1 /* vi: set sw=4 ts=4: */
5 * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
6 * Copyright (C) 2006 Rob Landley
7 * Copyright (C) 2006 Denys Vlasenko
9 * Licensed under GPLv2, see file LICENSE in this source tree.
11 /* We need to have separate xfuncs.c and xfuncs_printf.c because
12 * with current linkers, even with section garbage collection,
13 * if *.o module references any of XXXprintf functions, you pull in
14 * entire printf machinery. Even if you do not use the function
15 * which uses XXXprintf.
17 * xfuncs.c contains functions (not necessarily xfuncs)
18 * which do not pull in printf, directly or indirectly.
19 * xfunc_printf.c contains those which do.
24 /* All the functions starting with "x" call bb_error_msg_and_die() if they
25 * fail, so callers never need to check for errors. If it returned, it
28 void FAST_FUNC bb_die_memory_exhausted(void)
30 bb_error_msg_and_die(bb_msg_memory_exhausted);
34 /* dmalloc provides variants of these that do abort() on failure.
35 * Since dmalloc's prototypes overwrite the impls here as they are
36 * included after these prototypes in libbb.h, all is well.
38 // Warn if we can't allocate size bytes of memory.
39 void* FAST_FUNC malloc_or_warn(size_t size)
41 void *ptr = malloc(size);
42 if (ptr == NULL && size != 0)
43 bb_error_msg(bb_msg_memory_exhausted);
47 // Die if we can't allocate size bytes of memory.
48 void* FAST_FUNC xmalloc(size_t size)
50 void *ptr = malloc(size);
51 if (ptr == NULL && size != 0)
52 bb_die_memory_exhausted();
56 // Die if we can't resize previously allocated memory. (This returns a pointer
57 // to the new memory, which may or may not be the same as the old memory.
58 // It'll copy the contents to a new chunk and free the old one if necessary.)
59 void* FAST_FUNC xrealloc(void *ptr, size_t size)
61 ptr = realloc(ptr, size);
62 if (ptr == NULL && size != 0)
63 bb_die_memory_exhausted();
68 // Die if we can't allocate and zero size bytes of memory.
69 void* FAST_FUNC xzalloc(size_t size)
71 void *ptr = xmalloc(size);
76 // Die if we can't copy a string to freshly allocated memory.
77 char* FAST_FUNC xstrdup(const char *s)
87 bb_die_memory_exhausted();
92 // Die if we can't allocate n+1 bytes (space for the null terminator) and copy
93 // the (possibly truncated to length n) string into it.
94 char* FAST_FUNC xstrndup(const char *s, int n)
99 if (ENABLE_DEBUG && s == NULL)
100 bb_error_msg_and_die("xstrndup bug");
102 /* We can just xmalloc(n+1) and strncpy into it, */
103 /* but think about xstrndup("abc", 10000) wastage! */
115 return memcpy(t, s, n);
118 void* FAST_FUNC xmemdup(const void *s, int n)
120 return memcpy(xmalloc(n), s, n);
123 // Die if we can't open a file and return a FILE* to it.
124 // Notice we haven't got xfread(), This is for use with fscanf() and friends.
125 FILE* FAST_FUNC xfopen(const char *path, const char *mode)
127 FILE *fp = fopen(path, mode);
129 bb_perror_msg_and_die("can't open '%s'", path);
133 // Die if we can't open a file and return a fd.
134 int FAST_FUNC xopen3(const char *pathname, int flags, int mode)
138 ret = open(pathname, flags, mode);
140 bb_perror_msg_and_die("can't open '%s'", pathname);
145 // Die if we can't open a file and return a fd.
146 int FAST_FUNC xopen(const char *pathname, int flags)
148 return xopen3(pathname, flags, 0666);
151 // Warn if we can't open a file and return a fd.
152 int FAST_FUNC open3_or_warn(const char *pathname, int flags, int mode)
156 ret = open(pathname, flags, mode);
158 bb_perror_msg("can't open '%s'", pathname);
163 // Warn if we can't open a file and return a fd.
164 int FAST_FUNC open_or_warn(const char *pathname, int flags)
166 return open3_or_warn(pathname, flags, 0666);
169 /* Die if we can't open an existing file readonly with O_NONBLOCK
171 * Note that for ioctl O_RDONLY is sufficient.
173 int FAST_FUNC xopen_nonblocking(const char *pathname)
175 return xopen(pathname, O_RDONLY | O_NONBLOCK);
178 int FAST_FUNC xopen_as_uid_gid(const char *pathname, int flags, uid_t u, gid_t g)
181 uid_t old_euid = geteuid();
182 gid_t old_egid = getegid();
187 fd = xopen(pathname, flags);
195 void FAST_FUNC xunlink(const char *pathname)
197 if (unlink(pathname))
198 bb_perror_msg_and_die("can't remove file '%s'", pathname);
201 void FAST_FUNC xrename(const char *oldpath, const char *newpath)
203 if (rename(oldpath, newpath))
204 bb_perror_msg_and_die("can't move '%s' to '%s'", oldpath, newpath);
207 int FAST_FUNC rename_or_warn(const char *oldpath, const char *newpath)
209 int n = rename(oldpath, newpath);
211 bb_perror_msg("can't move '%s' to '%s'", oldpath, newpath);
215 void FAST_FUNC xpipe(int filedes[2])
218 bb_perror_msg_and_die("can't create pipe");
221 void FAST_FUNC xdup2(int from, int to)
223 if (dup2(from, to) != to)
224 bb_perror_msg_and_die("can't duplicate file descriptor");
227 // "Renumber" opened fd
228 void FAST_FUNC xmove_fd(int from, int to)
236 // Die with an error message if we can't write the entire buffer.
237 void FAST_FUNC xwrite(int fd, const void *buf, size_t count)
240 ssize_t size = full_write(fd, buf, count);
241 if ((size_t)size != count) {
243 * Two cases: write error immediately;
244 * or some writes succeeded, then we hit an error.
245 * In either case, errno is set.
247 bb_perror_msg_and_die(
248 size >= 0 ? "short write" : "write error"
253 void FAST_FUNC xwrite_str(int fd, const char *str)
255 xwrite(fd, str, strlen(str));
258 void FAST_FUNC xclose(int fd)
261 bb_perror_msg_and_die("close failed");
264 // Die with an error message if we can't lseek to the right spot.
265 off_t FAST_FUNC xlseek(int fd, off_t offset, int whence)
267 off_t off = lseek(fd, offset, whence);
268 if (off == (off_t)-1) {
269 if (whence == SEEK_SET)
270 bb_perror_msg_and_die("lseek(%"OFF_FMT"u)", offset);
271 bb_perror_msg_and_die("lseek");
276 int FAST_FUNC xmkstemp(char *template)
278 int fd = mkstemp(template);
280 bb_perror_msg_and_die("can't create temp file '%s'", template);
284 // Die with supplied filename if this FILE* has ferror set.
285 void FAST_FUNC die_if_ferror(FILE *fp, const char *fn)
288 /* ferror doesn't set useful errno */
289 bb_error_msg_and_die("%s: I/O error", fn);
293 // Die with an error message if stdout has ferror set.
294 void FAST_FUNC die_if_ferror_stdout(void)
296 die_if_ferror(stdout, bb_msg_standard_output);
299 int FAST_FUNC fflush_all(void)
305 int FAST_FUNC bb_putchar(int ch)
310 /* Die with an error message if we can't copy an entire FILE* to stdout,
311 * then close that file. */
312 void FAST_FUNC xprint_and_close_file(FILE *file)
315 // copyfd outputs error messages for us.
316 if (bb_copyfd_eof(fileno(file), STDOUT_FILENO) == -1)
322 // Die with an error message if we can't malloc() enough space and do an
323 // sprintf() into that space.
324 char* FAST_FUNC xasprintf(const char *format, ...)
331 r = vasprintf(&string_ptr, format, p);
335 bb_die_memory_exhausted();
339 void FAST_FUNC xsetenv(const char *key, const char *value)
341 if (setenv(key, value, 1))
342 bb_die_memory_exhausted();
345 /* Handles "VAR=VAL" strings, even those which are part of environ
348 void FAST_FUNC bb_unsetenv(const char *var)
350 char onstack[128 - 16]; /* smaller stack setup code on x86 */
353 tp = strchr(var, '=');
355 /* In case var was putenv'ed, we can't replace '='
356 * with NUL and unsetenv(var) - it won't work,
357 * env is modified by the replacement, unsetenv
358 * sees "VAR" instead of "VAR=VAL" and does not remove it!
361 unsigned sz = tp - var;
362 if (sz < sizeof(onstack)) {
363 ((char*)mempcpy(onstack, var, sz))[0] = '\0';
367 /* unlikely: very long var name */
368 var = tp = xstrndup(var, sz);
375 void FAST_FUNC bb_unsetenv_and_free(char *var)
381 // Die with an error message if we can't set gid. (Because resource limits may
382 // limit this user to a given number of processes, and if that fills up the
383 // setgid() will fail and we'll _still_be_root_, which is bad.)
384 void FAST_FUNC xsetgid(gid_t gid)
386 if (setgid(gid)) bb_perror_msg_and_die("setgid");
389 // Die with an error message if we can't set uid. (See xsetgid() for why.)
390 void FAST_FUNC xsetuid(uid_t uid)
392 if (setuid(uid)) bb_perror_msg_and_die("setuid");
395 void FAST_FUNC xsetegid(gid_t egid)
397 if (setegid(egid)) bb_perror_msg_and_die("setegid");
400 void FAST_FUNC xseteuid(uid_t euid)
402 if (seteuid(euid)) bb_perror_msg_and_die("seteuid");
405 // Die if we can't chdir to a new path.
406 void FAST_FUNC xchdir(const char *path)
409 bb_perror_msg_and_die("can't change directory to '%s'", path);
412 void FAST_FUNC xfchdir(int fd)
415 bb_perror_msg_and_die("fchdir");
418 void FAST_FUNC xchroot(const char *path)
421 bb_perror_msg_and_die("can't change root directory to '%s'", path);
425 // Print a warning message if opendir() fails, but don't die.
426 DIR* FAST_FUNC warn_opendir(const char *path)
432 bb_perror_msg("can't open '%s'", path);
436 // Die with an error message if opendir() fails.
437 DIR* FAST_FUNC xopendir(const char *path)
443 bb_perror_msg_and_die("can't open '%s'", path);
447 // Die with an error message if we can't open a new socket.
448 int FAST_FUNC xsocket(int domain, int type, int protocol)
450 int r = socket(domain, type, protocol);
453 /* Hijack vaguely related config option */
454 #if ENABLE_VERBOSE_RESOLUTION_ERRORS
455 const char *s = "INET";
457 if (domain == AF_PACKET) s = "PACKET";
460 if (domain == AF_NETLINK) s = "NETLINK";
462 IF_FEATURE_IPV6(if (domain == AF_INET6) s = "INET6";)
463 bb_perror_msg_and_die("socket(AF_%s,%d,%d)", s, type, protocol);
465 bb_perror_msg_and_die("socket");
472 // Die with an error message if we can't bind a socket to an address.
473 void FAST_FUNC xbind(int sockfd, struct sockaddr *my_addr, socklen_t addrlen)
475 if (bind(sockfd, my_addr, addrlen)) bb_perror_msg_and_die("bind");
478 // Die with an error message if we can't listen for connections on a socket.
479 void FAST_FUNC xlisten(int s, int backlog)
481 if (listen(s, backlog)) bb_perror_msg_and_die("listen");
484 /* Die with an error message if sendto failed.
485 * Return bytes sent otherwise */
486 ssize_t FAST_FUNC xsendto(int s, const void *buf, size_t len, const struct sockaddr *to,
489 ssize_t ret = sendto(s, buf, len, 0, to, tolen);
491 if (ENABLE_FEATURE_CLEAN_UP)
493 bb_perror_msg_and_die("sendto");
498 // xstat() - a stat() which dies on failure with meaningful error message
499 void FAST_FUNC xstat(const char *name, struct stat *stat_buf)
501 if (stat(name, stat_buf))
502 bb_perror_msg_and_die("can't stat '%s'", name);
505 void FAST_FUNC xfstat(int fd, struct stat *stat_buf, const char *errmsg)
507 /* errmsg is usually a file name, but not always:
508 * xfstat may be called in a spot where file name is no longer
509 * available, and caller may give e.g. "can't stat input file" string.
511 if (fstat(fd, stat_buf))
512 bb_simple_perror_msg_and_die(errmsg);
515 // selinux_or_die() - die if SELinux is disabled.
516 void FAST_FUNC selinux_or_die(void)
519 int rc = is_selinux_enabled();
521 bb_error_msg_and_die("SELinux is disabled");
523 bb_error_msg_and_die("is_selinux_enabled() failed");
526 bb_error_msg_and_die("SELinux support is disabled");
530 int FAST_FUNC ioctl_or_perror_and_die(int fd, unsigned request, void *argp, const char *fmt,...)
535 ret = ioctl(fd, request, argp);
538 bb_verror_msg(fmt, p, strerror(errno));
539 /* xfunc_die can actually longjmp, so be nice */
546 int FAST_FUNC ioctl_or_perror(int fd, unsigned request, void *argp, const char *fmt,...)
549 int ret = ioctl(fd, request, argp);
553 bb_verror_msg(fmt, p, strerror(errno));
559 #if ENABLE_IOCTL_HEX2STR_ERROR
560 int FAST_FUNC bb_ioctl_or_warn(int fd, unsigned request, void *argp, const char *ioctl_name)
564 ret = ioctl(fd, request, argp);
566 bb_simple_perror_msg(ioctl_name);
569 int FAST_FUNC bb_xioctl(int fd, unsigned request, void *argp, const char *ioctl_name)
573 ret = ioctl(fd, request, argp);
575 bb_simple_perror_msg_and_die(ioctl_name);
579 int FAST_FUNC bb_ioctl_or_warn(int fd, unsigned request, void *argp)
583 ret = ioctl(fd, request, argp);
585 bb_perror_msg("ioctl %#x failed", request);
588 int FAST_FUNC bb_xioctl(int fd, unsigned request, void *argp)
592 ret = ioctl(fd, request, argp);
594 bb_perror_msg_and_die("ioctl %#x failed", request);
599 char* FAST_FUNC xmalloc_ttyname(int fd)
602 int r = ttyname_r(fd, buf, sizeof(buf) - 1);
608 void FAST_FUNC generate_uuid(uint8_t *buf)
610 /* http://www.ietf.org/rfc/rfc4122.txt
611 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
612 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
614 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
615 * | time_mid | time_hi_and_version |
616 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
617 * |clk_seq_and_variant | node (0-1) |
618 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
620 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
621 * IOW, uuid has this layout:
622 * uint32_t time_low (big endian)
623 * uint16_t time_mid (big endian)
624 * uint16_t time_hi_and_version (big endian)
625 * version is a 4-bit field:
627 * 2 DCE Security, with embedded POSIX UIDs
629 * 4 Randomly generated
630 * 5 Name-based (SHA-1)
631 * uint16_t clk_seq_and_variant (big endian)
632 * variant is a 3-bit field:
633 * 0xx Reserved, NCS backward compatibility
634 * 10x The variant specified in rfc4122
635 * 110 Reserved, Microsoft backward compatibility
636 * 111 Reserved for future definition
639 * For version 4, these bits are set/cleared:
640 * time_hi_and_version & 0x0fff | 0x4000
641 * clk_seq_and_variant & 0x3fff | 0x8000
646 i = open("/dev/urandom", O_RDONLY);
651 /* Paranoia. /dev/urandom may be missing.
652 * rand() is guaranteed to generate at least [0, 2^15) range,
653 * but lowest bits in some libc are not so "random". */
654 srand(monotonic_us()); /* pulls in printf */
657 for (i = 0; i < 16; i++)
658 buf[i] ^= rand() >> 5;
666 buf[4 + 2 ] = (buf[4 + 2 ] & 0x0f) | 0x40;
668 buf[4 + 2 + 2] = (buf[4 + 2 + 2] & 0x3f) | 0x80;
672 pid_t FAST_FUNC xfork(void)
676 if (pid < 0) /* wtf? */
677 bb_perror_msg_and_die("vfork"+1);
682 void FAST_FUNC xvfork_parent_waits_and_exits(void)
690 int exit_status = wait_for_exitstatus(pid);
691 if (WIFSIGNALED(exit_status))
692 kill_myself_with_sig(WTERMSIG(exit_status));
693 _exit(WEXITSTATUS(exit_status));
695 /* Child continues */