Commit | Line | Data |
---|---|---|
0f2d19dd JB |
1 | /* Copyright (C) 1995,1996 Free Software Foundation, Inc. |
2 | * | |
3 | * This program is free software; you can redistribute it and/or modify | |
4 | * it under the terms of the GNU General Public License as published by | |
5 | * the Free Software Foundation; either version 2, or (at your option) | |
6 | * any later version. | |
7 | * | |
8 | * This program is distributed in the hope that it will be useful, | |
9 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
10 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
11 | * GNU General Public License for more details. | |
12 | * | |
13 | * You should have received a copy of the GNU General Public License | |
14 | * along with this software; see the file COPYING. If not, write to | |
82892bed JB |
15 | * the Free Software Foundation, Inc., 59 Temple Place, Suite 330, |
16 | * Boston, MA 02111-1307 USA | |
0f2d19dd JB |
17 | * |
18 | * As a special exception, the Free Software Foundation gives permission | |
19 | * for additional uses of the text contained in its release of GUILE. | |
20 | * | |
21 | * The exception is that, if you link the GUILE library with other files | |
22 | * to produce an executable, this does not by itself cause the | |
23 | * resulting executable to be covered by the GNU General Public License. | |
24 | * Your use of that executable is in no way restricted on account of | |
25 | * linking the GUILE library code into it. | |
26 | * | |
27 | * This exception does not however invalidate any other reasons why | |
28 | * the executable file might be covered by the GNU General Public License. | |
29 | * | |
30 | * This exception applies only to the code released by the | |
31 | * Free Software Foundation under the name GUILE. If you copy | |
32 | * code from other Free Software Foundation releases into a copy of | |
33 | * GUILE, as the General Public License permits, the exception does | |
34 | * not apply to the code that you add in this way. To avoid misleading | |
35 | * anyone as to the status of such modified files, you must delete | |
36 | * this exception notice from them. | |
37 | * | |
38 | * If you write modifications of your own for GUILE, it is your choice | |
39 | * whether to permit this exception to apply to your modifications. | |
82892bed | 40 | * If you do not wish that, delete this exception notice. */ |
0f2d19dd JB |
41 | \f |
42 | ||
43 | #include <stdio.h> | |
44 | #include "_scm.h" | |
20e6290e | 45 | #include "stackchk.h" |
d564d753 MD |
46 | #include "dynwind.h" |
47 | #include "eval.h" | |
48 | #include "genio.h" | |
49 | #include "smob.h" | |
50 | #include "pairs.h" | |
51 | #include "throw.h" | |
0f2d19dd | 52 | |
20e6290e | 53 | #include "root.h" |
0f2d19dd JB |
54 | \f |
55 | ||
56 | SCM scm_sys_protects[SCM_NUM_PROTECTS]; | |
d564d753 MD |
57 | |
58 | long scm_tc16_root; | |
59 | ||
60 | #ifndef USE_THREADS | |
61 | struct scm_root_state *scm_root; | |
62 | #endif | |
0f2d19dd JB |
63 | |
64 | \f | |
65 | ||
d564d753 MD |
66 | static SCM mark_root SCM_P ((SCM)); |
67 | ||
68 | static SCM | |
69 | mark_root (root) | |
70 | SCM root; | |
71 | { | |
72 | scm_root_state *s = SCM_ROOT_STATE (root); | |
73 | SCM_SETGC8MARK (root); | |
74 | scm_gc_mark (s->rootcont); | |
75 | scm_gc_mark (s->dynwinds); | |
76 | scm_gc_mark (s->continuation_stack); | |
77 | scm_gc_mark (s->continuation_stack_ptr); | |
78 | scm_gc_mark (s->progargs); | |
79 | scm_gc_mark (s->exitval); | |
80 | scm_gc_mark (s->cur_inp); | |
81 | scm_gc_mark (s->cur_outp); | |
82 | scm_gc_mark (s->cur_errp); | |
83 | scm_gc_mark (s->def_inp); | |
84 | scm_gc_mark (s->def_outp); | |
85 | scm_gc_mark (s->def_errp); | |
dc19d1d2 | 86 | scm_gc_mark (s->top_level_lookup_closure_var); |
d564d753 | 87 | scm_gc_mark (s->system_transformer); |
5aab5d96 | 88 | scm_gc_mark (s->the_last_stack_var); |
d564d753 MD |
89 | return SCM_ROOT_STATE (root) -> parent; |
90 | } | |
0f2d19dd | 91 | |
d564d753 MD |
92 | static scm_sizet free_root SCM_P ((SCM)); |
93 | ||
94 | static scm_sizet | |
95 | free_root (root) | |
96 | SCM root; | |
97 | { | |
98 | scm_must_free ((char *) SCM_ROOT_STATE (root)); | |
99 | return sizeof (scm_root_state); | |
100 | } | |
101 | ||
102 | static int print_root SCM_P ((SCM exp, SCM port, scm_print_state *pstate)); | |
103 | ||
104 | static int | |
105 | print_root (exp, port, pstate) | |
106 | SCM exp; | |
107 | SCM port; | |
108 | scm_print_state *pstate; | |
109 | { | |
110 | scm_gen_puts (scm_regular_string, "#<root ", port); | |
111 | scm_intprint(SCM_SEQ (SCM_ROOT_STATE (exp) -> rootcont), 16, port); | |
112 | scm_gen_putc('>', port); | |
113 | return 1; | |
114 | } | |
115 | ||
116 | static scm_smobfuns root_smob = | |
117 | { | |
118 | mark_root, | |
119 | free_root, | |
120 | print_root, | |
121 | 0 | |
122 | }; | |
123 | ||
124 | \f | |
125 | ||
126 | SCM | |
127 | scm_make_root (parent) | |
128 | SCM parent; | |
129 | { | |
130 | SCM root; | |
131 | scm_root_state *root_state; | |
132 | ||
133 | root_state = (scm_root_state *) scm_must_malloc (sizeof (scm_root_state), | |
134 | "scm_make_root"); | |
135 | if (SCM_NIMP (parent) && SCM_ROOTP (parent)) | |
136 | { | |
137 | memcpy (root_state, SCM_ROOT_STATE (parent), sizeof (scm_root_state)); | |
138 | root_state->parent = parent; | |
139 | } | |
140 | else | |
141 | { | |
142 | root_state->parent = SCM_BOOL_F; | |
143 | } | |
144 | SCM_NEWCELL (root); | |
145 | SCM_REDEFER_INTS; | |
146 | SCM_SETCAR (root, scm_tc16_root); | |
147 | SCM_SETCDR (root, root_state); | |
148 | root_state->handle = root; | |
149 | SCM_REALLOW_INTS; | |
150 | return root; | |
151 | } | |
152 | ||
1cc91f1b | 153 | /* {call-with-dynamic-root} |
d564d753 MD |
154 | * |
155 | * Suspending the current thread to evaluate a thunk on the | |
156 | * same C stack but under a new root. | |
157 | * | |
1cc91f1b | 158 | * Calls to call-with-dynamic-root return exactly once (unless |
d564d753 MD |
159 | * the process is somehow exitted). |
160 | */ | |
161 | ||
650fa1ab JB |
162 | /* Some questions about cwdr: |
163 | ||
164 | Couldn't the body just be a closure? Do we really need to pass | |
165 | args through to it? | |
166 | ||
167 | The semantics are a lot like catch's; in fact, we call | |
168 | scm_internal_catch to take care of that part of things. Wouldn't | |
169 | it be cleaner to say that uncaught throws just disappear into the | |
170 | ether (or print a message to stderr), and let the caller use catch | |
171 | themselves if they want to? | |
172 | ||
173 | -JimB */ | |
174 | ||
d564d753 MD |
175 | #if 0 |
176 | SCM scm_exitval; /* INUM with return value */ | |
177 | #endif | |
178 | static int n_dynamic_roots = 0; | |
179 | ||
650fa1ab JB |
180 | |
181 | /* cwdr fills out one of these structures, and then passes a pointer | |
816a6f06 JB |
182 | to it through scm_internal_catch to the cwdr_body function, to tell |
183 | it how to behave. | |
650fa1ab JB |
184 | |
185 | A cwdr is a lot like a catch, except there is no tag (all | |
186 | exceptions are caught), and the body procedure takes the arguments | |
187 | passed to cwdr as A1 and ARGS. */ | |
188 | ||
189 | struct cwdr_body_data { | |
190 | ||
191 | /* Arguments to pass to the cwdr body function. */ | |
192 | SCM a1, args; | |
193 | ||
194 | /* Scheme procedure to use as body of cwdr. */ | |
195 | SCM body_proc; | |
650fa1ab JB |
196 | }; |
197 | ||
198 | ||
199 | /* Invoke the body of a cwdr, assuming that the throw handler has | |
200 | already been set up. DATA points to a struct set up by cwdr that | |
816a6f06 JB |
201 | says what proc to call, and what args to apply it to. |
202 | ||
203 | With a little thought, we could replace this with scm_body_thunk, | |
204 | but I don't want to mess with that at the moment. */ | |
650fa1ab JB |
205 | static SCM cwdr_body SCM_P ((void *, SCM)); |
206 | ||
207 | static SCM | |
208 | cwdr_body (void *data, SCM jmpbuf) | |
209 | { | |
210 | struct cwdr_body_data *c = (struct cwdr_body_data *) data; | |
211 | ||
212 | return scm_apply (c->body_proc, c->a1, c->args); | |
213 | } | |
214 | ||
215 | ||
8938d022 | 216 | static SCM cwdr SCM_P ((SCM thunk, SCM a1, SCM args, SCM handler, SCM_STACKITEM *stack_start)); |
d564d753 MD |
217 | |
218 | /* This is the basic code for new root creation. | |
219 | * | |
220 | * WARNING! The order of actions in this routine is in many ways | |
221 | * critical. E. g., it is essential that an error doesn't leave Guile | |
650fa1ab | 222 | * in a messed up state. */ |
d564d753 MD |
223 | |
224 | static SCM | |
8938d022 MD |
225 | cwdr (proc, a1, args, handler, stack_start) |
226 | SCM proc; | |
d564d753 MD |
227 | SCM a1; |
228 | SCM args; | |
229 | SCM handler; | |
230 | SCM_STACKITEM *stack_start; | |
231 | { | |
232 | int old_ints_disabled = scm_ints_disabled; | |
8938d022 | 233 | SCM old_rootcont, old_winds; |
d564d753 MD |
234 | SCM answer; |
235 | ||
d564d753 MD |
236 | /* Create a fresh root continuation. |
237 | */ | |
238 | { | |
239 | SCM new_rootcont; | |
240 | SCM_NEWCELL (new_rootcont); | |
241 | SCM_REDEFER_INTS; | |
242 | SCM_SETJMPBUF (new_rootcont, | |
0db18cf4 | 243 | scm_must_malloc ((long) sizeof (scm_contregs), |
d564d753 | 244 | "inferior root continuation")); |
a6c64c3c | 245 | SCM_SETCAR (new_rootcont, scm_tc7_contin); |
d564d753 MD |
246 | SCM_DYNENV (new_rootcont) = SCM_EOL; |
247 | SCM_BASE (new_rootcont) = stack_start; | |
8938d022 | 248 | SCM_SEQ (new_rootcont) = ++n_dynamic_roots; |
d564d753 MD |
249 | #ifdef DEBUG_EXTENSIONS |
250 | SCM_DFRAME (new_rootcont) = 0; | |
251 | #endif | |
8938d022 MD |
252 | old_rootcont = scm_rootcont; |
253 | scm_rootcont = new_rootcont; | |
d564d753 MD |
254 | SCM_REALLOW_INTS; |
255 | } | |
256 | ||
8938d022 MD |
257 | /* Exit caller's dynamic state. |
258 | */ | |
259 | old_winds = scm_dynwinds; | |
260 | scm_dowinds (SCM_EOL, scm_ilength (scm_dynwinds)); | |
d564d753 | 261 | #ifdef DEBUG_EXTENSIONS |
308277cb | 262 | SCM_DFRAME (old_rootcont) = scm_last_debug_frame; |
8938d022 | 263 | scm_last_debug_frame = 0; |
d564d753 | 264 | #endif |
d564d753 | 265 | |
d564d753 | 266 | /* Catch all errors. */ |
650fa1ab JB |
267 | { |
268 | struct cwdr_body_data c; | |
269 | ||
270 | c.a1 = a1; | |
271 | c.args = args; | |
272 | c.body_proc = proc; | |
650fa1ab | 273 | |
816a6f06 JB |
274 | answer = scm_internal_catch (SCM_BOOL_T, |
275 | cwdr_body, &c, | |
276 | scm_handle_by_proc, &handler); | |
650fa1ab | 277 | } |
d564d753 MD |
278 | |
279 | scm_dowinds (old_winds, - scm_ilength (old_winds)); | |
280 | SCM_REDEFER_INTS; | |
d564d753 | 281 | #ifdef DEBUG_EXTENSIONS |
308277cb | 282 | scm_last_debug_frame = SCM_DFRAME (old_rootcont); |
d564d753 | 283 | #endif |
308277cb | 284 | scm_rootcont = old_rootcont; |
d564d753 MD |
285 | SCM_REALLOW_INTS; |
286 | scm_ints_disabled = old_ints_disabled; | |
287 | return answer; | |
288 | } | |
289 | ||
290 | ||
8938d022 | 291 | SCM_PROC(s_call_with_dynamic_root, "call-with-dynamic-root", 2, 0, 0, scm_call_with_dynamic_root); |
d564d753 | 292 | SCM |
8938d022 | 293 | scm_call_with_dynamic_root (thunk, handler) |
d564d753 MD |
294 | SCM thunk; |
295 | SCM handler; | |
d564d753 MD |
296 | { |
297 | SCM_STACKITEM stack_place; | |
298 | ||
8938d022 | 299 | return cwdr (thunk, SCM_EOL, SCM_EOL, handler, &stack_place); |
d564d753 MD |
300 | } |
301 | ||
302 | SCM_PROC(s_dynamic_root, "dynamic-root", 0, 0, 0, scm_dynamic_root); | |
d564d753 MD |
303 | SCM |
304 | scm_dynamic_root () | |
d564d753 MD |
305 | { |
306 | return scm_ulong2num (SCM_SEQ (scm_root->rootcont)); | |
307 | } | |
308 | ||
d564d753 | 309 | SCM |
8938d022 | 310 | scm_apply_with_dynamic_root (proc, a1, args, handler) |
d564d753 MD |
311 | SCM proc; |
312 | SCM a1; | |
313 | SCM args; | |
1cc91f1b | 314 | SCM handler; |
d564d753 MD |
315 | { |
316 | SCM_STACKITEM stack_place; | |
8938d022 | 317 | return cwdr (proc, a1, args, handler, &stack_place); |
d564d753 | 318 | } |
0f2d19dd JB |
319 | |
320 | \f | |
321 | ||
322 | /* Call thunk(closure) underneath a top-level error handler. | |
323 | * If an error occurs, pass the exitval through err_filter and return it. | |
324 | * If no error occurs, return the value of thunk. | |
325 | */ | |
326 | ||
327 | ||
328 | #ifdef _UNICOS | |
329 | typedef int setjmp_type; | |
330 | #else | |
331 | typedef long setjmp_type; | |
332 | #endif | |
333 | ||
334 | ||
1cc91f1b | 335 | |
0f2d19dd JB |
336 | SCM |
337 | scm_call_catching_errors (thunk, err_filter, closure) | |
338 | SCM (*thunk)(); | |
339 | SCM (*err_filter)(); | |
d564d753 | 340 | void *closure; |
0f2d19dd JB |
341 | { |
342 | SCM answer; | |
343 | setjmp_type i; | |
faa6b3df | 344 | #ifdef DEBUG_EXTENSIONS |
8938d022 | 345 | SCM_DFRAME (scm_rootcont) = scm_last_debug_frame; |
faa6b3df | 346 | #endif |
0f2d19dd | 347 | i = setjmp (SCM_JMPBUF (scm_rootcont)); |
faa6b3df | 348 | scm_stack_checking_enabled_p = SCM_STACK_CHECKING_P; |
0f2d19dd JB |
349 | if (!i) |
350 | { | |
351 | scm_gc_heap_lock = 0; | |
352 | answer = thunk (closure); | |
353 | } | |
354 | else | |
355 | { | |
356 | scm_gc_heap_lock = 1; | |
357 | answer = err_filter (scm_exitval, closure); | |
358 | } | |
359 | return answer; | |
360 | } | |
361 | ||
d564d753 MD |
362 | void |
363 | scm_init_root () | |
364 | { | |
365 | scm_tc16_root = scm_newsmob (&root_smob); | |
366 | #include "root.x" | |
367 | } |