1 /* SPDX-License-Identifier: GPL-2.0+ OR BSD-3-Clause */
2 /*
3 * Copyright (c) Facebook, Inc.
4 * All rights reserved.
5 *
6 * This source code is licensed under both the BSD-style license (found in the
7 * LICENSE file in the root directory of this source tree) and the GPLv2 (found
8 * in the COPYING file in the root directory of this source tree).
9 * You may select, at your option, one of the above-listed licenses.
10 */
11
12 /*
13 * This file provides common libc dependencies that zstd requires.
14 * The purpose is to allow replacing this file with a custom implementation
15 * to compile zstd without libc support.
16 */
17
18 /* Need:
19 * NULL
20 * INT_MAX
21 * UINT_MAX
22 * ZSTD_memcpy()
23 * ZSTD_memset()
24 * ZSTD_memmove()
25 */
26 #ifndef ZSTD_DEPS_COMMON
27 #define ZSTD_DEPS_COMMON
28
29 #include <linux/limits.h>
30 #include <linux/stddef.h>
31
32 #define ZSTD_memcpy(d,s,n) __builtin_memcpy((d),(s),(n))
33 #define ZSTD_memmove(d,s,n) __builtin_memmove((d),(s),(n))
34 #define ZSTD_memset(d,s,n) __builtin_memset((d),(s),(n))
35
36 #endif /* ZSTD_DEPS_COMMON */
37
38 /*
39 * Define malloc as always failing. That means the user must
40 * either use ZSTD_customMem or statically allocate memory.
41 * Need:
42 * ZSTD_malloc()
43 * ZSTD_free()
44 * ZSTD_calloc()
45 */
46 #ifdef ZSTD_DEPS_NEED_MALLOC
47 #ifndef ZSTD_DEPS_MALLOC
48 #define ZSTD_DEPS_MALLOC
49
50 #define ZSTD_malloc(s) ({ (void)(s); NULL; })
51 #define ZSTD_free(p) ((void)(p))
52 #define ZSTD_calloc(n,s) ({ (void)(n); (void)(s); NULL; })
53
54 #endif /* ZSTD_DEPS_MALLOC */
55 #endif /* ZSTD_DEPS_NEED_MALLOC */
56
57 /*
58 * Provides 64-bit math support.
59 * Need:
60 * U64 ZSTD_div64(U64 dividend, U32 divisor)
61 */
62 #ifdef ZSTD_DEPS_NEED_MATH64
63 #ifndef ZSTD_DEPS_MATH64
64 #define ZSTD_DEPS_MATH64
65
66 #include <linux/math64.h>
67
ZSTD_div64(uint64_t dividend,uint32_t divisor)68 static uint64_t ZSTD_div64(uint64_t dividend, uint32_t divisor) {
69 return div_u64(dividend, divisor);
70 }
71
72 #endif /* ZSTD_DEPS_MATH64 */
73 #endif /* ZSTD_DEPS_NEED_MATH64 */
74
75 /*
76 * This is only requested when DEBUGLEVEL >= 1, meaning
77 * it is disabled in production.
78 * Need:
79 * assert()
80 */
81 #ifdef ZSTD_DEPS_NEED_ASSERT
82 #ifndef ZSTD_DEPS_ASSERT
83 #define ZSTD_DEPS_ASSERT
84
85 #include <linux/kernel.h>
86
87 #define assert(x) WARN_ON(!(x))
88
89 #endif /* ZSTD_DEPS_ASSERT */
90 #endif /* ZSTD_DEPS_NEED_ASSERT */
91
92 /*
93 * This is only requested when DEBUGLEVEL >= 2, meaning
94 * it is disabled in production.
95 * Need:
96 * ZSTD_DEBUG_PRINT()
97 */
98 #ifdef ZSTD_DEPS_NEED_IO
99 #ifndef ZSTD_DEPS_IO
100 #define ZSTD_DEPS_IO
101
102 #include <linux/printk.h>
103
104 #define ZSTD_DEBUG_PRINT(...) pr_debug(__VA_ARGS__)
105
106 #endif /* ZSTD_DEPS_IO */
107 #endif /* ZSTD_DEPS_NEED_IO */
108
