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
118
|
/* SPDX-License-Identifier: GPL-3.0-or-later */
/*
* util.h
*
* Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
*/
#ifndef UTIL_H
#define UTIL_H
#include "config.h"
#include <sys/types.h>
#include <stdint.h>
#include <stddef.h>
#if defined(__GNUC__) || defined(__clang__)
#define UI_ADD_OV __builtin_uadd_overflow
#define UL_ADD_OV __builtin_uaddl_overflow
#define ULL_ADD_OV __builtin_uaddll_overflow
#define UI_MUL_OV __builtin_umul_overflow
#define UL_MUL_OV __builtin_umull_overflow
#define ULL_MUL_OV __builtin_umulll_overflow
#else
#error Sorry, I do not know how to trap integer overflows with this compiler
#endif
#if SIZEOF_SIZE_T <= SIZEOF_INT
#define SZ_ADD_OV UI_ADD_OV
#define SZ_MUL_OV UI_MUL_OV
#elif SIZEOF_SIZE_T == SIZEOF_LONG
#define SZ_ADD_OV UL_ADD_OV
#define SZ_MUL_OV UL_MUL_OV
#elif SIZEOF_SIZE_T == SIZEOF_LONG_LONG
#define SZ_ADD_OV ULL_ADD_OV
#define SZ_MUL_OV ULL_MUL_OV
#else
#error Cannot determine maximum value of size_t
#endif
/* layout structure for sparse files, indicating where the actual data is */
typedef struct sparse_map_t {
struct sparse_map_t *next;
uint64_t offset;
uint64_t count;
} sparse_map_t;
/*
A wrapper around the write() system call. It retries the write if it is
interrupted by a signal or only part of the data was written. Returns 0
on success. Writes to stderr on failure using 'errstr' as a perror style
error prefix.
*/
int write_data(const char *errstr, int fd, const void *data, size_t size);
/*
A wrapper around the read() system call. It retries the read if it is
interrupted by a signal or less than the desired size was read. Returns 0
on success. Writes to stderr on failure using 'errstr' as a perror style
error prefix.
*/
int read_data(const char *errstr, int fd, void *buffer, size_t size);
/*
Similar to read_data but wrapps pread() instead of read().
*/
int read_data_at(const char *errstr, off_t location,
int fd, void *buffer, size_t size);
/*
A common implementation of the '--version' command line flag.
Prints out version information. The program name is extracted from the
BSD style __progname global variable.
*/
void print_version(void);
/*
A wrapper around mkdir() that behaves like 'mkdir -p'. It tries to create
every component of the given path and skips already existing entries.
Returns 0 on success.
*/
int mkdir_p(const char *path);
/* Returns 0 on success. On failure, prints error message to stderr. */
int pushd(const char *path);
/* Same as pushd, but the string doesn't have to be null-terminated. */
int pushdn(const char *path, size_t len);
/* Returns 0 on success. On failure, prints error message to stderr. */
int popd(void);
/*
Write zero bytes to an output file to padd it to specified block size.
Returns 0 on success. On failure, prints error message to stderr.
*/
int padd_file(int outfd, uint64_t size, size_t blocksize);
/*
Helper for allocating data structures with flexible array members.
'base_size' is the size of the struct itself, 'item_size' the size of a
single array element and 'nmemb' the number of elements.
Iternally checks for arithmetic overflows when allocating the combined thing.
*/
void *alloc_flex(size_t base_size, size_t item_size, size_t nmemb);
/* Basically the same as calloc, but *ALWAYS* does overflow checking */
void *alloc_array(size_t item_size, size_t nmemb);
/* allocates len + 1 (for the null-terminator) and does overflow checking */
void *alloc_string(size_t len);
#endif /* UTIL_H */
|
