File:  [gforth] / gforth / struct.fs
Revision 1.15: download - view: text, annotated - select for diffs
Tue Mar 23 20:24:20 1999 UTC (25 years, 1 month ago) by crook
Branches: MAIN
CVS tags: HEAD
Makefile.in

-- changes to make documentation build with moofglos.fs
   rather than with mini-oof.fs (since the former contains glossary
   entries and the latter does not)

assert.fs blocks.fs debug.fs environ.fs errors.fs extend.fs float.fs
glocals.fs moofglos.fs prim search.fs struct.fs stuff.fs vt100.fs
kernel/args.fs kernel/basics.fs kernel/comp.fs kernel/cond.fs
kernel/files.fs kernel/getdoers.fs kernel/int.fs kernel/io.fs
kernel/nio.fs kernel/paths.fs kernel/require.fs kernel/special.fs
kernel/tools.fs kernel/toolsext.fs kernel/vars.fs

-- many small changes to glossary entries.. I think most are done
   now, so I hope to change far fewer files next time!

doc/gforth.ds

-- many, many small changes and a few large ones. Moved some sections
   around, fixed typos and formatting errors, added new section on
   exception handling, rearranged 'files' section.

    1: \ data structures (like C structs)
    2: 
    3: \ Copyright (C) 1995, 1997 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., 675 Mass Ave, Cambridge, MA 02139, USA.
   20: 
   21: : naligned ( addr1 n -- addr2 ) \ gforth
   22: \g @var{addr2} is the aligned version of @var{addr1} with respect to the
   23: \g alignment @var{n}.
   24:  1- tuck +  swap invert and ;
   25: 
   26: ' naligned alias nalign \ old name, obsolete
   27: 
   28: : dozerofield ( -- )
   29:     \ a field that makes no change
   30:     \ to enable accessing the offset with "['] <field> >body @" this
   31:     \ is not implemented with "['] noop alias"
   32:     last @
   33:     if
   34: 	immediate
   35:     then
   36: does> ( name execution: -- )
   37:     drop ;
   38: 
   39: : field, ( align1 offset1 align size --  align2 offset2 )
   40:     swap rot over nalign dup , ( align1 size align offset )
   41:     rot + >r nalign r> ;
   42: 
   43: : create-field ( align1 offset1 align size --  align2 offset2 )
   44:     create field, ;
   45: 
   46: : field ( align1 offset1 align size "name" --  align2 offset2 ) \ gforth
   47:     \G @code{name} execution: @var{addr1} -- @var{addr2}.
   48:     2 pick 
   49:     if \ field offset <> 0
   50: 	[IFDEF]  (Field)
   51: 	    (Field)
   52: 	[ELSE]
   53: 	    Header reveal dofield: cfa,
   54: 	[THEN]
   55:     else
   56: 	create dozerofield
   57:     then
   58:     field, ;
   59: 
   60: : end-struct ( align size "name" -- ) \ gforth
   61: \g @code{name} execution: @var{addr1} -- @var{addr1+offset1}@*
   62: \g Create a field @var{name} with offset @var{offset1}, and the type
   63: \g given by @var{size align}. @var{offset2} is the offset of the
   64: \g next field, and @var{align2} is the alignment of all fields.
   65:     over nalign \ pad size to full alignment
   66:     2constant ;
   67: 
   68: 1 chars 0 end-struct struct ( -- align size ) \ gforth
   69: \g An empty structure, used to start a structure definition.
   70: 
   71: \ type descriptors
   72: 1 aligned   1 cells   2constant cell% ( -- align size ) \ gforth
   73: 1 chars     1 chars   2constant char% ( -- align size ) \ gforth
   74: 1 faligned  1 floats  2constant float% ( -- align size ) \ gforth
   75: 1 dfaligned 1 dfloats 2constant dfloat% ( -- align size ) \ gforth
   76: 1 sfaligned 1 sfloats 2constant sfloat% ( -- align size ) \ gforth
   77: cell% 2*              2constant double% ( -- align size ) \ gforth
   78: 
   79: \ memory allocation words
   80: ' drop alias %alignment ( align size -- align ) \ gforth
   81: \g The alignment of the structure.
   82: ' nip alias %size ( align size -- size ) \ gforth
   83: \g The size of the structure.
   84: 
   85: : %align ( align size -- ) \ gforth
   86:     \G Align the data space pointer to the alignment @var{align}. 
   87:     drop here swap nalign here - allot ;
   88: 
   89: : %allot ( align size -- addr ) \ gforth
   90:     \g Allot @var{size} address units of data space with alignment
   91:     \g @var{align}; the resulting block of data is found at
   92:     \g @var{addr}.
   93:     tuck %align
   94:     here swap allot ;
   95: 
   96: : %allocate ( align size -- addr ior ) \ gforth
   97:     \g Allocate @var{size} address units with alignment @var{align},
   98:     \g similar to @code{allocate}.
   99:     nip allocate ;
  100: 
  101: : %alloc ( size align -- addr ) \ gforth
  102:     \g Allocate @var{size} address units with alignment @var{align},
  103:     \g giving a data block at @var{addr}; @code{throw} an ior code
  104:     \g if not successful.
  105:     %allocate throw ;

FreeBSD-CVSweb <freebsd-cvsweb@FreeBSD.org>