1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 /*
26  * Copyright (c) 2011 by Delphix. All rights reserved.
27  */
28 /*
29  * Copyright (c) 2013, Joyent, Inc.  All rights reserved.
30  */
31 
32 /*
33  * DTrace print() action
34  *
35  * This file contains the post-processing logic for the print() action.  The
36  * print action behaves identically to trace() in that it generates a
37  * DTRACEACT_DIFEXPR action, but the action argument field refers to a CTF type
38  * string stored in the DOF string table (similar to printf formats).  We
39  * take the result of the trace action and post-process it in the fashion of
40  * MDB's ::print dcmd.
41  *
42  * This implementation differs from MDB's in the following ways:
43  *
44  * 	- We do not expose any options or flags.  The behavior of print() is
45  *	  equivalent to "::print -tn".
46  *
47  * 	- MDB will display "holes" in structures (unused padding between
48  *	  members).
49  *
50  * 	- When printing arrays of structures, MDB will leave a trailing ','
51  *	  after the last element.
52  *
53  *	- MDB will print time_t types as date and time.
54  *
55  *	- MDB will detect when an enum is actually the OR of several flags,
56  *	  and print it out with the constituent flags separated.
57  *
58  *	- For large arrays, MDB will print the first few members and then
59  *	  print a "..." continuation line.
60  *
61  *	- MDB will break and wrap arrays at 80 columns.
62  *
63  *	- MDB prints out floats and doubles by hand, as it must run in kmdb
64  *	  context.  We're able to leverage the printf() format strings,
65  *	  but the result is a slightly different format.
66  */
67 
68 #include <sys/sysmacros.h>
69 #include <strings.h>
70 #include <stdlib.h>
71 #include <alloca.h>
72 #include <assert.h>
73 #include <ctype.h>
74 #include <errno.h>
75 #include <limits.h>
76 #include <sys/socket.h>
77 #include <netdb.h>
78 #include <netinet/in.h>
79 #include <arpa/inet.h>
80 #include <arpa/nameser.h>
81 
82 #include <dt_module.h>
83 #include <dt_printf.h>
84 #include <dt_string.h>
85 #include <dt_impl.h>
86 
87 /* determines whether the given integer CTF encoding is a character */
88 #define	CTF_IS_CHAR(e) \
89 	(((e).cte_format & (CTF_INT_CHAR | CTF_INT_SIGNED)) == \
90 	(CTF_INT_CHAR | CTF_INT_SIGNED) && (e).cte_bits == NBBY)
91 /* determines whether the given CTF kind is a struct or union */
92 #define	CTF_IS_STRUCTLIKE(k) \
93 	((k) == CTF_K_STRUCT || (k) == CTF_K_UNION)
94 
95 /*
96  * Print structure passed down recursively through printing algorithm.
97  */
98 typedef struct dt_printarg {
99 	dtrace_hdl_t	*pa_dtp;	/* libdtrace handle */
100 	caddr_t		pa_addr;	/* base address of trace data */
101 	ctf_file_t	*pa_ctfp;	/* CTF container */
102 	int		pa_depth;	/* member depth */
103 	int		pa_nest;	/* nested array depth */
104 	FILE		*pa_file;	/* output file */
105 } dt_printarg_t;
106 
107 static int dt_print_member(const char *, ctf_id_t, ulong_t, int, void *);
108 
109 /*
110  * Safe version of ctf_type_name() that will fall back to just "<ctfid>" if it
111  * can't resolve the type.
112  */
113 static void
114 dt_print_type_name(ctf_file_t *ctfp, ctf_id_t id, char *buf, size_t buflen)
115 {
116 	if (ctf_type_name(ctfp, id, buf, buflen) == NULL)
117 		(void) snprintf(buf, buflen, "<%ld>", id);
118 }
119 
120 /*
121  * Print any necessary trailing braces for structures or unions.  We don't get
122  * invoked when a struct or union ends, so we infer the need to print braces
123  * based on the depth the last time we printed something and the new depth.
124  */
125 static void
126 dt_print_trailing_braces(dt_printarg_t *pap, int depth)
127 {
128 	int d;
129 
130 	for (d = pap->pa_depth; d > depth; d--) {
131 		(void) fprintf(pap->pa_file, "%*s}%s",
132 		    (d + pap->pa_nest - 1) * 4, "",
133 		    d == depth + 1 ? "" : "\n");
134 	}
135 }
136 
137 /*
138  * Print the appropriate amount of indentation given the current depth and
139  * array nesting.
140  */
141 static void
142 dt_print_indent(dt_printarg_t *pap)
143 {
144 	(void) fprintf(pap->pa_file, "%*s",
145 	    (pap->pa_depth + pap->pa_nest) * 4, "");
146 }
147 
148 /*
149  * Print a bitfield.  It's worth noting that the D compiler support for
150  * bitfields is currently broken; printing "D`user_desc_t" (pulled in by the
151  * various D provider files) will produce incorrect results compared to
152  * "genunix`user_desc_t".
153  */
154 static void
155 print_bitfield(dt_printarg_t *pap, ulong_t off, ctf_encoding_t *ep)
156 {
157 	FILE *fp = pap->pa_file;
158 	caddr_t addr = pap->pa_addr + off / NBBY;
159 	uint64_t mask = (1ULL << ep->cte_bits) - 1;
160 	uint64_t value = 0;
161 	size_t size = (ep->cte_bits + (NBBY - 1)) / NBBY;
162 	uint8_t *buf = (uint8_t *)&value;
163 	uint8_t shift;
164 
165 	/*
166 	 * On big-endian machines, we need to adjust the buf pointer to refer
167 	 * to the lowest 'size' bytes in 'value', and we need to shift based on
168 	 * the offset from the end of the data, not the offset of the start.
169 	 */
170 #ifdef _BIG_ENDIAN
171 	buf += sizeof (value) - size;
172 	off += ep->cte_bits;
173 #endif
174 	bcopy(addr, buf, size);
175 	shift = off % NBBY;
176 
177 	/*
178 	 * Offsets are counted from opposite ends on little- and
179 	 * big-endian machines.
180 	 */
181 #ifdef _BIG_ENDIAN
182 	shift = NBBY - shift;
183 #endif
184 
185 	/*
186 	 * If the bits we want do not begin on a byte boundary, shift the data
187 	 * right so that the value is in the lowest 'cte_bits' of 'value'.
188 	 */
189 	if (off % NBBY != 0)
190 		value >>= shift;
191 	value &= mask;
192 
193 	(void) fprintf(fp, "%#llx", (u_longlong_t)value);
194 }
195 
196 /*
197  * Dump the contents of memory as a fixed-size integer in hex.
198  */
199 static void
200 dt_print_hex(FILE *fp, caddr_t addr, size_t size)
201 {
202 	switch (size) {
203 	case sizeof (uint8_t):
204 		(void) fprintf(fp, "%#x", *(uint8_t *)addr);
205 		break;
206 	case sizeof (uint16_t):
207 		/* LINTED - alignment */
208 		(void) fprintf(fp, "%#x", *(uint16_t *)addr);
209 		break;
210 	case sizeof (uint32_t):
211 		/* LINTED - alignment */
212 		(void) fprintf(fp, "%#x", *(uint32_t *)addr);
213 		break;
214 	case sizeof (uint64_t):
215 		(void) fprintf(fp, "%#llx",
216 		    /* LINTED - alignment */
217 		    (unsigned long long)*(uint64_t *)addr);
218 		break;
219 	default:
220 		(void) fprintf(fp, "<invalid size %u>", (uint_t)size);
221 	}
222 }
223 
224 /*
225  * Print an integer type.  Before dumping the contents via dt_print_hex(), we
226  * first check the encoding to see if it's part of a bitfield or a character.
227  */
228 static void
229 dt_print_int(ctf_id_t base, ulong_t off, dt_printarg_t *pap)
230 {
231 	FILE *fp = pap->pa_file;
232 	ctf_file_t *ctfp = pap->pa_ctfp;
233 	ctf_encoding_t e;
234 	size_t size;
235 	caddr_t addr = pap->pa_addr + off / NBBY;
236 
237 	if (ctf_type_encoding(ctfp, base, &e) == CTF_ERR) {
238 		(void) fprintf(fp, "<unknown encoding>");
239 		return;
240 	}
241 
242 	/*
243 	 * This comes from MDB - it's not clear under what circumstances this
244 	 * would be found.
245 	 */
246 	if (e.cte_format & CTF_INT_VARARGS) {
247 		(void) fprintf(fp, "...");
248 		return;
249 	}
250 
251 	/*
252 	 * We print this as a bitfield if the bit encoding indicates it's not
253 	 * an even power of two byte size, or is larger than 8 bytes.
254 	 */
255 	size = e.cte_bits / NBBY;
256 	if (size > 8 || (e.cte_bits % NBBY) != 0 || (size & (size - 1)) != 0) {
257 		print_bitfield(pap, off, &e);
258 		return;
259 	}
260 
261 	/*
262 	 * If this is a character, print it out as such.
263 	 */
264 	if (CTF_IS_CHAR(e)) {
265 		char c = *(char *)addr;
266 		if (isprint(c))
267 			(void) fprintf(fp, "'%c'", c);
268 		else if (c == 0)
269 			(void) fprintf(fp, "'\\0'");
270 		else
271 			(void) fprintf(fp, "'\\%03o'", c);
272 		return;
273 	}
274 
275 	dt_print_hex(fp, addr, size);
276 }
277 
278 /*
279  * Print a floating point (float, double, long double) value.
280  */
281 /* ARGSUSED */
282 static void
283 dt_print_float(ctf_id_t base, ulong_t off, dt_printarg_t *pap)
284 {
285 	FILE *fp = pap->pa_file;
286 	ctf_file_t *ctfp = pap->pa_ctfp;
287 	ctf_encoding_t e;
288 	caddr_t addr = pap->pa_addr + off / NBBY;
289 
290 	if (ctf_type_encoding(ctfp, base, &e) == 0) {
291 		if (e.cte_format == CTF_FP_SINGLE &&
292 		    e.cte_bits == sizeof (float) * NBBY) {
293 			/* LINTED - alignment */
294 			(void) fprintf(fp, "%+.7e", *((float *)addr));
295 		} else if (e.cte_format == CTF_FP_DOUBLE &&
296 		    e.cte_bits == sizeof (double) * NBBY) {
297 			/* LINTED - alignment */
298 			(void) fprintf(fp, "%+.7e", *((double *)addr));
299 		} else if (e.cte_format == CTF_FP_LDOUBLE &&
300 		    e.cte_bits == sizeof (long double) * NBBY) {
301 			/* LINTED - alignment */
302 			(void) fprintf(fp, "%+.16LE", *((long double *)addr));
303 		} else {
304 			(void) fprintf(fp, "<unknown encoding>");
305 		}
306 	}
307 }
308 
309 /*
310  * A pointer is generally printed as a fixed-size integer.  If we have a
311  * function pointer, we try to look up its name.
312  */
313 static void
314 dt_print_ptr(ctf_id_t base, ulong_t off, dt_printarg_t *pap)
315 {
316 	FILE *fp = pap->pa_file;
317 	ctf_file_t *ctfp = pap->pa_ctfp;
318 	caddr_t addr = pap->pa_addr + off / NBBY;
319 	size_t size = ctf_type_size(ctfp, base);
320 	ctf_id_t bid = ctf_type_reference(ctfp, base);
321 	uint64_t pc;
322 	dtrace_syminfo_t dts;
323 	GElf_Sym sym;
324 
325 	if (bid == CTF_ERR || ctf_type_kind(ctfp, bid) != CTF_K_FUNCTION) {
326 		dt_print_hex(fp, addr, size);
327 	} else {
328 		/* LINTED - alignment */
329 		pc = *((uint64_t *)addr);
330 		if (dtrace_lookup_by_addr(pap->pa_dtp, pc, &sym, &dts) != 0) {
331 			dt_print_hex(fp, addr, size);
332 		} else {
333 			(void) fprintf(fp, "%s`%s", dts.dts_object,
334 			    dts.dts_name);
335 		}
336 	}
337 }
338 
339 /*
340  * Print out an array.  This is somewhat complex, as we must manually visit
341  * each member, and recursively invoke ctf_type_visit() for each member.  If
342  * the members are non-structs, then we print them out directly:
343  *
344  * 	[ 0x14, 0x2e, 0 ]
345  *
346  * If they are structs, then we print out the necessary leading and trailing
347  * braces, to end up with:
348  *
349  *	[
350  *	    type {
351  *	    ...
352  *	    },
353  *	    type {
354  *	    ...
355  *	    }
356  *	]
357  *
358  * We also use a heuristic to detect whether the array looks like a character
359  * array.  If the encoding indicates it's a character, and we have all
360  * printable characters followed by a null byte, then we display it as a
361  * string:
362  *
363  *	[ "string" ]
364  */
365 static void
366 dt_print_array(ctf_id_t base, ulong_t off, dt_printarg_t *pap)
367 {
368 	FILE *fp = pap->pa_file;
369 	ctf_file_t *ctfp = pap->pa_ctfp;
370 	caddr_t addr = pap->pa_addr + off / NBBY;
371 	ctf_arinfo_t car;
372 	ssize_t eltsize;
373 	ctf_encoding_t e;
374 	int i;
375 	boolean_t isstring;
376 	int kind;
377 	ctf_id_t rtype;
378 
379 	if (ctf_array_info(ctfp, base, &car) == CTF_ERR) {
380 		(void) fprintf(fp, "0x%p", (void *)addr);
381 		return;
382 	}
383 
384 	if ((eltsize = ctf_type_size(ctfp, car.ctr_contents)) < 0 ||
385 	    (rtype = ctf_type_resolve(ctfp, car.ctr_contents)) == CTF_ERR ||
386 	    (kind = ctf_type_kind(ctfp, rtype)) == CTF_ERR) {
387 		(void) fprintf(fp, "<invalid type %lu>", car.ctr_contents);
388 		return;
389 	}
390 
391 	/* see if this looks like a string */
392 	isstring = B_FALSE;
393 	if (kind == CTF_K_INTEGER &&
394 	    ctf_type_encoding(ctfp, rtype, &e) != CTF_ERR && CTF_IS_CHAR(e)) {
395 		char c;
396 		for (i = 0; i < car.ctr_nelems; i++) {
397 			c = *((char *)addr + eltsize * i);
398 			if (!isprint(c) || c == '\0')
399 				break;
400 		}
401 
402 		if (i != car.ctr_nelems && c == '\0')
403 			isstring = B_TRUE;
404 	}
405 
406 	/*
407 	 * As a slight aesthetic optimization, if we are a top-level type, then
408 	 * don't bother printing out the brackets.  This lets print("foo") look
409 	 * like:
410 	 *
411 	 * 	string "foo"
412 	 *
413 	 * As D will internally represent this as a char[256] array.
414 	 */
415 	if (!isstring || pap->pa_depth != 0)
416 		(void) fprintf(fp, "[ ");
417 
418 	if (isstring)
419 		(void) fprintf(fp, "\"");
420 
421 	for (i = 0; i < car.ctr_nelems; i++) {
422 		if (isstring) {
423 			char c = *((char *)addr + eltsize * i);
424 			if (c == '\0')
425 				break;
426 			(void) fprintf(fp, "%c", c);
427 		} else {
428 			/*
429 			 * Recursively invoke ctf_type_visit() on each member.
430 			 * We setup a new printarg struct with 'pa_nest' set to
431 			 * indicate that we are within a nested array.
432 			 */
433 			dt_printarg_t pa = *pap;
434 			pa.pa_nest += pap->pa_depth + 1;
435 			pa.pa_depth = 0;
436 			pa.pa_addr = addr + eltsize * i;
437 			(void) ctf_type_visit(ctfp, car.ctr_contents,
438 			    dt_print_member, &pa);
439 
440 			dt_print_trailing_braces(&pa, 0);
441 			if (i != car.ctr_nelems - 1)
442 				(void) fprintf(fp, ", ");
443 			else if (CTF_IS_STRUCTLIKE(kind))
444 				(void) fprintf(fp, "\n");
445 		}
446 	}
447 
448 	if (isstring)
449 		(void) fprintf(fp, "\"");
450 
451 	if (!isstring || pap->pa_depth != 0) {
452 		if (CTF_IS_STRUCTLIKE(kind))
453 			dt_print_indent(pap);
454 		else
455 			(void) fprintf(fp, " ");
456 		(void) fprintf(fp, "]");
457 	}
458 }
459 
460 /*
461  * This isued by both structs and unions to print the leading brace.
462  */
463 /* ARGSUSED */
464 static void
465 dt_print_structlike(ctf_id_t id, ulong_t off, dt_printarg_t *pap)
466 {
467 	(void) fprintf(pap->pa_file, "{");
468 }
469 
470 /*
471  * For enums, we try to print the enum name, and fall back to the value if it
472  * can't be determined.  We do not do any fancy flag processing like mdb.
473  */
474 /* ARGSUSED */
475 static void
476 dt_print_enum(ctf_id_t base, ulong_t off, dt_printarg_t *pap)
477 {
478 	FILE *fp = pap->pa_file;
479 	ctf_file_t *ctfp = pap->pa_ctfp;
480 	const char *ename;
481 	ssize_t size;
482 	caddr_t addr = pap->pa_addr + off / NBBY;
483 	int value = 0;
484 
485 	/*
486 	 * The C standard says that an enum will be at most the sizeof (int).
487 	 * But if all the values are less than that, the compiler can use a
488 	 * smaller size. Thanks standards.
489 	 */
490 	size = ctf_type_size(ctfp, base);
491 	switch (size) {
492 	case sizeof (uint8_t):
493 		value = *(uint8_t *)addr;
494 		break;
495 	case sizeof (uint16_t):
496 		/* LINTED - alignment */
497 		value = *(uint16_t *)addr;
498 		break;
499 	case sizeof (int32_t):
500 		/* LINTED - alignment */
501 		value = *(int32_t *)addr;
502 		break;
503 	default:
504 		(void) fprintf(fp, "<invalid enum size %u>", (uint_t)size);
505 		return;
506 	}
507 
508 	if ((ename = ctf_enum_name(ctfp, base, value)) != NULL)
509 		(void) fprintf(fp, "%s", ename);
510 	else
511 		(void) fprintf(fp, "%d", value);
512 }
513 
514 /*
515  * Forward declaration.  There's not much to do here without the complete
516  * type information, so just print out this fact and drive on.
517  */
518 /* ARGSUSED */
519 static void
520 dt_print_tag(ctf_id_t base, ulong_t off, dt_printarg_t *pap)
521 {
522 	(void) fprintf(pap->pa_file, "<forward decl>");
523 }
524 
525 typedef void dt_printarg_f(ctf_id_t, ulong_t, dt_printarg_t *);
526 
527 static dt_printarg_f *const dt_printfuncs[] = {
528 	dt_print_int,		/* CTF_K_INTEGER */
529 	dt_print_float,		/* CTF_K_FLOAT */
530 	dt_print_ptr,		/* CTF_K_POINTER */
531 	dt_print_array,		/* CTF_K_ARRAY */
532 	dt_print_ptr,		/* CTF_K_FUNCTION */
533 	dt_print_structlike,	/* CTF_K_STRUCT */
534 	dt_print_structlike,	/* CTF_K_UNION */
535 	dt_print_enum,		/* CTF_K_ENUM */
536 	dt_print_tag		/* CTF_K_FORWARD */
537 };
538 
539 /*
540  * Print one member of a structure.  This callback is invoked from
541  * ctf_type_visit() recursively.
542  */
543 static int
544 dt_print_member(const char *name, ctf_id_t id, ulong_t off, int depth,
545     void *data)
546 {
547 	char type[DT_TYPE_NAMELEN];
548 	int kind;
549 	dt_printarg_t *pap = data;
550 	FILE *fp = pap->pa_file;
551 	ctf_file_t *ctfp = pap->pa_ctfp;
552 	boolean_t arraymember;
553 	boolean_t brief;
554 	ctf_encoding_t e;
555 	ctf_id_t rtype;
556 
557 	dt_print_trailing_braces(pap, depth);
558 	/*
559 	 * dt_print_trailing_braces() doesn't include the trailing newline; add
560 	 * it here if necessary.
561 	 */
562 	if (depth < pap->pa_depth)
563 		(void) fprintf(fp, "\n");
564 	pap->pa_depth = depth;
565 
566 	if ((rtype = ctf_type_resolve(ctfp, id)) == CTF_ERR ||
567 	    (kind = ctf_type_kind(ctfp, rtype)) == CTF_ERR ||
568 	    kind < CTF_K_INTEGER || kind > CTF_K_FORWARD) {
569 		dt_print_indent(pap);
570 		(void) fprintf(fp, "%s = <invalid type %lu>", name, id);
571 		return (0);
572 	}
573 
574 	dt_print_type_name(ctfp, id, type, sizeof (type));
575 
576 	arraymember = (pap->pa_nest != 0 && depth == 0);
577 	brief = (arraymember && !CTF_IS_STRUCTLIKE(kind));
578 
579 	if (!brief) {
580 		/*
581 		 * If this is a direct array member and a struct (otherwise
582 		 * brief would be true), then print a trailing newline, as the
583 		 * array printing code doesn't include it because it might be a
584 		 * simple type.
585 		 */
586 		if (arraymember)
587 			(void) fprintf(fp, "\n");
588 		dt_print_indent(pap);
589 
590 		/* always print the type */
591 		(void) fprintf(fp, "%s", type);
592 		if (name[0] != '\0') {
593 			/*
594 			 * For aesthetics, we don't include a space between the
595 			 * type name and member name if the type is a pointer.
596 			 * This will give us "void *foo =" instead of "void *
597 			 * foo =".  Unions also have the odd behavior that the
598 			 * type name is returned as "union ", with a trailing
599 			 * space, so we also avoid printing a space if the type
600 			 * name already ends with a space.
601 			 */
602 			if (type[strlen(type) - 1] != '*' &&
603 			    type[strlen(type) -1] != ' ') {
604 				(void) fprintf(fp, " ");
605 			}
606 			(void) fprintf(fp, "%s", name);
607 
608 			/*
609 			 * If this looks like a bitfield, or is an integer not
610 			 * aligned on a byte boundary, print the number of
611 			 * bits after the name.
612 			 */
613 			if (kind == CTF_K_INTEGER &&
614 			    ctf_type_encoding(ctfp, id, &e) == 0) {
615 				ulong_t bits = e.cte_bits;
616 				ulong_t size = bits / NBBY;
617 
618 				if (bits % NBBY != 0 ||
619 				    off % NBBY != 0 ||
620 				    size > 8 ||
621 				    size != ctf_type_size(ctfp, id)) {
622 					(void) fprintf(fp, " :%lu", bits);
623 				}
624 			}
625 
626 			(void) fprintf(fp, " =");
627 		}
628 		(void) fprintf(fp, " ");
629 	}
630 
631 	dt_printfuncs[kind - 1](rtype, off, pap);
632 
633 	/* direct simple array members are not separated by newlines */
634 	if (!brief)
635 		(void) fprintf(fp, "\n");
636 
637 	return (0);
638 }
639 
640 /*
641  * Main print function invoked by dt_consume_cpu().
642  */
643 int
644 dtrace_print(dtrace_hdl_t *dtp, FILE *fp, const char *typename,
645     caddr_t addr, size_t len)
646 {
647 	const char *s;
648 	char *object;
649 	dt_printarg_t pa;
650 	ctf_id_t id;
651 	dt_module_t *dmp;
652 	ctf_file_t *ctfp;
653 	int libid;
654 
655 	/*
656 	 * Split the fully-qualified type ID (module`id).  This should
657 	 * always be the format, but if for some reason we don't find the
658 	 * expected value, return 0 to fall back to the generic trace()
659 	 * behavior. In the case of userland CTF modules this will actually be
660 	 * of the format (module`lib`id). This is due to the fact that those
661 	 * modules have multiple CTF containers which `lib` identifies.
662 	 */
663 	for (s = typename; *s != '\0' && *s != '`'; s++)
664 		;
665 
666 	if (*s != '`')
667 		return (0);
668 
669 	object = alloca(s - typename + 1);
670 	bcopy(typename, object, s - typename);
671 	object[s - typename] = '\0';
672 	dmp = dt_module_lookup_by_name(dtp, object);
673 	if (dmp == NULL)
674 		return (0);
675 
676 	if (dmp->dm_pid != 0) {
677 		libid = atoi(s + 1);
678 		s = strchr(s + 1, '`');
679 		if (s == NULL || libid > dmp->dm_nctflibs)
680 			return (0);
681 		ctfp = dmp->dm_libctfp[libid];
682 	} else {
683 		ctfp = dt_module_getctf(dtp, dmp);
684 	}
685 
686 	id = atoi(s + 1);
687 
688 	/*
689 	 * Try to get the CTF kind for this id.  If something has gone horribly
690 	 * wrong and we can't resolve the ID, bail out and let trace() do the
691 	 * work.
692 	 */
693 	if (ctfp == NULL || ctf_type_kind(ctfp, id) == CTF_ERR)
694 		return (0);
695 
696 	/* setup the print structure and kick off the main print routine */
697 	pa.pa_dtp = dtp;
698 	pa.pa_addr = addr;
699 	pa.pa_ctfp = ctfp;
700 	pa.pa_nest = 0;
701 	pa.pa_depth = 0;
702 	pa.pa_file = fp;
703 	(void) ctf_type_visit(pa.pa_ctfp, id, dt_print_member, &pa);
704 
705 	dt_print_trailing_braces(&pa, 0);
706 
707 	return (len);
708 }
709