"

 COPYRIGHT (c) 1989 by Claus Gittinger

 COPYRIGHT (c) 2017 Jan Vrany

	      All Rights Reserved

 This software is furnished under a license and may be used

 only in accordance with the terms of that license and with the

 inclusion of the above copyright notice.   This software may not

 be provided or otherwise made available to, or used by, any

 other person.  No title to or ownership of the software is

 hereby transferred.

"

"{ Package: 'stx:libbasic' }"

"{ NameSpace: Smalltalk }"

ExternalStream subclass:#NonPositionableExternalStream

	instanceVariableNames:''

	classVariableNames:'StdInStream StdOutStream StdErrorStream'

	poolDictionaries:'TTYConstants'

	category:'Streams-External'

!

!NonPositionableExternalStream primitiveDefinitions!

%{

#ifndef _STDIO_H_INCLUDED_

# include <stdio.h>

# define _STDIO_H_INCLUDED_

#endif

#ifndef REMOVE_LATER

# define __win32_stdout()        stdout

# define __win32_stderr()        stderr

# define __win32_stdin()         stdin

#else

    extern FILE *__win32_stdin();

    extern FILE *__win32_stderr();

    extern FILE *__win32_stdout();

#endif

%}

! !

!NonPositionableExternalStream class methodsFor:'documentation'!

copyright

"

 COPYRIGHT (c) 1989 by Claus Gittinger

 COPYRIGHT (c) 2017 Jan Vrany

	      All Rights Reserved

 This software is furnished under a license and may be used

 only in accordance with the terms of that license and with the

 inclusion of the above copyright notice.   This software may not

 be provided or otherwise made available to, or used by, any

 other person.  No title to or ownership of the software is

 hereby transferred.

"

!

documentation

"

    This class provides common protocol for all non-positionable,

    external streams. Concrete subclasses are terminal streams, pipe streams,

    PrinterStreams, Sockets etc.

    There are three special instances of this class, representing stdin,

    stdout and stderr of the smalltalk/X process (see Unix manuals, if you

    don't know what those are used for). These special streams are bound to

    to globals Stdin, Stdout and Stderr at early initialization time

    (see Smalltalk>>initializeStandardStreams).

    The name of this class is a historical leftover - it should be called

    'TTYStream' or similar.

    [author:]

        Claus Gittinger

"

! !

!NonPositionableExternalStream class methodsFor:'instance creation'!

forStderr

    "{ Pragma: +optSpace }"

    "return a NonPositionableExternalStream object for writing to

     Unixes standard error output file descriptor"

    StdErrorStream isNil ifTrue:[

	StdErrorStream := self basicNew initializeForStderr

    ].

    ^ StdErrorStream

!

forStdin

    "{ Pragma: +optSpace }"

    "return a NonPositionableExternalStream object for reading from

     Unixes standard input file descriptor"

    StdInStream isNil ifTrue:[

	StdInStream := self basicNew initializeForStdin

    ].

    ^ StdInStream

!

forStdout

    "{ Pragma: +optSpace }"

    "return a NonPositionableExternalStream object for writing to

     Unixes standard output file descriptor"

    StdOutStream isNil ifTrue:[

	StdOutStream := self basicNew initializeForStdout

    ].

    ^ StdOutStream

!

makeBidirectionalPipe

    "return an array with two streams - the first one for reading,

     the second for writing.

     This is the higher level equivalent of OperatingSystem>>makeBidirectionalPipe

     (which returns an array of file-descriptors)."

    |pipe rs ws|

    pipe := OperatingSystem makeBidirectionalPipe.

    pipe isNil ifTrue:[

        "/ ok, maybe someone has forgotten to close a stream; enforce finalization and try again

        'makePipe: enforcing finalization to close any open streams' infoPrintCR.

        ObjectMemory garbageCollect; finalize.

        pipe := OperatingSystem makeBidirectionalPipe.

    ].

    pipe isNil ifTrue:[

        |errorNumber errorHolder|

        errorNumber := OperatingSystem lastErrorNumber.

        errorHolder := errorNumber.

        OpenError newException

            errorCode:errorNumber;

            osErrorHolder:errorHolder;

            raise.

    ].

    rs := NonPositionableExternalStream forFileDescriptor:(pipe at:1) mode:#readWrite buffered:false handleType:#pipeFilePointer.

    ws := NonPositionableExternalStream forFileDescriptor:(pipe at:2) mode:#readWrite buffered:false handleType:#pipeFilePointer.

    ^ Array with:rs with:ws

    "

     |pipe rs ws|

     pipe := NonPositionableExternalStream makeBidirectionalPipe.

     rs := pipe at:1.

     ws := pipe at:2.

     'read ...'.

     [

         1 to:10 do:[:i |

             Transcript showCR:rs nextLine

         ].

         rs close.

     ] forkAt:7.

     'write ...'.

     [

         1 to:10 do:[:i |

             ws nextPutAll:'hello world '; nextPutAll:i printString; cr

         ].

         ws close.

     ] fork.

    "

!

makePTYPair

    "return an array with two streams - the first one is the master,

     the second the slave of a ptym/ptys pair.

     This is much like a bidirectional pipe, but allows signals &

     control chars to be passed through the connection.

     This is needed to execute a shell in a view.

     This is the higher level equivalent of OperatingSystem>>makePTYPair

     (which returns an array of file-descriptors)."

    |ptyPair master slave|

    ptyPair := OperatingSystem makePTYPair.

    ptyPair notNil ifTrue:[

        master := NonPositionableExternalStream forReadWriteToFileDescriptor:(ptyPair at:1).

        master buffered:false.

        slave := NonPositionableExternalStream forReadWriteToFileDescriptor:(ptyPair at:2).

        slave buffered:false.

        ptyPair at:1 put:master.

        ptyPair at:2 put:slave.

        ^ ptyPair

    ].

    ^ nil

    "

     ExternalStream makePTYPair.

    "

    "Modified: 29.2.1996 / 18:28:36 / cg"

!

makePipe

    "return an array with two streams - the first one for reading,

     the second for writing.

     This is the higher level equivalent of OperatingSystem>>makePipe

     (which returns an array of file-descriptors)."

    |pipeArray rs ws|

    pipeArray := OperatingSystem makePipe.

    pipeArray isNil ifTrue:[

        "/ ok, maybe someone has forgotten to close a stream; enforce finalization and try again

        'makePipe: enforcing finalization to close any open streams' infoPrintCR.

        ObjectMemory garbageCollect; finalize.

        pipeArray := OperatingSystem makePipe.

    ].

    pipeArray isNil ifTrue:[

        |errorNumber errorHolder|

        errorNumber := OperatingSystem lastErrorNumber.

        errorHolder := errorNumber.

        OpenError newException

            errorCode:errorNumber;

            osErrorHolder:errorHolder;

            raise.

    ].

    rs := NonPositionableExternalStream forFileDescriptor:(pipeArray at:1) mode:#readonly buffered:false handleType:#pipeFilePointer.

    ws := NonPositionableExternalStream forFileDescriptor:(pipeArray at:2) mode:#writeonly buffered:false handleType:#pipeFilePointer.

    ^ Array with:rs with:ws

    "

     |pipe rs ws|

     pipe := NonPositionableExternalStream makePipe.

     rs := pipe at:1.

     ws := pipe at:2.

     'read ...'.

     [

         1 to:10 do:[:i |

             Transcript showCR:rs nextLine

         ].

         rs close.

     ] forkAt:7.

     'write ...'.

     [

         1 to:10 do:[:i |

             ws nextPutAll:'hello world '; nextPutAll:i printString; cr

         ].

         ws close.

     ] fork.

    "

    "Modified: 29.2.1996 / 18:28:36 / cg"

! !

!NonPositionableExternalStream methodsFor:'accessing'!

buffered:aBoolean

    "do not allow to change to buffered mode - ignore true here"

    aBoolean ifFalse:[

	super buffered:false.

    ].

!

setCommandString:dummyString

    "dummy for PipeStream compatibility"

    "Created: / 29-10-2018 / 18:06:44 / Claus Gittinger"

!

getTTYAttributes

    "Return (UNIX) TTY / PTY attributes for this stream as an instance of

     UnixTerminalAttributes. Throw an error if terminal attributes cannot 

     be retrieved (OS call fails, stream does  not refer to terminal or 

     opration is not supported by this operating system. 

     See tcgetattr()

    "

    ^ OperatingSystem getTTYAttributes: self fileDescriptor

    "

    Stdout ttyAttributes

    "

    "Created: / 30-05-2017 / 20:55:39 / Jan Vrany <jan.vrany@fit.cvut.cz>"

!

setTTYAttributes: aUnixTerminalAttributes

    "Set (UNIX) TTY / PTY attributes for this stream. Throw an error if 

     terminal attributes cannot be set (OS call fails, stream does  not 

     refer to terminal or operation is not supported by this operating 

     system. 

     See tcsetattr()

    "

    ^ OperatingSystem setTTYAttributes: self fileDescriptor to: aUnixTerminalAttributes withActions: TCSANOW

    "

    Stdout ttyAttributes

    "

    "Created: / 30-05-2017 / 20:57:25 / Jan Vrany <jan.vrany@fit.cvut.cz>"

! !

!NonPositionableExternalStream methodsFor:'error handling'!

positionError

    "{ Pragma: +optSpace }"

    "notify that this stream has no concept of a position"

    ^ PositionError raiseRequestWith:self

    "

     Stderr positionError

    "

!

writeError:errorNumber

    "report an error, that some write error occurred.

     Redefined to care for writeErrors on stdout and stderr,

     which happens under linux, if the console is closed while I am running.

     In this case, we ignore the error."

    ((self == Stderr) or:[self == Stdout]) ifTrue:[

        ^ self

    ].

    super writeError:errorNumber

! !

!NonPositionableExternalStream methodsFor:'initialization'!

initialize

    "non-positionable streams do not work well when buffered"

    super initialize.

    position := nil.    "I am not positionable (reading and writing simultaneously)"

    buffered := false.

! !

!NonPositionableExternalStream methodsFor:'non homogenous reading'!

nextBytes:count into:anObject startingAt:start

    "read the next count bytes into an object and return the number of

     bytes read or the number of bytes read, if EOF is encountered before.

     An exception is raised if the connection is broken.

     Redefined here to avoid blocking of ST/X when waiting for io.

     Instead only the calling thread will block"

    |remaining offset nRead|

    count == 0 ifTrue:[

	^ 0.

    ].

    remaining := count.

    offset := start.

    [

	nRead := self nextAvailableBytes:remaining into:anObject startingAt:offset.

	nRead == 0 ifTrue:[

	    "atEnd does a readWait"

	    self atEnd not.

	] ifFalse:[

	    remaining := remaining - nRead.

	    offset := offset + nRead.

	    remaining ~~ 0.

	]

    ] whileTrue.

    ^ count - remaining

!

nextInt16MSB:msbFlag

    "redefined to wait for data on pipes and sockets"

    |bytes nRead|

    bytes := ByteArray uninitializedNew:2.

    nRead := self nextBytes:2 into:bytes startingAt:1.

    nRead ~~ 2 ifTrue:[

        ^ self pastEndRead.

    ].

    ^ bytes signedInt16At:1 MSB:msbFlag.

!

nextInt32MSB:msbFlag

    "redefined to wait for data on pipes and sockets"

    |bytes nRead|

    bytes := ByteArray uninitializedNew:4.

    nRead := self nextBytes:4 into:bytes startingAt:1.

    nRead ~~ 4 ifTrue:[

        ^ self pastEndRead.

    ].

    ^ bytes signedInt32At:1 MSB:msbFlag.

!

nextInt64MSB:msbFlag

    "redefined to wait for data on pipes and sockets"

    |bytes nRead|

    bytes := ByteArray uninitializedNew:8.

    nRead := self nextBytes:8 into:bytes startingAt:1.

    nRead ~~ 8 ifTrue:[

        ^ self pastEndRead.

    ].

    ^ bytes signedInt64At:1 MSB:msbFlag.

!

nextUnsignedInt16MSB:msbFlag

    "redefined to wait for data on pipes and sockets"

    |bytes nRead|

    bytes := ByteArray uninitializedNew:2.

    nRead := self nextBytes:2 into:bytes startingAt:1.

    nRead ~~ 2 ifTrue:[

        ^ self pastEndRead.

    ].

    ^ bytes unsignedInt16At:1 MSB:msbFlag.

!

nextUnsignedInt32MSB:msbFlag

    "redefined to wait for data on pipes and sockets"

    |bytes nRead|

    bytes := ByteArray uninitializedNew:4.

    nRead := self nextBytes:4 into:bytes startingAt:1.

    nRead ~~ 4 ifTrue:[

        ^ self pastEndRead.

    ].

    ^ bytes unsignedInt32At:1 MSB:msbFlag.

!

nextUnsignedInt64MSB:msbFlag

    "redefined to wait for data on pipes and sockets"

    |bytes nRead|

    bytes := ByteArray uninitializedNew:8.

    nRead := self nextBytes:8 into:bytes startingAt:1.

    nRead ~~ 8 ifTrue:[

        ^ self pastEndRead.

    ].

    ^ bytes unsignedInt64At:1 MSB:msbFlag.

! !

!NonPositionableExternalStream methodsFor:'positioning'!

position

    position isNil ifTrue:[

        ^ self positionError.

    ].

    ^ position

!

position:newPosition

    (position isNil or:[newPosition < position]) ifTrue:[

        "there is no turning back"

        ^ self positionError

    ].

    self skip:newPosition - position.

!

skip:numberToSkip

    "skip count bytes/characters, return the receiver.

     Re-redefined since PositionableStream redefined it."

    "don't know how to unread ..."

    numberToSkip < 0 ifTrue:[

        ^ self positionError.

    ].