1/*
2 * Copyright (C) 2008 The Android Open Source Project
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 *  * Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 *  * Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in
12 *    the documentation and/or other materials provided with the
13 *    distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
16 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
18 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
19 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
22 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
25 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29#ifndef _UNISTD_H_
30#define _UNISTD_H_
31
32#include <stddef.h>
33#include <sys/cdefs.h>
34#include <sys/types.h>
35#include <sys/select.h>
36#include <sys/sysconf.h>
37
38#include <bits/lockf.h>
39#include <bits/posix_limits.h>
40
41__BEGIN_DECLS
42
43#define STDIN_FILENO	0
44#define STDOUT_FILENO	1
45#define STDERR_FILENO	2
46
47#define F_OK 0
48#define X_OK 1
49#define W_OK 2
50#define R_OK 4
51
52#define SEEK_SET 0
53#define SEEK_CUR 1
54#define SEEK_END 2
55
56#define _PC_FILESIZEBITS 0
57#define _PC_LINK_MAX 1
58#define _PC_MAX_CANON 2
59#define _PC_MAX_INPUT 3
60#define _PC_NAME_MAX 4
61#define _PC_PATH_MAX 5
62#define _PC_PIPE_BUF 6
63#define _PC_2_SYMLINKS 7
64#define _PC_ALLOC_SIZE_MIN 8
65#define _PC_REC_INCR_XFER_SIZE 9
66#define _PC_REC_MAX_XFER_SIZE 10
67#define _PC_REC_MIN_XFER_SIZE 11
68#define _PC_REC_XFER_ALIGN 12
69#define _PC_SYMLINK_MAX 13
70#define _PC_CHOWN_RESTRICTED 14
71#define _PC_NO_TRUNC 15
72#define _PC_VDISABLE 16
73#define _PC_ASYNC_IO 17
74#define _PC_PRIO_IO 18
75#define _PC_SYNC_IO 19
76
77extern char** environ;
78
79extern __noreturn void _exit(int __status);
80
81extern pid_t  fork(void);
82extern pid_t  vfork(void);
83extern pid_t  getpid(void);
84extern pid_t  gettid(void) __pure2;
85extern pid_t  getpgid(pid_t __pid);
86extern int    setpgid(pid_t __pid, pid_t __pgid);
87extern pid_t  getppid(void);
88extern pid_t  getpgrp(void);
89extern int    setpgrp(void);
90extern pid_t  getsid(pid_t __pid) __INTRODUCED_IN(21);
91extern pid_t  setsid(void);
92
93extern int execv(const char* __path, char* const* __argv);
94extern int execvp(const char* __file, char* const* __argv);
95extern int execvpe(const char* __file, char* const* __argv, char* const* __envp)
96  __INTRODUCED_IN(21);
97extern int execve(const char* __file, char* const* __argv, char* const* __envp);
98extern int execl(const char* __path, const char* __arg0, ...);
99extern int execlp(const char* __file, const char* __arg0, ...);
100extern int execle(const char* __path, const char* __arg0, ...);
101
102extern int nice(int __incr);
103
104extern int setuid(uid_t __uid);
105extern uid_t getuid(void);
106extern int seteuid(uid_t __uid);
107extern uid_t geteuid(void);
108extern int setgid(gid_t __gid);
109extern gid_t getgid(void);
110extern int setegid(gid_t __gid);
111extern gid_t getegid(void);
112extern int getgroups(int __size, gid_t* __list);
113extern int setgroups(size_t __size, const gid_t* __list);
114extern int setreuid(uid_t __ruid, uid_t __euid);
115extern int setregid(gid_t __rgid, gid_t __egid);
116extern int setresuid(uid_t __ruid, uid_t __euid, uid_t __suid);
117extern int setresgid(gid_t __rgid, gid_t __egid, gid_t __sgid);
118extern int getresuid(uid_t* __ruid, uid_t* __euid, uid_t* __suid);
119extern int getresgid(gid_t* __rgid, gid_t* __egid, gid_t* __sgid);
120extern char* getlogin(void);
121
122extern long fpathconf(int __fd, int __name);
123extern long pathconf(const char* __path, int __name);
124
125extern int access(const char* __path, int __mode);
126extern int faccessat(int __dirfd, const char* __path, int __mode, int __flags)
127  __INTRODUCED_IN(21);
128extern int link(const char* __oldpath, const char* __newpath);
129extern int linkat(int __olddirfd, const char* __oldpath, int __newdirfd,
130                  const char* __newpath, int __flags) __INTRODUCED_IN(21);
131extern int unlink(const char* __path);
132extern int unlinkat(int __dirfd, const char* __path, int __flags);
133extern int chdir(const char* __path);
134extern int fchdir(int __fd);
135extern int rmdir(const char* __path);
136extern int pipe(int* __pipefd);
137#if defined(__USE_GNU)
138extern int pipe2(int* __pipefd, int __flags) __INTRODUCED_IN(9);
139#endif
140extern int chroot(const char* __path);
141extern int symlink(const char* __oldpath, const char* __newpath);
142extern int symlinkat(const char* __oldpath, int __newdirfd,
143                     const char* __newpath) __INTRODUCED_IN(21);
144extern ssize_t readlink(const char* __path, char* __buf, size_t __bufsiz);
145extern ssize_t readlinkat(int __dirfd, const char* __path, char* __buf,
146                          size_t __bufsiz) __INTRODUCED_IN(21);
147extern int chown(const char* __path, uid_t __owner, gid_t __group);
148extern int fchown(int __fd, uid_t __owner, gid_t __group);
149extern int fchownat(int __dirfd, const char* __path, uid_t __owner,
150                    gid_t __group, int __flags);
151extern int lchown(const char* __path, uid_t __owner, gid_t __group);
152extern char* getcwd(char* __buf, size_t __size);
153
154extern int sync(void);
155
156extern int close(int __fd);
157
158extern ssize_t read(int __fd, void* __buf, size_t __count);
159extern ssize_t write(int __fd, const void* __buf, size_t __count);
160
161extern int dup(int __oldfd);
162extern int dup2(int __oldfd, int __newfd);
163extern int dup3(int __oldfd, int __newfd, int __flags) __INTRODUCED_IN(21);
164extern int fcntl(int __fd, int __cmd, ...);
165extern int ioctl(int __fd, int __request, ...);
166extern int fsync(int __fd);
167extern int fdatasync(int __fd) __INTRODUCED_IN(9);
168
169#if defined(__USE_FILE_OFFSET64)
170extern off_t lseek(int __fd, off_t __offset, int __whence) __RENAME(lseek64);
171#else
172extern off_t lseek(int __fd, off_t __offset, int __whence);
173#endif
174
175extern off64_t lseek64(int __fd, off64_t __offset, int __whence);
176
177#if defined(__USE_FILE_OFFSET64) && __ANDROID_API__ >= 21
178extern int truncate(const char* __path, off_t __length) __RENAME(truncate64);
179extern ssize_t pread(int __fd, void* __buf, size_t __count, off_t __offset)
180  __RENAME(pread64);
181extern ssize_t pwrite(int __fd, const void* __buf, size_t __count,
182                      off_t __offset) __RENAME(pwrite64);
183extern int ftruncate(int __fd, off_t __length) __RENAME(ftruncate64);
184#else
185extern int truncate(const char* __path, off_t __length);
186extern ssize_t pread(int __fd, void* __buf, size_t __count, off_t __offset);
187extern ssize_t pwrite(int __fd, const void* __buf, size_t __count,
188                      off_t __offset);
189extern int ftruncate(int __fd, off_t __length);
190#endif
191
192extern int truncate64(const char* __path, off64_t __length) __INTRODUCED_IN(21);
193extern ssize_t pread64(int __fd, void* __buf, size_t __count, off64_t __offset) __INTRODUCED_IN(21);
194extern ssize_t pwrite64(int __fd, const void* __buf, size_t __count,
195                        off64_t __offset) __INTRODUCED_IN(21);
196extern int ftruncate64(int __fd, off64_t __length) __INTRODUCED_IN(21);
197
198extern int pause(void);
199extern unsigned int alarm(unsigned int __seconds);
200extern unsigned int sleep(unsigned int __seconds);
201extern int usleep(useconds_t __usec);
202
203int gethostname(char* __name, size_t __len);
204int sethostname(const char* __name, size_t __len);
205
206extern void* __brk(void* __addr);
207extern int brk(void* __addr);
208extern void* sbrk(ptrdiff_t __increment);
209
210extern int getopt(int __argc, char* const* __argv, const char* __argstring);
211extern char* optarg;
212extern int optind, opterr, optopt;
213
214extern int isatty(int __fd);
215extern char* ttyname(int __fd);
216extern int ttyname_r(int __fd, char* __buf, size_t __buflen) __INTRODUCED_IN(8);
217
218extern int acct(const char* __filepath);
219
220long sysconf(int __name);
221
222#if __ANDROID_API__ >= 21
223int getpagesize(void);
224#else
225__inline__ int getpagesize(void) {
226  return sysconf(_SC_PAGESIZE);
227}
228#endif
229
230long syscall(long __number, ...);
231
232extern int daemon(int __nochdir, int __noclose);
233
234#if defined(__arm__) || (defined(__mips__) && !defined(__LP64__))
235extern int cacheflush(long __addr, long __nbytes, long __cache);
236    /* __attribute__((deprecated("use __builtin___clear_cache instead"))); */
237#endif
238
239extern pid_t tcgetpgrp(int __fd);
240extern int tcsetpgrp(int __fd, pid_t __pid);
241
242/* Used to retry syscalls that can return EINTR. */
243#define TEMP_FAILURE_RETRY(exp) ({         \
244    __typeof__(exp) _rc;                   \
245    do {                                   \
246        _rc = (exp);                       \
247    } while (_rc == -1 && errno == EINTR); \
248    _rc; })
249
250/* TODO(unified-headers): Factor out all the FORTIFY features. */
251extern char* __getcwd_chk(char*, size_t, size_t);
252__errordecl(__getcwd_dest_size_error, "getcwd called with size bigger than destination");
253extern char* __getcwd_real(char*, size_t) __RENAME(getcwd);
254
255extern ssize_t __pread_chk(int, void*, size_t, off_t, size_t);
256__errordecl(__pread_dest_size_error, "pread called with size bigger than destination");
257__errordecl(__pread_count_toobig_error, "pread called with count > SSIZE_MAX");
258extern ssize_t __pread_real(int, void*, size_t, off_t) __RENAME(pread);
259
260extern ssize_t __pread64_chk(int, void*, size_t, off64_t, size_t);
261__errordecl(__pread64_dest_size_error, "pread64 called with size bigger than destination");
262__errordecl(__pread64_count_toobig_error, "pread64 called with count > SSIZE_MAX");
263extern ssize_t __pread64_real(int, void*, size_t, off64_t) __RENAME(pread64);
264
265extern ssize_t __pwrite_chk(int, const void*, size_t, off_t, size_t);
266__errordecl(__pwrite_dest_size_error, "pwrite called with size bigger than destination");
267__errordecl(__pwrite_count_toobig_error, "pwrite called with count > SSIZE_MAX");
268extern ssize_t __pwrite_real(int, const void*, size_t, off_t) __RENAME(pwrite);
269
270extern ssize_t __pwrite64_chk(int, const void*, size_t, off64_t, size_t);
271__errordecl(__pwrite64_dest_size_error, "pwrite64 called with size bigger than destination");
272__errordecl(__pwrite64_count_toobig_error, "pwrite64 called with count > SSIZE_MAX");
273extern ssize_t __pwrite64_real(int, const void*, size_t, off64_t) __RENAME(pwrite64);
274
275extern ssize_t __read_chk(int, void*, size_t, size_t);
276__errordecl(__read_dest_size_error, "read called with size bigger than destination");
277__errordecl(__read_count_toobig_error, "read called with count > SSIZE_MAX");
278extern ssize_t __read_real(int, void*, size_t) __RENAME(read);
279
280extern ssize_t __write_chk(int, const void*, size_t, size_t);
281__errordecl(__write_dest_size_error, "write called with size bigger than destination");
282__errordecl(__write_count_toobig_error, "write called with count > SSIZE_MAX");
283extern ssize_t __write_real(int, const void*, size_t) __RENAME(write);
284
285extern ssize_t __readlink_chk(const char*, char*, size_t, size_t);
286__errordecl(__readlink_dest_size_error, "readlink called with size bigger than destination");
287__errordecl(__readlink_size_toobig_error, "readlink called with size > SSIZE_MAX");
288extern ssize_t __readlink_real(const char*, char*, size_t) __RENAME(readlink);
289
290extern ssize_t __readlinkat_chk(int dirfd, const char*, char*, size_t, size_t);
291__errordecl(__readlinkat_dest_size_error, "readlinkat called with size bigger than destination");
292__errordecl(__readlinkat_size_toobig_error, "readlinkat called with size > SSIZE_MAX");
293extern ssize_t __readlinkat_real(int dirfd, const char*, char*, size_t) __RENAME(readlinkat);
294
295#if defined(__BIONIC_FORTIFY)
296
297__BIONIC_FORTIFY_INLINE
298char* getcwd(char* buf, size_t size) {
299    size_t bos = __bos(buf);
300
301#if defined(__clang__)
302    /*
303     * Work around LLVM's incorrect __builtin_object_size implementation here
304     * to avoid needing the workaround in the __getcwd_chk ABI forever.
305     *
306     * https://llvm.org/bugs/show_bug.cgi?id=23277
307     */
308    if (buf == NULL) {
309        bos = __BIONIC_FORTIFY_UNKNOWN_SIZE;
310    }
311#else
312    if (bos == __BIONIC_FORTIFY_UNKNOWN_SIZE) {
313        return __getcwd_real(buf, size);
314    }
315
316    if (__builtin_constant_p(size) && (size > bos)) {
317        __getcwd_dest_size_error();
318    }
319
320    if (__builtin_constant_p(size) && (size <= bos)) {
321        return __getcwd_real(buf, size);
322    }
323#endif
324
325    return __getcwd_chk(buf, size, bos);
326}
327
328#if defined(__USE_FILE_OFFSET64)
329#define __PREAD_PREFIX(x) __pread64_ ## x
330#else
331#define __PREAD_PREFIX(x) __pread_ ## x
332#endif
333
334__BIONIC_FORTIFY_INLINE
335ssize_t pread(int fd, void* buf, size_t count, off_t offset) {
336    size_t bos = __bos0(buf);
337
338#if !defined(__clang__)
339    if (__builtin_constant_p(count) && (count > SSIZE_MAX)) {
340        __PREAD_PREFIX(count_toobig_error)();
341    }
342
343    if (bos == __BIONIC_FORTIFY_UNKNOWN_SIZE) {
344        return __PREAD_PREFIX(real)(fd, buf, count, offset);
345    }
346
347    if (__builtin_constant_p(count) && (count > bos)) {
348        __PREAD_PREFIX(dest_size_error)();
349    }
350
351    if (__builtin_constant_p(count) && (count <= bos)) {
352        return __PREAD_PREFIX(real)(fd, buf, count, offset);
353    }
354#endif
355
356    return __PREAD_PREFIX(chk)(fd, buf, count, offset, bos);
357}
358
359__BIONIC_FORTIFY_INLINE
360ssize_t pread64(int fd, void* buf, size_t count, off64_t offset) {
361    size_t bos = __bos0(buf);
362
363#if !defined(__clang__)
364    if (__builtin_constant_p(count) && (count > SSIZE_MAX)) {
365        __pread64_count_toobig_error();
366    }
367
368    if (bos == __BIONIC_FORTIFY_UNKNOWN_SIZE) {
369        return __pread64_real(fd, buf, count, offset);
370    }
371
372    if (__builtin_constant_p(count) && (count > bos)) {
373        __pread64_dest_size_error();
374    }
375
376    if (__builtin_constant_p(count) && (count <= bos)) {
377        return __pread64_real(fd, buf, count, offset);
378    }
379#endif
380
381    return __pread64_chk(fd, buf, count, offset, bos);
382}
383
384#if defined(__USE_FILE_OFFSET64)
385#define __PWRITE_PREFIX(x) __pwrite64_ ## x
386#else
387#define __PWRITE_PREFIX(x) __pwrite_ ## x
388#endif
389
390__BIONIC_FORTIFY_INLINE
391ssize_t pwrite(int fd, const void* buf, size_t count, off_t offset) {
392    size_t bos = __bos0(buf);
393
394#if !defined(__clang__)
395    if (__builtin_constant_p(count) && (count > SSIZE_MAX)) {
396        __PWRITE_PREFIX(count_toobig_error)();
397    }
398
399    if (bos == __BIONIC_FORTIFY_UNKNOWN_SIZE) {
400        return __PWRITE_PREFIX(real)(fd, buf, count, offset);
401    }
402
403    if (__builtin_constant_p(count) && (count > bos)) {
404        __PWRITE_PREFIX(dest_size_error)();
405    }
406
407    if (__builtin_constant_p(count) && (count <= bos)) {
408        return __PWRITE_PREFIX(real)(fd, buf, count, offset);
409    }
410#endif
411
412    return __PWRITE_PREFIX(chk)(fd, buf, count, offset, bos);
413}
414
415__BIONIC_FORTIFY_INLINE
416ssize_t pwrite64(int fd, const void* buf, size_t count, off64_t offset) {
417    size_t bos = __bos0(buf);
418
419#if !defined(__clang__)
420    if (__builtin_constant_p(count) && (count > SSIZE_MAX)) {
421        __pwrite64_count_toobig_error();
422    }
423
424    if (bos == __BIONIC_FORTIFY_UNKNOWN_SIZE) {
425        return __pwrite64_real(fd, buf, count, offset);
426    }
427
428    if (__builtin_constant_p(count) && (count > bos)) {
429        __pwrite64_dest_size_error();
430    }
431
432    if (__builtin_constant_p(count) && (count <= bos)) {
433        return __pwrite64_real(fd, buf, count, offset);
434    }
435#endif
436
437    return __pwrite64_chk(fd, buf, count, offset, bos);
438}
439
440__BIONIC_FORTIFY_INLINE
441ssize_t read(int fd, void* buf, size_t count) {
442    size_t bos = __bos0(buf);
443
444#if !defined(__clang__)
445    if (__builtin_constant_p(count) && (count > SSIZE_MAX)) {
446        __read_count_toobig_error();
447    }
448
449    if (bos == __BIONIC_FORTIFY_UNKNOWN_SIZE) {
450        return __read_real(fd, buf, count);
451    }
452
453    if (__builtin_constant_p(count) && (count > bos)) {
454        __read_dest_size_error();
455    }
456
457    if (__builtin_constant_p(count) && (count <= bos)) {
458        return __read_real(fd, buf, count);
459    }
460#endif
461
462    return __read_chk(fd, buf, count, bos);
463}
464
465__BIONIC_FORTIFY_INLINE
466ssize_t write(int fd, const void* buf, size_t count) {
467    size_t bos = __bos0(buf);
468
469#if !defined(__clang__)
470#if 0 /* work around a false positive due to a missed optimization */
471    if (__builtin_constant_p(count) && (count > SSIZE_MAX)) {
472        __write_count_toobig_error();
473    }
474#endif
475
476    if (bos == __BIONIC_FORTIFY_UNKNOWN_SIZE) {
477        return __write_real(fd, buf, count);
478    }
479
480    if (__builtin_constant_p(count) && (count > bos)) {
481        __write_dest_size_error();
482    }
483
484    if (__builtin_constant_p(count) && (count <= bos)) {
485        return __write_real(fd, buf, count);
486    }
487#endif
488
489    return __write_chk(fd, buf, count, bos);
490}
491
492__BIONIC_FORTIFY_INLINE
493ssize_t readlink(const char* path, char* buf, size_t size) {
494    size_t bos = __bos(buf);
495
496#if !defined(__clang__)
497    if (__builtin_constant_p(size) && (size > SSIZE_MAX)) {
498        __readlink_size_toobig_error();
499    }
500
501    if (bos == __BIONIC_FORTIFY_UNKNOWN_SIZE) {
502        return __readlink_real(path, buf, size);
503    }
504
505    if (__builtin_constant_p(size) && (size > bos)) {
506        __readlink_dest_size_error();
507    }
508
509    if (__builtin_constant_p(size) && (size <= bos)) {
510        return __readlink_real(path, buf, size);
511    }
512#endif
513
514    return __readlink_chk(path, buf, size, bos);
515}
516
517__BIONIC_FORTIFY_INLINE
518ssize_t readlinkat(int dirfd, const char* path, char* buf, size_t size) {
519    size_t bos = __bos(buf);
520
521#if !defined(__clang__)
522    if (__builtin_constant_p(size) && (size > SSIZE_MAX)) {
523        __readlinkat_size_toobig_error();
524    }
525
526    if (bos == __BIONIC_FORTIFY_UNKNOWN_SIZE) {
527        return __readlinkat_real(dirfd, path, buf, size);
528    }
529
530    if (__builtin_constant_p(size) && (size > bos)) {
531        __readlinkat_dest_size_error();
532    }
533
534    if (__builtin_constant_p(size) && (size <= bos)) {
535        return __readlinkat_real(dirfd, path, buf, size);
536    }
537#endif
538
539    return __readlinkat_chk(dirfd, path, buf, size, bos);
540}
541
542#endif /* defined(__BIONIC_FORTIFY) */
543
544__END_DECLS
545
546#endif /* _UNISTD_H_ */
547