xref: /freebsd/contrib/elftoolchain/addr2line/addr2line.c (revision e8d8bef961a50d4dc22501cde4fb9fb0be1b2532)
1 /*-
2  * Copyright (c) 2009 Kai Wang
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <sys/param.h>
28 #include <sys/tree.h>
29 
30 #include <capsicum_helpers.h>
31 #include <dwarf.h>
32 #include <err.h>
33 #include <fcntl.h>
34 #include <gelf.h>
35 #include <getopt.h>
36 #include <libdwarf.h>
37 #include <libelftc.h>
38 #include <libgen.h>
39 #include <stdbool.h>
40 #include <stdio.h>
41 #include <stdlib.h>
42 #include <string.h>
43 
44 #include "_elftc.h"
45 
46 ELFTC_VCSID("$Id: addr2line.c 3499 2016-11-25 16:06:29Z emaste $");
47 
48 struct Func {
49 	char *name;
50 	Dwarf_Unsigned lopc;
51 	Dwarf_Unsigned hipc;
52 	Dwarf_Unsigned call_file;
53 	Dwarf_Unsigned call_line;
54 	Dwarf_Ranges *ranges;
55 	Dwarf_Signed ranges_cnt;
56 	struct Func *inlined_caller;
57 	STAILQ_ENTRY(Func) next;
58 };
59 
60 struct range {
61 	RB_ENTRY(range) entry;
62 	Dwarf_Off off;
63 	Dwarf_Unsigned lopc;
64 	Dwarf_Unsigned hipc;
65 	char **srcfiles;
66 	Dwarf_Signed nsrcfiles;
67 	STAILQ_HEAD(, Func) funclist;
68 	Dwarf_Die die;
69 	Dwarf_Debug dbg;
70 };
71 
72 static struct option longopts[] = {
73 	{"addresses", no_argument, NULL, 'a'},
74 	{"target" , required_argument, NULL, 'b'},
75 	{"demangle", no_argument, NULL, 'C'},
76 	{"exe", required_argument, NULL, 'e'},
77 	{"functions", no_argument, NULL, 'f'},
78 	{"inlines", no_argument, NULL, 'i'},
79 	{"section", required_argument, NULL, 'j'},
80 	{"pretty-print", no_argument, NULL, 'p'},
81 	{"basename", no_argument, NULL, 's'},
82 	{"help", no_argument, NULL, 'H'},
83 	{"version", no_argument, NULL, 'V'},
84 	{NULL, 0, NULL, 0}
85 };
86 
87 static int demangle, func, base, inlines, print_addr, pretty_print;
88 static char unknown[] = { '?', '?', '\0' };
89 static Dwarf_Addr section_base;
90 /* Need a new curlopc that stores last lopc value. */
91 static Dwarf_Unsigned curlopc = ~0ULL;
92 static RB_HEAD(cutree, range) cuhead = RB_INITIALIZER(&cuhead);
93 
94 static int
95 lopccmp(struct range *e1, struct range *e2)
96 {
97 	return (e1->lopc < e2->lopc ? -1 : e1->lopc > e2->lopc);
98 }
99 
100 RB_PROTOTYPE(cutree, range, entry, lopccmp);
101 RB_GENERATE(cutree, range, entry, lopccmp)
102 
103 #define	USAGE_MESSAGE	"\
104 Usage: %s [options] hexaddress...\n\
105   Map program addresses to source file names and line numbers.\n\n\
106   Options:\n\
107   -a      | --addresses       Display address prior to line number info.\n\
108   -b TGT  | --target=TGT      (Accepted but ignored).\n\
109   -e EXE  | --exe=EXE         Use program \"EXE\" to translate addresses.\n\
110   -f      | --functions       Display function names.\n\
111   -i      | --inlines         Display caller info for inlined functions.\n\
112   -j NAME | --section=NAME    Values are offsets into section \"NAME\".\n\
113   -p      | --pretty-print    Display line number info and function name\n\
114                               in human readable manner.\n\
115   -s      | --basename        Only show the base name for each file name.\n\
116   -C      | --demangle        Demangle C++ names.\n\
117   -H      | --help            Print a help message.\n\
118   -V      | --version         Print a version identifier and exit.\n"
119 
120 static void
121 usage(void)
122 {
123 	(void) fprintf(stderr, USAGE_MESSAGE, ELFTC_GETPROGNAME());
124 	exit(1);
125 }
126 
127 static void
128 version(void)
129 {
130 
131 	fprintf(stderr, "%s (%s)\n", ELFTC_GETPROGNAME(), elftc_version());
132 	exit(0);
133 }
134 
135 /*
136  * Handle DWARF 4 'offset from' DW_AT_high_pc.  Although we don't
137  * fully support DWARF 4, some compilers (like FreeBSD Clang 3.5.1)
138  * generate DW_AT_high_pc as an offset from DW_AT_low_pc.
139  *
140  * "If the value of the DW_AT_high_pc is of class address, it is the
141  * relocated address of the first location past the last instruction
142  * associated with the entity; if it is of class constant, the value
143  * is an unsigned integer offset which when added to the low PC gives
144  * the address of the first location past the last instruction
145  * associated with the entity."
146  *
147  * DWARF4 spec, section 2.17.2.
148  */
149 static int
150 handle_high_pc(Dwarf_Die die, Dwarf_Unsigned lopc, Dwarf_Unsigned *hipc)
151 {
152 	Dwarf_Error de;
153 	Dwarf_Half form;
154 	Dwarf_Attribute at;
155 	int ret;
156 
157 	ret = dwarf_attr(die, DW_AT_high_pc, &at, &de);
158 	if (ret == DW_DLV_ERROR) {
159 		warnx("dwarf_attr failed: %s", dwarf_errmsg(de));
160 		return (ret);
161 	}
162 	ret = dwarf_whatform(at, &form, &de);
163 	if (ret == DW_DLV_ERROR) {
164 		warnx("dwarf_whatform failed: %s", dwarf_errmsg(de));
165 		return (ret);
166 	}
167 	if (dwarf_get_form_class(2, 0, 0, form) == DW_FORM_CLASS_CONSTANT)
168 		*hipc += lopc;
169 
170 	return (DW_DLV_OK);
171 }
172 
173 static struct Func *
174 search_func(struct range *range, Dwarf_Unsigned addr)
175 {
176 	struct Func *f, *f0;
177 	Dwarf_Unsigned lopc, hipc, addr_base;
178 	int i;
179 
180 	f0 = NULL;
181 
182 	STAILQ_FOREACH(f, &range->funclist, next) {
183 		if (f->ranges != NULL) {
184 			addr_base = 0;
185 			for (i = 0; i < f->ranges_cnt; i++) {
186 				if (f->ranges[i].dwr_type == DW_RANGES_END)
187 					break;
188 				if (f->ranges[i].dwr_type ==
189 				    DW_RANGES_ADDRESS_SELECTION) {
190 					addr_base = f->ranges[i].dwr_addr2;
191 					continue;
192 				}
193 
194 				/* DW_RANGES_ENTRY */
195 				lopc = f->ranges[i].dwr_addr1 + addr_base;
196 				hipc = f->ranges[i].dwr_addr2 + addr_base;
197 				if (addr >= lopc && addr < hipc) {
198 					if (f0 == NULL ||
199 					    (lopc >= f0->lopc &&
200 					    hipc <= f0->hipc)) {
201 						f0 = f;
202 						f0->lopc = lopc;
203 						f0->hipc = hipc;
204 						break;
205 					}
206 				}
207 			}
208 		} else if (addr >= f->lopc && addr < f->hipc) {
209 			if (f0 == NULL ||
210 			    (f->lopc >= f0->lopc && f->hipc <= f0->hipc))
211 				f0 = f;
212 		}
213 	}
214 
215 	return (f0);
216 }
217 
218 static void
219 collect_func(Dwarf_Debug dbg, Dwarf_Die die, struct Func *parent,
220     struct range *range)
221 {
222 	Dwarf_Die ret_die, abst_die, spec_die;
223 	Dwarf_Error de;
224 	Dwarf_Half tag;
225 	Dwarf_Unsigned lopc, hipc, ranges_off;
226 	Dwarf_Signed ranges_cnt;
227 	Dwarf_Off ref;
228 	Dwarf_Attribute abst_at, spec_at;
229 	Dwarf_Ranges *ranges;
230 	const char *funcname;
231 	struct Func *f;
232 	int found_ranges, ret;
233 
234 	f = NULL;
235 	abst_die = spec_die = NULL;
236 
237 	if (dwarf_tag(die, &tag, &de)) {
238 		warnx("dwarf_tag: %s", dwarf_errmsg(de));
239 		goto cont_search;
240 	}
241 	if (tag == DW_TAG_subprogram || tag == DW_TAG_entry_point ||
242 	    tag == DW_TAG_inlined_subroutine || tag == DW_TAG_label) {
243 		/*
244 		 * Function address range can be specified by either
245 		 * a DW_AT_ranges attribute which points to a range list or
246 		 * by a pair of DW_AT_low_pc and DW_AT_high_pc attributes.
247 		 */
248 		ranges = NULL;
249 		ranges_cnt = 0;
250 		found_ranges = 0;
251 		if (dwarf_attrval_unsigned(die, DW_AT_ranges, &ranges_off,
252 		    &de) == DW_DLV_OK &&
253 		    dwarf_get_ranges(dbg, (Dwarf_Off) ranges_off, &ranges,
254 		    &ranges_cnt, NULL, &de) == DW_DLV_OK) {
255 			if (ranges != NULL && ranges_cnt > 0) {
256 				found_ranges = 1;
257 				goto get_func_name;
258 			}
259 		}
260 
261 		/*
262 		 * Ranges pointer not found.  Search for DW_AT_low_pc, and
263 		 * DW_AT_high_pc iff die is not a label.  Labels doesn't have
264 		 * hipc attr. */
265 		if (tag == DW_TAG_label) {
266 			if (dwarf_attrval_unsigned(die, DW_AT_low_pc, &lopc,
267 			    &de) != DW_DLV_OK)
268 				goto cont_search;
269 		} else {
270 			if (dwarf_attrval_unsigned(die, DW_AT_low_pc, &lopc,
271 			    &de) || dwarf_attrval_unsigned(die, DW_AT_high_pc,
272 			    &hipc, &de))
273 				goto cont_search;
274 			if (handle_high_pc(die, lopc, &hipc) != DW_DLV_OK)
275 				goto cont_search;
276 		}
277 
278 	get_func_name:
279 		/*
280 		 * Most common case the function name is stored in DW_AT_name
281 		 * attribute.
282 		 */
283 		if (dwarf_attrval_string(die, DW_AT_name, &funcname, &de) ==
284 		    DW_DLV_OK)
285 			goto add_func;
286 
287 		/*
288 		 * For inlined function, the actual name is probably in the DIE
289 		 * referenced by DW_AT_abstract_origin. (if present)
290 		 */
291 		if (dwarf_attr(die, DW_AT_abstract_origin, &abst_at, &de) ==
292 		    DW_DLV_OK &&
293 		    dwarf_global_formref(abst_at, &ref, &de) == DW_DLV_OK &&
294 		    dwarf_offdie(dbg, ref, &abst_die, &de) == DW_DLV_OK &&
295 		    dwarf_attrval_string(abst_die, DW_AT_name, &funcname,
296 		    &de) == DW_DLV_OK)
297 			goto add_func;
298 
299 		/*
300 		 * If DW_AT_name is not present, but DW_AT_specification is
301 		 * present, then probably the actual name is in the DIE
302 		 * referenced by DW_AT_specification.
303 		 */
304 		if (dwarf_attr(die, DW_AT_specification, &spec_at, &de) ==
305 		    DW_DLV_OK &&
306 		    dwarf_global_formref(spec_at, &ref, &de) == DW_DLV_OK &&
307 		    dwarf_offdie(dbg, ref, &spec_die, &de) == DW_DLV_OK &&
308 		    dwarf_attrval_string(spec_die, DW_AT_name, &funcname,
309 		    &de) == DW_DLV_OK)
310 			goto add_func;
311 
312 		/* Skip if no name associated with this DIE. */
313 		goto cont_search;
314 
315 	add_func:
316 		if ((f = calloc(1, sizeof(*f))) == NULL)
317 			err(EXIT_FAILURE, "calloc");
318 		if ((f->name = strdup(funcname)) == NULL)
319 			err(EXIT_FAILURE, "strdup");
320 		if (found_ranges) {
321 			f->ranges = ranges;
322 			f->ranges_cnt = ranges_cnt;
323 		} else {
324 			f->lopc = lopc;
325 			f->hipc = hipc;
326 		}
327 		if (tag == DW_TAG_inlined_subroutine) {
328 			f->inlined_caller = parent;
329 			dwarf_attrval_unsigned(die, DW_AT_call_file,
330 			    &f->call_file, &de);
331 			dwarf_attrval_unsigned(die, DW_AT_call_line,
332 			    &f->call_line, &de);
333 		}
334 		STAILQ_INSERT_TAIL(&range->funclist, f, next);
335 	}
336 
337 cont_search:
338 
339 	/* Search children. */
340 	ret = dwarf_child(die, &ret_die, &de);
341 	if (ret == DW_DLV_ERROR)
342 		warnx("dwarf_child: %s", dwarf_errmsg(de));
343 	else if (ret == DW_DLV_OK) {
344 		if (f != NULL)
345 			collect_func(dbg, ret_die, f, range);
346 		else
347 			collect_func(dbg, ret_die, parent, range);
348 	}
349 
350 	/* Search sibling. */
351 	ret = dwarf_siblingof(dbg, die, &ret_die, &de);
352 	if (ret == DW_DLV_ERROR)
353 		warnx("dwarf_siblingof: %s", dwarf_errmsg(de));
354 	else if (ret == DW_DLV_OK)
355 		collect_func(dbg, ret_die, parent, range);
356 
357 	/* Cleanup */
358 	if (die != range->die)
359 		dwarf_dealloc(dbg, die, DW_DLA_DIE);
360 
361 	if (abst_die != NULL)
362 		dwarf_dealloc(dbg, abst_die, DW_DLA_DIE);
363 
364 	if (spec_die != NULL)
365 		dwarf_dealloc(dbg, spec_die, DW_DLA_DIE);
366 }
367 
368 static void
369 print_inlines(struct range *range, struct Func *f, Dwarf_Unsigned call_file,
370     Dwarf_Unsigned call_line)
371 {
372 	char demangled[1024];
373 	char *file;
374 
375 	if (call_file > 0 && (Dwarf_Signed) call_file <= range->nsrcfiles)
376 		file = range->srcfiles[call_file - 1];
377 	else
378 		file = unknown;
379 
380 	if (pretty_print)
381 		printf(" (inlined by) ");
382 
383 	if (func) {
384 		if (demangle && !elftc_demangle(f->name, demangled,
385 		    sizeof(demangled), 0)) {
386 			if (pretty_print)
387 				printf("%s at ", demangled);
388 			else
389 				printf("%s\n", demangled);
390 		} else {
391 			if (pretty_print)
392 				printf("%s at ", f->name);
393 			else
394 				printf("%s\n", f->name);
395 		}
396 	}
397 	(void) printf("%s:%ju\n", base ? basename(file) : file,
398 	    (uintmax_t) call_line);
399 
400 	if (f->inlined_caller != NULL)
401 		print_inlines(range, f->inlined_caller, f->call_file,
402 		    f->call_line);
403 }
404 
405 static struct range *
406 culookup(Dwarf_Unsigned addr)
407 {
408 	struct range find, *res;
409 
410 	find.lopc = addr;
411 	res = RB_NFIND(cutree, &cuhead, &find);
412 	if (res != NULL) {
413 		if (res->lopc != addr)
414 			res = RB_PREV(cutree, &cuhead, res);
415 		if (res != NULL && addr >= res->lopc && addr < res->hipc)
416 			return (res);
417 	} else {
418 		res = RB_MAX(cutree, &cuhead);
419 		if (res != NULL && addr >= res->lopc && addr < res->hipc)
420 			return (res);
421 	}
422 	return (NULL);
423 }
424 
425 /*
426  * When DW_AT_ranges, DW_AT_low_pc/DW_AT_high_pc are all absent, we check the
427  * children of cu die for labels.  If the address falls into one of the labels
428  * ranges(aranges), return the label DIE.
429  */
430 static int
431 check_labels(Dwarf_Debug dbg, Dwarf_Die die, Dwarf_Unsigned addr,
432     struct range **range) {
433 	Dwarf_Addr start;
434 	Dwarf_Arange *aranges;
435 	Dwarf_Die prev_die, ret_die;
436 	Dwarf_Error de;
437 	Dwarf_Half tag;
438 	Dwarf_Off die_off;
439 	Dwarf_Unsigned lopc, length;
440 	Dwarf_Signed arcnt;
441 	struct range *labelp, **labels;
442 	int i, j, label_cnt, ret;
443 
444 	prev_die = ret_die = NULL;
445 	labels = NULL;
446 	i = label_cnt = 0;
447 
448 	/* Find aranges. */
449 	ret = dwarf_get_aranges(dbg, &aranges, &arcnt, &de);
450 	if (ret != DW_DLV_OK && ret != DW_DLV_NO_ENTRY)
451 		warnx("dwarf_get_aranges failed: %s", dwarf_errmsg(de));
452 
453 	/* Child of current CU. */
454 	ret = dwarf_child(die, &prev_die, &de);
455 	if (ret == DW_DLV_ERROR)
456 		warnx("dwarf_child: %s", dwarf_errmsg(de));
457 
458 	/* Count labels. */
459 	while (1) {
460 		if (dwarf_tag(prev_die, &tag, &de) != DW_DLV_OK) {
461 			warnx("dwarf_tag failed: %s",
462 				dwarf_errmsg(de));
463 			return DW_DLV_ERROR;
464 		}
465 		if (tag == DW_TAG_label) {
466 			if (dwarf_attrval_unsigned(prev_die, DW_AT_low_pc,
467 			    &lopc, &de) == DW_DLV_OK)
468 				label_cnt++;
469 		}
470 
471 		if (dwarf_siblingof(dbg, prev_die, &ret_die, &de) != DW_DLV_OK)
472 			break;
473 
474 		if (prev_die != NULL)
475 			dwarf_dealloc(dbg, prev_die, DW_DLA_DIE);
476 		prev_die = ret_die;
477 	}
478 
479 	if (label_cnt == 0)
480 		return (DW_DLV_NO_ENTRY);
481 
482 	/* Allocate space for labels. */
483 	if ((labels = calloc(label_cnt, sizeof(struct range *))) == NULL)
484 		err(EXIT_FAILURE, "calloc");
485 
486 	/* Add labels to list. */
487 	ret = dwarf_child(die, &prev_die, &de);
488 	if (ret == DW_DLV_ERROR)
489 		warnx("dwarf_child: %s", dwarf_errmsg(de));
490 	while (1) {
491 		if (dwarf_tag(prev_die, &tag, &de) != DW_DLV_OK) {
492 			warnx("dwarf_tag failed: %s",
493 				dwarf_errmsg(de));
494 			free(labels);
495 			return DW_DLV_ERROR;
496 		}
497 		if (tag == DW_TAG_label) {
498 			if (dwarf_attrval_unsigned(prev_die, DW_AT_low_pc,
499 			    &lopc, &de) == DW_DLV_OK) {
500 				if (curlopc == lopc) {
501 					for (i = 0; i < label_cnt - 1; i++) {
502 						if (labels[i] != *range)
503 							free(labels[i]);
504 					}
505 					free(labels);
506 					return DW_DLV_ERROR;
507 				}
508 				labelp = calloc(1, sizeof(struct range));
509 				if (labelp == NULL)
510 					err(EXIT_FAILURE, "calloc");
511 				labelp->lopc = lopc;
512 				labelp->die = prev_die;
513 				labelp->dbg = dbg;
514 				STAILQ_INIT(&labelp->funclist);
515 				labels[i++] = labelp;
516 			}
517 		}
518 		if (dwarf_siblingof(dbg, prev_die, &ret_die, &de) != DW_DLV_OK)
519 			break;
520 		if (prev_die != NULL && tag != DW_TAG_label)
521 			dwarf_dealloc(dbg, prev_die, DW_DLA_DIE);
522 		prev_die = ret_die;
523 	}
524 
525 	/* Set hipc for each label using aranges */
526 	for (i = 0; i < label_cnt; i++) {
527 		for (j = 0; j < arcnt; j++) {
528 			if (dwarf_get_arange_info(aranges[j], &start, &length,
529 			    &die_off, &de) != DW_DLV_OK) {
530 				warnx("dwarf_get_arange_info failed: %s",
531 					dwarf_errmsg(de));
532 				continue;
533 			}
534 			if (labels[i]->lopc == (Dwarf_Unsigned)start) {
535 				labels[i]->hipc = start + length;
536 				break;
537 			}
538 		}
539 	}
540 
541 	/* If addr in label's range, we have found the range for this label. */
542 	for (i = 0; i < label_cnt; i++) {
543 		if (addr >= labels[i]->lopc && addr < labels[i]->hipc) {
544 			*range = labels[i];
545 			RB_INSERT(cutree, &cuhead, (*range));
546 			curlopc = (*range)->lopc;
547 			break;
548 		}
549 	}
550 
551 	for (i = 0; i < label_cnt - 1; i++) {
552 		if (labels[i] != *range)
553 			free(labels[i]);
554 	}
555 	free(labels);
556 
557 	if (*range != NULL)
558 		return (DW_DLV_OK);
559 	else
560 		return (DW_DLV_NO_ENTRY);
561 }
562 
563 /*
564  * Check whether addr falls into range(s) of current CU.
565  * If so, save current CU to lookup tree.
566  */
567 static int
568 check_range(Dwarf_Debug dbg, Dwarf_Die die, Dwarf_Unsigned addr,
569     struct range **range)
570 {
571 	Dwarf_Error de;
572 	Dwarf_Unsigned addr_base, lopc, hipc;
573 	Dwarf_Off ranges_off;
574 	Dwarf_Signed ranges_cnt;
575 	Dwarf_Ranges *ranges;
576 	int i, ret;
577 	bool in_cu;
578 
579 	addr_base = 0;
580 	ranges = NULL;
581 	ranges_cnt = 0;
582 	in_cu = false;
583 
584 	if (dwarf_attrval_unsigned(die, DW_AT_ranges, &ranges_off, &de) ==
585 	    DW_DLV_OK) {
586 		ret = dwarf_get_ranges(dbg, ranges_off, &ranges,
587 			&ranges_cnt, NULL, &de);
588 		if (ret != DW_DLV_OK)
589 			return (ret);
590 
591 		if (!ranges || ranges_cnt <= 0)
592 			return (DW_DLV_ERROR);
593 
594 		for (i = 0; i < ranges_cnt; i++) {
595 			if (ranges[i].dwr_type == DW_RANGES_END)
596 				return (DW_DLV_NO_ENTRY);
597 
598 			if (ranges[i].dwr_type ==
599 				DW_RANGES_ADDRESS_SELECTION) {
600 				addr_base = ranges[i].dwr_addr2;
601 				continue;
602 			}
603 
604 			/* DW_RANGES_ENTRY */
605 			lopc = ranges[i].dwr_addr1 + addr_base;
606 			hipc = ranges[i].dwr_addr2 + addr_base;
607 
608 			if (lopc == curlopc)
609 				return (DW_DLV_ERROR);
610 
611 			if (addr >= lopc && addr < hipc){
612 				in_cu = true;
613 				break;
614 			}
615 		}
616 	} else if (dwarf_attrval_unsigned(die, DW_AT_low_pc, &lopc, &de) ==
617 	    DW_DLV_OK) {
618 		if (lopc == curlopc)
619 			return (DW_DLV_ERROR);
620 		if (dwarf_attrval_unsigned(die, DW_AT_high_pc, &hipc, &de) ==
621 		    DW_DLV_OK) {
622 			/*
623 			 * Check if the address falls into the PC
624 			 * range of this CU.
625 			 */
626 			if (handle_high_pc(die, lopc, &hipc) != DW_DLV_OK)
627 				return (DW_DLV_ERROR);
628 		} else {
629 			/* Assume ~0ULL if DW_AT_high_pc not present. */
630 			hipc = ~0ULL;
631 		}
632 
633 		if (addr >= lopc && addr < hipc) {
634 			in_cu = true;
635 		}
636 	} else {
637 		/* Addr not found above, try labels. */
638 		ret = check_labels(dbg, die, addr, range);
639 		return ret;
640 	}
641 
642 	if (in_cu) {
643 		if ((*range = calloc(1, sizeof(struct range))) == NULL)
644 			err(EXIT_FAILURE, "calloc");
645 		(*range)->lopc = lopc;
646 		(*range)->hipc = hipc;
647 		(*range)->die = die;
648 		(*range)->dbg = dbg;
649 		STAILQ_INIT(&(*range)->funclist);
650 		RB_INSERT(cutree, &cuhead, *range);
651 		curlopc = lopc;
652 		return (DW_DLV_OK);
653 	} else {
654 		return (DW_DLV_NO_ENTRY);
655 	}
656 }
657 
658 static void
659 translate(Dwarf_Debug dbg, Elf *e, const char* addrstr)
660 {
661 	Dwarf_Die die, ret_die;
662 	Dwarf_Line *lbuf;
663 	Dwarf_Error de;
664 	Dwarf_Half tag;
665 	Dwarf_Unsigned addr, lineno, plineno;
666 	Dwarf_Signed lcount;
667 	Dwarf_Addr lineaddr, plineaddr;
668 	struct range *range;
669 	struct Func *f;
670 	const char *funcname;
671 	char *file, *file0, *pfile;
672 	char demangled[1024];
673 	int ec, i, ret;
674 
675 	addr = strtoull(addrstr, NULL, 16);
676 	addr += section_base;
677 	lineno = 0;
678 	file = unknown;
679 	die = NULL;
680 	ret = DW_DLV_OK;
681 
682 	range = culookup(addr);
683 	if (range != NULL) {
684 		die = range->die;
685 		dbg = range->dbg;
686 		goto status_ok;
687 	}
688 
689 	while (true) {
690 		/*
691 		 * We resume the CU scan from the last place we found a match.
692 		 * Because when we have 2 sequential addresses, and the second
693 		 * one is of the next CU, it is faster to just go to the next CU
694 		 * instead of starting from the beginning.
695 		 */
696 		ret = dwarf_next_cu_header(dbg, NULL, NULL, NULL, NULL, NULL,
697 		    &de);
698 		if (ret == DW_DLV_NO_ENTRY) {
699 			if (curlopc == ~0ULL)
700 				goto out;
701 			ret = dwarf_next_cu_header(dbg, NULL, NULL, NULL, NULL,
702 			    NULL, &de);
703 		}
704 		die = NULL;
705 		while (dwarf_siblingof(dbg, die, &ret_die, &de) == DW_DLV_OK) {
706 			if (die != NULL)
707 				dwarf_dealloc(dbg, die, DW_DLA_DIE);
708 			die = ret_die;
709 			if (dwarf_tag(die, &tag, &de) != DW_DLV_OK) {
710 				warnx("dwarf_tag failed: %s",
711 				    dwarf_errmsg(de));
712 				goto next_cu;
713 			}
714 
715 			/* XXX: What about DW_TAG_partial_unit? */
716 			if (tag == DW_TAG_compile_unit)
717 				break;
718 		}
719 
720 		if (ret_die == NULL) {
721 			warnx("could not find DW_TAG_compile_unit die");
722 			goto next_cu;
723 		}
724 		ret = check_range(dbg, die, addr, &range);
725 		if (ret == DW_DLV_OK)
726 			break;
727 		if (ret == DW_DLV_ERROR)
728 			goto out;
729 next_cu:
730 		if (die != NULL) {
731 			dwarf_dealloc(dbg, die, DW_DLA_DIE);
732 			die = NULL;
733 		}
734 	}
735 
736 	if (ret != DW_DLV_OK || die == NULL)
737 		goto out;
738 
739 status_ok:
740 	switch (dwarf_srclines(die, &lbuf, &lcount, &de)) {
741 	case DW_DLV_OK:
742 		break;
743 	case DW_DLV_NO_ENTRY:
744 		/* If a CU lacks debug info, just skip it. */
745 		goto out;
746 	default:
747 		warnx("dwarf_srclines: %s", dwarf_errmsg(de));
748 		goto out;
749 	}
750 
751 	plineaddr = ~0ULL;
752 	plineno = 0;
753 	pfile = unknown;
754 	for (i = 0; i < lcount; i++) {
755 		if (dwarf_lineaddr(lbuf[i], &lineaddr, &de)) {
756 			warnx("dwarf_lineaddr: %s", dwarf_errmsg(de));
757 			goto out;
758 		}
759 		if (dwarf_lineno(lbuf[i], &lineno, &de)) {
760 			warnx("dwarf_lineno: %s", dwarf_errmsg(de));
761 			goto out;
762 		}
763 		if (dwarf_linesrc(lbuf[i], &file0, &de)) {
764 			warnx("dwarf_linesrc: %s", dwarf_errmsg(de));
765 		} else
766 			file = file0;
767 		if (addr == lineaddr)
768 			goto out;
769 		else if (addr < lineaddr && addr > plineaddr) {
770 			lineno = plineno;
771 			file = pfile;
772 			goto out;
773 		}
774 		plineaddr = lineaddr;
775 		plineno = lineno;
776 		pfile = file;
777 	}
778 
779 out:
780 	f = NULL;
781 	funcname = NULL;
782 	if (ret == DW_DLV_OK && (func || inlines) && range != NULL) {
783 		if (range->srcfiles == NULL)
784 			if (dwarf_srcfiles(die, &range->srcfiles,
785 			    &range->nsrcfiles, &de))
786 				warnx("dwarf_srcfiles: %s", dwarf_errmsg(de));
787 		if (STAILQ_EMPTY(&range->funclist)) {
788 			collect_func(dbg, range->die, NULL, range);
789 			die = NULL;
790 		}
791 		f = search_func(range, addr);
792 		if (f != NULL)
793 			funcname = f->name;
794 	}
795 
796 	if (print_addr) {
797 		if ((ec = gelf_getclass(e)) == ELFCLASSNONE) {
798 			warnx("gelf_getclass failed: %s", elf_errmsg(-1));
799 			ec = ELFCLASS64;
800 		}
801 		if (ec == ELFCLASS32) {
802 			if (pretty_print)
803 				printf("0x%08jx: ", (uintmax_t) addr);
804 			else
805 				printf("0x%08jx\n", (uintmax_t) addr);
806 		} else {
807 			if (pretty_print)
808 				printf("0x%016jx: ", (uintmax_t) addr);
809 			else
810 				printf("0x%016jx\n", (uintmax_t) addr);
811 		}
812 	}
813 
814 	if (func) {
815 		if (funcname == NULL)
816 			funcname = unknown;
817 		if (demangle && !elftc_demangle(funcname, demangled,
818 		    sizeof(demangled), 0)) {
819 			if (pretty_print)
820 				printf("%s at ", demangled);
821 			else
822 				printf("%s\n", demangled);
823 		} else {
824 			if (pretty_print)
825 				printf("%s at ", funcname);
826 			else
827 				printf("%s\n", funcname);
828 		}
829 	}
830 
831 	(void) printf("%s:%ju\n", base ? basename(file) : file,
832 	    (uintmax_t) lineno);
833 
834 	if (ret == DW_DLV_OK && inlines && range != NULL &&
835 	    range->srcfiles != NULL && f != NULL && f->inlined_caller != NULL)
836 		print_inlines(range, f->inlined_caller, f->call_file,
837 		    f->call_line);
838 }
839 
840 static void
841 find_section_base(const char *exe, Elf *e, const char *section)
842 {
843 	Dwarf_Addr off;
844 	Elf_Scn *scn;
845 	GElf_Ehdr eh;
846 	GElf_Shdr sh;
847 	size_t shstrndx;
848 	int elferr;
849 	const char *name;
850 
851 	if (gelf_getehdr(e, &eh) != &eh) {
852 		warnx("gelf_getehdr failed: %s", elf_errmsg(-1));
853 		return;
854 	}
855 
856 	if (!elf_getshstrndx(e, &shstrndx)) {
857 		warnx("elf_getshstrndx failed: %s", elf_errmsg(-1));
858 		return;
859 	}
860 
861 	(void) elf_errno();
862 	off = 0;
863 	scn = NULL;
864 	while ((scn = elf_nextscn(e, scn)) != NULL) {
865 		if (gelf_getshdr(scn, &sh) == NULL) {
866 			warnx("gelf_getshdr failed: %s", elf_errmsg(-1));
867 			continue;
868 		}
869 		if ((name = elf_strptr(e, shstrndx, sh.sh_name)) == NULL)
870 			goto next;
871 		if (!strcmp(section, name)) {
872 			if (eh.e_type == ET_EXEC || eh.e_type == ET_DYN) {
873 				/*
874 				 * For executables, section base is the virtual
875 				 * address of the specified section.
876 				 */
877 				section_base = sh.sh_addr;
878 			} else if (eh.e_type == ET_REL) {
879 				/*
880 				 * For relocatables, section base is the
881 				 * relative offset of the specified section
882 				 * to the start of the first section.
883 				 */
884 				section_base = off;
885 			} else
886 				warnx("unknown e_type %u", eh.e_type);
887 			return;
888 		}
889 	next:
890 		off += sh.sh_size;
891 	}
892 	elferr = elf_errno();
893 	if (elferr != 0)
894 		warnx("elf_nextscn failed: %s", elf_errmsg(elferr));
895 
896 	errx(EXIT_FAILURE, "%s: cannot find section %s", exe, section);
897 }
898 
899 int
900 main(int argc, char **argv)
901 {
902 	cap_rights_t rights;
903 	Elf *e;
904 	Dwarf_Debug dbg;
905 	Dwarf_Error de;
906 	const char *exe, *section;
907 	char line[1024];
908 	int fd, i, opt;
909 
910 	exe = NULL;
911 	section = NULL;
912 	while ((opt = getopt_long(argc, argv, "ab:Ce:fij:psHV", longopts,
913 	    NULL)) != -1) {
914 		switch (opt) {
915 		case 'a':
916 			print_addr = 1;
917 			break;
918 		case 'b':
919 			/* ignored */
920 			break;
921 		case 'C':
922 			demangle = 1;
923 			break;
924 		case 'e':
925 			exe = optarg;
926 			break;
927 		case 'f':
928 			func = 1;
929 			break;
930 		case 'i':
931 			inlines = 1;
932 			break;
933 		case 'j':
934 			section = optarg;
935 			break;
936 		case 'p':
937 			pretty_print = 1;
938 			break;
939 		case 's':
940 			base = 1;
941 			break;
942 		case 'H':
943 			usage();
944 		case 'V':
945 			version();
946 		default:
947 			usage();
948 		}
949 	}
950 
951 	argv += optind;
952 	argc -= optind;
953 
954 	if (exe == NULL)
955 		exe = "a.out";
956 
957 	if ((fd = open(exe, O_RDONLY)) < 0)
958 		err(EXIT_FAILURE, "%s", exe);
959 
960 	if (caph_rights_limit(fd, cap_rights_init(&rights, CAP_FSTAT,
961 	    CAP_MMAP_R)) < 0)
962 		errx(EXIT_FAILURE, "caph_rights_limit");
963 
964 	caph_cache_catpages();
965 	if (caph_limit_stdio() < 0)
966 		errx(EXIT_FAILURE, "failed to limit stdio rights");
967 	if (caph_enter() < 0)
968 		errx(EXIT_FAILURE, "failed to enter capability mode");
969 
970 	if (dwarf_init(fd, DW_DLC_READ, NULL, NULL, &dbg, &de))
971 		errx(EXIT_FAILURE, "dwarf_init: %s", dwarf_errmsg(de));
972 
973 	if (dwarf_get_elf(dbg, &e, &de) != DW_DLV_OK)
974 		errx(EXIT_FAILURE, "dwarf_get_elf: %s", dwarf_errmsg(de));
975 
976 	if (section)
977 		find_section_base(exe, e, section);
978 	else
979 		section_base = 0;
980 
981 	if (argc > 0)
982 		for (i = 0; i < argc; i++)
983 			translate(dbg, e, argv[i]);
984 	else {
985 		setvbuf(stdout, NULL, _IOLBF, 0);
986 		while (fgets(line, sizeof(line), stdin) != NULL)
987 			translate(dbg, e, line);
988 	}
989 
990 	dwarf_finish(dbg, &de);
991 
992 	(void) elf_end(e);
993 
994 	exit(0);
995 }
996