Merge pull request #34 from arduino/kill_process_darwin

`Kill` now kills all the childrens in the process-tree on MacOS and Windows.

Author: cmaglie

go.mod

@@ -1,8 +1,13 @@
 module github.com/arduino/go-paths-helper
 
-go 1.21
+go 1.23.0
 
-require github.com/stretchr/testify v1.8.4
+toolchain go1.23.2
+
+require (
+	github.com/stretchr/testify v1.8.4
+	golang.org/x/sys v0.32.0
+)
 
 require (
 	github.com/davecgh/go-spew v1.1.1 // indirect

go.sum

@@ -4,6 +4,8 @@ github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZb
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/stretchr/testify v1.8.4 h1:CcVxjf3Q8PM0mHUKJCdn+eZZtm5yQwehR5yeSVQQcUk=
 github.com/stretchr/testify v1.8.4/go.mod h1:sz/lmYIOXD/1dqDmKjjqLyZ2RngseejIcXlSw2iwfAo=
+golang.org/x/sys v0.32.0 h1:s77OFDvIQeibCmezSnk/q6iAfkdiQaJi4VzroCFrN20=
+golang.org/x/sys v0.32.0/go.mod h1:BJP2sWEmIv4KK5OTEluFJCKSidICx8ciO85XgH3Ak8k=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=

process.go

@@ -56,7 +56,7 @@ func NewProcess(extraEnv []string, args ...string) (*Process, error) {
 	}
 	p.cmd.Env = append(os.Environ(), extraEnv...)
 	tellCommandNotToSpawnShell(p.cmd)          // windows specific
-	tellCommandToStartOnNewProcessGroup(p.cmd) // linux specific
+	tellCommandToStartOnNewProcessGroup(p.cmd) // linux and macosx specific
 
 	// This is required because some tools detects if the program is running
 	// from terminal by looking at the stdin/out bindings.
@@ -67,6 +67,8 @@ func NewProcess(extraEnv []string, args ...string) (*Process, error) {
 
 // TellCommandNotToSpawnShell avoids that the specified Cmd display a small
 // command prompt while runnning on Windows. It has no effects on other OS.
+//
+// Deprecated: TellCommandNotToSpawnShell is now always applied by default, there is no need to call it anymore.
 func (p *Process) TellCommandNotToSpawnShell() {
 	tellCommandNotToSpawnShell(p.cmd)
 }

process_darwin.go

@@ -0,0 +1,62 @@
+//
+// This file is part of PathsHelper library.
+//
+// Copyright 2023 Arduino AG (http://www.arduino.cc/)
+//
+// PathsHelper library 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., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+//
+// As a special exception, you may use this file as part of a free software
+// library without restriction.  Specifically, if other files instantiate
+// templates or use macros or inline functions from this file, or you compile
+// this file and link it with other files to produce an executable, this
+// file does not by itself cause the resulting executable to be covered by
+// the GNU General Public License.  This exception does not however
+// invalidate any other reasons why the executable file might be covered by
+// the GNU General Public License.
+//
+
+package paths
+
+import (
+	"os/exec"
+	"syscall"
+)
+
+func tellCommandNotToSpawnShell(_ *exec.Cmd) {
+	// no op
+}
+
+func tellCommandToStartOnNewProcessGroup(oscmd *exec.Cmd) {
+	// https://groups.google.com/g/golang-nuts/c/XoQ3RhFBJl8
+
+	// Start the process in a new process group.
+	// This is needed to kill the process and its children
+	// if we need to kill the process.
+	if oscmd.SysProcAttr == nil {
+		oscmd.SysProcAttr = &syscall.SysProcAttr{}
+	}
+	oscmd.SysProcAttr.Setpgid = true
+}
+
+func kill(oscmd *exec.Cmd) error {
+	// https://groups.google.com/g/golang-nuts/c/XoQ3RhFBJl8
+
+	// Kill the process group
+	pgid, err := syscall.Getpgid(oscmd.Process.Pid)
+	if err != nil {
+		return err
+	}
+	return syscall.Kill(-pgid, syscall.SIGKILL)
+}

process_others.go

@@ -27,7 +27,7 @@
 // the GNU General Public License.
 //
 
-//go:build !windows && !linux
+//go:build !windows && !linux && !darwin
 
 package paths
 

process_windows.go

@@ -30,8 +30,12 @@
 package paths
 
 import (
+	"fmt"
 	"os/exec"
 	"syscall"
+	"unsafe"
+
+	"golang.org/x/sys/windows"
 )
 
 func tellCommandNotToSpawnShell(oscmd *exec.Cmd) {
@@ -46,5 +50,54 @@ func tellCommandToStartOnNewProcessGroup(_ *exec.Cmd) {
 }
 
 func kill(oscmd *exec.Cmd) error {
-	return oscmd.Process.Kill()
+	parentProcessMap, err := createParentProcessSnapshot()
+	if err != nil {
+		return err
+	}
+	return killPidTree(uint32(oscmd.Process.Pid), parentProcessMap)
+}
+
+// createParentProcessSnapshot returns a map that correlate a process
+// with its parent process: childPid -> parentPid
+func createParentProcessSnapshot() (map[uint32]uint32, error) {
+	// Inspired by: https://stackoverflow.com/a/36089871/1655275
+
+	// Make a snapshot of the current running processes
+	snapshot, err := windows.CreateToolhelp32Snapshot(windows.TH32CS_SNAPPROCESS, 0)
+	if err != nil {
+		return nil, fmt.Errorf("getting running processes snapshot: %w", err)
+	}
+	defer windows.CloseHandle(snapshot)
+
+	// Iterate the result and extract the parent-child relationship
+	processParentMap := map[uint32]uint32{}
+	var processEntry windows.ProcessEntry32
+	processEntry.Size = uint32(unsafe.Sizeof(processEntry))
+	hasData := (windows.Process32First(snapshot, &processEntry) == nil)
+	for hasData {
+		processParentMap[processEntry.ProcessID] = processEntry.ParentProcessID
+		hasData = (windows.Process32Next(snapshot, &processEntry) == nil)
+	}
+	return processParentMap, nil
+}
+
+func killPidTree(pid uint32, parentProcessMap map[uint32]uint32) error {
+	for childPid, parentPid := range parentProcessMap {
+		if parentPid == pid {
+			// Descend process tree
+			if err := killPidTree(childPid, parentProcessMap); err != nil {
+				return fmt.Errorf("error killing child process: %w", err)
+			}
+		}
+	}
+	return killPid(pid)
+}
+
+func killPid(pid uint32) error {
+	process, err := windows.OpenProcess(windows.PROCESS_ALL_ACCESS, false, pid)
+	if err != nil {
+		return fmt.Errorf("opening process for kill: %w", err)
+	}
+	defer windows.CloseHandle(process)
+	return windows.TerminateProcess(process, 128)
 }