aboutsummaryrefslogtreecommitdiff
path: root/lib/portability.h
blob: 0404c85ecea981c13dacfb468e72ae0504012bbd (plain)
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
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
// Workarounds for horrible build environment idiosyncrasies.

// Instead of polluting the code with strange #ifdefs to work around bugs
// in specific compiler, library, or OS versions, localize all that here
// and in portability.c

// For musl
#define _ALL_SOURCE

// Test for gcc (using compiler builtin #define)

#ifdef __GNUC__
#define noreturn	__attribute__((noreturn))
#define printf_format	__attribute__((format(printf, 1, 2)))
#else
#define noreturn
#define printf_format
#endif

// Always use long file support.
#define _FILE_OFFSET_BITS 64

// This isn't in the spec, but it's how we determine what libc we're using.

#include <features.h>

// Types various replacement prototypes need
#include <sys/types.h>

// Various constants old build environments might not have even if kernel does

#ifndef AT_FDCWD
#define AT_FDCWD -100
#endif

#ifndef AT_SYMLINK_NOFOLLOW
#define AT_SYMLINK_NOFOLLOW 0x100
#endif

#ifndef AT_REMOVEDIR
#define AT_REMOVEDIR 0x200
#endif

#ifndef RLIMIT_RTTIME
#define RLIMIT_RTTIME 15
#endif

// Introduced in Linux 3.1
#ifndef SEEK_DATA
#define SEEK_DATA 3
#endif
#ifndef SEEK_HOLE
#define SEEK_HOLE 4
#endif

// We don't define GNU_dammit because we're not part of the gnu project, and
// don't want to get any FSF on us. Unfortunately glibc (gnu libc)
// won't give us Linux syscall wrappers without claiming to be part of the
// gnu project (because Stallman's "GNU owns Linux" revisionist history
// crusade includes the kernel, even though Linux was inspired by Minix).

// We use most non-posix Linux syscalls directly through the syscall() wrapper,
// but even many posix-2008 functions aren't provided by glibc unless you
// claim it's in the name of Gnu.

#if defined(__GLIBC__)
// "Function prototypes shall be provided." but aren't.
// http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/unistd.h.html
char *crypt(const char *key, const char *salt);

// According to posix, #include header, get a function definition. But glibc...
// http://pubs.opengroup.org/onlinepubs/9699919799/functions/wcwidth.html
#include <wchar.h>
int wcwidth(wchar_t wc);

// see http://pubs.opengroup.org/onlinepubs/9699919799/functions/strptime.html
#include <time.h>
char *strptime(const char *buf, const char *format, struct tm *tm);

// They didn't like posix basename so they defined another function with the
// same name and if you include libgen.h it #defines basename to something
// else (where they implemented the real basename), and that define breaks
// the table entry for the basename command. They didn't make a new function
// with a different name for their new behavior because gnu.
//
// Solution: don't use their broken header, provide an inline to redirect the
// correct name to the broken name.

char *dirname(char *path);
char *__xpg_basename(char *path);
static inline char *basename(char *path) { return __xpg_basename(path); }

// When building under obsolete glibc (Ubuntu 8.04-ish), hold its hand a bit.
#if __GLIBC__ == 2 && __GLIBC_MINOR__ < 10
#define fstatat fstatat64
int fstatat64(int dirfd, const char *pathname, void *buf, int flags);
int readlinkat(int dirfd, const char *pathname, char *buf, size_t bufsiz);
char *stpcpy(char *dest, const char *src);
#include <sys/stat.h>
int fchmodat(int dirfd, const char *pathname, mode_t mode, int flags);
int openat(int dirfd, const char *pathname, int flags, ...);
#include <dirent.h>
DIR *fdopendir(int fd);
#include <unistd.h>
int fchownat(int dirfd, const char *pathname,
                    uid_t owner, gid_t group, int flags);
int isblank(int c);
int unlinkat(int dirfd, const char *pathname, int flags);
#include <stdio.h>
ssize_t getdelim(char **lineptr, size_t *n, int delim, FILE *stream);

// Straight from posix-2008, things old glibc had but didn't prototype

int faccessat(int fd, const char *path, int amode, int flag);
int linkat(int fd1, const char *path1, int fd2, const char *path2, int flag);
int mkdirat(int fd, const char *path, mode_t mode);
int symlinkat(const char *path1, int fd, const char *path2);
int mknodat(int fd, const char *path, mode_t mode, dev_t dev);
#include <sys/time.h>
int futimens(int fd, const struct timespec times[2]);
int utimensat(int fd, const char *path, const struct timespec times[2], int flag);

#ifndef MNT_DETACH
#define MNT_DETACH 2
#endif
#endif // Old glibc

#endif // glibc in general

#if !defined(__GLIBC__)
// POSIX basename.
#include <libgen.h>
#endif

// Work out how to do endianness

#ifndef __APPLE__
#include <byteswap.h>
#include <endian.h>

#if __BYTE_ORDER == __BIG_ENDIAN
#define IS_BIG_ENDIAN 1
#else
#define IS_BIG_ENDIAN 0
#endif

int clearenv(void);
#else

#ifdef __BIG_ENDIAN__
#define IS_BIG_ENDIAN 1
#else
#define IS_BIG_ENDIAN 0
#endif

#endif

#if IS_BIG_ENDIAN
#define IS_LITTLE_ENDIAN 0
#define SWAP_BE16(x) (x)
#define SWAP_BE32(x) (x)
#define SWAP_BE64(x) (x)
#define SWAP_LE16(x) bswap_16(x)
#define SWAP_LE32(x) bswap_32(x)
#define SWAP_LE64(x) bswap_64(x)
#else
#define IS_LITTLE_ENDIAN 1
#define SWAP_BE16(x) bswap_16(x)
#define SWAP_BE32(x) bswap_32(x)
#define SWAP_BE64(x) bswap_64(x)
#define SWAP_LE16(x) (x)
#define SWAP_LE32(x) (x)
#define SWAP_LE64(x) (x)
#endif

#if defined(__APPLE__) \
    || (defined(__GLIBC__) && __GLIBC__ == 2 && __GLIBC_MINOR__ < 10)
ssize_t getdelim(char **lineptr, size_t *n, int delim, FILE *stream);
ssize_t getline(char **lineptr, size_t *n, FILE *stream);
#endif

// Linux headers not listed by POSIX or LSB
#include <sys/mount.h>
#include <sys/swap.h>

// Android is missing some headers and functions
// "generated/config.h" is included first
#if CFG_TOYBOX_SHADOW
#include <shadow.h>
#endif
#if CFG_TOYBOX_UTMPX
#include <utmpx.h>
#else
struct utmpx {int ut_type;};
#define USER_PROCESS 0
static inline struct utmpx *getutxent(void) {return 0;}
static inline void setutxent(void) {;}
static inline void endutxent(void) {;}
#endif

// Some systems don't define O_NOFOLLOW, and it varies by architecture, so...
#include <fcntl.h>
#ifndef O_NOFOLLOW
#define O_NOFOLLOW 0
#endif
#ifndef O_NOATIME
#define O_NOATIME 01000000
#endif
#ifndef O_CLOEXEC
#define O_CLOEXEC 02000000
#endif
#ifndef O_PATH
#define O_PATH   010000000
#endif
#ifndef SCHED_RESET_ON_FORK
#define SCHED_RESET_ON_FORK (1<<30)
#endif

// Glibc won't give you linux-kernel constants unless you say "no, a BUD lite"
// even though linux has nothing to do with the FSF and never has.
#ifndef F_SETPIPE_SZ
#define F_SETPIPE_SZ 1031
#endif

#ifndef F_GETPIPE_SZ
#define F_GETPIPE_SZ 1032
#endif

#if defined(__SIZEOF_DOUBLE__) && defined(__SIZEOF_LONG__) \
    && __SIZEOF_DOUBLE__ <= __SIZEOF_LONG__
typedef double FLOAT;
#else
typedef float FLOAT;
#endif

#ifndef __uClinux__
pid_t xfork(void);
#endif

//#define strncpy(...) @@strncpyisbadmmkay@@
//#define strncat(...) @@strncatisbadmmkay@@

#if CFG_TOYBOX_ANDROID_SCHEDPOLICY
#include <cutils/sched_policy.h>
#else
static inline int get_sched_policy(int tid, void *policy) {return 0;}
static inline char *get_sched_policy_name(int policy) {return "unknown";}
#endif

#ifndef SYSLOG_NAMES
typedef struct {char *c_name; int c_val;} CODE;
extern CODE prioritynames[], facilitynames[];
#endif

#if CFG_TOYBOX_GETRANDOM
#include <sys/random.h>
#endif
void xgetrandom(void *buf, unsigned len, unsigned flags);

// android NDK doesn't have confstr
#ifndef _CS_PATH
#define _CS_PATH	0
#define _CS_V7_ENV	1
#include <string.h>
static inline void confstr(int a, char *b, int c) {strcpy(b, a ? "POSIXLY_CORRECT=1" : "/bin:/usr/bin");}
#endif