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qemu/linux-user/signal.c
bellard 3ef693a032 distribution patches 
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@44 c046a42c-6fe2-441c-8c8c-71466251a162
2003-03-23 20:17:16 +00:00

911 lines
24 KiB
C
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/*
* 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, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <stdarg.h>
#include <signal.h>
#include <errno.h>
#include <sys/ucontext.h>
#include "qemu.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 emulated_sigaction sigact_table[TARGET_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);
/* XXX: do it properly */
static inline int host_to_target_signal(int sig)
{
return sig;
}
static inline int target_to_host_signal(int sig)
{
return sig;
}
void host_to_target_sigset(target_sigset_t *d, sigset_t *s)
{
int i;
for(i = 0;i < TARGET_NSIG_WORDS; i++) {
d->sig[i] = tswapl(((unsigned long *)s)[i]);
}
}
void target_to_host_sigset(sigset_t *d, target_sigset_t *s)
{
int i;
for(i = 0;i < TARGET_NSIG_WORDS; i++) {
((unsigned long *)d)[i] = tswapl(s->sig[i]);
}
}
void host_to_target_old_sigset(target_ulong *old_sigset,
const sigset_t *sigset)
{
*old_sigset = tswap32(*(unsigned long *)sigset & 0xffffffff);
}
void target_to_host_old_sigset(sigset_t *sigset,
const target_ulong *old_sigset)
{
sigemptyset(sigset);
*(unsigned long *)sigset = tswapl(*old_sigset);
}
/* siginfo conversion */
static inline void host_to_target_siginfo_noswap(target_siginfo_t *tinfo,
const siginfo_t *info)
{
int sig;
sig = host_to_target_signal(info->si_signo);
tinfo->si_signo = sig;
tinfo->si_errno = 0;
tinfo->si_code = 0;
if (sig == SIGILL || sig == SIGFPE || sig == SIGSEGV || sig == SIGBUS) {
/* should never come here, but who knows. The information for
the target is irrelevant */
tinfo->_sifields._sigfault._addr = 0;
} else if (sig >= TARGET_SIGRTMIN) {
tinfo->_sifields._rt._pid = info->si_pid;
tinfo->_sifields._rt._uid = info->si_uid;
/* XXX: potential problem if 64 bit */
tinfo->_sifields._rt._sigval.sival_ptr =
(target_ulong)info->si_value.sival_ptr;
}
}
static void tswap_siginfo(target_siginfo_t *tinfo,
const target_siginfo_t *info)
{
int sig;
sig = info->si_signo;
tinfo->si_signo = tswap32(sig);
tinfo->si_errno = tswap32(info->si_errno);
tinfo->si_code = tswap32(info->si_code);
if (sig == SIGILL || sig == SIGFPE || sig == SIGSEGV || sig == SIGBUS) {
tinfo->_sifields._sigfault._addr =
tswapl(info->_sifields._sigfault._addr);
} else if (sig >= TARGET_SIGRTMIN) {
tinfo->_sifields._rt._pid = tswap32(info->_sifields._rt._pid);
tinfo->_sifields._rt._uid = tswap32(info->_sifields._rt._uid);
tinfo->_sifields._rt._sigval.sival_ptr =
tswapl(info->_sifields._rt._sigval.sival_ptr);
}
}
void host_to_target_siginfo(target_siginfo_t *tinfo, const siginfo_t *info)
{
host_to_target_siginfo_noswap(tinfo, info);
tswap_siginfo(tinfo, tinfo);
}
/* XXX: we support only POSIX RT signals are used. */
/* XXX: find a solution for 64 bit (additionnal malloced data is needed) */
void target_to_host_siginfo(siginfo_t *info, const target_siginfo_t *tinfo)
{
info->si_signo = tswap32(tinfo->si_signo);
info->si_errno = tswap32(tinfo->si_errno);
info->si_code = tswap32(tinfo->si_code);
info->si_pid = tswap32(tinfo->_sifields._rt._pid);
info->si_uid = tswap32(tinfo->_sifields._rt._uid);
info->si_value.sival_ptr =
(void *)tswapl(tinfo->_sifields._rt._sigval.sival_ptr);
}
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 __attribute((noreturn)) force_sig(int sig)
{
int host_sig;
host_sig = target_to_host_signal(sig);
fprintf(stderr, "gemu: uncaught target signal %d (%s) - exiting\n",
sig, strsignal(host_sig));
#if 1
_exit(-host_sig);
#else
{
struct sigaction act;
sigemptyset(&act.sa_mask);
act.sa_flags = SA_SIGINFO;
act.sa_sigaction = SIG_DFL;
sigaction(SIGABRT, &act, NULL);
abort();
}
#endif
}
/* 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_sigal: sig=%d\n",
sig);
#endif
k = &sigact_table[sig - 1];
handler = k->sa._sa_handler;
if (handler == TARGET_SIG_DFL) {
/* default handler : ignore some signal. The other are fatal */
if (sig != TARGET_SIGCHLD &&
sig != TARGET_SIGURG &&
sig != TARGET_SIGWINCH) {
force_sig(sig);
} else {
return 0; /* indicate ignored */
}
} else if (handler == TARGET_SIG_IGN) {
/* ignore signal */
return 0;
} else if (handler == TARGET_SIG_ERR) {
force_sig(sig);
} else {
pq = &k->first;
if (sig < TARGET_SIGRTMIN) {
/* if non real time signal, we queue exactly one signal */
if (!k->pending)
q = &k->info;
else
return 0;
} else {
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 */
}
}
#if defined(DEBUG_SIGNAL)
#ifdef __i386__
static void dump_regs(struct ucontext *uc)
{
fprintf(stderr,
"EAX=%08x EBX=%08x ECX=%08x EDX=%08x\n"
"ESI=%08x EDI=%08x EBP=%08x ESP=%08x\n"
"EFL=%08x EIP=%08x\n",
uc->uc_mcontext.gregs[EAX],
uc->uc_mcontext.gregs[EBX],
uc->uc_mcontext.gregs[ECX],
uc->uc_mcontext.gregs[EDX],
uc->uc_mcontext.gregs[ESI],
uc->uc_mcontext.gregs[EDI],
uc->uc_mcontext.gregs[EBP],
uc->uc_mcontext.gregs[ESP],
uc->uc_mcontext.gregs[EFL],
uc->uc_mcontext.gregs[EIP]);
}
#else
static void dump_regs(struct ucontext *uc)
{
}
#endif
#endif
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_x86_signal_handler(host_signum, info, puc))
return;
}
/* get target signal number */
sig = host_to_target_signal(host_signum);
if (sig < 1 || sig > TARGET_NSIG)
return;
#if defined(DEBUG_SIGNAL)
fprintf(stderr, "gemu: got signal %d\n", sig);
dump_regs(puc);
#endif
host_to_target_siginfo_noswap(&tinfo, info);
if (queue_signal(sig, &tinfo) == 1) {
/* interrupt the virtual CPU as soon as possible */
cpu_x86_interrupt(global_env);
}
}
int do_sigaction(int sig, const struct target_sigaction *act,
struct target_sigaction *oact)
{
struct emulated_sigaction *k;
if (sig < 1 || sig > TARGET_NSIG)
return -EINVAL;
k = &sigact_table[sig - 1];
#if defined(DEBUG_SIGNAL) && 0
fprintf(stderr, "sigaction sig=%d act=0x%08x, oact=0x%08x\n",
sig, (int)act, (int)oact);
#endif
if (oact) {
oact->_sa_handler = tswapl(k->sa._sa_handler);
oact->sa_flags = tswapl(k->sa.sa_flags);
oact->sa_restorer = tswapl(k->sa.sa_restorer);
oact->sa_mask = k->sa.sa_mask;
}
if (act) {
k->sa._sa_handler = tswapl(act->_sa_handler);
k->sa.sa_flags = tswapl(act->sa_flags);
k->sa.sa_restorer = tswapl(act->sa_restorer);
k->sa.sa_mask = act->sa_mask;
}
return 0;
}
#ifdef TARGET_I386
/* from the Linux kernel */
struct target_fpreg {
uint16_t significand[4];
uint16_t exponent;
};
struct target_fpxreg {
uint16_t significand[4];
uint16_t exponent;
uint16_t padding[3];
};
struct target_xmmreg {
target_ulong element[4];
};
struct target_fpstate {
/* Regular FPU environment */
target_ulong cw;
target_ulong sw;
target_ulong tag;
target_ulong ipoff;
target_ulong cssel;
target_ulong dataoff;
target_ulong datasel;
struct target_fpreg _st[8];
uint16_t status;
uint16_t magic; /* 0xffff = regular FPU data only */
/* FXSR FPU environment */
target_ulong _fxsr_env[6]; /* FXSR FPU env is ignored */
target_ulong mxcsr;
target_ulong reserved;
struct target_fpxreg _fxsr_st[8]; /* FXSR FPU reg data is ignored */
struct target_xmmreg _xmm[8];
target_ulong padding[56];
};
#define X86_FXSR_MAGIC 0x0000
struct target_sigcontext {
uint16_t gs, __gsh;
uint16_t fs, __fsh;
uint16_t es, __esh;
uint16_t ds, __dsh;
target_ulong edi;
target_ulong esi;
target_ulong ebp;
target_ulong esp;
target_ulong ebx;
target_ulong edx;
target_ulong ecx;
target_ulong eax;
target_ulong trapno;
target_ulong err;
target_ulong eip;
uint16_t cs, __csh;
target_ulong eflags;
target_ulong esp_at_signal;
uint16_t ss, __ssh;
target_ulong fpstate; /* pointer */
target_ulong oldmask;
target_ulong cr2;
};
typedef struct target_sigaltstack {
target_ulong ss_sp;
int ss_flags;
target_ulong ss_size;
} target_stack_t;
struct target_ucontext {
target_ulong uc_flags;
target_ulong uc_link;
target_stack_t uc_stack;
struct target_sigcontext uc_mcontext;
target_sigset_t uc_sigmask; /* mask last for extensibility */
};
struct sigframe
{
target_ulong pretcode;
int sig;
struct target_sigcontext sc;
struct target_fpstate fpstate;
target_ulong extramask[TARGET_NSIG_WORDS-1];
char retcode[8];
};
struct rt_sigframe
{
target_ulong pretcode;
int sig;
target_ulong pinfo;
target_ulong puc;
struct target_siginfo info;
struct target_ucontext uc;
struct target_fpstate fpstate;
char retcode[8];
};
/*
* Set up a signal frame.
*/
#define __put_user(x,ptr)\
({\
int size = sizeof(*ptr);\
switch(size) {\
case 1:\
stb(ptr, (typeof(*ptr))(x));\
break;\
case 2:\
stw(ptr, (typeof(*ptr))(x));\
break;\
case 4:\
stl(ptr, (typeof(*ptr))(x));\
break;\
case 8:\
stq(ptr, (typeof(*ptr))(x));\
break;\
default:\
abort();\
}\
0;\
})
#define get_user(val, ptr) (typeof(*ptr))(*(ptr))
#define __copy_to_user(dst, src, size)\
({\
memcpy(dst, src, size);\
0;\
})
static inline int copy_siginfo_to_user(target_siginfo_t *tinfo,
const target_siginfo_t *info)
{
tswap_siginfo(tinfo, info);
return 0;
}
/* XXX: save x87 state */
static int
setup_sigcontext(struct target_sigcontext *sc, struct target_fpstate *fpstate,
CPUX86State *env, unsigned long mask)
{
int err = 0;
err |= __put_user(env->segs[R_GS], (unsigned int *)&sc->gs);
err |= __put_user(env->segs[R_FS], (unsigned int *)&sc->fs);
err |= __put_user(env->segs[R_ES], (unsigned int *)&sc->es);
err |= __put_user(env->segs[R_DS], (unsigned int *)&sc->ds);
err |= __put_user(env->regs[R_EDI], &sc->edi);
err |= __put_user(env->regs[R_ESI], &sc->esi);
err |= __put_user(env->regs[R_EBP], &sc->ebp);
err |= __put_user(env->regs[R_ESP], &sc->esp);
err |= __put_user(env->regs[R_EBX], &sc->ebx);
err |= __put_user(env->regs[R_EDX], &sc->edx);
err |= __put_user(env->regs[R_ECX], &sc->ecx);
err |= __put_user(env->regs[R_EAX], &sc->eax);
err |= __put_user(/*current->thread.trap_no*/ 0, &sc->trapno);
err |= __put_user(/*current->thread.error_code*/ 0, &sc->err);
err |= __put_user(env->eip, &sc->eip);
err |= __put_user(env->segs[R_CS], (unsigned int *)&sc->cs);
err |= __put_user(env->eflags, &sc->eflags);
err |= __put_user(env->regs[R_ESP], &sc->esp_at_signal);
err |= __put_user(env->segs[R_SS], (unsigned int *)&sc->ss);
#if 0
tmp = save_i387(fpstate);
if (tmp < 0)
err = 1;
else
err |= __put_user(tmp ? fpstate : NULL, &sc->fpstate);
#else
err |= __put_user(0, &sc->fpstate);
#endif
/* non-iBCS2 extensions.. */
err |= __put_user(mask, &sc->oldmask);
err |= __put_user(/*current->thread.cr2*/ 0, &sc->cr2);
return err;
}
/*
* Determine which stack to use..
*/
static inline void *
get_sigframe(struct emulated_sigaction *ka, CPUX86State *env, size_t frame_size)
{
unsigned long esp;
/* Default to using normal stack */
esp = env->regs[R_ESP];
#if 0
/* This is the X/Open sanctioned signal stack switching. */
if (ka->sa.sa_flags & SA_ONSTACK) {
if (sas_ss_flags(esp) == 0)
esp = current->sas_ss_sp + current->sas_ss_size;
}
/* This is the legacy signal stack switching. */
else if ((regs->xss & 0xffff) != __USER_DS &&
!(ka->sa.sa_flags & SA_RESTORER) &&
ka->sa.sa_restorer) {
esp = (unsigned long) ka->sa.sa_restorer;
}
#endif
return (void *)((esp - frame_size) & -8ul);
}
#define TF_MASK TRAP_FLAG
static void setup_frame(int sig, struct emulated_sigaction *ka,
target_sigset_t *set, CPUX86State *env)
{
struct sigframe *frame;
int err = 0;
frame = get_sigframe(ka, env, sizeof(*frame));
#if 0
if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
goto give_sigsegv;
#endif
err |= __put_user((/*current->exec_domain
&& current->exec_domain->signal_invmap
&& sig < 32
? current->exec_domain->signal_invmap[sig]
: */ sig),
&frame->sig);
if (err)
goto give_sigsegv;
setup_sigcontext(&frame->sc, &frame->fpstate, env, set->sig[0]);
if (err)
goto give_sigsegv;
if (TARGET_NSIG_WORDS > 1) {
err |= __copy_to_user(frame->extramask, &set->sig[1],
sizeof(frame->extramask));
}
if (err)
goto give_sigsegv;
/* Set up to return from userspace. If provided, use a stub
already in userspace. */
if (ka->sa.sa_flags & TARGET_SA_RESTORER) {
err |= __put_user(ka->sa.sa_restorer, &frame->pretcode);
} else {
err |= __put_user(frame->retcode, &frame->pretcode);
/* This is popl %eax ; movl $,%eax ; int $0x80 */
err |= __put_user(0xb858, (short *)(frame->retcode+0));
err |= __put_user(TARGET_NR_sigreturn, (int *)(frame->retcode+2));
err |= __put_user(0x80cd, (short *)(frame->retcode+6));
}
if (err)
goto give_sigsegv;
/* Set up registers for signal handler */
env->regs[R_ESP] = (unsigned long) frame;
env->eip = (unsigned long) ka->sa._sa_handler;
cpu_x86_load_seg(env, R_DS, __USER_DS);
cpu_x86_load_seg(env, R_ES, __USER_DS);
cpu_x86_load_seg(env, R_SS, __USER_DS);
cpu_x86_load_seg(env, R_CS, __USER_CS);
env->eflags &= ~TF_MASK;
return;
give_sigsegv:
if (sig == TARGET_SIGSEGV)
ka->sa._sa_handler = TARGET_SIG_DFL;
force_sig(TARGET_SIGSEGV /* , current */);
}
static void setup_rt_frame(int sig, struct emulated_sigaction *ka,
target_siginfo_t *info,
target_sigset_t *set, CPUX86State *env)
{
struct rt_sigframe *frame;
int err = 0;
frame = get_sigframe(ka, env, sizeof(*frame));
#if 0
if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
goto give_sigsegv;
#endif
err |= __put_user((/*current->exec_domain
&& current->exec_domain->signal_invmap
&& sig < 32
? current->exec_domain->signal_invmap[sig]
: */sig),
&frame->sig);
err |= __put_user((target_ulong)&frame->info, &frame->pinfo);
err |= __put_user((target_ulong)&frame->uc, &frame->puc);
err |= copy_siginfo_to_user(&frame->info, info);
if (err)
goto give_sigsegv;
/* Create the ucontext. */
err |= __put_user(0, &frame->uc.uc_flags);
err |= __put_user(0, &frame->uc.uc_link);
err |= __put_user(/*current->sas_ss_sp*/ 0, &frame->uc.uc_stack.ss_sp);
err |= __put_user(/* sas_ss_flags(regs->esp) */ 0,
&frame->uc.uc_stack.ss_flags);
err |= __put_user(/* current->sas_ss_size */ 0, &frame->uc.uc_stack.ss_size);
err |= setup_sigcontext(&frame->uc.uc_mcontext, &frame->fpstate,
env, set->sig[0]);
err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
if (err)
goto give_sigsegv;
/* Set up to return from userspace. If provided, use a stub
already in userspace. */
if (ka->sa.sa_flags & TARGET_SA_RESTORER) {
err |= __put_user(ka->sa.sa_restorer, &frame->pretcode);
} else {
err |= __put_user(frame->retcode, &frame->pretcode);
/* This is movl $,%eax ; int $0x80 */
err |= __put_user(0xb8, (char *)(frame->retcode+0));
err |= __put_user(TARGET_NR_rt_sigreturn, (int *)(frame->retcode+1));
err |= __put_user(0x80cd, (short *)(frame->retcode+5));
}
if (err)
goto give_sigsegv;
/* Set up registers for signal handler */
env->regs[R_ESP] = (unsigned long) frame;
env->eip = (unsigned long) ka->sa._sa_handler;
cpu_x86_load_seg(env, R_DS, __USER_DS);
cpu_x86_load_seg(env, R_ES, __USER_DS);
cpu_x86_load_seg(env, R_SS, __USER_DS);
cpu_x86_load_seg(env, R_CS, __USER_CS);
env->eflags &= ~TF_MASK;
return;
give_sigsegv:
if (sig == TARGET_SIGSEGV)
ka->sa._sa_handler = TARGET_SIG_DFL;
force_sig(TARGET_SIGSEGV /* , current */);
}
static int
restore_sigcontext(CPUX86State *env, struct target_sigcontext *sc, int *peax)
{
unsigned int err = 0;
#define COPY(x) err |= __get_user(regs->x, &sc->x)
#define COPY_SEG(seg) \
{ unsigned short tmp; \
err |= __get_user(tmp, &sc->seg); \
regs->x##seg = tmp; }
#define COPY_SEG_STRICT(seg) \
{ unsigned short tmp; \
err |= __get_user(tmp, &sc->seg); \
regs->x##seg = tmp|3; }
#define GET_SEG(seg) \
{ unsigned short tmp; \
err |= __get_user(tmp, &sc->seg); \
loadsegment(seg,tmp); }
cpu_x86_load_seg(env, R_GS, lduw(&sc->gs));
cpu_x86_load_seg(env, R_FS, lduw(&sc->fs));
cpu_x86_load_seg(env, R_ES, lduw(&sc->es));
cpu_x86_load_seg(env, R_DS, lduw(&sc->ds));
env->regs[R_EDI] = ldl(&sc->edi);
env->regs[R_ESI] = ldl(&sc->esi);
env->regs[R_EBP] = ldl(&sc->ebp);
env->regs[R_ESP] = ldl(&sc->esp);
env->regs[R_EBX] = ldl(&sc->ebx);
env->regs[R_EDX] = ldl(&sc->edx);
env->regs[R_ECX] = ldl(&sc->ecx);
env->eip = ldl(&sc->eip);
cpu_x86_load_seg(env, R_CS, lduw(&sc->cs) | 3);
cpu_x86_load_seg(env, R_SS, lduw(&sc->ss) | 3);
{
unsigned int tmpflags;
tmpflags = ldl(&sc->eflags);
env->eflags = (env->eflags & ~0x40DD5) | (tmpflags & 0x40DD5);
// regs->orig_eax = -1; /* disable syscall checks */
}
#if 0
{
struct _fpstate * buf;
err |= __get_user(buf, &sc->fpstate);
if (buf) {
if (verify_area(VERIFY_READ, buf, sizeof(*buf)))
goto badframe;
err |= restore_i387(buf);
}
}
#endif
*peax = ldl(&sc->eax);
return err;
#if 0
badframe:
return 1;
#endif
}
long do_sigreturn(CPUX86State *env)
{
struct sigframe *frame = (struct sigframe *)(env->regs[R_ESP] - 8);
target_sigset_t target_set;
sigset_t set;
int eax, i;
/* set blocked signals */
target_set.sig[0] = frame->sc.oldmask;
for(i = 1; i < TARGET_NSIG_WORDS; i++)
target_set.sig[i] = frame->extramask[i - 1];
target_to_host_sigset(&set, &target_set);
sigprocmask(SIG_SETMASK, &set, NULL);
/* restore registers */
if (restore_sigcontext(env, &frame->sc, &eax))
goto badframe;
return eax;
badframe:
force_sig(TARGET_SIGSEGV);
return 0;
}
long do_rt_sigreturn(CPUX86State *env)
{
struct rt_sigframe *frame = (struct rt_sigframe *)(env->regs[R_ESP] - 4);
target_sigset_t target_set;
sigset_t set;
// stack_t st;
int eax;
#if 0
if (verify_area(VERIFY_READ, frame, sizeof(*frame)))
goto badframe;
#endif
memcpy(&target_set, &frame->uc.uc_sigmask, sizeof(target_sigset_t));
target_to_host_sigset(&set, &target_set);
sigprocmask(SIG_SETMASK, &set, NULL);
if (restore_sigcontext(env, &frame->uc.uc_mcontext, &eax))
goto badframe;
#if 0
if (__copy_from_user(&st, &frame->uc.uc_stack, sizeof(st)))
goto badframe;
/* It is more difficult to avoid calling this function than to
call it and ignore errors. */
do_sigaltstack(&st, NULL, regs->esp);
#endif
return eax;
badframe:
force_sig(TARGET_SIGSEGV);
return 0;
}
#endif
void process_pending_signals(void *cpu_env)
{
int sig;
target_ulong handler;
sigset_t set, old_set;
target_sigset_t target_old_set;
struct emulated_sigaction *k;
struct sigqueue *q;
if (!signal_pending)
return;
k = sigact_table;
for(sig = 1; sig <= TARGET_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, "gemu: process signal %d\n", sig);
#endif
/* dequeue signal */
q = k->first;
k->first = q->next;
if (!k->first)
k->pending = 0;
handler = k->sa._sa_handler;
if (handler == TARGET_SIG_DFL) {
/* default handler : ignore some signal. The other are fatal */
if (sig != TARGET_SIGCHLD &&
sig != TARGET_SIGURG &&
sig != TARGET_SIGWINCH) {
force_sig(sig);
}
} else if (handler == TARGET_SIG_IGN) {
/* ignore sig */
} else if (handler == TARGET_SIG_ERR) {
force_sig(sig);
} else {
/* compute the blocked signals during the handler execution */
target_to_host_sigset(&set, &k->sa.sa_mask);
/* SA_NODEFER indicates that the current signal should not be
blocked during the handler */
if (!(k->sa.sa_flags & TARGET_SA_NODEFER))
sigaddset(&set, target_to_host_signal(sig));
/* block signals in the handler using Linux */
sigprocmask(SIG_BLOCK, &set, &old_set);
/* save the previous blocked signal state to restore it at the
end of the signal execution (see do_sigreturn) */
host_to_target_sigset(&target_old_set, &old_set);
/* prepare the stack frame of the virtual CPU */
if (k->sa.sa_flags & TARGET_SA_SIGINFO)
setup_rt_frame(sig, k, &q->info, &target_old_set, cpu_env);
else
setup_frame(sig, k, &target_old_set, cpu_env);
if (k->sa.sa_flags & TARGET_SA_RESETHAND)
k->sa._sa_handler = TARGET_SIG_DFL;
}
if (q != &k->info)
free_sigqueue(q);
}
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