2 * Copyright (c) 1998 Michael Smith <msmith@freebsd.org>
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 #include <sys/cdefs.h>
29 #include <sys/param.h> /* to pick up __FreeBSD_version */
32 #include "bootstrap.h"
35 extern unsigned bootprog_rev
;
37 /* #define BFORTH_DEBUG */
40 # define DEBUG(fmt, args...) printf("%s: " fmt "\n" , __func__ , ## args)
42 # define DEBUG(fmt, args...)
46 * Eventually, all builtin commands throw codes must be defined
47 * elsewhere, possibly bootstrap.h. For now, just this code, used
48 * just in this file, it is getting defined.
53 * FreeBSD loader default dictionary cells
56 #define BF_DICTSIZE 30000
60 * BootForth Interface to Ficl Forth interpreter.
63 ficlSystemInformation
*fsi
;
68 * Shim for taking commands from BF and passing them out to 'standard'
69 * argv/argc command functions.
72 bf_command(ficlVm
*vm
)
74 char *name
, *line
, *tail
, *cp
;
76 struct bootblk_command
**cmdp
;
82 /* Get the name of the current word */
83 name
= vm
->runningWord
->name
;
85 /* Find our command structure */
87 SET_FOREACH(cmdp
, Xcommand_set
) {
88 if (((*cmdp
)->c_name
!= NULL
) && !strcmp(name
, (*cmdp
)->c_name
))
92 panic("callout for unknown command '%s'", name
);
94 /* Check whether we have been compiled or are being interpreted */
95 if (ficlStackPopInteger(ficlVmGetDataStack(vm
))) {
97 * Get parameters from stack, in the format:
98 * an un ... a2 u2 a1 u1 n --
99 * Where n is the number of strings, a/u are pairs of
100 * address/size for strings, and they will be concatenated
103 nstrings
= ficlStackPopInteger(ficlVmGetDataStack(vm
));
104 for (i
= 0, len
= 0; i
< nstrings
; i
++)
105 len
+= ficlStackFetch(ficlVmGetDataStack(vm
), i
* 2).i
+ 1;
106 line
= malloc(strlen(name
) + len
+ 1);
110 for (i
= 0; i
< nstrings
; i
++) {
111 len
= ficlStackPopInteger(ficlVmGetDataStack(vm
));
112 cp
= ficlStackPopPointer(ficlVmGetDataStack(vm
));
114 strncat(line
, cp
, len
);
117 /* Get remainder of invocation */
118 tail
= ficlVmGetInBuf(vm
);
121 for (cp
= tail
; cp
!= vm
->tib
.end
&& *cp
!= 0 && *cp
!= '\n'; cp
++)
124 line
= malloc(strlen(name
) + len
+ 2);
128 strncat(line
, tail
, len
);
129 ficlVmUpdateTib(vm
, tail
+ len
);
132 DEBUG("cmd '%s'", line
);
134 command_errmsg
= command_errbuf
;
135 command_errbuf
[0] = 0;
136 if (!parse(&argc
, &argv
, line
)) {
137 result
= (cmd
)(argc
, argv
);
145 printf("%s\n", command_errmsg
);
146 command_errmsg
= NULL
;
149 panic("%s\n", command_errmsg
);
154 * If there was error during nested ficlExec(), we may no longer have
155 * valid environment to return. Throw all exceptions from here.
157 if (result
!= CMD_OK
)
158 ficlVmThrow(vm
, result
);
160 /* This is going to be thrown!!! */
161 ficlStackPushInteger(ficlVmGetDataStack(vm
),result
);
165 * Replace a word definition (a builtin command) with another
168 * - Throw error results instead of returning them on the stack
169 * - Pass a flag indicating whether the word was compiled or is
172 * There is one major problem with builtins that cannot be overcome
173 * in anyway, except by outlawing it. We want builtins to behave
174 * differently depending on whether they have been compiled or they
175 * are being interpreted. Notice that this is *not* the interpreter's
176 * current state. For example:
178 * : example ls ; immediate
179 * : problem example ; \ "ls" gets executed while compiling
180 * example \ "ls" gets executed while interpreting
182 * Notice that, though the current state is different in the two
183 * invocations of "example", in both cases "ls" has been
184 * *compiled in*, which is what we really want.
186 * The problem arises when you tick the builtin. For example:
188 * : example-1 ['] ls postpone literal ; immediate
189 * : example-2 example-1 execute ; immediate
190 * : problem example-2 ;
193 * We have no way, when we get EXECUTEd, of knowing what our behavior
194 * should be. Thus, our only alternative is to "outlaw" this. See RFI
195 * 0007, and ANS Forth Standard's appendix D, item 6.7 for a related
196 * problem, concerning compile semantics.
198 * The problem is compounded by the fact that "' builtin CATCH" is valid
199 * and desirable. The only solution is to create an intermediary word.
203 * : example ['] my-ls catch ;
205 * So, with the below implementation, here is a summary of the behavior
208 * ls -l \ "interpret" behavior, ie,
209 * \ takes parameters from TIB
210 * : ex-1 s" -l" 1 ls ; \ "compile" behavior, ie,
211 * \ takes parameters from the stack
212 * : ex-2 ['] ls catch ; immediate \ undefined behavior
213 * : ex-3 ['] ls catch ; \ undefined behavior
214 * ex-2 ex-3 \ "interpret" behavior,
216 * : ex-4 ex-2 ; \ "compile" behavior,
217 * \ catch does not work
218 * : ex-5 ex-3 ; immediate \ same as ex-2
219 * : ex-6 ex-3 ; \ same as ex-3
220 * : ex-7 ['] ex-1 catch ; \ "compile" behavior,
222 * : ex-8 postpone ls ; immediate \ same as ex-2
223 * : ex-9 postpone ls ; \ same as ex-3
225 * As the definition below is particularly tricky, and it's side effects
226 * must be well understood by those playing with it, I'll be heavy on
229 * (if you edit this definition, pay attention to trailing spaces after
230 * each word -- I warned you! :-) )
232 #define BUILTIN_CONSTRUCTOR \
234 ">in @ " /* save the tib index pointer */ \
235 "' " /* get next word's xt */ \
236 "swap >in ! " /* point again to next word */ \
237 "create " /* create a new definition of the next word */ \
238 ", " /* save previous definition's xt */ \
239 "immediate " /* make the new definition an immediate word */ \
241 "does> " /* Now, the *new* definition will: */ \
242 "state @ if " /* if in compiling state: */ \
243 "1 postpone literal " /* pass 1 flag to indicate compile */ \
244 "@ compile, " /* compile in previous definition */ \
245 "postpone throw " /* throw stack-returned result */ \
246 "else " /* if in interpreting state: */ \
247 "0 swap " /* pass 0 flag to indicate interpret */ \
248 "@ execute " /* call previous definition */ \
249 "throw " /* throw stack-returned result */ \
253 * Initialise the Forth interpreter, create all our commands as words.
258 struct bootblk_command
**cmdp
;
259 char create_buf
[41]; /* 31 characters-long builtins */
261 ficlDictionary
*dict
;
264 fsi
= malloc(sizeof(ficlSystemInformation
));
265 ficlSystemInformationInitialize(fsi
);
266 fsi
->dictionarySize
= BF_DICTSIZE
;
268 bf_sys
= ficlSystemCreate(fsi
);
269 bf_vm
= ficlSystemCreateVm(bf_sys
);
271 /* Put all private definitions in a "builtins" vocabulary */
272 rv
= ficlVmEvaluate(bf_vm
, "vocabulary builtins also builtins definitions");
273 if (rv
!= FICL_VM_STATUS_OUT_OF_TEXT
) {
274 panic("error interpreting forth: %d\n", rv
);
277 /* Builtin constructor word */
278 rv
= ficlVmEvaluate(bf_vm
, BUILTIN_CONSTRUCTOR
);
279 if (rv
!= FICL_VM_STATUS_OUT_OF_TEXT
) {
280 panic("error interpreting forth: %d\n", rv
);
283 /* make all commands appear as Forth words */
284 dict
= ficlSystemGetDictionary(bf_sys
);
285 SET_FOREACH(cmdp
, Xcommand_set
) {
286 ficlDictionaryAppendPrimitive(dict
, (char *)(*cmdp
)->c_name
,
287 bf_command
, FICL_WORD_DEFAULT
);
288 rv
= ficlVmEvaluate(bf_vm
, "forth definitions builtins");
289 if (rv
!= FICL_VM_STATUS_OUT_OF_TEXT
) {
290 panic("error interpreting forth: %d\n", rv
);
292 sprintf(create_buf
, "builtin: %s", (*cmdp
)->c_name
);
293 rv
= ficlVmEvaluate(bf_vm
, create_buf
);
294 if (rv
!= FICL_VM_STATUS_OUT_OF_TEXT
) {
295 panic("error interpreting forth: %d\n", rv
);
297 rv
= ficlVmEvaluate(bf_vm
, "builtins definitions");
298 if (rv
!= FICL_VM_STATUS_OUT_OF_TEXT
) {
299 panic("error interpreting forth: %d\n", rv
);
302 rv
= ficlVmEvaluate(bf_vm
, "only forth definitions");
303 if (rv
!= FICL_VM_STATUS_OUT_OF_TEXT
) {
304 panic("error interpreting forth: %d\n", rv
);
308 * Export some version numbers so that code can detect the loader/host
311 env
= ficlSystemGetEnvironment(bf_sys
);
312 ficlDictionarySetConstant(env
, "loader_version", bootprog_rev
);
314 /* try to load and run init file if present */
316 rc
= "/boot/forth/boot.4th";
318 fd
= open(rc
, O_RDONLY
);
320 (void)ficlExecFD(bf_vm
, fd
);
327 * Feed a line of user input to the Forth interpreter
335 FICL_STRING_SET_FROM_CSTRING(s
, line
);
336 result
= ficlVmExecuteString(bf_vm
, s
);
338 DEBUG("ficlExec '%s' = %d", line
, result
);
340 case FICL_VM_STATUS_OUT_OF_TEXT
:
341 case FICL_VM_STATUS_ABORTQ
:
342 case FICL_VM_STATUS_QUIT
:
343 case FICL_VM_STATUS_ERROR_EXIT
:
345 case FICL_VM_STATUS_USER_EXIT
:
346 printf("No where to leave to!\n");
348 case FICL_VM_STATUS_ABORT
:
349 printf("Aborted!\n");
352 printf("Parse error!\n");
355 if (command_errmsg
!= NULL
) {
356 printf("%s\n", command_errmsg
);
357 command_errmsg
= NULL
;
361 /* bye is same as reboot and will behave depending on platform */
362 if (result
== FICL_VM_STATUS_USER_EXIT
)
364 setenv("interpret", bf_vm
->state
? "" : "ok", 1);