1/* Prototypes and definition for malloc implementation.
2 Copyright (C) 1996-2020 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <https://www.gnu.org/licenses/>. */
18
19#ifndef _MALLOC_H
20#define _MALLOC_H 1
21
22#include <features.h>
23#include <stddef.h>
24#include <stdio.h>
25
26#ifdef _LIBC
27# define __MALLOC_HOOK_VOLATILE
28# define __MALLOC_DEPRECATED
29#else
30# define __MALLOC_HOOK_VOLATILE volatile
31# define __MALLOC_DEPRECATED __attribute_deprecated__
32#endif
33
34
35__BEGIN_DECLS
36
37/* Allocate SIZE bytes of memory. */
38extern void *malloc (size_t __size) __THROW __attribute_malloc__
39 __attribute_alloc_size__ ((1)) __wur;
40
41/* Allocate NMEMB elements of SIZE bytes each, all initialized to 0. */
42extern void *calloc (size_t __nmemb, size_t __size)
43__THROW __attribute_malloc__ __attribute_alloc_size__ ((1, 2)) __wur;
44
45/* Re-allocate the previously allocated block in __ptr, making the new
46 block SIZE bytes long. */
47/* __attribute_malloc__ is not used, because if realloc returns
48 the same pointer that was passed to it, aliasing needs to be allowed
49 between objects pointed by the old and new pointers. */
50extern void *realloc (void *__ptr, size_t __size)
51__THROW __attribute_warn_unused_result__ __attribute_alloc_size__ ((2));
52
53/* Re-allocate the previously allocated block in PTR, making the new
54 block large enough for NMEMB elements of SIZE bytes each. */
55/* __attribute_malloc__ is not used, because if reallocarray returns
56 the same pointer that was passed to it, aliasing needs to be allowed
57 between objects pointed by the old and new pointers. */
58extern void *reallocarray (void *__ptr, size_t __nmemb, size_t __size)
59__THROW __attribute_warn_unused_result__ __attribute_alloc_size__ ((2, 3));
60
61/* Free a block allocated by `malloc', `realloc' or `calloc'. */
62extern void free (void *__ptr) __THROW;
63
64/* Allocate SIZE bytes allocated to ALIGNMENT bytes. */
65extern void *memalign (size_t __alignment, size_t __size)
66__THROW __attribute_malloc__ __attribute_alloc_size__ ((2)) __wur;
67
68/* Allocate SIZE bytes on a page boundary. */
69extern void *valloc (size_t __size) __THROW __attribute_malloc__
70 __attribute_alloc_size__ ((1)) __wur;
71
72/* Equivalent to valloc(minimum-page-that-holds(n)), that is, round up
73 __size to nearest pagesize. */
74extern void *pvalloc (size_t __size) __THROW __attribute_malloc__ __wur;
75
76/* Underlying allocation function; successive calls should return
77 contiguous pieces of memory. */
78extern void *(*__morecore) (ptrdiff_t __size) __MALLOC_DEPRECATED;
79
80/* Default value of `__morecore'. */
81extern void *__default_morecore (ptrdiff_t __size)
82__THROW __attribute_malloc__ __MALLOC_DEPRECATED;
83
84/* SVID2/XPG mallinfo structure */
85
86struct mallinfo
87{
88 int arena; /* non-mmapped space allocated from system */
89 int ordblks; /* number of free chunks */
90 int smblks; /* number of fastbin blocks */
91 int hblks; /* number of mmapped regions */
92 int hblkhd; /* space in mmapped regions */
93 int usmblks; /* always 0, preserved for backwards compatibility */
94 int fsmblks; /* space available in freed fastbin blocks */
95 int uordblks; /* total allocated space */
96 int fordblks; /* total free space */
97 int keepcost; /* top-most, releasable (via malloc_trim) space */
98};
99
100/* Returns a copy of the updated current mallinfo. */
101extern struct mallinfo mallinfo (void) __THROW;
102
103/* SVID2/XPG mallopt options */
104#ifndef M_MXFAST
105# define M_MXFAST 1 /* maximum request size for "fastbins" */
106#endif
107#ifndef M_NLBLKS
108# define M_NLBLKS 2 /* UNUSED in this malloc */
109#endif
110#ifndef M_GRAIN
111# define M_GRAIN 3 /* UNUSED in this malloc */
112#endif
113#ifndef M_KEEP
114# define M_KEEP 4 /* UNUSED in this malloc */
115#endif
116
117/* mallopt options that actually do something */
118#define M_TRIM_THRESHOLD -1
119#define M_TOP_PAD -2
120#define M_MMAP_THRESHOLD -3
121#define M_MMAP_MAX -4
122#define M_CHECK_ACTION -5
123#define M_PERTURB -6
124#define M_ARENA_TEST -7
125#define M_ARENA_MAX -8
126
127/* General SVID/XPG interface to tunable parameters. */
128extern int mallopt (int __param, int __val) __THROW;
129
130/* Release all but __pad bytes of freed top-most memory back to the
131 system. Return 1 if successful, else 0. */
132extern int malloc_trim (size_t __pad) __THROW;
133
134/* Report the number of usable allocated bytes associated with allocated
135 chunk __ptr. */
136extern size_t malloc_usable_size (void *__ptr) __THROW;
137
138/* Prints brief summary statistics on stderr. */
139extern void malloc_stats (void) __THROW;
140
141/* Output information about state of allocator to stream FP. */
142extern int malloc_info (int __options, FILE *__fp) __THROW;
143
144/* Hooks for debugging and user-defined versions. */
145extern void (*__MALLOC_HOOK_VOLATILE __free_hook) (void *__ptr,
146 const void *)
147__MALLOC_DEPRECATED;
148extern void *(*__MALLOC_HOOK_VOLATILE __malloc_hook)(size_t __size,
149 const void *)
150__MALLOC_DEPRECATED;
151extern void *(*__MALLOC_HOOK_VOLATILE __realloc_hook)(void *__ptr,
152 size_t __size,
153 const void *)
154__MALLOC_DEPRECATED;
155extern void *(*__MALLOC_HOOK_VOLATILE __memalign_hook)(size_t __alignment,
156 size_t __size,
157 const void *)
158__MALLOC_DEPRECATED;
159extern void (*__MALLOC_HOOK_VOLATILE __after_morecore_hook) (void)
160 __MALLOC_DEPRECATED;
161
162
163__END_DECLS
164#endif /* malloc.h */
165