aboutsummaryrefslogtreecommitdiff
path: root/libbb/xfuncs_printf.c
blob: 7069a7c8e949e20a7745a35eb46c5193f708b28e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
/* vi: set sw=4 ts=4: */
/*
 * Utility routines.
 *
 * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
 * Copyright (C) 2006 Rob Landley
 * Copyright (C) 2006 Denys Vlasenko
 *
 * Licensed under GPL version 2, see file LICENSE in this tarball for details.
 */

/* We need to have separate xfuncs.c and xfuncs_printf.c because
 * with current linkers, even with section garbage collection,
 * if *.o module references any of XXXprintf functions, you pull in
 * entire printf machinery. Even if you do not use the function
 * which uses XXXprintf.
 *
 * xfuncs.c contains functions (not necessarily xfuncs)
 * which do not pull in printf, directly or indirectly.
 * xfunc_printf.c contains those which do.
 */

#include "libbb.h"


/* All the functions starting with "x" call bb_error_msg_and_die() if they
 * fail, so callers never need to check for errors.  If it returned, it
 * succeeded. */

#ifndef DMALLOC
/* dmalloc provides variants of these that do abort() on failure.
 * Since dmalloc's prototypes overwrite the impls here as they are
 * included after these prototypes in libbb.h, all is well.
 */
// Warn if we can't allocate size bytes of memory.
void* FAST_FUNC malloc_or_warn(size_t size)
{
	void *ptr = malloc(size);
	if (ptr == NULL && size != 0)
		bb_error_msg(bb_msg_memory_exhausted);
	return ptr;
}

// Die if we can't allocate size bytes of memory.
void* FAST_FUNC xmalloc(size_t size)
{
	void *ptr = malloc(size);
	if (ptr == NULL && size != 0)
		bb_error_msg_and_die(bb_msg_memory_exhausted);
	return ptr;
}

// Die if we can't resize previously allocated memory.  (This returns a pointer
// to the new memory, which may or may not be the same as the old memory.
// It'll copy the contents to a new chunk and free the old one if necessary.)
void* FAST_FUNC xrealloc(void *ptr, size_t size)
{
	ptr = realloc(ptr, size);
	if (ptr == NULL && size != 0)
		bb_error_msg_and_die(bb_msg_memory_exhausted);
	return ptr;
}
#endif /* DMALLOC */

// Die if we can't allocate and zero size bytes of memory.
void* FAST_FUNC xzalloc(size_t size)
{
	void *ptr = xmalloc(size);
	memset(ptr, 0, size);
	return ptr;
}

// Die if we can't copy a string to freshly allocated memory.
char* FAST_FUNC xstrdup(const char *s)
{
	char *t;

	if (s == NULL)
		return NULL;

	t = strdup(s);

	if (t == NULL)
		bb_error_msg_and_die(bb_msg_memory_exhausted);

	return t;
}

// Die if we can't allocate n+1 bytes (space for the null terminator) and copy
// the (possibly truncated to length n) string into it.
char* FAST_FUNC xstrndup(const char *s, int n)
{
	int m;
	char *t;

	if (ENABLE_DEBUG && s == NULL)
		bb_error_msg_and_die("xstrndup bug");

	/* We can just xmalloc(n+1) and strncpy into it, */
	/* but think about xstrndup("abc", 10000) wastage! */
	m = n;
	t = (char*) s;
	while (m) {
		if (!*t) break;
		m--;
		t++;
	}
	n -= m;
	t = xmalloc(n + 1);
	t[n] = '\0';

	return memcpy(t, s, n);
}

// Die if we can't open a file and return a FILE* to it.
// Notice we haven't got xfread(), This is for use with fscanf() and friends.
FILE* FAST_FUNC xfopen(const char *path, const char *mode)
{
	FILE *fp = fopen(path, mode);
	if (fp == NULL)
		bb_perror_msg_and_die("can't open '%s'", path);
	return fp;
}

// Die if we can't open a file and return a fd.
int FAST_FUNC xopen3(const char *pathname, int flags, int mode)
{
	int ret;

	ret = open(pathname, flags, mode);
	if (ret < 0) {
		bb_perror_msg_and_die("can't open '%s'", pathname);
	}
	return ret;
}

// Die if we can't open an existing file and return a fd.
int FAST_FUNC xopen(const char *pathname, int flags)
{
	return xopen3(pathname, flags, 0666);
}

/* Die if we can't open an existing file readonly with O_NONBLOCK
 * and return the fd.
 * Note that for ioctl O_RDONLY is sufficient.
 */
int FAST_FUNC xopen_nonblocking(const char *pathname)
{
	return xopen(pathname, O_RDONLY | O_NONBLOCK);
}

// Warn if we can't open a file and return a fd.
int FAST_FUNC open3_or_warn(const char *pathname, int flags, int mode)
{
	int ret;

	ret = open(pathname, flags, mode);
	if (ret < 0) {
		bb_perror_msg("can't open '%s'", pathname);
	}
	return ret;
}

// Warn if we can't open a file and return a fd.
int FAST_FUNC open_or_warn(const char *pathname, int flags)
{
	return open3_or_warn(pathname, flags, 0666);
}

void FAST_FUNC xunlink(const char *pathname)
{
	if (unlink(pathname))
		bb_perror_msg_and_die("can't remove file '%s'", pathname);
}

void FAST_FUNC xrename(const char *oldpath, const char *newpath)
{
	if (rename(oldpath, newpath))
		bb_perror_msg_and_die("can't move '%s' to '%s'", oldpath, newpath);
}

int FAST_FUNC rename_or_warn(const char *oldpath, const char *newpath)
{
	int n = rename(oldpath, newpath);
	if (n)
		bb_perror_msg("can't move '%s' to '%s'", oldpath, newpath);
	return n;
}

void FAST_FUNC xpipe(int filedes[2])
{
	if (pipe(filedes))
		bb_perror_msg_and_die("can't create pipe");
}

void FAST_FUNC xdup2(int from, int to)
{
	if (dup2(from, to) != to)
		bb_perror_msg_and_die("can't duplicate file descriptor");
}

// "Renumber" opened fd
void FAST_FUNC xmove_fd(int from, int to)
{
	if (from == to)
		return;
	xdup2(from, to);
	close(from);
}

// Die with an error message if we can't write the entire buffer.
void FAST_FUNC xwrite(int fd, const void *buf, size_t count)
{
	if (count) {
		ssize_t size = full_write(fd, buf, count);
		if ((size_t)size != count)
			bb_error_msg_and_die("short write");
	}
}
void FAST_FUNC xwrite_str(int fd, const char *str)
{
	xwrite(fd, str, strlen(str));
}

void FAST_FUNC xclose(int fd)
{
	if (close(fd))
		bb_perror_msg_and_die("close failed");
}

// Die with an error message if we can't lseek to the right spot.
off_t FAST_FUNC xlseek(int fd, off_t offset, int whence)
{
	off_t off = lseek(fd, offset, whence);
	if (off == (off_t)-1) {
		if (whence == SEEK_SET)
			bb_perror_msg_and_die("lseek(%"OFF_FMT"u)", offset);
		bb_perror_msg_and_die("lseek");
	}
	return off;
}

// Die with supplied filename if this FILE* has ferror set.
void FAST_FUNC die_if_ferror(FILE *fp, const char *fn)
{
	if (ferror(fp)) {
		/* ferror doesn't set useful errno */
		bb_error_msg_and_die("%s: I/O error", fn);
	}
}

// Die with an error message if stdout has ferror set.
void FAST_FUNC die_if_ferror_stdout(void)
{
	die_if_ferror(stdout, bb_msg_standard_output);
}

int FAST_FUNC fflush_all(void)
{
	return fflush(NULL);
}


int FAST_FUNC bb_putchar(int ch)
{
	return putchar(ch);
}

/* Die with an error message if we can't copy an entire FILE* to stdout,
 * then close that file. */
void FAST_FUNC xprint_and_close_file(FILE *file)
{
	fflush_all();
	// copyfd outputs error messages for us.
	if (bb_copyfd_eof(fileno(file), STDOUT_FILENO) == -1)
		xfunc_die();

	fclose(file);
}

// Die with an error message if we can't malloc() enough space and do an
// sprintf() into that space.
char* FAST_FUNC xasprintf(const char *format, ...)
{
	va_list p;
	int r;
	char *string_ptr;

	va_start(p, format);
	r = vasprintf(&string_ptr, format, p);
	va_end(p);

	if (r < 0)
		bb_error_msg_and_die(bb_msg_memory_exhausted);
	return string_ptr;
}

void FAST_FUNC xsetenv(const char *key, const char *value)
{
	if (setenv(key, value, 1))
		bb_error_msg_and_die(bb_msg_memory_exhausted);
}

/* Handles "VAR=VAL" strings, even those which are part of environ
 * _right now_
 */
void FAST_FUNC bb_unsetenv(const char *var)
{
	char *tp = strchr(var, '=');

	if (!tp) {
		unsetenv(var);
		return;
	}

	/* In case var was putenv'ed, we can't replace '='
	 * with NUL and unsetenv(var) - it won't work,
	 * env is modified by the replacement, unsetenv
	 * sees "VAR" instead of "VAR=VAL" and does not remove it!
	 * horror :( */
	tp = xstrndup(var, tp - var);
	unsetenv(tp);
	free(tp);
}

void FAST_FUNC bb_unsetenv_and_free(char *var)
{
	bb_unsetenv(var);
	free(var);
}

// Die with an error message if we can't set gid.  (Because resource limits may
// limit this user to a given number of processes, and if that fills up the
// setgid() will fail and we'll _still_be_root_, which is bad.)
void FAST_FUNC xsetgid(gid_t gid)
{
	if (setgid(gid)) bb_perror_msg_and_die("setgid");
}

// Die with an error message if we can't set uid.  (See xsetgid() for why.)
void FAST_FUNC xsetuid(uid_t uid)
{
	if (setuid(uid)) bb_perror_msg_and_die("setuid");
}

// Die if we can't chdir to a new path.
void FAST_FUNC xchdir(const char *path)
{
	if (chdir(path))
		bb_perror_msg_and_die("chdir(%s)", path);
}

void FAST_FUNC xchroot(const char *path)
{
	if (chroot(path))
		bb_perror_msg_and_die("can't change root directory to %s", path);
}

// Print a warning message if opendir() fails, but don't die.
DIR* FAST_FUNC warn_opendir(const char *path)
{
	DIR *dp;

	dp = opendir(path);
	if (!dp)
		bb_perror_msg("can't open '%s'", path);
	return dp;
}

// Die with an error message if opendir() fails.
DIR* FAST_FUNC xopendir(const char *path)
{
	DIR *dp;

	dp = opendir(path);
	if (!dp)
		bb_perror_msg_and_die("can't open '%s'", path);
	return dp;
}

// Die with an error message if we can't open a new socket.
int FAST_FUNC xsocket(int domain, int type, int protocol)
{
	int r = socket(domain, type, protocol);

	if (r < 0) {
		/* Hijack vaguely related config option */
#if ENABLE_VERBOSE_RESOLUTION_ERRORS
		const char *s = "INET";
		if (domain == AF_PACKET) s = "PACKET";
		if (domain == AF_NETLINK) s = "NETLINK";
IF_FEATURE_IPV6(if (domain == AF_INET6) s = "INET6";)
		bb_perror_msg_and_die("socket(AF_%s,%d,%d)", s, type, protocol);
#else
		bb_perror_msg_and_die("socket");
#endif
	}

	return r;
}

// Die with an error message if we can't bind a socket to an address.
void FAST_FUNC xbind(int sockfd, struct sockaddr *my_addr, socklen_t addrlen)
{
	if (bind(sockfd, my_addr, addrlen)) bb_perror_msg_and_die("bind");
}

// Die with an error message if we can't listen for connections on a socket.
void FAST_FUNC xlisten(int s, int backlog)
{
	if (listen(s, backlog)) bb_perror_msg_and_die("listen");
}

/* Die with an error message if sendto failed.
 * Return bytes sent otherwise  */
ssize_t FAST_FUNC xsendto(int s, const void *buf, size_t len, const struct sockaddr *to,
				socklen_t tolen)
{
	ssize_t ret = sendto(s, buf, len, 0, to, tolen);
	if (ret < 0) {
		if (ENABLE_FEATURE_CLEAN_UP)
			close(s);
		bb_perror_msg_and_die("sendto");
	}
	return ret;
}

// xstat() - a stat() which dies on failure with meaningful error message
void FAST_FUNC xstat(const char *name, struct stat *stat_buf)
{
	if (stat(name, stat_buf))
		bb_perror_msg_and_die("can't stat '%s'", name);
}

// selinux_or_die() - die if SELinux is disabled.
void FAST_FUNC selinux_or_die(void)
{
#if ENABLE_SELINUX
	int rc = is_selinux_enabled();
	if (rc == 0) {
		bb_error_msg_and_die("SELinux is disabled");
	} else if (rc < 0) {
		bb_error_msg_and_die("is_selinux_enabled() failed");
	}
#else
	bb_error_msg_and_die("SELinux support is disabled");
#endif
}

int FAST_FUNC ioctl_or_perror_and_die(int fd, unsigned request, void *argp, const char *fmt,...)
{
	int ret;
	va_list p;

	ret = ioctl(fd, request, argp);
	if (ret < 0) {
		va_start(p, fmt);
		bb_verror_msg(fmt, p, strerror(errno));
		/* xfunc_die can actually longjmp, so be nice */
		va_end(p);
		xfunc_die();
	}
	return ret;
}

int FAST_FUNC ioctl_or_perror(int fd, unsigned request, void *argp, const char *fmt,...)
{
	va_list p;
	int ret = ioctl(fd, request, argp);

	if (ret < 0) {
		va_start(p, fmt);
		bb_verror_msg(fmt, p, strerror(errno));
		va_end(p);
	}
	return ret;
}

#if ENABLE_IOCTL_HEX2STR_ERROR
int FAST_FUNC bb_ioctl_or_warn(int fd, unsigned request, void *argp, const char *ioctl_name)
{
	int ret;

	ret = ioctl(fd, request, argp);
	if (ret < 0)
		bb_simple_perror_msg(ioctl_name);
	return ret;
}
int FAST_FUNC bb_xioctl(int fd, unsigned request, void *argp, const char *ioctl_name)
{
	int ret;

	ret = ioctl(fd, request, argp);
	if (ret < 0)
		bb_simple_perror_msg_and_die(ioctl_name);
	return ret;
}
#else
int FAST_FUNC bb_ioctl_or_warn(int fd, unsigned request, void *argp)
{
	int ret;

	ret = ioctl(fd, request, argp);
	if (ret < 0)
		bb_perror_msg("ioctl %#x failed", request);
	return ret;
}
int FAST_FUNC bb_xioctl(int fd, unsigned request, void *argp)
{
	int ret;

	ret = ioctl(fd, request, argp);
	if (ret < 0)
		bb_perror_msg_and_die("ioctl %#x failed", request);
	return ret;
}
#endif

char* FAST_FUNC xmalloc_ttyname(int fd)
{
	char *buf = xzalloc(128);
	int r = ttyname_r(fd, buf, 127);
	if (r) {
		free(buf);
		buf = NULL;
	}
	return buf;
}

void FAST_FUNC generate_uuid(uint8_t *buf)
{
	/* http://www.ietf.org/rfc/rfc4122.txt
	 *  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
	 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	 * |                          time_low                             |
	 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	 * |       time_mid                |         time_hi_and_version   |
	 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	 * |clk_seq_and_variant            |         node (0-1)            |
	 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	 * |                         node (2-5)                            |
	 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	 * IOW, uuid has this layout:
	 * uint32_t time_low (big endian)
	 * uint16_t time_mid (big endian)
	 * uint16_t time_hi_and_version (big endian)
	 *  version is a 4-bit field:
	 *   1 Time-based
	 *   2 DCE Security, with embedded POSIX UIDs
	 *   3 Name-based (MD5)
	 *   4 Randomly generated
	 *   5 Name-based (SHA-1)
	 * uint16_t clk_seq_and_variant (big endian)
	 *  variant is a 3-bit field:
	 *   0xx Reserved, NCS backward compatibility
	 *   10x The variant specified in rfc4122
	 *   110 Reserved, Microsoft backward compatibility
	 *   111 Reserved for future definition
	 * uint8_t node[6]
	 *
	 * For version 4, these bits are set/cleared:
	 * time_hi_and_version & 0x0fff | 0x4000
	 * clk_seq_and_variant & 0x3fff | 0x8000
	 */
	pid_t pid;
	int i;

	i = open("/dev/urandom", O_RDONLY);
	if (i >= 0) {
		read(i, buf, 16);
		close(i);
	}
	/* Paranoia. /dev/urandom may be missing.
	 * rand() is guaranteed to generate at least [0, 2^15) range,
	 * but lowest bits in some libc are not so "random".  */
	srand(monotonic_us()); /* pulls in printf */
	pid = getpid();
	while (1) {
		for (i = 0; i < 16; i++)
			buf[i] ^= rand() >> 5;
		if (pid == 0)
			break;
		srand(pid);
		pid = 0;
	}

	/* version = 4 */
	buf[4 + 2    ] = (buf[4 + 2    ] & 0x0f) | 0x40;
	/* variant = 10x */
	buf[4 + 2 + 2] = (buf[4 + 2 + 2] & 0x3f) | 0x80;
}

#if BB_MMU
pid_t FAST_FUNC xfork(void)
{
	pid_t pid;
	pid = fork();
	if (pid < 0) /* wtf? */
		bb_perror_msg_and_die("vfork"+1);
	return pid;
}
#endif