linux-user/signal.c

   1 /*
   2  *  Emulation of Linux signals
   3  *
   4  *  Copyright (c) 2003 Fabrice Bellard
   5  *
   6  *  This program is free software; you can redistribute it and/or modify
   7  *  it under the terms of the GNU General Public License as published by
   8  *  the Free Software Foundation; either version 2 of the License, or
   9  *  (at your option) any later version.
  10  *
  11  *  This program is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *  GNU General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU General Public License
  17  *  along with this program; if not, write to the Free Software
  18  *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  19  */
  20 #include <stdlib.h>
  21 #include <stdio.h>
  22 #include <string.h>
  23 #include <stdarg.h>
  24 #include <unistd.h>
  25 #include <signal.h>
  26 #include <errno.h>
  27 #include <sys/ucontext.h>
  28
  29 #ifdef __ia64__
  30 #undef uc_mcontext
  31 #undef uc_sigmask
  32 #undef uc_stack
  33 #undef uc_link
  34 #endif
  35
  36 #include "qemu.h"
  37
  38 //#define DEBUG_SIGNAL
  39
  40 #define MAX_SIGQUEUE_SIZE 1024
  41
  42 struct sigqueue {
  43     struct sigqueue *next;
  44     target_siginfo_t info;
  45 };
  46
  47 struct emulated_sigaction {
  48     struct target_sigaction sa;
  49     int pending; /* true if signal is pending */
  50     struct sigqueue *first;
  51     struct sigqueue info; /* in order to always have memory for the
  52                              first signal, we put it here */
  53 };
  54
  55 static struct emulated_sigaction sigact_table[TARGET_NSIG];
  56 static struct sigqueue sigqueue_table[MAX_SIGQUEUE_SIZE]; /* siginfo queue */
  57 static struct sigqueue *first_free; /* first free siginfo queue entry */
  58 static int signal_pending; /* non zero if a signal may be pending */
  59
  60 static void host_signal_handler(int host_signum, siginfo_t *info,
  61                                 void *puc);
  62
  63 /* XXX: do it properly */
  64 static inline int host_to_target_signal(int sig)
  65 {
  66     return sig;
  67 }
  68
  69 static inline int target_to_host_signal(int sig)
  70 {
  71     return sig;
  72 }
  73
  74 void host_to_target_sigset(target_sigset_t *d, sigset_t *s)
  75 {
  76     int i;
  77     for(i = 0;i < TARGET_NSIG_WORDS; i++) {
  78         d->sig[i] = tswapl(((unsigned long *)s)[i]);
  79     }
  80 }
  81
  82 void target_to_host_sigset(sigset_t *d, target_sigset_t *s)
  83 {
  84     int i;
  85     for(i = 0;i < TARGET_NSIG_WORDS; i++) {
  86         ((unsigned long *)d)[i] = tswapl(s->sig[i]);
  87     }
  88 }
  89
  90 void host_to_target_old_sigset(target_ulong *old_sigset,
  91                                const sigset_t *sigset)
  92 {
  93     *old_sigset = tswap32(*(unsigned long *)sigset & 0xffffffff);
  94 }
  95
  96 void target_to_host_old_sigset(sigset_t *sigset,
  97                                const target_ulong *old_sigset)
  98 {
  99     sigemptyset(sigset);
 100     *(unsigned long *)sigset = tswapl(*old_sigset);
 101 }
 102
 103 /* siginfo conversion */
 104
 105 static inline void host_to_target_siginfo_noswap(target_siginfo_t *tinfo,
 106                                                  const siginfo_t *info)
 107 {
 108     int sig;
 109     sig = host_to_target_signal(info->si_signo);
 110     tinfo->si_signo = sig;
 111     tinfo->si_errno = 0;
 112     tinfo->si_code = 0;
 113     if (sig == SIGILL || sig == SIGFPE || sig == SIGSEGV ||
 114         sig == SIGBUS || sig == SIGTRAP) {
 115         /* should never come here, but who knows. The information for
 116            the target is irrelevant */
 117         tinfo->_sifields._sigfault._addr = 0;
 118     } else if (sig >= TARGET_SIGRTMIN) {
 119         tinfo->_sifields._rt._pid = info->si_pid;
 120         tinfo->_sifields._rt._uid = info->si_uid;
 121         /* XXX: potential problem if 64 bit */
 122         tinfo->_sifields._rt._sigval.sival_ptr =
 123             (target_ulong)info->si_value.sival_ptr;
 124     }
 125 }
 126
 127 static void tswap_siginfo(target_siginfo_t *tinfo,
 128                           const target_siginfo_t *info)
 129 {
 130     int sig;
 131     sig = info->si_signo;
 132     tinfo->si_signo = tswap32(sig);
 133     tinfo->si_errno = tswap32(info->si_errno);
 134     tinfo->si_code = tswap32(info->si_code);
 135     if (sig == SIGILL || sig == SIGFPE || sig == SIGSEGV ||
 136         sig == SIGBUS || sig == SIGTRAP) {
 137         tinfo->_sifields._sigfault._addr =
 138             tswapl(info->_sifields._sigfault._addr);
 139     } else if (sig >= TARGET_SIGRTMIN) {
 140         tinfo->_sifields._rt._pid = tswap32(info->_sifields._rt._pid);
 141         tinfo->_sifields._rt._uid = tswap32(info->_sifields._rt._uid);
 142         tinfo->_sifields._rt._sigval.sival_ptr =
 143             tswapl(info->_sifields._rt._sigval.sival_ptr);
 144     }
 145 }
 146
 147
 148 void host_to_target_siginfo(target_siginfo_t *tinfo, const siginfo_t *info)
 149 {
 150     host_to_target_siginfo_noswap(tinfo, info);
 151     tswap_siginfo(tinfo, tinfo);
 152 }
 153
 154 /* XXX: we support only POSIX RT signals are used. */
 155 /* XXX: find a solution for 64 bit (additionnal malloced data is needed) */
 156 void target_to_host_siginfo(siginfo_t *info, const target_siginfo_t *tinfo)
 157 {
 158     info->si_signo = tswap32(tinfo->si_signo);
 159     info->si_errno = tswap32(tinfo->si_errno);
 160     info->si_code = tswap32(tinfo->si_code);
 161     info->si_pid = tswap32(tinfo->_sifields._rt._pid);
 162     info->si_uid = tswap32(tinfo->_sifields._rt._uid);
 163     info->si_value.sival_ptr =
 164         (void *)tswapl(tinfo->_sifields._rt._sigval.sival_ptr);
 165 }
 166
 167 void signal_init(void)
 168 {
 169     struct sigaction act;
 170     int i;
 171
 172     /* set all host signal handlers. ALL signals are blocked during
 173        the handlers to serialize them. */
 174     sigfillset(&act.sa_mask);
 175     act.sa_flags = SA_SIGINFO;
 176     act.sa_sigaction = host_signal_handler;
 177     for(i = 1; i < NSIG; i++) {
 178         sigaction(i, &act, NULL);
 179     }
 180
 181     memset(sigact_table, 0, sizeof(sigact_table));
 182
 183     first_free = &sigqueue_table[0];
 184     for(i = 0; i < MAX_SIGQUEUE_SIZE - 1; i++)
 185         sigqueue_table[i].next = &sigqueue_table[i + 1];
 186     sigqueue_table[MAX_SIGQUEUE_SIZE - 1].next = NULL;
 187 }
 188
 189 /* signal queue handling */
 190
 191 static inline struct sigqueue *alloc_sigqueue(void)
 192 {
 193     struct sigqueue *q = first_free;
 194     if (!q)
 195         return NULL;
 196     first_free = q->next;
 197     return q;
 198 }
 199
 200 static inline void free_sigqueue(struct sigqueue *q)
 201 {
 202     q->next = first_free;
 203     first_free = q;
 204 }
 205
 206 /* abort execution with signal */
 207 void __attribute((noreturn)) force_sig(int sig)
 208 {
 209     int host_sig;
 210     host_sig = target_to_host_signal(sig);
 211     fprintf(stderr, "qemu: uncaught target signal %d (%s) - exiting\n",
 212             sig, strsignal(host_sig));
 213 #if 1
 214     _exit(-host_sig);
 215 #else
 216     {
 217         struct sigaction act;
 218         sigemptyset(&act.sa_mask);
 219         act.sa_flags = SA_SIGINFO;
 220         act.sa_sigaction = SIG_DFL;
 221         sigaction(SIGABRT, &act, NULL);
 222         abort();
 223     }
 224 #endif
 225 }
 226
 227 /* queue a signal so that it will be send to the virtual CPU as soon
 228    as possible */
 229 int queue_signal(int sig, target_siginfo_t *info)
 230 {
 231     struct emulated_sigaction *k;
 232     struct sigqueue *q, **pq;
 233     target_ulong handler;
 234
 235 #if defined(DEBUG_SIGNAL)
 236     fprintf(stderr, "queue_signal: sig=%d\n",
 237             sig);
 238 #endif
 239     k = &sigact_table[sig - 1];
 240     handler = k->sa._sa_handler;
 241     if (handler == TARGET_SIG_DFL) {
 242         /* default handler : ignore some signal. The other are fatal */
 243         if (sig != TARGET_SIGCHLD &&
 244             sig != TARGET_SIGURG &&
 245             sig != TARGET_SIGWINCH) {
 246             force_sig(sig);
 247         } else {
 248             return 0; /* indicate ignored */
 249         }
 250     } else if (handler == TARGET_SIG_IGN) {
 251         /* ignore signal */
 252         return 0;
 253     } else if (handler == TARGET_SIG_ERR) {
 254         force_sig(sig);
 255     } else {
 256         pq = &k->first;
 257         if (sig < TARGET_SIGRTMIN) {
 258             /* if non real time signal, we queue exactly one signal */
 259             if (!k->pending)
 260                 q = &k->info;
 261             else
 262                 return 0;
 263         } else {
 264             if (!k->pending) {
 265                 /* first signal */
 266                 q = &k->info;
 267             } else {
 268                 q = alloc_sigqueue();
 269                 if (!q)
 270                     return -EAGAIN;
 271                 while (*pq != NULL)
 272                     pq = &(*pq)->next;
 273             }
 274         }
 275         *pq = q;
 276         q->info = *info;
 277         q->next = NULL;
 278         k->pending = 1;
 279         /* signal that a new signal is pending */
 280         signal_pending = 1;
 281         return 1; /* indicates that the signal was queued */
 282     }
 283 }
 284
 285 #if defined(DEBUG_SIGNAL)
 286 #ifdef __i386__
 287 static void dump_regs(struct ucontext *uc)
 288 {
 289     fprintf(stderr,
 290             "EAX=%08x EBX=%08x ECX=%08x EDX=%08x\n"
 291             "ESI=%08x EDI=%08x EBP=%08x ESP=%08x\n"
 292             "EFL=%08x EIP=%08x\n",
 293             uc->uc_mcontext.gregs[EAX],
 294             uc->uc_mcontext.gregs[EBX],
 295             uc->uc_mcontext.gregs[ECX],
 296             uc->uc_mcontext.gregs[EDX],
 297             uc->uc_mcontext.gregs[ESI],
 298             uc->uc_mcontext.gregs[EDI],
 299             uc->uc_mcontext.gregs[EBP],
 300             uc->uc_mcontext.gregs[ESP],
 301             uc->uc_mcontext.gregs[EFL],
 302             uc->uc_mcontext.gregs[EIP]);
 303 }
 304 #else
 305 static void dump_regs(struct ucontext *uc)
 306 {
 307 }
 308 #endif
 309
 310 #endif
 311
 312 static void host_signal_handler(int host_signum, siginfo_t *info,
 313                                 void *puc)
 314 {
 315     int sig;
 316     target_siginfo_t tinfo;
 317
 318     /* the CPU emulator uses some host signals to detect exceptions,
 319        we we forward to it some signals */
 320     if (host_signum == SIGSEGV || host_signum == SIGBUS) {
 321         if (cpu_x86_signal_handler(host_signum, info, puc))
 322             return;
 323     }
 324
 325     /* get target signal number */
 326     sig = host_to_target_signal(host_signum);
 327     if (sig < 1 || sig > TARGET_NSIG)
 328         return;
 329 #if defined(DEBUG_SIGNAL)
 330     fprintf(stderr, "qemu: got signal %d\n", sig);
 331     dump_regs(puc);
 332 #endif
 333     host_to_target_siginfo_noswap(&tinfo, info);
 334     if (queue_signal(sig, &tinfo) == 1) {
 335         /* interrupt the virtual CPU as soon as possible */
 336         cpu_x86_interrupt(global_env);
 337     }
 338 }
 339
 340 int do_sigaction(int sig, const struct target_sigaction *act,
 341                  struct target_sigaction *oact)
 342 {
 343     struct emulated_sigaction *k;
 344
 345     if (sig < 1 || sig > TARGET_NSIG)
 346         return -EINVAL;
 347     k = &sigact_table[sig - 1];
 348 #if defined(DEBUG_SIGNAL) && 0
 349     fprintf(stderr, "sigaction sig=%d act=0x%08x, oact=0x%08x\n",
 350             sig, (int)act, (int)oact);
 351 #endif
 352     if (oact) {
 353         oact->_sa_handler = tswapl(k->sa._sa_handler);
 354         oact->sa_flags = tswapl(k->sa.sa_flags);
 355         oact->sa_restorer = tswapl(k->sa.sa_restorer);
 356         oact->sa_mask = k->sa.sa_mask;
 357     }
 358     if (act) {
 359         k->sa._sa_handler = tswapl(act->_sa_handler);
 360         k->sa.sa_flags = tswapl(act->sa_flags);
 361         k->sa.sa_restorer = tswapl(act->sa_restorer);
 362         k->sa.sa_mask = act->sa_mask;
 363     }
 364     return 0;
 365 }
 366
 367 #ifdef TARGET_I386
 368
 369 /* from the Linux kernel */
 370
 371 struct target_fpreg {
 372         uint16_t significand[4];
 373         uint16_t exponent;
 374 };
 375
 376 struct target_fpxreg {
 377         uint16_t significand[4];
 378         uint16_t exponent;
 379         uint16_t padding[3];
 380 };
 381
 382 struct target_xmmreg {
 383         target_ulong element[4];
 384 };
 385
 386 struct target_fpstate {
 387         /* Regular FPU environment */
 388         target_ulong    cw;
 389         target_ulong    sw;
 390         target_ulong    tag;
 391         target_ulong    ipoff;
 392         target_ulong    cssel;
 393         target_ulong    dataoff;
 394         target_ulong    datasel;
 395         struct target_fpreg     _st[8];
 396         uint16_t        status;
 397         uint16_t        magic;          /* 0xffff = regular FPU data only */
 398
 399         /* FXSR FPU environment */
 400         target_ulong    _fxsr_env[6];   /* FXSR FPU env is ignored */
 401         target_ulong    mxcsr;
 402         target_ulong    reserved;
 403         struct target_fpxreg    _fxsr_st[8];    /* FXSR FPU reg data is ignored */
 404         struct target_xmmreg    _xmm[8];
 405         target_ulong    padding[56];
 406 };
 407
 408 #define X86_FXSR_MAGIC          0x0000
 409
 410 struct target_sigcontext {
 411         uint16_t gs, __gsh;
 412         uint16_t fs, __fsh;
 413         uint16_t es, __esh;
 414         uint16_t ds, __dsh;
 415         target_ulong edi;
 416         target_ulong esi;
 417         target_ulong ebp;
 418         target_ulong esp;
 419         target_ulong ebx;
 420         target_ulong edx;
 421         target_ulong ecx;
 422         target_ulong eax;
 423         target_ulong trapno;
 424         target_ulong err;
 425         target_ulong eip;
 426         uint16_t cs, __csh;
 427         target_ulong eflags;
 428         target_ulong esp_at_signal;
 429         uint16_t ss, __ssh;
 430         target_ulong fpstate; /* pointer */
 431         target_ulong oldmask;
 432         target_ulong cr2;
 433 };
 434
 435 typedef struct target_sigaltstack {
 436         target_ulong ss_sp;
 437         int ss_flags;
 438         target_ulong ss_size;
 439 } target_stack_t;
 440
 441 struct target_ucontext {
 442         target_ulong      uc_flags;
 443         target_ulong      uc_link;
 444         target_stack_t    uc_stack;
 445         struct target_sigcontext uc_mcontext;
 446         target_sigset_t   uc_sigmask;   /* mask last for extensibility */
 447 };
 448
 449 struct sigframe
 450 {
 451     target_ulong pretcode;
 452     int sig;
 453     struct target_sigcontext sc;
 454     struct target_fpstate fpstate;
 455     target_ulong extramask[TARGET_NSIG_WORDS-1];
 456     char retcode[8];
 457 };
 458
 459 struct rt_sigframe
 460 {
 461     target_ulong pretcode;
 462     int sig;
 463     target_ulong pinfo;
 464     target_ulong puc;
 465     struct target_siginfo info;
 466     struct target_ucontext uc;
 467     struct target_fpstate fpstate;
 468     char retcode[8];
 469 };
 470
 471 /*
 472  * Set up a signal frame.
 473  */
 474
 475 #define __put_user(x,ptr)\
 476 ({\
 477     int size = sizeof(*ptr);\
 478     switch(size) {\
 479     case 1:\
 480         stb(ptr, (typeof(*ptr))(x));\
 481         break;\
 482     case 2:\
 483         stw(ptr, (typeof(*ptr))(x));\
 484         break;\
 485     case 4:\
 486         stl(ptr, (typeof(*ptr))(x));\
 487         break;\
 488     case 8:\
 489         stq(ptr, (typeof(*ptr))(x));\
 490         break;\
 491     default:\
 492         abort();\
 493     }\
 494     0;\
 495 })
 496
 497 #define get_user(val, ptr) (typeof(*ptr))(*(ptr))
 498
 499
 500 #define __copy_to_user(dst, src, size)\
 501 ({\
 502     memcpy(dst, src, size);\
 503     0;\
 504 })
 505
 506 static inline int copy_siginfo_to_user(target_siginfo_t *tinfo,
 507                                        const target_siginfo_t *info)
 508 {
 509     tswap_siginfo(tinfo, info);
 510     return 0;
 511 }
 512
 513 /* XXX: save x87 state */
 514 static int
 515 setup_sigcontext(struct target_sigcontext *sc, struct target_fpstate *fpstate,
 516                  CPUX86State *env, unsigned long mask)
 517 {
 518         int err = 0;
 519
 520         err |= __put_user(env->segs[R_GS], (unsigned int *)&sc->gs);
 521         err |= __put_user(env->segs[R_FS], (unsigned int *)&sc->fs);
 522         err |= __put_user(env->segs[R_ES], (unsigned int *)&sc->es);
 523         err |= __put_user(env->segs[R_DS], (unsigned int *)&sc->ds);
 524         err |= __put_user(env->regs[R_EDI], &sc->edi);
 525         err |= __put_user(env->regs[R_ESI], &sc->esi);
 526         err |= __put_user(env->regs[R_EBP], &sc->ebp);
 527         err |= __put_user(env->regs[R_ESP], &sc->esp);
 528         err |= __put_user(env->regs[R_EBX], &sc->ebx);
 529         err |= __put_user(env->regs[R_EDX], &sc->edx);
 530         err |= __put_user(env->regs[R_ECX], &sc->ecx);
 531         err |= __put_user(env->regs[R_EAX], &sc->eax);
 532         err |= __put_user(env->exception_index, &sc->trapno);
 533         err |= __put_user(env->error_code, &sc->err);
 534         err |= __put_user(env->eip, &sc->eip);
 535         err |= __put_user(env->segs[R_CS], (unsigned int *)&sc->cs);
 536         err |= __put_user(env->eflags, &sc->eflags);
 537         err |= __put_user(env->regs[R_ESP], &sc->esp_at_signal);
 538         err |= __put_user(env->segs[R_SS], (unsigned int *)&sc->ss);
 539 #if 0
 540         tmp = save_i387(fpstate);
 541         if (tmp < 0)
 542           err = 1;
 543         else
 544           err |= __put_user(tmp ? fpstate : NULL, &sc->fpstate);
 545 #else
 546         err |= __put_user(0, &sc->fpstate);
 547 #endif
 548         /* non-iBCS2 extensions.. */
 549         err |= __put_user(mask, &sc->oldmask);
 550         err |= __put_user(/*current->thread.cr2*/ 0, &sc->cr2);
 551         return err;
 552 }
 553
 554 /*
 555  * Determine which stack to use..
 556  */
 557
 558 static inline void *
 559 get_sigframe(struct emulated_sigaction *ka, CPUX86State *env, size_t frame_size)
 560 {
 561         unsigned long esp;
 562
 563         /* Default to using normal stack */
 564         esp = env->regs[R_ESP];
 565 #if 0
 566         /* This is the X/Open sanctioned signal stack switching.  */
 567         if (ka->sa.sa_flags & SA_ONSTACK) {
 568                 if (sas_ss_flags(esp) == 0)
 569                         esp = current->sas_ss_sp + current->sas_ss_size;
 570         }
 571
 572         /* This is the legacy signal stack switching. */
 573         else if ((regs->xss & 0xffff) != __USER_DS &&
 574                  !(ka->sa.sa_flags & SA_RESTORER) &&
 575                  ka->sa.sa_restorer) {
 576                 esp = (unsigned long) ka->sa.sa_restorer;
 577         }
 578 #endif
 579         return (void *)((esp - frame_size) & -8ul);
 580 }
 581
 582 static void setup_frame(int sig, struct emulated_sigaction *ka,
 583                         target_sigset_t *set, CPUX86State *env)
 584 {
 585         struct sigframe *frame;
 586         int err = 0;
 587
 588         frame = get_sigframe(ka, env, sizeof(*frame));
 589
 590 #if 0
 591         if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
 592                 goto give_sigsegv;
 593 #endif
 594         err |= __put_user((/*current->exec_domain
 595                            && current->exec_domain->signal_invmap
 596                            && sig < 32
 597                            ? current->exec_domain->signal_invmap[sig]
 598                            : */ sig),
 599                           &frame->sig);
 600         if (err)
 601                 goto give_sigsegv;
 602
 603         setup_sigcontext(&frame->sc, &frame->fpstate, env, set->sig[0]);
 604         if (err)
 605                 goto give_sigsegv;
 606
 607         if (TARGET_NSIG_WORDS > 1) {
 608                 err |= __copy_to_user(frame->extramask, &set->sig[1],
 609                                       sizeof(frame->extramask));
 610         }
 611         if (err)
 612                 goto give_sigsegv;
 613
 614         /* Set up to return from userspace.  If provided, use a stub
 615            already in userspace.  */
 616         if (ka->sa.sa_flags & TARGET_SA_RESTORER) {
 617                 err |= __put_user(ka->sa.sa_restorer, &frame->pretcode);
 618         } else {
 619                 err |= __put_user(frame->retcode, &frame->pretcode);
 620                 /* This is popl %eax ; movl $,%eax ; int $0x80 */
 621                 err |= __put_user(0xb858, (short *)(frame->retcode+0));
 622                 err |= __put_user(TARGET_NR_sigreturn, (int *)(frame->retcode+2));
 623                 err |= __put_user(0x80cd, (short *)(frame->retcode+6));
 624         }
 625
 626         if (err)
 627                 goto give_sigsegv;
 628
 629         /* Set up registers for signal handler */
 630         env->regs[R_ESP] = (unsigned long) frame;
 631         env->eip = (unsigned long) ka->sa._sa_handler;
 632
 633         cpu_x86_load_seg(env, R_DS, __USER_DS);
 634         cpu_x86_load_seg(env, R_ES, __USER_DS);
 635         cpu_x86_load_seg(env, R_SS, __USER_DS);
 636         cpu_x86_load_seg(env, R_CS, __USER_CS);
 637         env->eflags &= ~TF_MASK;
 638
 639         return;
 640
 641 give_sigsegv:
 642         if (sig == TARGET_SIGSEGV)
 643                 ka->sa._sa_handler = TARGET_SIG_DFL;
 644         force_sig(TARGET_SIGSEGV /* , current */);
 645 }
 646
 647 static void setup_rt_frame(int sig, struct emulated_sigaction *ka,
 648                            target_siginfo_t *info,
 649                            target_sigset_t *set, CPUX86State *env)
 650 {
 651         struct rt_sigframe *frame;
 652         int err = 0;
 653
 654         frame = get_sigframe(ka, env, sizeof(*frame));
 655
 656 #if 0
 657         if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
 658                 goto give_sigsegv;
 659 #endif
 660
 661         err |= __put_user((/*current->exec_domain
 662                            && current->exec_domain->signal_invmap
 663                            && sig < 32
 664                            ? current->exec_domain->signal_invmap[sig]
 665                            : */sig),
 666                           &frame->sig);
 667         err |= __put_user((target_ulong)&frame->info, &frame->pinfo);
 668         err |= __put_user((target_ulong)&frame->uc, &frame->puc);
 669         err |= copy_siginfo_to_user(&frame->info, info);
 670         if (err)
 671                 goto give_sigsegv;
 672
 673         /* Create the ucontext.  */
 674         err |= __put_user(0, &frame->uc.uc_flags);
 675         err |= __put_user(0, &frame->uc.uc_link);
 676         err |= __put_user(/*current->sas_ss_sp*/ 0, &frame->uc.uc_stack.ss_sp);
 677         err |= __put_user(/* sas_ss_flags(regs->esp) */ 0,
 678                           &frame->uc.uc_stack.ss_flags);
 679         err |= __put_user(/* current->sas_ss_size */ 0, &frame->uc.uc_stack.ss_size);
 680         err |= setup_sigcontext(&frame->uc.uc_mcontext, &frame->fpstate,
 681                                 env, set->sig[0]);
 682         err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
 683         if (err)
 684                 goto give_sigsegv;
 685
 686         /* Set up to return from userspace.  If provided, use a stub
 687            already in userspace.  */
 688         if (ka->sa.sa_flags & TARGET_SA_RESTORER) {
 689                 err |= __put_user(ka->sa.sa_restorer, &frame->pretcode);
 690         } else {
 691                 err |= __put_user(frame->retcode, &frame->pretcode);
 692                 /* This is movl $,%eax ; int $0x80 */
 693                 err |= __put_user(0xb8, (char *)(frame->retcode+0));
 694                 err |= __put_user(TARGET_NR_rt_sigreturn, (int *)(frame->retcode+1));
 695                 err |= __put_user(0x80cd, (short *)(frame->retcode+5));
 696         }
 697
 698         if (err)
 699                 goto give_sigsegv;
 700
 701         /* Set up registers for signal handler */
 702         env->regs[R_ESP] = (unsigned long) frame;
 703         env->eip = (unsigned long) ka->sa._sa_handler;
 704
 705         cpu_x86_load_seg(env, R_DS, __USER_DS);
 706         cpu_x86_load_seg(env, R_ES, __USER_DS);
 707         cpu_x86_load_seg(env, R_SS, __USER_DS);
 708         cpu_x86_load_seg(env, R_CS, __USER_CS);
 709         env->eflags &= ~TF_MASK;
 710
 711         return;
 712
 713 give_sigsegv:
 714         if (sig == TARGET_SIGSEGV)
 715                 ka->sa._sa_handler = TARGET_SIG_DFL;
 716         force_sig(TARGET_SIGSEGV /* , current */);
 717 }
 718
 719 static int
 720 restore_sigcontext(CPUX86State *env, struct target_sigcontext *sc, int *peax)
 721 {
 722         unsigned int err = 0;
 723
 724
 725
 726 #define COPY(x)         err |= __get_user(regs->x, &sc->x)
 727
 728 #define COPY_SEG(seg)                                                   \
 729         { unsigned short tmp;                                           \
 730           err |= __get_user(tmp, &sc->seg);                             \
 731           regs->x##seg = tmp; }
 732
 733 #define COPY_SEG_STRICT(seg)                                            \
 734         { unsigned short tmp;                                           \
 735           err |= __get_user(tmp, &sc->seg);                             \
 736           regs->x##seg = tmp|3; }
 737
 738 #define GET_SEG(seg)                                                    \
 739         { unsigned short tmp;                                           \
 740           err |= __get_user(tmp, &sc->seg);                             \
 741           loadsegment(seg,tmp); }
 742
 743         cpu_x86_load_seg(env, R_GS, lduw(&sc->gs));
 744         cpu_x86_load_seg(env, R_FS, lduw(&sc->fs));
 745         cpu_x86_load_seg(env, R_ES, lduw(&sc->es));
 746         cpu_x86_load_seg(env, R_DS, lduw(&sc->ds));
 747
 748         env->regs[R_EDI] = ldl(&sc->edi);
 749         env->regs[R_ESI] = ldl(&sc->esi);
 750         env->regs[R_EBP] = ldl(&sc->ebp);
 751         env->regs[R_ESP] = ldl(&sc->esp);
 752         env->regs[R_EBX] = ldl(&sc->ebx);
 753         env->regs[R_EDX] = ldl(&sc->edx);
 754         env->regs[R_ECX] = ldl(&sc->ecx);
 755         env->eip = ldl(&sc->eip);
 756
 757         cpu_x86_load_seg(env, R_CS, lduw(&sc->cs) | 3);
 758         cpu_x86_load_seg(env, R_SS, lduw(&sc->ss) | 3);
 759
 760         {
 761                 unsigned int tmpflags;
 762                 tmpflags = ldl(&sc->eflags);
 763                 env->eflags = (env->eflags & ~0x40DD5) | (tmpflags & 0x40DD5);
 764                 //              regs->orig_eax = -1;            /* disable syscall checks */
 765         }
 766
 767 #if 0
 768         {
 769                 struct _fpstate * buf;
 770                 err |= __get_user(buf, &sc->fpstate);
 771                 if (buf) {
 772                         if (verify_area(VERIFY_READ, buf, sizeof(*buf)))
 773                                 goto badframe;
 774                         err |= restore_i387(buf);
 775                 }
 776         }
 777 #endif
 778         *peax = ldl(&sc->eax);
 779         return err;
 780 #if 0
 781 badframe:
 782         return 1;
 783 #endif
 784 }
 785
 786 long do_sigreturn(CPUX86State *env)
 787 {
 788     struct sigframe *frame = (struct sigframe *)(env->regs[R_ESP] - 8);
 789     target_sigset_t target_set;
 790     sigset_t set;
 791     int eax, i;
 792
 793 #if defined(DEBUG_SIGNAL)
 794     fprintf(stderr, "do_sigreturn\n");
 795 #endif
 796     /* set blocked signals */
 797     target_set.sig[0] = frame->sc.oldmask;
 798     for(i = 1; i < TARGET_NSIG_WORDS; i++)
 799         target_set.sig[i] = frame->extramask[i - 1];
 800
 801     target_to_host_sigset(&set, &target_set);
 802     sigprocmask(SIG_SETMASK, &set, NULL);
 803
 804     /* restore registers */
 805     if (restore_sigcontext(env, &frame->sc, &eax))
 806         goto badframe;
 807     return eax;
 808
 809 badframe:
 810     force_sig(TARGET_SIGSEGV);
 811     return 0;
 812 }
 813
 814 long do_rt_sigreturn(CPUX86State *env)
 815 {
 816         struct rt_sigframe *frame = (struct rt_sigframe *)(env->regs[R_ESP] - 4);
 817         target_sigset_t target_set;
 818         sigset_t set;
 819         //      stack_t st;
 820         int eax;
 821
 822 #if 0
 823         if (verify_area(VERIFY_READ, frame, sizeof(*frame)))
 824                 goto badframe;
 825 #endif
 826         memcpy(&target_set, &frame->uc.uc_sigmask, sizeof(target_sigset_t));
 827
 828         target_to_host_sigset(&set, &target_set);
 829         sigprocmask(SIG_SETMASK, &set, NULL);
 830
 831         if (restore_sigcontext(env, &frame->uc.uc_mcontext, &eax))
 832                 goto badframe;
 833
 834 #if 0
 835         if (__copy_from_user(&st, &frame->uc.uc_stack, sizeof(st)))
 836                 goto badframe;
 837         /* It is more difficult to avoid calling this function than to
 838            call it and ignore errors.  */
 839         do_sigaltstack(&st, NULL, regs->esp);
 840 #endif
 841         return eax;
 842
 843 badframe:
 844         force_sig(TARGET_SIGSEGV);
 845         return 0;
 846 }
 847
 848 #endif
 849
 850 void process_pending_signals(void *cpu_env)
 851 {
 852     int sig;
 853     target_ulong handler;
 854     sigset_t set, old_set;
 855     target_sigset_t target_old_set;
 856     struct emulated_sigaction *k;
 857     struct sigqueue *q;
 858
 859     if (!signal_pending)
 860         return;
 861
 862     k = sigact_table;
 863     for(sig = 1; sig <= TARGET_NSIG; sig++) {
 864         if (k->pending)
 865             goto handle_signal;
 866         k++;
 867     }
 868     /* if no signal is pending, just return */
 869     signal_pending = 0;
 870     return;
 871
 872  handle_signal:
 873 #ifdef DEBUG_SIGNAL
 874     fprintf(stderr, "qemu: process signal %d\n", sig);
 875 #endif
 876     /* dequeue signal */
 877     q = k->first;
 878     k->first = q->next;
 879     if (!k->first)
 880         k->pending = 0;
 881
 882     handler = k->sa._sa_handler;
 883     if (handler == TARGET_SIG_DFL) {
 884         /* default handler : ignore some signal. The other are fatal */
 885         if (sig != TARGET_SIGCHLD &&
 886             sig != TARGET_SIGURG &&
 887             sig != TARGET_SIGWINCH) {
 888             force_sig(sig);
 889         }
 890     } else if (handler == TARGET_SIG_IGN) {
 891         /* ignore sig */
 892     } else if (handler == TARGET_SIG_ERR) {
 893         force_sig(sig);
 894     } else {
 895         /* compute the blocked signals during the handler execution */
 896         target_to_host_sigset(&set, &k->sa.sa_mask);
 897         /* SA_NODEFER indicates that the current signal should not be
 898            blocked during the handler */
 899         if (!(k->sa.sa_flags & TARGET_SA_NODEFER))
 900             sigaddset(&set, target_to_host_signal(sig));
 901
 902         /* block signals in the handler using Linux */
 903         sigprocmask(SIG_BLOCK, &set, &old_set);
 904         /* save the previous blocked signal state to restore it at the
 905            end of the signal execution (see do_sigreturn) */
 906         host_to_target_sigset(&target_old_set, &old_set);
 907
 908         /* if the CPU is in VM86 mode, we restore the 32 bit values */
 909 #ifdef TARGET_I386
 910         {
 911             CPUX86State *env = cpu_env;
 912             if (env->eflags & VM_MASK)
 913                 save_v86_state(env);
 914         }
 915 #endif
 916         /* prepare the stack frame of the virtual CPU */
 917         if (k->sa.sa_flags & TARGET_SA_SIGINFO)
 918             setup_rt_frame(sig, k, &q->info, &target_old_set, cpu_env);
 919         else
 920             setup_frame(sig, k, &target_old_set, cpu_env);
 921         if (k->sa.sa_flags & TARGET_SA_RESETHAND)
 922             k->sa._sa_handler = TARGET_SIG_DFL;
 923     }
 924     if (q != &k->info)
 925         free_sigqueue(q);
 926 }
 927
 928