/usr/include/gc/gc_typed.h is in libgc-dev 1:7.4.2-8ubuntu1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 | /*
* Copyright 1988, 1989 Hans-J. Boehm, Alan J. Demers
* Copyright (c) 1991-1994 by Xerox Corporation. All rights reserved.
* Copyright 1996 Silicon Graphics. All rights reserved.
*
* THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
* OR IMPLIED. ANY USE IS AT YOUR OWN RISK.
*
* Permission is hereby granted to use or copy this program
* for any purpose, provided the above notices are retained on all copies.
* Permission to modify the code and to distribute modified code is granted,
* provided the above notices are retained, and a notice that the code was
* modified is included with the above copyright notice.
*/
/*
* Some simple primitives for allocation with explicit type information.
* Facilities for dynamic type inference may be added later.
* Should be used only for extremely performance critical applications,
* or if conservative collector leakage is otherwise a problem (unlikely).
* Note that this is implemented completely separately from the rest
* of the collector, and is not linked in unless referenced.
* This does not currently support GC_DEBUG in any interesting way.
*/
#ifndef GC_TYPED_H
#define GC_TYPED_H
#ifndef GC_H
# include "gc.h"
#endif
#ifdef __cplusplus
extern "C" {
#endif
typedef GC_word * GC_bitmap;
/* The least significant bit of the first word is one if */
/* the first word in the object may be a pointer. */
#define GC_WORDSZ (8 * sizeof(GC_word))
#define GC_get_bit(bm, index) \
(((bm)[(index) / GC_WORDSZ] >> ((index) % GC_WORDSZ)) & 1)
#define GC_set_bit(bm, index) \
((bm)[(index) / GC_WORDSZ] |= (GC_word)1 << ((index) % GC_WORDSZ))
#define GC_WORD_OFFSET(t, f) (offsetof(t,f) / sizeof(GC_word))
#define GC_WORD_LEN(t) (sizeof(t) / sizeof(GC_word))
#define GC_BITMAP_SIZE(t) ((GC_WORD_LEN(t) + GC_WORDSZ - 1) / GC_WORDSZ)
typedef GC_word GC_descr;
GC_API GC_descr GC_CALL GC_make_descriptor(const GC_word * /* GC_bitmap bm */,
size_t /* len */);
/* Return a type descriptor for the object whose layout */
/* is described by the argument. */
/* The least significant bit of the first word is one */
/* if the first word in the object may be a pointer. */
/* The second argument specifies the number of */
/* meaningful bits in the bitmap. The actual object */
/* may be larger (but not smaller). Any additional */
/* words in the object are assumed not to contain */
/* pointers. */
/* Returns a conservative approximation in the */
/* (unlikely) case of insufficient memory to build */
/* the descriptor. Calls to GC_make_descriptor */
/* may consume some amount of a finite resource. This */
/* is intended to be called once per type, not once */
/* per allocation. */
/* It is possible to generate a descriptor for a C type T with */
/* word aligned pointer fields f1, f2, ... as follows: */
/* */
/* GC_descr T_descr; */
/* GC_word T_bitmap[GC_BITMAP_SIZE(T)] = {0}; */
/* GC_set_bit(T_bitmap, GC_WORD_OFFSET(T,f1)); */
/* GC_set_bit(T_bitmap, GC_WORD_OFFSET(T,f2)); */
/* ... */
/* T_descr = GC_make_descriptor(T_bitmap, GC_WORD_LEN(T)); */
GC_API GC_ATTR_MALLOC GC_ATTR_ALLOC_SIZE(1) void * GC_CALL
GC_malloc_explicitly_typed(size_t /* size_in_bytes */,
GC_descr /* d */);
/* Allocate an object whose layout is described by d. */
/* The resulting object MAY NOT BE PASSED TO REALLOC. */
/* The returned object is cleared. */
GC_API GC_ATTR_MALLOC GC_ATTR_ALLOC_SIZE(1) void * GC_CALL
GC_malloc_explicitly_typed_ignore_off_page(size_t /* size_in_bytes */,
GC_descr /* d */);
GC_API GC_ATTR_MALLOC void * GC_CALL
GC_calloc_explicitly_typed(size_t /* nelements */,
size_t /* element_size_in_bytes */,
GC_descr /* d */);
/* Allocate an array of nelements elements, each of the */
/* given size, and with the given descriptor. */
/* The element size must be a multiple of the byte */
/* alignment required for pointers. E.g. on a 32-bit */
/* machine with 16-bit aligned pointers, size_in_bytes */
/* must be a multiple of 2. */
/* Returned object is cleared. */
#ifdef GC_DEBUG
# define GC_MALLOC_EXPLICITLY_TYPED(bytes, d) GC_MALLOC(bytes)
# define GC_CALLOC_EXPLICITLY_TYPED(n, bytes, d) GC_MALLOC((n) * (bytes))
#else
# define GC_MALLOC_EXPLICITLY_TYPED(bytes, d) \
GC_malloc_explicitly_typed(bytes, d)
# define GC_CALLOC_EXPLICITLY_TYPED(n, bytes, d) \
GC_calloc_explicitly_typed(n, bytes, d)
#endif
#ifdef __cplusplus
} /* matches extern "C" */
#endif
#endif /* GC_TYPED_H */
|