os: replace non-portable Waitmsg with portable ProcessState
Use methods for key questions.
Provide access to non-portable pieces through portable methods.
Windows and Plan 9 updated.
R=golang-dev, bradfitz, bradfitz, r, dsymonds, rsc, iant, iant
CC=golang-dev
https://golang.org/cl/5673077
diff --git a/src/cmd/cgo/util.go b/src/cmd/cgo/util.go
index 155c659..cd7cde2 100644
--- a/src/cmd/cgo/util.go
+++ b/src/cmd/cgo/util.go
@@ -56,11 +56,11 @@
<-c
<-c
- w, err := p.Wait()
+ state, err := p.Wait()
if err != nil {
fatalf("%s", err)
}
- ok = w.Exited() && w.ExitStatus() == 0
+ ok = state.Success()
return
}
diff --git a/src/cmd/godoc/main.go b/src/cmd/godoc/main.go
index 80cf618..8d59220 100644
--- a/src/cmd/godoc/main.go
+++ b/src/cmd/godoc/main.go
@@ -109,10 +109,10 @@
log.Printf("os.Wait(%d, 0): %v", p.Pid, err)
return 2
}
- status = wait.ExitStatus()
- if !wait.Exited() || status > 1 {
+ if !wait.Success() {
os.Stderr.Write(buf.Bytes())
- log.Printf("executing %v failed (exit status = %d)", args, status)
+ log.Printf("executing %v failed", args)
+ status = 1 // See comment in default case in dosync.
return
}
@@ -143,6 +143,8 @@
// don't change the package tree
syncDelay.set(time.Duration(*syncMin) * time.Minute) // revert to regular sync schedule
default:
+ // TODO(r): this cannot happen now, since Wait has a boolean exit condition,
+ // not an integer.
// sync failed because of an error - back off exponentially, but try at least once a day
syncDelay.backoff(24 * time.Hour)
}
diff --git a/src/pkg/os/exec/exec.go b/src/pkg/os/exec/exec.go
index 248d97d..ebe92a9 100644
--- a/src/pkg/os/exec/exec.go
+++ b/src/pkg/os/exec/exec.go
@@ -79,9 +79,9 @@
// Process is the underlying process, once started.
Process *os.Process
- // Waitmsg contains information about an exited process,
+ // ProcessState contains information about an exited process,
// available after a call to Wait or Run.
- Waitmsg *os.Waitmsg
+ ProcessState *os.ProcessState
err error // last error (from LookPath, stdin, stdout, stderr)
finished bool // when Wait was called
@@ -266,11 +266,11 @@
// An ExitError reports an unsuccessful exit by a command.
type ExitError struct {
- *os.Waitmsg
+ *os.ProcessState
}
func (e *ExitError) Error() string {
- return e.Waitmsg.String()
+ return e.ProcessState.String()
}
// Wait waits for the command to exit.
@@ -291,8 +291,8 @@
return errors.New("exec: Wait was already called")
}
c.finished = true
- msg, err := c.Process.Wait()
- c.Waitmsg = msg
+ state, err := c.Process.Wait()
+ c.ProcessState = state
var copyError error
for _ = range c.goroutine {
@@ -307,8 +307,8 @@
if err != nil {
return err
- } else if !msg.Exited() || msg.ExitStatus() != 0 {
- return &ExitError{msg}
+ } else if !state.Success() {
+ return &ExitError{state}
}
return copyError
diff --git a/src/pkg/os/exec_plan9.go b/src/pkg/os/exec_plan9.go
index 92126c1..9da86e2 100644
--- a/src/pkg/os/exec_plan9.go
+++ b/src/pkg/os/exec_plan9.go
@@ -8,6 +8,7 @@
"errors"
"runtime"
"syscall"
+ "time"
)
// StartProcess starts a new process with the program, arguments and attributes
@@ -64,14 +65,9 @@
return e
}
-// Waitmsg stores the information about an exited process as reported by Wait.
-type Waitmsg struct {
- syscall.Waitmsg
-}
-
// Wait waits for the Process to exit or stop, and then returns a
// Waitmsg describing its status and an error, if any.
-func (p *Process) Wait() (w *Waitmsg, err error) {
+func (p *Process) Wait() (ps *ProcessState, err error) {
var waitmsg syscall.Waitmsg
if p.Pid == -1 {
@@ -91,7 +87,11 @@
}
}
- return &Waitmsg{waitmsg}, nil
+ ps = &ProcessState{
+ pid: waitmsg.Pid,
+ status: waitmsg,
+ }
+ return ps, nil
}
// Release releases any resources associated with the Process.
@@ -108,9 +108,57 @@
return newProcess(pid, 0), nil
}
-func (w *Waitmsg) String() string {
- if w == nil {
+// ProcessState stores information about process as reported by Wait.
+type ProcessState struct {
+ pid int // The process's id.
+ status syscall.Waitmsg // System-dependent status info.
+}
+
+// Pid returns the process id of the exited process.
+func (p *ProcessState) Pid() int {
+ return p.pid
+}
+
+// Exited returns whether the program has exited.
+func (p *ProcessState) Exited() bool {
+ return p.status.Exited()
+}
+
+// Success reports whether the program exited successfully,
+// such as with exit status 0 on Unix.
+func (p *ProcessState) Success() bool {
+ return p.status.ExitStatus() == 0
+}
+
+// Sys returns system-dependent exit information about
+// the process. Convert it to the appropriate underlying
+// type, such as *syscall.Waitmsg on Plan 9, to access its contents.
+func (p *ProcessState) Sys() interface{} {
+ return &p.status
+}
+
+// SysUsage returns system-dependent resource usage information about
+// the exited process. Convert it to the appropriate underlying
+// type, such as *syscall.Waitmsg on Unix, to access its contents.
+func (p *ProcessState) SysUsage() interface{} {
+ return &p.status
+}
+
+// UserTime returns the user CPU time of the exited process and its children.
+// It is always reported as 0 on Windows.
+func (p *ProcessState) UserTime() time.Duration {
+ return time.Duration(p.status.Time[0]) * time.Millisecond
+}
+
+// SystemTime returns the system CPU time of the exited process and its children.
+// It is always reported as 0 on Windows.
+func (p *ProcessState) SystemTime() time.Duration {
+ return time.Duration(p.status.Time[1]) * time.Millisecond
+}
+
+func (p *ProcessState) String() string {
+ if p == nil {
return "<nil>"
}
- return "exit status: " + w.Msg
+ return "exit status: " + p.status.Msg
}
diff --git a/src/pkg/os/exec_posix.go b/src/pkg/os/exec_posix.go
index 03c7f0e..2b8d2b2 100644
--- a/src/pkg/os/exec_posix.go
+++ b/src/pkg/os/exec_posix.go
@@ -42,18 +42,41 @@
return p.Signal(Kill)
}
-// TODO(rsc): Should os implement its own syscall.WaitStatus
-// wrapper with the methods, or is exposing the underlying one enough?
-//
-// TODO(rsc): Certainly need to have Rusage struct,
-// since syscall one might have different field types across
-// different OS.
+// ProcessState stores information about process as reported by Wait.
+type ProcessState struct {
+ pid int // The process's id.
+ status *syscall.WaitStatus // System-dependent status info.
+ rusage *syscall.Rusage
+}
-// Waitmsg stores the information about an exited process as reported by Wait.
-type Waitmsg struct {
- Pid int // The process's id.
- syscall.WaitStatus // System-dependent status info.
- Rusage *syscall.Rusage // System-dependent resource usage info.
+// Pid returns the process id of the exited process.
+func (p *ProcessState) Pid() int {
+ return p.pid
+}
+
+// Exited returns whether the program has exited.
+func (p *ProcessState) Exited() bool {
+ return p.status.Exited()
+}
+
+// Success reports whether the program exited successfully,
+// such as with exit status 0 on Unix.
+func (p *ProcessState) Success() bool {
+ return p.status.ExitStatus() == 0
+}
+
+// Sys returns system-dependent exit information about
+// the process. Convert it to the appropriate underlying
+// type, such as *syscall.WaitStatus on Unix, to access its contents.
+func (p *ProcessState) Sys() interface{} {
+ return p.status
+}
+
+// SysUsage returns system-dependent resource usage information about
+// the exited process. Convert it to the appropriate underlying
+// type, such as *syscall.Rusage on Unix, to access its contents.
+func (p *ProcessState) SysUsage() interface{} {
+ return p.rusage
}
// Convert i to decimal string.
@@ -83,26 +106,26 @@
return string(b[bp:])
}
-func (w *Waitmsg) String() string {
- if w == nil {
+func (p *ProcessState) String() string {
+ if p == nil {
return "<nil>"
}
- // TODO(austin) Use signal names when possible?
+ status := p.Sys().(*syscall.WaitStatus)
res := ""
switch {
- case w.Exited():
- res = "exit status " + itod(w.ExitStatus())
- case w.Signaled():
- res = "signal " + itod(int(w.Signal()))
- case w.Stopped():
- res = "stop signal " + itod(int(w.StopSignal()))
- if w.StopSignal() == syscall.SIGTRAP && w.TrapCause() != 0 {
- res += " (trap " + itod(w.TrapCause()) + ")"
+ case status.Exited():
+ res = "exit status " + itod(status.ExitStatus())
+ case status.Signaled():
+ res = "signal " + itod(int(status.Signal()))
+ case status.Stopped():
+ res = "stop signal " + itod(int(status.StopSignal()))
+ if status.StopSignal() == syscall.SIGTRAP && status.TrapCause() != 0 {
+ res += " (trap " + itod(status.TrapCause()) + ")"
}
- case w.Continued():
+ case status.Continued():
res = "continued"
}
- if w.CoreDump() {
+ if status.CoreDump() {
res += " (core dumped)"
}
return res
diff --git a/src/pkg/os/exec_unix.go b/src/pkg/os/exec_unix.go
index b9880ff..e5905f0 100644
--- a/src/pkg/os/exec_unix.go
+++ b/src/pkg/os/exec_unix.go
@@ -10,26 +10,30 @@
"errors"
"runtime"
"syscall"
+ "time"
)
// Wait waits for the Process to exit or stop, and then returns a
-// Waitmsg describing its status and an error, if any.
-func (p *Process) Wait() (w *Waitmsg, err error) {
+// ProcessState describing its status and an error, if any.
+func (p *Process) Wait() (ps *ProcessState, err error) {
if p.Pid == -1 {
return nil, syscall.EINVAL
}
var status syscall.WaitStatus
- pid1, e := syscall.Wait4(p.Pid, &status, 0, nil)
+ var rusage syscall.Rusage
+ pid1, e := syscall.Wait4(p.Pid, &status, 0, &rusage)
if e != nil {
return nil, NewSyscallError("wait", e)
}
if pid1 != 0 {
p.done = true
}
- w = new(Waitmsg)
- w.Pid = pid1
- w.WaitStatus = status
- return w, nil
+ ps = &ProcessState{
+ pid: pid1,
+ status: &status,
+ rusage: &rusage,
+ }
+ return ps, nil
}
// Signal sends a signal to the Process.
@@ -60,3 +64,13 @@
// NOOP for unix.
return newProcess(pid, 0), nil
}
+
+// UserTime returns the user CPU time of the exited process and its children.
+func (p *ProcessState) UserTime() time.Duration {
+ return time.Duration(p.rusage.Utime.Nano()) * time.Nanosecond
+}
+
+// SystemTime returns the system CPU time of the exited process and its children.
+func (p *ProcessState) SystemTime() time.Duration {
+ return time.Duration(p.rusage.Stime.Nano()) * time.Nanosecond
+}
diff --git a/src/pkg/os/exec_windows.go b/src/pkg/os/exec_windows.go
index 7d46c89..8887ba4 100644
--- a/src/pkg/os/exec_windows.go
+++ b/src/pkg/os/exec_windows.go
@@ -8,12 +8,13 @@
"errors"
"runtime"
"syscall"
+ "time"
"unsafe"
)
// Wait waits for the Process to exit or stop, and then returns a
-// Waitmsg describing its status and an error, if any.
-func (p *Process) Wait() (w *Waitmsg, err error) {
+// ProcessState describing its status and an error, if any.
+func (p *Process) Wait() (ps *ProcessState, err error) {
s, e := syscall.WaitForSingleObject(syscall.Handle(p.handle), syscall.INFINITE)
switch s {
case syscall.WAIT_OBJECT_0:
@@ -29,7 +30,7 @@
return nil, NewSyscallError("GetExitCodeProcess", e)
}
p.done = true
- return &Waitmsg{p.Pid, syscall.WaitStatus{Status: s, ExitCode: ec}, new(syscall.Rusage)}, nil
+ return &ProcessState{p.Pid, &syscall.WaitStatus{Status: s, ExitCode: ec}, new(syscall.Rusage)}, nil
}
// Signal sends a signal to the Process.
@@ -83,3 +84,15 @@
Args[i] = string(syscall.UTF16ToString((*v)[:]))
}
}
+
+// UserTime returns the user CPU time of the exited process and its children.
+// For now, it is always reported as 0 on Windows.
+func (p *ProcessState) UserTime() time.Duration {
+ return 0
+}
+
+// SystemTime returns the system CPU time of the exited process and its children.
+// For now, it is always reported as 0 on Windows.
+func (p *ProcessState) SystemTime() time.Duration {
+ return 0
+}
diff --git a/src/pkg/os/os_test.go b/src/pkg/os/os_test.go
index 976d64b..21e2f37 100644
--- a/src/pkg/os/os_test.go
+++ b/src/pkg/os/os_test.go
@@ -1007,10 +1007,10 @@
}
}
-func TestNilWaitmsgString(t *testing.T) {
- var w *Waitmsg
- s := w.String()
+func TestNilProcessStateString(t *testing.T) {
+ var ps *ProcessState
+ s := ps.String()
if s != "<nil>" {
- t.Errorf("(*Waitmsg)(nil).String() = %q, want %q", s, "<nil>")
+ t.Errorf("(*ProcessState)(nil).String() = %q, want %q", s, "<nil>")
}
}
