sig[i]; |
| 142 | } |
| 143 | |
| 144 | /* Remove all signals in src from dst. */ |
| 145 | void VG_(sigdelset_from_set)( vki_sigset_t* dst, vki_sigset_t* src ) |
| 146 | { |
| 147 | Int i; |
| 148 | vg_assert(dst != NULL && src != NULL); |
| 149 | for (i = 0; i < _VKI_NSIG_WORDS; i++) |
| 150 | dst->sig[i] &= ~(src->sig[i]); |
| 151 | } |
| 152 | |
njn | cda2f0f | 2009-05-18 02:12:08 +0000 | [diff] [blame] | 153 | /* dst = dst `intersect` src. */ |
| 154 | void VG_(sigintersectset)( vki_sigset_t* dst, vki_sigset_t* src ) |
| 155 | { |
| 156 | Int i; |
| 157 | vg_assert(dst != NULL && src != NULL); |
| 158 | for (i = 0; i < _VKI_NSIG_WORDS; i++) |
| 159 | dst->sig[i] &= src->sig[i]; |
| 160 | } |
| 161 | |
| 162 | /* dst = ~src */ |
| 163 | void VG_(sigcomplementset)( vki_sigset_t* dst, vki_sigset_t* src ) |
| 164 | { |
| 165 | Int i; |
| 166 | vg_assert(dst != NULL && src != NULL); |
| 167 | for (i = 0; i < _VKI_NSIG_WORDS; i++) |
| 168 | dst->sig[i] = ~ src->sig[i]; |
| 169 | } |
| 170 | |
njn | de62cbf | 2005-06-10 22:08:14 +0000 | [diff] [blame] | 171 | |
| 172 | /* The functions sigaction, sigprocmask, sigpending and sigsuspend |
| 173 | return 0 on success and -1 on error. |
| 174 | */ |
| 175 | Int VG_(sigprocmask)( Int how, const vki_sigset_t* set, vki_sigset_t* oldset) |
| 176 | { |
sewardj | 6e9de46 | 2011-06-28 07:25:29 +0000 | [diff] [blame] | 177 | # if defined(VGO_linux) |
njn | cda2f0f | 2009-05-18 02:12:08 +0000 | [diff] [blame] | 178 | # if defined(__NR_rt_sigprocmask) |
njn | de62cbf | 2005-06-10 22:08:14 +0000 | [diff] [blame] | 179 | SysRes res = VG_(do_syscall4)(__NR_rt_sigprocmask, |
| 180 | how, (UWord)set, (UWord)oldset, |
| 181 | _VKI_NSIG_WORDS * sizeof(UWord)); |
njn | cda2f0f | 2009-05-18 02:12:08 +0000 | [diff] [blame] | 182 | # else |
| 183 | SysRes res = VG_(do_syscall3)(__NR_sigprocmask, |
| 184 | how, (UWord)set, (UWord)oldset); |
| 185 | # endif |
| 186 | |
njn | f76d27a | 2009-05-28 01:53:07 +0000 | [diff] [blame] | 187 | # elif defined(VGO_darwin) |
| 188 | /* On Darwin, __NR_sigprocmask appears to affect the entire |
| 189 | process, not just this thread. Hence need to use |
| 190 | __NR___pthread_sigmask instead. */ |
| 191 | SysRes res = VG_(do_syscall3)(__NR___pthread_sigmask, |
| 192 | how, (UWord)set, (UWord)oldset); |
njn | cda2f0f | 2009-05-18 02:12:08 +0000 | [diff] [blame] | 193 | # else |
| 194 | # error "Unknown OS" |
| 195 | # endif |
| 196 | return sr_isError(res) ? -1 : 0; |
njn | de62cbf | 2005-06-10 22:08:14 +0000 | [diff] [blame] | 197 | } |
| 198 | |
| 199 | |
njn | f76d27a | 2009-05-28 01:53:07 +0000 | [diff] [blame] | 200 | #if defined(VGO_darwin) |
| 201 | /* A helper function for sigaction on Darwin. */ |
| 202 | static |
| 203 | void darwin_signal_demux(void* a1, UWord a2, UWord a3, void* a4, void* a5) { |
| 204 | VG_(debugLog)(2, "libcsignal", |
| 205 | "PRE demux sig, a2 = %lu, signo = %lu\n", a2, a3); |
| 206 | if (a2 == 1) |
| 207 | ((void(*)(int))a1) (a3); |
| 208 | else |
| 209 | ((void(*)(int,void*,void*))a1) (a3,a4,a5); |
| 210 | VG_(debugLog)(2, "libcsignal", |
| 211 | "POST demux sig, a2 = %lu, signo = %lu\n", a2, a3); |
| 212 | VG_(do_syscall2)(__NR_sigreturn, (UWord)a5, 0x1E); |
| 213 | /* NOTREACHED */ |
| 214 | __asm__ __volatile__("ud2"); |
| 215 | } |
| 216 | #endif |
| 217 | |
njn | cda2f0f | 2009-05-18 02:12:08 +0000 | [diff] [blame] | 218 | Int VG_(sigaction) ( Int signum, |
| 219 | const vki_sigaction_toK_t* act, |
| 220 | vki_sigaction_fromK_t* oldact) |
njn | de62cbf | 2005-06-10 22:08:14 +0000 | [diff] [blame] | 221 | { |
sewardj | 6e9de46 | 2011-06-28 07:25:29 +0000 | [diff] [blame] | 222 | # if defined(VGO_linux) |
njn | cda2f0f | 2009-05-18 02:12:08 +0000 | [diff] [blame] | 223 | /* Normal case: vki_sigaction_toK_t and vki_sigaction_fromK_t are |
| 224 | identical types. */ |
njn | de62cbf | 2005-06-10 22:08:14 +0000 | [diff] [blame] | 225 | SysRes res = VG_(do_syscall4)(__NR_rt_sigaction, |
| 226 | signum, (UWord)act, (UWord)oldact, |
| 227 | _VKI_NSIG_WORDS * sizeof(UWord)); |
njn | cda2f0f | 2009-05-18 02:12:08 +0000 | [diff] [blame] | 228 | return sr_isError(res) ? -1 : 0; |
| 229 | |
njn | f76d27a | 2009-05-28 01:53:07 +0000 | [diff] [blame] | 230 | # elif defined(VGO_darwin) |
| 231 | /* If we're passing a new action to the kernel, make a copy of the |
| 232 | new action, install our own sa_tramp field in it, and ignore |
| 233 | whatever we were provided with. This is OK because all the |
| 234 | sigaction requests come from m_signals, and are not directly |
| 235 | what the client program requested, so there is no chance that we |
| 236 | will inadvertantly ignore the sa_tramp field requested by the |
| 237 | client. (In fact m_signals does ignore it when building signal |
| 238 | frames for the client, but that's a completely different |
| 239 | matter). |
| 240 | |
| 241 | If we're receiving an old action from the kernel, be very |
| 242 | paranoid and make sure the kernel doesn't trash bits of memory |
| 243 | that we don't expect it to. */ |
| 244 | SysRes res; |
| 245 | |
| 246 | vki_sigaction_toK_t actCopy; |
| 247 | struct { |
| 248 | ULong before[2]; |
| 249 | vki_sigaction_fromK_t oa; |
| 250 | ULong after[2]; |
| 251 | } |
| 252 | oldactCopy; |
| 253 | |
| 254 | vki_sigaction_toK_t* real_act; |
| 255 | vki_sigaction_fromK_t* real_oldact; |
| 256 | |
| 257 | real_act = act ? &actCopy : NULL; |
| 258 | real_oldact = oldact ? &oldactCopy.oa : NULL; |
| 259 | VG_(memset)(&oldactCopy, 0x55, sizeof(oldactCopy)); |
| 260 | if (real_act) { |
| 261 | *real_act = *act; |
| 262 | real_act->sa_tramp = (void*)&darwin_signal_demux; |
| 263 | } |
| 264 | res = VG_(do_syscall3)(__NR_sigaction, |
| 265 | signum, (UWord)real_act, (UWord)real_oldact); |
| 266 | if (real_oldact) { |
| 267 | vg_assert(oldactCopy.before[0] == 0x5555555555555555ULL); |
| 268 | vg_assert(oldactCopy.before[1] == 0x5555555555555555ULL); |
| 269 | vg_assert(oldactCopy.after[0] == 0x5555555555555555ULL); |
| 270 | vg_assert(oldactCopy.after[1] == 0x5555555555555555ULL); |
| 271 | *oldact = *real_oldact; |
| 272 | } |
| 273 | return sr_isError(res) ? -1 : 0; |
| 274 | |
njn | cda2f0f | 2009-05-18 02:12:08 +0000 | [diff] [blame] | 275 | # else |
| 276 | # error "Unsupported OS" |
| 277 | # endif |
| 278 | } |
| 279 | |
| 280 | |
| 281 | /* See explanation in pub_core_libcsignal.h. */ |
| 282 | void |
| 283 | VG_(convert_sigaction_fromK_to_toK)( vki_sigaction_fromK_t* fromK, |
| 284 | /*OUT*/vki_sigaction_toK_t* toK ) |
| 285 | { |
sewardj | 6e9de46 | 2011-06-28 07:25:29 +0000 | [diff] [blame] | 286 | # if defined(VGO_linux) |
njn | cda2f0f | 2009-05-18 02:12:08 +0000 | [diff] [blame] | 287 | *toK = *fromK; |
njn | f76d27a | 2009-05-28 01:53:07 +0000 | [diff] [blame] | 288 | # elif defined(VGO_darwin) |
| 289 | toK->ksa_handler = fromK->ksa_handler; |
| 290 | toK->sa_tramp = NULL; /* the cause of all the difficulty */ |
| 291 | toK->sa_mask = fromK->sa_mask; |
| 292 | toK->sa_flags = fromK->sa_flags; |
njn | cda2f0f | 2009-05-18 02:12:08 +0000 | [diff] [blame] | 293 | # else |
| 294 | # error "Unsupported OS" |
| 295 | # endif |
njn | de62cbf | 2005-06-10 22:08:14 +0000 | [diff] [blame] | 296 | } |
| 297 | |
| 298 | |
njn | de62cbf | 2005-06-10 22:08:14 +0000 | [diff] [blame] | 299 | Int VG_(kill)( Int pid, Int signo ) |
| 300 | { |
sewardj | 6e9de46 | 2011-06-28 07:25:29 +0000 | [diff] [blame] | 301 | # if defined(VGO_linux) |
njn | de62cbf | 2005-06-10 22:08:14 +0000 | [diff] [blame] | 302 | SysRes res = VG_(do_syscall2)(__NR_kill, pid, signo); |
njn | f76d27a | 2009-05-28 01:53:07 +0000 | [diff] [blame] | 303 | # elif defined(VGO_darwin) |
| 304 | SysRes res = VG_(do_syscall3)(__NR_kill, |
| 305 | pid, signo, 1/*posix-compliant*/); |
| 306 | # else |
| 307 | # error "Unsupported OS" |
| 308 | # endif |
njn | cda2f0f | 2009-05-18 02:12:08 +0000 | [diff] [blame] | 309 | return sr_isError(res) ? -1 : 0; |
njn | de62cbf | 2005-06-10 22:08:14 +0000 | [diff] [blame] | 310 | } |
| 311 | |
njn | 99109fe | 2009-05-20 07:10:48 +0000 | [diff] [blame] | 312 | Int VG_(tkill)( Int lwpid, Int signo ) |
njn | de62cbf | 2005-06-10 22:08:14 +0000 | [diff] [blame] | 313 | { |
njn | cda2f0f | 2009-05-18 02:12:08 +0000 | [diff] [blame] | 314 | # if defined(__NR_tkill) |
njn | de62cbf | 2005-06-10 22:08:14 +0000 | [diff] [blame] | 315 | SysRes res = VG_(mk_SysRes_Error)(VKI_ENOSYS); |
njn | 99109fe | 2009-05-20 07:10:48 +0000 | [diff] [blame] | 316 | res = VG_(do_syscall2)(__NR_tkill, lwpid, signo); |
njn | cda2f0f | 2009-05-18 02:12:08 +0000 | [diff] [blame] | 317 | if (sr_isError(res) && sr_Err(res) == VKI_ENOSYS) |
njn | 99109fe | 2009-05-20 07:10:48 +0000 | [diff] [blame] | 318 | res = VG_(do_syscall2)(__NR_kill, lwpid, signo); |
njn | cda2f0f | 2009-05-18 02:12:08 +0000 | [diff] [blame] | 319 | return sr_isError(res) ? -1 : 0; |
| 320 | |
njn | f76d27a | 2009-05-28 01:53:07 +0000 | [diff] [blame] | 321 | # elif defined(VGO_darwin) |
| 322 | // Note that the __pthread_kill syscall takes a Mach thread, not a pthread. |
| 323 | SysRes res; |
| 324 | res = VG_(do_syscall2)(__NR___pthread_kill, lwpid, signo); |
| 325 | return sr_isError(res) ? -1 : 0; |
| 326 | |
njn | cda2f0f | 2009-05-18 02:12:08 +0000 | [diff] [blame] | 327 | # else |
| 328 | # error "Unsupported plat" |
| 329 | # endif |
njn | de62cbf | 2005-06-10 22:08:14 +0000 | [diff] [blame] | 330 | } |
| 331 | |
njn | cda2f0f | 2009-05-18 02:12:08 +0000 | [diff] [blame] | 332 | /* ---------------------- sigtimedwait_zero ----------------------- */ |
sewardj | 1383bdd | 2006-10-17 01:30:47 +0000 | [diff] [blame] | 333 | |
| 334 | /* A cut-down version of POSIX sigtimedwait: poll for pending signals |
| 335 | mentioned in the sigset_t, and if any are present, select one |
| 336 | arbitrarily, return its number (which must be > 0), and put |
| 337 | auxiliary info about it in the siginfo_t, and make it |
| 338 | not-pending-any-more. If none are pending, return zero. The _zero |
| 339 | refers to the fact that there is zero timeout, so if no signals are |
| 340 | pending it returns immediately. Perhaps a better name would be |
| 341 | 'sigpoll'. Returns -1 on error, 0 if no signals pending, and n > 0 |
| 342 | if signal n was selected. |
| 343 | |
| 344 | The Linux implementation is trivial: do the corresponding syscall. |
| 345 | |
sewardj | 6e9de46 | 2011-06-28 07:25:29 +0000 | [diff] [blame] | 346 | The Darwin implementation is horrible and probably broken in a dozen |
sewardj | 1383bdd | 2006-10-17 01:30:47 +0000 | [diff] [blame] | 347 | obscure ways. I suspect it's only thread-safe because V forces |
| 348 | single-threadedness. */ |
| 349 | |
njn | cda2f0f | 2009-05-18 02:12:08 +0000 | [diff] [blame] | 350 | /* ---------- sigtimedwait_zero: Linux ----------- */ |
| 351 | |
sewardj | 1383bdd | 2006-10-17 01:30:47 +0000 | [diff] [blame] | 352 | #if defined(VGO_linux) |
| 353 | Int VG_(sigtimedwait_zero)( const vki_sigset_t *set, |
| 354 | vki_siginfo_t *info ) |
| 355 | { |
| 356 | static const struct vki_timespec zero = { 0, 0 }; |
| 357 | SysRes res = VG_(do_syscall4)(__NR_rt_sigtimedwait, (UWord)set, (UWord)info, |
| 358 | (UWord)&zero, sizeof(*set)); |
njn | cda2f0f | 2009-05-18 02:12:08 +0000 | [diff] [blame] | 359 | return sr_isError(res) ? -1 : sr_Res(res); |
sewardj | 1383bdd | 2006-10-17 01:30:47 +0000 | [diff] [blame] | 360 | } |
| 361 | |
njn | f76d27a | 2009-05-28 01:53:07 +0000 | [diff] [blame] | 362 | /* ---------- sigtimedwait_zero: Darwin ----------- */ |
| 363 | |
| 364 | #elif defined(VGO_darwin) |
| 365 | |
| 366 | //static void show_set ( HChar* str, const vki_sigset_t* set ) { |
| 367 | // Int i; |
| 368 | // VG_(printf)("%s { ", str); |
| 369 | // for (i = 1; i <= _VKI_NSIG; i++) { |
| 370 | // if (VG_(sigismember)(set, i)) |
| 371 | // VG_(printf)("%u ", i); |
| 372 | // } |
| 373 | // VG_(printf)("}\n"); |
| 374 | //} |
| 375 | |
sewardj | 6e9de46 | 2011-06-28 07:25:29 +0000 | [diff] [blame] | 376 | /* The general idea is: |
| 377 | - use sigpending to find out which signals are pending |
| 378 | - choose one |
| 379 | - temporarily set its handler to sigtimedwait_zero_handler |
| 380 | - use sigsuspend atomically unblock it and wait for the signal. |
| 381 | Upon return, sigsuspend restores the signal mask to what it |
| 382 | was to start with. |
| 383 | - Restore the handler for the signal to whatever it was before. |
| 384 | */ |
| 385 | |
| 386 | /* A signal handler which does nothing (it doesn't need to). It does |
| 387 | however check that it's not handing a sync signal for which |
| 388 | returning is meaningless. */ |
njn | f76d27a | 2009-05-28 01:53:07 +0000 | [diff] [blame] | 389 | static void sigtimedwait_zero_handler ( Int sig ) |
| 390 | { |
| 391 | /* XXX this is wrong -- get rid of these. We could |
| 392 | get _any_ signal here */ |
| 393 | vg_assert(sig != VKI_SIGILL); |
| 394 | vg_assert(sig != VKI_SIGSEGV); |
| 395 | vg_assert(sig != VKI_SIGBUS); |
| 396 | vg_assert(sig != VKI_SIGTRAP); |
| 397 | /* do nothing */ |
| 398 | } |
| 399 | |
| 400 | Int VG_(sigtimedwait_zero)( const vki_sigset_t *set, |
| 401 | vki_siginfo_t *info ) |
| 402 | { |
| 403 | const Bool debug = False; |
| 404 | Int i, ir; |
| 405 | SysRes sr; |
| 406 | vki_sigset_t pending, blocked, allbutone; |
| 407 | vki_sigaction_toK_t sa, saved_sa2; |
| 408 | vki_sigaction_fromK_t saved_sa; |
| 409 | |
| 410 | //show_set("STWZ: looking for", set); |
| 411 | |
| 412 | /* Find out what's pending: Darwin sigpending */ |
| 413 | sr = VG_(do_syscall1)(__NR_sigpending, (UWord)&pending); |
| 414 | vg_assert(!sr_isError(sr)); |
| 415 | |
| 416 | /* don't try for signals not in 'set' */ |
| 417 | /* pending = pending `intersect` set */ |
| 418 | VG_(sigintersectset)(&pending, (vki_sigset_t*)set); |
| 419 | |
| 420 | /* don't try for signals not blocked at the moment */ |
| 421 | ir = VG_(sigprocmask)(VKI_SIG_SETMASK, NULL, &blocked); |
| 422 | vg_assert(ir == 0); |
| 423 | |
| 424 | /* pending = pending `intersect` blocked */ |
| 425 | VG_(sigintersectset)(&pending, &blocked); |
| 426 | |
| 427 | /* decide which signal we're going to snarf */ |
| 428 | for (i = 1; i < _VKI_NSIG; i++) |
| 429 | if (VG_(sigismember)(&pending,i)) |
| 430 | break; |
| 431 | |
| 432 | if (i == _VKI_NSIG) |
| 433 | return 0; |
| 434 | |
| 435 | if (debug) |
| 436 | VG_(debugLog)(0, "libcsignal", |
| 437 | "sigtimedwait_zero: snarfing signal %d\n", i ); |
| 438 | |
| 439 | /* fetch signal i. |
| 440 | pre: i is blocked and pending |
| 441 | pre: we are the only thread running |
| 442 | */ |
| 443 | /* Set up alternative signal handler */ |
| 444 | VG_(sigfillset)(&sa.sa_mask); |
| 445 | sa.ksa_handler = &sigtimedwait_zero_handler; |
| 446 | sa.sa_flags = 0; |
| 447 | ir = VG_(sigaction)(i, &sa, &saved_sa); |
| 448 | vg_assert(ir == 0); |
| 449 | |
| 450 | /* Switch signal masks and wait for the signal. This should happen |
| 451 | immediately, since we've already established it is pending and |
| 452 | blocked. */ |
| 453 | VG_(sigfillset)(&allbutone); |
| 454 | VG_(sigdelset)(&allbutone, i); |
| 455 | /* Note: pass the sig mask by value here, not reference (!) */ |
| 456 | vg_assert(_VKI_NSIG_WORDS == 1); |
| 457 | sr = VG_(do_syscall3)(__NR_sigsuspend_nocancel, |
| 458 | (UWord)allbutone.sig[0], 0,0); |
| 459 | if (debug) |
| 460 | VG_(debugLog)(0, "libcsignal", |
| 461 | "sigtimedwait_zero: sigsuspend got " |
| 462 | "res: %s %#lx\n", |
| 463 | sr_isError(sr) ? "FAIL" : "SUCCESS", |
| 464 | sr_isError(sr) ? sr_Err(sr) : sr_Res(sr)); |
| 465 | vg_assert(sr_isError(sr)); |
| 466 | vg_assert(sr_Err(sr) == VKI_EINTR); |
| 467 | |
| 468 | /* Restore signal's handler to whatever it was before */ |
| 469 | VG_(convert_sigaction_fromK_to_toK)( &saved_sa, &saved_sa2 ); |
| 470 | ir = VG_(sigaction)(i, &saved_sa2, NULL); |
| 471 | vg_assert(ir == 0); |
| 472 | |
| 473 | /* This is bogus - we could get more info from the sighandler. */ |
| 474 | VG_(memset)( info, 0, sizeof(*info) ); |
| 475 | info->si_signo = i; |
| 476 | |
| 477 | return i; |
| 478 | } |
| 479 | |
sewardj | 1383bdd | 2006-10-17 01:30:47 +0000 | [diff] [blame] | 480 | #else |
njn | f76d27a | 2009-05-28 01:53:07 +0000 | [diff] [blame] | 481 | # error "Unknown OS" |
sewardj | 1383bdd | 2006-10-17 01:30:47 +0000 | [diff] [blame] | 482 | #endif |
| 483 | |
njn | de62cbf | 2005-06-10 22:08:14 +0000 | [diff] [blame] | 484 | /*--------------------------------------------------------------------*/ |
| 485 | /*--- end ---*/ |
| 486 | /*--------------------------------------------------------------------*/ |