delve/pkg/proc/native/threads_linux.go
2020-03-31 14:47:29 -07:00

118 lines
2.7 KiB
Go

package native
import (
"fmt"
sys "golang.org/x/sys/unix"
"github.com/go-delve/delve/pkg/proc"
)
type waitStatus sys.WaitStatus
// osSpecificDetails hold Linux specific
// process details.
type osSpecificDetails struct {
delayedSignal int
registers sys.PtraceRegs
running bool
setbp bool
}
func (t *nativeThread) stop() (err error) {
err = sys.Tgkill(t.dbp.pid, t.ID, sys.SIGSTOP)
if err != nil {
err = fmt.Errorf("stop err %s on thread %d", err, t.ID)
return
}
return
}
// Stopped returns whether the thread is stopped at
// the operating system level.
func (t *nativeThread) Stopped() bool {
state := status(t.ID, t.dbp.os.comm)
return state == statusTraceStop || state == statusTraceStopT
}
func (t *nativeThread) resume() error {
sig := t.os.delayedSignal
t.os.delayedSignal = 0
return t.resumeWithSig(sig)
}
func (t *nativeThread) resumeWithSig(sig int) (err error) {
t.os.running = true
t.dbp.execPtraceFunc(func() { err = ptraceCont(t.ID, sig) })
return
}
func (t *nativeThread) singleStep() (err error) {
for {
t.dbp.execPtraceFunc(func() { err = sys.PtraceSingleStep(t.ID) })
if err != nil {
return err
}
wpid, status, err := t.dbp.waitFast(t.ID)
if err != nil {
return err
}
if (status == nil || status.Exited()) && wpid == t.dbp.pid {
t.dbp.postExit()
rs := 0
if status != nil {
rs = status.ExitStatus()
}
return proc.ErrProcessExited{Pid: t.dbp.pid, Status: rs}
}
if wpid == t.ID && status.StopSignal() == sys.SIGTRAP {
return nil
}
}
}
func (t *nativeThread) Blocked() bool {
regs, err := t.Registers(false)
if err != nil {
return false
}
pc := regs.PC()
fn := t.BinInfo().PCToFunc(pc)
if fn != nil && ((fn.Name == "runtime.futex") || (fn.Name == "runtime.usleep") || (fn.Name == "runtime.clone")) {
return true
}
return false
}
func (t *nativeThread) WriteMemory(addr uintptr, data []byte) (written int, err error) {
if t.dbp.exited {
return 0, proc.ErrProcessExited{Pid: t.dbp.pid}
}
if len(data) == 0 {
return
}
// ProcessVmWrite can't poke read-only memory like ptrace, so don't
// even bother for small writes -- likely breakpoints and such.
if len(data) > sys.SizeofPtr {
written, _ = processVmWrite(t.ID, addr, data)
}
if written == 0 {
t.dbp.execPtraceFunc(func() { written, err = sys.PtracePokeData(t.ID, addr, data) })
}
return
}
func (t *nativeThread) ReadMemory(data []byte, addr uintptr) (n int, err error) {
if t.dbp.exited {
return 0, proc.ErrProcessExited{Pid: t.dbp.pid}
}
if len(data) == 0 {
return
}
n, _ = processVmRead(t.ID, addr, data)
if n == 0 {
t.dbp.execPtraceFunc(func() { n, err = sys.PtracePeekData(t.ID, addr, data) })
}
return
}