File:  [gforth] / gforth / kernel / int.fs
Revision 1.118: download - view: text, annotated - select for diffs
Sat Jan 22 21:06:04 2005 UTC (19 years, 2 months ago) by anton
Branches: MAIN
CVS tags: HEAD
preparation for gcc PR 15242 workaround
minor changes

    1: \ definitions needed for interpreter only
    2: 
    3: \ Copyright (C) 1995-2000,2004 Free Software Foundation, Inc.
    4: 
    5: \ This file is part of Gforth.
    6: 
    7: \ Gforth is free software; you can redistribute it and/or
    8: \ modify it under the terms of the GNU General Public License
    9: \ as published by the Free Software Foundation; either version 2
   10: \ of the License, or (at your option) any later version.
   11: 
   12: \ This program is distributed in the hope that it will be useful,
   13: \ but WITHOUT ANY WARRANTY; without even the implied warranty of
   14: \ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   15: \ GNU General Public License for more details.
   16: 
   17: \ You should have received a copy of the GNU General Public License
   18: \ along with this program; if not, write to the Free Software
   19: \ Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111, USA.
   20: 
   21: \ \ Revision-Log
   22: 
   23: \       put in seperate file				14sep97jaw 
   24: 
   25: \ \ input stream primitives                       	23feb93py
   26: 
   27: require ./basics.fs 	\ bounds decimal hex ...
   28: require ./io.fs		\ type ...
   29: require ./nio.fs	\ . <# ...
   30: require ./errore.fs	\ .error ...
   31: require kernel/version.fs	\ version-string
   32: require ./../chains.fs
   33: 
   34: has? new-input 0= [IF]
   35: : tib ( -- c-addr ) \ core-ext t-i-b
   36:     \G @i{c-addr} is the address of the Terminal Input Buffer.
   37:     \G OBSOLESCENT: @code{source} superceeds the function of this word.
   38:     >tib @ ;
   39: 
   40: Defer source ( -- c-addr u ) \ core
   41: \ used by dodefer:, must be defer
   42: \G @i{c-addr} is the address of the input buffer and @i{u} is the
   43: \G number of characters in it.
   44: 
   45: : (source) ( -- c-addr u )
   46:     tib #tib @ ;
   47: ' (source) IS source
   48: [THEN]
   49: 
   50: : (word) ( addr1 n1 char -- addr2 n2 )
   51:   dup >r skip 2dup r> scan  nip - ;
   52: 
   53: \ (word) should fold white spaces
   54: \ this is what (parse-white) does
   55: 
   56: \ word parse                                           23feb93py
   57: 
   58: : sword  ( char -- addr len ) \ gforth s-word
   59:     \G Parses like @code{word}, but the output is like @code{parse} output.
   60:     \G @xref{core-idef}.
   61:   \ this word was called PARSE-WORD until 0.3.0, but Open Firmware and
   62:   \ dpANS6 A.6.2.2008 have a word with that name that behaves
   63:   \ differently (like NAME).
   64:   source 2dup >r >r >in @ over min /string
   65:   rot dup bl = IF  drop (parse-white)  ELSE  (word)  THEN
   66:   2dup + r> - 1+ r> min >in ! ;
   67: 
   68: : word   ( char "<chars>ccc<char>-- c-addr ) \ core
   69:     \G Skip leading delimiters. Parse @i{ccc}, delimited by
   70:     \G @i{char}, in the parse area. @i{c-addr} is the address of a
   71:     \G transient region containing the parsed string in
   72:     \G counted-string format. If the parse area was empty or
   73:     \G contained no characters other than delimiters, the resulting
   74:     \G string has zero length. A program may replace characters within
   75:     \G the counted string. OBSOLESCENT: the counted string has a
   76:     \G trailing space that is not included in its length.
   77:     sword here place  bl here count + c!  here ;
   78: 
   79: : parse    ( char "ccc<char>" -- c-addr u ) \ core-ext
   80: \G Parse @i{ccc}, delimited by @i{char}, in the parse
   81: \G area. @i{c-addr u} specifies the parsed string within the
   82: \G parse area. If the parse area was empty, @i{u} is 0.
   83:     >r  source  >in @ over min /string  over  swap r>  scan >r
   84:     over - dup r> IF 1+ THEN  >in +! ;
   85: 
   86: \ name                                                 13feb93py
   87: 
   88: [IFUNDEF] (name) \ name might be a primitive
   89: 
   90: : (name) ( -- c-addr count ) \ gforth
   91:     source 2dup >r >r >in @ /string (parse-white)
   92:     2dup + r> - 1+ r> min >in ! ;
   93: \    name count ;
   94: [THEN]
   95: 
   96: : name-too-short? ( c-addr u -- c-addr u )
   97:     dup 0= -&16 and throw ;
   98: 
   99: : name-too-long? ( c-addr u -- c-addr u )
  100:     dup lcount-mask u> -&19 and throw ;
  101: 
  102: \ \ Number parsing					23feb93py
  103: 
  104: \ number? number                                       23feb93py
  105: 
  106: hex
  107: const Create bases   0A , 10 ,   2 ,   0A ,
  108: \                    10   16     2     10
  109: 
  110: \ !! protect BASE saving wrapper against exceptions
  111: : getbase ( addr u -- addr' u' )
  112:     2dup s" 0x" string-prefix? >r
  113:     2dup s" 0X" string-prefix? r> or
  114:     base @ &34 < and if
  115: 	hex 2 /string
  116:     endif
  117:     over c@ [char] # - dup 4 u<
  118:     IF
  119: 	cells bases + @ base ! 1 /string
  120:     ELSE
  121: 	drop
  122:     THEN ;
  123: 
  124: : sign? ( addr u -- addr u flag )
  125:     over c@ [char] - =  dup >r
  126:     IF
  127: 	1 /string
  128:     THEN
  129:     r> ;
  130: 
  131: : s'>unumber? ( addr u -- ud flag )
  132:     \ convert string "C" or "C'" to character code
  133:     dup 0= if
  134: 	false exit
  135:     endif
  136:     x@+/string 0 s" '" 2rot string-prefix? ;
  137: 
  138: : s>unumber? ( addr u -- ud flag )
  139:     over c@ '' = if
  140: 	1 /string s'>unumber? exit
  141:     endif
  142:     base @ >r  dpl on  getbase
  143:     0. 2swap
  144:     BEGIN ( d addr len )
  145: 	dup >r >number dup
  146:     WHILE \ there are characters left
  147: 	dup r> -
  148:     WHILE \ the last >number parsed something
  149: 	dup 1- dpl ! over c@ [char] . =
  150:     WHILE \ the current char is '.'
  151: 	1 /string
  152:     REPEAT  THEN \ there are unparseable characters left
  153: 	2drop false
  154:     ELSE
  155: 	rdrop 2drop true
  156:     THEN
  157:     r> base ! ;
  158: 
  159: \ ouch, this is complicated; there must be a simpler way - anton
  160: : s>number? ( addr len -- d f )
  161:     \ converts string addr len into d, flag indicates success
  162:     sign? >r
  163:     s>unumber?
  164:     0= IF
  165:         rdrop false
  166:     ELSE \ no characters left, all ok
  167: 	r>
  168: 	IF
  169: 	    dnegate
  170: 	THEN
  171: 	true
  172:     THEN ;
  173: 
  174: : s>number ( addr len -- d )
  175:     \ don't use this, there is no way to tell success
  176:     s>number? drop ;
  177: 
  178: : snumber? ( c-addr u -- 0 / n -1 / d 0> )
  179:     s>number? 0=
  180:     IF
  181: 	2drop false  EXIT
  182:     THEN
  183:     dpl @ dup 0< IF
  184: 	nip
  185:     ELSE
  186: 	1+
  187:     THEN ;
  188: 
  189: : number? ( string -- string 0 / n -1 / d 0> )
  190:     dup >r count snumber? dup if
  191: 	rdrop
  192:     else
  193: 	r> swap
  194:     then ;
  195: 
  196: : number ( string -- d )
  197:     number? ?dup 0= abort" ?"  0<
  198:     IF
  199: 	s>d
  200:     THEN ;
  201: 
  202: \ \ Comments ( \ \G
  203: 
  204: : ( ( compilation 'ccc<close-paren>' -- ; run-time -- ) \ thisone- core,file	paren
  205:     \G ** this will not get annotated. The alias in glocals.fs will instead **
  206:     \G It does not work to use "wordset-" prefix since this file is glossed
  207:     \G by cross.fs which doesn't have the same functionalty as makedoc.fs
  208:     [char] ) parse 2drop ; immediate
  209: 
  210: : \ ( compilation 'ccc<newline>' -- ; run-time -- ) \ thisone- core-ext,block-ext backslash
  211:     \G ** this will not get annotated. The alias in glocals.fs will instead ** 
  212:     \G It does not work to use "wordset-" prefix since this file is glossed
  213:     \G by cross.fs which doesn't have the same functionalty as makedoc.fs
  214:     [ has? file [IF] ]
  215:     blk @
  216:     IF
  217: 	>in @ c/l / 1+ c/l * >in !
  218: 	EXIT
  219:     THEN
  220:     [ [THEN] ]
  221:     source >in ! drop ; immediate
  222: 
  223: : \G ( compilation 'ccc<newline>' -- ; run-time -- ) \ gforth backslash-gee
  224:     \G Equivalent to @code{\} but used as a tag to annotate definition
  225:     \G comments into documentation.
  226:     POSTPONE \ ; immediate
  227: 
  228: \ \ object oriented search list                         17mar93py
  229: 
  230: \ word list structure:
  231: 
  232: struct
  233:   cell% field find-method   \ xt: ( c_addr u wid -- nt )
  234:   cell% field reveal-method \ xt: ( nt wid -- ) \ used by dofield:, must be field
  235:   cell% field rehash-method \ xt: ( wid -- )	   \ re-initializes a "search-data" (hashtables)
  236:   cell% field hash-method   \ xt: ( wid -- )    \ initializes ""
  237: \   \ !! what else
  238: end-struct wordlist-map-struct
  239: 
  240: struct
  241:   cell% field wordlist-map \ pointer to a wordlist-map-struct
  242:   cell% field wordlist-id \ linked list of words (for WORDS etc.)
  243:   cell% field wordlist-link \ link field to other wordlists
  244:   cell% field wordlist-extend \ wordlist extensions (eg bucket offset)
  245: end-struct wordlist-struct
  246: 
  247: has? f83headerstring [IF]
  248: : f83find      ( addr len wordlist -- nt / false )
  249:     wordlist-id @ (f83find) ;
  250: [ELSE]
  251: : f83find      ( addr len wordlist -- nt / false )
  252:     wordlist-id @ (listlfind) ;
  253: [THEN]
  254: 
  255: : initvoc		( wid -- )
  256:   dup wordlist-map @ hash-method perform ;
  257: 
  258: \ Search list table: find reveal
  259: Create f83search ( -- wordlist-map )
  260:     ' f83find A,  ' drop A,  ' drop A, ' drop A,
  261: 
  262: here G f83search T A, NIL A, NIL A, NIL A,
  263: AValue forth-wordlist \ variable, will be redefined by search.fs
  264: 
  265: AVariable lookup       	forth-wordlist lookup !
  266: \ !! last is user and lookup?! jaw
  267: AVariable current ( -- addr ) \ gforth
  268: \G @code{Variable} -- holds the @i{wid} of the compilation word list.
  269: AVariable voclink	forth-wordlist wordlist-link voclink !
  270: \ lookup AValue context ( -- addr ) \ gforth
  271: Defer context ( -- addr ) \ gforth
  272: \G @code{context} @code{@@} is the @i{wid} of the word list at the
  273: \G top of the search order.
  274: 
  275: ' lookup is context
  276: forth-wordlist current !
  277: 
  278: \ \ header, finding, ticks                              17dec92py
  279: 
  280: \ The constants are defined as 32 bits, but then erased
  281: \ and overwritten by the right ones
  282: 
  283: has? f83headerstring [IF]
  284:     \ to save space, Gforth EC limits words to 31 characters
  285:     $80 constant alias-mask
  286:     $40 constant immediate-mask
  287:     $20 constant restrict-mask
  288:     $1f constant lcount-mask
  289: [ELSE]    
  290: $80000000 constant alias-mask
  291: 1 bits/char 1 - lshift
  292: -1 cells allot  bigendian [IF]   c, 0 1 cells 1- times
  293:                           [ELSE] 0 1 cells 1- times c, [THEN]
  294: $40000000 constant immediate-mask
  295: 1 bits/char 2 - lshift
  296: -1 cells allot  bigendian [IF]   c, 0 1 cells 1- times
  297:                           [ELSE] 0 1 cells 1- times c, [THEN]
  298: $20000000 constant restrict-mask
  299: 1 bits/char 3 - lshift
  300: -1 cells allot  bigendian [IF]   c, 0 1 cells 1- times
  301:                           [ELSE] 0 1 cells 1- times c, [THEN]
  302: $1fffffff constant lcount-mask
  303: 1 bits/char 3 - lshift 1 -
  304: -1 cells allot  bigendian [IF]   c, -1 1 cells 1- times
  305:                           [ELSE] -1 1 cells 1- times c, [THEN]
  306: [THEN]
  307: 
  308: \ higher level parts of find
  309: 
  310: : flag-sign ( f -- 1|-1 )
  311:     \ true becomes 1, false -1
  312:     0= 2* 1+ ;
  313: 
  314: : ticking-compile-only-error ( ... -- )
  315:     -&2048 throw ;
  316: 
  317: : compile-only-error ( ... -- )
  318:     -&14 throw ;
  319: 
  320: : (cfa>int) ( cfa -- xt )
  321: [ has? compiler [IF] ]
  322:     dup interpret/compile?
  323:     if
  324: 	interpret/compile-int @
  325:     then 
  326: [ [THEN] ] ;
  327: 
  328: : (x>int) ( cfa w -- xt )
  329:     \ get interpretation semantics of name
  330:     restrict-mask and
  331:     if
  332: 	drop ['] compile-only-error
  333:     else
  334: 	(cfa>int)
  335:     then ;
  336: 
  337: has? f83headerstring [IF]
  338: : name>string ( nt -- addr count ) \ gforth     head-to-string
  339:     \g @i{addr count} is the name of the word represented by @i{nt}.
  340:     cell+ count lcount-mask and ;
  341: 
  342: : ((name>))  ( nfa -- cfa )
  343:     name>string + cfaligned ;
  344: 
  345: : (name>x) ( nfa -- cfa w )
  346:     \ cfa is an intermediate cfa and w is the flags cell of nfa
  347:     dup ((name>))
  348:     swap cell+ c@ dup alias-mask and 0=
  349:     IF
  350:         swap @ swap
  351:     THEN ;
  352: [ELSE]
  353: : name>string ( nt -- addr count ) \ gforth     head-to-string
  354:     \g @i{addr count} is the name of the word represented by @i{nt}.
  355:     cell+ dup cell+ swap @ lcount-mask and ;
  356: 
  357: : ((name>))  ( nfa -- cfa )
  358:     name>string + cfaligned ;
  359: 
  360: : (name>x) ( nfa -- cfa w )
  361:     \ cfa is an intermediate cfa and w is the flags cell of nfa
  362:     dup ((name>))
  363:     swap cell+ @ dup alias-mask and 0=
  364:     IF
  365:         swap @ swap
  366:     THEN ;
  367: [THEN]
  368: 
  369: : name>int ( nt -- xt ) \ gforth
  370:     \G @i{xt} represents the interpretation semantics of the word
  371:     \G @i{nt}. If @i{nt} has no interpretation semantics (i.e. is
  372:     \G @code{compile-only}), @i{xt} is the execution token for
  373:     \G @code{ticking-compile-only-error}, which performs @code{-2048 throw}.
  374:     (name>x) (x>int) ;
  375: 
  376: : name?int ( nt -- xt ) \ gforth
  377:     \G Like @code{name>int}, but perform @code{-2048 throw} if @i{nt}
  378:     \G has no interpretation semantics.
  379:     (name>x) restrict-mask and
  380:     if
  381: 	ticking-compile-only-error \ does not return
  382:     then
  383:     (cfa>int) ;
  384: 
  385: : (name>comp) ( nt -- w +-1 ) \ gforth
  386:     \G @i{w xt} is the compilation token for the word @i{nt}.
  387:     (name>x) >r 
  388: [ has? compiler [IF] ]
  389:     dup interpret/compile?
  390:     if
  391:         interpret/compile-comp @
  392:     then 
  393: [ [THEN] ]
  394:     r> immediate-mask and flag-sign
  395:     ;
  396: 
  397: : (name>intn) ( nfa -- xt +-1 )
  398:     (name>x) tuck (x>int) ( w xt )
  399:     swap immediate-mask and flag-sign ;
  400: 
  401: const Create ???  0 , 3 , char ? c, char ? c, char ? c,
  402: \ ??? is used by dovar:, must be created/:dovar
  403: 
  404: [IFDEF] forthstart
  405: \ if we have a forthstart we can define head? with it
  406: \ otherwise leave out the head? check
  407: 
  408: : head? ( addr -- f )
  409: \G heuristic check whether addr is a name token; may deliver false
  410: \G positives; addr must be a valid address; returns 1 for
  411: \G particularly unsafe positives
  412:     \ we follow the link fields and check for plausibility; two
  413:     \ iterations should catch most false addresses: on the first
  414:     \ iteration, we may get an xt, on the second a code address (or
  415:     \ some code), which is typically not in the dictionary.
  416:     \ we added a third iteration for working with code and ;code words.
  417:     3 0 do
  418: 	dup dup aligned <> if \ protect @ against unaligned accesses
  419: 	    drop false unloop exit
  420: 	then
  421: 	dup @ dup
  422: 	if ( addr addr1 )
  423: 	    dup rot forthstart within
  424: 	    if \ addr1 is outside forthstart..addr, not a head
  425: 		drop false unloop exit
  426: 	    then ( addr1 )
  427: 	else \ 0 in the link field, no further checks
  428: 	    2drop 1 unloop exit \ this is very unsure, so return 1
  429: 	then
  430:     loop
  431:     \ in dubio pro:
  432:     drop true ;
  433: 
  434: : >head-noprim ( cfa -- nt ) \ gforth  to-head-noprim
  435:     \ also heuristic
  436:     dup forthstart - max-name-length @ float+ cell+ min cell max cell ?do ( cfa )
  437: 	dup i - dup @ [ alias-mask lcount-mask or ] literal
  438: 	[ 1 bits/char 3 - lshift 1 - 1 bits/char 1 - lshift or
  439: 	-1 cells allot bigendian [IF]   c, -1 1 cells 1- times
  440: 	[ELSE] -1 1 cells 1- times c, [THEN] ]
  441: 	and ( cfa len|alias )
  442: 	swap + cell+ cfaligned over alias-mask + =
  443: 	if ( cfa )
  444: 	    dup i - cell - dup head?
  445: 	    if
  446: 		nip unloop exit
  447: 	    then
  448: 	    drop
  449: 	then
  450: 	cell +loop
  451:     drop ??? ( wouldn't 0 be better? ) ;
  452: 
  453: [ELSE]
  454: 
  455: : >head-noprim ( cfa -- nt ) \ gforth  to-head-noprim
  456:     $25 cell do ( cfa )
  457: 	dup i - dup @ [ alias-mask lcount-mask or ] literal
  458: 	[ 1 bits/char 3 - lshift 1 - 1 bits/char 1 - lshift or
  459: 	-1 cells allot bigendian [IF]   c, -1 1 cells 1- times
  460: 	[ELSE] -1 1 cells 1- times c, [THEN] ]
  461: 	and ( cfa len|alias )
  462: 	swap + cell + cfaligned over alias-mask + =
  463: 	if ( cfa ) i - cell - unloop exit
  464: 	then
  465: 	cell +loop
  466:     drop ??? ( wouldn't 0 be better? ) ;
  467: 
  468: [THEN]
  469: 
  470: cell% 2* 0 0 field >body ( xt -- a_addr ) \ core
  471: \G Get the address of the body of the word represented by @i{xt} (the
  472: \G address of the word's data field).
  473: drop drop
  474: 
  475: cell% -2 * 0 0 field body> ( xt -- a_addr )
  476:     drop drop
  477: 
  478: has? standardthreading has? compiler and [IF]
  479: 
  480: ' @ alias >code-address ( xt -- c_addr ) \ gforth
  481: \G @i{c-addr} is the code address of the word @i{xt}.
  482: 
  483: : >does-code ( xt -- a_addr ) \ gforth
  484: \G If @i{xt} is the execution token of a child of a @code{DOES>} word,
  485: \G @i{a-addr} is the start of the Forth code after the @code{DOES>};
  486: \G Otherwise @i{a-addr} is 0.
  487:     dup @ dodoes: = if
  488: 	cell+ @
  489:     else
  490: 	drop 0
  491:     endif ;
  492: 
  493: ' ! alias code-address! ( c_addr xt -- ) \ gforth
  494: \G Create a code field with code address @i{c-addr} at @i{xt}.
  495: 
  496: : does-code! ( a_addr xt -- ) \ gforth
  497: \G Create a code field at @i{xt} for a child of a @code{DOES>}-word;
  498: \G @i{a-addr} is the start of the Forth code after @code{DOES>}.
  499:     dodoes: over ! cell+ ! ;
  500: 
  501: ' drop alias does-handler! ( a_addr -- ) \ gforth
  502: \G Create a @code{DOES>}-handler at address @i{a-addr}. Normally,
  503: \G @i{a-addr} points just behind a @code{DOES>}.
  504: 
  505: 2 cells constant /does-handler ( -- n ) \ gforth
  506: \G The size of a @code{DOES>}-handler (includes possible padding).
  507: 
  508: [THEN]	
  509: 
  510: : (search-wordlist)  ( addr count wid -- nt | false )
  511:     dup wordlist-map @ find-method perform ;
  512: 
  513: : search-wordlist ( c-addr count wid -- 0 | xt +-1 ) \ search
  514:     \G Search the word list identified by @i{wid} for the definition
  515:     \G named by the string at @i{c-addr count}.  If the definition is
  516:     \G not found, return 0. If the definition is found return 1 (if
  517:     \G the definition is immediate) or -1 (if the definition is not
  518:     \G immediate) together with the @i{xt}.  In Gforth, the @i{xt}
  519:     \G returned represents the interpretation semantics.  ANS Forth
  520:     \G does not specify clearly what @i{xt} represents.
  521:     (search-wordlist) dup if
  522: 	(name>intn)
  523:     then ;
  524: 
  525: : find-name ( c-addr u -- nt | 0 ) \ gforth
  526:     \g Find the name @i{c-addr u} in the current search
  527:     \g order. Return its @i{nt}, if found, otherwise 0.
  528:     lookup @ (search-wordlist) ;
  529: 
  530: : sfind ( c-addr u -- 0 / xt +-1  ) \ gforth-obsolete
  531:     find-name dup
  532:     if ( nt )
  533: 	state @
  534: 	if
  535: 	    (name>comp)
  536: 	else
  537: 	    (name>intn)
  538: 	then
  539:    then ;
  540: 
  541: : find ( c-addr -- xt +-1 | c-addr 0 ) \ core,search
  542:     \G Search all word lists in the current search order for the
  543:     \G definition named by the counted string at @i{c-addr}.  If the
  544:     \G definition is not found, return 0. If the definition is found
  545:     \G return 1 (if the definition has non-default compilation
  546:     \G semantics) or -1 (if the definition has default compilation
  547:     \G semantics).  The @i{xt} returned in interpret state represents
  548:     \G the interpretation semantics.  The @i{xt} returned in compile
  549:     \G state represented either the compilation semantics (for
  550:     \G non-default compilation semantics) or the run-time semantics
  551:     \G that the compilation semantics would @code{compile,} (for
  552:     \G default compilation semantics).  The ANS Forth standard does
  553:     \G not specify clearly what the returned @i{xt} represents (and
  554:     \G also talks about immediacy instead of non-default compilation
  555:     \G semantics), so this word is questionable in portable programs.
  556:     \G If non-portability is ok, @code{find-name} and friends are
  557:     \G better (@pxref{Name token}).
  558:     dup count sfind dup
  559:     if
  560: 	rot drop
  561:     then ;
  562: 
  563: \ ticks in interpreter
  564: 
  565: : (') ( "name" -- nt ) \ gforth
  566:     name name-too-short?
  567:     find-name dup 0=
  568:     IF
  569: 	drop -&13 throw
  570:     THEN  ;
  571: 
  572: : '    ( "name" -- xt ) \ core	tick
  573:     \g @i{xt} represents @i{name}'s interpretation
  574:     \g semantics. Perform @code{-14 throw} if the word has no
  575:     \g interpretation semantics.
  576:     (') name?int ;
  577: 
  578: has? compiler 0= [IF]	\ interpreter only version of IS and TO
  579: 
  580: : IS ' >body ! ;
  581: ' IS Alias TO
  582: 
  583: [THEN]
  584: 
  585: \ \ the interpreter loop				  mar92py
  586: 
  587: \ interpret                                            10mar92py
  588: 
  589: Defer parser ( c-addr u -- )
  590: Defer parse-word ( "name" -- c-addr u ) \ gforth
  591: \G Get the next word from the input buffer
  592: ' (name) IS parse-word
  593: 
  594: ' parse-word alias name ( -- c-addr u ) \ gforth-obsolete
  595: \G old name for @code{parse-word}
  596: 
  597: Defer compiler-notfound ( c-addr count -- )
  598: Defer interpreter-notfound ( c-addr count -- )
  599: 
  600: : no.extensions  ( addr u -- )
  601:     2drop -&13 throw ;
  602: ' no.extensions IS compiler-notfound
  603: ' no.extensions IS interpreter-notfound
  604: 
  605: Defer before-word ( -- ) \ gforth
  606: \ called before the text interpreter parses the next word
  607: ' noop IS before-word
  608: 
  609: : interpret1 ( ... -- ... )
  610: [ has? backtrace [IF] ]
  611:     rp@ backtrace-rp0 !
  612: [ [THEN] ]
  613:     BEGIN
  614: 	?stack before-word name dup
  615:     WHILE
  616: 	parser
  617:     REPEAT
  618:     2drop ;
  619:     
  620: : interpret ( ?? -- ?? ) \ gforth
  621:     \ interpret/compile the (rest of the) input buffer
  622: [ has? backtrace [IF] ]
  623:     backtrace-rp0 @ >r	
  624: [ [THEN] ]
  625:     ['] interpret1 catch
  626: [ has? backtrace [IF] ]
  627:     r> backtrace-rp0 !
  628:     [ [THEN] ]
  629:     throw ;
  630: 
  631: \ interpreter                                 	30apr92py
  632: 
  633: \ not the most efficient implementations of interpreter and compiler
  634: : interpreter ( c-addr u -- ) 
  635:     2dup find-name dup
  636:     if
  637: 	nip nip name>int execute
  638:     else
  639: 	drop
  640: 	2dup 2>r snumber?
  641: 	IF
  642: 	    2rdrop
  643: 	ELSE
  644: 	    2r> interpreter-notfound
  645: 	THEN
  646:     then ;
  647: 
  648: ' interpreter  IS  parser
  649: 
  650: \ \ Query Evaluate                                 	07apr93py
  651: 
  652: has? file 0= [IF]
  653: : sourceline# ( -- n )  1 ;
  654: [ELSE]
  655: has? new-input 0= [IF]
  656: Variable #fill-bytes
  657: \G number of bytes read via (read-line) by the last refill
  658: [THEN]
  659: [THEN]
  660: 
  661: has? new-input 0= [IF]
  662: : refill ( -- flag ) \ core-ext,block-ext,file-ext
  663:     \G Attempt to fill the input buffer from the input source.  When
  664:     \G the input source is the user input device, attempt to receive
  665:     \G input into the terminal input device. If successful, make the
  666:     \G result the input buffer, set @code{>IN} to 0 and return true;
  667:     \G otherwise return false. When the input source is a block, add 1
  668:     \G to the value of @code{BLK} to make the next block the input
  669:     \G source and current input buffer, and set @code{>IN} to 0;
  670:     \G return true if the new value of @code{BLK} is a valid block
  671:     \G number, false otherwise. When the input source is a text file,
  672:     \G attempt to read the next line from the file. If successful,
  673:     \G make the result the current input buffer, set @code{>IN} to 0
  674:     \G and return true; otherwise, return false.  A successful result
  675:     \G includes receipt of a line containing 0 characters.
  676:     [ has? file [IF] ]
  677: 	blk @  IF  1 blk +!  true  0 >in !  EXIT  THEN
  678: 	[ [THEN] ]
  679:     tib /line
  680:     [ has? file [IF] ]
  681: 	loadfile @ ?dup
  682: 	IF    (read-line) throw #fill-bytes !
  683: 	ELSE
  684: 	    [ [THEN] ]
  685: 	sourceline# 0< IF 2drop false EXIT THEN
  686: 	accept true
  687: 	[ has? file [IF] ]
  688: 	THEN
  689: 	1 loadline +!
  690: 	[ [THEN] ]
  691:     swap #tib ! 0 >in ! ;
  692: 
  693: : query   ( -- ) \ core-ext
  694:     \G Make the user input device the input source. Receive input into
  695:     \G the Terminal Input Buffer. Set @code{>IN} to zero. OBSOLESCENT:
  696:     \G superceeded by @code{accept}.
  697:     [ has? file [IF] ]
  698: 	blk off loadfile off
  699: 	[ [THEN] ]
  700:     refill drop ;
  701: [THEN]
  702: 
  703: \ save-mem extend-mem
  704: 
  705: has? os [IF]
  706: : save-mem	( addr1 u -- addr2 u ) \ gforth
  707:     \g copy a memory block into a newly allocated region in the heap
  708:     swap >r
  709:     dup allocate throw
  710:     swap 2dup r> -rot move ;
  711: 
  712: : free-mem-var ( addr -- )
  713:     \ addr is the address of a 2variable containing address and size
  714:     \ of a memory range; frees memory and clears the 2variable.
  715:     dup 2@ drop dup
  716:     if ( addr mem-start )
  717: 	free throw
  718: 	0 0 rot 2!
  719:     else
  720: 	2drop
  721:     then ;
  722: 
  723: : extend-mem	( addr1 u1 u -- addr addr2 u2 )
  724:     \ extend memory block allocated from the heap by u aus
  725:     \ the (possibly reallocated) piece is addr2 u2, the extension is at addr
  726:     over >r + dup >r resize throw
  727:     r> over r> + -rot ;
  728: [THEN]
  729: 
  730: \ EVALUATE                                              17may93jaw
  731: 
  732: has? file 0= has? new-input 0= and [IF]
  733: : push-file  ( -- )  r>
  734:   tibstack @ >r  >tib @ >r  #tib @ >r
  735:   >tib @ tibstack @ = IF  r@ tibstack +!  THEN
  736:   tibstack @ >tib ! >in @ >r  >r ;
  737: 
  738: : pop-file   ( throw-code -- throw-code )
  739:   r>
  740:   r> >in !  r> #tib !  r> >tib !  r> tibstack !  >r ;
  741: [THEN]
  742: 
  743: has? new-input 0= [IF]
  744: : evaluate ( c-addr u -- ) \ core,block
  745:     \G Save the current input source specification. Store @code{-1} in
  746:     \G @code{source-id} and @code{0} in @code{blk}. Set @code{>IN} to
  747:     \G @code{0} and make the string @i{c-addr u} the input source
  748:     \G and input buffer. Interpret. When the parse area is empty,
  749:     \G restore the input source specification.
  750: [ has? file [IF] ]
  751:     s" *evaluated string*" loadfilename>r
  752: [ [THEN] ]
  753:     push-file #tib ! >tib !
  754:     >in off
  755:     [ has? file [IF] ]
  756: 	blk off loadfile off -1 loadline !
  757: 	[ [THEN] ]
  758:     ['] interpret catch
  759:     pop-file
  760: [ has? file [IF] ]
  761:     r>loadfilename
  762: [ [THEN] ]
  763:     throw ;
  764: [THEN]
  765: 
  766: \ \ Quit                                            	13feb93py
  767: 
  768: Defer 'quit
  769: 
  770: Defer .status
  771: 
  772: : prompt        state @ IF ."  compiled" EXIT THEN ."  ok" ;
  773: 
  774: : (quit) ( -- )
  775:     \ exits only through THROW etc.
  776:     BEGIN
  777: 	.status
  778: 	['] cr catch if
  779: 	    >stderr cr ." Can't print to stdout, leaving" cr
  780: 	    \ if stderr does not work either, already DoError causes a hang
  781: 	    2 (bye)
  782: 	endif
  783: 	query interpret prompt
  784:     AGAIN ;
  785: 
  786: ' (quit) IS 'quit
  787: 
  788: \ \ DOERROR (DOERROR)                        		13jun93jaw
  789: 
  790: 8 Constant max-errors
  791: 4 has? file 2 and + Constant /error
  792: Variable error-stack  0 error-stack !
  793: max-errors /error * cells allot
  794: \ format of one cell:
  795: \ source ( addr u )
  796: \ >in
  797: \ line-number
  798: \ Loadfilename ( addr u )
  799: 
  800: : error> ( -- addr u >in line# [addr u] )
  801:     -1 error-stack +!
  802:     error-stack dup @
  803:     /error * cells + cell+
  804:     /error cells bounds DO
  805: 	I @
  806: 	cell +LOOP ;
  807: : >error ( addr u >in line# [addr u] -- )
  808:     error-stack dup @ dup 1+
  809:     max-errors 1- min error-stack !
  810:     /error * cells + cell+
  811:     /error 1- cells bounds swap DO
  812: 	I !
  813: 	-1 cells +LOOP ;
  814: 
  815: : dec. ( n -- ) \ gforth
  816:     \G Display @i{n} as a signed decimal number, followed by a space.
  817:     \ !! not used...
  818:     base @ decimal swap . base ! ;
  819: 
  820: : dec.r ( u n -- ) \ gforth
  821:     \G Display @i{u} as a unsigned decimal number in a field @i{n}
  822:     \G characters wide.
  823:     base @ >r decimal .r r> base ! ;
  824: 
  825: : hex. ( u -- ) \ gforth
  826:     \G Display @i{u} as an unsigned hex number, prefixed with a "$" and
  827:     \G followed by a space.
  828:     \ !! not used...
  829:     [char] $ emit base @ swap hex u. base ! ;
  830: 
  831: : -trailing  ( c_addr u1 -- c_addr u2 ) \ string dash-trailing
  832: \G Adjust the string specified by @i{c-addr, u1} to remove all
  833: \G trailing spaces. @i{u2} is the length of the modified string.
  834:     BEGIN
  835: 	dup
  836:     WHILE
  837: 	1- 2dup + c@ bl <>
  838:     UNTIL  1+  THEN ;
  839: 
  840: DEFER DOERROR
  841: 
  842: has? backtrace [IF]
  843: Defer dobacktrace ( -- )
  844: ' noop IS dobacktrace
  845: [THEN]
  846: 
  847: : .error-string ( throw-code -- )
  848:   dup -2 = 
  849:   IF 	"error @ ?dup IF count type  THEN drop
  850:   ELSE	.error
  851:   THEN ;
  852: 
  853: : umin ( u1 u2 -- u )
  854:     2dup u>
  855:     if
  856: 	swap
  857:     then
  858:     drop ;
  859: 
  860: Defer mark-start
  861: Defer mark-end
  862: 
  863: :noname ." >>>" ; IS mark-start
  864: :noname ." <<<" ; IS mark-end
  865: 
  866: : .error-line ( addr1 u1 n1 -- )
  867:     \ print error ending at char n1 in line addr1 u1
  868:     \ should work with UTF-8 (whitespace check looks ok)
  869:     over umin \ protect against wrong n1
  870:     swap >r ( addr1 n1 R: u1 )
  871:     -trailing 1- \ last non-space
  872:     0 >r  BEGIN \ search for the first non-space
  873: 	2dup + c@ bl >  WHILE
  874: 	r> 1+ >r  1- dup 0<  UNTIL  THEN  1+
  875:     ( addr1 n2 r: u1 namelen )
  876:     2dup type mark-start
  877:     r> -rot r> swap /string ( namelen addr2 u2 )
  878:     >r swap 2dup type mark-end ( addr2 namelen r: u2 )
  879:     r> swap /string type ;
  880: 
  881: : .error-frame ( throwcode addr1 u1 n1 n2 [addr2 u2] -- throwcode )
  882: \ addr2 u2: 	filename of included file - optional
  883: \ n2:		line number
  884: \ n1:		error position in input line
  885: \ addr1 u1:	input line
  886:   cr error-stack @
  887:   IF ( throwcode addr1 u1 n1 n2 [addr2 u2] )
  888: [ has? file [IF] ] \ !! unbalanced stack effect
  889:     ." in file included from "
  890:     type ." :"
  891: [ [THEN] ] ( throwcode addr1 u1 n1 n2 )
  892:     0 dec.r  drop 2drop
  893:   ELSE ( throwcode addr1 u1 n1 n2 [addr2 u2] )
  894: [ has? file [IF] ]
  895:       type ." :"
  896: [ [THEN] ] ( throwcode addr1 u1 n1 n2 )
  897:       dup 0 dec.r ." : " 4 pick .error-string
  898:       IF \ if line# non-zero, there is a line
  899: 	  cr .error-line
  900:       ELSE
  901: 	  2drop drop
  902:       THEN
  903:   THEN ;
  904: 
  905: : (DoError) ( throw-code -- )
  906:   [ has? os [IF] ]
  907:       >stderr
  908:   [ [THEN] ] 
  909:   source >in @ sourceline# [ has? file [IF] ] \ !! unbalanced stack effect
  910:       sourcefilename
  911:   [ [THEN] ] .error-frame
  912:   error-stack @ 0 ?DO
  913:     error>
  914:     .error-frame
  915:   LOOP
  916:   drop 
  917: [ has? backtrace [IF] ]
  918:   dobacktrace
  919: [ [THEN] ]
  920:   normal-dp dpp ! ;
  921: 
  922: ' (DoError) IS DoError
  923: 
  924: : quit ( ?? -- ?? ) \ core
  925:     \G Empty the return stack, make the user input device
  926:     \G the input source, enter interpret state and start
  927:     \G the text interpreter.
  928:     rp0 @ rp! handler off clear-tibstack
  929:     [ has? new-input 0= [IF] ] >tib @ >r [ [THEN] ]
  930:     BEGIN
  931: 	[ has? compiler [IF] ]
  932: 	    [compile] [
  933: 	[ [THEN] ]
  934: 	\ stack depths may be arbitrary here
  935: 	['] 'quit CATCH dup
  936:     WHILE
  937: 	    <# \ reset hold area, or we may get another error
  938: 	    DoError
  939: 	    \ stack depths may be arbitrary still (or again), so clear them
  940: 	    clearstacks
  941: 	    [ has? new-input [IF] ] clear-tibstack
  942: 	    [ [ELSE] ] r@ >tib ! r@ tibstack !
  943: 	    [ [THEN] ]
  944:     REPEAT
  945:     drop [ has? new-input [IF] ] clear-tibstack
  946:     [ [ELSE] ] r> >tib !
  947:     [ [THEN] ] ;
  948: 
  949: \ \ Cold Boot                                    	13feb93py
  950: 
  951: : (bootmessage)
  952:     ." Gforth " version-string type 
  953:     ." , Copyright (C) 1995-2004 Free Software Foundation, Inc." cr
  954:     ." Gforth comes with ABSOLUTELY NO WARRANTY; for details type `license'"
  955: [ has? os [IF] ]
  956:      cr ." Type `bye' to exit"
  957: [ [THEN] ] ;
  958: 
  959: defer bootmessage
  960: defer process-args
  961: 
  962: ' (bootmessage) IS bootmessage
  963: 
  964: Defer 'cold ( -- ) \ gforth  tick-cold
  965: \ hook (deferred word) for things to do right before interpreting the
  966: \ command-line arguments
  967: ' noop IS 'cold
  968: 
  969: 
  970: AVariable init8 NIL init8 !
  971: 
  972: : cold ( -- ) \ gforth
  973: [ has? backtrace [IF] ]
  974:     rp@ backtrace-rp0 !
  975: [ [THEN] ]
  976: [ has? file [IF] ]
  977:     os-cold
  978: [ [THEN] ]
  979:     set-encoding-fixed-width
  980:     'cold
  981:     init8 chainperform
  982: [ has? file [IF] ]
  983:     s" *the terminal*" loadfilename 2!
  984:     process-args
  985:     loadline off
  986: [ [THEN] ]
  987:     bootmessage
  988:     quit ;
  989: 
  990: has? new-input 0= [IF]
  991: : clear-tibstack ( -- )
  992: [ has? glocals [IF] ]
  993:     lp@ forthstart 7 cells + @ - 
  994: [ [ELSE] ]
  995:     [ has? os [IF] ]
  996:     r0 @ forthstart 6 cells + @ -
  997:     [ [ELSE] ]
  998:     sp@ $10 cells +
  999:     [ [THEN] ]
 1000: [ [THEN] ]
 1001:     dup >tib ! tibstack ! #tib off >in off ;
 1002: [THEN]
 1003: 
 1004: : boot ( path n **argv argc -- )
 1005:     main-task up!
 1006: [ has? os [IF] ]
 1007:     os-boot
 1008: [ [THEN] ]
 1009:     sp@ sp0 !
 1010: [ has? peephole [IF] ]
 1011:     \ only needed for greedy static superinstruction selection
 1012:     \ primtable prepare-peephole-table TO peeptable
 1013: [ [THEN] ]
 1014: [ has? new-input [IF] ]
 1015:     current-input off
 1016: [ [THEN] ]
 1017:     clear-tibstack
 1018:     rp@ rp0 !
 1019: [ has? floating [IF] ]
 1020:     fp@ fp0 !
 1021: [ [THEN] ]
 1022:     handler off
 1023:     ['] cold catch dup -&2049 <> if \ broken pipe?
 1024: 	DoError cr
 1025:     endif
 1026: [ has? os [IF] ]
 1027:     1 (bye) \ !! determin exit code from throw code?
 1028: [ [THEN] ]
 1029: ;
 1030: 
 1031: has? os [IF]
 1032: : bye ( -- ) \ tools-ext
 1033: [ has? file [IF] ]
 1034:     script? 0= IF  cr  THEN
 1035: [ [ELSE] ]
 1036:     cr
 1037: [ [THEN] ]
 1038:     0 (bye) ;
 1039: [THEN]
 1040: 
 1041: \ **argv may be scanned by the C starter to get some important
 1042: \ information, as -display and -geometry for an X client FORTH
 1043: \ or space and stackspace overrides
 1044: 
 1045: \ 0 arg contains, however, the name of the program.
 1046: 

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