(scm_system): In docstring, refer to status:exit-val rather than
[bpt/guile.git] / libguile / gc.h
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1/* classes: h_files */
2
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3#ifndef SCM_GC_H
4#define SCM_GC_H
8c494e99 5
c35738c1 6/* Copyright (C) 1995,1996,1998,1999,2000,2001, 2002, 2003 Free Software Foundation, Inc.
a00c95d9 7 *
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8 * This library is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
a00c95d9 12 *
73be1d9e 13 * This library is distributed in the hope that it will be useful,
0f2d19dd 14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
a00c95d9 17 *
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18 * You should have received a copy of the GNU Lesser General Public
19 * License along with this library; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21 */
d3a6bc94 22
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23\f
24
b4309c3c 25#include "libguile/__scm.h"
2549a709 26
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27#include "libguile/hooks.h"
28
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29#if SCM_USE_PTHREAD_THREADS
30# include "libguile/pthread-threads.h"
9bc4701c 31#else
ca74704a 32# include "libguile/null-threads.h"
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33#endif
34
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35\f
36
228a24ef 37typedef struct scm_t_cell
2549a709 38{
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39 scm_t_bits word_0;
40 scm_t_bits word_1;
228a24ef 41} scm_t_cell;
2549a709 42
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43/*
44 CARDS
45
46 A card is a small `page' of memory; it will be the unit for lazy
47 sweeping, generations, etc. The first cell of a card contains a
48 pointer to the mark bitvector, so that we can find the bitvector efficiently: we
49 knock off some lowerorder bits.
50
51 The size on a 32 bit machine is 256 cells = 2kb. The card
52*/
2549a709 53
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54
55
56/* Cray machines have pointers that are incremented once for each word,
57 * rather than each byte, the 3 most significant bits encode the byte
58 * within the word. The following macros deal with this by storing the
59 * native Cray pointers like the ones that looks like scm expects. This
228a24ef 60 * is done for any pointers that might appear in the car of a scm_t_cell,
e618c9a3 61 * pointers to scm_vector elts, functions, &c are not munged.
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62 */
63#ifdef _UNICOS
c8a1bdc4 64# define SCM2PTR(x) ((scm_t_cell *) (SCM_UNPACK (x) >> 3))
92c2555f 65# define PTR2SCM(x) (SCM_PACK (((scm_t_bits) (x)) << 3))
2549a709 66#else
c8a1bdc4 67# define SCM2PTR(x) ((scm_t_cell *) (SCM_UNPACK (x)))
92c2555f 68# define PTR2SCM(x) (SCM_PACK ((scm_t_bits) (x)))
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69#endif /* def _UNICOS */
70
c8a1bdc4 71
e618c9a3 72#define SCM_GC_CARD_N_HEADER_CELLS 1
f91f77e6 73#define SCM_GC_CARD_N_CELLS 256
c8a1bdc4 74#define SCM_GC_SIZEOF_CARD SCM_GC_CARD_N_CELLS * sizeof (scm_t_cell)
e618c9a3 75
c8a1bdc4 76#define SCM_GC_CARD_BVEC(card) ((scm_t_c_bvec_long *) ((card)->word_0))
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77#define SCM_GC_SET_CARD_BVEC(card, bvec) \
78 ((card)->word_0 = (scm_t_bits) (bvec))
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79
80
c014a02e 81#define SCM_GC_GET_CARD_FLAGS(card) ((long) ((card)->word_1))
322ec19d 82#define SCM_GC_SET_CARD_FLAGS(card, flags) \
92c2555f 83 ((card)->word_1 = (scm_t_bits) (flags))
c8a1bdc4 84#define SCM_GC_CLEAR_CARD_FLAGS(card) (SCM_GC_SET_CARD_FLAGS (card, 0L))
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85
86#define SCM_GC_GET_CARD_FLAG(card, shift) (SCM_GC_GET_CARD_FLAGS (card) & (1L << (shift)))
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87#define SCM_GC_SET_CARD_FLAG(card, shift) \
88 (SCM_GC_SET_CARD_FLAGS (card, SCM_GC_GET_CARD_FLAGS(card) | (1L << (shift))))
c8a1bdc4 89#define SCM_GC_CLEAR_CARD_FLAG(card, shift) \
322ec19d 90 (SCM_GC_SET_CARD_FLAGS (card, SCM_GC_GET_CARD_FLAGS(card) & ~(1L << (shift))))
e618c9a3 91
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92/*
93 Remove card flags. They hamper lazy initialization, and aren't used
94 anyways.
95 */
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96
97/* card addressing. for efficiency, cards are *always* aligned to
98 SCM_GC_CARD_SIZE. */
99
c8a1bdc4 100#define SCM_GC_CARD_SIZE_MASK (SCM_GC_CARD_N_CELLS * sizeof (scm_t_cell) - 1)
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101#define SCM_GC_CARD_ADDR_MASK (~SCM_GC_CARD_SIZE_MASK)
102
c8a1bdc4 103#define SCM_GC_CELL_CARD(x) ((scm_t_cell *) ((long) (x) & SCM_GC_CARD_ADDR_MASK))
c014a02e 104#define SCM_GC_CELL_OFFSET(x) (((long) (x) & SCM_GC_CARD_SIZE_MASK) >> SCM_CELL_SIZE_SHIFT)
e618c9a3 105#define SCM_GC_CELL_BVEC(x) SCM_GC_CARD_BVEC (SCM_GC_CELL_CARD (x))
c5b0618d 106#define SCM_GC_SET_CELL_BVEC(x, bvec) SCM_GC_SET_CARD_BVEC (SCM_GC_CELL_CARD (x), bvec)
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107#define SCM_GC_CELL_GET_BIT(x) SCM_C_BVEC_GET (SCM_GC_CELL_BVEC (x), SCM_GC_CELL_OFFSET (x))
108#define SCM_GC_CELL_SET_BIT(x) SCM_C_BVEC_SET (SCM_GC_CELL_BVEC (x), SCM_GC_CELL_OFFSET (x))
c8a1bdc4 109#define SCM_GC_CELL_CLEAR_BIT(x) SCM_C_BVEC_CLEAR (SCM_GC_CELL_BVEC (x), SCM_GC_CELL_OFFSET (x))
e618c9a3 110
c8a1bdc4 111#define SCM_GC_CARD_UP(x) SCM_GC_CELL_CARD ((char *) (x) + SCM_GC_SIZEOF_CARD - 1)
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112#define SCM_GC_CARD_DOWN SCM_GC_CELL_CARD
113
114/* low level bit banging aids */
c8a1bdc4 115typedef unsigned long scm_t_c_bvec_long;
e618c9a3 116
48c046bc 117#if (SCM_SIZEOF_UNSIGNED_LONG == 8)
c8a1bdc4 118# define SCM_C_BVEC_LONG_BITS 64
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119# define SCM_C_BVEC_OFFSET_SHIFT 6
120# define SCM_C_BVEC_POS_MASK 63
121# define SCM_CELL_SIZE_SHIFT 4
122#else
c8a1bdc4 123# define SCM_C_BVEC_LONG_BITS 32
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124# define SCM_C_BVEC_OFFSET_SHIFT 5
125# define SCM_C_BVEC_POS_MASK 31
126# define SCM_CELL_SIZE_SHIFT 3
127#endif
128
129#define SCM_C_BVEC_OFFSET(pos) (pos >> SCM_C_BVEC_OFFSET_SHIFT)
130
131#define SCM_C_BVEC_GET(bvec, pos) (bvec[SCM_C_BVEC_OFFSET (pos)] & (1L << (pos & SCM_C_BVEC_POS_MASK)))
132#define SCM_C_BVEC_SET(bvec, pos) (bvec[SCM_C_BVEC_OFFSET (pos)] |= (1L << (pos & SCM_C_BVEC_POS_MASK)))
c8a1bdc4 133#define SCM_C_BVEC_CLEAR(bvec, pos) (bvec[SCM_C_BVEC_OFFSET (pos)] &= ~(1L << (pos & SCM_C_BVEC_POS_MASK)))
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134
135/* testing and changing GC marks */
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136#define SCM_GC_MARK_P(x) SCM_GC_CELL_GET_BIT (x)
137#define SCM_SET_GC_MARK(x) SCM_GC_CELL_SET_BIT (x)
138#define SCM_CLEAR_GC_MARK(x) SCM_GC_CELL_CLEAR_BIT (x)
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139
140/* Low level cell data accessing macros. These macros should only be used
141 * from within code related to garbage collection issues, since they will
142 * never check the cells they are applied to - not even if guile is compiled
143 * in debug mode. In particular these macros will even work for free cells,
144 * which should never be encountered by user code. */
145
146#define SCM_GC_CELL_WORD(x, n) \
147 (((const scm_t_bits *) SCM2PTR (x)) [n])
148#define SCM_GC_CELL_OBJECT(x, n) \
149 (SCM_PACK (((const scm_t_bits *) SCM2PTR (x)) [n]))
150#define SCM_GC_SET_CELL_WORD(x, n, v) \
151 (((scm_t_bits *) SCM2PTR (x)) [n] = (scm_t_bits) (v))
152#define SCM_GC_SET_CELL_OBJECT(x, n, v) \
c8a1bdc4 153 (((scm_t_bits *) SCM2PTR (x)) [n] = SCM_UNPACK (v))
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154#define SCM_GC_CELL_TYPE(x) SCM_GC_CELL_WORD (x, 0)
155
156
157/* Except for the garbage collector, no part of guile should ever run over a
158 * free cell. Thus, if guile is compiled in debug mode the SCM_CELL_* and
159 * SCM_SET_CELL_* macros below report an error if they are applied to a free
160 * cell. Some other plausibility checks are also performed. However, if
161 * guile is not compiled in debug mode, there won't be any time penalty at all
162 * when using these macros. */
2549a709 163
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164#if (SCM_DEBUG_CELL_ACCESSES == 1)
165# define SCM_VALIDATE_CELL(cell, expr) (scm_assert_cell_valid (cell), (expr))
708cb87c 166#else
61045190 167# define SCM_VALIDATE_CELL(cell, expr) (expr)
708cb87c 168#endif
46d53380 169
f706a58b 170#define SCM_CELL_WORD(x, n) \
1fc8902f 171 SCM_VALIDATE_CELL ((x), SCM_GC_CELL_WORD ((x), (n)))
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172#define SCM_CELL_WORD_0(x) SCM_CELL_WORD (x, 0)
173#define SCM_CELL_WORD_1(x) SCM_CELL_WORD (x, 1)
174#define SCM_CELL_WORD_2(x) SCM_CELL_WORD (x, 2)
175#define SCM_CELL_WORD_3(x) SCM_CELL_WORD (x, 3)
176
f706a58b 177#define SCM_CELL_OBJECT(x, n) \
1fc8902f 178 SCM_VALIDATE_CELL ((x), SCM_GC_CELL_OBJECT ((x), (n)))
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179#define SCM_CELL_OBJECT_0(x) SCM_CELL_OBJECT (x, 0)
180#define SCM_CELL_OBJECT_1(x) SCM_CELL_OBJECT (x, 1)
181#define SCM_CELL_OBJECT_2(x) SCM_CELL_OBJECT (x, 2)
182#define SCM_CELL_OBJECT_3(x) SCM_CELL_OBJECT (x, 3)
183
f706a58b 184#define SCM_SET_CELL_WORD(x, n, v) \
1fc8902f 185 SCM_VALIDATE_CELL ((x), SCM_GC_SET_CELL_WORD ((x), (n), (v)))
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186#define SCM_SET_CELL_WORD_0(x, v) SCM_SET_CELL_WORD (x, 0, v)
187#define SCM_SET_CELL_WORD_1(x, v) SCM_SET_CELL_WORD (x, 1, v)
188#define SCM_SET_CELL_WORD_2(x, v) SCM_SET_CELL_WORD (x, 2, v)
189#define SCM_SET_CELL_WORD_3(x, v) SCM_SET_CELL_WORD (x, 3, v)
190
f706a58b 191#define SCM_SET_CELL_OBJECT(x, n, v) \
1fc8902f 192 SCM_VALIDATE_CELL ((x), SCM_GC_SET_CELL_OBJECT ((x), (n), (v)))
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193#define SCM_SET_CELL_OBJECT_0(x, v) SCM_SET_CELL_OBJECT (x, 0, v)
194#define SCM_SET_CELL_OBJECT_1(x, v) SCM_SET_CELL_OBJECT (x, 1, v)
195#define SCM_SET_CELL_OBJECT_2(x, v) SCM_SET_CELL_OBJECT (x, 2, v)
196#define SCM_SET_CELL_OBJECT_3(x, v) SCM_SET_CELL_OBJECT (x, 3, v)
197
198#define SCM_CELL_TYPE(x) SCM_CELL_WORD_0 (x)
199#define SCM_SET_CELL_TYPE(x, t) SCM_SET_CELL_WORD_0 (x, t)
200
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201/* Freelists consist of linked cells where the type entry holds the value
202 * scm_tc_free_cell and the second entry holds a pointer to the next cell of
203 * the freelist. Due to this structure, freelist cells are not cons cells
204 * and thus may not be accessed using SCM_CAR and SCM_CDR. */
61045190 205
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206/*
207 SCM_FREECELL_P removed ; the semantics are ambiguous with lazy
208 sweeping. Could mean "this cell is no longer in use (will be swept)"
209 or "this cell has just been swept, and is not yet in use".
210 */
211
212#define SCM_FREECELL_P this_macro_has_been_removed_see_gc_header_file
213
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214#define SCM_FREE_CELL_CDR(x) \
215 (SCM_GC_CELL_OBJECT ((x), 1))
216#define SCM_SET_FREE_CELL_CDR(x, v) \
217 (SCM_GC_SET_CELL_OBJECT ((x), 1, (v)))
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218
219
92c2555f 220#define SCM_CELL_WORD_LOC(x, n) ((scm_t_bits *) & SCM_CELL_WORD (x, n))
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221#define SCM_CARLOC(x) ((SCM *) SCM_CELL_WORD_LOC ((x), 0))
222#define SCM_CDRLOC(x) ((SCM *) SCM_CELL_WORD_LOC ((x), 1))
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223
224
2549a709 225
79e3f9e2 226
61045190 227#if (SCM_DEBUG_CELL_ACCESSES == 1)
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228/* Set this to != 0 if every cell that is accessed shall be checked:
229 */
230SCM_API int scm_debug_cell_accesses_p;
231SCM_API int scm_expensive_debug_cell_accesses_p;
232SCM_API int scm_debug_cells_gc_interval ;
1e71eafb 233void scm_i_expensive_validation_check (SCM cell);
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234#endif
235
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236SCM_API int scm_block_gc;
237SCM_API int scm_gc_heap_lock;
238SCM_API unsigned int scm_gc_running_p;
2e945bcc 239SCM_API scm_t_rec_mutex scm_i_sweep_mutex;
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240\f
241
c8a1bdc4 242#if (SCM_ENABLE_DEPRECATED == 1)
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243SCM_API size_t scm_default_init_heap_size_1;
244SCM_API int scm_default_min_yield_1;
245SCM_API size_t scm_default_init_heap_size_2;
246SCM_API int scm_default_min_yield_2;
247SCM_API size_t scm_default_max_segment_size;
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248#else
249#define scm_default_init_heap_size_1 deprecated
250#define scm_default_min_yield_1 deprecated
251#define scm_default_init_heap_size_2 deprecated
252#define scm_default_min_yield_2 deprecated
253#define scm_default_max_segment_size deprecated
254#endif
255
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256
257SCM_API size_t scm_max_segment_size;
c8a1bdc4 258
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259#define SCM_FREELIST_CREATE(key) \
260 do { SCM *ls = (SCM *) malloc (sizeof (SCM)); \
261 *ls = SCM_EOL; \
262 scm_setspecific ((key), ls); } while (0)
263#define SCM_FREELIST_LOC(key) ((SCM *) scm_getspecific (key))
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264SCM_API scm_t_key scm_i_freelist;
265SCM_API scm_t_key scm_i_freelist2;
266SCM_API struct scm_t_cell_type_statistics scm_i_master_freelist;
267SCM_API struct scm_t_cell_type_statistics scm_i_master_freelist2;
eab1b259 268
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269
270SCM_API unsigned long scm_gc_cells_swept;
271SCM_API unsigned long scm_gc_cells_collected;
33b001fd 272SCM_API unsigned long scm_gc_cells_collected;
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273SCM_API unsigned long scm_gc_malloc_collected;
274SCM_API unsigned long scm_gc_ports_collected;
f2893a25 275SCM_API unsigned long scm_cells_allocated;
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276SCM_API int scm_gc_cell_yield_percentage;
277SCM_API int scm_gc_malloc_yield_percentage;
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278SCM_API unsigned long scm_mallocated;
279SCM_API unsigned long scm_mtrigger;
280
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281
282
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283SCM_API SCM scm_after_gc_hook;
284
285SCM_API scm_t_c_hook scm_before_gc_c_hook;
286SCM_API scm_t_c_hook scm_before_mark_c_hook;
287SCM_API scm_t_c_hook scm_before_sweep_c_hook;
288SCM_API scm_t_c_hook scm_after_sweep_c_hook;
289SCM_API scm_t_c_hook scm_after_gc_c_hook;
9b3e180c 290
bb2c57fa 291#if defined (GUILE_DEBUG) || defined (GUILE_DEBUG_FREELIST)
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292#if (SCM_ENABLE_DEPRECATED == 1)
293SCM scm_map_free_list (void);
294#else
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295#define scm_map_free_list deprecated
296#define scm_free_list_length deprecated
bb2c57fa 297#endif
2e945bcc 298#endif
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299
300#if (SCM_ENABLE_DEPRECATED == 1) && defined (GUILE_DEBUG_FREELIST)
33b001fd 301SCM_API SCM scm_gc_set_debug_check_freelist_x (SCM flag);
88256b2e 302#endif
0f2d19dd 303\f
0f2d19dd 304
61045190 305#if (SCM_DEBUG_CELL_ACCESSES == 1)
33b001fd 306SCM_API void scm_assert_cell_valid (SCM);
61045190 307#endif
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308
309SCM_API SCM scm_set_debug_cell_accesses_x (SCM flag);
310
311
33b001fd 312SCM_API SCM scm_object_address (SCM obj);
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313SCM_API SCM scm_gc_stats (void);
314SCM_API SCM scm_gc (void);
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315SCM_API void scm_gc_for_alloc (struct scm_t_cell_type_statistics *freelist);
316SCM_API SCM scm_gc_for_newcell (struct scm_t_cell_type_statistics *master, SCM *freelist);
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317SCM_API void scm_igc (const char *what);
318SCM_API void scm_gc_mark (SCM p);
319SCM_API void scm_gc_mark_dependencies (SCM p);
320SCM_API void scm_mark_locations (SCM_STACKITEM x[], unsigned long n);
c8a1bdc4 321SCM_API int scm_in_heap_p (SCM value);
33b001fd 322SCM_API void scm_gc_sweep (void);
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323
324SCM_API void *scm_malloc (size_t size);
ba1b2226 325SCM_API void *scm_calloc (size_t size);
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326SCM_API void *scm_realloc (void *mem, size_t size);
327SCM_API char *scm_strdup (const char *str);
328SCM_API char *scm_strndup (const char *str, size_t n);
329SCM_API void scm_gc_register_collectable_memory (void *mem, size_t size,
330 const char *what);
331SCM_API void scm_gc_unregister_collectable_memory (void *mem, size_t size,
332 const char *what);
39e8f371 333SCM_API void *scm_gc_calloc (size_t size, const char *what);
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334SCM_API void *scm_gc_malloc (size_t size, const char *what);
335SCM_API void *scm_gc_realloc (void *mem, size_t old_size,
336 size_t new_size, const char *what);
337SCM_API void scm_gc_free (void *mem, size_t size, const char *what);
338SCM_API char *scm_gc_strdup (const char *str, const char *what);
339SCM_API char *scm_gc_strndup (const char *str, size_t n, const char *what);
340
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341SCM_API void scm_remember_upto_here_1 (SCM obj);
342SCM_API void scm_remember_upto_here_2 (SCM obj1, SCM obj2);
343SCM_API void scm_remember_upto_here (SCM obj1, ...);
344SCM_API SCM scm_return_first (SCM elt, ...);
345SCM_API int scm_return_first_int (int x, ...);
346SCM_API SCM scm_permanent_object (SCM obj);
347SCM_API SCM scm_gc_protect_object (SCM obj);
348SCM_API SCM scm_gc_unprotect_object (SCM obj);
349SCM_API void scm_gc_register_root (SCM *p);
350SCM_API void scm_gc_unregister_root (SCM *p);
351SCM_API void scm_gc_register_roots (SCM *b, unsigned long n);
352SCM_API void scm_gc_unregister_roots (SCM *b, unsigned long n);
c35738c1 353SCM_API void scm_storage_prehistory (void);
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354SCM_API int scm_init_storage (void);
355SCM_API void *scm_get_stack_base (void);
356SCM_API void scm_init_gc (void);
d1ca2c64 357
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358#if SCM_ENABLE_DEPRECATED == 1
359
360SCM_API SCM scm_deprecated_newcell (void);
361SCM_API SCM scm_deprecated_newcell2 (void);
362
363#define SCM_NEWCELL(_into) \
364 do { _into = scm_deprecated_newcell (); } while (0)
365#define SCM_NEWCELL2(_into) \
366 do { _into = scm_deprecated_newcell2 (); } while (0)
367
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368SCM_API void * scm_must_malloc (size_t len, const char *what);
369SCM_API void * scm_must_realloc (void *where,
370 size_t olen, size_t len,
371 const char *what);
372SCM_API char *scm_must_strdup (const char *str);
373SCM_API char *scm_must_strndup (const char *str, size_t n);
374SCM_API void scm_done_malloc (long size);
375SCM_API void scm_done_free (long size);
376SCM_API void scm_must_free (void *obj);
377
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378#endif
379
61045190 380#endif /* SCM_GC_H */
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381
382/*
383 Local Variables:
384 c-file-style: "gnu"
385 End:
386*/