1 /* $OpenBSD: conf.c,v 1.107 2017/10/27 08:29:32 mpi Exp $	 */
2 /* $EOM: conf.c,v 1.48 2000/12/04 02:04:29 angelos Exp $	 */
3 
4 /*
5  * Copyright (c) 1998, 1999, 2000, 2001 Niklas Hallqvist.  All rights reserved.
6  * Copyright (c) 2000, 2001, 2002 Håkan Olsson.  All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #include <sys/types.h>
30 #include <sys/queue.h>
31 #include <sys/stat.h>
32 
33 #include <ctype.h>
34 #include <fcntl.h>
35 #include <stdarg.h>
36 #include <stdio.h>
37 #include <stdlib.h>
38 #include <string.h>
39 #include <unistd.h>
40 #include <errno.h>
41 
42 #include "got_error.h"
43 
44 #include "got_lib_gitconfig.h"
45 
46 #ifndef nitems
47 #define nitems(_a) (sizeof(_a) / sizeof((_a)[0]))
48 #endif
49 
50 #define LOG_MISC	0
51 #define LOG_REPORT	1
52 #ifdef GITCONFIG_DEBUG
53 #define LOG_DBG(x) log_debug x
54 #else
55 #define LOG_DBG(x)
56 #endif
57 
58 #define log_print printf
59 #define log_error printf
60 
61 #ifdef GITCONFIG_DEBUG
62 static void
63 log_debug(int cls, int level, const char *fmt, ...)
64 {
65 	va_list         ap;
66 
67 	va_start(ap, fmt);
68 	vfprintf(stderr, fmt, ap);
69 	va_end(ap);
70 	putc('\n', stderr);
71 }
72 #endif
73 
74 struct got_gitconfig_trans {
75 	TAILQ_ENTRY(got_gitconfig_trans) link;
76 	int	 trans;
77 	enum got_gitconfig_op {
78 		CONF_SET, CONF_REMOVE, CONF_REMOVE_SECTION
79 	}	 op;
80 	char	*section;
81 	char	*tag;
82 	char	*value;
83 	int	 override;
84 	int	 is_default;
85 };
86 
87 TAILQ_HEAD(got_gitconfig_trans_head, got_gitconfig_trans);
88 
89 struct got_gitconfig_binding {
90 	LIST_ENTRY(got_gitconfig_binding) link;
91 	char	*section;
92 	char	*tag;
93 	char	*value;
94 	int	 is_default;
95 };
96 
97 LIST_HEAD(got_gitconfig_bindings, got_gitconfig_binding);
98 
99 struct got_gitconfig {
100 	struct got_gitconfig_bindings bindings[256];
101 	struct got_gitconfig_trans_head trans_queue;
102 	char	*addr;
103 	int	seq;
104 };
105 
106 static __inline__ u_int8_t
107 conf_hash(const char *s)
108 {
109 	u_int8_t hash = 0;
110 
111 	while (*s) {
112 		hash = ((hash << 1) | (hash >> 7)) ^ tolower((unsigned char)*s);
113 		s++;
114 	}
115 	return hash;
116 }
117 
118 /*
119  * Insert a tag-value combination from LINE (the equal sign is at POS)
120  */
121 static int
122 conf_remove_now(struct got_gitconfig *conf, char *section, char *tag)
123 {
124 	struct got_gitconfig_binding *cb, *next;
125 
126 	for (cb = LIST_FIRST(&conf->bindings[conf_hash(section)]); cb;
127 	    cb = next) {
128 		next = LIST_NEXT(cb, link);
129 		if (strcasecmp(cb->section, section) == 0 &&
130 		    strcasecmp(cb->tag, tag) == 0) {
131 			LIST_REMOVE(cb, link);
132 			LOG_DBG((LOG_MISC, 95, "[%s]:%s->%s removed", section,
133 			    tag, cb->value));
134 			free(cb->section);
135 			free(cb->tag);
136 			free(cb->value);
137 			free(cb);
138 			return 0;
139 		}
140 	}
141 	return 1;
142 }
143 
144 static int
145 conf_remove_section_now(struct got_gitconfig *conf, char *section)
146 {
147 	struct got_gitconfig_binding *cb, *next;
148 	int	unseen = 1;
149 
150 	for (cb = LIST_FIRST(&conf->bindings[conf_hash(section)]); cb;
151 	    cb = next) {
152 		next = LIST_NEXT(cb, link);
153 		if (strcasecmp(cb->section, section) == 0) {
154 			unseen = 0;
155 			LIST_REMOVE(cb, link);
156 			LOG_DBG((LOG_MISC, 95, "[%s]:%s->%s removed", section,
157 			    cb->tag, cb->value));
158 			free(cb->section);
159 			free(cb->tag);
160 			free(cb->value);
161 			free(cb);
162 		}
163 	}
164 	return unseen;
165 }
166 
167 /*
168  * Insert a tag-value combination from LINE (the equal sign is at POS)
169  * into SECTION of our configuration database.
170  */
171 static int
172 conf_set_now(struct got_gitconfig *conf, char *section, char *tag,
173     char *value, int override, int is_default)
174 {
175 	struct got_gitconfig_binding *node = 0;
176 
177 	if (override)
178 		conf_remove_now(conf, section, tag);
179 	else if (got_gitconfig_get_str(conf, section, tag)) {
180 		if (!is_default)
181 			LOG_DBG((LOG_MISC, 95,
182 			    "conf_set_now: duplicate tag [%s]:%s, "
183 			    "ignoring...", section, tag));
184 		return 1;
185 	}
186 	node = calloc(1, sizeof *node);
187 	if (!node) {
188 		log_error("conf_set_now: calloc (1, %lu) failed",
189 		    (unsigned long)sizeof *node);
190 		return 1;
191 	}
192 	node->section = node->tag = node->value = NULL;
193 	if ((node->section = strdup(section)) == NULL)
194 		goto fail;
195 	if ((node->tag = strdup(tag)) == NULL)
196 		goto fail;
197 	if ((node->value = strdup(value)) == NULL)
198 		goto fail;
199 	node->is_default = is_default;
200 
201 	LIST_INSERT_HEAD(&conf->bindings[conf_hash(section)], node, link);
202 	LOG_DBG((LOG_MISC, 95, "conf_set_now: [%s]:%s->%s", node->section,
203 	    node->tag, node->value));
204 	return 0;
205 fail:
206 	free(node->value);
207 	free(node->tag);
208 	free(node->section);
209 	free(node);
210 	return 1;
211 }
212 
213 /*
214  * Parse the line LINE of SZ bytes.  Skip Comments, recognize section
215  * headers and feed tag-value pairs into our configuration database.
216  */
217 static const struct got_error *
218 conf_parse_line(char **section, struct got_gitconfig *conf, int trans,
219     char *line, int ln, size_t sz)
220 {
221 	char	*val;
222 	size_t	 i;
223 	int	 j;
224 
225 	/* Lines starting with '#' or ';' are comments.  */
226 	if (*line == '#' || *line == ';')
227 		return NULL;
228 
229 	/* '[section]' parsing...  */
230 	if (*line == '[') {
231 		for (i = 1; i < sz; i++)
232 			if (line[i] == ']')
233 				break;
234 		free(*section);
235 		if (i == sz) {
236 			log_print("conf_parse_line: %d:"
237 			    "unmatched ']', ignoring until next section", ln);
238 			*section = NULL;
239 			return NULL;
240 		}
241 		*section = strndup(line + 1, i - 1);
242 		if (*section == NULL)
243 			return got_error_from_errno("strndup");
244 		return NULL;
245 	}
246 	while (isspace((unsigned char)*line))
247 		line++;
248 
249 	/* Deal with assignments.  */
250 	for (i = 0; i < sz; i++)
251 		if (line[i] == '=') {
252 			/* If no section, we are ignoring the lines.  */
253 			if (!*section) {
254 				log_print("conf_parse_line: %d: ignoring line "
255 				    "due to no section", ln);
256 				return NULL;
257 			}
258 			line[strcspn(line, " \t=")] = '\0';
259 			val = line + i + 1 + strspn(line + i + 1, " \t");
260 			/* Skip trailing whitespace, if any */
261 			for (j = sz - (val - line) - 1; j > 0 &&
262 			    isspace((unsigned char)val[j]); j--)
263 				val[j] = '\0';
264 			/* XXX Perhaps should we not ignore errors?  */
265 			got_gitconfig_set(conf, trans, *section, line, val,
266 			    0, 0);
267 			return NULL;
268 		}
269 	/* Other non-empty lines are weird.  */
270 	i = strspn(line, " \t");
271 	if (line[i])
272 		log_print("conf_parse_line: %d: syntax error", ln);
273 
274 	return NULL;
275 }
276 
277 /* Parse the mapped configuration file.  */
278 static const struct got_error *
279 conf_parse(struct got_gitconfig *conf, int trans, char *buf, size_t sz)
280 {
281 	const struct got_error *err = NULL;
282 	char	*cp = buf;
283 	char	*bufend = buf + sz;
284 	char	*line, *section = NULL;
285 	int	ln = 1;
286 
287 	line = cp;
288 	while (cp < bufend) {
289 		if (*cp == '\n') {
290 			/* Check for escaped newlines.  */
291 			if (cp > buf && *(cp - 1) == '\\')
292 				*(cp - 1) = *cp = ' ';
293 			else {
294 				*cp = '\0';
295 				err = conf_parse_line(&section, conf, trans,
296 				    line, ln, cp - line);
297 				if (err)
298 					return err;
299 				line = cp + 1;
300 			}
301 			ln++;
302 		}
303 		cp++;
304 	}
305 	if (cp != line)
306 		log_print("conf_parse: last line unterminated, ignored.");
307 	return NULL;
308 }
309 
310 const struct got_error *
311 got_gitconfig_open(struct got_gitconfig **conf, int fd)
312 {
313 	size_t i;
314 
315 	*conf = calloc(1, sizeof(**conf));
316 	if (*conf == NULL)
317 		return got_error_from_errno("malloc");
318 
319 	for (i = 0; i < nitems((*conf)->bindings); i++)
320 		LIST_INIT(&(*conf)->bindings[i]);
321 	TAILQ_INIT(&(*conf)->trans_queue);
322 	return got_gitconfig_reinit(*conf, fd);
323 }
324 
325 static void
326 conf_clear(struct got_gitconfig *conf)
327 {
328 	struct got_gitconfig_binding *cb;
329 	size_t i;
330 
331 	if (conf->addr) {
332 		for (i = 0; i < nitems(conf->bindings); i++)
333 			for (cb = LIST_FIRST(&conf->bindings[i]); cb;
334 			    cb = LIST_FIRST(&conf->bindings[i]))
335 				conf_remove_now(conf, cb->section, cb->tag);
336 		free(conf->addr);
337 		conf->addr = NULL;
338 	}
339 }
340 
341 /* Execute all queued operations for this transaction.  Cleanup.  */
342 static int
343 conf_end(struct got_gitconfig *conf, int transaction, int commit)
344 {
345 	struct got_gitconfig_trans *node, *next;
346 
347 	for (node = TAILQ_FIRST(&conf->trans_queue); node; node = next) {
348 		next = TAILQ_NEXT(node, link);
349 		if (node->trans == transaction) {
350 			if (commit)
351 				switch (node->op) {
352 				case CONF_SET:
353 					conf_set_now(conf, node->section,
354 					    node->tag, node->value,
355 					    node->override, node->is_default);
356 					break;
357 				case CONF_REMOVE:
358 					conf_remove_now(conf, node->section,
359 					    node->tag);
360 					break;
361 				case CONF_REMOVE_SECTION:
362 					conf_remove_section_now(conf, node->section);
363 					break;
364 				default:
365 					log_print("got_gitconfig_end: unknown "
366 					    "operation: %d", node->op);
367 				}
368 			TAILQ_REMOVE(&conf->trans_queue, node, link);
369 			free(node->section);
370 			free(node->tag);
371 			free(node->value);
372 			free(node);
373 		}
374 	}
375 	return 0;
376 }
377 
378 
379 void
380 got_gitconfig_close(struct got_gitconfig *conf)
381 {
382 	conf_clear(conf);
383 	free(conf);
384 }
385 
386 static int
387 conf_begin(struct got_gitconfig *conf)
388 {
389 	return ++conf->seq;
390 }
391 
392 /* Open the config file and map it into our address space, then parse it.  */
393 const struct got_error *
394 got_gitconfig_reinit(struct got_gitconfig *conf, int fd)
395 {
396 	const struct got_error *err = NULL;
397 	int	 trans;
398 	size_t	 sz;
399 	char	*new_conf_addr = 0;
400 	struct stat st;
401 
402 	if (fstat(fd, &st)) {
403 		err = got_error_from_errno("fstat");
404 		goto fail;
405 	}
406 
407 	sz = st.st_size;
408 	new_conf_addr = malloc(sz);
409 	if (new_conf_addr == NULL) {
410 		err = got_error_from_errno("malloc");
411 		goto fail;
412 	}
413 	/* XXX I assume short reads won't happen here.  */
414 	if (read(fd, new_conf_addr, sz) != (int)sz) {
415 		err = got_error_from_errno("read");
416 		goto fail;
417 	}
418 
419 	trans = conf_begin(conf);
420 
421 	err = conf_parse(conf, trans, new_conf_addr, sz);
422 	if (err)
423 		goto fail;
424 
425 	/* Free potential existing configuration.  */
426 	conf_clear(conf);
427 	conf_end(conf, trans, 1);
428 	conf->addr = new_conf_addr;
429 	return NULL;
430 
431 fail:
432 	free(new_conf_addr);
433 	return err;
434 }
435 
436 /*
437  * Return the numeric value denoted by TAG in section SECTION or DEF
438  * if that tag does not exist.
439  */
440 int
441 got_gitconfig_get_num(struct got_gitconfig *conf, const char *section,
442     const char *tag, int def)
443 {
444 	char	*value = got_gitconfig_get_str(conf, section, tag);
445 
446 	if (value)
447 		return atoi(value);
448 	return def;
449 }
450 
451 /* Validate X according to the range denoted by TAG in section SECTION.  */
452 int
453 got_gitconfig_match_num(struct got_gitconfig *conf, char *section, char *tag,
454     int x)
455 {
456 	char	*value = got_gitconfig_get_str(conf, section, tag);
457 	int	 val, min, max, n;
458 
459 	if (!value)
460 		return 0;
461 	n = sscanf(value, "%d,%d:%d", &val, &min, &max);
462 	switch (n) {
463 	case 1:
464 		LOG_DBG((LOG_MISC, 95, "got_gitconfig_match_num: %s:%s %d==%d?",
465 		    section, tag, val, x));
466 		return x == val;
467 	case 3:
468 		LOG_DBG((LOG_MISC, 95, "got_gitconfig_match_num: %s:%s %d<=%d<=%d?",
469 		    section, tag, min, x, max));
470 		return min <= x && max >= x;
471 	default:
472 		log_error("got_gitconfig_match_num: section %s tag %s: invalid number "
473 		    "spec %s", section, tag, value);
474 	}
475 	return 0;
476 }
477 
478 /* Return the string value denoted by TAG in section SECTION.  */
479 char *
480 got_gitconfig_get_str(struct got_gitconfig *conf, const char *section,
481     const char *tag)
482 {
483 	struct got_gitconfig_binding *cb;
484 
485 	for (cb = LIST_FIRST(&conf->bindings[conf_hash(section)]); cb;
486 	    cb = LIST_NEXT(cb, link))
487 		if (strcasecmp(section, cb->section) == 0 &&
488 		    strcasecmp(tag, cb->tag) == 0) {
489 			LOG_DBG((LOG_MISC, 95, "got_gitconfig_get_str: [%s]:%s->%s",
490 			    section, tag, cb->value));
491 			return cb->value;
492 		}
493 	LOG_DBG((LOG_MISC, 95,
494 	    "got_gitconfig_get_str: configuration value not found [%s]:%s", section,
495 	    tag));
496 	return 0;
497 }
498 
499 const struct got_error *
500 got_gitconfig_get_section_list(struct got_gitconfig_list **sections,
501     struct got_gitconfig *conf)
502 {
503 	const struct got_error *err = NULL;
504 	struct got_gitconfig_list *list = NULL;
505 	struct got_gitconfig_list_node *node = 0;
506 	struct got_gitconfig_binding *cb;
507 	size_t i;
508 
509 	*sections = NULL;
510 
511 	list = malloc(sizeof *list);
512 	if (!list)
513 		return got_error_from_errno("malloc");
514 	TAILQ_INIT(&list->fields);
515 	list->cnt = 0;
516 	for (i = 0; i < nitems(conf->bindings); i++) {
517 		for (cb = LIST_FIRST(&conf->bindings[i]); cb;
518 		    cb = LIST_NEXT(cb, link)) {
519 			int section_present = 0;
520 			TAILQ_FOREACH(node, &list->fields, link) {
521 				if (strcmp(node->field, cb->section) == 0) {
522 					section_present = 1;
523 					break;
524 				}
525 			}
526 			if (section_present)
527 				continue;
528 			list->cnt++;
529 			node = calloc(1, sizeof *node);
530 			if (!node) {
531 				err = got_error_from_errno("calloc");
532 				goto cleanup;
533 			}
534 			node->field = strdup(cb->section);
535 			if (!node->field) {
536 				err = got_error_from_errno("strdup");
537 				goto cleanup;
538 			}
539 			TAILQ_INSERT_TAIL(&list->fields, node, link);
540 		}
541 	}
542 
543 	*sections = list;
544 	return NULL;
545 
546 cleanup:
547 	free(node);
548 	if (list)
549 		got_gitconfig_free_list(list);
550 	return err;
551 }
552 
553 /*
554  * Build a list of string values out of the comma separated value denoted by
555  * TAG in SECTION.
556  */
557 struct got_gitconfig_list *
558 got_gitconfig_get_list(struct got_gitconfig *conf, char *section, char *tag)
559 {
560 	char	*liststr = 0, *p, *field, *t;
561 	struct got_gitconfig_list *list = 0;
562 	struct got_gitconfig_list_node *node = 0;
563 
564 	list = malloc(sizeof *list);
565 	if (!list)
566 		goto cleanup;
567 	TAILQ_INIT(&list->fields);
568 	list->cnt = 0;
569 	liststr = got_gitconfig_get_str(conf, section, tag);
570 	if (!liststr)
571 		goto cleanup;
572 	liststr = strdup(liststr);
573 	if (!liststr)
574 		goto cleanup;
575 	p = liststr;
576 	while ((field = strsep(&p, ",")) != NULL) {
577 		/* Skip leading whitespace */
578 		while (isspace((unsigned char)*field))
579 			field++;
580 		/* Skip trailing whitespace */
581 		if (p)
582 			for (t = p - 1; t > field && isspace((unsigned char)*t); t--)
583 				*t = '\0';
584 		if (*field == '\0') {
585 			log_print("got_gitconfig_get_list: empty field, ignoring...");
586 			continue;
587 		}
588 		list->cnt++;
589 		node = calloc(1, sizeof *node);
590 		if (!node)
591 			goto cleanup;
592 		node->field = strdup(field);
593 		if (!node->field)
594 			goto cleanup;
595 		TAILQ_INSERT_TAIL(&list->fields, node, link);
596 	}
597 	free(liststr);
598 	return list;
599 
600 cleanup:
601 	free(node);
602 	if (list)
603 		got_gitconfig_free_list(list);
604 	free(liststr);
605 	return 0;
606 }
607 
608 struct got_gitconfig_list *
609 got_gitconfig_get_tag_list(struct got_gitconfig *conf, const char *section)
610 {
611 	struct got_gitconfig_list *list = 0;
612 	struct got_gitconfig_list_node *node = 0;
613 	struct got_gitconfig_binding *cb;
614 
615 	list = malloc(sizeof *list);
616 	if (!list)
617 		goto cleanup;
618 	TAILQ_INIT(&list->fields);
619 	list->cnt = 0;
620 	for (cb = LIST_FIRST(&conf->bindings[conf_hash(section)]); cb;
621 	    cb = LIST_NEXT(cb, link))
622 		if (strcasecmp(section, cb->section) == 0) {
623 			list->cnt++;
624 			node = calloc(1, sizeof *node);
625 			if (!node)
626 				goto cleanup;
627 			node->field = strdup(cb->tag);
628 			if (!node->field)
629 				goto cleanup;
630 			TAILQ_INSERT_TAIL(&list->fields, node, link);
631 		}
632 	return list;
633 
634 cleanup:
635 	free(node);
636 	if (list)
637 		got_gitconfig_free_list(list);
638 	return 0;
639 }
640 
641 void
642 got_gitconfig_free_list(struct got_gitconfig_list *list)
643 {
644 	struct got_gitconfig_list_node *node = TAILQ_FIRST(&list->fields);
645 
646 	while (node) {
647 		TAILQ_REMOVE(&list->fields, node, link);
648 		free(node->field);
649 		free(node);
650 		node = TAILQ_FIRST(&list->fields);
651 	}
652 	free(list);
653 }
654 
655 static int
656 got_gitconfig_trans_node(struct got_gitconfig *conf, int transaction,
657     enum got_gitconfig_op op, char *section, char *tag, char *value,
658     int override, int is_default)
659 {
660 	struct got_gitconfig_trans *node;
661 
662 	node = calloc(1, sizeof *node);
663 	if (!node) {
664 		log_error("got_gitconfig_trans_node: calloc (1, %lu) failed",
665 		    (unsigned long)sizeof *node);
666 		return 1;
667 	}
668 	node->trans = transaction;
669 	node->op = op;
670 	node->override = override;
671 	node->is_default = is_default;
672 	if (section && (node->section = strdup(section)) == NULL)
673 		goto fail;
674 	if (tag && (node->tag = strdup(tag)) == NULL)
675 		goto fail;
676 	if (value && (node->value = strdup(value)) == NULL)
677 		goto fail;
678 	TAILQ_INSERT_TAIL(&conf->trans_queue, node, link);
679 	return 0;
680 
681 fail:
682 	free(node->section);
683 	free(node->tag);
684 	free(node->value);
685 	free(node);
686 	return 1;
687 }
688 
689 /* Queue a set operation.  */
690 int
691 got_gitconfig_set(struct got_gitconfig *conf, int transaction, char *section,
692     char *tag, char *value, int override, int is_default)
693 {
694 	return got_gitconfig_trans_node(conf, transaction, CONF_SET, section,
695 	    tag, value, override, is_default);
696 }
697 
698 /* Queue a remove operation.  */
699 int
700 got_gitconfig_remove(struct got_gitconfig *conf, int transaction,
701     char *section, char *tag)
702 {
703 	return got_gitconfig_trans_node(conf, transaction, CONF_REMOVE,
704 	    section, tag, NULL, 0, 0);
705 }
706 
707 /* Queue a remove section operation.  */
708 int
709 got_gitconfig_remove_section(struct got_gitconfig *conf, int transaction,
710     char *section)
711 {
712 	return got_gitconfig_trans_node(conf, transaction, CONF_REMOVE_SECTION,
713 	    section, NULL, NULL, 0, 0);
714 }