Add LibTTY providing access to the VM library for spawning a process connected to a pseudo-terminal

src/UnifiedFFI-Tests/LibTTYTest.class.st

@@ -0,0 +1,265 @@
+Class {
+	#name : 'LibTTYTest',
+	#superclass : 'TestCase',
+	#category : 'UnifiedFFI-Tests-Libraries',
+	#package : 'UnifiedFFI-Tests',
+	#tag : 'Libraries'
+}
+
+{ #category : 'asserting' }
+LibTTYTest >> assertProcessSpawnedWithFileDescriptor: fileDescriptor path: path arguments: arguments environment: environment input: inputString writes: expectedOutputString hasStatus: expectedStatus [
+
+	| pid status writeValue inputByteArray outputByteArray |
+
+	pid := -1.
+	status := nil.
+	outputByteArray :=
+		[
+			pid := LibTTY uniqueInstance ttySpawn: fileDescriptor path: path
+				arguments: arguments
+				environment: environment.
+			self deny: pid equals: -1.
+			inputString ifNotEmpty: [
+				inputByteArray := inputString utf8Encoded.
+				writeValue := LibC uniqueInstance write: fileDescriptor buffer: inputByteArray size: inputByteArray size.
+				self assert: writeValue equals: inputByteArray size ].
+			self readOutput: fileDescriptor
+		] ensure: [
+			LibC uniqueInstance close: fileDescriptor.
+			status := pid ~= -1 ifTrue: [ self getProcessStatus: pid ] ].
+	self assert: outputByteArray utf8Decoded equals: expectedOutputString.
+	self assert: status equals: expectedStatus.
+]
+
+{ #category : 'asserting' }
+LibTTYTest >> assertProcessSpawnedWithPseudoTerminalPath: path arguments: arguments environment: environment input: inputString writes: expectedOutputString hasStatus: expectedStatus [
+
+	self assertProcessSpawnedWithFileDescriptor: self openPseudoTerminal
+		path: path
+		arguments: arguments
+		environment: environment
+		input: inputString
+		writes: expectedOutputString
+		hasStatus: expectedStatus
+]
+
+{ #category : 'asserting' }
+LibTTYTest >> assertShellProcessWithCommand: shellCommand hasStatus: expectedStatus [
+
+	self assertShellProcessWithCommand: shellCommand writes: '' hasStatus: expectedStatus
+]
+
+{ #category : 'asserting' }
+LibTTYTest >> assertShellProcessWithCommand: shellCommand input: inputString writes: expectedOutputString hasStatus: expectedStatus [
+
+	self assertProcessSpawnedWithPseudoTerminalPath: '/bin/sh'
+		arguments: { '/bin/sh'. '-c'. shellCommand }
+		environment: Smalltalk os environment
+		input: inputString
+		writes: expectedOutputString
+		hasStatus: expectedStatus
+]
+
+{ #category : 'asserting' }
+LibTTYTest >> assertShellProcessWithCommand: shellCommand writes: expectedOutputString hasStatus: expectedStatus [
+
+	self assertShellProcessWithCommand: shellCommand input: '' writes: expectedOutputString hasStatus: expectedStatus
+]
+
+{ #category : 'private' }
+LibTTYTest >> flagOpenRDWR [
+
+	^ 2
+]
+
+{ #category : 'private' }
+LibTTYTest >> getProcessStatus: pid [
+
+	| statusArray |
+
+	statusArray := FFIExternalArray externalNewType: 'int' size: 1.
+	^ [
+		| pid2 statusInteger upper lower |
+		pid2 := LibC uniqueInstance waitpid: pid status: statusArray getHandle options: 0.
+		pid2 = pid ifFalse: [
+			Error signal: 'Could not get process status' ].
+		statusInteger := statusArray first.
+		upper := (statusInteger bitShift: -8) bitAnd: 16rFF.
+		lower := statusInteger bitAnd: 16r7F.
+		(lower > 0) ifTrue: [ 128 + lower ] ifFalse: [ upper ]
+	] ensure: [
+		statusArray free ]
+]
+
+{ #category : 'private' }
+LibTTYTest >> openPseudoTerminal [
+
+	| fdm |
+
+	(fdm := LibC uniqueInstance posix_openpt: self flagOpenRDWR) ~= -1 ifFalse: [
+		Error signal: 'Could not open pseudo-terminal device' ].
+	(LibC uniqueInstance grantpt: fdm) ~= -1 ifFalse: [
+		Error signal: 'Could not grant access to the slave pseudo-terminal device' ].
+	(LibC uniqueInstance unlockpt: fdm) ~= -1 ifFalse: [
+		Error signal: 'Could not unlock the slave pseudo-terminal device' ].
+	^ fdm
+]
+
+{ #category : 'private' }
+LibTTYTest >> performTest [
+
+	Smalltalk os isWindows ifTrue: [
+		self skip ].
+	super performTest
+]
+
+{ #category : 'private' }
+LibTTYTest >> readOutput: fdm [
+
+	^ ExternalAddress allocate: 1024 bytesDuring: [ :buffer |
+		ByteArray streamContents: [ :stream |
+			| count |
+			[ (count := LibC uniqueInstance read: fdm buffer: buffer size: buffer size) > 0 ] whileTrue: [
+				1 to: count do: [ :index |
+					stream nextPut: (buffer byteAt: index) ] ] ] ]
+]
+
+{ #category : 'tests' }
+LibTTYTest >> test1 [
+
+	| path fileDescriptorPseudoTerminal template fileDescriptorFile |
+
+	path := (#('/bin' '/usr/bin') collect: [ :element | element , '/true' ])
+		detect: [ :element | element asFileReference exists ].
+
+	fileDescriptorPseudoTerminal := self openPseudoTerminal.
+	self assertProcessSpawnedWithFileDescriptor: fileDescriptorPseudoTerminal
+		path: path
+		arguments: { path }
+		environment: Smalltalk os environment
+		input: ''
+		writes: ''
+		hasStatus: 0.
+
+	(template := ExternalAddress fromString: '/tmp/file.XXXXXX')
+		autoRelease.
+	fileDescriptorFile := LibC uniqueInstance mkstemp: template.
+	self deny: fileDescriptorFile equals: -1.
+	[
+		self assertProcessSpawnedWithFileDescriptor: fileDescriptorFile
+			path: path
+			arguments: { path }
+			environment: Smalltalk os environment
+			input: ''
+			writes: ''
+			hasStatus: 127
+	] ensure: [
+		template utf8StringFromCString asFileReference delete ].
+]
+
+{ #category : 'tests' }
+LibTTYTest >> test2 [
+
+	self assertProcessSpawnedWithPseudoTerminalPath: '/bin/echo'
+		arguments: #('/bin/echo' 'Argument1' 'Argument2' 'Argument3')
+		environment: Smalltalk os environment
+		input: ''
+		writes: 'Argument1 Argument2 Argument3' , String crlf
+		hasStatus: 0.
+
+	self assertProcessSpawnedWithPseudoTerminalPath: '/bin/echo'
+		arguments: #('/bin/echo' 'ĀĂĄ')
+		environment: Smalltalk os environment
+		input: ''
+		writes: 'ĀĂĄ' , String crlf
+		hasStatus: 0.
+
+	self assertProcessSpawnedWithPseudoTerminalPath: '/usr/bin/env'
+		arguments: #('/usr/bin/env')
+		environment: (OrderedDictionary with: 'VAR1' -> 'value1' with: 'VAR2' -> 'value2' with: 'VAR3' -> 'value3')
+		input: ''
+		writes: (String crlf join: #('VAR1=value1' 'VAR2=value2' 'VAR3=value3' ''))
+		hasStatus: 0.
+
+	self assertProcessSpawnedWithPseudoTerminalPath: '/usr/bin/env'
+		arguments: #('/usr/bin/env')
+		environment: (OrderedDictionary with: 'VAR' -> 'ĀĂĄ')
+		input: ''
+		writes: (String crlf join: #('VAR=ĀĂĄ' ''))
+		hasStatus: 0.
+
+	self assertProcessSpawnedWithPseudoTerminalPath: '/usr/bin/head'
+		arguments: #('/usr/bin/head' '-n' '2')
+		environment: Smalltalk os environment
+		input: (String lf join: #('Line1' 'Line2' 'Line3' ''))
+		writes: (String crlf join: #('Line1' 'Line2' 'Line3' 'Line1' 'Line2' ''))
+		hasStatus: 0.
+
+	self assertProcessSpawnedWithPseudoTerminalPath: '/bin/doesnotexist'
+		arguments: #('/bin/doesnotexist')
+		environment: Smalltalk os environment
+		input: ''
+		writes: 'Error in tty_spawn at execve(path, argv, envp): No such file or directory' , String crlf
+		hasStatus: 127.
+]
+
+{ #category : 'tests' }
+LibTTYTest >> test3 [
+
+	| formatDictionary echoesControlCharacters |
+
+	self assertShellProcessWithCommand: 'exit 42'
+		input: ''
+		writes: ''
+		hasStatus: 42.
+
+	formatDictionary := Dictionary <- {
+		'lf' -> Character lf.
+		'crlf' -> String crlf.
+		'end' -> Character end.
+		'bs' -> Character backspace }.
+	echoesControlCharacters := OSPlatform current isMacOSX.
+	self assertShellProcessWithCommand: 'tail -n 1'
+		input: ('Line 1{lf}Line 2{lf}{end}' format: formatDictionary)
+		writes: ('Line 1{crlf}Line 2{crlf}{echoedend}Line 2{crlf}' format: formatDictionary ,
+			(Dictionary with: 'echoedend' ->
+				(echoesControlCharacters ifTrue: [ '^D{bs}{bs}' format: formatDictionary ] ifFalse: [ '' ])))
+		hasStatus: 0.
+]
+
+{ #category : 'tests' }
+LibTTYTest >> test4 [
+
+	self assertShellProcessWithCommand: 'printf FOO'
+		writes: 'FOO'
+		hasStatus: 0.
+	self assertShellProcessWithCommand: 'printf BAR 1>&2'
+		writes: 'BAR'
+		hasStatus: 0.
+	self assertShellProcessWithCommand: 'exit 123'
+		writes: ''
+		hasStatus: 123.
+]
+
+{ #category : 'tests' }
+LibTTYTest >> test5 [
+
+	self assertShellProcessWithCommand: 'true'
+		hasStatus: 0.
+	self assertShellProcessWithCommand: '! true'
+		hasStatus: 1.
+	self assertShellProcessWithCommand: 'test -t 0'
+		hasStatus: 0.
+	self assertShellProcessWithCommand: 'test -t 0 </dev/zero'
+		hasStatus: 1.
+	self assertShellProcessWithCommand: 'test -t 1'
+		hasStatus: 0.
+	self assertShellProcessWithCommand: 'test -t 1 >/dev/null'
+		hasStatus: 1.
+	self assertShellProcessWithCommand: 'test -t 2'
+		hasStatus: 0.
+	self assertShellProcessWithCommand: 'test -t 2 2>/dev/null'
+		hasStatus: 1.
+	self assertShellProcessWithCommand: 'kill -s KILL $$'
+		hasStatus: 128 + 9.
+]

src/UnifiedFFI/LibC.class.st

@@ -6,6 +6,9 @@ Under windows I provide similar functionality through the functions defined in m
 Class {
 	#name : 'LibC',
 	#superclass : 'FFILibrary',
+	#pools : [
+		'LibCTypes'
+	],
 	#category : 'UnifiedFFI-Libraries',
 	#package : 'UnifiedFFI',
 	#tag : 'Libraries'
@@ -57,11 +60,17 @@ LibC class >> system: command [
 	^ self uniqueInstance system: command
 ]
 
+{ #category : 'api - input/output' }
+LibC >> close: fildes [
+
+	^ self ffiCall: #(int close(int fildes))
+]
+
 { #category : 'api - processes' }
 LibC >> currentProcessId [
 	"Returns the process identifier (PID) of the calling process."
 
-	 ^self ffiCall: #(int getpid(void))
+	 ^self ffiCall: #(pid_t getpid(void))
 ]
 
 { #category : 'api - accessing' }
@@ -75,7 +84,13 @@ LibC >> fgetc: stream [
 LibC >> getpid [
 	"Get PID of current process."
 
-	 ^self ffiCall: #(int getpid(void))
+	 ^self ffiCall: #(pid_t getpid(void))
+]
+
+{ #category : 'api - pseudo-terminals' }
+LibC >> grantpt: fildes [
+
+	^ self ffiCall: #(int grantpt(int fildes))
 ]
 
 { #category : 'private - accessing' }
@@ -89,11 +104,17 @@ LibC >> memCopy: src to: dest size: n [
 		ffiCall: #(#void #* #memcpy #(#void #* #dest #, #const #void #* #src #, #size_t #n))
 ]
 
+{ #category : 'api - misc' }
+LibC >> mkstemp: template [
+
+	^ self ffiCall: #(int mkstemp #(char* template))
+]
+
 { #category : 'api - processes' }
 LibC >> parentProcessId [
 	"Returns the process ID of the parent of the calling process."
 
-	 ^self ffiCall: #(int getppid(void))
+	 ^self ffiCall: #(pid_t getppid(void))
 ]
 
 { #category : 'api - piping' }
@@ -114,6 +135,18 @@ LibC >> pipeClose: stream [
 							ifFalse: [ #(int* pclose(void* stream)) ])
 ]
 
+{ #category : 'api - pseudo-terminals' }
+LibC >> posix_openpt: oflag [
+
+	^ self ffiCall: #(int posix_openpt(int oflag))
+]
+
+{ #category : 'api - input/output' }
+LibC >> read: fildes buffer: buf size: nbyte [
+
+	^ self ffiCall: #(ssize_t read(int fildes, void* buf, size_t nbyte))
+]
+
 { #category : 'process actions' }
 LibC >> resultOfCommand: cmd [
 	|file last s |
@@ -142,8 +175,26 @@ LibC >> unixLibraryName [
 	^ 'libc.so.6'
 ]
 
+{ #category : 'api - pseudo-terminals' }
+LibC >> unlockpt: fildes [
+
+	^ self ffiCall: #(int unlockpt(int fildes))
+]
+
+{ #category : 'api - processes' }
+LibC >> waitpid: pid status: stat_loc options: options [
+
+	^ self ffiCall: #(pid_t waitpid(pid_t pid, int* stat_loc, int options))
+]
+
 { #category : 'private - accessing' }
 LibC >> win32LibraryName [
 	"While this is not a 'libc' properly, msvcrt has the functions we are defining here"
 	^ 'msvcrt.dll'
 ]
+
+{ #category : 'api - input/output' }
+LibC >> write: fildes buffer: buf size: nbyte [
+
+	^ self ffiCall: #(ssize_t write(int fildes, const void* buf, size_t nbyte))
+]

src/UnifiedFFI/LibCTypes.class.st

@@ -0,0 +1,21 @@
+"
+LibCTypes defines types used in `LibC`.
+"
+Class {
+	#name : 'LibCTypes',
+	#superclass : 'SharedPool',
+	#classVars : [
+		'pid_t',
+		'ssize_t'
+	],
+	#category : 'UnifiedFFI-Libraries',
+	#package : 'UnifiedFFI',
+	#tag : 'Libraries'
+}
+
+{ #category : 'class initialization' }
+LibCTypes class >> initialize [
+
+	ssize_t := #long.
+	pid_t := #int.
+]