| // Copyright 2014 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. |
| |
| package runtime |
| |
| import "unsafe" |
| |
| type sigctxt struct { |
| info *siginfo |
| ctxt unsafe.Pointer |
| } |
| |
| func (c *sigctxt) regs() *regs32 { return &(*ucontext)(c.ctxt).uc_mcontext.ss } |
| func (c *sigctxt) r0() uint32 { return c.regs().r[0] } |
| func (c *sigctxt) r1() uint32 { return c.regs().r[1] } |
| func (c *sigctxt) r2() uint32 { return c.regs().r[2] } |
| func (c *sigctxt) r3() uint32 { return c.regs().r[3] } |
| func (c *sigctxt) r4() uint32 { return c.regs().r[4] } |
| func (c *sigctxt) r5() uint32 { return c.regs().r[5] } |
| func (c *sigctxt) r6() uint32 { return c.regs().r[6] } |
| func (c *sigctxt) r7() uint32 { return c.regs().r[7] } |
| func (c *sigctxt) r8() uint32 { return c.regs().r[8] } |
| func (c *sigctxt) r9() uint32 { return c.regs().r[9] } |
| func (c *sigctxt) r10() uint32 { return c.regs().r[10] } |
| func (c *sigctxt) fp() uint32 { return c.regs().r[11] } |
| func (c *sigctxt) ip() uint32 { return c.regs().r[12] } |
| func (c *sigctxt) sp() uint32 { return c.regs().sp } |
| func (c *sigctxt) lr() uint32 { return c.regs().lr } |
| func (c *sigctxt) pc() uint32 { return c.regs().pc } |
| func (c *sigctxt) cpsr() uint32 { return c.regs().cpsr } |
| func (c *sigctxt) fault() uint32 { return c.info.si_addr } |
| func (c *sigctxt) sigcode() uint32 { return uint32(c.info.si_code) } |
| func (c *sigctxt) trap() uint32 { return 0 } |
| func (c *sigctxt) error() uint32 { return 0 } |
| func (c *sigctxt) oldmask() uint32 { return 0 } |
| |
| func (c *sigctxt) set_pc(x uint32) { c.regs().pc = x } |
| func (c *sigctxt) set_sp(x uint32) { c.regs().sp = x } |
| func (c *sigctxt) set_lr(x uint32) { c.regs().lr = x } |
| func (c *sigctxt) set_r10(x uint32) { c.regs().r[10] = x } |
| |
| func (c *sigctxt) set_sigcode(x uint32) { c.info.si_code = int32(x) } |
| func (c *sigctxt) set_sigaddr(x uint32) { c.info.si_addr = x } |
| |
| func (c *sigctxt) fixsigcode(sig uint32) { |
| switch sig { |
| case _SIGTRAP: |
| // OS X sets c.sigcode() == TRAP_BRKPT unconditionally for all SIGTRAPs, |
| // leaving no way to distinguish a breakpoint-induced SIGTRAP |
| // from an asynchronous signal SIGTRAP. |
| // They all look breakpoint-induced by default. |
| // Try looking at the code to see if it's a breakpoint. |
| // The assumption is that we're very unlikely to get an |
| // asynchronous SIGTRAP at just the moment that the |
| // PC started to point at unmapped memory. |
| pc := uintptr(c.pc()) |
| // OS X will leave the pc just after the instruction. |
| code := (*uint32)(unsafe.Pointer(pc - 4)) |
| if *code != 0xe7f001f0 { |
| // SIGTRAP on something other than breakpoint. |
| c.set_sigcode(_SI_USER) |
| } |
| } |
| } |