"

 COPYRIGHT (c) 1988 by Claus Gittinger

              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.

"

Object subclass:#Smalltalk

	instanceVariableNames:''

	classVariableNames:'StartBlocks ImageStartBlocks ExitBlocks CachedClasses SystemPath

		StartupClass StartupSelector StartupArguments CommandLine

		CommandLineArguments CachedAbbreviations SilentLoading

		Initializing StandAlone LogDoits LoadBinaries RealSystemPath

		ResourcePath SourcePath BitmapPath BinaryPath FileInPath

		ImageStartTime ImageRestartTime DemoMode'

	poolDictionaries:''

	category:'System-Support'

!

!Smalltalk class methodsFor:'documentation'!

copyright

"

 COPYRIGHT (c) 1988 by Claus Gittinger

              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 is one of the central classes in the system;

    it provides all system-startup, shutdown and maintenance support.

    Also global variables are (conceptionally) kept here.

    As you will notice, this is NOT a Dictionary

     - my implementation of globals is totally different

       (due to the need to be able to access globals from c-code as well).

    However, it provides the known enumeration protocol.

    It may change to become a subclass of collection at some time ...

    [Instance variables:]

                                        none - all handling is done in the VM

    [Class variables:]

        StartBlocks     <Collection>    blocks to be executed in a separate process after

                                        everything has been initialized. These blocks will

                                        be deleted after execution and therefore not be

                                        executed after an image restart. Initial processes

                                        are usually started here.

        ImageStartBlocks 

                        <Collection>    blocks to be executed in a separate process after

                                        everything has been initialized. These blocks will be

                                        executed after an image restart.

        ExitBlocks      <Collection>    blocks to evaluate before system is

                                        left. Not currently used (GNU-ST compatibility).

        SystemPath      <Collection>    path to search for system files (sources, bitmaps etc)

                                        Set to a default here, but typically changed from some

                                        startup.rc file

        StartupClass    <Class>         

        StartupSelector <Symbol>        

        StartupArguments <Array>

                                        class and selector, where the system starts up

                                        (right after VM initialization)

                                        If an image is saved while this is nonNil, the image will come up

                                        there.

        CommandLineArguments <Array>    command line broken into words

        SilentLoading   <Boolean>       suppresses messages during fileIn and in compiler

                                        (can be set to true from a customized main)

        LogDoits        <Boolean>       if true, doits are also logged in the changes

                                        file. Default is false, since the changes file

                                        may become huge if every tiny doIt is saved there ...

        LoadBinaries    <Boolean>       if true, we attempt to load classes rom a binary

                                        file, if present. If false, this is always suppressed.

        ImageStartTime  <AbsoluteTime>  timestamp when this system was started the very first time

                                        (i.e. the time of the initial start without an image)

        ImageRestartTime

                        <AbsoluteTIme>  timestamp when this image was started

    strictly private classVariables (helpers):

        CachedClasses   <Collection>    known classes (cached for faster class enumeration)

        CachedAbbreviations

                        <Dictionary>    className to filename mappings

        SourcePath      <Collection>    cached names of really existing directories

        BitmapPath                      These are remembered, since in NFS systems,

        ResourcePath                    the time to lookup files may become long

        BinaryPath                      (especially, if some directories are on machines

        FileInPath                      which are not up ...). Therefore, the set of really

                                        existing directories is cached when the SystemPath

                                        is walked the first time.

    [author:]

        Claus Gittinger

"

! !

!Smalltalk class methodsFor:'initialization'!

initGlobalsFromEnvironment

    "setup globals from the shell-environment"

    |envString i langString terrString|

    "

     extract Language and LanguageTerritory from LANG variable.

     valid are for example: english_us / us_us / us

                            english / en_en / en

                            german / de_de / de

                            german_austria

    "

    Language := #english.

    LanguageTerritory := #us.

    envString := OperatingSystem getEnvironment:'LANG'.

    envString notNil ifTrue:[

        envString isEmpty ifFalse:[

            i := envString indexOf:$_.

            (i == 0) ifTrue:[

                langString := envString.

                terrString := envString

            ] ifFalse:[

                langString := envString copyTo:(i - 1).

                terrString := envString copyFrom:(i + 1)

            ].

            Language := langString asLowercase asSymbol.

            LanguageTerritory := terrString asLowercase asSymbol

        ]

    ].

    "

     Smalltalk initGlobalsFromEnvironment

    "

    "Modified: 22.2.1996 / 16:59:12 / cg"

!

initInterrupts

    "initialize interrupts"

    OperatingSystem enableUserInterrupts.

    OperatingSystem enableHardSignalInterrupts.

    OperatingSystem enableFpExceptionInterrupts.

    ObjectMemory userInterruptHandler:self.

    ObjectMemory signalInterruptHandler:self.

    ObjectMemory recursionInterruptHandler:self.

    "

     Smalltalk initInterrupts

    "

!

initStandardStreams

    "initialize some well-known streams"

    Stdout := NonPositionableExternalStream forStdout.

    Stderr := NonPositionableExternalStream forStderr.

    Stdin := NonPositionableExternalStream forStdin.

    Printer := PrinterStream.

    Transcript := Stderr

    "

     Smalltalk initStandardStreams

    "

!

initStandardTools

    "predefine some tools which we will need later

     - if the view-classes exist,

       they will redefine Inspector and Debugger for graphical interfaces"

    "redefine debug-tools, if view-classes exist"

    Display notNil ifTrue:[

        InspectorView notNil ifTrue:[

            Inspector := InspectorView

        ].

        DebugView notNil ifTrue:[

            Debugger := DebugView

        ].

        Display initialize

    ]

    "

     Smalltalk initStandardTools

    "

!

initSystemPath

    "setup path where system files are searched for.

     the default path is set to:

            .

            ..

            $HOME                    (if defined)

            $HOME/.smalltalk         (if defined & existing)

            $SMALLTALK_LIBDIR        (if defined & existing)

            $STX_LIBDIR              (if defined & existing)

            /usr/local/lib/smalltalk (if existing)

            /usr/lib/smalltalk       (if existing)

     of course, it is possible to add entries from the 'smalltalk.rc'

     startup file; add expressions such as:

            Smalltalk systemPath addFirst:'/foo/bar/baz'.

        or: 

            Smalltalk systemPath addLast:'/fee/foe/foo'.

    "

    |p homePath|

    SystemPath isNil ifTrue:[

        homePath := OperatingSystem getHomeDirectory.

        homePath isNil ifTrue:[

            homePath := '.'

        ].

        "

         the path is set to search files first locally

         - this allows private stuff to override global stuff

        "

        SystemPath := OrderedCollection new.

        SystemPath add:'.'.

        SystemPath add:'..'.

        SystemPath add:homePath.

        (OperatingSystem isDirectory:(p := homePath , '/.smalltalk')) ifTrue:[

            SystemPath add:p

        ].

        p := OperatingSystem getEnvironment:'SMALLTALK_LIBDIR'.

        p notNil ifTrue:[

            SystemPath add:p

        ].

        p := OperatingSystem getEnvironment:'STX_LIBDIR'.

        p notNil ifTrue:[

            SystemPath add:p

        ].

        (OperatingSystem isDirectory:'/usr/local/lib/smalltalk') ifTrue:[

            SystemPath add:'/usr/local/lib/smalltalk'

        ].

        (OperatingSystem isDirectory:'/usr/lib/smalltalk') ifTrue:[

            SystemPath add:'/usr/lib/smalltalk'

        ].

        self flushPathCaches

    ]

    "

     Smalltalk initSystemPath

     Smalltalk systemPath

    "

!

initUserPreferences

    "setup other stuff"

    LogDoits := false.

    LoadBinaries := false.

!

initializeModules

    "perform module specific initialization and

     send #initialize to all classes.

     Notice: this is not called when an image is restarted"

%{

    __init_registered_modules__(3);

    @global(DemoMode) = __getDemoMode() ? true : false;

%}

!

initializeSystem

    "initialize all other classes; setup dispatcher processes etc.

     This one is the first entry into the smalltalk world right after startup,

     ususally followed by Smalltalk>>start.

     Notice: 

        this is not called when an image is restarted; in this

        case the show starts in Smalltalk>>restart."

    SilentLoading := false.

    Initializing := true.

    "/

    "/ define low-level debugging tools - graphical classes are not prepared yet

    "/ to handle things. 

    "/ This will bring us into the MiniDebugger when an error occurs

    "/ during startup

    "/

    Inspector := MiniInspector.

    Debugger := MiniDebugger.

    "/

    "/ start catching SIGSEGV and SIGBUS

    "/

    OperatingSystem enableHardSignalInterrupts.

    self initGlobalsFromEnvironment.

    "/

    "/ sorry - there are some, which MUST be initialized before ..

    "/ reason: if any error happens during init, we need Signals, Stdout etc. to be there

    "/

    Object initialize.

    Signal initialize.

    ObjectMemory initialize.

    OperatingSystem initialize.

    Stream initialize.

    ExternalStream initialize.

    self initStandardStreams.    "/ setup Stdin, Stdout etc.

    "/

    "/ sorry, path must be set before ...

    "/ reason: some classes need it during initialize (they might need resources, bitmaps etc)

    "/

    self initSystemPath.

    "/

    "/ must init display here - some classes (Color, Form) need it during initialize

    "/"

    Workstation notNil ifTrue:[

        Workstation initialize

    ].

    Compiler := ByteCodeCompiler.

    Compiler isNil ifTrue:[

        "

         ByteCodeCompiler is not in the system (i.e. has not been linked in)

         this allows at least immediate evaluations for runtime systems without compiler

         NOTICE: a parser is always needed, otherwise we cannot read resource files etc.

        "

        Compiler := Parser

    ].

    "/

    "/ another one, to be initialized before others

    "/

    ProcessorScheduler initialize.

    "/

    "/ now, finally, initialize all other classes

    "/

    self initializeModules.

    ImageStartTime := AbsoluteTime now.

    Display notNil ifTrue:[

        Display initialize.

	Display initializeDeviceResources.

    ].

    self initInterrupts.

    self initUserPreferences.

    "/

    "/ give classes a chance to perform 2nd-level initialization

    "/ now, we are certain, that all other classes have been initialized

    "/ (especially: streams and signals can now be used)

    "/

    ObjectMemory changed:#initialized.

    "Modified: 8.1.1997 / 19:57:59 / cg"

    "Modified: 8.1.1997 / 19:58:12 / stefan"

!

isInitialized

    "this returns true, if the system is properly initialized;

     i.e. false during startup. Especially, the whole viewing stuff is

     not working correctly until initialized."

    ^ Initializing not

!

reinitStandardStreams

    "reinitialize some well-known streams.

     Tis must be done very early during startup, to allow for

     debug and trace messages to be output

     (otherwise, the file-descriptors are invalid)"

    Stdout reOpen. Stderr reOpen. Stdin reOpen.

! !

!Smalltalk class methodsFor:'accessing'!

at:aKey

    "retrieve the value stored under aKey, a symbol. 

     Return nil if not present 

     (this will be changed to trigger an error - better use #at:ifAbsent:)"

%{  /* NOCONTEXT */

    RETURN ( __GLOBAL_GET(aKey) );

%}

!

at:aKey ifAbsent:aBlock

    "retrieve the value stored at aKey.

     If there is nothing stored under this key, return the value of

     the evaluation of aBlock."

    (self includesKey:aKey) ifTrue:[

        ^ self at:aKey

    ].

    ^ aBlock value

    "

     Smalltalk at:#fooBar                       <- returns nil

     Smalltalk at:#fooBar ifAbsent:['sorry']    <- no error

    "

!

at:aKey put:aValue

    "store the argument aValue under aKey, a symbol.

     Return aValue (sigh)."

    |oldValue|

%{

    oldValue = __GLOBAL_SET(aKey, aValue, (OBJ *)0);

%}.

    CachedClasses notNil ifTrue:[

        oldValue isBehavior ifTrue:[

            oldValue name == aKey ifTrue:[

                CachedClasses remove:oldValue ifAbsent:[]

            ]

        ].

        aValue isBehavior ifTrue:[

"/            aValue isMeta ifTrue:[

"/                "/ this should not happen

"/                ('SMALLTALK: store a Metaclass: ' , aValue name , ' as ' , aKey) infoPrintCR.

"/            ].

            aValue name == aKey ifTrue:[

                CachedClasses add:aValue

            ]

        ].

    ].

    ^ aValue.

"/

"/%{  /* NOCONTEXT */

"/    (void) __GLOBAL_SET(aKey, aValue, (OBJ *)0);

"/%}.

"/    CachedClasses := nil.

"/    ^ aValue

    "Modified: 19.4.1996 / 11:31:49 / cg"

!

includesKey:aKey

    "return true, if the key is known"

%{  /* NOCONTEXT */

    RETURN ( __GLOBAL_KEYKNOWN(aKey) );

%}

!

keyAtValue:anObject

    "return the symbol under which anObject is stored - or nil"

    self keysDo:[:aKey |

        (self at:aKey) == anObject ifTrue:[^ aKey]

    ].

    ^ nil

    "Smalltalk keyAtValue:Object"

!