File:
[gforth] /
gforth /
blocks.fs
Revision
1.20:
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Sun Dec 13 23:29:58 1998 UTC (24 years, 11 months ago) by
pazsan
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MAIN
CVS tags:
v0-4-0,
HEAD
Added some documentation (files stup, blocks stub, Mini-OOF implementation)
Added Benchres for my machine
made DOS and Win32 compile and run
New gforthmi.bat script for DOS - needs a temporary file for the commands
instead of the -e option.
Added select.o again for DOS (DJGPP's select is broken wrt timing)
Improved select.c
Bug with DOS: engine-ditc doesn't compile with optimization on. Maybe I need
to get a new GCC version for DOS?
1: \ A less simple implementation of the blocks wordset.
2:
3: \ Copyright (C) 1995,1996,1997,1998 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:
22: \ A more efficient implementation would use mmap on OSs that
23: \ provide it and many buffers on OSs that do not provide mmap.
24:
25: \ Now, the replacement algorithm is "direct mapped"; change to LRU
26: \ if too slow. Using more buffers helps, too.
27:
28: \ I think I avoid the assumption 1 char = 1 here, but I have not tested this
29:
30: \ 1024 constant chars/block \ mandated by the standard
31:
32: require struct.fs
33:
34: struct
35: cell% field buffer-block \ the block number
36: cell% field buffer-fid \ the block's fid
37: cell% field buffer-dirty \ the block dirty flag
38: char% chars/block * field block-buffer \ the data
39: cell% 0 * field next-buffer
40: end-struct buffer-struct
41:
42: Variable block-buffers
43: Variable last-block
44:
45: $20 Value buffers
46:
47: User block-fid
48:
49: : block-cold ( -- )
50: block-fid off last-block off
51: buffer-struct buffers * %alloc dup block-buffers ! ( addr )
52: buffer-struct %size buffers * erase ;
53:
54: ' block-cold INIT8 chained
55:
56: block-cold
57:
58: Defer flush-blocks
59:
60: : open-blocks ( addr u -- ) \ gforth
61: \g use the file, whose name is given by @var{addr u}, as blocks file
62: 2dup open-fpath-file 0<>
63: if
64: r/w bin create-file throw
65: else
66: rot close-file throw 2dup file-status throw bin open-file throw
67: >r 2drop r>
68: then
69: block-fid @ IF flush-blocks block-fid @ close-file throw THEN
70: block-fid ! ;
71:
72: : use ( "file" -- ) \ gforth
73: \g use @var{file} as blocks file
74: name open-blocks ;
75:
76: \ the file is opened as binary file, since it either will contain text
77: \ without newlines or binary data
78: : get-block-fid ( -- fid ) \ gforth
79: block-fid @ 0=
80: if
81: s" blocks.fb" open-blocks
82: then
83: block-fid @ ;
84:
85: : block-position ( u -- ) \ block
86: \G positions the block file to the start of block u
87: 1- chars/block chars um* get-block-fid reposition-file throw ;
88:
89: : update ( -- ) \ block
90: last-block @ ?dup IF buffer-dirty on THEN ;
91:
92: : save-buffer ( buffer -- ) \ gforth
93: >r
94: r@ buffer-dirty @ r@ buffer-block @ 0<> and
95: if
96: r@ buffer-block @ block-position
97: r@ block-buffer chars/block r@ buffer-fid @ write-file throw
98: r@ buffer-dirty off
99: endif
100: rdrop ;
101:
102: : empty-buffer ( buffer -- ) \ gforth
103: buffer-block off ;
104:
105: : save-buffers ( -- ) \ block
106: block-buffers @
107: buffers 0 ?DO dup save-buffer next-buffer LOOP drop ;
108:
109: : empty-buffers ( -- ) \ block
110: block-buffers @
111: buffers 0 ?DO dup empty-buffer next-buffer LOOP drop ;
112:
113: : flush ( -- ) \ block
114: save-buffers
115: empty-buffers ;
116:
117: ' flush IS flush-blocks
118:
119: : get-buffer ( n -- a-addr ) \ gforth
120: buffers mod buffer-struct %size * block-buffers @ + ;
121:
122: : block ( u -- a-addr ) \ block
123: dup 0= -35 and throw
124: dup get-buffer >r
125: dup r@ buffer-block @ <>
126: r@ buffer-fid @ block-fid @ <> or
127: if
128: r@ save-buffer
129: dup block-position
130: r@ block-buffer chars/block get-block-fid read-file throw
131: \ clear the rest of the buffer if the file is too short
132: r@ block-buffer over chars + chars/block rot chars - blank
133: r@ buffer-block !
134: get-block-fid r@ buffer-fid !
135: else
136: drop
137: then
138: r> dup last-block ! block-buffer ;
139:
140: : buffer ( u -- a-addr ) \ block
141: \ reading in the block is unnecessary, but simpler
142: block ;
143:
144: User scr 0 scr !
145:
146: : updated? ( n -- f ) \ gforth
147: scr @ buffer
148: [ 0 buffer-dirty 0 block-buffer - ] Literal + @ ;
149:
150: : list ( u -- ) \ block
151: \ calling block again and again looks inefficient but is necessary
152: \ in a multitasking environment
153: dup scr !
154: ." Screen " u.
155: updated? 0= IF ." not " THEN ." modified " cr
156: 16 0
157: ?do
158: i 2 .r space scr @ block i 64 * chars + 64 type cr
159: loop ;
160:
161: : (source) ( -- addr len )
162: blk @ ?dup
163: IF block chars/block
164: ELSE tib #tib @
165: THEN ;
166:
167: ' (source) IS source
168:
169: : load ( i*x n -- j*x ) \ block
170: push-file
171: dup loadline ! blk ! >in off ['] interpret catch
172: pop-file throw ;
173:
174: : thru ( i*x n1 n2 -- j*x ) \ block
175: 1+ swap ?DO I load LOOP ;
176:
177: : +load ( i*x n -- j*x ) \ block
178: blk @ + load ;
179:
180: : +thru ( i*x n1 n2 -- j*x ) \ block
181: 1+ swap ?DO I +load LOOP ;
182:
183: : --> ( -- ) \ block- block
184: refill drop ; immediate
185:
186: : block-included ( addr u -- ) \ gforth
187: block-fid @ >r block-fid off open-blocks
188: 1 load block-fid @ close-file throw flush
189: r> block-fid ! ;
190:
191: \ thrown out because it may provide unpleasant surprises - anton
192: \ : include ( "name" -- )
193: \ name 2dup dup 3 - /string s" .fb" compare
194: \ 0= IF block-included ELSE included THEN ;
195:
196: get-current environment-wordlist set-current
197: true constant block
198: true constant block-ext
199: set-current
200:
201: : bye ['] flush catch drop bye ;
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