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16c5cac2 | 1 | /* Copyright (C) 1996,1997,2000,2001, 2004 Free Software Foundation, Inc. |
9482a297 | 2 | * |
73be1d9e MV |
3 | * This library is free software; you can redistribute it and/or |
4 | * modify it under the terms of the GNU Lesser General Public | |
5 | * License as published by the Free Software Foundation; either | |
6 | * version 2.1 of the License, or (at your option) any later version. | |
9482a297 | 7 | * |
73be1d9e MV |
8 | * This library 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 GNU | |
11 | * Lesser General Public License for more details. | |
9482a297 | 12 | * |
73be1d9e MV |
13 | * You should have received a copy of the GNU Lesser General Public |
14 | * License along with this library; if not, write to the Free Software | |
92205699 | 15 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
73be1d9e | 16 | */ |
9482a297 | 17 | |
9de87eea MV |
18 | #include <stdio.h> |
19 | #include <string.h> | |
1bbd0b84 | 20 | |
a0599745 MD |
21 | #include "libguile/_scm.h" |
22 | #include "libguile/print.h" | |
23 | #include "libguile/smob.h" | |
24 | #include "libguile/dynwind.h" | |
25 | #include "libguile/fluids.h" | |
26 | #include "libguile/alist.h" | |
27 | #include "libguile/eval.h" | |
28 | #include "libguile/ports.h" | |
143e0902 | 29 | #include "libguile/deprecation.h" |
c96d76b8 | 30 | #include "libguile/lang.h" |
a0599745 | 31 | #include "libguile/validate.h" |
9482a297 | 32 | |
9de87eea MV |
33 | #define FLUID_GROW 20 |
34 | ||
35 | /* A lot of the complexity below stems from the desire to reuse fluid | |
36 | slots. Normally, fluids should be pretty global and long-lived | |
37 | things, so that reusing their slots should not be overly critical, | |
38 | but it is the right thing to do nevertheless. The code therefore | |
39 | puts the burdon on allocating and collection fluids and keeps | |
40 | accessing fluids lock free. This is achieved by manipulating the | |
41 | global state of the fluid machinery mostly in single threaded | |
42 | sections. | |
43 | ||
44 | Reusing a fluid slot means that it must be reset to #f in all | |
45 | dynamic states. We do this by maintaining a weak list of all | |
46 | dynamic states, which is used after a GC to do the resetting. | |
47 | ||
48 | Also, the fluid vectors in the dynamic states need to grow from | |
49 | time to time when more fluids are created. We do this in a single | |
50 | threaded section so that threads do not need to lock when accessing | |
51 | a fluid in the normal way. | |
52 | */ | |
9482a297 | 53 | |
9de87eea MV |
54 | static scm_i_pthread_mutex_t fluid_admin_mutex = SCM_I_PTHREAD_MUTEX_INITIALIZER; |
55 | ||
56 | /* Protected by fluid_admin_mutex, but also accessed during GC. See | |
57 | next_fluid_num for a discussion of this. | |
58 | */ | |
59 | static size_t allocated_fluids_len = 0; | |
60 | static size_t allocated_fluids_num = 0; | |
61 | static char *allocated_fluids = NULL; | |
62 | ||
63 | static scm_t_bits tc16_fluid; | |
64 | ||
65 | #define IS_FLUID(x) SCM_SMOB_PREDICATE(tc16_fluid, (x)) | |
66 | #define FLUID_NUM(x) ((size_t)SCM_SMOB_DATA(x)) | |
67 | #define FLUID_NEXT(x) SCM_SMOB_OBJECT_2(x) | |
645dd3fc | 68 | #define FLUID_NEXT_LOC(x) SCM_SMOB_OBJECT_2_LOC(x) |
9de87eea MV |
69 | #define SET_FLUID_NEXT(x,y) SCM_SET_SMOB_OBJECT_2((x), (y)) |
70 | ||
71 | static scm_t_bits tc16_dynamic_state; | |
72 | ||
73 | #define IS_DYNAMIC_STATE(x) SCM_SMOB_PREDICATE(tc16_dynamic_state, (x)) | |
74 | #define DYNAMIC_STATE_FLUIDS(x) SCM_SMOB_OBJECT(x) | |
75 | #define SET_DYNAMIC_STATE_FLUIDS(x, y) SCM_SET_SMOB_OBJECT((x), (y)) | |
76 | #define DYNAMIC_STATE_NEXT(x) SCM_SMOB_OBJECT_2(x) | |
645dd3fc | 77 | #define DYNAMIC_STATE_NEXT_LOC(x) SCM_SMOB_OBJECT_2_LOC(x) |
9de87eea MV |
78 | #define SET_DYNAMIC_STATE_NEXT(x, y) SCM_SET_SMOB_OBJECT_2((x), (y)) |
79 | ||
80 | /* Weak lists of all dynamic states and all fluids. | |
81 | */ | |
82 | static SCM all_dynamic_states = SCM_EOL; | |
83 | static SCM all_fluids = SCM_EOL; | |
84 | ||
9de87eea MV |
85 | /* Make sure that all states have the right size. This must be called |
86 | while fluid_admin_mutex is held. | |
87 | */ | |
9482a297 | 88 | static void |
b5fa979c | 89 | resize_all_states () |
9de87eea | 90 | { |
b5fa979c MV |
91 | SCM new_vectors, state; |
92 | ||
93 | /* Replacing the vector of a dynamic state must be done atomically: | |
94 | the old values must be copied into the new vector and the new | |
95 | vector must be installed without someone modifying the old vector | |
96 | concurrently. Since accessing a fluid should be lock-free, we | |
97 | need to put all threads to sleep when replacing a vector. | |
98 | However, when being single threaded, it is best not to do much. | |
99 | Therefore, we allocate the new vectors before going single | |
100 | threaded. | |
101 | */ | |
9de87eea | 102 | |
b5fa979c MV |
103 | new_vectors = SCM_EOL; |
104 | for (state = all_dynamic_states; !scm_is_null (state); | |
105 | state = DYNAMIC_STATE_NEXT (state)) | |
106 | new_vectors = scm_cons (scm_c_make_vector (allocated_fluids_len, | |
107 | SCM_BOOL_F), | |
108 | new_vectors); | |
9de87eea | 109 | |
b5fa979c | 110 | scm_i_thread_put_to_sleep (); |
9de87eea MV |
111 | for (state = all_dynamic_states; !scm_is_null (state); |
112 | state = DYNAMIC_STATE_NEXT (state)) | |
b5fa979c MV |
113 | { |
114 | SCM old_fluids = DYNAMIC_STATE_FLUIDS (state); | |
115 | SCM new_fluids = SCM_CAR (new_vectors); | |
116 | size_t i, old_len = SCM_SIMPLE_VECTOR_LENGTH (old_fluids); | |
9de87eea | 117 | |
b5fa979c MV |
118 | for (i = 0; i < old_len; i++) |
119 | SCM_SIMPLE_VECTOR_SET (new_fluids, i, | |
120 | SCM_SIMPLE_VECTOR_REF (old_fluids, i)); | |
121 | SET_DYNAMIC_STATE_FLUIDS (state, new_fluids); | |
122 | new_vectors = SCM_CDR (new_vectors); | |
123 | } | |
124 | scm_i_thread_wake_up (); | |
9de87eea MV |
125 | } |
126 | ||
127 | /* This is called during GC, that is, while being single threaded. | |
128 | See next_fluid_num for a discussion why it is safe to access | |
129 | allocated_fluids here. | |
130 | */ | |
131 | static void * | |
132 | scan_dynamic_states_and_fluids (void *dummy1 SCM_UNUSED, | |
133 | void *dummy2 SCM_UNUSED, | |
134 | void *dummy3 SCM_UNUSED) | |
9482a297 | 135 | { |
9de87eea | 136 | SCM *statep, *fluidp; |
9482a297 | 137 | |
9de87eea MV |
138 | /* Scan all fluids and deallocate the unmarked ones. |
139 | */ | |
140 | fluidp = &all_fluids; | |
141 | while (!scm_is_null (*fluidp)) | |
9482a297 | 142 | { |
9de87eea MV |
143 | if (!SCM_GC_MARK_P (*fluidp)) |
144 | { | |
145 | allocated_fluids_num -= 1; | |
146 | allocated_fluids[FLUID_NUM (*fluidp)] = 0; | |
147 | *fluidp = FLUID_NEXT (*fluidp); | |
148 | } | |
149 | else | |
645dd3fc | 150 | fluidp = FLUID_NEXT_LOC (*fluidp); |
9482a297 | 151 | } |
9de87eea MV |
152 | |
153 | /* Scan all dynamic states and remove the unmarked ones. The live | |
154 | ones are updated for unallocated fluids. | |
155 | */ | |
156 | statep = &all_dynamic_states; | |
157 | while (!scm_is_null (*statep)) | |
9482a297 | 158 | { |
9de87eea MV |
159 | if (!SCM_GC_MARK_P (*statep)) |
160 | *statep = DYNAMIC_STATE_NEXT (*statep); | |
161 | else | |
162 | { | |
163 | SCM fluids = DYNAMIC_STATE_FLUIDS (*statep); | |
164 | size_t len, i; | |
165 | ||
166 | len = SCM_SIMPLE_VECTOR_LENGTH (fluids); | |
167 | for (i = 0; i < len && i < allocated_fluids_len; i++) | |
168 | if (allocated_fluids[i] == 0) | |
169 | SCM_SIMPLE_VECTOR_SET (fluids, i, SCM_BOOL_F); | |
170 | ||
645dd3fc | 171 | statep = DYNAMIC_STATE_NEXT_LOC (*statep); |
9de87eea | 172 | } |
9482a297 MV |
173 | } |
174 | ||
9de87eea | 175 | return NULL; |
9482a297 MV |
176 | } |
177 | ||
9de87eea MV |
178 | static size_t |
179 | fluid_free (SCM fluid) | |
9482a297 | 180 | { |
9de87eea MV |
181 | /* The real work is done in scan_dynamic_states_and_fluids. We can |
182 | not touch allocated_fluids etc here since a smob free routine can | |
183 | be run at any time, in any thread. | |
184 | */ | |
185 | return 0; | |
9482a297 MV |
186 | } |
187 | ||
9482a297 | 188 | static int |
e81d98ec | 189 | fluid_print (SCM exp, SCM port, scm_print_state *pstate SCM_UNUSED) |
9482a297 | 190 | { |
ed4d7cee | 191 | scm_puts ("#<fluid ", port); |
9de87eea | 192 | scm_intprint ((int) FLUID_NUM (exp), 10, port); |
ed4d7cee GB |
193 | scm_putc ('>', port); |
194 | return 1; | |
9482a297 MV |
195 | } |
196 | ||
9de87eea | 197 | static size_t |
ed4d7cee | 198 | next_fluid_num () |
9482a297 | 199 | { |
9de87eea MV |
200 | size_t n; |
201 | ||
202 | scm_frame_begin (0); | |
203 | scm_i_frame_pthread_mutex_lock (&fluid_admin_mutex); | |
204 | ||
205 | if (allocated_fluids_num == allocated_fluids_len) | |
206 | { | |
207 | /* All fluid numbers are in use. Run a GC to try to free some | |
208 | up. | |
209 | */ | |
210 | scm_gc (); | |
211 | } | |
212 | ||
213 | if (allocated_fluids_num < allocated_fluids_len) | |
214 | { | |
215 | for (n = 0; n < allocated_fluids_len; n++) | |
216 | if (allocated_fluids[n] == 0) | |
217 | break; | |
218 | } | |
219 | else | |
220 | { | |
221 | /* During the following call, the GC might run and elements of | |
222 | allocated_fluids might bet set to zero. Also, | |
223 | allocated_fluids and allocated_fluids_len are used to scan | |
224 | all dynamic states during GC. Thus we need to make sure that | |
225 | no GC can run while updating these two variables. | |
226 | */ | |
227 | ||
228 | char *new_allocated_fluids = | |
229 | scm_malloc (allocated_fluids_len + FLUID_GROW); | |
230 | ||
231 | /* Copy over old values and initialize rest. GC can not run | |
232 | during these two operations since there is no safe point in | |
233 | them. | |
234 | */ | |
235 | memcpy (new_allocated_fluids, allocated_fluids, allocated_fluids_len); | |
236 | memset (new_allocated_fluids + allocated_fluids_len, 0, FLUID_GROW); | |
237 | n = allocated_fluids_len; | |
238 | allocated_fluids = new_allocated_fluids; | |
239 | allocated_fluids_len += FLUID_GROW; | |
240 | ||
241 | /* Now allocated_fluids and allocated_fluids_len are valid again | |
242 | and we can allow GCs to occur. | |
243 | */ | |
b5fa979c | 244 | resize_all_states (); |
9de87eea MV |
245 | } |
246 | ||
247 | allocated_fluids_num += 1; | |
248 | allocated_fluids[n] = 1; | |
249 | ||
250 | scm_frame_end (); | |
9482a297 MV |
251 | return n; |
252 | } | |
253 | ||
a1ec6916 | 254 | SCM_DEFINE (scm_make_fluid, "make-fluid", 0, 0, 0, |
ed4d7cee GB |
255 | (), |
256 | "Return a newly created fluid.\n" | |
9de87eea MV |
257 | "Fluids are objects that can hold one\n" |
258 | "value per dynamic state. That is, modifications to this value are\n" | |
259 | "only visible to code that executes with the same dynamic state as\n" | |
260 | "the modifying code. When a new dynamic state is constructed, it\n" | |
261 | "inherits the values from its parent. Because each thread normally executes\n" | |
262 | "with its own dynamic state, you can use fluids for thread local storage.") | |
1bbd0b84 | 263 | #define FUNC_NAME s_scm_make_fluid |
9482a297 | 264 | { |
9de87eea | 265 | SCM fluid; |
9482a297 | 266 | |
9de87eea MV |
267 | SCM_NEWSMOB2 (fluid, tc16_fluid, |
268 | (scm_t_bits) next_fluid_num (), SCM_UNPACK (SCM_EOL)); | |
269 | ||
270 | /* The GC must not run until the fluid is properly entered into the | |
271 | list. | |
272 | */ | |
b5fa979c | 273 | scm_i_scm_pthread_mutex_lock (&fluid_admin_mutex); |
9de87eea MV |
274 | SET_FLUID_NEXT (fluid, all_fluids); |
275 | all_fluids = fluid; | |
b5fa979c | 276 | scm_i_pthread_mutex_unlock (&fluid_admin_mutex); |
9de87eea MV |
277 | |
278 | return fluid; | |
9482a297 | 279 | } |
1bbd0b84 | 280 | #undef FUNC_NAME |
9482a297 | 281 | |
a1ec6916 | 282 | SCM_DEFINE (scm_fluid_p, "fluid?", 1, 0, 0, |
ed4d7cee | 283 | (SCM obj), |
1e6808ea MG |
284 | "Return @code{#t} iff @var{obj} is a fluid; otherwise, return\n" |
285 | "@code{#f}.") | |
1bbd0b84 | 286 | #define FUNC_NAME s_scm_fluid_p |
b3460a50 | 287 | { |
9de87eea | 288 | return scm_from_bool (IS_FLUID (obj)); |
b3460a50 | 289 | } |
1bbd0b84 | 290 | #undef FUNC_NAME |
b3460a50 | 291 | |
9de87eea MV |
292 | int |
293 | scm_is_fluid (SCM obj) | |
294 | { | |
295 | return IS_FLUID (obj); | |
296 | } | |
297 | ||
298 | size_t | |
299 | scm_i_fluid_num (SCM fluid) | |
300 | { | |
301 | return FLUID_NUM (fluid); | |
302 | } | |
303 | ||
a1ec6916 | 304 | SCM_DEFINE (scm_fluid_ref, "fluid-ref", 1, 0, 0, |
ed4d7cee | 305 | (SCM fluid), |
1e6808ea MG |
306 | "Return the value associated with @var{fluid} in the current\n" |
307 | "dynamic root. If @var{fluid} has not been set, then return\n" | |
308 | "@code{#f}.") | |
1bbd0b84 | 309 | #define FUNC_NAME s_scm_fluid_ref |
9482a297 | 310 | { |
9de87eea | 311 | SCM fluids = DYNAMIC_STATE_FLUIDS (SCM_I_CURRENT_THREAD->dynamic_state); |
9482a297 | 312 | |
ed4d7cee | 313 | SCM_VALIDATE_FLUID (1, fluid); |
9de87eea | 314 | return SCM_SIMPLE_VECTOR_REF (fluids, FLUID_NUM (fluid)); |
9482a297 | 315 | } |
1bbd0b84 | 316 | #undef FUNC_NAME |
9482a297 | 317 | |
9de87eea MV |
318 | SCM |
319 | scm_i_fast_fluid_ref (size_t n) | |
320 | { | |
321 | SCM fluids = DYNAMIC_STATE_FLUIDS (SCM_I_CURRENT_THREAD->dynamic_state); | |
322 | return SCM_SIMPLE_VECTOR_REF (fluids, n); | |
323 | } | |
324 | ||
a1ec6916 | 325 | SCM_DEFINE (scm_fluid_set_x, "fluid-set!", 2, 0, 0, |
ed4d7cee GB |
326 | (SCM fluid, SCM value), |
327 | "Set the value associated with @var{fluid} in the current dynamic root.") | |
1bbd0b84 | 328 | #define FUNC_NAME s_scm_fluid_set_x |
9482a297 | 329 | { |
9de87eea | 330 | SCM fluids = DYNAMIC_STATE_FLUIDS (SCM_I_CURRENT_THREAD->dynamic_state); |
9482a297 | 331 | |
ed4d7cee | 332 | SCM_VALIDATE_FLUID (1, fluid); |
9de87eea | 333 | SCM_SIMPLE_VECTOR_SET (fluids, FLUID_NUM (fluid), value); |
86f9f9ae | 334 | return SCM_UNSPECIFIED; |
9482a297 | 335 | } |
1bbd0b84 | 336 | #undef FUNC_NAME |
9482a297 | 337 | |
9de87eea MV |
338 | void |
339 | scm_i_fast_fluid_set_x (size_t n, SCM value) | |
340 | { | |
341 | SCM fluids = DYNAMIC_STATE_FLUIDS (SCM_I_CURRENT_THREAD->dynamic_state); | |
342 | SCM_SIMPLE_VECTOR_SET (fluids, n, value); | |
343 | } | |
344 | ||
bebd3fba MV |
345 | static void |
346 | swap_fluids (SCM data) | |
b3460a50 | 347 | { |
bebd3fba MV |
348 | SCM fluids = SCM_CAR (data), vals = SCM_CDR (data); |
349 | ||
c96d76b8 | 350 | while (!SCM_NULL_OR_NIL_P (fluids)) |
b3460a50 MV |
351 | { |
352 | SCM fl = SCM_CAR (fluids); | |
353 | SCM old_val = scm_fluid_ref (fl); | |
354 | scm_fluid_set_x (fl, SCM_CAR (vals)); | |
355 | SCM_SETCAR (vals, old_val); | |
356 | fluids = SCM_CDR (fluids); | |
357 | vals = SCM_CDR (vals); | |
358 | } | |
359 | } | |
360 | ||
361 | /* Swap the fluid values in reverse order. This is important when the | |
9de87eea MV |
362 | same fluid appears multiple times in the fluids list. |
363 | */ | |
b3460a50 | 364 | |
bebd3fba MV |
365 | static void |
366 | swap_fluids_reverse_aux (SCM fluids, SCM vals) | |
b3460a50 | 367 | { |
c96d76b8 | 368 | if (!SCM_NULL_OR_NIL_P (fluids)) |
b3460a50 MV |
369 | { |
370 | SCM fl, old_val; | |
371 | ||
bebd3fba | 372 | swap_fluids_reverse_aux (SCM_CDR (fluids), SCM_CDR (vals)); |
b3460a50 MV |
373 | fl = SCM_CAR (fluids); |
374 | old_val = scm_fluid_ref (fl); | |
375 | scm_fluid_set_x (fl, SCM_CAR (vals)); | |
376 | SCM_SETCAR (vals, old_val); | |
377 | } | |
378 | } | |
379 | ||
bebd3fba MV |
380 | static void |
381 | swap_fluids_reverse (SCM data) | |
382 | { | |
383 | swap_fluids_reverse_aux (SCM_CAR (data), SCM_CDR (data)); | |
384 | } | |
1bbd0b84 GB |
385 | |
386 | static SCM | |
387 | apply_thunk (void *thunk) | |
388 | { | |
fdc28395 | 389 | return scm_call_0 (SCM_PACK (thunk)); |
1bbd0b84 GB |
390 | } |
391 | ||
a1ec6916 | 392 | SCM_DEFINE (scm_with_fluids, "with-fluids*", 3, 0, 0, |
ed4d7cee GB |
393 | (SCM fluids, SCM values, SCM thunk), |
394 | "Set @var{fluids} to @var{values} temporary, and call @var{thunk}.\n" | |
395 | "@var{fluids} must be a list of fluids and @var{values} must be the same\n" | |
396 | "number of their values to be applied. Each substitution is done\n" | |
397 | "one after another. @var{thunk} must be a procedure with no argument.") | |
1bbd0b84 GB |
398 | #define FUNC_NAME s_scm_with_fluids |
399 | { | |
bebd3fba MV |
400 | return scm_c_with_fluids (fluids, values, |
401 | apply_thunk, (void *) SCM_UNPACK (thunk)); | |
1bbd0b84 GB |
402 | } |
403 | #undef FUNC_NAME | |
b3460a50 MV |
404 | |
405 | SCM | |
143e0902 MV |
406 | scm_c_with_fluids (SCM fluids, SCM values, SCM (*cproc) (), void *cdata) |
407 | #define FUNC_NAME "scm_c_with_fluids" | |
b3460a50 | 408 | { |
bebd3fba | 409 | SCM ans, data; |
c014a02e | 410 | long flen, vlen; |
b3460a50 | 411 | |
c1bfcf60 | 412 | SCM_VALIDATE_LIST_COPYLEN (1, fluids, flen); |
ed4d7cee | 413 | SCM_VALIDATE_LIST_COPYLEN (2, values, vlen); |
b3460a50 | 414 | if (flen != vlen) |
ed4d7cee | 415 | scm_out_of_range (s_scm_with_fluids, values); |
b3460a50 | 416 | |
bebd3fba MV |
417 | if (flen == 1) |
418 | return scm_c_with_fluid (SCM_CAR (fluids), SCM_CAR (values), | |
419 | cproc, cdata); | |
420 | ||
421 | data = scm_cons (fluids, values); | |
422 | scm_frame_begin (SCM_F_FRAME_REWINDABLE); | |
16c5cac2 MV |
423 | scm_frame_rewind_handler_with_scm (swap_fluids, data, |
424 | SCM_F_WIND_EXPLICITLY); | |
425 | scm_frame_unwind_handler_with_scm (swap_fluids_reverse, data, | |
426 | SCM_F_WIND_EXPLICITLY); | |
b3460a50 | 427 | ans = cproc (cdata); |
bebd3fba | 428 | scm_frame_end (); |
b3460a50 MV |
429 | return ans; |
430 | } | |
c1bfcf60 | 431 | #undef FUNC_NAME |
b3460a50 | 432 | |
bebd3fba MV |
433 | SCM_DEFINE (scm_with_fluid, "with-fluid*", 3, 0, 0, |
434 | (SCM fluid, SCM value, SCM thunk), | |
435 | "Set @var{fluid} to @var{value} temporarily, and call @var{thunk}.\n" | |
436 | "@var{thunk} must be a procedure with no argument.") | |
437 | #define FUNC_NAME s_scm_with_fluid | |
438 | { | |
439 | return scm_c_with_fluid (fluid, value, | |
440 | apply_thunk, (void *) SCM_UNPACK (thunk)); | |
441 | } | |
442 | #undef FUNC_NAME | |
443 | ||
143e0902 MV |
444 | SCM |
445 | scm_c_with_fluid (SCM fluid, SCM value, SCM (*cproc) (), void *cdata) | |
446 | #define FUNC_NAME "scm_c_with_fluid" | |
447 | { | |
bebd3fba MV |
448 | SCM ans; |
449 | ||
450 | scm_frame_begin (SCM_F_FRAME_REWINDABLE); | |
451 | scm_frame_fluid (fluid, value); | |
452 | ans = cproc (cdata); | |
453 | scm_frame_end (); | |
454 | return ans; | |
143e0902 MV |
455 | } |
456 | #undef FUNC_NAME | |
b3460a50 | 457 | |
ef20bf70 MV |
458 | static void |
459 | swap_fluid (SCM data) | |
460 | { | |
461 | SCM f = SCM_CAR (data); | |
462 | SCM t = scm_fluid_ref (f); | |
463 | scm_fluid_set_x (f, SCM_CDR (data)); | |
464 | SCM_SETCDR (data, t); | |
465 | } | |
466 | ||
467 | void | |
468 | scm_frame_fluid (SCM fluid, SCM value) | |
469 | { | |
470 | SCM data = scm_cons (fluid, value); | |
16c5cac2 MV |
471 | scm_frame_rewind_handler_with_scm (swap_fluid, data, SCM_F_WIND_EXPLICITLY); |
472 | scm_frame_unwind_handler_with_scm (swap_fluid, data, SCM_F_WIND_EXPLICITLY); | |
ef20bf70 MV |
473 | } |
474 | ||
9de87eea MV |
475 | SCM |
476 | scm_i_make_initial_dynamic_state () | |
477 | { | |
478 | SCM fluids = scm_c_make_vector (allocated_fluids_len, SCM_BOOL_F); | |
479 | SCM state; | |
480 | SCM_NEWSMOB2 (state, tc16_dynamic_state, | |
481 | SCM_UNPACK (fluids), SCM_UNPACK (SCM_EOL)); | |
482 | all_dynamic_states = state; | |
483 | return state; | |
484 | } | |
485 | ||
486 | SCM_DEFINE (scm_make_dynamic_state, "make-dynamic-state", 0, 1, 0, | |
487 | (SCM parent), | |
488 | "Return a copy of the dynamic state object @var{parent}\n" | |
489 | "or of the current dynamic state when @var{parent} is omitted.") | |
490 | #define FUNC_NAME s_scm_make_dynamic_state | |
491 | { | |
492 | SCM fluids, state; | |
493 | ||
494 | if (SCM_UNBNDP (parent)) | |
495 | parent = scm_current_dynamic_state (); | |
496 | ||
497 | scm_assert_smob_type (tc16_dynamic_state, parent); | |
498 | fluids = scm_vector_copy (DYNAMIC_STATE_FLUIDS (parent)); | |
499 | SCM_NEWSMOB2 (state, tc16_dynamic_state, | |
500 | SCM_UNPACK (fluids), SCM_UNPACK (SCM_EOL)); | |
501 | ||
502 | /* The GC must not run until the state is properly entered into the | |
503 | list. | |
504 | */ | |
b5fa979c | 505 | scm_i_scm_pthread_mutex_lock (&fluid_admin_mutex); |
9de87eea MV |
506 | SET_DYNAMIC_STATE_NEXT (state, all_dynamic_states); |
507 | all_dynamic_states = state; | |
b5fa979c | 508 | scm_i_pthread_mutex_unlock (&fluid_admin_mutex); |
9de87eea | 509 | |
9de87eea MV |
510 | return state; |
511 | } | |
512 | #undef FUNC_NAME | |
513 | ||
514 | SCM_DEFINE (scm_dynamic_state_p, "dynamic-state?", 1, 0, 0, | |
515 | (SCM obj), | |
516 | "Return @code{#t} if @var{obj} is a dynamic state object;\n" | |
517 | "return @code{#f} otherwise") | |
518 | #define FUNC_NAME s_scm_dynamic_state_p | |
519 | { | |
520 | return scm_from_bool (IS_DYNAMIC_STATE (obj)); | |
521 | } | |
522 | #undef FUNC_NAME | |
523 | ||
524 | int | |
525 | scm_is_dynamic_state (SCM obj) | |
526 | { | |
527 | return IS_DYNAMIC_STATE (obj); | |
528 | } | |
529 | ||
530 | SCM_DEFINE (scm_current_dynamic_state, "current-dynamic-state", 0, 0, 0, | |
531 | (), | |
532 | "Return the current dynamic state object.") | |
533 | #define FUNC_NAME s_scm_current_dynamic_state | |
534 | { | |
535 | return SCM_I_CURRENT_THREAD->dynamic_state; | |
536 | } | |
537 | #undef FUNC_NAME | |
538 | ||
539 | SCM_DEFINE (scm_set_current_dynamic_state, "set-current-dynamic-state", 1,0,0, | |
540 | (SCM state), | |
541 | "Set the current dynamic state object to @var{state}\n" | |
542 | "and return the previous current dynamic state object.") | |
543 | #define FUNC_NAME s_scm_set_current_dynamic_state | |
544 | { | |
545 | scm_i_thread *t = SCM_I_CURRENT_THREAD; | |
546 | SCM old = t->dynamic_state; | |
547 | scm_assert_smob_type (tc16_dynamic_state, state); | |
548 | t->dynamic_state = state; | |
549 | return old; | |
550 | } | |
551 | #undef FUNC_NAME | |
552 | ||
553 | static void | |
554 | swap_dynamic_state (SCM loc) | |
555 | { | |
556 | SCM_SETCAR (loc, scm_set_current_dynamic_state (SCM_CAR (loc))); | |
557 | } | |
558 | ||
559 | void | |
560 | scm_frame_current_dynamic_state (SCM state) | |
561 | { | |
562 | SCM loc = scm_cons (state, SCM_EOL); | |
563 | scm_assert_smob_type (tc16_dynamic_state, state); | |
564 | scm_frame_rewind_handler_with_scm (swap_dynamic_state, loc, | |
565 | SCM_F_WIND_EXPLICITLY); | |
566 | scm_frame_unwind_handler_with_scm (swap_dynamic_state, loc, | |
567 | SCM_F_WIND_EXPLICITLY); | |
568 | } | |
569 | ||
570 | void * | |
571 | scm_c_with_dynamic_state (SCM state, void *(*func)(void *), void *data) | |
572 | { | |
573 | void *result; | |
574 | scm_frame_begin (SCM_F_FRAME_REWINDABLE); | |
575 | scm_frame_current_dynamic_state (state); | |
576 | result = func (data); | |
577 | scm_frame_end (); | |
578 | return result; | |
579 | } | |
580 | ||
581 | SCM_DEFINE (scm_with_dynamic_state, "with-dynamic-state", 2, 0, 0, | |
582 | (SCM state, SCM proc), | |
583 | "Call @var{proc} while @var{state} is the current dynamic\n" | |
584 | "state object.") | |
585 | #define FUNC_NAME s_scm_with_dynamic_state | |
586 | { | |
587 | SCM result; | |
588 | scm_frame_begin (SCM_F_FRAME_REWINDABLE); | |
589 | scm_frame_current_dynamic_state (state); | |
590 | result = scm_call_0 (proc); | |
591 | scm_frame_end (); | |
592 | return result; | |
593 | } | |
594 | #undef FUNC_NAME | |
595 | ||
596 | void | |
597 | scm_fluids_prehistory () | |
598 | { | |
599 | tc16_fluid = scm_make_smob_type ("fluid", 0); | |
600 | scm_set_smob_free (tc16_fluid, fluid_free); | |
601 | scm_set_smob_print (tc16_fluid, fluid_print); | |
602 | ||
603 | tc16_dynamic_state = scm_make_smob_type ("dynamic-state", 0); | |
604 | scm_set_smob_mark (tc16_dynamic_state, scm_markcdr); | |
605 | ||
606 | scm_c_hook_add (&scm_after_sweep_c_hook, scan_dynamic_states_and_fluids, | |
607 | 0, 0); | |
608 | } | |
609 | ||
9482a297 MV |
610 | void |
611 | scm_init_fluids () | |
612 | { | |
a0599745 | 613 | #include "libguile/fluids.x" |
9482a297 | 614 | } |
89e00824 ML |
615 | |
616 | /* | |
617 | Local Variables: | |
618 | c-file-style: "gnu" | |
619 | End: | |
620 | */ |