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// Copyright 2009 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
#include "runtime.h"
#include "defs_GOOS_GOARCH.h"
#include "signals_GOOS.h"
#include "os_GOOS.h"
void
runtime·dumpregs(Sigcontext *r)
{
runtime·printf("trap %x\n", r->trap_no);
runtime·printf("error %x\n", r->error_code);
runtime·printf("oldmask %x\n", r->oldmask);
runtime·printf("r0 %x\n", r->arm_r0);
runtime·printf("r1 %x\n", r->arm_r1);
runtime·printf("r2 %x\n", r->arm_r2);
runtime·printf("r3 %x\n", r->arm_r3);
runtime·printf("r4 %x\n", r->arm_r4);
runtime·printf("r5 %x\n", r->arm_r5);
runtime·printf("r6 %x\n", r->arm_r6);
runtime·printf("r7 %x\n", r->arm_r7);
runtime·printf("r8 %x\n", r->arm_r8);
runtime·printf("r9 %x\n", r->arm_r9);
runtime·printf("r10 %x\n", r->arm_r10);
runtime·printf("fp %x\n", r->arm_fp);
runtime·printf("ip %x\n", r->arm_ip);
runtime·printf("sp %x\n", r->arm_sp);
runtime·printf("lr %x\n", r->arm_lr);
runtime·printf("pc %x\n", r->arm_pc);
runtime·printf("cpsr %x\n", r->arm_cpsr);
runtime·printf("fault %x\n", r->fault_address);
}
/*
* This assembler routine takes the args from registers, puts them on the stack,
* and calls sighandler().
*/
extern void runtime·sigtramp(void);
extern void runtime·sigreturn(void); // calls runtime·sigreturn
void
runtime·sighandler(int32 sig, Siginfo *info, void *context, G *gp)
{
Ucontext *uc;
Sigcontext *r;
SigTab *t;
uc = context;
r = &uc->uc_mcontext;
if(sig == SIGPROF) {
runtime·sigprof((uint8*)r->arm_pc, (uint8*)r->arm_sp, (uint8*)r->arm_lr, gp);
return;
}
t = &runtime·sigtab[sig];
if(info->si_code != SI_USER && (t->flags & SigPanic)) {
if(gp == nil || gp == m->g0)
goto Throw;
// Make it look like a call to the signal func.
// Have to pass arguments out of band since
// augmenting the stack frame would break
// the unwinding code.
gp->sig = sig;
gp->sigcode0 = info->si_code;
gp->sigcode1 = r->fault_address;
gp->sigpc = r->arm_pc;
// We arrange lr, and pc to pretend the panicking
// function calls sigpanic directly.
// Always save LR to stack so that panics in leaf
// functions are correctly handled. This smashes
// the stack frame but we're not going back there
// anyway.
r->arm_sp -= 4;
*(uint32 *)r->arm_sp = r->arm_lr;
// Don't bother saving PC if it's zero, which is
// probably a call to a nil func: the old link register
// is more useful in the stack trace.
if(r->arm_pc != 0)
r->arm_lr = r->arm_pc;
// In case we are panicking from external C code
r->arm_r10 = (uintptr)gp;
r->arm_r9 = (uintptr)m;
r->arm_pc = (uintptr)runtime·sigpanic;
return;
}
if(info->si_code == SI_USER || (t->flags & SigNotify))
if(runtime·sigsend(sig))
return;
if(t->flags & SigKill)
runtime·exit(2);
if(!(t->flags & SigThrow))
return;
Throw:
if(runtime·panicking) // traceback already printed
runtime·exit(2);
runtime·panicking = 1;
if(sig < 0 || sig >= NSIG)
runtime·printf("Signal %d\n", sig);
else
runtime·printf("%s\n", runtime·sigtab[sig].name);
runtime·printf("PC=%x\n", r->arm_pc);
if(m->lockedg != nil && m->ncgo > 0 && gp == m->g0) {
runtime·printf("signal arrived during cgo execution\n");
gp = m->lockedg;
}
runtime·printf("\n");
if(runtime·gotraceback()){
runtime·traceback((void*)r->arm_pc, (void*)r->arm_sp, (void*)r->arm_lr, gp);
runtime·tracebackothers(gp);
runtime·printf("\n");
runtime·dumpregs(r);
}
// breakpoint();
runtime·exit(2);
}
void
runtime·signalstack(byte *p, int32 n)
{
Sigaltstack st;
st.ss_sp = p;
st.ss_size = n;
st.ss_flags = 0;
if(p == nil)
st.ss_flags = SS_DISABLE;
runtime·sigaltstack(&st, nil);
}
void
runtime·setsig(int32 i, void (*fn)(int32, Siginfo*, void*, G*), bool restart)
{
Sigaction sa;
// If SIGHUP handler is SIG_IGN, assume running
// under nohup and do not set explicit handler.
if(i == SIGHUP) {
runtime·memclr((byte*)&sa, sizeof sa);
if(runtime·rt_sigaction(i, nil, &sa, sizeof(sa.sa_mask)) != 0)
runtime·throw("rt_sigaction read failure");
if(sa.sa_handler == SIG_IGN)
return;
}
runtime·memclr((byte*)&sa, sizeof sa);
sa.sa_flags = SA_ONSTACK | SA_SIGINFO | SA_RESTORER;
if(restart)
sa.sa_flags |= SA_RESTART;
sa.sa_mask = ~0ULL;
sa.sa_restorer = (void*)runtime·sigreturn;
if(fn == runtime·sighandler)
fn = (void*)runtime·sigtramp;
sa.sa_handler = fn;
if(runtime·rt_sigaction(i, &sa, nil, sizeof(sa.sa_mask)) != 0)
runtime·throw("rt_sigaction failure");
}
#define AT_NULL 0
#define AT_PLATFORM 15 // introduced in at least 2.6.11
#define AT_HWCAP 16 // introduced in at least 2.6.11
#define AT_RANDOM 25 // introduced in 2.6.29
#define HWCAP_VFP (1 << 6) // introduced in at least 2.6.11
#define HWCAP_VFPv3 (1 << 13) // introduced in 2.6.30
static uint32 runtime·randomNumber;
uint8 runtime·armArch = 6; // we default to ARMv6
uint32 runtime·hwcap; // set by setup_auxv
uint8 runtime·goarm; // set by 5l
void
runtime·checkgoarm(void)
{
if(runtime·goarm > 5 && !(runtime·hwcap & HWCAP_VFP)) {
runtime·printf("runtime: this CPU has no floating point hardware, so it cannot run\n");
runtime·printf("this GOARM=%d binary. Recompile using GOARM=5.\n", runtime·goarm);
runtime·exit(1);
}
if(runtime·goarm > 6 && !(runtime·hwcap & HWCAP_VFPv3)) {
runtime·printf("runtime: this CPU has no VFPv3 floating point hardware, so it cannot run\n");
runtime·printf("this GOARM=%d binary. Recompile using GOARM=6.\n", runtime·goarm);
runtime·exit(1);
}
}
#pragma textflag 7
void
runtime·setup_auxv(int32 argc, void *argv_list)
{
byte **argv;
byte **envp;
byte *rnd;
uint32 *auxv;
uint32 t;
argv = &argv_list;
// skip envp to get to ELF auxiliary vector.
for(envp = &argv[argc+1]; *envp != nil; envp++)
;
envp++;
for(auxv=(uint32*)envp; auxv[0] != AT_NULL; auxv += 2) {
switch(auxv[0]) {
case AT_RANDOM: // kernel provided 16-byte worth of random data
if(auxv[1]) {
rnd = (byte*)auxv[1];
runtime·randomNumber = rnd[4] | rnd[5]<<8 | rnd[6]<<16 | rnd[7]<<24;
}
break;
case AT_PLATFORM: // v5l, v6l, v7l
if(auxv[1]) {
t = *(uint8*)(auxv[1]+1);
if(t >= '5' && t <= '7')
runtime·armArch = t - '0';
}
break;
case AT_HWCAP: // CPU capability bit flags
runtime·hwcap = auxv[1];
break;
}
}
}
#pragma textflag 7
int64
runtime·cputicks(void)
{
// Currently cputicks() is used in blocking profiler and to seed runtime·fastrand1().
// runtime·nanotime() is a poor approximation of CPU ticks that is enough for the profiler.
// runtime·randomNumber provides better seeding of fastrand1.
return runtime·nanotime() + runtime·randomNumber;
}
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