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);
125 int ndelay_off(int fd)
127 return fcntl(fd,F_SETFL,fcntl(fd,F_GETFL,0) & ~O_NONBLOCK);
130 // Turn on nonblocking I/O on a fd
131 int ndelay_on(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 bb_perror_msg_and_die("lseek");
155 // Die with supplied filename if this FILE * has ferror set.
156 void die_if_ferror(FILE *fp, const char *fn)
159 bb_error_msg_and_die("%s: I/O error", fn);
163 // Die with an error message if stdout has ferror set.
164 void die_if_ferror_stdout(void)
166 die_if_ferror(stdout, bb_msg_standard_output);
169 // Die with an error message if we have trouble flushing stdout.
170 void xfflush_stdout(void)
172 if (fflush(stdout)) {
173 bb_perror_msg_and_die(bb_msg_standard_output);
177 // This does a fork/exec in one call, using vfork(). Return PID of new child,
178 // -1 for failure. Runs argv[0], searching path if that has no / in it.
179 pid_t spawn(char **argv)
183 void *app = ENABLE_FEATURE_SH_STANDALONE_SHELL ? find_applet_by_name(argv[0]) : 0;
185 // Be nice to nommu machines.
188 if (pid < 0) return pid;
190 execvp(app ? CONFIG_BUSYBOX_EXEC_PATH : *argv, argv);
192 // We're sharing a stack with blocked parent, let parent know we failed
193 // and then exit to unblock parent (but don't run atexit() stuff, which
194 // would screw up parent.)
199 return failed ? failed : pid;
202 // Die with an error message if we can't spawn a child process.
203 pid_t xspawn(char **argv)
205 pid_t pid = spawn(argv);
206 if (pid < 0) bb_perror_msg_and_die("%s", *argv);
210 // Wait for the specified child PID to exit, returning child's error return.
211 int wait4pid(int pid)
215 if (pid == -1 || waitpid(pid, &status, 0) == -1) return -1;
216 if (WIFEXITED(status)) return WEXITSTATUS(status);
217 if (WIFSIGNALED(status)) return WTERMSIG(status);
221 void xsetenv(const char *key, const char *value)
223 if (setenv(key, value, 1))
224 bb_error_msg_and_die(bb_msg_memory_exhausted);
227 // Converts unsigned long long value into compact 4-char
228 // representation. Examples: "1234", "1.2k", " 27M", "123T"
229 // Fifth char is always '\0'
230 void smart_ulltoa5(unsigned long long ul, char buf[5])
236 if (ul > 9999*10) { // do not scale if 9999 or less
237 while (ul >= 10000) {
242 v = ul; // ullong divisions are expensive, avoid them
245 if (!idx) { // 9999 or less: use 1234 format
246 c = buf[0] = " 123456789"[v/10000];
247 if (c!=' ') fmt = "0123456789";
248 c = buf[1] = fmt[v/1000%10];
249 if (c!=' ') fmt = "0123456789";
250 buf[2] = fmt[v/100%10];
251 buf[3] = "0123456789"[v/10%10];
253 if (v>=10*10) { // scaled value is >=10: use 123M format
254 c = buf[0] = " 123456789"[v/1000];
255 if (c!=' ') fmt = "0123456789";
256 buf[1] = fmt[v/100%10];
257 buf[2] = "0123456789"[v/10%10];
258 } else { // scaled value is <10: use 1.2M format
259 buf[0] = "0123456789"[v/10];
261 buf[2] = "0123456789"[v%10];
263 // see http://en.wikipedia.org/wiki/Tera
264 buf[3] = " kMGTPEZY"[idx];
269 // Convert unsigned integer to ascii, writing into supplied buffer. A
270 // truncated result is always null terminated (unless buflen is 0), and
271 // contains the first few digits of the result ala strncpy.
272 void BUG_sizeof_unsigned_not_4(void);
273 void utoa_to_buf(unsigned n, char *buf, unsigned buflen)
275 unsigned i, out, res;
276 if (sizeof(unsigned) != 4)
277 BUG_sizeof_unsigned_not_4();
280 for (i = 1000000000; i; i /= 10) {
282 if (res || out || i == 1) {
283 if (!--buflen) break;
293 // Convert signed integer to ascii, like utoa_to_buf()
294 void itoa_to_buf(int n, char *buf, unsigned buflen)
301 utoa_to_buf((unsigned)n, buf, buflen);
304 // The following two functions use a static buffer, so calling either one a
305 // second time will overwrite previous results.
307 // The largest 32 bit integer is -2 billion plus null terminator, or 12 bytes.
308 // Int should always be 32 bits on any remotely Unix-like system, see
309 // http://www.unix.org/whitepapers/64bit.html for the reasons why.
311 static char local_buf[12];
313 // Convert unsigned integer to ascii using a static buffer (returned).
314 char *utoa(unsigned n)
316 utoa_to_buf(n, local_buf, sizeof(local_buf));
321 // Convert signed integer to ascii using a static buffer (returned).
324 itoa_to_buf(n, local_buf, sizeof(local_buf));
329 // Die with an error message if we can't set gid. (Because resource limits may
330 // limit this user to a given number of processes, and if that fills up the
331 // setgid() will fail and we'll _still_be_root_, which is bad.)
332 void xsetgid(gid_t gid)
334 if (setgid(gid)) bb_error_msg_and_die("setgid");
337 // Die with an error message if we can't set uid. (See xsetgid() for why.)
338 void xsetuid(uid_t uid)
340 if (setuid(uid)) bb_error_msg_and_die("setuid");
343 // Return how long the file at fd is, if there's any way to determine it.
344 off_t fdlength(int fd)
346 off_t bottom = 0, top = 0, pos;
349 // If the ioctl works for this, return it.
351 if (ioctl(fd, BLKGETSIZE, &size) >= 0) return size*512;
353 // FIXME: explain why lseek(SEEK_END) is not used here!
355 // If not, do a binary search for the last location we can read. (Some
356 // block devices don't do BLKGETSIZE right.)
361 pos = bottom + (top - bottom) / 2;
363 // If we can read from the current location, it's bigger.
365 if (lseek(fd, pos, SEEK_SET)>=0 && safe_read(fd, &temp, 1)==1) {
366 if (bottom == top) bottom = top = (top+1) * 2;
369 // If we can't, it's smaller.
378 } while (bottom + 1 != top);
383 // Die with an error message if we can't malloc() enough space and do an
384 // sprintf() into that space.
385 char *xasprintf(const char *format, ...)
394 r = vasprintf(&string_ptr, format, p);
397 // Bloat for systems that haven't got the GNU extension.
399 r = vsnprintf(NULL, 0, format, p);
401 string_ptr = xmalloc(r+1);
403 r = vsnprintf(string_ptr, r+1, format, p);
407 if (r < 0) bb_error_msg_and_die(bb_msg_memory_exhausted);
411 // Die with an error message if we can't copy an entire FILE * to stdout, then
413 void xprint_and_close_file(FILE *file)
416 // copyfd outputs error messages for us.
417 if (bb_copyfd_eof(fileno(file), 1) == -1)
418 exit(xfunc_error_retval);
423 // Die if we can't chdir to a new path.
424 void xchdir(const char *path)
427 bb_perror_msg_and_die("chdir(%s)", path);
430 // Print a warning message if opendir() fails, but don't die.
431 DIR *warn_opendir(const char *path)
435 if ((dp = opendir(path)) == NULL) {
436 bb_perror_msg("cannot open '%s'", path);
442 // Die with an error message if opendir() fails.
443 DIR *xopendir(const char *path)
447 if ((dp = opendir(path)) == NULL)
448 bb_perror_msg_and_die("cannot open '%s'", path);
453 // Die with an error message if we can't daemonize.
454 void xdaemon(int nochdir, int noclose)
456 if (daemon(nochdir, noclose))
457 bb_perror_msg_and_die("daemon");
461 // Die with an error message if we can't open a new socket.
462 int xsocket(int domain, int type, int protocol)
464 int r = socket(domain, type, protocol);
466 if (r < 0) bb_perror_msg_and_die("socket");
471 // Die with an error message if we can't bind a socket to an address.
472 void xbind(int sockfd, struct sockaddr *my_addr, socklen_t addrlen)
474 if (bind(sockfd, my_addr, addrlen)) bb_perror_msg_and_die("bind");
477 // Die with an error message if we can't listen for connections on a socket.
478 void xlisten(int s, int backlog)
480 if (listen(s, backlog)) bb_perror_msg_and_die("listen");
483 // xstat() - a stat() which dies on failure with meaningful error message
484 void xstat(char *name, struct stat *stat_buf)
486 if (stat(name, stat_buf))
487 bb_perror_msg_and_die("can't stat '%s'", name);
490 /* It is perfectly ok to pass in a NULL for either width or for
491 * height, in which case that value will not be set. */
492 int get_terminal_width_height(int fd, int *width, int *height)
494 struct winsize win = { 0, 0, 0, 0 };
495 int ret = ioctl(fd, TIOCGWINSZ, &win);
499 char *s = getenv("LINES");
500 if (s) win.ws_row = atoi(s);
502 if (win.ws_row <= 1 || win.ws_row >= 30000)
504 *height = (int) win.ws_row;
509 char *s = getenv("COLUMNS");
510 if (s) win.ws_col = atoi(s);
512 if (win.ws_col <= 1 || win.ws_col >= 30000)
514 *width = (int) win.ws_col;