LibCompat: rewrite OSProcess to use LibUnix's #spawn:...

...rather than Mariano's `OSSubprocess` package. The problem is that
`OSSubProcess` reaping logic assumes that all processes are spawned by
it so it may (does) reap processes spawned by LibUnix.

This commit makes `OSProcess` compatibility class to use `LibUnix`
to avoid this problem and throw an error is OSSubProcess is loaded.

A proper fix would be to change `OSSubprocess` to only reap processes
it has spawned (see [1])

[1] pharo-contributions/OSSubprocess#76

src/LibCompat/OSProcess.class.st

@@ -8,7 +8,9 @@ Class {
 	#name : #OSProcess,
 	#superclass : #Object,
 	#instVars : [
-		'process'
+		'command',
+		'pid',
+		'status'
 	],
 	#category : #LibCompat
 }
@@ -23,31 +25,41 @@ OSProcess class >> command: aString [
 
 { #category : #accesing }
 OSProcess >> command: aString [
-	process shellCommand: aString. 
+	command := aString
 
 ]
 
 { #category : #initialization }
 OSProcess >> initialize [
-	process := OSSUnixSubprocess new.
+	(Smalltalk globals includesKey: #OSSUnixSubprocess) ifTrue:[
+		self error: 'OSSubProcess package loaded. OSSubProcess is incompatbile with LibCompat''s OSProcess implementation.'
+	].
 ]
 
 { #category : #testing }
 OSProcess >> isComplete [ 
-	^process isComplete
+	^status notNil
 ]
 
 { #category : #testing }
 OSProcess >> isRunning [ 
-	^process isRunning
+	^status isNil.
 ]
 
 { #category : #running }
 OSProcess >> startProcess [
-	process run
+	pid := Smalltalk os spawn: {'/bin/sh' . '-c' . command} stdin: Stdio stdin stdout: Stdio stdout stderr: Stdio stderr exit: [ :sts | status := sts. ].
 ]
 
 { #category : #'terminating child' }
 OSProcess >> terminate [
-	process terminate
+	pid isNil ifTrue:[
+		self error: 'Process not (yet) running'.
+		^ self.
+	].
+	status notNil ifTrue:[
+		self error: 'Process already terminated'.
+	].
+	LibC kill: pid _: 15"SIGTERM"
+
 ]

src/LibUnix/LibC.extension.st

@@ -77,6 +77,12 @@ LibC class >> ioctl: fd _: request _: param [
 	^ self ffiCall:#( int ioctl(int fd, long request, void* param) )  module: LibC  
 ]
 
+{ #category : #'*LibUnix' }
+LibC class >> kill: pid _: sig [
+	^ self ffiCall:#(int kill(int pid, int sig))  module: LibC
+
+]
+
 { #category : #'*LibUnix' }
 LibC class >> open: pathname _: flags [
 	^ self ffiCall: #(int open(char* pathname, int flags)) module: LibC

src/LibUnix/UnixProcessStatus.class.st

@@ -37,6 +37,20 @@ UnixProcessStatus >> pid: pidValue wstatus: wstatusValue [
 	wstatus := wstatusValue 
 ]
 
+{ #category : #printing }
+UnixProcessStatus >> printOn: aStream [
+	super printOn: aStream.
+	aStream nextPutAll: '(pid '.
+	pid printOn: aStream.
+	aStream nextPutAll: ', '.
+	aStream nextPutAll: self status.
+	aStream nextPutAll: ' '.
+	self code printOn: aStream.
+	aStream nextPutAll: ')'.
+
+
+]
+
 { #category : #accessing }
 UnixProcessStatus >> status [
 	"return status as a Symbol;