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! */
93 // Die if we can't open a file and return a FILE * to it.
94 // Notice we haven't got xfread(), This is for use with fscanf() and friends.
95 FILE *xfopen(const char *path, const char *mode)
97 FILE *fp = fopen(path, mode);
99 bb_perror_msg_and_die("%s", path);
103 // Die if we can't open an existing file and return an fd.
104 int xopen(const char *pathname, int flags)
106 //if (ENABLE_DEBUG && (flags & O_CREAT))
107 // bb_error_msg_and_die("xopen() with O_CREAT");
109 return xopen3(pathname, flags, 0666);
112 // Die if we can't open a new file and return an fd.
113 int xopen3(const char *pathname, int flags, int mode)
117 ret = open(pathname, flags, mode);
119 bb_perror_msg_and_die("%s", pathname);
124 // Turn on nonblocking I/O on a fd
125 int ndelay_on(int fd)
127 return fcntl(fd,F_SETFL,fcntl(fd,F_GETFL,0) | O_NONBLOCK);
130 int ndelay_off(int fd)
132 return fcntl(fd,F_SETFL,fcntl(fd,F_GETFL,0) & ~O_NONBLOCK);
135 // Die with an error message if we can't write the entire buffer.
136 void xwrite(int fd, const void *buf, size_t count)
139 ssize_t size = full_write(fd, buf, count);
141 bb_error_msg_and_die("short write");
145 // Die with an error message if we can't lseek to the right spot.
146 off_t xlseek(int fd, off_t offset, int whence)
148 off_t off = lseek(fd, offset, whence);
149 if (off == (off_t)-1) {
150 if (whence == SEEK_SET)
151 bb_perror_msg_and_die("lseek(%"OFF_FMT"u)", offset);
152 bb_perror_msg_and_die("lseek");
157 // Die with supplied filename if this FILE * has ferror set.
158 void die_if_ferror(FILE *fp, const char *fn)
161 bb_error_msg_and_die("%s: I/O error", fn);
165 // Die with an error message if stdout has ferror set.
166 void die_if_ferror_stdout(void)
168 die_if_ferror(stdout, bb_msg_standard_output);
171 // Die with an error message if we have trouble flushing stdout.
172 void xfflush_stdout(void)
174 if (fflush(stdout)) {
175 bb_perror_msg_and_die(bb_msg_standard_output);
179 // This does a fork/exec in one call, using vfork(). Return PID of new child,
180 // -1 for failure. Runs argv[0], searching path if that has no / in it.
181 pid_t spawn(char **argv)
186 void *app = ENABLE_FEATURE_SH_STANDALONE_SHELL ? find_applet_by_name(argv[0]) : 0;
188 // Be nice to nommu machines.
191 if (pid < 0) return pid;
193 execvp(app ? CONFIG_BUSYBOX_EXEC_PATH : *argv, argv);
195 // We're sharing a stack with blocked parent, let parent know we failed
196 // and then exit to unblock parent (but don't run atexit() stuff, which
197 // would screw up parent.)
209 // Die with an error message if we can't spawn a child process.
210 pid_t xspawn(char **argv)
212 pid_t pid = spawn(argv);
213 if (pid < 0) bb_perror_msg_and_die("%s", *argv);
217 // Wait for the specified child PID to exit, returning child's error return.
218 int wait4pid(int pid)
222 if (pid == -1 || waitpid(pid, &status, 0) == -1) return -1;
223 if (WIFEXITED(status)) return WEXITSTATUS(status);
224 if (WIFSIGNALED(status)) return WTERMSIG(status);
228 void xsetenv(const char *key, const char *value)
230 if (setenv(key, value, 1))
231 bb_error_msg_and_die(bb_msg_memory_exhausted);
234 // Converts unsigned long long value into compact 4-char
235 // representation. Examples: "1234", "1.2k", " 27M", "123T"
236 // Fifth char is always '\0'
237 void smart_ulltoa5(unsigned long long ul, char buf[5])
243 if (ul > 9999*10) { // do not scale if 9999 or less
244 while (ul >= 10000) {
249 v = ul; // ullong divisions are expensive, avoid them
252 if (!idx) { // 9999 or less: use 1234 format
253 c = buf[0] = " 123456789"[v/10000];
254 if (c!=' ') fmt = "0123456789";
255 c = buf[1] = fmt[v/1000%10];
256 if (c!=' ') fmt = "0123456789";
257 buf[2] = fmt[v/100%10];
258 buf[3] = "0123456789"[v/10%10];
260 if (v>=10*10) { // scaled value is >=10: use 123M format
261 c = buf[0] = " 123456789"[v/1000];
262 if (c!=' ') fmt = "0123456789";
263 buf[1] = fmt[v/100%10];
264 buf[2] = "0123456789"[v/10%10];
265 } else { // scaled value is <10: use 1.2M format
266 buf[0] = "0123456789"[v/10];
268 buf[2] = "0123456789"[v%10];
270 // see http://en.wikipedia.org/wiki/Tera
271 buf[3] = " kMGTPEZY"[idx];
276 // Convert unsigned integer to ascii, writing into supplied buffer. A
277 // truncated result is always null terminated (unless buflen is 0), and
278 // contains the first few digits of the result ala strncpy.
279 void BUG_sizeof_unsigned_not_4(void);
280 void utoa_to_buf(unsigned n, char *buf, unsigned buflen)
282 unsigned i, out, res;
283 if (sizeof(unsigned) != 4)
284 BUG_sizeof_unsigned_not_4();
287 for (i = 1000000000; i; i /= 10) {
289 if (res || out || i == 1) {
290 if (!--buflen) break;
300 // Convert signed integer to ascii, like utoa_to_buf()
301 void itoa_to_buf(int n, char *buf, unsigned buflen)
308 utoa_to_buf((unsigned)n, buf, buflen);
311 // The following two functions use a static buffer, so calling either one a
312 // second time will overwrite previous results.
314 // The largest 32 bit integer is -2 billion plus null terminator, or 12 bytes.
315 // Int should always be 32 bits on any remotely Unix-like system, see
316 // http://www.unix.org/whitepapers/64bit.html for the reasons why.
318 static char local_buf[12];
320 // Convert unsigned integer to ascii using a static buffer (returned).
321 char *utoa(unsigned n)
323 utoa_to_buf(n, local_buf, sizeof(local_buf));
328 // Convert signed integer to ascii using a static buffer (returned).
331 itoa_to_buf(n, local_buf, sizeof(local_buf));
336 // Emit a string of hex representation of bytes
337 char *bin2hex(char *p, const char *cp, int count)
340 unsigned char c = *cp++;
341 /* put lowercase hex digits */
342 *p++ = 0x10 | bb_hexdigits_upcase[c >> 4];
343 *p++ = 0x10 | bb_hexdigits_upcase[c & 0xf];
349 // Die with an error message if we can't set gid. (Because resource limits may
350 // limit this user to a given number of processes, and if that fills up the
351 // setgid() will fail and we'll _still_be_root_, which is bad.)
352 void xsetgid(gid_t gid)
354 if (setgid(gid)) bb_error_msg_and_die("setgid");
357 // Die with an error message if we can't set uid. (See xsetgid() for why.)
358 void xsetuid(uid_t uid)
360 if (setuid(uid)) bb_error_msg_and_die("setuid");
363 // Return how long the file at fd is, if there's any way to determine it.
364 off_t fdlength(int fd)
366 off_t bottom = 0, top = 0, pos;
369 // If the ioctl works for this, return it.
371 if (ioctl(fd, BLKGETSIZE, &size) >= 0) return size*512;
373 // FIXME: explain why lseek(SEEK_END) is not used here!
375 // If not, do a binary search for the last location we can read. (Some
376 // block devices don't do BLKGETSIZE right.)
381 pos = bottom + (top - bottom) / 2;
383 // If we can read from the current location, it's bigger.
385 if (lseek(fd, pos, SEEK_SET)>=0 && safe_read(fd, &temp, 1)==1) {
386 if (bottom == top) bottom = top = (top+1) * 2;
389 // If we can't, it's smaller.
398 } while (bottom + 1 != top);
403 // Die with an error message if we can't malloc() enough space and do an
404 // sprintf() into that space.
405 char *xasprintf(const char *format, ...)
414 r = vasprintf(&string_ptr, format, p);
417 // Bloat for systems that haven't got the GNU extension.
419 r = vsnprintf(NULL, 0, format, p);
421 string_ptr = xmalloc(r+1);
423 r = vsnprintf(string_ptr, r+1, format, p);
427 if (r < 0) bb_error_msg_and_die(bb_msg_memory_exhausted);
431 #if 0 /* If we will ever meet a libc which hasn't [f]dprintf... */
432 int fdprintf(int fd, const char *format, ...)
441 r = vasprintf(&string_ptr, format, p);
444 // Bloat for systems that haven't got the GNU extension.
446 r = vsnprintf(NULL, 0, format, p);
448 string_ptr = xmalloc(r+1);
450 r = vsnprintf(string_ptr, r+1, format, p);
455 full_write(fd, string_ptr, r);
462 // Die with an error message if we can't copy an entire FILE * to stdout, then
464 void xprint_and_close_file(FILE *file)
467 // copyfd outputs error messages for us.
468 if (bb_copyfd_eof(fileno(file), 1) == -1)
469 exit(xfunc_error_retval);
474 // Die if we can't chdir to a new path.
475 void xchdir(const char *path)
478 bb_perror_msg_and_die("chdir(%s)", path);
481 // Print a warning message if opendir() fails, but don't die.
482 DIR *warn_opendir(const char *path)
486 if ((dp = opendir(path)) == NULL) {
487 bb_perror_msg("cannot open '%s'", path);
493 // Die with an error message if opendir() fails.
494 DIR *xopendir(const char *path)
498 if ((dp = opendir(path)) == NULL)
499 bb_perror_msg_and_die("cannot open '%s'", path);
504 // Die with an error message if we can't daemonize.
505 void xdaemon(int nochdir, int noclose)
507 if (daemon(nochdir, noclose))
508 bb_perror_msg_and_die("daemon");
512 void bb_sanitize_stdio_maybe_daemonize(int daemonize)
516 fd = xopen(bb_dev_null, O_RDWR);
518 fd = dup(fd); /* have 0,1,2 open at least to /dev/null */
521 if (pid < 0) /* wtf? */
522 bb_perror_msg_and_die("fork");
523 if (pid) /* parent */
526 /* if daemonizing, make sure we detach from stdio */
533 close(fd--); /* close everything after fd#2 */
535 void bb_sanitize_stdio(void)
537 bb_sanitize_stdio_maybe_daemonize(0);
539 void bb_daemonize(void)
541 bb_sanitize_stdio_maybe_daemonize(1);
544 // Die with an error message if we can't open a new socket.
545 int xsocket(int domain, int type, int protocol)
547 int r = socket(domain, type, protocol);
549 if (r < 0) bb_perror_msg_and_die("socket");
554 // Die with an error message if we can't bind a socket to an address.
555 void xbind(int sockfd, struct sockaddr *my_addr, socklen_t addrlen)
557 if (bind(sockfd, my_addr, addrlen)) bb_perror_msg_and_die("bind");
560 // Die with an error message if we can't listen for connections on a socket.
561 void xlisten(int s, int backlog)
563 if (listen(s, backlog)) bb_perror_msg_and_die("listen");
566 // xstat() - a stat() which dies on failure with meaningful error message
567 void xstat(char *name, struct stat *stat_buf)
569 if (stat(name, stat_buf))
570 bb_perror_msg_and_die("can't stat '%s'", name);
573 /* It is perfectly ok to pass in a NULL for either width or for
574 * height, in which case that value will not be set. */
575 int get_terminal_width_height(int fd, int *width, int *height)
577 struct winsize win = { 0, 0, 0, 0 };
578 int ret = ioctl(fd, TIOCGWINSZ, &win);
582 char *s = getenv("LINES");
583 if (s) win.ws_row = atoi(s);
585 if (win.ws_row <= 1 || win.ws_row >= 30000)
587 *height = (int) win.ws_row;
592 char *s = getenv("COLUMNS");
593 if (s) win.ws_col = atoi(s);
595 if (win.ws_col <= 1 || win.ws_col >= 30000)
597 *width = (int) win.ws_col;