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 Denis Vlasenko
9 * Licensed under GPL version 2, see file LICENSE in this tarball for details.
14 /* All the functions starting with "x" call bb_error_msg_and_die() if they
15 * fail, so callers never need to check for errors. If it returned, it
19 /* dmalloc provides variants of these that do abort() on failure.
20 * Since dmalloc's prototypes overwrite the impls here as they are
21 * included after these prototypes in libbb.h, all is well.
23 // Die if we can't allocate size bytes of memory.
24 void *xmalloc(size_t size)
26 void *ptr = malloc(size);
27 if (ptr == NULL && size != 0)
28 bb_error_msg_and_die(bb_msg_memory_exhausted);
32 // Die if we can't resize previously allocated memory. (This returns a pointer
33 // to the new memory, which may or may not be the same as the old memory.
34 // It'll copy the contents to a new chunk and free the old one if necessary.)
35 void *xrealloc(void *ptr, size_t size)
37 ptr = realloc(ptr, size);
38 if (ptr == NULL && size != 0)
39 bb_error_msg_and_die(bb_msg_memory_exhausted);
44 // Die if we can't allocate and zero size bytes of memory.
45 void *xzalloc(size_t size)
47 void *ptr = xmalloc(size);
52 // Die if we can't copy a string to freshly allocated memory.
53 char * xstrdup(const char *s)
63 bb_error_msg_and_die(bb_msg_memory_exhausted);
68 // Die if we can't allocate n+1 bytes (space for the null terminator) and copy
69 // the (possibly truncated to length n) string into it.
70 char * xstrndup(const char *s, int n)
75 if (ENABLE_DEBUG && s == NULL)
76 bb_error_msg_and_die("xstrndup bug");
78 /* We can just xmalloc(n+1) and strncpy into it, */
79 /* but think about xstrndup("abc", 10000) wastage! */
91 return memcpy(t, s, n);
94 // Die if we can't open a file and return a FILE * to it.
95 // Notice we haven't got xfread(), This is for use with fscanf() and friends.
96 FILE *xfopen(const char *path, const char *mode)
98 FILE *fp = fopen(path, mode);
100 bb_perror_msg_and_die("%s", path);
104 // Die if we can't open an existing file and return an fd.
105 int xopen(const char *pathname, int flags)
107 //if (ENABLE_DEBUG && (flags & O_CREAT))
108 // bb_error_msg_and_die("xopen() with O_CREAT");
110 return xopen3(pathname, flags, 0666);
113 // Die if we can't open a new file and return an fd.
114 int xopen3(const char *pathname, int flags, int mode)
118 ret = open(pathname, flags, mode);
120 bb_perror_msg_and_die("%s", pathname);
125 // Turn on nonblocking I/O on a fd
126 int ndelay_on(int fd)
128 return fcntl(fd,F_SETFL,fcntl(fd,F_GETFL,0) | O_NONBLOCK);
131 int ndelay_off(int fd)
133 return fcntl(fd,F_SETFL,fcntl(fd,F_GETFL,0) & ~O_NONBLOCK);
136 // Die with an error message if we can't write the entire buffer.
137 void xwrite(int fd, const void *buf, size_t count)
140 ssize_t size = full_write(fd, buf, count);
142 bb_error_msg_and_die("short write");
146 // Die with an error message if we can't lseek to the right spot.
147 off_t xlseek(int fd, off_t offset, int whence)
149 off_t off = lseek(fd, offset, whence);
150 if (off == (off_t)-1) {
151 if (whence == SEEK_SET)
152 bb_perror_msg_and_die("lseek(%"OFF_FMT"u)", offset);
153 bb_perror_msg_and_die("lseek");
158 // Die with supplied filename if this FILE * has ferror set.
159 void die_if_ferror(FILE *fp, const char *fn)
162 bb_error_msg_and_die("%s: I/O error", fn);
166 // Die with an error message if stdout has ferror set.
167 void die_if_ferror_stdout(void)
169 die_if_ferror(stdout, bb_msg_standard_output);
172 // Die with an error message if we have trouble flushing stdout.
173 void xfflush_stdout(void)
175 if (fflush(stdout)) {
176 bb_perror_msg_and_die(bb_msg_standard_output);
180 // This does a fork/exec in one call, using vfork(). Return PID of new child,
181 // -1 for failure. Runs argv[0], searching path if that has no / in it.
182 pid_t spawn(char **argv)
189 // Be nice to nommu machines.
192 if (pid < 0) return pid;
195 if (ENABLE_FEATURE_EXEC_PREFER_APPLETS && find_applet_by_name(prog))
196 prog = CONFIG_BUSYBOX_EXEC_PATH;
199 // We're sharing a stack with blocked parent, let parent know we failed
200 // and then exit to unblock parent (but don't run atexit() stuff, which
201 // would screw up parent.)
213 // Die with an error message if we can't spawn a child process.
214 pid_t xspawn(char **argv)
216 pid_t pid = spawn(argv);
217 if (pid < 0) bb_perror_msg_and_die("%s", *argv);
221 // Wait for the specified child PID to exit, returning child's error return.
222 int wait4pid(int pid)
226 if (pid == -1 || waitpid(pid, &status, 0) == -1) return -1;
227 if (WIFEXITED(status)) return WEXITSTATUS(status);
228 if (WIFSIGNALED(status)) return WTERMSIG(status);
232 void xsetenv(const char *key, const char *value)
234 if (setenv(key, value, 1))
235 bb_error_msg_and_die(bb_msg_memory_exhausted);
238 // Converts unsigned long long value into compact 4-char
239 // representation. Examples: "1234", "1.2k", " 27M", "123T"
240 // Fifth char is always '\0'
241 void smart_ulltoa5(unsigned long long ul, char buf[5])
247 if (ul > 9999*10) { // do not scale if 9999 or less
248 while (ul >= 10000) {
253 v = ul; // ullong divisions are expensive, avoid them
256 if (!idx) { // 9999 or less: use 1234 format
257 c = buf[0] = " 123456789"[v/10000];
258 if (c!=' ') fmt = "0123456789";
259 c = buf[1] = fmt[v/1000%10];
260 if (c!=' ') fmt = "0123456789";
261 buf[2] = fmt[v/100%10];
262 buf[3] = "0123456789"[v/10%10];
264 if (v>=10*10) { // scaled value is >=10: use 123M format
265 c = buf[0] = " 123456789"[v/1000];
266 if (c!=' ') fmt = "0123456789";
267 buf[1] = fmt[v/100%10];
268 buf[2] = "0123456789"[v/10%10];
269 } else { // scaled value is <10: use 1.2M format
270 buf[0] = "0123456789"[v/10];
272 buf[2] = "0123456789"[v%10];
274 // see http://en.wikipedia.org/wiki/Tera
275 buf[3] = " kMGTPEZY"[idx];
280 // Convert unsigned integer to ascii, writing into supplied buffer. A
281 // truncated result is always null terminated (unless buflen is 0), and
282 // contains the first few digits of the result ala strncpy.
283 void BUG_sizeof_unsigned_not_4(void);
284 void utoa_to_buf(unsigned n, char *buf, unsigned buflen)
286 unsigned i, out, res;
287 if (sizeof(unsigned) != 4)
288 BUG_sizeof_unsigned_not_4();
291 for (i = 1000000000; i; i /= 10) {
293 if (res || out || i == 1) {
294 if (!--buflen) break;
304 // Convert signed integer to ascii, like utoa_to_buf()
305 void itoa_to_buf(int n, char *buf, unsigned buflen)
312 utoa_to_buf((unsigned)n, buf, buflen);
315 // The following two functions use a static buffer, so calling either one a
316 // second time will overwrite previous results.
318 // The largest 32 bit integer is -2 billion plus null terminator, or 12 bytes.
319 // Int should always be 32 bits on any remotely Unix-like system, see
320 // http://www.unix.org/whitepapers/64bit.html for the reasons why.
322 static char local_buf[12];
324 // Convert unsigned integer to ascii using a static buffer (returned).
325 char *utoa(unsigned n)
327 utoa_to_buf(n, local_buf, sizeof(local_buf));
332 // Convert signed integer to ascii using a static buffer (returned).
335 itoa_to_buf(n, local_buf, sizeof(local_buf));
340 // Emit a string of hex representation of bytes
341 char *bin2hex(char *p, const char *cp, int count)
344 unsigned char c = *cp++;
345 /* put lowercase hex digits */
346 *p++ = 0x20 | bb_hexdigits_upcase[c >> 4];
347 *p++ = 0x20 | bb_hexdigits_upcase[c & 0xf];
353 // Die with an error message if we can't set gid. (Because resource limits may
354 // limit this user to a given number of processes, and if that fills up the
355 // setgid() will fail and we'll _still_be_root_, which is bad.)
356 void xsetgid(gid_t gid)
358 if (setgid(gid)) bb_error_msg_and_die("setgid");
361 // Die with an error message if we can't set uid. (See xsetgid() for why.)
362 void xsetuid(uid_t uid)
364 if (setuid(uid)) bb_error_msg_and_die("setuid");
367 // Return how long the file at fd is, if there's any way to determine it.
368 off_t fdlength(int fd)
370 off_t bottom = 0, top = 0, pos;
373 // If the ioctl works for this, return it.
375 if (ioctl(fd, BLKGETSIZE, &size) >= 0) return size*512;
377 // FIXME: explain why lseek(SEEK_END) is not used here!
379 // If not, do a binary search for the last location we can read. (Some
380 // block devices don't do BLKGETSIZE right.)
385 pos = bottom + (top - bottom) / 2;
387 // If we can read from the current location, it's bigger.
389 if (lseek(fd, pos, SEEK_SET)>=0 && safe_read(fd, &temp, 1)==1) {
390 if (bottom == top) bottom = top = (top+1) * 2;
393 // If we can't, it's smaller.
402 } while (bottom + 1 != top);
407 // Die with an error message if we can't malloc() enough space and do an
408 // sprintf() into that space.
409 char *xasprintf(const char *format, ...)
418 r = vasprintf(&string_ptr, format, p);
421 // Bloat for systems that haven't got the GNU extension.
423 r = vsnprintf(NULL, 0, format, p);
425 string_ptr = xmalloc(r+1);
427 r = vsnprintf(string_ptr, r+1, format, p);
431 if (r < 0) bb_error_msg_and_die(bb_msg_memory_exhausted);
435 #if 0 /* If we will ever meet a libc which hasn't [f]dprintf... */
436 int fdprintf(int fd, const char *format, ...)
445 r = vasprintf(&string_ptr, format, p);
448 // Bloat for systems that haven't got the GNU extension.
450 r = vsnprintf(NULL, 0, format, p);
452 string_ptr = xmalloc(r+1);
454 r = vsnprintf(string_ptr, r+1, format, p);
459 full_write(fd, string_ptr, r);
466 // Die with an error message if we can't copy an entire FILE * to stdout, then
468 void xprint_and_close_file(FILE *file)
471 // copyfd outputs error messages for us.
472 if (bb_copyfd_eof(fileno(file), 1) == -1)
473 exit(xfunc_error_retval);
478 // Die if we can't chdir to a new path.
479 void xchdir(const char *path)
482 bb_perror_msg_and_die("chdir(%s)", path);
485 // Print a warning message if opendir() fails, but don't die.
486 DIR *warn_opendir(const char *path)
490 if ((dp = opendir(path)) == NULL) {
491 bb_perror_msg("cannot open '%s'", path);
497 // Die with an error message if opendir() fails.
498 DIR *xopendir(const char *path)
502 if ((dp = opendir(path)) == NULL)
503 bb_perror_msg_and_die("cannot open '%s'", path);
508 // Die with an error message if we can't daemonize.
509 void xdaemon(int nochdir, int noclose)
511 if (daemon(nochdir, noclose))
512 bb_perror_msg_and_die("daemon");
516 void bb_sanitize_stdio_maybe_daemonize(int daemonize)
520 fd = xopen(bb_dev_null, O_RDWR);
522 fd = dup(fd); /* have 0,1,2 open at least to /dev/null */
525 if (pid < 0) /* wtf? */
526 bb_perror_msg_and_die("fork");
527 if (pid) /* parent */
530 /* if daemonizing, make sure we detach from stdio */
537 close(fd--); /* close everything after fd#2 */
539 void bb_sanitize_stdio(void)
541 bb_sanitize_stdio_maybe_daemonize(0);
543 void bb_daemonize(void)
545 bb_sanitize_stdio_maybe_daemonize(1);
548 // Die with an error message if we can't open a new socket.
549 int xsocket(int domain, int type, int protocol)
551 int r = socket(domain, type, protocol);
553 if (r < 0) bb_perror_msg_and_die("socket");
558 // Die with an error message if we can't bind a socket to an address.
559 void xbind(int sockfd, struct sockaddr *my_addr, socklen_t addrlen)
561 if (bind(sockfd, my_addr, addrlen)) bb_perror_msg_and_die("bind");
564 // Die with an error message if we can't listen for connections on a socket.
565 void xlisten(int s, int backlog)
567 if (listen(s, backlog)) bb_perror_msg_and_die("listen");
570 // xstat() - a stat() which dies on failure with meaningful error message
571 void xstat(const char *name, struct stat *stat_buf)
573 if (stat(name, stat_buf))
574 bb_perror_msg_and_die("can't stat '%s'", name);
577 /* It is perfectly ok to pass in a NULL for either width or for
578 * height, in which case that value will not be set. */
579 int get_terminal_width_height(const int fd, int *width, int *height)
581 struct winsize win = { 0, 0, 0, 0 };
582 int ret = ioctl(fd, TIOCGWINSZ, &win);
586 char *s = getenv("LINES");
587 if (s) win.ws_row = atoi(s);
589 if (win.ws_row <= 1 || win.ws_row >= 30000)
591 *height = (int) win.ws_row;
596 char *s = getenv("COLUMNS");
597 if (s) win.ws_col = atoi(s);
599 if (win.ws_col <= 1 || win.ws_col >= 30000)
601 *width = (int) win.ws_col;