| 1 | /* Copyright (C) 1996,1997,2000,2001, 2004, 2006, 2007, 2008, 2009, 2010, |
| 2 | * 2011, 2012, 2013 Free Software Foundation, Inc. |
| 3 | * |
| 4 | * This library is free software; you can redistribute it and/or |
| 5 | * modify it under the terms of the GNU Lesser General Public License |
| 6 | * as published by the Free Software Foundation; either version 3 of |
| 7 | * the License, or (at your option) any later version. |
| 8 | * |
| 9 | * This library is distributed in the hope that it will be useful, but |
| 10 | * WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 12 | * Lesser General Public License for more details. |
| 13 | * |
| 14 | * You should have received a copy of the GNU Lesser General Public |
| 15 | * License along with this library; if not, write to the Free Software |
| 16 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA |
| 17 | * 02110-1301 USA |
| 18 | */ |
| 19 | |
| 20 | #ifdef HAVE_CONFIG_H |
| 21 | # include <config.h> |
| 22 | #endif |
| 23 | |
| 24 | #include <stdio.h> |
| 25 | #include <string.h> |
| 26 | |
| 27 | #include "libguile/_scm.h" |
| 28 | #include "libguile/print.h" |
| 29 | #include "libguile/dynwind.h" |
| 30 | #include "libguile/fluids.h" |
| 31 | #include "libguile/alist.h" |
| 32 | #include "libguile/eval.h" |
| 33 | #include "libguile/ports.h" |
| 34 | #include "libguile/deprecation.h" |
| 35 | #include "libguile/validate.h" |
| 36 | #include "libguile/bdw-gc.h" |
| 37 | |
| 38 | /* Number of additional slots to allocate when ALLOCATED_FLUIDS is full. */ |
| 39 | #define FLUID_GROW 128 |
| 40 | |
| 41 | /* Vector of allocated fluids indexed by fluid numbers. Access is protected by |
| 42 | FLUID_ADMIN_MUTEX. */ |
| 43 | static void **allocated_fluids = NULL; |
| 44 | static size_t allocated_fluids_len = 0; |
| 45 | |
| 46 | static scm_i_pthread_mutex_t fluid_admin_mutex = SCM_I_PTHREAD_MUTEX_INITIALIZER; |
| 47 | |
| 48 | #define IS_FLUID(x) SCM_FLUID_P (x) |
| 49 | #define FLUID_NUM(x) SCM_I_FLUID_NUM (x) |
| 50 | |
| 51 | #define IS_DYNAMIC_STATE(x) SCM_I_DYNAMIC_STATE_P (x) |
| 52 | #define DYNAMIC_STATE_FLUIDS(x) SCM_I_DYNAMIC_STATE_FLUIDS (x) |
| 53 | #define SET_DYNAMIC_STATE_FLUIDS(x, y) SCM_SET_CELL_WORD_1 ((x), (SCM_UNPACK (y))) |
| 54 | |
| 55 | |
| 56 | \f |
| 57 | /* Grow STATE so that it can hold up to ALLOCATED_FLUIDS_LEN fluids. This may |
| 58 | be more than necessary since ALLOCATED_FLUIDS is sparse and the current |
| 59 | thread may not access all the fluids anyway. Memory usage could be improved |
| 60 | by using a 2-level array as is done in glibc for pthread keys (TODO). */ |
| 61 | static void |
| 62 | grow_dynamic_state (SCM state) |
| 63 | { |
| 64 | SCM new_fluids; |
| 65 | SCM old_fluids = DYNAMIC_STATE_FLUIDS (state); |
| 66 | size_t i, len, old_len = SCM_SIMPLE_VECTOR_LENGTH (old_fluids); |
| 67 | |
| 68 | /* Assume the assignment below is atomic. */ |
| 69 | len = allocated_fluids_len; |
| 70 | |
| 71 | new_fluids = scm_c_make_vector (len, SCM_UNDEFINED); |
| 72 | |
| 73 | for (i = 0; i < old_len; i++) |
| 74 | SCM_SIMPLE_VECTOR_SET (new_fluids, i, |
| 75 | SCM_SIMPLE_VECTOR_REF (old_fluids, i)); |
| 76 | SET_DYNAMIC_STATE_FLUIDS (state, new_fluids); |
| 77 | } |
| 78 | |
| 79 | void |
| 80 | scm_i_fluid_print (SCM exp, SCM port, scm_print_state *pstate SCM_UNUSED) |
| 81 | { |
| 82 | scm_puts_unlocked ("#<fluid ", port); |
| 83 | scm_intprint ((int) FLUID_NUM (exp), 10, port); |
| 84 | scm_putc_unlocked ('>', port); |
| 85 | } |
| 86 | |
| 87 | void |
| 88 | scm_i_dynamic_state_print (SCM exp, SCM port, scm_print_state *pstate SCM_UNUSED) |
| 89 | { |
| 90 | scm_puts_unlocked ("#<dynamic-state ", port); |
| 91 | scm_intprint (SCM_UNPACK (exp), 16, port); |
| 92 | scm_putc_unlocked ('>', port); |
| 93 | } |
| 94 | |
| 95 | \f |
| 96 | /* Return a new fluid. */ |
| 97 | static SCM |
| 98 | new_fluid (SCM init) |
| 99 | { |
| 100 | SCM fluid; |
| 101 | size_t trial, n; |
| 102 | |
| 103 | /* Fluids hold the type tag and the fluid number in the first word, |
| 104 | and the default value in the second word. */ |
| 105 | fluid = scm_cell (scm_tc7_fluid, SCM_UNPACK (init)); |
| 106 | SCM_SET_CELL_TYPE (fluid, scm_tc7_fluid); |
| 107 | |
| 108 | scm_dynwind_begin (0); |
| 109 | scm_i_dynwind_pthread_mutex_lock (&fluid_admin_mutex); |
| 110 | |
| 111 | for (trial = 0; trial < 2; trial++) |
| 112 | { |
| 113 | /* Look for a free fluid number. */ |
| 114 | for (n = 0; n < allocated_fluids_len; n++) |
| 115 | /* TODO: Use `__sync_bool_compare_and_swap' where available. */ |
| 116 | if (allocated_fluids[n] == NULL) |
| 117 | break; |
| 118 | |
| 119 | if (trial == 0 && n >= allocated_fluids_len && allocated_fluids_len) |
| 120 | /* All fluid numbers are in use. Run a GC and retry. Explicitly |
| 121 | running the GC is costly and bad-style. We only do this because |
| 122 | dynamic state fluid vectors would grow unreasonably if fluid numbers |
| 123 | weren't reused. */ |
| 124 | scm_i_gc ("fluids"); |
| 125 | } |
| 126 | |
| 127 | if (n >= allocated_fluids_len) |
| 128 | { |
| 129 | /* Grow the vector of allocated fluids. */ |
| 130 | void **new_allocated_fluids = |
| 131 | scm_gc_malloc_pointerless ((allocated_fluids_len + FLUID_GROW) |
| 132 | * sizeof (*allocated_fluids), |
| 133 | "allocated fluids"); |
| 134 | |
| 135 | /* Copy over old values and initialize rest. GC can not run |
| 136 | during these two operations since there is no safe point in |
| 137 | them. */ |
| 138 | memcpy (new_allocated_fluids, allocated_fluids, |
| 139 | allocated_fluids_len * sizeof (*allocated_fluids)); |
| 140 | memset (new_allocated_fluids + allocated_fluids_len, 0, |
| 141 | FLUID_GROW * sizeof (*allocated_fluids)); |
| 142 | n = allocated_fluids_len; |
| 143 | |
| 144 | /* Update the vector of allocated fluids. Dynamic states will |
| 145 | eventually be lazily grown to accomodate the new value of |
| 146 | ALLOCATED_FLUIDS_LEN in `fluid-ref' and `fluid-set!'. */ |
| 147 | allocated_fluids = new_allocated_fluids; |
| 148 | allocated_fluids_len += FLUID_GROW; |
| 149 | } |
| 150 | |
| 151 | allocated_fluids[n] = SCM_UNPACK_POINTER (fluid); |
| 152 | SCM_SET_CELL_WORD_0 (fluid, (scm_tc7_fluid | (n << 8))); |
| 153 | |
| 154 | GC_GENERAL_REGISTER_DISAPPEARING_LINK (&allocated_fluids[n], |
| 155 | SCM2PTR (fluid)); |
| 156 | |
| 157 | scm_dynwind_end (); |
| 158 | |
| 159 | /* Now null out values. We could (and probably should) do this when |
| 160 | the fluid is collected instead of now. */ |
| 161 | scm_i_reset_fluid (n); |
| 162 | |
| 163 | return fluid; |
| 164 | } |
| 165 | |
| 166 | SCM |
| 167 | scm_make_fluid (void) |
| 168 | { |
| 169 | return new_fluid (SCM_BOOL_F); |
| 170 | } |
| 171 | |
| 172 | SCM_DEFINE (scm_make_fluid_with_default, "make-fluid", 0, 1, 0, |
| 173 | (SCM dflt), |
| 174 | "Return a newly created fluid, whose initial value is @var{dflt},\n" |
| 175 | "or @code{#f} if @var{dflt} is not given.\n" |
| 176 | "Fluids are objects that can hold one\n" |
| 177 | "value per dynamic state. That is, modifications to this value are\n" |
| 178 | "only visible to code that executes with the same dynamic state as\n" |
| 179 | "the modifying code. When a new dynamic state is constructed, it\n" |
| 180 | "inherits the values from its parent. Because each thread normally executes\n" |
| 181 | "with its own dynamic state, you can use fluids for thread local storage.") |
| 182 | #define FUNC_NAME s_scm_make_fluid_with_default |
| 183 | { |
| 184 | return new_fluid (SCM_UNBNDP (dflt) ? SCM_BOOL_F : dflt); |
| 185 | } |
| 186 | #undef FUNC_NAME |
| 187 | |
| 188 | SCM_DEFINE (scm_make_unbound_fluid, "make-unbound-fluid", 0, 0, 0, |
| 189 | (), |
| 190 | "Make a fluid that is initially unbound.") |
| 191 | #define FUNC_NAME s_scm_make_unbound_fluid |
| 192 | { |
| 193 | return new_fluid (SCM_UNDEFINED); |
| 194 | } |
| 195 | #undef FUNC_NAME |
| 196 | |
| 197 | SCM_DEFINE (scm_fluid_p, "fluid?", 1, 0, 0, |
| 198 | (SCM obj), |
| 199 | "Return @code{#t} iff @var{obj} is a fluid; otherwise, return\n" |
| 200 | "@code{#f}.") |
| 201 | #define FUNC_NAME s_scm_fluid_p |
| 202 | { |
| 203 | return scm_from_bool (IS_FLUID (obj)); |
| 204 | } |
| 205 | #undef FUNC_NAME |
| 206 | |
| 207 | int |
| 208 | scm_is_fluid (SCM obj) |
| 209 | { |
| 210 | return IS_FLUID (obj); |
| 211 | } |
| 212 | |
| 213 | /* Does not check type of `fluid'! */ |
| 214 | static SCM |
| 215 | fluid_ref (SCM fluid) |
| 216 | { |
| 217 | SCM ret; |
| 218 | SCM fluids = DYNAMIC_STATE_FLUIDS (SCM_I_CURRENT_THREAD->dynamic_state); |
| 219 | |
| 220 | if (SCM_UNLIKELY (FLUID_NUM (fluid) >= SCM_SIMPLE_VECTOR_LENGTH (fluids))) |
| 221 | { |
| 222 | /* Lazily grow the current thread's dynamic state. */ |
| 223 | grow_dynamic_state (SCM_I_CURRENT_THREAD->dynamic_state); |
| 224 | |
| 225 | fluids = DYNAMIC_STATE_FLUIDS (SCM_I_CURRENT_THREAD->dynamic_state); |
| 226 | } |
| 227 | |
| 228 | ret = SCM_SIMPLE_VECTOR_REF (fluids, FLUID_NUM (fluid)); |
| 229 | if (SCM_UNBNDP (ret)) |
| 230 | return SCM_I_FLUID_DEFAULT (fluid); |
| 231 | else |
| 232 | return ret; |
| 233 | } |
| 234 | |
| 235 | SCM_DEFINE (scm_fluid_ref, "fluid-ref", 1, 0, 0, |
| 236 | (SCM fluid), |
| 237 | "Return the value associated with @var{fluid} in the current\n" |
| 238 | "dynamic root. If @var{fluid} has not been set, then return\n" |
| 239 | "@code{#f}.") |
| 240 | #define FUNC_NAME s_scm_fluid_ref |
| 241 | { |
| 242 | SCM val; |
| 243 | SCM_VALIDATE_FLUID (1, fluid); |
| 244 | val = fluid_ref (fluid); |
| 245 | if (SCM_UNBNDP (val)) |
| 246 | SCM_MISC_ERROR ("unbound fluid: ~S", |
| 247 | scm_list_1 (fluid)); |
| 248 | return val; |
| 249 | } |
| 250 | #undef FUNC_NAME |
| 251 | |
| 252 | SCM_DEFINE (scm_fluid_set_x, "fluid-set!", 2, 0, 0, |
| 253 | (SCM fluid, SCM value), |
| 254 | "Set the value associated with @var{fluid} in the current dynamic root.") |
| 255 | #define FUNC_NAME s_scm_fluid_set_x |
| 256 | { |
| 257 | SCM fluids = DYNAMIC_STATE_FLUIDS (SCM_I_CURRENT_THREAD->dynamic_state); |
| 258 | |
| 259 | SCM_VALIDATE_FLUID (1, fluid); |
| 260 | |
| 261 | if (SCM_UNLIKELY (FLUID_NUM (fluid) >= SCM_SIMPLE_VECTOR_LENGTH (fluids))) |
| 262 | { |
| 263 | /* Lazily grow the current thread's dynamic state. */ |
| 264 | grow_dynamic_state (SCM_I_CURRENT_THREAD->dynamic_state); |
| 265 | |
| 266 | fluids = DYNAMIC_STATE_FLUIDS (SCM_I_CURRENT_THREAD->dynamic_state); |
| 267 | } |
| 268 | |
| 269 | SCM_SIMPLE_VECTOR_SET (fluids, FLUID_NUM (fluid), value); |
| 270 | return SCM_UNSPECIFIED; |
| 271 | } |
| 272 | #undef FUNC_NAME |
| 273 | |
| 274 | SCM_DEFINE (scm_fluid_unset_x, "fluid-unset!", 1, 0, 0, |
| 275 | (SCM fluid), |
| 276 | "Unset the value associated with @var{fluid}.") |
| 277 | #define FUNC_NAME s_scm_fluid_unset_x |
| 278 | { |
| 279 | /* FIXME: really unset the default value, too? The current test |
| 280 | suite demands it, but I would prefer not to. */ |
| 281 | SCM_SET_CELL_OBJECT_1 (fluid, SCM_UNDEFINED); |
| 282 | return scm_fluid_set_x (fluid, SCM_UNDEFINED); |
| 283 | } |
| 284 | #undef FUNC_NAME |
| 285 | |
| 286 | SCM_DEFINE (scm_fluid_bound_p, "fluid-bound?", 1, 0, 0, |
| 287 | (SCM fluid), |
| 288 | "Return @code{#t} iff @var{fluid} is bound to a value.\n" |
| 289 | "Throw an error if @var{fluid} is not a fluid.") |
| 290 | #define FUNC_NAME s_scm_fluid_bound_p |
| 291 | { |
| 292 | SCM val; |
| 293 | SCM_VALIDATE_FLUID (1, fluid); |
| 294 | val = fluid_ref (fluid); |
| 295 | return scm_from_bool (! (SCM_UNBNDP (val))); |
| 296 | } |
| 297 | #undef FUNC_NAME |
| 298 | |
| 299 | static SCM |
| 300 | apply_thunk (void *thunk) |
| 301 | { |
| 302 | return scm_call_0 (SCM_PACK (thunk)); |
| 303 | } |
| 304 | |
| 305 | void |
| 306 | scm_swap_fluid (SCM fluid, SCM value_box, SCM dynstate) |
| 307 | { |
| 308 | SCM fluid_vector, tmp; |
| 309 | size_t fluid_num; |
| 310 | |
| 311 | fluid_num = FLUID_NUM (fluid); |
| 312 | |
| 313 | fluid_vector = DYNAMIC_STATE_FLUIDS (dynstate); |
| 314 | |
| 315 | if (SCM_UNLIKELY (fluid_num >= SCM_SIMPLE_VECTOR_LENGTH (fluid_vector))) |
| 316 | { |
| 317 | /* Lazily grow the current thread's dynamic state. */ |
| 318 | grow_dynamic_state (dynstate); |
| 319 | |
| 320 | fluid_vector = DYNAMIC_STATE_FLUIDS (dynstate); |
| 321 | } |
| 322 | |
| 323 | tmp = SCM_SIMPLE_VECTOR_REF (fluid_vector, fluid_num); |
| 324 | SCM_SIMPLE_VECTOR_SET (fluid_vector, fluid_num, SCM_VARIABLE_REF (value_box)); |
| 325 | SCM_VARIABLE_SET (value_box, tmp); |
| 326 | } |
| 327 | |
| 328 | SCM_DEFINE (scm_with_fluids, "with-fluids*", 3, 0, 0, |
| 329 | (SCM fluids, SCM values, SCM thunk), |
| 330 | "Set @var{fluids} to @var{values} temporary, and call @var{thunk}.\n" |
| 331 | "@var{fluids} must be a list of fluids and @var{values} must be the same\n" |
| 332 | "number of their values to be applied. Each substitution is done\n" |
| 333 | "one after another. @var{thunk} must be a procedure with no argument.") |
| 334 | #define FUNC_NAME s_scm_with_fluids |
| 335 | { |
| 336 | return scm_c_with_fluids (fluids, values, |
| 337 | apply_thunk, (void *) SCM_UNPACK (thunk)); |
| 338 | } |
| 339 | #undef FUNC_NAME |
| 340 | |
| 341 | SCM |
| 342 | scm_c_with_fluids (SCM fluids, SCM values, SCM (*cproc) (), void *cdata) |
| 343 | #define FUNC_NAME "scm_c_with_fluids" |
| 344 | { |
| 345 | SCM ans; |
| 346 | long flen, vlen, i; |
| 347 | scm_i_thread *thread = SCM_I_CURRENT_THREAD; |
| 348 | |
| 349 | SCM_VALIDATE_LIST_COPYLEN (1, fluids, flen); |
| 350 | SCM_VALIDATE_LIST_COPYLEN (2, values, vlen); |
| 351 | if (flen != vlen) |
| 352 | scm_out_of_range (s_scm_with_fluids, values); |
| 353 | |
| 354 | for (i = 0; i < flen; i++) |
| 355 | { |
| 356 | scm_dynstack_push_fluid (&thread->dynstack, |
| 357 | SCM_CAR (fluids), SCM_CAR (values), |
| 358 | thread->dynamic_state); |
| 359 | fluids = SCM_CDR (fluids); |
| 360 | values = SCM_CDR (values); |
| 361 | } |
| 362 | |
| 363 | ans = cproc (cdata); |
| 364 | |
| 365 | for (i = 0; i < flen; i++) |
| 366 | scm_dynstack_unwind_fluid (&thread->dynstack, thread->dynamic_state); |
| 367 | |
| 368 | return ans; |
| 369 | } |
| 370 | #undef FUNC_NAME |
| 371 | |
| 372 | SCM |
| 373 | scm_with_fluid (SCM fluid, SCM value, SCM thunk) |
| 374 | { |
| 375 | return scm_c_with_fluid (fluid, value, |
| 376 | apply_thunk, (void *) SCM_UNPACK (thunk)); |
| 377 | } |
| 378 | |
| 379 | SCM |
| 380 | scm_c_with_fluid (SCM fluid, SCM value, SCM (*cproc) (), void *cdata) |
| 381 | #define FUNC_NAME "scm_c_with_fluid" |
| 382 | { |
| 383 | SCM ans; |
| 384 | scm_i_thread *thread = SCM_I_CURRENT_THREAD; |
| 385 | |
| 386 | scm_dynstack_push_fluid (&thread->dynstack, fluid, value, |
| 387 | thread->dynamic_state); |
| 388 | ans = cproc (cdata); |
| 389 | scm_dynstack_unwind_fluid (&thread->dynstack, thread->dynamic_state); |
| 390 | |
| 391 | return ans; |
| 392 | } |
| 393 | #undef FUNC_NAME |
| 394 | |
| 395 | static void |
| 396 | swap_fluid (SCM data) |
| 397 | { |
| 398 | SCM f = SCM_CAR (data); |
| 399 | SCM t = fluid_ref (f); |
| 400 | scm_fluid_set_x (f, SCM_CDR (data)); |
| 401 | SCM_SETCDR (data, t); |
| 402 | } |
| 403 | |
| 404 | void |
| 405 | scm_dynwind_fluid (SCM fluid, SCM value) |
| 406 | { |
| 407 | SCM data = scm_cons (fluid, value); |
| 408 | scm_dynwind_rewind_handler_with_scm (swap_fluid, data, SCM_F_WIND_EXPLICITLY); |
| 409 | scm_dynwind_unwind_handler_with_scm (swap_fluid, data, SCM_F_WIND_EXPLICITLY); |
| 410 | } |
| 411 | |
| 412 | SCM |
| 413 | scm_i_make_initial_dynamic_state () |
| 414 | { |
| 415 | SCM fluids = scm_c_make_vector (allocated_fluids_len, SCM_BOOL_F); |
| 416 | return scm_cell (scm_tc7_dynamic_state, SCM_UNPACK (fluids)); |
| 417 | } |
| 418 | |
| 419 | SCM_DEFINE (scm_make_dynamic_state, "make-dynamic-state", 0, 1, 0, |
| 420 | (SCM parent), |
| 421 | "Return a copy of the dynamic state object @var{parent}\n" |
| 422 | "or of the current dynamic state when @var{parent} is omitted.") |
| 423 | #define FUNC_NAME s_scm_make_dynamic_state |
| 424 | { |
| 425 | SCM fluids; |
| 426 | |
| 427 | if (SCM_UNBNDP (parent)) |
| 428 | parent = scm_current_dynamic_state (); |
| 429 | |
| 430 | SCM_ASSERT (IS_DYNAMIC_STATE (parent), parent, SCM_ARG1, FUNC_NAME); |
| 431 | fluids = scm_vector_copy (DYNAMIC_STATE_FLUIDS (parent)); |
| 432 | return scm_cell (scm_tc7_dynamic_state, SCM_UNPACK (fluids)); |
| 433 | } |
| 434 | #undef FUNC_NAME |
| 435 | |
| 436 | SCM_DEFINE (scm_dynamic_state_p, "dynamic-state?", 1, 0, 0, |
| 437 | (SCM obj), |
| 438 | "Return @code{#t} if @var{obj} is a dynamic state object;\n" |
| 439 | "return @code{#f} otherwise") |
| 440 | #define FUNC_NAME s_scm_dynamic_state_p |
| 441 | { |
| 442 | return scm_from_bool (IS_DYNAMIC_STATE (obj)); |
| 443 | } |
| 444 | #undef FUNC_NAME |
| 445 | |
| 446 | int |
| 447 | scm_is_dynamic_state (SCM obj) |
| 448 | { |
| 449 | return IS_DYNAMIC_STATE (obj); |
| 450 | } |
| 451 | |
| 452 | SCM_DEFINE (scm_current_dynamic_state, "current-dynamic-state", 0, 0, 0, |
| 453 | (), |
| 454 | "Return the current dynamic state object.") |
| 455 | #define FUNC_NAME s_scm_current_dynamic_state |
| 456 | { |
| 457 | return SCM_I_CURRENT_THREAD->dynamic_state; |
| 458 | } |
| 459 | #undef FUNC_NAME |
| 460 | |
| 461 | SCM_DEFINE (scm_set_current_dynamic_state, "set-current-dynamic-state", 1,0,0, |
| 462 | (SCM state), |
| 463 | "Set the current dynamic state object to @var{state}\n" |
| 464 | "and return the previous current dynamic state object.") |
| 465 | #define FUNC_NAME s_scm_set_current_dynamic_state |
| 466 | { |
| 467 | scm_i_thread *t = SCM_I_CURRENT_THREAD; |
| 468 | SCM old = t->dynamic_state; |
| 469 | SCM_ASSERT (IS_DYNAMIC_STATE (state), state, SCM_ARG1, FUNC_NAME); |
| 470 | t->dynamic_state = state; |
| 471 | return old; |
| 472 | } |
| 473 | #undef FUNC_NAME |
| 474 | |
| 475 | static void |
| 476 | swap_dynamic_state (SCM loc) |
| 477 | { |
| 478 | SCM_SETCAR (loc, scm_set_current_dynamic_state (SCM_CAR (loc))); |
| 479 | } |
| 480 | |
| 481 | void |
| 482 | scm_dynwind_current_dynamic_state (SCM state) |
| 483 | { |
| 484 | SCM loc = scm_cons (state, SCM_EOL); |
| 485 | SCM_ASSERT (IS_DYNAMIC_STATE (state), state, SCM_ARG1, NULL); |
| 486 | scm_dynwind_rewind_handler_with_scm (swap_dynamic_state, loc, |
| 487 | SCM_F_WIND_EXPLICITLY); |
| 488 | scm_dynwind_unwind_handler_with_scm (swap_dynamic_state, loc, |
| 489 | SCM_F_WIND_EXPLICITLY); |
| 490 | } |
| 491 | |
| 492 | void * |
| 493 | scm_c_with_dynamic_state (SCM state, void *(*func)(void *), void *data) |
| 494 | { |
| 495 | void *result; |
| 496 | scm_dynwind_begin (SCM_F_DYNWIND_REWINDABLE); |
| 497 | scm_dynwind_current_dynamic_state (state); |
| 498 | result = func (data); |
| 499 | scm_dynwind_end (); |
| 500 | return result; |
| 501 | } |
| 502 | |
| 503 | SCM_DEFINE (scm_with_dynamic_state, "with-dynamic-state", 2, 0, 0, |
| 504 | (SCM state, SCM proc), |
| 505 | "Call @var{proc} while @var{state} is the current dynamic\n" |
| 506 | "state object.") |
| 507 | #define FUNC_NAME s_scm_with_dynamic_state |
| 508 | { |
| 509 | SCM result; |
| 510 | scm_dynwind_begin (SCM_F_DYNWIND_REWINDABLE); |
| 511 | scm_dynwind_current_dynamic_state (state); |
| 512 | result = scm_call_0 (proc); |
| 513 | scm_dynwind_end (); |
| 514 | return result; |
| 515 | } |
| 516 | #undef FUNC_NAME |
| 517 | |
| 518 | |
| 519 | void |
| 520 | scm_init_fluids () |
| 521 | { |
| 522 | #include "libguile/fluids.x" |
| 523 | } |
| 524 | |
| 525 | /* |
| 526 | Local Variables: |
| 527 | c-file-style: "gnu" |
| 528 | End: |
| 529 | */ |