1 \ @(#) c_struct.fth 98/01/26 1.2
2 \ STRUCTUREs are for interfacing with 'C' programs.
3 \ Structures are created using :STRUCT and ;STRUCT
5 \ This file must be loaded before loading any .J files.
8 \ Copyright 1994 3DO, Phil Burk, Larry Polansky, David Rosenboom
10 \ The pForth software code is dedicated to the public domain,
11 \ and any third party may reproduce, distribute and modify
12 \ the pForth software code or any derivative works thereof
13 \ without any compensation or license. The pForth software
14 \ code is provided on an "as is" basis without any warranty
15 \ of any kind, including, without limitation, the implied
16 \ warranties of merchantability and fitness for a particular
17 \ purpose and their equivalents under the laws of any jurisdiction.
19 \ MOD: PLB 1/16/87 Use abort" instead of er.report
20 \ MDH 4/14/87 Added sign-extend words to ..@
21 \ MOD: PLB 9/1/87 Add pointer to last member for debug.
22 \ MOD: MDH 4/30/88 Use fast addressing for ..@ and ..!
23 \ MOD: PLB/MDH 9/30/88 Fixed offsets for 16@+long and 8@+long
24 \ fixed OB.COMPILE.+@/! for 0 offset
25 \ MOD: PLB 1/11/89 Added EVEN-UP in case of last member BYTE
26 \ MOD: RDG 9/19/90 Added floating point member support
27 \ MOD: PLB 12/21/90 Optimized ..@ and ..!
28 \ 00001 PLB 11/20/91 Make structures IMMEDIATE with ALITERAL for speed
29 \ Don't need MOVEQ.L #0,D0 for 16@+WORD and 8@+WORD
30 \ 00002 PLB 8/3/92 Added S@ and S!, and support for RPTR
31 \ 951112 PLB Added FS@ and FS!
32 \ This version for the pForth system.
37 \ STRUCT ======================================================
38 : <:STRUCT> ( pfa -- , run time action for a structure)
40 @ even-up here swap dup ( -- here # # )
41 allot ( make room for ivars )
42 0 fill ( initialize to zero )
44 \ DOES> [compile] aliteral \ 00001
47 \ Contents of a structure definition.
48 \ CELL 0 = size of instantiated structures
49 \ CELL 1 = #bytes to last member name in dictionary.
50 \ this is relative so it will work with structure
51 \ relocation schemes like MODULE
53 : :STRUCT ( -- , Create a 'C' structure )
56 warning" :STRUCT - Previous :STRUCT or :CLASS unfinished!"
57 ob_def_struct ob-state ! ( set pair flags )
59 \ Create new struct defining word.
61 here ob-current-class ! ( set current )
62 0 , ( initial ivar offset )
63 0 , ( location for #byte to last )
67 : ;STRUCT ( -- , terminate structure )
68 ob-state @ ob_def_struct = NOT
69 abort" ;STRUCT - Missing :STRUCT above!"
72 \ Point to last member.
73 latest ob-current-class @ body> >name - ( byte difference of NFAs )
74 ob-current-class @ cell+ !
76 \ Even up byte offset in case last member was BYTE.
77 ob-current-class @ dup @ even-up swap !
80 \ Member reference words.
81 : .. ( object <member> -- member_address , calc addr of member )
82 ob.stats? drop state @
84 IF [compile] literal compile +
91 : (S+C!) ( val addr offset -- ) + c! ;
92 : (S+W!) ( val addr offset -- ) + w! ;
93 : (S+!) ( val addr offset -- ) + ! ;
94 : (S+REL!) ( ptr addr offset -- ) + >r if.use->rel r> ! ;
96 : compile+!bytes ( offset size -- )
97 \ ." compile+!bytes ( " over . dup . ." )" cr
98 swap [compile] literal \ compile offset into word
100 cell OF compile (s+!) ENDOF
101 2 OF compile (s+w!) ENDOF
102 1 OF compile (s+c!) ENDOF
103 -4 OF compile (s+rel!) ENDOF \ 00002
104 -2 OF compile (s+w!) ENDOF
105 -1 OF compile (s+c!) ENDOF
106 true abort" s! - illegal size!"
110 : !BYTES ( value address size -- )
113 -4 OF ( aptr addr ) swap if.use->rel swap ! ENDOF \ 00002
117 true abort" s! - illegal size!"
121 \ These provide ways of setting and reading members values
122 \ without knowing their size in bytes.
123 : (S!) ( offset size -- , compile proper fetch )
126 ELSE ( -- value addr off size )
130 : S! ( value object <member> -- , store value in member )
135 : @BYTES ( addr +/-size -- value )
140 -4 OF @ if.rel->use ENDOF \ 00002
143 true abort" s@ - illegal size!"
147 : (S+UC@) ( addr offset -- val ) + c@ ;
148 : (S+UW@) ( addr offset -- val ) + w@ ;
149 : (S+@) ( addr offset -- val ) + @ ;
150 : (S+REL@) ( addr offset -- val ) + @ if.rel->use ;
151 : (S+C@) ( addr offset -- val ) + c@ b->s ;
152 : (S+W@) ( addr offset -- val ) + w@ w->s ;
154 : compile+@bytes ( offset size -- )
155 \ ." compile+@bytes ( " over . dup . ." )" cr
156 swap [compile] literal \ compile offset into word
158 cell OF compile (s+@) ENDOF
159 2 OF compile (s+uw@) ENDOF
160 1 OF compile (s+uc@) ENDOF
161 -4 OF compile (s+rel@) ENDOF \ 00002
162 -2 OF compile (s+w@) ENDOF
163 -1 OF compile (s+c@) ENDOF
164 true abort" s@ - illegal size!"
168 : (S@) ( offset size -- , compile proper fetch )
175 : S@ ( object <member> -- value , fetch value from member )
183 \ 951112 Floating Point support
184 : FLPT ( <name> -- , declare space for a floating point value. )
187 : (S+F!) ( val addr offset -- ) + f! ;
188 : (S+F@) ( addr offset -- val ) + f@ ;
190 : FS! ( value object <member> -- , fetch value from member )
192 1 floats <> abort" FS@ with non-float!"
200 : FS@ ( object <member> -- value , fetch value from member )
202 1 floats <> abort" FS@ with non-float!"
228 map1 s@ map_s1 -500 - abort" map_s1 failed!"
230 map1 s@ map_s2 -500 $ FFFF and - abort" map_s2 failed!"
232 map1 s@ map_b1 -89 - abort" map_s1 failed!"
234 map1 s@ map_r1 here - abort" map_r1 failed!"
236 map1 s@ map_b2 -89 $ FF and - abort" map_s2 failed!"
237 23.45 map1 fs! map_f1
238 map1 fs@ map_f1 f. ." =?= 23.45" cr
240 ." Testing c_struct.fth" cr