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.
12 /* We need to have separate xfuncs.c and xfuncs_printf.c because
13 * with current linkers, even with section garbage collection,
14 * if *.o module references any of XXXprintf functions, you pull in
15 * entire printf machinery. Even if you do not use the function
16 * which uses XXXprintf.
18 * xfuncs.c contains functions (not necessarily xfuncs)
19 * which do not pull in printf, directly or indirectly.
20 * xfunc_printf.c contains those which do.
26 /* All the functions starting with "x" call bb_error_msg_and_die() if they
27 * fail, so callers never need to check for errors. If it returned, it
31 /* dmalloc provides variants of these that do abort() on failure.
32 * Since dmalloc's prototypes overwrite the impls here as they are
33 * included after these prototypes in libbb.h, all is well.
35 // Warn if we can't allocate size bytes of memory.
36 void* FAST_FUNC malloc_or_warn(size_t size)
38 void *ptr = malloc(size);
39 if (ptr == NULL && size != 0)
40 bb_error_msg(bb_msg_memory_exhausted);
44 // Die if we can't allocate size bytes of memory.
45 void* FAST_FUNC xmalloc(size_t size)
47 void *ptr = malloc(size);
48 if (ptr == NULL && size != 0)
49 bb_error_msg_and_die(bb_msg_memory_exhausted);
53 // Die if we can't resize previously allocated memory. (This returns a pointer
54 // to the new memory, which may or may not be the same as the old memory.
55 // It'll copy the contents to a new chunk and free the old one if necessary.)
56 void* FAST_FUNC xrealloc(void *ptr, size_t size)
58 ptr = realloc(ptr, size);
59 if (ptr == NULL && size != 0)
60 bb_error_msg_and_die(bb_msg_memory_exhausted);
65 // Die if we can't allocate and zero size bytes of memory.
66 void* FAST_FUNC xzalloc(size_t size)
68 void *ptr = xmalloc(size);
73 // Die if we can't copy a string to freshly allocated memory.
74 char* FAST_FUNC xstrdup(const char *s)
84 bb_error_msg_and_die(bb_msg_memory_exhausted);
89 // Die if we can't allocate n+1 bytes (space for the null terminator) and copy
90 // the (possibly truncated to length n) string into it.
91 char* FAST_FUNC xstrndup(const char *s, int n)
96 if (ENABLE_DEBUG && s == NULL)
97 bb_error_msg_and_die("xstrndup bug");
99 /* We can just xmalloc(n+1) and strncpy into it, */
100 /* but think about xstrndup("abc", 10000) wastage! */
112 return memcpy(t, s, n);
115 void* FAST_FUNC xmemdup(const void *s, int n)
117 return memcpy(xmalloc(n), s, n);
120 // Die if we can't open a file and return a FILE* to it.
121 // Notice we haven't got xfread(), This is for use with fscanf() and friends.
122 FILE* FAST_FUNC xfopen(const char *path, const char *mode)
124 FILE *fp = fopen(path, mode);
126 bb_perror_msg_and_die("can't open '%s'", path);
130 // Die if we can't open a file and return a fd.
131 int FAST_FUNC xopen3(const char *pathname, int flags, int mode)
135 ret = open(pathname, flags, mode);
137 bb_perror_msg_and_die("can't open '%s'", pathname);
142 // Die if we can't open a file and return a fd.
143 int FAST_FUNC xopen(const char *pathname, int flags)
145 return xopen3(pathname, flags, 0666);
148 // Warn if we can't open a file and return a fd.
149 int FAST_FUNC open3_or_warn(const char *pathname, int flags, int mode)
153 ret = open(pathname, flags, mode);
155 bb_perror_msg("can't open '%s'", pathname);
160 // Warn if we can't open a file and return a fd.
161 int FAST_FUNC open_or_warn(const char *pathname, int flags)
163 return open3_or_warn(pathname, flags, 0666);
166 /* Die if we can't open an existing file readonly with O_NONBLOCK
168 * Note that for ioctl O_RDONLY is sufficient.
170 int FAST_FUNC xopen_nonblocking(const char *pathname)
172 return xopen(pathname, O_RDONLY | O_NONBLOCK);
175 int FAST_FUNC xopen_as_uid_gid(const char *pathname, int flags, uid_t u, gid_t g)
178 uid_t old_euid = geteuid();
179 gid_t old_egid = getegid();
184 fd = xopen(pathname, flags);
192 void FAST_FUNC xunlink(const char *pathname)
194 if (unlink(pathname))
195 bb_perror_msg_and_die("can't remove file '%s'", pathname);
198 void FAST_FUNC xrename(const char *oldpath, const char *newpath)
200 if (rename(oldpath, newpath))
201 bb_perror_msg_and_die("can't move '%s' to '%s'", oldpath, newpath);
204 int FAST_FUNC rename_or_warn(const char *oldpath, const char *newpath)
206 int n = rename(oldpath, newpath);
208 bb_perror_msg("can't move '%s' to '%s'", oldpath, newpath);
212 void FAST_FUNC xpipe(int filedes[2])
215 bb_perror_msg_and_die("can't create pipe");
218 void FAST_FUNC xdup2(int from, int to)
220 if (dup2(from, to) != to)
221 bb_perror_msg_and_die("can't duplicate file descriptor");
224 // "Renumber" opened fd
225 void FAST_FUNC xmove_fd(int from, int to)
233 // Die with an error message if we can't write the entire buffer.
234 void FAST_FUNC xwrite(int fd, const void *buf, size_t count)
237 ssize_t size = full_write(fd, buf, count);
238 if ((size_t)size != count) {
240 * Two cases: write error immediately;
241 * or some writes succeeded, then we hit an error.
242 * In either case, errno is set.
244 bb_perror_msg_and_die(
245 size >= 0 ? "short write" : "write error"
250 void FAST_FUNC xwrite_str(int fd, const char *str)
252 xwrite(fd, str, strlen(str));
255 void FAST_FUNC xclose(int fd)
258 bb_perror_msg_and_die("close failed");
261 // Die with an error message if we can't lseek to the right spot.
262 off_t FAST_FUNC xlseek(int fd, off_t offset, int whence)
264 off_t off = lseek(fd, offset, whence);
265 if (off == (off_t)-1) {
266 if (whence == SEEK_SET)
267 bb_perror_msg_and_die("lseek(%"OFF_FMT"u)", offset);
268 bb_perror_msg_and_die("lseek");
273 int FAST_FUNC xmkstemp(char *template)
275 int fd = mkstemp(template);
277 bb_perror_msg_and_die("can't create temp file '%s'", template);
281 // Die with supplied filename if this FILE* has ferror set.
282 void FAST_FUNC die_if_ferror(FILE *fp, const char *fn)
285 /* ferror doesn't set useful errno */
286 bb_error_msg_and_die("%s: I/O error", fn);
290 // Die with an error message if stdout has ferror set.
291 void FAST_FUNC die_if_ferror_stdout(void)
293 die_if_ferror(stdout, bb_msg_standard_output);
296 int FAST_FUNC fflush_all(void)
302 int FAST_FUNC bb_putchar(int ch)
307 /* Die with an error message if we can't copy an entire FILE* to stdout,
308 * then close that file. */
309 void FAST_FUNC xprint_and_close_file(FILE *file)
312 // copyfd outputs error messages for us.
313 if (bb_copyfd_eof(fileno(file), STDOUT_FILENO) == -1)
319 // Die with an error message if we can't malloc() enough space and do an
320 // sprintf() into that space.
321 char* FAST_FUNC xasprintf(const char *format, ...)
328 r = vasprintf(&string_ptr, format, p);
332 bb_error_msg_and_die(bb_msg_memory_exhausted);
336 void FAST_FUNC xsetenv(const char *key, const char *value)
338 if (setenv(key, value, 1))
339 bb_error_msg_and_die(bb_msg_memory_exhausted);
342 /* Handles "VAR=VAL" strings, even those which are part of environ
345 void FAST_FUNC bb_unsetenv(const char *var)
347 char onstack[128 - 16]; /* smaller stack setup code on x86 */
350 tp = strchr(var, '=');
352 /* In case var was putenv'ed, we can't replace '='
353 * with NUL and unsetenv(var) - it won't work,
354 * env is modified by the replacement, unsetenv
355 * sees "VAR" instead of "VAR=VAL" and does not remove it!
358 unsigned sz = tp - var;
359 if (sz < sizeof(onstack)) {
360 ((char*)mempcpy(onstack, var, sz))[0] = '\0';
364 /* unlikely: very long var name */
365 var = tp = xstrndup(var, sz);
372 void FAST_FUNC bb_unsetenv_and_free(char *var)
378 // Die with an error message if we can't set gid. (Because resource limits may
379 // limit this user to a given number of processes, and if that fills up the
380 // setgid() will fail and we'll _still_be_root_, which is bad.)
381 void FAST_FUNC xsetgid(gid_t gid)
383 if (setgid(gid)) bb_perror_msg_and_die("setgid");
386 // Die with an error message if we can't set uid. (See xsetgid() for why.)
387 void FAST_FUNC xsetuid(uid_t uid)
389 if (setuid(uid)) bb_perror_msg_and_die("setuid");
392 void FAST_FUNC xsetegid(gid_t egid)
394 if (setegid(egid)) bb_perror_msg_and_die("setegid");
397 void FAST_FUNC xseteuid(uid_t euid)
399 if (seteuid(euid)) bb_perror_msg_and_die("seteuid");
402 // Die if we can't chdir to a new path.
403 void FAST_FUNC xchdir(const char *path)
406 bb_perror_msg_and_die("can't change directory to '%s'", path);
409 void FAST_FUNC xfchdir(int fd)
412 bb_perror_msg_and_die("fchdir");
415 void FAST_FUNC xchroot(const char *path)
418 bb_perror_msg_and_die("can't change root directory to '%s'", path);
422 // Print a warning message if opendir() fails, but don't die.
423 DIR* FAST_FUNC warn_opendir(const char *path)
429 bb_perror_msg("can't open '%s'", path);
433 // Die with an error message if opendir() fails.
434 DIR* FAST_FUNC xopendir(const char *path)
440 bb_perror_msg_and_die("can't open '%s'", path);
444 // Die with an error message if we can't open a new socket.
445 int FAST_FUNC xsocket(int domain, int type, int protocol)
447 int r = socket(domain, type, protocol);
450 /* Hijack vaguely related config option */
451 #if ENABLE_VERBOSE_RESOLUTION_ERRORS
452 const char *s = "INET";
454 if (domain == AF_PACKET) s = "PACKET";
457 if (domain == AF_NETLINK) s = "NETLINK";
459 IF_FEATURE_IPV6(if (domain == AF_INET6) s = "INET6";)
460 bb_perror_msg_and_die("socket(AF_%s,%d,%d)", s, type, protocol);
462 bb_perror_msg_and_die("socket");
469 // Die with an error message if we can't bind a socket to an address.
470 void FAST_FUNC xbind(int sockfd, struct sockaddr *my_addr, socklen_t addrlen)
472 if (bind(sockfd, my_addr, addrlen)) bb_perror_msg_and_die("bind");
475 // Die with an error message if we can't listen for connections on a socket.
476 void FAST_FUNC xlisten(int s, int backlog)
478 if (listen(s, backlog)) bb_perror_msg_and_die("listen");
481 /* Die with an error message if sendto failed.
482 * Return bytes sent otherwise */
483 ssize_t FAST_FUNC xsendto(int s, const void *buf, size_t len, const struct sockaddr *to,
486 ssize_t ret = sendto(s, buf, len, 0, to, tolen);
488 if (ENABLE_FEATURE_CLEAN_UP)
490 bb_perror_msg_and_die("sendto");
495 // xstat() - a stat() which dies on failure with meaningful error message
496 void FAST_FUNC xstat(const char *name, struct stat *stat_buf)
498 if (stat(name, stat_buf))
499 bb_perror_msg_and_die("can't stat '%s'", name);
502 void FAST_FUNC xfstat(int fd, struct stat *stat_buf, const char *errmsg)
504 /* errmsg is usually a file name, but not always:
505 * xfstat may be called in a spot where file name is no longer
506 * available, and caller may give e.g. "can't stat input file" string.
508 if (fstat(fd, stat_buf))
509 bb_simple_perror_msg_and_die(errmsg);
512 // selinux_or_die() - die if SELinux is disabled.
513 void FAST_FUNC selinux_or_die(void)
516 int rc = is_selinux_enabled();
518 bb_error_msg_and_die("SELinux is disabled");
520 bb_error_msg_and_die("is_selinux_enabled() failed");
523 bb_error_msg_and_die("SELinux support is disabled");
527 int FAST_FUNC ioctl_or_perror_and_die(int fd, unsigned request, void *argp, const char *fmt,...)
532 ret = ioctl(fd, request, argp);
535 bb_verror_msg(fmt, p, strerror(errno));
536 /* xfunc_die can actually longjmp, so be nice */
543 int FAST_FUNC ioctl_or_perror(int fd, unsigned request, void *argp, const char *fmt,...)
546 int ret = ioctl(fd, request, argp);
550 bb_verror_msg(fmt, p, strerror(errno));
556 #if ENABLE_IOCTL_HEX2STR_ERROR
557 int FAST_FUNC bb_ioctl_or_warn(int fd, unsigned request, void *argp, const char *ioctl_name)
561 ret = ioctl(fd, request, argp);
563 bb_simple_perror_msg(ioctl_name);
566 int FAST_FUNC bb_xioctl(int fd, unsigned request, void *argp, const char *ioctl_name)
570 ret = ioctl(fd, request, argp);
572 bb_simple_perror_msg_and_die(ioctl_name);
576 int FAST_FUNC bb_ioctl_or_warn(int fd, unsigned request, void *argp)
580 ret = ioctl(fd, request, argp);
582 bb_perror_msg("ioctl %#x failed", request);
585 int FAST_FUNC bb_xioctl(int fd, unsigned request, void *argp)
589 ret = ioctl(fd, request, argp);
591 bb_perror_msg_and_die("ioctl %#x failed", request);
596 char* FAST_FUNC xmalloc_ttyname(int fd)
599 int r = ttyname_r(fd, buf, sizeof(buf) - 1);
605 void FAST_FUNC generate_uuid(uint8_t *buf)
607 /* http://www.ietf.org/rfc/rfc4122.txt
608 * 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
609 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
611 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
612 * | time_mid | time_hi_and_version |
613 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
614 * |clk_seq_and_variant | node (0-1) |
615 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
617 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
618 * IOW, uuid has this layout:
619 * uint32_t time_low (big endian)
620 * uint16_t time_mid (big endian)
621 * uint16_t time_hi_and_version (big endian)
622 * version is a 4-bit field:
624 * 2 DCE Security, with embedded POSIX UIDs
626 * 4 Randomly generated
627 * 5 Name-based (SHA-1)
628 * uint16_t clk_seq_and_variant (big endian)
629 * variant is a 3-bit field:
630 * 0xx Reserved, NCS backward compatibility
631 * 10x The variant specified in rfc4122
632 * 110 Reserved, Microsoft backward compatibility
633 * 111 Reserved for future definition
636 * For version 4, these bits are set/cleared:
637 * time_hi_and_version & 0x0fff | 0x4000
638 * clk_seq_and_variant & 0x3fff | 0x8000
643 i = open("/dev/urandom", O_RDONLY);
648 /* Paranoia. /dev/urandom may be missing.
649 * rand() is guaranteed to generate at least [0, 2^15) range,
650 * but lowest bits in some libc are not so "random". */
651 srand(monotonic_us()); /* pulls in printf */
654 for (i = 0; i < 16; i++)
655 buf[i] ^= rand() >> 5;
663 buf[4 + 2 ] = (buf[4 + 2 ] & 0x0f) | 0x40;
665 buf[4 + 2 + 2] = (buf[4 + 2 + 2] & 0x3f) | 0x80;
669 pid_t FAST_FUNC xfork(void)
673 if (pid < 0) /* wtf? */
674 bb_perror_msg_and_die("vfork"+1);
679 void FAST_FUNC xvfork_parent_waits_and_exits(void)
687 int exit_status = wait_for_exitstatus(pid);
688 if (WIFSIGNALED(exit_status))
689 kill_myself_with_sig(WTERMSIG(exit_status));
690 _exit(WEXITSTATUS(exit_status));
692 /* Child continues */