summaryrefslogtreecommitdiffstats
path: root/util.c
blob: d825554d7fe756673ce5de54683b4e9008620e9e (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
/****************************************************************************
 * bfs                                                                      *
 * Copyright (C) 2016-2017 Tavian Barnes <tavianator@tavianator.com>        *
 *                                                                          *
 * Permission to use, copy, modify, and/or distribute this software for any *
 * purpose with or without fee is hereby granted.                           *
 *                                                                          *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES *
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF         *
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR  *
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES   *
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN    *
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF  *
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.           *
 ****************************************************************************/

#include "util.h"
#include "bftw.h"
#include "dstring.h"
#include <errno.h>
#include <fcntl.h>
#include <langinfo.h>
#include <regex.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>

int xreaddir(DIR *dir, struct dirent **de) {
	errno = 0;
	*de = readdir(dir);
	if (!*de && errno != 0) {
		return -1;
	} else {
		return 0;
	}
}

char *xreadlinkat(int fd, const char *path, size_t size) {
	++size; // NUL-terminator
	ssize_t len;
	char *name = NULL;

	while (true) {
		char *new_name = realloc(name, size);
		if (!new_name) {
			goto error;
		}
		name = new_name;

		len = readlinkat(fd, path, name, size);
		if (len < 0) {
			goto error;
		} else if (len >= size) {
			size *= 2;
		} else {
			break;
		}
	}

	name[len] = '\0';
	return name;

error:
	free(name);
	return NULL;
}

bool isopen(int fd) {
	return fcntl(fd, F_GETFD) >= 0 || errno != EBADF;
}

int redirect(int fd, const char *path, int flags, ...) {
	close(fd);

	mode_t mode = 0;
	if (flags & O_CREAT) {
		va_list args;
		va_start(args, flags);

		// Use int rather than mode_t, because va_arg must receive a
		// fully-promoted type
		mode = va_arg(args, int);

		va_end(args);
	}

	int ret = open(path, flags, mode);

	if (ret >= 0 && ret != fd) {
		int other = ret;
		ret = dup2(other, fd);
		if (close(other) != 0) {
			ret = -1;
		}
	}

	return ret;
}

int dup_cloexec(int fd) {
#ifdef F_DUPFD_CLOEXEC
	return fcntl(fd, F_DUPFD_CLOEXEC, 0);
#else
	int ret = dup(fd);
	if (ret < 0) {
		return -1;
	}

	if (fcntl(ret, F_SETFD, FD_CLOEXEC) == -1) {
		close(ret);
		return -1;
	}

	return ret;
#endif
}

char *xregerror(int err, const regex_t *regex) {
	size_t len = regerror(err, regex, NULL, 0);
	char *str = malloc(len);
	if (str) {
		regerror(err, regex, str, len);
	}
	return str;
}

int xlocaltime(const time_t *timep, struct tm *result) {
	// Should be called before localtime_r() according to POSIX.1-2004
	tzset();

	if (localtime_r(timep, result)) {
		return 0;
	} else {
		return -1;
	}
}

void format_mode(mode_t mode, char str[11]) {
	strcpy(str, "----------");

	switch (mode_to_typeflag(mode)) {
	case BFTW_BLK:
		str[0] = 'b';
		break;
	case BFTW_CHR:
		str[0] = 'c';
		break;
	case BFTW_DIR:
		str[0] = 'd';
		break;
	case BFTW_DOOR:
		str[0] = 'D';
		break;
	case BFTW_FIFO:
		str[0] = 'p';
		break;
	case BFTW_LNK:
		str[0] = 'l';
		break;
	case BFTW_SOCK:
		str[0] = 's';
		break;
	default:
		break;
	}

	if (mode & 00400) {
		str[1] = 'r';
	}
	if (mode & 00200) {
		str[2] = 'w';
	}
	if ((mode & 04100) == 04000) {
		str[3] = 'S';
	} else if (mode & 04000) {
		str[3] = 's';
	} else if (mode & 00100) {
		str[3] = 'x';
	}

	if (mode & 00040) {
		str[4] = 'r';
	}
	if (mode & 00020) {
		str[5] = 'w';
	}
	if ((mode & 02010) == 02000) {
		str[6] = 'S';
	} else if (mode & 02000) {
		str[6] = 's';
	} else if (mode & 00010) {
		str[6] = 'x';
	}

	if (mode & 00004) {
		str[7] = 'r';
	}
	if (mode & 00002) {
		str[8] = 'w';
	}
	if ((mode & 01001) == 01000) {
		str[9] = 'T';
	} else if (mode & 01000) {
		str[9] = 't';
	} else if (mode & 00001) {
		str[9] = 'x';
	}
}

const char *xbasename(const char *path) {
	const char *i;

	// Skip trailing slashes
	for (i = path + strlen(path); i > path && i[-1] == '/'; --i);

	// Find the beginning of the name
	for (; i > path && i[-1] != '/'; --i);

	// Skip leading slashes
	for (; i[0] == '/' && i[1]; ++i);

	return i;
}

int xfstatat(int fd, const char *path, struct stat *buf, int *flags) {
	int ret = fstatat(fd, path, buf, *flags);

	if (ret != 0 && !(*flags & AT_SYMLINK_NOFOLLOW) && (errno == ENOENT || errno == ENOTDIR)) {
		*flags |= AT_SYMLINK_NOFOLLOW;
		ret = fstatat(fd, path, buf, *flags);
	}

	return ret;
}

enum bftw_typeflag mode_to_typeflag(mode_t mode) {
	switch (mode & S_IFMT) {
#ifdef S_IFBLK
	case S_IFBLK:
		return BFTW_BLK;
#endif
#ifdef S_IFCHR
	case S_IFCHR:
		return BFTW_CHR;
#endif
#ifdef S_IFDIR
	case S_IFDIR:
		return BFTW_DIR;
#endif
#ifdef S_IFDOOR
	case S_IFDOOR:
		return BFTW_DOOR;
#endif
#ifdef S_IFIFO
	case S_IFIFO:
		return BFTW_FIFO;
#endif
#ifdef S_IFLNK
	case S_IFLNK:
		return BFTW_LNK;
#endif
#ifdef S_IFPORT
	case S_IFPORT:
		return BFTW_PORT;
#endif
#ifdef S_IFREG
	case S_IFREG:
		return BFTW_REG;
#endif
#ifdef S_IFSOCK
	case S_IFSOCK:
		return BFTW_SOCK;
#endif
#ifdef S_IFWHT
	case S_IFWHT:
		return BFTW_WHT;
#endif

	default:
		return BFTW_UNKNOWN;
	}
}

enum bftw_typeflag dirent_to_typeflag(const struct dirent *de) {
#if defined(_DIRENT_HAVE_D_TYPE) || defined(DT_UNKNOWN)
	switch (de->d_type) {
#ifdef DT_BLK
	case DT_BLK:
		return BFTW_BLK;
#endif
#ifdef DT_CHR
	case DT_CHR:
		return BFTW_CHR;
#endif
#ifdef DT_DIR
	case DT_DIR:
		return BFTW_DIR;
#endif
#ifdef DT_DOOR
	case DT_DOOR:
		return BFTW_DOOR;
#endif
#ifdef DT_FIFO
	case DT_FIFO:
		return BFTW_FIFO;
#endif
#ifdef DT_LNK
	case DT_LNK:
		return BFTW_LNK;
#endif
#ifdef DT_PORT
	case DT_PORT:
		return BFTW_PORT;
#endif
#ifdef DT_REG
	case DT_REG:
		return BFTW_REG;
#endif
#ifdef DT_SOCK
	case DT_SOCK:
		return BFTW_SOCK;
#endif
#ifdef DT_WHT
	case DT_WHT:
		return BFTW_WHT;
#endif
	}
#endif

	return BFTW_UNKNOWN;
}

/** Read a line from standard input. */
static char *xgetline() {
	char *line = dstralloc(0);
	if (!line) {
		return NULL;
	}

	while (true) {
		int c = getchar();
		if (c == '\n' || c == EOF) {
			break;
		}

		if (dstrapp(&line, c) != 0) {
			goto error;
		}
	}

	return line;

error:
	dstrfree(line);
	return NULL;
}

/** Compile and execute a regular expression for xrpmatch(). */
static int xrpregex(nl_item item, const char *response) {
	const char *pattern = nl_langinfo(item);
	if (!pattern) {
		return REG_BADPAT;
	}

	regex_t regex;
	int ret = regcomp(&regex, pattern, REG_EXTENDED);
	if (ret != 0) {
		return ret;
	}

	ret = regexec(&regex, response, 0, NULL, 0);
	regfree(&regex);
	return ret;
}

/** Check if a response is affirmative or negative. */
static int xrpmatch(const char *response) {
	int ret = xrpregex(NOEXPR, response);
	if (ret == 0) {
		return 0;
	} else if (ret != REG_NOMATCH) {
		return -1;
	}

	ret = xrpregex(YESEXPR, response);
	if (ret == 0) {
		return 1;
	} else if (ret != REG_NOMATCH) {
		return -1;
	}

	// Failsafe: always handle y/n
	char c = response[0];
	if (c == 'n' || c == 'N') {
		return 0;
	} else if (c == 'y' || c == 'Y') {
		return 1;
	} else {
		return -1;
	}
}

int ynprompt() {
	fflush(stderr);

	char *line = xgetline();
	int ret = line ? xrpmatch(line) : -1;
	dstrfree(line);
	return ret;
}