+++ /dev/null
-/*
- * Emulation of Linux signals
- *
- * Copyright (c) 2003 Fabrice Bellard
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, see <http://www.gnu.org/licenses/>.
- */
-#include <stdlib.h>
-#include <stdio.h>
-#include <string.h>
-#include <stdarg.h>
-#include <unistd.h>
-#include <errno.h>
-#include <sys/ucontext.h>
-
-#ifdef __ia64__
-#undef uc_mcontext
-#undef uc_sigmask
-#undef uc_stack
-#undef uc_link
-#endif
-
-#include "qemu.h"
-#include "qemu-common.h"
-
-#define DEBUG_SIGNAL
-
-#define MAX_SIGQUEUE_SIZE 1024
-
-struct sigqueue {
- struct sigqueue *next;
- target_siginfo_t info;
-};
-
-struct emulated_sigaction {
- struct target_sigaction sa;
- int pending; /* true if signal is pending */
- struct sigqueue *first;
- struct sigqueue info; /* in order to always have memory for the
- first signal, we put it here */
-};
-
-static struct sigaltstack target_sigaltstack_used = {
- 0, 0, SA_DISABLE
-};
-
-static struct emulated_sigaction sigact_table[NSIG];
-static struct sigqueue sigqueue_table[MAX_SIGQUEUE_SIZE]; /* siginfo queue */
-static struct sigqueue *first_free; /* first free siginfo queue entry */
-static int signal_pending; /* non zero if a signal may be pending */
-
-static void host_signal_handler(int host_signum, siginfo_t *info,
- void *puc);
-
-
-static inline int host_to_target_signal(int sig)
-{
- return sig;
-}
-
-static inline int target_to_host_signal(int sig)
-{
- return sig;
-}
-
-/* siginfo conversion */
-
-
-
-void host_to_target_siginfo(target_siginfo_t *tinfo, const siginfo_t *info)
-{
-
-}
-
-void target_to_host_siginfo(siginfo_t *info, const target_siginfo_t *tinfo)
-{
-
-}
-
-void signal_init(void)
-{
- struct sigaction act;
- int i;
-
- /* set all host signal handlers. ALL signals are blocked during
- the handlers to serialize them. */
- sigfillset(&act.sa_mask);
- act.sa_flags = SA_SIGINFO;
- act.sa_sigaction = host_signal_handler;
- for(i = 1; i < NSIG; i++) {
- sigaction(i, &act, NULL);
- }
-
- memset(sigact_table, 0, sizeof(sigact_table));
-
- first_free = &sigqueue_table[0];
- for(i = 0; i < MAX_SIGQUEUE_SIZE - 1; i++)
- sigqueue_table[i].next = &sigqueue_table[i + 1];
- sigqueue_table[MAX_SIGQUEUE_SIZE - 1].next = NULL;
-}
-
-/* signal queue handling */
-
-static inline struct sigqueue *alloc_sigqueue(void)
-{
- struct sigqueue *q = first_free;
- if (!q)
- return NULL;
- first_free = q->next;
- return q;
-}
-
-static inline void free_sigqueue(struct sigqueue *q)
-{
- q->next = first_free;
- first_free = q;
-}
-
-/* abort execution with signal */
-void QEMU_NORETURN force_sig(int sig)
-{
- int host_sig;
- host_sig = target_to_host_signal(sig);
- fprintf(stderr, "qemu: uncaught target signal %d (%s) - exiting\n",
- sig, strsignal(host_sig));
- _exit(-host_sig);
-}
-
-/* queue a signal so that it will be send to the virtual CPU as soon
- as possible */
-int queue_signal(int sig, target_siginfo_t *info)
-{
- struct emulated_sigaction *k;
- struct sigqueue *q, **pq;
- target_ulong handler;
-
-#if defined(DEBUG_SIGNAL)
- fprintf(stderr, "queue_signal: sig=%d\n",
- sig);
-#endif
- k = &sigact_table[sig - 1];
- handler = (target_ulong)k->sa.sa_handler;
- if (handler == SIG_DFL) {
- /* default handler : ignore some signal. The other are fatal */
- if (sig != SIGCHLD &&
- sig != SIGURG &&
- sig != SIGWINCH) {
- force_sig(sig);
- } else {
- return 0; /* indicate ignored */
- }
- } else if (handler == host_to_target_signal(SIG_IGN)) {
- /* ignore signal */
- return 0;
- } else if (handler == host_to_target_signal(SIG_ERR)) {
- force_sig(sig);
- } else {
- pq = &k->first;
- if (!k->pending) {
- /* first signal */
- q = &k->info;
- } else {
- q = alloc_sigqueue();
- if (!q)
- return -EAGAIN;
- while (*pq != NULL)
- pq = &(*pq)->next;
- }
- *pq = q;
- q->info = *info;
- q->next = NULL;
- k->pending = 1;
- /* signal that a new signal is pending */
- signal_pending = 1;
- return 1; /* indicates that the signal was queued */
- }
-}
-
-static void host_signal_handler(int host_signum, siginfo_t *info,
- void *puc)
-{
- int sig;
- target_siginfo_t tinfo;
-
- /* the CPU emulator uses some host signals to detect exceptions,
- we we forward to it some signals */
- if (host_signum == SIGSEGV || host_signum == SIGBUS) {
- if (cpu_signal_handler(host_signum, (void*)info, puc))
- return;
- }
-
- /* get target signal number */
- sig = host_to_target_signal(host_signum);
- if (sig < 1 || sig > NSIG)
- return;
-
-#if defined(DEBUG_SIGNAL)
- fprintf(stderr, "qemu: got signal %d\n", sig);
-#endif
- if (queue_signal(sig, &tinfo) == 1) {
- /* interrupt the virtual CPU as soon as possible */
- cpu_exit(global_env);
- }
-}
-
-int do_sigaltstack(const struct sigaltstack *ss, struct sigaltstack *oss)
-{
- /* XXX: test errors */
- if(oss)
- {
- oss->ss_sp = tswap32(target_sigaltstack_used.ss_sp);
- oss->ss_size = tswap32(target_sigaltstack_used.ss_size);
- oss->ss_flags = tswap32(target_sigaltstack_used.ss_flags);
- }
- if(ss)
- {
- target_sigaltstack_used.ss_sp = tswap32(ss->ss_sp);
- target_sigaltstack_used.ss_size = tswap32(ss->ss_size);
- target_sigaltstack_used.ss_flags = tswap32(ss->ss_flags);
- }
- return 0;
-}
-
-int do_sigaction(int sig, const struct sigaction *act,
- struct sigaction *oact)
-{
- struct emulated_sigaction *k;
- struct sigaction act1;
- int host_sig;
-
- if (sig < 1 || sig > NSIG)
- return -EINVAL;
-
- k = &sigact_table[sig - 1];
-#if defined(DEBUG_SIGNAL)
- fprintf(stderr, "sigaction 1 sig=%d act=0x%08x, oact=0x%08x\n",
- sig, (int)act, (int)oact);
-#endif
- if (oact) {
-#if defined(DEBUG_SIGNAL)
- fprintf(stderr, "sigaction 1 sig=%d act=0x%08x, oact=0x%08x\n",
- sig, (int)act, (int)oact);
-#endif
-
- oact->sa_handler = tswapl(k->sa.sa_handler);
- oact->sa_flags = tswapl(k->sa.sa_flags);
- oact->sa_mask = tswapl(k->sa.sa_mask);
- }
- if (act) {
-#if defined(DEBUG_SIGNAL)
- fprintf(stderr, "sigaction handler 0x%x flag 0x%x mask 0x%x\n",
- act->sa_handler, act->sa_flags, act->sa_mask);
-#endif
-
- k->sa.sa_handler = tswapl(act->sa_handler);
- k->sa.sa_flags = tswapl(act->sa_flags);
- k->sa.sa_mask = tswapl(act->sa_mask);
- /* we update the host signal state */
- host_sig = target_to_host_signal(sig);
- if (host_sig != SIGSEGV && host_sig != SIGBUS) {
-#if defined(DEBUG_SIGNAL)
- fprintf(stderr, "sigaction handler going to call sigaction\n");
-#endif
-
- sigfillset(&act1.sa_mask);
- act1.sa_flags = SA_SIGINFO;
- if (k->sa.sa_flags & SA_RESTART)
- act1.sa_flags |= SA_RESTART;
- /* NOTE: it is important to update the host kernel signal
- ignore state to avoid getting unexpected interrupted
- syscalls */
- if (k->sa.sa_handler == SIG_IGN) {
- act1.sa_sigaction = (void *)SIG_IGN;
- } else if (k->sa.sa_handler == SIG_DFL) {
- act1.sa_sigaction = (void *)SIG_DFL;
- } else {
- act1.sa_sigaction = host_signal_handler;
- }
- sigaction(host_sig, &act1, NULL);
- }
- }
- return 0;
-}
-
-
-#ifdef TARGET_I386
-
-static inline void *
-get_sigframe(struct emulated_sigaction *ka, CPUX86State *env, size_t frame_size)
-{
- /* XXX Fix that */
- if(target_sigaltstack_used.ss_flags & SA_DISABLE)
- {
- int esp;
- /* Default to using normal stack */
- esp = env->regs[R_ESP];
-
- return (void *)((esp - frame_size) & -8ul);
- }
- else
- {
- return target_sigaltstack_used.ss_sp;
- }
-}
-
-static void setup_frame(int sig, struct emulated_sigaction *ka,
- void *set, CPUX86State *env)
-{
- void *frame;
-
- fprintf(stderr, "setup_frame %d\n", sig);
- frame = get_sigframe(ka, env, sizeof(*frame));
-
- /* Set up registers for signal handler */
- env->regs[R_ESP] = (unsigned long) frame;
- env->eip = (unsigned long) ka->sa.sa_handler;
-
- env->eflags &= ~TF_MASK;
-
- return;
-
-give_sigsegv:
- if (sig == SIGSEGV)
- ka->sa.sa_handler = SIG_DFL;
- force_sig(SIGSEGV /* , current */);
-}
-
-long do_sigreturn(CPUX86State *env, int num)
-{
- int i = 0;
- struct target_sigcontext *scp = get_int_arg(&i, env);
- /* XXX Get current signal number */
- /* XXX Adjust accordin to sc_onstack, sc_mask */
- if(tswapl(scp->sc_onstack) & 0x1)
- target_sigaltstack_used.ss_flags |= ~SA_DISABLE;
- else
- target_sigaltstack_used.ss_flags &= SA_DISABLE;
- int set = tswapl(scp->sc_eax);
- sigprocmask(SIG_SETMASK, &set, NULL);
-
- fprintf(stderr, "do_sigreturn: partially implemented %x EAX:%x EBX:%x\n", scp->sc_mask, tswapl(scp->sc_eax), tswapl(scp->sc_ebx));
- fprintf(stderr, "ECX:%x EDX:%x EDI:%x\n", scp->sc_ecx, tswapl(scp->sc_edx), tswapl(scp->sc_edi));
- fprintf(stderr, "EIP:%x\n", tswapl(scp->sc_eip));
-
- env->regs[R_EAX] = tswapl(scp->sc_eax);
- env->regs[R_EBX] = tswapl(scp->sc_ebx);
- env->regs[R_ECX] = tswapl(scp->sc_ecx);
- env->regs[R_EDX] = tswapl(scp->sc_edx);
- env->regs[R_EDI] = tswapl(scp->sc_edi);
- env->regs[R_ESI] = tswapl(scp->sc_esi);
- env->regs[R_EBP] = tswapl(scp->sc_ebp);
- env->regs[R_ESP] = tswapl(scp->sc_esp);
- env->segs[R_SS].selector = (void*)tswapl(scp->sc_ss);
- env->eflags = tswapl(scp->sc_eflags);
- env->eip = tswapl(scp->sc_eip);
- env->segs[R_CS].selector = (void*)tswapl(scp->sc_cs);
- env->segs[R_DS].selector = (void*)tswapl(scp->sc_ds);
- env->segs[R_ES].selector = (void*)tswapl(scp->sc_es);
- env->segs[R_FS].selector = (void*)tswapl(scp->sc_fs);
- env->segs[R_GS].selector = (void*)tswapl(scp->sc_gs);
-
- /* Again, because our caller's caller will reset EAX */
- return env->regs[R_EAX];
-}
-
-#else
-
-static void setup_frame(int sig, struct emulated_sigaction *ka,
- void *set, CPUArchState *env)
-{
- fprintf(stderr, "setup_frame: not implemented\n");
-}
-
-long do_sigreturn(CPUArchState *env, int num)
-{
- int i = 0;
- struct target_sigcontext *scp = get_int_arg(&i, env);
- fprintf(stderr, "do_sigreturn: not implemented\n");
- return -ENOSYS;
-}
-
-#endif
-
-void process_pending_signals(void *cpu_env)
-{
- struct emulated_sigaction *k;
- struct sigqueue *q;
- target_ulong handler;
- int sig;
-
- if (!signal_pending)
- return;
-
- k = sigact_table;
-
- for(sig = 1; sig <= NSIG; sig++) {
- if (k->pending)
- goto handle_signal;
- k++;
- }
-
- /* if no signal is pending, just return */
- signal_pending = 0;
- return;
-handle_signal:
- #ifdef DEBUG_SIGNAL
- fprintf(stderr, "qemu: process signal %d\n", sig);
- #endif
- /* dequeue signal */
- q = k->first;
- k->first = q->next;
- if (!k->first)
- k->pending = 0;
-
- sig = gdb_handlesig (cpu_env, sig);
- if (!sig) {
- fprintf (stderr, "Lost signal\n");
- abort();
- }
-
- handler = k->sa.sa_handler;
- if (handler == SIG_DFL) {
- /* default handler : ignore some signal. The other are fatal */
- if (sig != SIGCHLD &&
- sig != SIGURG &&
- sig != SIGWINCH) {
- force_sig(sig);
- }
- } else if (handler == SIG_IGN) {
- /* ignore sig */
- } else if (handler == SIG_ERR) {
- force_sig(sig);
- } else {
-
- setup_frame(sig, k, 0, cpu_env);
- if (k->sa.sa_flags & SA_RESETHAND)
- k->sa.sa_handler = SIG_DFL;
- }
- if (q != &k->info)
- free_sigqueue(q);
-}
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