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 (c) 2012, Joyent, Inc. All rights reserved.
23 */
24
25 /*
26 * mdb(1M) module for debugging the V8 JavaScript engine. This implementation
27 * makes heavy use of metadata defined in the V8 binary for inspecting in-memory
28 * structures. Canned configurations can be manually loaded for V8 binaries
29 * that predate this metadata. See mdb_v8_cfg.c for details.
30 */
31
32 #include <sys/mdb_modapi.h>
33 #include <assert.h>
34 #include <ctype.h>
35 #include <stdarg.h>
36 #include <stdio.h>
37 #include <string.h>
38 #include <libproc.h>
39 #include <sys/avl.h>
40
41 #include "v8dbg.h"
42 #include "v8cfg.h"
43
44 #define offsetof(s, m) ((size_t)(&(((s *)0)->m)))
45
46 /*
47 * The "v8_class" and "v8_field" structures describe the C++ classes used to
48 * represent V8 heap objects.
49 */
50 typedef struct v8_class {
51 struct v8_class *v8c_next; /* list linkage */
52 struct v8_class *v8c_parent; /* parent class (inheritance) */
53 struct v8_field *v8c_fields; /* array of class fields */
54 size_t v8c_start; /* offset of first class field */
55 size_t v8c_end; /* offset of first subclass field */
56 char v8c_name[64]; /* heap object class name */
57 } v8_class_t;
58
59 typedef struct v8_field {
60 struct v8_field *v8f_next; /* list linkage */
61 ssize_t v8f_offset; /* field offset */
62 char v8f_name[64]; /* field name */
63 boolean_t v8f_isbyte; /* 1-byte int field */
64 } v8_field_t;
65
66 /*
67 * Similarly, the "v8_enum" structure describes an enum from V8.
68 */
69 typedef struct {
70 char v8e_name[64];
71 uint_t v8e_value;
72 } v8_enum_t;
73
74 /*
75 * During configuration, the dmod updates these globals with the actual set of
76 * classes, types, and frame types based on the debug metadata.
77 */
78 static v8_class_t *v8_classes;
79
80 static v8_enum_t v8_types[128];
81 static int v8_next_type;
82
83 static v8_enum_t v8_frametypes[16];
84 static int v8_next_frametype;
85
86 static int v8_silent;
87
88 /*
89 * The following constants describe offsets from the frame pointer that are used
90 * to inspect each stack frame. They're initialized from the debug metadata.
91 */
92 static ssize_t V8_OFF_FP_CONTEXT;
93 static ssize_t V8_OFF_FP_MARKER;
94 static ssize_t V8_OFF_FP_FUNCTION;
95 static ssize_t V8_OFF_FP_ARGS;
96
97 /*
98 * The following constants are used by macros defined in heap-dbg-common.h to
99 * examine the types of various V8 heap objects. In general, the macros should
100 * be preferred to using the constants directly. The values of these constants
101 * are initialized from the debug metadata.
102 */
103 static intptr_t V8_FirstNonstringType;
104 static intptr_t V8_IsNotStringMask;
105 static intptr_t V8_StringTag;
106 static intptr_t V8_NotStringTag;
107 static intptr_t V8_StringEncodingMask;
108 static intptr_t V8_TwoByteStringTag;
109 static intptr_t V8_AsciiStringTag;
110 static intptr_t V8_StringRepresentationMask;
111 static intptr_t V8_SeqStringTag;
112 static intptr_t V8_ConsStringTag;
113 static intptr_t V8_ExternalStringTag;
114 static intptr_t V8_FailureTag;
115 static intptr_t V8_FailureTagMask;
116 static intptr_t V8_HeapObjectTag;
117 static intptr_t V8_HeapObjectTagMask;
118 static intptr_t V8_SmiTag;
119 static intptr_t V8_SmiTagMask;
120 static intptr_t V8_SmiValueShift;
121 static intptr_t V8_PointerSizeLog2;
122
123 static intptr_t V8_PROP_IDX_CONTENT;
124 static intptr_t V8_PROP_IDX_FIRST;
125 static intptr_t V8_PROP_TYPE_FIELD;
126 static intptr_t V8_PROP_FIRST_PHANTOM;
127 static intptr_t V8_PROP_TYPE_MASK;
128 static intptr_t V8_PROP_DESC_KEY;
129 static intptr_t V8_PROP_DESC_DETAILS;
130 static intptr_t V8_PROP_DESC_VALUE;
131 static intptr_t V8_PROP_DESC_SIZE;
132 static intptr_t V8_TRANSITIONS_IDX_DESC;
133
134 static intptr_t V8_TYPE_JSOBJECT = -1;
135 static intptr_t V8_TYPE_FIXEDARRAY = -1;
136
137 /*
138 * Although we have this information in v8_classes, the following offsets are
139 * defined explicitly because they're used directly in code below.
140 */
141 static ssize_t V8_OFF_CODE_INSTRUCTION_SIZE;
142 static ssize_t V8_OFF_CODE_INSTRUCTION_START;
143 static ssize_t V8_OFF_CONSSTRING_FIRST;
144 static ssize_t V8_OFF_CONSSTRING_SECOND;
145 static ssize_t V8_OFF_EXTERNALSTRING_RESOURCE;
146 static ssize_t V8_OFF_FIXEDARRAY_DATA;
147 static ssize_t V8_OFF_FIXEDARRAY_LENGTH;
148 static ssize_t V8_OFF_HEAPNUMBER_VALUE;
149 static ssize_t V8_OFF_HEAPOBJECT_MAP;
150 static ssize_t V8_OFF_JSFUNCTION_SHARED;
151 static ssize_t V8_OFF_JSOBJECT_ELEMENTS;
152 static ssize_t V8_OFF_JSOBJECT_PROPERTIES;
153 static ssize_t V8_OFF_MAP_CONSTRUCTOR;
154 static ssize_t V8_OFF_MAP_INOBJECT_PROPERTIES;
155 static ssize_t V8_OFF_MAP_INSTANCE_ATTRIBUTES;
156 static ssize_t V8_OFF_MAP_INSTANCE_DESCRIPTORS;
157 static ssize_t V8_OFF_MAP_INSTANCE_SIZE;
158 static ssize_t V8_OFF_MAP_TRANSITIONS;
159 static ssize_t V8_OFF_ODDBALL_TO_STRING;
160 static ssize_t V8_OFF_SCRIPT_LINE_ENDS;
161 static ssize_t V8_OFF_SCRIPT_NAME;
162 static ssize_t V8_OFF_SEQASCIISTR_CHARS;
163 static ssize_t V8_OFF_SHAREDFUNCTIONINFO_CODE;
164 static ssize_t V8_OFF_SHAREDFUNCTIONINFO_FUNCTION_TOKEN_POSITION;
165 static ssize_t V8_OFF_SHAREDFUNCTIONINFO_INFERRED_NAME;
166 static ssize_t V8_OFF_SHAREDFUNCTIONINFO_LENGTH;
167 static ssize_t V8_OFF_SHAREDFUNCTIONINFO_SCRIPT;
168 static ssize_t V8_OFF_SHAREDFUNCTIONINFO_NAME;
169 static ssize_t V8_OFF_STRING_LENGTH;
170
171 #define NODE_OFF_EXTSTR_DATA 0x4 /* see node_string.h */
172
173 /*
174 * Table of constants used directly by this file.
175 */
176 typedef struct v8_constant {
177 intptr_t *v8c_valp;
178 const char *v8c_symbol;
179 } v8_constant_t;
180
181 static v8_constant_t v8_constants[] = {
182 { &V8_OFF_FP_CONTEXT, "v8dbg_off_fp_context" },
183 { &V8_OFF_FP_FUNCTION, "v8dbg_off_fp_function" },
184 { &V8_OFF_FP_MARKER, "v8dbg_off_fp_marker" },
185 { &V8_OFF_FP_ARGS, "v8dbg_off_fp_args" },
186
187 { &V8_FirstNonstringType, "v8dbg_FirstNonstringType" },
188 { &V8_IsNotStringMask, "v8dbg_IsNotStringMask" },
189 { &V8_StringTag, "v8dbg_StringTag" },
190 { &V8_NotStringTag, "v8dbg_NotStringTag" },
191 { &V8_StringEncodingMask, "v8dbg_StringEncodingMask" },
192 { &V8_TwoByteStringTag, "v8dbg_TwoByteStringTag" },
193 { &V8_AsciiStringTag, "v8dbg_AsciiStringTag" },
194 { &V8_StringRepresentationMask, "v8dbg_StringRepresentationMask" },
195 { &V8_SeqStringTag, "v8dbg_SeqStringTag" },
196 { &V8_ConsStringTag, "v8dbg_ConsStringTag" },
197 { &V8_ExternalStringTag, "v8dbg_ExternalStringTag" },
198 { &V8_FailureTag, "v8dbg_FailureTag" },
199 { &V8_FailureTagMask, "v8dbg_FailureTagMask" },
200 { &V8_HeapObjectTag, "v8dbg_HeapObjectTag" },
201 { &V8_HeapObjectTagMask, "v8dbg_HeapObjectTagMask" },
202 { &V8_SmiTag, "v8dbg_SmiTag" },
203 { &V8_SmiTagMask, "v8dbg_SmiTagMask" },
204 { &V8_SmiValueShift, "v8dbg_SmiValueShift" },
205 { &V8_PointerSizeLog2, "v8dbg_PointerSizeLog2" },
206
207 { &V8_PROP_IDX_FIRST, "v8dbg_prop_idx_first" },
208 { &V8_PROP_TYPE_FIELD, "v8dbg_prop_type_field" },
209 { &V8_PROP_FIRST_PHANTOM, "v8dbg_prop_type_first_phantom" },
210 { &V8_PROP_TYPE_MASK, "v8dbg_prop_type_mask" },
211 };
212
213 static int v8_nconstants = sizeof (v8_constants) / sizeof (v8_constants[0]);
214
215 /*
216 * Some constants are -- for a variety of reasons -- optional.
217 */
218 static v8_constant_t v8_optionals[] = {
219 { &V8_PROP_IDX_CONTENT, "v8dbg_prop_idx_content" },
220 { &V8_PROP_DESC_KEY, "v8dbg_prop_desc_key" },
221 { &V8_PROP_DESC_DETAILS, "v8dbg_prop_desc_details" },
222 { &V8_PROP_DESC_VALUE, "v8dbg_prop_desc_value" },
223 { &V8_PROP_DESC_SIZE, "v8dbg_prop_desc_size" },
224 { &V8_TRANSITIONS_IDX_DESC, "v8dbg_transitions_idx_descriptors" }
225 };
226
227 static int v8_noptionals = sizeof (v8_optionals) / sizeof (v8_optionals[0]);
228
229 typedef struct v8_offset {
230 ssize_t *v8o_valp;
231 const char *v8o_class;
232 const char *v8o_member;
233 boolean_t v8o_optional;
234 } v8_offset_t;
235
236 static v8_offset_t v8_offsets[] = {
237 { &V8_OFF_CODE_INSTRUCTION_SIZE,
238 "Code", "instruction_size" },
239 { &V8_OFF_CODE_INSTRUCTION_START,
240 "Code", "instruction_start" },
241 { &V8_OFF_CONSSTRING_FIRST,
242 "ConsString", "first" },
243 { &V8_OFF_CONSSTRING_SECOND,
244 "ConsString", "second" },
245 { &V8_OFF_EXTERNALSTRING_RESOURCE,
246 "ExternalString", "resource" },
247 { &V8_OFF_FIXEDARRAY_DATA,
248 "FixedArray", "data" },
249 { &V8_OFF_FIXEDARRAY_LENGTH,
250 "FixedArray", "length" },
251 { &V8_OFF_HEAPNUMBER_VALUE,
252 "HeapNumber", "value" },
253 { &V8_OFF_HEAPOBJECT_MAP,
254 "HeapObject", "map" },
255 { &V8_OFF_JSFUNCTION_SHARED,
256 "JSFunction", "shared" },
257 { &V8_OFF_JSOBJECT_ELEMENTS,
258 "JSObject", "elements" },
259 { &V8_OFF_JSOBJECT_PROPERTIES,
260 "JSObject", "properties" },
261 { &V8_OFF_MAP_CONSTRUCTOR,
262 "Map", "constructor" },
263 { &V8_OFF_MAP_INOBJECT_PROPERTIES,
264 "Map", "inobject_properties" },
265 { &V8_OFF_MAP_INSTANCE_ATTRIBUTES,
266 "Map", "instance_attributes" },
267 { &V8_OFF_MAP_INSTANCE_DESCRIPTORS,
268 "Map", "instance_descriptors", B_TRUE },
269 { &V8_OFF_MAP_TRANSITIONS,
270 "Map", "transitions", B_TRUE },
271 { &V8_OFF_MAP_INSTANCE_SIZE,
272 "Map", "instance_size" },
273 { &V8_OFF_ODDBALL_TO_STRING,
274 "Oddball", "to_string" },
275 { &V8_OFF_SCRIPT_LINE_ENDS,
276 "Script", "line_ends" },
277 { &V8_OFF_SCRIPT_NAME,
278 "Script", "name" },
279 { &V8_OFF_SEQASCIISTR_CHARS,
280 "SeqAsciiString", "chars" },
281 { &V8_OFF_SHAREDFUNCTIONINFO_CODE,
282 "SharedFunctionInfo", "code" },
283 { &V8_OFF_SHAREDFUNCTIONINFO_FUNCTION_TOKEN_POSITION,
284 "SharedFunctionInfo", "function_token_position" },
285 { &V8_OFF_SHAREDFUNCTIONINFO_INFERRED_NAME,
286 "SharedFunctionInfo", "inferred_name" },
287 { &V8_OFF_SHAREDFUNCTIONINFO_LENGTH,
288 "SharedFunctionInfo", "length" },
289 { &V8_OFF_SHAREDFUNCTIONINFO_NAME,
290 "SharedFunctionInfo", "name" },
291 { &V8_OFF_SHAREDFUNCTIONINFO_SCRIPT,
292 "SharedFunctionInfo", "script" },
293 { &V8_OFF_STRING_LENGTH,
294 "String", "length" },
295 };
296
297 static int v8_noffsets = sizeof (v8_offsets) / sizeof (v8_offsets[0]);
298
299 static int autoconf_iter_symbol(mdb_symbol_t *, void *);
300 static v8_class_t *conf_class_findcreate(const char *);
301 static v8_field_t *conf_field_create(v8_class_t *, const char *, size_t);
302 static char *conf_next_part(char *, char *);
303 static int conf_update_parent(const char *);
304 static int conf_update_field(v8_cfg_t *, const char *);
305 static int conf_update_enum(v8_cfg_t *, const char *, const char *,
306 v8_enum_t *);
307 static int conf_update_type(v8_cfg_t *, const char *);
308 static int conf_update_frametype(v8_cfg_t *, const char *);
309 static void conf_class_compute_offsets(v8_class_t *);
310
311 static int read_typebyte(uint8_t *, uintptr_t);
312 static int heap_offset(const char *, const char *, ssize_t *);
313
314 /*
315 * Invoked when this dmod is initially loaded to load the set of classes, enums,
316 * and other constants from the metadata in the target binary.
317 */
318 static int
319 autoconfigure(v8_cfg_t *cfgp)
320 {
321 v8_class_t *clp;
322 v8_enum_t *ep;
323 struct v8_constant *cnp;
324 int ii;
325 int failed = 0;
326
327 assert(v8_classes == NULL);
328
329 /*
330 * Iterate all global symbols looking for metadata.
331 */
332 if (cfgp->v8cfg_iter(cfgp, autoconf_iter_symbol, cfgp) != 0) {
333 mdb_warn("failed to autoconfigure V8 support\n");
334 return (-1);
335 }
336
337 /*
338 * By now we've configured all of the classes so we can update the
339 * "start" and "end" fields in each class with information from its
340 * parent class.
341 */
342 for (clp = v8_classes; clp != NULL; clp = clp->v8c_next) {
343 if (clp->v8c_end != (size_t)-1)
344 continue;
345
346 conf_class_compute_offsets(clp);
347 };
348
349 /*
350 * Load various constants used directly in the module.
351 */
352 for (ii = 0; ii < v8_nconstants; ii++) {
353 cnp = &v8_constants[ii];
354
355 if (cfgp->v8cfg_readsym(cfgp, cnp->v8c_symbol,
356 cnp->v8c_valp) == -1) {
357 mdb_warn("failed to read \"%s\"", cnp->v8c_symbol);
358 failed++;
359 }
360 }
361
362 /*
363 * Load optional constants; if we fail to load an optional constant,
364 * we'll set its value to be -1.
365 */
366 for (ii = 0; ii < v8_noptionals; ii++) {
367 cnp = &v8_optionals[ii];
368
369 if (cfgp->v8cfg_readsym(cfgp, cnp->v8c_symbol,
370 cnp->v8c_valp) == -1) {
371 *cnp->v8c_valp = -1;
372 }
373 }
374
375 /*
376 * We need to do some cleanup here: there are versions of node (in
377 * particular, early v0.8 releases) in which v8dbg_prop_idx_content had
378 * been removed but the descriptor variables had not yet been added;
379 * we'll fill those in now with what we know those values to be.
380 */
381 if (V8_PROP_IDX_CONTENT == -1 && V8_PROP_DESC_SIZE == -1) {
382 V8_PROP_DESC_KEY = 0;
383 V8_PROP_DESC_DETAILS = 1;
384 V8_PROP_DESC_VALUE = 2;
385 V8_PROP_DESC_SIZE = 3;
386 }
387
388 /*
389 * Load type values for well-known classes that we use a lot.
390 */
391 for (ep = v8_types; ep->v8e_name[0] != '\0'; ep++) {
392 if (strcmp(ep->v8e_name, "JSObject") == 0)
393 V8_TYPE_JSOBJECT = ep->v8e_value;
394
395 if (strcmp(ep->v8e_name, "FixedArray") == 0)
396 V8_TYPE_FIXEDARRAY = ep->v8e_value;
397 }
398
399 if (V8_TYPE_JSOBJECT == -1 || V8_TYPE_FIXEDARRAY == -1) {
400 mdb_warn("couldn't find %s type\n",
401 V8_TYPE_JSOBJECT == -1 ? "JSObject" : "FixedArray");
402 failed++;
403 }
404
405 /*
406 * Finally, load various class offsets.
407 */
408 for (ii = 0; ii < v8_noffsets; ii++) {
409 struct v8_offset *offp = &v8_offsets[ii];
410 const char *klass = offp->v8o_class;
411
412 again:
413 if (heap_offset(klass, offp->v8o_member, offp->v8o_valp) == 0)
414 continue;
415
416 if (strcmp(klass, "FixedArray") == 0) {
417 /*
418 * The V8 included in node v0.6 uses a FixedArrayBase
419 * class to contain the "length" field, while the one
420 * in v0.4 has no such base class and stores the field
421 * directly in FixedArray; if we failed to derive
422 * the offset from FixedArray, try FixedArrayBase.
423 */
424 klass = "FixedArrayBase";
425 goto again;
426 }
427
428 if (offp->v8o_optional) {
429 *offp->v8o_valp = -1;
430 continue;
431 }
432
433 mdb_warn("couldn't find class \"%s\", field \"%s\"\n",
434 offp->v8o_class, offp->v8o_member);
435 failed++;
436 }
437
438 return (failed ? -1 : 0);
439 }
440
441 /* ARGSUSED */
442 static int
443 autoconf_iter_symbol(mdb_symbol_t *symp, void *arg)
444 {
445 v8_cfg_t *cfgp = arg;
446
447 if (strncmp(symp->sym_name, "v8dbg_parent_",
448 sizeof ("v8dbg_parent_") - 1) == 0)
449 return (conf_update_parent(symp->sym_name));
450
451 if (strncmp(symp->sym_name, "v8dbg_class_",
452 sizeof ("v8dbg_class_") - 1) == 0)
453 return (conf_update_field(cfgp, symp->sym_name));
454
455 if (strncmp(symp->sym_name, "v8dbg_type_",
456 sizeof ("v8dbg_type_") - 1) == 0)
457 return (conf_update_type(cfgp, symp->sym_name));
458
459 if (strncmp(symp->sym_name, "v8dbg_frametype_",
460 sizeof ("v8dbg_frametype_") - 1) == 0)
461 return (conf_update_frametype(cfgp, symp->sym_name));
462
463 return (0);
464 }
465
466 /*
467 * Extracts the next field of a string whose fields are separated by "__" (as
468 * the V8 metadata symbols are).
469 */
470 static char *
471 conf_next_part(char *buf, char *start)
472 {
473 char *pp;
474
475 if ((pp = strstr(start, "__")) == NULL) {
476 mdb_warn("malformed symbol name: %s\n", buf);
477 return (NULL);
478 }
479
480 *pp = '\0';
481 return (pp + sizeof ("__") - 1);
482 }
483
484 static v8_class_t *
485 conf_class_findcreate(const char *name)
486 {
487 v8_class_t *clp, *iclp, *prev = NULL;
488 int cmp;
489
490 for (iclp = v8_classes; iclp != NULL; iclp = iclp->v8c_next) {
491 if ((cmp = strcmp(iclp->v8c_name, name)) == 0)
492 return (iclp);
493
494 if (cmp > 0)
495 break;
496
497 prev = iclp;
498 }
499
500 if ((clp = mdb_zalloc(sizeof (*clp), UM_NOSLEEP)) == NULL)
501 return (NULL);
502
503 (void) strlcpy(clp->v8c_name, name, sizeof (clp->v8c_name));
504 clp->v8c_end = (size_t)-1;
505 clp->v8c_next = iclp;
506
507 if (prev != NULL) {
508 prev->v8c_next = clp;
509 } else {
510 v8_classes = clp;
511 }
512
513 return (clp);
514 }
515
516 static v8_field_t *
517 conf_field_create(v8_class_t *clp, const char *name, size_t offset)
518 {
519 v8_field_t *flp, *iflp;
520
521 if ((flp = mdb_zalloc(sizeof (*flp), UM_NOSLEEP)) == NULL)
522 return (NULL);
523
524 (void) strlcpy(flp->v8f_name, name, sizeof (flp->v8f_name));
525 flp->v8f_offset = offset;
526
527 if (clp->v8c_fields == NULL || clp->v8c_fields->v8f_offset > offset) {
528 flp->v8f_next = clp->v8c_fields;
529 clp->v8c_fields = flp;
530 return (flp);
531 }
532
533 for (iflp = clp->v8c_fields; iflp->v8f_next != NULL;
534 iflp = iflp->v8f_next) {
535 if (iflp->v8f_next->v8f_offset > offset)
536 break;
537 }
538
539 flp->v8f_next = iflp->v8f_next;
540 iflp->v8f_next = flp;
541 return (flp);
542 }
543
544 /*
545 * Given a "v8dbg_parent_X__Y", symbol, update the parent of class X to class Y.
546 * Note that neither class necessarily exists already.
547 */
548 static int
549 conf_update_parent(const char *symbol)
550 {
551 char *pp, *qq;
552 char buf[128];
553 v8_class_t *clp, *pclp;
554
555 (void) strlcpy(buf, symbol, sizeof (buf));
556 pp = buf + sizeof ("v8dbg_parent_") - 1;
557 qq = conf_next_part(buf, pp);
558
559 if (qq == NULL)
560 return (-1);
561
562 clp = conf_class_findcreate(pp);
563 pclp = conf_class_findcreate(qq);
564
565 if (clp == NULL || pclp == NULL) {
566 mdb_warn("mdb_v8: out of memory\n");
567 return (-1);
568 }
569
570 clp->v8c_parent = pclp;
571 return (0);
572 }
573
574 /*
575 * Given a "v8dbg_class_CLASS__FIELD__TYPE", symbol, save field "FIELD" into
576 * class CLASS with the offset described by the symbol. Note that CLASS does
577 * not necessarily exist already.
578 */
579 static int
580 conf_update_field(v8_cfg_t *cfgp, const char *symbol)
581 {
582 v8_class_t *clp;
583 v8_field_t *flp;
584 intptr_t offset;
585 char *pp, *qq, *tt;
586 char buf[128];
587
588 (void) strlcpy(buf, symbol, sizeof (buf));
589
590 pp = buf + sizeof ("v8dbg_class_") - 1;
591 qq = conf_next_part(buf, pp);
592
593 if (qq == NULL || (tt = conf_next_part(buf, qq)) == NULL)
594 return (-1);
595
596 if (cfgp->v8cfg_readsym(cfgp, symbol, &offset) == -1) {
597 mdb_warn("failed to read symbol \"%s\"", symbol);
598 return (-1);
599 }
600
601 if ((clp = conf_class_findcreate(pp)) == NULL ||
602 (flp = conf_field_create(clp, qq, (size_t)offset)) == NULL)
603 return (-1);
604
605 if (strcmp(tt, "int") == 0)
606 flp->v8f_isbyte = B_TRUE;
607
608 return (0);
609 }
610
611 static int
612 conf_update_enum(v8_cfg_t *cfgp, const char *symbol, const char *name,
613 v8_enum_t *enp)
614 {
615 intptr_t value;
616
617 if (cfgp->v8cfg_readsym(cfgp, symbol, &value) == -1) {
618 mdb_warn("failed to read symbol \"%s\"", symbol);
619 return (-1);
620 }
621
622 enp->v8e_value = (int)value;
623 (void) strlcpy(enp->v8e_name, name, sizeof (enp->v8e_name));
624 return (0);
625 }
626
627 /*
628 * Given a "v8dbg_type_TYPENAME" constant, save the type name in v8_types. Note
629 * that this enum has multiple integer values with the same string label.
630 */
631 static int
632 conf_update_type(v8_cfg_t *cfgp, const char *symbol)
633 {
634 char *klass;
635 v8_enum_t *enp;
636 char buf[128];
637
638 if (v8_next_type > sizeof (v8_types) / sizeof (v8_types[0])) {
639 mdb_warn("too many V8 types\n");
640 return (-1);
641 }
642
643 (void) strlcpy(buf, symbol, sizeof (buf));
644
645 klass = buf + sizeof ("v8dbg_type_") - 1;
646 if (conf_next_part(buf, klass) == NULL)
647 return (-1);
648
649 enp = &v8_types[v8_next_type++];
650 return (conf_update_enum(cfgp, symbol, klass, enp));
651 }
652
653 /*
654 * Given a "v8dbg_frametype_TYPENAME" constant, save the frame type in
655 * v8_frametypes.
656 */
657 static int
658 conf_update_frametype(v8_cfg_t *cfgp, const char *symbol)
659 {
660 const char *frametype;
661 v8_enum_t *enp;
662
663 if (v8_next_frametype >
664 sizeof (v8_frametypes) / sizeof (v8_frametypes[0])) {
665 mdb_warn("too many V8 frame types\n");
666 return (-1);
667 }
668
669 enp = &v8_frametypes[v8_next_frametype++];
670 frametype = symbol + sizeof ("v8dbg_frametype_") - 1;
671 return (conf_update_enum(cfgp, symbol, frametype, enp));
672 }
673
674 /*
675 * Now that all classes have been loaded, update the "start" and "end" fields of
676 * each class based on the values of its parent class.
677 */
678 static void
679 conf_class_compute_offsets(v8_class_t *clp)
680 {
681 v8_field_t *flp;
682
683 assert(clp->v8c_start == 0);
684 assert(clp->v8c_end == (size_t)-1);
685
686 if (clp->v8c_parent != NULL) {
687 if (clp->v8c_parent->v8c_end == (size_t)-1)
688 conf_class_compute_offsets(clp->v8c_parent);
689
690 clp->v8c_start = clp->v8c_parent->v8c_end;
691 }
692
693 if (clp->v8c_fields == NULL) {
694 clp->v8c_end = clp->v8c_start;
695 return;
696 }
697
698 for (flp = clp->v8c_fields; flp->v8f_next != NULL; flp = flp->v8f_next)
699 ;
700
701 if (flp == NULL)
702 clp->v8c_end = clp->v8c_start;
703 else
704 clp->v8c_end = flp->v8f_offset + sizeof (uintptr_t);
705 }
706
707 /*
708 * Utility functions
709 */
710 static int jsstr_print(uintptr_t, boolean_t, char **, size_t *);
711
712 static const char *
713 enum_lookup_str(v8_enum_t *enums, int val, const char *dflt)
714 {
715 v8_enum_t *ep;
716
717 for (ep = enums; ep->v8e_name[0] != '\0'; ep++) {
718 if (ep->v8e_value == val)
719 return (ep->v8e_name);
720 }
721
722 return (dflt);
723 }
724
725 static void
726 enum_print(v8_enum_t *enums)
727 {
728 v8_enum_t *itp;
729
730 for (itp = enums; itp->v8e_name[0] != '\0'; itp++)
731 mdb_printf("%-30s = 0x%02x\n", itp->v8e_name, itp->v8e_value);
732 }
733
734 /*
735 * b[v]snprintf behave like [v]snprintf(3c), except that they update the buffer
736 * and length arguments based on how much buffer space is used by the operation.
737 * This makes it much easier to combine multiple calls in sequence without
738 * worrying about buffer overflow.
739 */
740 static size_t
741 bvsnprintf(char **bufp, size_t *buflenp, const char *format, va_list alist)
742 {
743 size_t rv, len;
744
745 if (*buflenp == 0)
746 return (vsnprintf(NULL, 0, format, alist));
747
748 rv = vsnprintf(*bufp, *buflenp, format, alist);
749
750 len = MIN(rv, *buflenp);
751 *buflenp -= len;
752 *bufp += len;
753
754 return (len);
755 }
756
757 static size_t
758 bsnprintf(char **bufp, size_t *buflenp, const char *format, ...)
759 {
760 va_list alist;
761 size_t rv;
762
763 va_start(alist, format);
764 rv = bvsnprintf(bufp, buflenp, format, alist);
765 va_end(alist);
766
767 return (rv);
768 }
769
770 static void
771 v8_warn(const char *format, ...)
772 {
773 char buf[512];
774 va_list alist;
775 int len;
776
777 if (v8_silent)
778 return;
779
780 va_start(alist, format);
781 (void) vsnprintf(buf, sizeof (buf), format, alist);
782 va_end(alist);
783
784 /*
785 * This is made slightly annoying because we need to effectively
786 * preserve the original format string to allow for mdb to use the
787 * new-line at the end to indicate that strerror should be elided.
788 */
789 if ((len = strlen(format)) > 0 && format[len - 1] == '\n') {
790 buf[strlen(buf) - 1] = '\0';
791 mdb_warn("%s\n", buf);
792 } else {
793 mdb_warn("%s", buf);
794 }
795 }
796
797 /*
798 * Returns in "offp" the offset of field "field" in C++ class "klass".
799 */
800 static int
801 heap_offset(const char *klass, const char *field, ssize_t *offp)
802 {
803 v8_class_t *clp;
804 v8_field_t *flp;
805
806 for (clp = v8_classes; clp != NULL; clp = clp->v8c_next) {
807 if (strcmp(klass, clp->v8c_name) == 0)
808 break;
809 }
810
811 if (clp == NULL)
812 return (-1);
813
814 for (flp = clp->v8c_fields; flp != NULL; flp = flp->v8f_next) {
815 if (strcmp(field, flp->v8f_name) == 0)
816 break;
817 }
818
819 if (flp == NULL)
820 return (-1);
821
822 *offp = V8_OFF_HEAP(flp->v8f_offset);
823 return (0);
824 }
825
826 /*
827 * Assuming "addr" is an instance of the C++ heap class "klass", read into *valp
828 * the pointer-sized value of field "field".
829 */
830 static int
831 read_heap_ptr(uintptr_t *valp, uintptr_t addr, ssize_t off)
832 {
833 if (mdb_vread(valp, sizeof (*valp), addr + off) == -1) {
834 v8_warn("failed to read offset %d from %p", off, addr);
835 return (-1);
836 }
837
838 return (0);
839 }
840
841 /*
842 * Like read_heap_ptr, but assume the field is an SMI and store the actual value
843 * into *valp rather than the encoded representation.
844 */
845 static int
846 read_heap_smi(uintptr_t *valp, uintptr_t addr, ssize_t off)
847 {
848 if (read_heap_ptr(valp, addr, off) != 0)
849 return (-1);
850
851 if (!V8_IS_SMI(*valp)) {
852 v8_warn("expected SMI, got %p\n", *valp);
853 return (-1);
854 }
855
856 *valp = V8_SMI_VALUE(*valp);
857
858 return (0);
859 }
860
861 static int
862 read_heap_double(double *valp, uintptr_t addr, ssize_t off)
863 {
864 if (mdb_vread(valp, sizeof (*valp), addr + off) == -1) {
865 v8_warn("failed to read heap value at %p", addr + off);
866 return (-1);
867 }
868
869 return (0);
870 }
871
872 /*
873 * Assuming "addr" refers to a FixedArray, return a newly-allocated array
874 * representing its contents.
875 */
876 static int
877 read_heap_array(uintptr_t addr, uintptr_t **retp, size_t *lenp, int flags)
878 {
879 uint8_t type;
880 uintptr_t len;
881
882 if (!V8_IS_HEAPOBJECT(addr))
883 return (-1);
884
885 if (read_typebyte(&type, addr) != 0)
886 return (-1);
887
888 if (type != V8_TYPE_FIXEDARRAY)
889 return (-1);
890
891 if (read_heap_smi(&len, addr, V8_OFF_FIXEDARRAY_LENGTH) != 0)
892 return (-1);
893
894 *lenp = len;
895
896 if (len == 0) {
897 *retp = NULL;
898 return (0);
899 }
900
901 if ((*retp = mdb_zalloc(len * sizeof (uintptr_t), flags)) == NULL)
902 return (-1);
903
904 if (mdb_vread(*retp, len * sizeof (uintptr_t),
905 addr + V8_OFF_FIXEDARRAY_DATA) == -1) {
906 if (flags != UM_GC)
907 mdb_free(*retp, len * sizeof (uintptr_t));
908
909 return (-1);
910 }
911
912 return (0);
913 }
914
915 static int
916 read_heap_byte(uint8_t *valp, uintptr_t addr, ssize_t off)
917 {
918 if (mdb_vread(valp, sizeof (*valp), addr + off) == -1) {
919 v8_warn("failed to read heap value at %p", addr + off);
920 return (-1);
921 }
922
923 return (0);
924 }
925
926 /*
927 * Given a heap object, returns in *valp the byte describing the type of the
928 * object. This is shorthand for first retrieving the Map at the start of the
929 * heap object and then retrieving the type byte from the Map object.
930 */
931 static int
932 read_typebyte(uint8_t *valp, uintptr_t addr)
933 {
934 uintptr_t mapaddr;
935 ssize_t off = V8_OFF_HEAPOBJECT_MAP;
936
937 if (mdb_vread(&mapaddr, sizeof (mapaddr), addr + off) == -1) {
938 v8_warn("failed to read type of %p", addr);
939 return (-1);
940 }
941
942 if (!V8_IS_HEAPOBJECT(mapaddr)) {
943 v8_warn("object map is not a heap object\n");
944 return (-1);
945 }
946
947 if (read_heap_byte(valp, mapaddr, V8_OFF_MAP_INSTANCE_ATTRIBUTES) == -1)
948 return (-1);
949
950 return (0);
951 }
952
953 /*
954 * Given a heap object, returns in *valp the size of the object. For
955 * variable-size objects, returns an undefined value.
956 */
957 static int
958 read_size(size_t *valp, uintptr_t addr)
959 {
960 uintptr_t mapaddr;
961 uint8_t size;
962
963 if (read_heap_ptr(&mapaddr, addr, V8_OFF_HEAPOBJECT_MAP) != 0)
964 return (-1);
965
966 if (!V8_IS_HEAPOBJECT(mapaddr)) {
967 v8_warn("heap object map is not itself a heap object\n");
968 return (-1);
969 }
970
971 if (read_heap_byte(&size, mapaddr, V8_OFF_MAP_INSTANCE_SIZE) != 0)
972 return (-1);
973
974 *valp = size << V8_PointerSizeLog2;
975 return (0);
976 }
977
978 /*
979 * Returns in "buf" a description of the type of "addr" suitable for printing.
980 */
981 static int
982 obj_jstype(uintptr_t addr, char **bufp, size_t *lenp, uint8_t *typep)
983 {
984 uint8_t typebyte;
985 uintptr_t strptr;
986 const char *typename;
987
988 if (V8_IS_FAILURE(addr)) {
989 if (typep)
990 *typep = 0;
991 (void) bsnprintf(bufp, lenp, "'Failure' object");
992 return (0);
993 }
994
995 if (V8_IS_SMI(addr)) {
996 if (typep)
997 *typep = 0;
998 (void) bsnprintf(bufp, lenp, "SMI: value = %d",
999 V8_SMI_VALUE(addr));
1000 return (0);
1001 }
1002
1003 if (read_typebyte(&typebyte, addr) != 0)
1004 return (-1);
1005
1006 if (typep)
1007 *typep = typebyte;
1008
1009 typename = enum_lookup_str(v8_types, typebyte, "<unknown>");
1010 (void) bsnprintf(bufp, lenp, typename);
1011
1012 if (strcmp(typename, "Oddball") == 0) {
1013 if (read_heap_ptr(&strptr, addr,
1014 V8_OFF_ODDBALL_TO_STRING) != -1) {
1015 (void) bsnprintf(bufp, lenp, ": \"");
1016 (void) jsstr_print(strptr, B_FALSE, bufp, lenp);
1017 (void) bsnprintf(bufp, lenp, "\"");
1018 }
1019 }
1020
1021 return (0);
1022 }
1023
1024 /*
1025 * Print out the fields of the given object that come from the given class.
1026 */
1027 static int
1028 obj_print_fields(uintptr_t baddr, v8_class_t *clp)
1029 {
1030 v8_field_t *flp;
1031 uintptr_t addr, value;
1032 int rv;
1033 char *bufp;
1034 size_t len;
1035 uint8_t type;
1036 char buf[256];
1037
1038 for (flp = clp->v8c_fields; flp != NULL; flp = flp->v8f_next) {
1039 bufp = buf;
1040 len = sizeof (buf);
1041
1042 addr = baddr + V8_OFF_HEAP(flp->v8f_offset);
1043
1044 if (flp->v8f_isbyte) {
1045 uint8_t sv;
1046 if (mdb_vread(&sv, sizeof (sv), addr) == -1) {
1047 mdb_printf("%p %s (unreadable)\n",
1048 addr, flp->v8f_name);
1049 continue;
1050 }
1051
1052 mdb_printf("%p %s = 0x%x\n", addr, flp->v8f_name, sv);
1053 continue;
1054 }
1055
1056 rv = mdb_vread((void *)&value, sizeof (value), addr);
1057
1058 if (rv != sizeof (value) ||
1059 obj_jstype(value, &bufp, &len, &type) != 0) {
1060 mdb_printf("%p %s (unreadable)\n", addr, flp->v8f_name);
1061 continue;
1062 }
1063
1064 if (type != 0 && V8_TYPE_STRING(type)) {
1065 (void) bsnprintf(&bufp, &len, ": \"");
1066 (void) jsstr_print(value, B_FALSE, &bufp, &len);
1067 (void) bsnprintf(&bufp, &len, "\"");
1068 }
1069
1070 mdb_printf("%p %s = %p (%s)\n", addr, flp->v8f_name, value,
1071 buf);
1072 }
1073
1074 return (DCMD_OK);
1075 }
1076
1077 /*
1078 * Print out all fields of the given object, starting with the root of the class
1079 * hierarchy and working down the most specific type.
1080 */
1081 static int
1082 obj_print_class(uintptr_t addr, v8_class_t *clp)
1083 {
1084 int rv = 0;
1085
1086 /*
1087 * If we have no fields, we just print a simple inheritance hierarchy.
1088 * If we have fields but our parent doesn't, our header includes the
1089 * inheritance hierarchy.
1090 */
1091 if (clp->v8c_end == 0) {
1092 mdb_printf("%s ", clp->v8c_name);
1093
1094 if (clp->v8c_parent != NULL) {
1095 mdb_printf("< ");
1096 (void) obj_print_class(addr, clp->v8c_parent);
1097 }
1098
1099 return (0);
1100 }
1101
1102 mdb_printf("%p %s", addr, clp->v8c_name);
1103
1104 if (clp->v8c_start == 0 && clp->v8c_parent != NULL) {
1105 mdb_printf(" < ");
1106 (void) obj_print_class(addr, clp->v8c_parent);
1107 }
1108
1109 mdb_printf(" {\n");
1110 (void) mdb_inc_indent(4);
1111
1112 if (clp->v8c_start > 0 && clp->v8c_parent != NULL)
1113 rv = obj_print_class(addr, clp->v8c_parent);
1114
1115 rv |= obj_print_fields(addr, clp);
1116 (void) mdb_dec_indent(4);
1117 mdb_printf("}\n");
1118
1119 return (rv);
1120 }
1121
1122 /*
1123 * Print the ASCII string for the given ASCII JS string, expanding ConsStrings
1124 * and ExternalStrings as needed.
1125 */
1126 static int jsstr_print_seq(uintptr_t, boolean_t, char **, size_t *);
1127 static int jsstr_print_cons(uintptr_t, boolean_t, char **, size_t *);
1128 static int jsstr_print_external(uintptr_t, boolean_t, char **, size_t *);
1129
1130 static int
1131 jsstr_print(uintptr_t addr, boolean_t verbose, char **bufp, size_t *lenp)
1132 {
1133 uint8_t typebyte;
1134 int err = 0;
1135 char *lbufp;
1136 size_t llen;
1137 char buf[64];
1138
1139 if (read_typebyte(&typebyte, addr) != 0)
1140 return (0);
1141
1142 if (!V8_TYPE_STRING(typebyte)) {
1143 (void) bsnprintf(bufp, lenp, "<not a string>");
1144 return (0);
1145 }
1146
1147 if (!V8_STRENC_ASCII(typebyte)) {
1148 (void) bsnprintf(bufp, lenp, "<two-byte string>");
1149 return (0);
1150 }
1151
1152 if (verbose) {
1153 lbufp = buf;
1154 llen = sizeof (buf);
1155 (void) obj_jstype(addr, &lbufp, &llen, NULL);
1156 mdb_printf("%s\n", buf);
1157 (void) mdb_inc_indent(4);
1158 }
1159
1160 if (V8_STRREP_SEQ(typebyte))
1161 err = jsstr_print_seq(addr, verbose, bufp, lenp);
1162 else if (V8_STRREP_CONS(typebyte))
1163 err = jsstr_print_cons(addr, verbose, bufp, lenp);
1164 else if (V8_STRREP_EXT(typebyte))
1165 err = jsstr_print_external(addr, verbose, bufp, lenp);
1166 else {
1167 (void) bsnprintf(bufp, lenp, "<unknown string type>");
1168 err = -1;
1169 }
1170
1171 if (verbose)
1172 (void) mdb_dec_indent(4);
1173
1174 return (err);
1175 }
1176
1177 static int
1178 jsstr_print_seq(uintptr_t addr, boolean_t verbose, char **bufp, size_t *lenp)
1179 {
1180 uintptr_t len, rlen;
1181 char buf[256];
1182
1183 if (read_heap_smi(&len, addr, V8_OFF_STRING_LENGTH) != 0)
1184 return (-1);
1185
1186 rlen = len <= sizeof (buf) - 1 ? len : sizeof (buf) - sizeof ("[...]");
1187
1188 if (verbose)
1189 mdb_printf("length: %d, will read: %d\n", len, rlen);
1190
1191 buf[0] = '\0';
1192
1193 if (rlen > 0 && mdb_readstr(buf, rlen + 1,
1194 addr + V8_OFF_SEQASCIISTR_CHARS) == -1) {
1195 v8_warn("failed to read SeqString data");
1196 return (-1);
1197 }
1198
1199 if (rlen != len)
1200 (void) strlcat(buf, "[...]", sizeof (buf));
1201
1202 if (verbose)
1203 mdb_printf("value: \"%s\"\n", buf);
1204
1205 (void) bsnprintf(bufp, lenp, "%s", buf);
1206 return (0);
1207 }
1208
1209 static int
1210 jsstr_print_cons(uintptr_t addr, boolean_t verbose, char **bufp, size_t *lenp)
1211 {
1212 uintptr_t ptr1, ptr2;
1213
1214 if (read_heap_ptr(&ptr1, addr, V8_OFF_CONSSTRING_FIRST) != 0 ||
1215 read_heap_ptr(&ptr2, addr, V8_OFF_CONSSTRING_SECOND) != 0)
1216 return (-1);
1217
1218 if (verbose) {
1219 mdb_printf("ptr1: %p\n", ptr1);
1220 mdb_printf("ptr2: %p\n", ptr2);
1221 }
1222
1223 if (jsstr_print(ptr1, verbose, bufp, lenp) != 0)
1224 return (-1);
1225
1226 return (jsstr_print(ptr2, verbose, bufp, lenp));
1227 }
1228
1229 static int
1230 jsstr_print_external(uintptr_t addr, boolean_t verbose, char **bufp,
1231 size_t *lenp)
1232 {
1233 uintptr_t ptr1, ptr2;
1234 char buf[256];
1235
1236 if (verbose)
1237 mdb_printf("assuming Node.js string\n");
1238
1239 if (read_heap_ptr(&ptr1, addr, V8_OFF_EXTERNALSTRING_RESOURCE) != 0)
1240 return (-1);
1241
1242 if (mdb_vread(&ptr2, sizeof (ptr2),
1243 ptr1 + NODE_OFF_EXTSTR_DATA) == -1) {
1244 v8_warn("failed to read node external pointer: %p",
1245 ptr1 + NODE_OFF_EXTSTR_DATA);
1246 return (-1);
1247 }
1248
1249 if (mdb_readstr(buf, sizeof (buf), ptr2) == -1) {
1250 v8_warn("failed to read ExternalString data");
1251 return (-1);
1252 }
1253
1254 if (buf[0] != '\0' && !isascii(buf[0])) {
1255 v8_warn("failed to read ExternalString ascii data\n");
1256 return (-1);
1257 }
1258
1259 (void) bsnprintf(bufp, lenp, "%s", buf);
1260 return (0);
1261 }
1262
1263 /*
1264 * Returns true if the given address refers to the "undefined" object. Returns
1265 * false on failure (since we shouldn't fail on the actual "undefined" value).
1266 */
1267 static boolean_t
1268 jsobj_is_undefined(uintptr_t addr)
1269 {
1270 uint8_t type;
1271 uintptr_t strptr;
1272 const char *typename;
1273 char buf[16];
1274 char *bufp = buf;
1275 size_t len = sizeof (buf);
1276
1277 v8_silent++;
1278
1279 if (read_typebyte(&type, addr) != 0) {
1280 v8_silent--;
1281 return (B_FALSE);
1282 }
1283
1284 v8_silent--;
1285
1286 typename = enum_lookup_str(v8_types, type, "<unknown>");
1287 if (strcmp(typename, "Oddball") != 0)
1288 return (B_FALSE);
1289
1290 if (read_heap_ptr(&strptr, addr, V8_OFF_ODDBALL_TO_STRING) == -1)
1291 return (B_FALSE);
1292
1293 if (jsstr_print(strptr, B_FALSE, &bufp, &len) != 0)
1294 return (B_FALSE);
1295
1296 return (strcmp(buf, "undefined") == 0);
1297 }
1298
1299 static int
1300 jsobj_properties(uintptr_t addr,
1301 int (*func)(const char *, uintptr_t, void *), void *arg)
1302 {
1303 uintptr_t ptr, map;
1304 uintptr_t *props = NULL, *descs = NULL, *content = NULL, *trans;
1305 size_t size, nprops, ndescs, ncontent, ntrans;
1306 ssize_t ii, rndescs;
1307 uint8_t type, ninprops;
1308 int rval = -1;
1309 size_t ps = sizeof (uintptr_t);
1310 ssize_t off;
1311
1312 /*
1313 * Objects have either "fast" properties represented with a FixedArray
1314 * or slow properties represented with a Dictionary. We only support
1315 * the former, so we check that up front.
1316 */
1317 if (mdb_vread(&ptr, ps, addr + V8_OFF_JSOBJECT_PROPERTIES) == -1)
1318 return (-1);
1319
1320 if (read_typebyte(&type, ptr) != 0)
1321 return (-1);
1322
1323 if (type != V8_TYPE_FIXEDARRAY)
1324 return (func(NULL, 0, arg));
1325
1326 if (read_heap_array(ptr, &props, &nprops, UM_SLEEP) != 0)
1327 return (-1);
1328
1329 /*
1330 * To iterate the properties, we need to examine the instance
1331 * descriptors of the associated Map object. Depending on the version
1332 * of V8, this might be found directly from the map -- or indirectly
1333 * via the transitions array.
1334 */
1335 if (mdb_vread(&map, ps, addr + V8_OFF_HEAPOBJECT_MAP) == -1)
1336 goto err;
1337
1338 if ((off = V8_OFF_MAP_INSTANCE_DESCRIPTORS) == -1) {
1339 if (V8_OFF_MAP_TRANSITIONS == -1 ||
1340 V8_TRANSITIONS_IDX_DESC == -1 ||
1341 V8_PROP_IDX_CONTENT != -1) {
1342 mdb_warn("missing instance_descriptors, but did "
1343 "not find expected transitions array metadata; "
1344 "cannot read properties\n");
1345 goto err;
1346 }
1347
1348 off = V8_OFF_MAP_TRANSITIONS;
1349 }
1350
1351 if (mdb_vread(&ptr, ps, map + off) == -1)
1352 goto err;
1353
1354 if (V8_OFF_MAP_TRANSITIONS != -1) {
1355 if (read_heap_array(ptr, &trans, &ntrans, UM_SLEEP) != 0)
1356 goto err;
1357
1358 ptr = trans[V8_TRANSITIONS_IDX_DESC];
1359 mdb_free(trans, ntrans * sizeof (uintptr_t));
1360 }
1361
1362 if (read_heap_array(ptr, &descs, &ndescs, UM_SLEEP) != 0)
1363 goto err;
1364
1365 if (read_size(&size, addr) != 0)
1366 size = 0;
1367
1368 if (mdb_vread(&ninprops, 1, map + V8_OFF_MAP_INOBJECT_PROPERTIES) == -1)
1369 goto err;
1370
1371 if (V8_PROP_IDX_CONTENT != -1 && V8_PROP_IDX_CONTENT < ndescs &&
1372 read_heap_array(descs[V8_PROP_IDX_CONTENT], &content,
1373 &ncontent, UM_SLEEP) != 0)
1374 goto err;
1375
1376 if ((V8_PROP_IDX_CONTENT == -1 && V8_PROP_DESC_SIZE == -1) ||
1377 (V8_PROP_IDX_CONTENT != -1 && V8_PROP_DESC_SIZE != -1)) {
1378 /*
1379 * Exactly one of these must be set; if they're both unset or
1380 * both set (that is, if the -- ahem -- logical xor of being
1381 * set evaluates to false), we have a misconfiguration.
1382 */
1383 mdb_warn("v8dbg_prop_idx_content (%ld) is inconsistent with "
1384 "v8dbg_prop_desc_size (%ld); cannot read properties\n",
1385 V8_PROP_IDX_CONTENT, V8_PROP_DESC_SIZE);
1386 goto err;
1387 }
1388
1389 if (V8_PROP_IDX_CONTENT == -1) {
1390 /*
1391 * On node v0.8 and later, the content is not stored in an
1392 * orthogonal FixedArray, but rather with the descriptors.
1393 */
1394 content = descs;
1395 ncontent = ndescs;
1396 rndescs = ndescs > V8_PROP_IDX_FIRST ?
1397 (ndescs - V8_PROP_IDX_FIRST) / V8_PROP_DESC_SIZE : 0;
1398 } else {
1399 rndescs = ndescs - V8_PROP_IDX_FIRST;
1400 }
1401
1402 for (ii = 0; ii < rndescs; ii++) {
1403 uintptr_t keyidx, validx, detidx, baseidx;
1404 char buf[1024];
1405 intptr_t val;
1406 uint_t len = sizeof (buf);
1407 char *c = buf;
1408
1409 if (V8_PROP_IDX_CONTENT != -1) {
1410 /*
1411 * In node versions prior to v0.8, this was hardcoded
1412 * in the V8 implementation, so we hardcode it here
1413 * as well.
1414 */
1415 keyidx = ii + V8_PROP_IDX_FIRST;
1416 validx = ii << 1;
1417 detidx = (ii << 1) + 1;
1418 } else {
1419 baseidx = V8_PROP_IDX_FIRST + (ii * V8_PROP_DESC_SIZE);
1420 keyidx = baseidx + V8_PROP_DESC_KEY;
1421 validx = baseidx + V8_PROP_DESC_VALUE;
1422 detidx = baseidx + V8_PROP_DESC_DETAILS;
1423 }
1424
1425 if (detidx >= ncontent) {
1426 v8_warn("property descriptor %d: detidx (%d) "
1427 "out of bounds for content array (length %d)\n",
1428 ii, detidx, ncontent);
1429 continue;
1430 }
1431
1432 if (content != descs && !V8_DESC_ISFIELD(content[detidx]))
1433 continue;
1434
1435 if (keyidx >= ndescs) {
1436 v8_warn("property descriptor %d: keyidx (%d) "
1437 "out of bounds for descriptor array (length %d)\n",
1438 ii, keyidx, ndescs);
1439 continue;
1440 }
1441
1442 if (jsstr_print(descs[keyidx], B_FALSE, &c, &len) != 0)
1443 continue;
1444
1445 val = (intptr_t)content[validx];
1446
1447 if (!V8_IS_SMI(val)) {
1448 v8_warn("property descriptor %d: value index value "
1449 "is not an SMI: %p\n", ii, val);
1450 continue;
1451 }
1452
1453 val = V8_SMI_VALUE(val) - ninprops;
1454
1455 if (val < 0) {
1456 /* property is stored directly in the object */
1457 if (mdb_vread(&ptr, sizeof (ptr), addr + V8_OFF_HEAP(
1458 size + val * sizeof (uintptr_t))) == -1) {
1459 v8_warn("failed to read in-object "
1460 "property at %p\n", addr + V8_OFF_HEAP(
1461 size + val * sizeof (uintptr_t)));
1462 continue;
1463 }
1464 } else {
1465 /* property should be in "props" array */
1466 if (val >= nprops) {
1467 v8_warn("property descriptor %d: value index "
1468 "value (%d) out of bounds (%d)\n", ii, val,
1469 nprops);
1470 continue;
1471 }
1472
1473 ptr = props[val];
1474 }
1475
1476 if (func(buf, ptr, arg) != 0)
1477 goto err;
1478 }
1479
1480 rval = 0;
1481 err:
1482 if (props != NULL)
1483 mdb_free(props, nprops * sizeof (uintptr_t));
1484
1485 if (descs != NULL)
1486 mdb_free(descs, ndescs * sizeof (uintptr_t));
1487
1488 if (content != NULL && V8_PROP_IDX_CONTENT != -1)
1489 mdb_free(content, ncontent * sizeof (uintptr_t));
1490
1491 return (rval);
1492 }
1493
1494 /*
1495 * Given the line endings table in "lendsp", computes the line number for the
1496 * given token position and print the result into "buf". If "lendsp" is
1497 * undefined, prints the token position instead.
1498 */
1499 static int
1500 jsfunc_lineno(uintptr_t lendsp, uintptr_t tokpos, char *buf, size_t buflen)
1501 {
1502 uintptr_t size, bufsz, lower, upper, ii;
1503 uintptr_t *data;
1504
1505 if (jsobj_is_undefined(lendsp)) {
1506 /*
1507 * The token position is an SMI, but it comes in as its raw
1508 * value so we can more easily compare it to values in the line
1509 * endings table. If we're just printing the position directly,
1510 * we must convert it here.
1511 */
1512 mdb_snprintf(buf, buflen, "position %d", V8_SMI_VALUE(tokpos));
1513 return (0);
1514 }
1515
1516 if (read_heap_smi(&size, lendsp, V8_OFF_FIXEDARRAY_LENGTH) != 0)
1517 return (-1);
1518
1519 bufsz = size * sizeof (data[0]);
1520
1521 if ((data = mdb_alloc(bufsz, UM_NOSLEEP)) == NULL) {
1522 v8_warn("failed to alloc %d bytes for FixedArray data", bufsz);
1523 return (-1);
1524 }
1525
1526 if (mdb_vread(data, bufsz, lendsp + V8_OFF_FIXEDARRAY_DATA) != bufsz) {
1527 v8_warn("failed to read FixedArray data");
1528 mdb_free(data, bufsz);
1529 return (-1);
1530 }
1531
1532 lower = 0;
1533 upper = size - 1;
1534
1535 if (tokpos > data[upper]) {
1536 (void) strlcpy(buf, "position out of range", buflen);
1537 mdb_free(data, bufsz);
1538 return (0);
1539 }
1540
1541 if (tokpos <= data[0]) {
1542 (void) strlcpy(buf, "line 1", buflen);
1543 mdb_free(data, bufsz);
1544 return (0);
1545 }
1546
1547 while (upper >= 1) {
1548 ii = (lower + upper) >> 1;
1549 if (tokpos > data[ii])
1550 lower = ii + 1;
1551 else if (tokpos <= data[ii - 1])
1552 upper = ii - 1;
1553 else
1554 break;
1555 }
1556
1557 (void) mdb_snprintf(buf, buflen, "line %d", ii + 1);
1558 mdb_free(data, bufsz);
1559 return (0);
1560 }
1561
1562 /*
1563 * Given a SharedFunctionInfo object, prints into bufp a name of the function
1564 * suitable for printing. This function attempts to infer a name for anonymous
1565 * functions.
1566 */
1567 static int
1568 jsfunc_name(uintptr_t funcinfop, char **bufp, size_t *lenp)
1569 {
1570 uintptr_t ptrp;
1571 char *bufs = *bufp;
1572
1573 if (read_heap_ptr(&ptrp, funcinfop,
1574 V8_OFF_SHAREDFUNCTIONINFO_NAME) != 0 ||
1575 jsstr_print(ptrp, B_FALSE, bufp, lenp) != 0)
1576 return (-1);
1577
1578 if (*bufp != bufs)
1579 return (0);
1580
1581 if (read_heap_ptr(&ptrp, funcinfop,
1582 V8_OFF_SHAREDFUNCTIONINFO_INFERRED_NAME) != 0) {
1583 (void) bsnprintf(bufp, lenp, "<anonymous>");
1584 return (0);
1585 }
1586
1587 (void) bsnprintf(bufp, lenp, "<anonymous> (as ");
1588 bufs = *bufp;
1589
1590 if (jsstr_print(ptrp, B_FALSE, bufp, lenp) != 0)
1591 return (-1);
1592
1593 if (*bufp == bufs)
1594 (void) bsnprintf(bufp, lenp, "<anon>");
1595
1596 (void) bsnprintf(bufp, lenp, ")");
1597
1598 return (0);
1599 }
1600
1601 /*
1602 * JavaScript-level object printing
1603 */
1604 typedef struct jsobj_print {
1605 char **jsop_bufp;
1606 size_t *jsop_lenp;
1607 int jsop_indent;
1608 uint64_t jsop_depth;
1609 boolean_t jsop_printaddr;
1610 int jsop_nprops;
1611 } jsobj_print_t;
1612
1613 static int jsobj_print_number(uintptr_t, jsobj_print_t *);
1614 static int jsobj_print_oddball(uintptr_t, jsobj_print_t *);
1615 static int jsobj_print_jsobject(uintptr_t, jsobj_print_t *);
1616 static int jsobj_print_jsarray(uintptr_t, jsobj_print_t *);
1617 static int jsobj_print_jsfunction(uintptr_t, jsobj_print_t *);
1618
1619 static int
1620 jsobj_print(uintptr_t addr, jsobj_print_t *jsop)
1621 {
1622 uint8_t type;
1623 const char *klass;
1624 char **bufp = jsop->jsop_bufp;
1625 size_t *lenp = jsop->jsop_lenp;
1626
1627 const struct {
1628 char *name;
1629 int (*func)(uintptr_t, jsobj_print_t *);
1630 } table[] = {
1631 { "HeapNumber", jsobj_print_number },
1632 { "Oddball", jsobj_print_oddball },
1633 { "JSObject", jsobj_print_jsobject },
1634 { "JSArray", jsobj_print_jsarray },
1635 { "JSFunction", jsobj_print_jsfunction },
1636 { NULL }
1637 }, *ent;
1638
1639 if (jsop->jsop_printaddr)
1640 (void) bsnprintf(bufp, lenp, "%p: ", addr);
1641
1642 if (V8_IS_SMI(addr)) {
1643 (void) bsnprintf(bufp, lenp, "%d", V8_SMI_VALUE(addr));
1644 return (0);
1645 }
1646
1647 if (!V8_IS_HEAPOBJECT(addr)) {
1648 v8_warn("not a heap object: %p\n", addr);
1649 return (-1);
1650 }
1651
1652 if (read_typebyte(&type, addr) != 0)
1653 return (-1);
1654
1655 if (V8_TYPE_STRING(type))
1656 return (jsstr_print(addr, B_FALSE, bufp, lenp));
1657
1658 klass = enum_lookup_str(v8_types, type, "<unknown>");
1659
1660 for (ent = &table[0]; ent->name != NULL; ent++) {
1661 if (strcmp(klass, ent->name) == 0)
1662 return (ent->func(addr, jsop));
1663 }
1664
1665 v8_warn("unknown JavaScript object type \"%s\"\n", klass);
1666 return (-1);
1667 }
1668
1669 static int
1670 jsobj_print_number(uintptr_t addr, jsobj_print_t *jsop)
1671 {
1672 char **bufp = jsop->jsop_bufp;
1673 size_t *lenp = jsop->jsop_lenp;
1674 double numval;
1675
1676 if (read_heap_double(&numval, addr, V8_OFF_HEAPNUMBER_VALUE) == -1)
1677 return (-1);
1678
1679 if (numval == (long long)numval)
1680 (void) bsnprintf(bufp, lenp, "%lld", (long long)numval);
1681 else
1682 (void) bsnprintf(bufp, lenp, "%e", numval);
1683
1684 return (0);
1685 }
1686
1687 static int
1688 jsobj_print_oddball(uintptr_t addr, jsobj_print_t *jsop)
1689 {
1690 char **bufp = jsop->jsop_bufp;
1691 size_t *lenp = jsop->jsop_lenp;
1692 uintptr_t strptr;
1693
1694 if (read_heap_ptr(&strptr, addr, V8_OFF_ODDBALL_TO_STRING) != 0)
1695 return (-1);
1696
1697 return (jsstr_print(strptr, B_FALSE, bufp, lenp));
1698 }
1699
1700 static int
1701 jsobj_print_prop(const char *desc, uintptr_t val, void *arg)
1702 {
1703 jsobj_print_t *jsop = arg, descend;
1704 char **bufp = jsop->jsop_bufp;
1705 size_t *lenp = jsop->jsop_lenp;
1706
1707 if (desc == NULL) {
1708 jsop->jsop_nprops = -1;
1709 return (0);
1710 }
1711
1712 (void) bsnprintf(bufp, lenp, "%s\n%*s%s: ", jsop->jsop_nprops == 0 ?
1713 "{" : "", jsop->jsop_indent + 4, "", desc);
1714
1715 descend = *jsop;
1716 descend.jsop_depth--;
1717 descend.jsop_indent += 4;
1718
1719 (void) jsobj_print(val, &descend);
1720 (void) bsnprintf(bufp, lenp, ",");
1721
1722 jsop->jsop_nprops++;
1723
1724 return (0);
1725 }
1726
1727 static int
1728 jsobj_print_jsobject(uintptr_t addr, jsobj_print_t *jsop)
1729 {
1730 char **bufp = jsop->jsop_bufp;
1731 size_t *lenp = jsop->jsop_lenp;
1732
1733 if (jsop->jsop_depth == 0) {
1734 (void) bsnprintf(bufp, lenp, "[...]");
1735 return (0);
1736 }
1737
1738 jsop->jsop_nprops = 0;
1739
1740 if (jsobj_properties(addr, jsobj_print_prop, jsop) != 0)
1741 return (-1);
1742
1743 if (jsop->jsop_nprops > 0) {
1744 (void) bsnprintf(bufp, lenp, "\n%*s", jsop->jsop_indent, "");
1745 } else if (jsop->jsop_nprops == 0) {
1746 (void) bsnprintf(bufp, lenp, "{");
1747 } else {
1748 (void) bsnprintf(bufp, lenp, "{ /* unknown property */ ");
1749 }
1750
1751 (void) bsnprintf(bufp, lenp, "}");
1752
1753 return (0);
1754 }
1755
1756 static int
1757 jsobj_print_jsarray(uintptr_t addr, jsobj_print_t *jsop)
1758 {
1759 char **bufp = jsop->jsop_bufp;
1760 size_t *lenp = jsop->jsop_lenp;
1761 int indent = jsop->jsop_indent;
1762 jsobj_print_t descend;
1763 uintptr_t ptr;
1764 uintptr_t *elts;
1765 size_t ii, len;
1766
1767 if (jsop->jsop_depth == 0) {
1768 (void) bsnprintf(bufp, lenp, "[...]");
1769 return (0);
1770 }
1771
1772 if (read_heap_ptr(&ptr, addr, V8_OFF_JSOBJECT_ELEMENTS) != 0 ||
1773 read_heap_array(ptr, &elts, &len, UM_GC) != 0)
1774 return (-1);
1775
1776 if (len == 0) {
1777 (void) bsnprintf(bufp, lenp, "[]");
1778 return (0);
1779 }
1780
1781 descend = *jsop;
1782 descend.jsop_depth--;
1783 descend.jsop_indent += 4;
1784
1785 if (len == 1) {
1786 (void) bsnprintf(bufp, lenp, "[ ");
1787 (void) jsobj_print(elts[0], &descend);
1788 (void) bsnprintf(bufp, lenp, " ]");
1789 return (0);
1790 }
1791
1792 (void) bsnprintf(bufp, lenp, "[\n");
1793
1794 for (ii = 0; ii < len; ii++) {
1795 (void) bsnprintf(bufp, lenp, "%*s", indent + 4, "");
1796 (void) jsobj_print(elts[ii], &descend);
1797 (void) bsnprintf(bufp, lenp, ",\n");
1798 }
1799
1800 (void) bsnprintf(bufp, lenp, "%*s", indent, "");
1801 (void) bsnprintf(bufp, lenp, "]");
1802
1803 return (0);
1804 }
1805
1806 static int
1807 jsobj_print_jsfunction(uintptr_t addr, jsobj_print_t *jsop)
1808 {
1809 char **bufp = jsop->jsop_bufp;
1810 size_t *lenp = jsop->jsop_lenp;
1811 uintptr_t shared;
1812
1813 if (read_heap_ptr(&shared, addr, V8_OFF_JSFUNCTION_SHARED) != 0)
1814 return (-1);
1815
1816 (void) bsnprintf(bufp, lenp, "function ");
1817 return (jsfunc_name(shared, bufp, lenp) != 0);
1818 }
1819
1820 /*
1821 * dcmd implementations
1822 */
1823
1824 /* ARGSUSED */
1825 static int
1826 dcmd_v8classes(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
1827 {
1828 v8_class_t *clp;
1829
1830 for (clp = v8_classes; clp != NULL; clp = clp->v8c_next)
1831 mdb_printf("%s\n", clp->v8c_name);
1832
1833 return (DCMD_OK);
1834 }
1835
1836 static int
1837 do_v8code(uintptr_t addr, boolean_t opt_d)
1838 {
1839 uintptr_t instrlen;
1840 ssize_t instroff = V8_OFF_CODE_INSTRUCTION_START;
1841
1842 if (read_heap_ptr(&instrlen, addr, V8_OFF_CODE_INSTRUCTION_SIZE) != 0)
1843 return (DCMD_ERR);
1844
1845 mdb_printf("code: %p\n", addr);
1846 mdb_printf("instructions: [%p, %p)\n", addr + instroff,
1847 addr + instroff + instrlen);
1848
1849 if (!opt_d)
1850 return (DCMD_OK);
1851
1852 mdb_set_dot(addr + instroff);
1853
1854 do {
1855 (void) mdb_inc_indent(8); /* gets reset by mdb_eval() */
1856
1857 /*
1858 * This is absolutely awful. We want to disassemble the above
1859 * range of instructions. Because we don't know how many there
1860 * are, we can't use "::dis". We resort to evaluating "./i",
1861 * but then we need to advance "." by the size of the
1862 * instruction just printed. The only way to do that is by
1863 * printing out "+", but we don't want that to show up, so we
1864 * redirect it to /dev/null.
1865 */
1866 if (mdb_eval("/i") != 0 ||
1867 mdb_eval("+=p ! cat > /dev/null") != 0) {
1868 (void) mdb_dec_indent(8);
1869 v8_warn("failed to disassemble at %p", mdb_get_dot());
1870 return (DCMD_ERR);
1871 }
1872 } while (mdb_get_dot() < addr + instroff + instrlen);
1873
1874 (void) mdb_dec_indent(8);
1875 return (DCMD_OK);
1876 }
1877
1878 /* ARGSUSED */
1879 static int
1880 dcmd_v8code(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
1881 {
1882 boolean_t opt_d = B_FALSE;
1883
1884 if (mdb_getopts(argc, argv, 'd', MDB_OPT_SETBITS, B_TRUE, &opt_d,
1885 NULL) != argc)
1886 return (DCMD_USAGE);
1887
1888 return (do_v8code(addr, opt_d));
1889 }
1890
1891 /* ARGSUSED */
1892 static int
1893 dcmd_v8function(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
1894 {
1895 uint8_t type;
1896 uintptr_t funcinfop, scriptp, lendsp, tokpos, namep, codep;
1897 char *bufp;
1898 uint_t len;
1899 boolean_t opt_d = B_FALSE;
1900 char buf[512];
1901
1902 if (mdb_getopts(argc, argv, 'd', MDB_OPT_SETBITS, B_TRUE, &opt_d,
1903 NULL) != argc)
1904 return (DCMD_USAGE);
1905
1906 if (read_typebyte(&type, addr) != 0)
1907 return (DCMD_ERR);
1908
1909 if (strcmp(enum_lookup_str(v8_types, type, ""), "JSFunction") != 0) {
1910 v8_warn("%p is not an instance of JSFunction\n", addr);
1911 return (DCMD_ERR);
1912 }
1913
1914 if (read_heap_ptr(&funcinfop, addr, V8_OFF_JSFUNCTION_SHARED) != 0 ||
1915 read_heap_ptr(&tokpos, funcinfop,
1916 V8_OFF_SHAREDFUNCTIONINFO_FUNCTION_TOKEN_POSITION) != 0 ||
1917 read_heap_ptr(&scriptp, funcinfop,
1918 V8_OFF_SHAREDFUNCTIONINFO_SCRIPT) != 0 ||
1919 read_heap_ptr(&namep, scriptp, V8_OFF_SCRIPT_NAME) != 0 ||
1920 read_heap_ptr(&lendsp, scriptp, V8_OFF_SCRIPT_LINE_ENDS) != 0)
1921 return (DCMD_ERR);
1922
1923 bufp = buf;
1924 len = sizeof (buf);
1925 if (jsfunc_name(funcinfop, &bufp, &len) != 0)
1926 return (DCMD_ERR);
1927
1928 mdb_printf("%p: JSFunction: %s\n", addr, buf);
1929
1930 bufp = buf;
1931 len = sizeof (buf);
1932 mdb_printf("defined at ");
1933
1934 if (jsstr_print(namep, B_FALSE, &bufp, &len) == 0)
1935 mdb_printf("%s ", buf);
1936
1937 if (jsfunc_lineno(lendsp, tokpos, buf, sizeof (buf)) == 0)
1938 mdb_printf("%s", buf);
1939
1940 mdb_printf("\n");
1941
1942 if (read_heap_ptr(&codep,
1943 funcinfop, V8_OFF_SHAREDFUNCTIONINFO_CODE) != 0)
1944 return (DCMD_ERR);
1945
1946 return (do_v8code(codep, opt_d));
1947 }
1948
1949 /* ARGSUSED */
1950 static int
1951 dcmd_v8frametypes(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
1952 {
1953 enum_print(v8_frametypes);
1954 return (DCMD_OK);
1955 }
1956
1957 static void
1958 dcmd_v8print_help(void)
1959 {
1960 mdb_printf(
1961 "Prints out \".\" (a V8 heap object) as an instance of its C++\n"
1962 "class. With no arguments, the appropriate class is detected\n"
1963 "automatically. The 'class' argument overrides this to print an\n"
1964 "object as an instance of the given class. The list of known\n"
1965 "classes can be viewed with ::jsclasses.");
1966 }
1967
1968 /* ARGSUSED */
1969 static int
1970 dcmd_v8print(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
1971 {
1972 const char *rqclass;
1973 v8_class_t *clp;
1974 char *bufp;
1975 size_t len;
1976 uint8_t type;
1977 char buf[256];
1978
1979 if (argc < 1) {
1980 /*
1981 * If no type was specified, determine it automatically.
1982 */
1983 bufp = buf;
1984 len = sizeof (buf);
1985 if (obj_jstype(addr, &bufp, &len, &type) != 0)
1986 return (DCMD_ERR);
1987
1988 if (type == 0) {
1989 /* For SMI or Failure, just print out the type. */
1990 mdb_printf("%s\n", buf);
1991 return (DCMD_OK);
1992 }
1993
1994 if ((rqclass = enum_lookup_str(v8_types, type, NULL)) == NULL) {
1995 v8_warn("object has unknown type\n");
1996 return (DCMD_ERR);
1997 }
1998 } else {
1999 if (argv[0].a_type != MDB_TYPE_STRING)
2000 return (DCMD_USAGE);
2001
2002 rqclass = argv[0].a_un.a_str;
2003 }
2004
2005 for (clp = v8_classes; clp != NULL; clp = clp->v8c_next) {
2006 if (strcmp(rqclass, clp->v8c_name) == 0)
2007 break;
2008 }
2009
2010 if (clp == NULL) {
2011 v8_warn("unknown class '%s'\n", rqclass);
2012 return (DCMD_USAGE);
2013 }
2014
2015 return (obj_print_class(addr, clp));
2016 }
2017
2018 /* ARGSUSED */
2019 static int
2020 dcmd_v8type(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
2021 {
2022 char buf[64];
2023 char *bufp = buf;
2024 size_t len = sizeof (buf);
2025
2026 if (obj_jstype(addr, &bufp, &len, NULL) != 0)
2027 return (DCMD_ERR);
2028
2029 mdb_printf("0x%p: %s\n", addr, buf);
2030 return (DCMD_OK);
2031 }
2032
2033 /* ARGSUSED */
2034 static int
2035 dcmd_v8types(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
2036 {
2037 enum_print(v8_types);
2038 return (DCMD_OK);
2039 }
2040
2041 static int
2042 load_current_context(uintptr_t *fpp, uintptr_t *raddrp)
2043 {
2044 mdb_reg_t regfp, regip;
2045
2046 if (mdb_getareg(1, "ebp", ®fp) != 0 ||
2047 mdb_getareg(1, "eip", ®ip) != 0) {
2048 v8_warn("failed to load current context");
2049 return (-1);
2050 }
2051
2052 if (fpp != NULL)
2053 *fpp = (uintptr_t)regfp;
2054
2055 if (raddrp != NULL)
2056 *raddrp = (uintptr_t)regip;
2057
2058 return (0);
2059 }
2060
2061 static int
2062 do_jsframe_special(uintptr_t fptr, uintptr_t raddr)
2063 {
2064 uintptr_t ftype;
2065 const char *ftypename;
2066
2067 /*
2068 * First see if this looks like a native frame rather than a JavaScript
2069 * frame. We check this by asking MDB to print the return address
2070 * symbolically. If that works, we assume this was NOT a V8 frame,
2071 * since those are never in the symbol table.
2072 */
2073 if (mdb_snprintf(NULL, 0, "%A", raddr) > 1) {
2074 mdb_printf("%p %a\n", fptr, raddr);
2075 return (0);
2076 }
2077
2078 /*
2079 * Figure out what kind of frame this is using the same algorithm as
2080 * V8's ComputeType function. First, look for an ArgumentsAdaptorFrame.
2081 */
2082 if (mdb_vread(&ftype, sizeof (ftype), fptr + V8_OFF_FP_CONTEXT) != -1 &&
2083 V8_IS_SMI(ftype) &&
2084 (ftypename = enum_lookup_str(v8_frametypes, V8_SMI_VALUE(ftype),
2085 NULL)) != NULL && strstr(ftypename, "ArgumentsAdaptor") != NULL) {
2086 mdb_printf("%p %a <%s>\n", fptr, raddr, ftypename);
2087 return (0);
2088 }
2089
2090 /*
2091 * Other special frame types are indicated by a marker.
2092 */
2093 if (mdb_vread(&ftype, sizeof (ftype), fptr + V8_OFF_FP_MARKER) != -1 &&
2094 V8_IS_SMI(ftype)) {
2095 ftypename = enum_lookup_str(v8_frametypes, V8_SMI_VALUE(ftype),
2096 NULL);
2097
2098 if (ftypename != NULL)
2099 mdb_printf("%p %a <%s>\n", fptr, raddr, ftypename);
2100 else
2101 mdb_printf("%p %a\n", fptr, raddr);
2102
2103 return (0);
2104 }
2105
2106 return (-1);
2107 }
2108
2109 static int
2110 do_jsframe(uintptr_t fptr, uintptr_t raddr, boolean_t verbose)
2111 {
2112 uintptr_t funcp, funcinfop, tokpos, scriptp, lendsp, ptrp;
2113 uintptr_t ii, nargs;
2114 const char *typename;
2115 char *bufp;
2116 size_t len;
2117 uint8_t type;
2118 char buf[256];
2119
2120 /*
2121 * Check for non-JavaScript frames first.
2122 */
2123 if (do_jsframe_special(fptr, raddr) == 0)
2124 return (DCMD_OK);
2125
2126 /*
2127 * At this point we assume we're looking at a JavaScript frame. As with
2128 * native frames, fish the address out of the parent frame.
2129 */
2130 if (mdb_vread(&funcp, sizeof (funcp),
2131 fptr + V8_OFF_FP_FUNCTION) == -1) {
2132 v8_warn("failed to read stack at %p",
2133 fptr + V8_OFF_FP_FUNCTION);
2134 return (DCMD_ERR);
2135 }
2136
2137 /*
2138 * Check if this thing is really a JSFunction at all. For some frames,
2139 * it's a Code object, presumably indicating some internal frame.
2140 */
2141 v8_silent++;
2142
2143 if (read_typebyte(&type, funcp) != 0 ||
2144 (typename = enum_lookup_str(v8_types, type, NULL)) == NULL) {
2145 v8_silent--;
2146 mdb_printf("%p %a\n", fptr, raddr);
2147 return (DCMD_OK);
2148 }
2149
2150 v8_silent--;
2151
2152 if (strcmp("Code", typename) == 0) {
2153 mdb_printf("%p %a internal (Code: %p)\n", fptr, raddr, funcp);
2154 return (DCMD_OK);
2155 }
2156
2157 if (strcmp("JSFunction", typename) != 0) {
2158 mdb_printf("%p %a unknown (%s: %p)", fptr, raddr, typename,
2159 funcp);
2160 return (DCMD_OK);
2161 }
2162
2163 if (read_heap_ptr(&funcinfop, funcp, V8_OFF_JSFUNCTION_SHARED) != 0)
2164 return (DCMD_ERR);
2165
2166 bufp = buf;
2167 len = sizeof (buf);
2168 if (jsfunc_name(funcinfop, &bufp, &len) != 0)
2169 return (DCMD_ERR);
2170
2171 mdb_printf("%p %a %s (%p)\n", fptr, raddr, buf, funcp);
2172
2173 if (!verbose)
2174 return (DCMD_OK);
2175
2176 /*
2177 * Although the token position is technically an SMI, we're going to
2178 * byte-compare it to other SMI values so we don't want decode it here.
2179 */
2180 if (read_heap_ptr(&tokpos, funcinfop,
2181 V8_OFF_SHAREDFUNCTIONINFO_FUNCTION_TOKEN_POSITION) != 0)
2182 return (DCMD_ERR);
2183
2184 if (read_heap_ptr(&scriptp, funcinfop,
2185 V8_OFF_SHAREDFUNCTIONINFO_SCRIPT) != 0)
2186 return (DCMD_ERR);
2187
2188 if (read_heap_ptr(&ptrp, scriptp, V8_OFF_SCRIPT_NAME) != 0)
2189 return (DCMD_ERR);
2190
2191 bufp = buf;
2192 len = sizeof (buf);
2193 (void) jsstr_print(ptrp, B_FALSE, &bufp, &len);
2194
2195 (void) mdb_inc_indent(4);
2196 mdb_printf("file: %s\n", buf);
2197
2198 if (read_heap_ptr(&lendsp, scriptp, V8_OFF_SCRIPT_LINE_ENDS) != 0)
2199 return (DCMD_ERR);
2200
2201 (void) jsfunc_lineno(lendsp, tokpos, buf, sizeof (buf));
2202
2203 mdb_printf("posn: %s\n", buf);
2204
2205 if (read_heap_smi(&nargs, funcinfop,
2206 V8_OFF_SHAREDFUNCTIONINFO_LENGTH) == 0) {
2207 for (ii = 0; ii < nargs; ii++) {
2208 uintptr_t argptr;
2209
2210 if (mdb_vread(&argptr, sizeof (argptr),
2211 fptr + V8_OFF_FP_ARGS + (nargs - ii - 1) *
2212 sizeof (uintptr_t)) == -1)
2213 continue;
2214
2215 bufp = buf;
2216 len = sizeof (buf);
2217 (void) obj_jstype(argptr, &bufp, &len, NULL);
2218
2219 mdb_printf("arg%d: %p (%s)\n", (ii + 1), argptr, buf);
2220 }
2221 }
2222
2223 (void) mdb_dec_indent(4);
2224
2225 return (DCMD_OK);
2226 }
2227
2228 typedef struct findjsobjects_prop {
2229 struct findjsobjects_prop *fjsp_next;
2230 char fjsp_desc[1];
2231 } findjsobjects_prop_t;
2232
2233 typedef struct findjsobjects_instance {
2234 uintptr_t fjsi_addr;
2235 struct findjsobjects_instance *fjsi_next;
2236 } findjsobjects_instance_t;
2237
2238 typedef struct findjsobjects_obj {
2239 findjsobjects_prop_t *fjso_props;
2240 findjsobjects_prop_t *fjso_last;
2241 int fjso_nprops;
2242 findjsobjects_instance_t fjso_instances;
2243 int fjso_ninstances;
2244 avl_node_t fjso_node;
2245 struct findjsobjects_obj *fjso_next;
2246 } findjsobjects_obj_t;
2247
2248 typedef struct findjsobjects_stats {
2249 int fjss_heapobjs;
2250 int fjss_jsobjs;
2251 int fjss_objects;
2252 int fjss_uniques;
2253 } findjsobjects_stats_t;
2254
2255 typedef struct findjsobjects_state {
2256 uintptr_t fjs_addr;
2257 uintptr_t fjs_size;
2258 boolean_t fjs_verbose;
2259 boolean_t fjs_brk;
2260 boolean_t fjs_initialized;
2261 uintptr_t fjs_referent;
2262 boolean_t fjs_referred;
2263 avl_tree_t fjs_tree;
2264 findjsobjects_obj_t *fjs_current;
2265 findjsobjects_obj_t *fjs_objects;
2266 findjsobjects_stats_t fjs_stats;
2267 } findjsobjects_state_t;
2268
2269 findjsobjects_obj_t *
2270 findjsobjects_alloc(uintptr_t addr)
2271 {
2272 findjsobjects_obj_t *obj;
2273
2274 obj = mdb_zalloc(sizeof (findjsobjects_obj_t), UM_SLEEP);
2275 obj->fjso_instances.fjsi_addr = addr;
2276 obj->fjso_ninstances = 1;
2277
2278 return (obj);
2279 }
2280
2281 void
2282 findjsobjects_free(findjsobjects_obj_t *obj)
2283 {
2284 findjsobjects_prop_t *prop, *next;
2285
2286 for (prop = obj->fjso_props; prop != NULL; prop = next) {
2287 next = prop->fjsp_next;
2288 mdb_free(prop, sizeof (findjsobjects_prop_t) +
2289 strlen(prop->fjsp_desc));
2290 }
2291
2292 mdb_free(obj, sizeof (findjsobjects_obj_t));
2293 }
2294
2295 int
2296 findjsobjects_cmp(findjsobjects_obj_t *lhs, findjsobjects_obj_t *rhs)
2297 {
2298 findjsobjects_prop_t *lprop, *rprop;
2299 int rv;
2300
2301 lprop = lhs->fjso_props;
2302 rprop = rhs->fjso_props;
2303
2304 for (;;) {
2305 if (lprop == NULL || rprop == NULL)
2306 return (lprop != NULL ? 1 : rprop != NULL ? -1 : 0);
2307
2308 if ((rv = strcmp(lprop->fjsp_desc, rprop->fjsp_desc)) != 0)
2309 return (rv > 0 ? 1 : -1);
2310
2311 lprop = lprop->fjsp_next;
2312 rprop = rprop->fjsp_next;
2313 }
2314 }
2315
2316 int
2317 findjsobjects_cmp_ninstances(const void *l, const void *r)
2318 {
2319 findjsobjects_obj_t *lhs = *((findjsobjects_obj_t **)l);
2320 findjsobjects_obj_t *rhs = *((findjsobjects_obj_t **)r);
2321
2322 if (lhs->fjso_ninstances < rhs->fjso_ninstances)
2323 return (-1);
2324
2325 if (lhs->fjso_ninstances > rhs->fjso_ninstances)
2326 return (1);
2327
2328 if (lhs->fjso_nprops < rhs->fjso_nprops)
2329 return (-1);
2330
2331 if (lhs->fjso_nprops > rhs->fjso_nprops)
2332 return (1);
2333
2334 return (0);
2335 }
2336
2337 /*ARGSUSED*/
2338 int
2339 findjsobjects_prop(const char *desc, uintptr_t val, void *arg)
2340 {
2341 findjsobjects_state_t *fjs = arg;
2342 findjsobjects_obj_t *current = fjs->fjs_current;
2343 findjsobjects_prop_t *prop;
2344
2345 if (desc == NULL)
2346 desc = "<unknown>";
2347
2348 prop = mdb_zalloc(sizeof (findjsobjects_prop_t) +
2349 strlen(desc), UM_SLEEP);
2350
2351 strcpy(prop->fjsp_desc, desc);
2352
2353 if (current->fjso_last != NULL) {
2354 current->fjso_last->fjsp_next = prop;
2355 } else {
2356 current->fjso_props = prop;
2357 }
2358
2359 current->fjso_last = prop;
2360 current->fjso_nprops++;
2361
2362 return (0);
2363 }
2364
2365 int
2366 findjsobjects_range(findjsobjects_state_t *fjs, uintptr_t addr, uintptr_t size)
2367 {
2368 uintptr_t limit;
2369 findjsobjects_stats_t *stats = &fjs->fjs_stats;
2370 uint8_t type;
2371 int jsobject = V8_TYPE_JSOBJECT;
2372
2373
2374 for (limit = addr + size; addr < limit; addr++) {
2375 findjsobjects_instance_t *inst;
2376 findjsobjects_obj_t *obj;
2377 avl_index_t where;
2378
2379 if (V8_IS_SMI(addr))
2380 continue;
2381
2382 if (!V8_IS_HEAPOBJECT(addr))
2383 continue;
2384
2385 stats->fjss_heapobjs++;
2386
2387 if (read_typebyte(&type, addr) == -1)
2388 continue;
2389
2390 if (type != jsobject)
2391 continue;
2392
2393 stats->fjss_jsobjs++;
2394
2395 fjs->fjs_current = findjsobjects_alloc(addr);
2396
2397 if (jsobj_properties(addr, findjsobjects_prop, fjs) != 0) {
2398 findjsobjects_free(fjs->fjs_current);
2399 fjs->fjs_current = NULL;
2400 continue;
2401 }
2402
2403 /*
2404 * Now determine if we already have an object matching our
2405 * properties. If we don't, we'll add our new object; if we
2406 * do we'll merely enqeuue our instance.
2407 */
2408 obj = avl_find(&fjs->fjs_tree, fjs->fjs_current, &where);
2409 stats->fjss_objects++;
2410
2411 if (obj == NULL) {
2412 avl_add(&fjs->fjs_tree, fjs->fjs_current);
2413 fjs->fjs_current->fjso_next = fjs->fjs_objects;
2414 fjs->fjs_objects = fjs->fjs_current;
2415 fjs->fjs_current = NULL;
2416 stats->fjss_uniques++;
2417 continue;
2418 }
2419
2420 findjsobjects_free(fjs->fjs_current);
2421 fjs->fjs_current = NULL;
2422
2423 inst = mdb_alloc(sizeof (findjsobjects_instance_t), UM_SLEEP);
2424 inst->fjsi_addr = addr;
2425 inst->fjsi_next = obj->fjso_instances.fjsi_next;
2426 obj->fjso_instances.fjsi_next = inst;
2427 obj->fjso_ninstances++;
2428 }
2429
2430 return (0);
2431 }
2432
2433 static int
2434 findjsobjects_mapping(findjsobjects_state_t *fjs, const prmap_t *pmp,
2435 const char *name)
2436 {
2437 if (name != NULL && !(fjs->fjs_brk && (pmp->pr_mflags & MA_BREAK)))
2438 return (0);
2439
2440 if (fjs->fjs_addr != NULL && (fjs->fjs_addr < pmp->pr_vaddr ||
2441 fjs->fjs_addr >= pmp->pr_vaddr + pmp->pr_size))
2442 return (0);
2443
2444 return (findjsobjects_range(fjs, pmp->pr_vaddr, pmp->pr_size));
2445 }
2446
2447 static int
2448 findjsobjects_references_prop(const char *desc, uintptr_t val, void *arg)
2449 {
2450 findjsobjects_state_t *fjs = arg;
2451
2452 if (val == fjs->fjs_referent) {
2453 mdb_printf("%p referred to by %p.%s\n", fjs->fjs_referent,
2454 fjs->fjs_addr, desc);
2455 fjs->fjs_referred = B_TRUE;
2456 return (0);
2457 }
2458
2459 return (0);
2460 }
2461
2462 static void
2463 findjsobjects_references(findjsobjects_state_t *fjs, uintptr_t addr)
2464 {
2465 findjsobjects_instance_t *inst;
2466 findjsobjects_obj_t *obj;
2467
2468 fjs->fjs_referent = addr;
2469 fjs->fjs_referred = B_FALSE;
2470
2471 v8_silent++;
2472
2473 for (obj = fjs->fjs_objects; obj != NULL; obj = obj->fjso_next) {
2474 for (inst = &obj->fjso_instances;
2475 inst != NULL; inst = inst->fjsi_next) {
2476 fjs->fjs_addr = inst->fjsi_addr;
2477 (void) jsobj_properties(inst->fjsi_addr,
2478 findjsobjects_references_prop, fjs);
2479 }
2480 }
2481
2482 v8_silent--;
2483
2484 if (!fjs->fjs_referred)
2485 mdb_printf("%p is not referred to by a known object.\n", addr);
2486
2487 fjs->fjs_addr = NULL;
2488 }
2489
2490 static char *
2491 findjsobjects_constructor(findjsobjects_obj_t *obj)
2492 {
2493 static char buf[80];
2494 char *bufp = buf, *rval = NULL;
2495 unsigned int len = sizeof (buf);
2496 uintptr_t map, funcinfop;
2497 uintptr_t addr = obj->fjso_instances.fjsi_addr;
2498 uint8_t type;
2499
2500 v8_silent++;
2501
2502 if (read_heap_ptr(&map, addr, V8_OFF_HEAPOBJECT_MAP) != 0 ||
2503 read_heap_ptr(&addr, map, V8_OFF_MAP_CONSTRUCTOR) != 0)
2504 goto out;
2505
2506 if (read_typebyte(&type, addr) != 0)
2507 goto out;
2508
2509 if (strcmp(enum_lookup_str(v8_types, type, ""), "JSFunction") != 0)
2510 goto out;
2511
2512 if (read_heap_ptr(&funcinfop, addr, V8_OFF_JSFUNCTION_SHARED) != 0)
2513 goto out;
2514
2515 if (jsfunc_name(funcinfop, &bufp, &len) != 0)
2516 goto out;
2517
2518 rval = buf;
2519 out:
2520 v8_silent--;
2521
2522 return (rval);
2523 }
2524
2525 static void
2526 findjsobjects_print(findjsobjects_obj_t *obj)
2527 {
2528 int col = 17 + (sizeof (uintptr_t) * 2) + strlen("..."), len;
2529 uintptr_t addr = obj->fjso_instances.fjsi_addr;
2530 char *buf = findjsobjects_constructor(obj);
2531 findjsobjects_prop_t *prop;
2532
2533 mdb_printf("%?p %8d %6d ",
2534 addr, obj->fjso_ninstances, obj->fjso_nprops);
2535
2536 if (buf != NULL) {
2537 mdb_printf("%s: ", buf);
2538 col += strlen(buf) + 2;
2539 }
2540
2541 for (prop = obj->fjso_props; prop != NULL; prop = prop->fjsp_next) {
2542 if (col + (len = strlen(prop->fjsp_desc) + 2) < 80) {
2543 mdb_printf("%s%s", prop->fjsp_desc,
2544 prop->fjsp_next != NULL ? ", " : "");
2545 col += len;
2546 } else {
2547 mdb_printf("...");
2548 break;
2549 }
2550 }
2551
2552 mdb_printf("\n", col);
2553 }
2554
2555 static void
2556 dcmd_findjsobjects_help(void)
2557 {
2558 mdb_printf("%s\n\n",
2559 "Finds all JavaScript objects in the V8 heap via brute force iteration over\n"
2560 "all mapped anonymous memory. (This can take up to several minutes on large\n"
2561 "dumps.) The output consists of representative objects, the number of\n"
2562 "instances of that object and the number of properties on the object --\n"
2563 "followed by the constructor and first few properties of the objects. Once\n"
2564 "run, subsequent calls to ::findjsobjects use cached data. If provided an\n"
2565 "address (and in the absence of -r, described below), ::findjsobjects treats\n"
2566 "the address as that of a representative object, and emits all instances of\n"
2567 "that object (that is, all objects that have a matching property signature).");
2568
2569 mdb_dec_indent(2);
2570 mdb_printf("%<b>OPTIONS%</b>\n");
2571 mdb_inc_indent(2);
2572
2573 mdb_printf("%s\n",
2574 " -b Include the heap denoted by the brk(2) (normally excluded)\n"
2575 " -c cons Display representative objects with the specified constructor\n"
2576 " -p prop Display representative objects that have the specified property\n"
2577 " -r Find references to the specified object\n"
2578 " -v Provide verbose statistics\n");
2579 }
2580
2581 static int
2582 dcmd_findjsobjects(uintptr_t addr,
2583 uint_t flags, int argc, const mdb_arg_t *argv)
2584 {
2585 static findjsobjects_state_t fjs;
2586 static findjsobjects_stats_t *stats = &fjs.fjs_stats;
2587 findjsobjects_obj_t *obj;
2588 findjsobjects_prop_t *prop;
2589 struct ps_prochandle *Pr;
2590 boolean_t references = B_FALSE;
2591 const char *propname = NULL;
2592 const char *constructor = NULL;
2593
2594 fjs.fjs_verbose = B_FALSE;
2595 fjs.fjs_brk = B_FALSE;
2596
2597 if (mdb_getopts(argc, argv,
2598 'b', MDB_OPT_SETBITS, B_TRUE, &fjs.fjs_brk,
2599 'c', MDB_OPT_STR, &constructor,
2600 'p', MDB_OPT_STR, &propname,
2601 'r', MDB_OPT_SETBITS, B_TRUE, &references,
2602 'v', MDB_OPT_SETBITS, B_TRUE, &fjs.fjs_verbose,
2603 NULL) != argc)
2604 return (DCMD_USAGE);
2605
2606 if (!fjs.fjs_initialized) {
2607 avl_create(&fjs.fjs_tree,
2608 (int(*)(const void *, const void *))findjsobjects_cmp,
2609 sizeof (findjsobjects_obj_t),
2610 offsetof(findjsobjects_obj_t, fjso_node));
2611 fjs.fjs_initialized = B_TRUE;
2612 }
2613
2614 if (avl_is_empty(&fjs.fjs_tree)) {
2615 findjsobjects_obj_t **sorted;
2616 int nobjs, i;
2617 hrtime_t start = gethrtime();
2618
2619 if (mdb_get_xdata("pshandle", &Pr, sizeof (Pr)) == -1) {
2620 mdb_warn("couldn't read pshandle xdata");
2621 return (DCMD_ERR);
2622 }
2623
2624 v8_silent++;
2625
2626 if (Pmapping_iter(Pr,
2627 (proc_map_f *)findjsobjects_mapping, &fjs) != 0) {
2628 v8_silent--;
2629 return (DCMD_ERR);
2630 }
2631
2632 nobjs = avl_numnodes(&fjs.fjs_tree);
2633
2634 /*
2635 * We have the objects -- now sort them.
2636 */
2637 sorted = mdb_alloc(nobjs * sizeof (void *), UM_GC);
2638
2639 for (obj = fjs.fjs_objects, i = 0; obj != NULL;
2640 obj = obj->fjso_next, i++) {
2641 sorted[i] = obj;
2642 }
2643
2644 qsort(sorted, avl_numnodes(&fjs.fjs_tree), sizeof (void *),
2645 findjsobjects_cmp_ninstances);
2646
2647 for (i = 1, fjs.fjs_objects = sorted[0]; i < nobjs; i++)
2648 sorted[i - 1]->fjso_next = sorted[i];
2649
2650 sorted[nobjs - 1]->fjso_next = NULL;
2651
2652 v8_silent--;
2653
2654 if (fjs.fjs_verbose) {
2655 const char *f = "findjsobjects: %30s => %d\n";
2656 int elapsed = (int)((gethrtime() - start) / NANOSEC);
2657
2658 mdb_printf(f, "elapsed time (seconds)", elapsed);
2659 mdb_printf(f, "heap objects", stats->fjss_heapobjs);
2660 mdb_printf(f, "JavaScript objects", stats->fjss_jsobjs);
2661 mdb_printf(f, "processed objects", stats->fjss_objects);
2662 mdb_printf(f, "unique objects", stats->fjss_uniques);
2663 }
2664 }
2665
2666 if (propname != NULL) {
2667 if (flags & DCMD_ADDRSPEC) {
2668 mdb_warn("cannot specify an object when "
2669 "specifying a property name\n");
2670 return (DCMD_ERR);
2671 }
2672
2673 if (constructor != NULL) {
2674 mdb_warn("cannot specify both a property name "
2675 "and a constructor\n");
2676 return (DCMD_ERR);
2677 }
2678
2679 for (obj = fjs.fjs_objects; obj != NULL; obj = obj->fjso_next) {
2680 for (prop = obj->fjso_props; prop != NULL;
2681 prop = prop->fjsp_next) {
2682 if (strcmp(prop->fjsp_desc, propname) == 0)
2683 break;
2684 }
2685
2686 if (prop == NULL)
2687 continue;
2688
2689 mdb_printf("%p\n", obj->fjso_instances.fjsi_addr);
2690 }
2691
2692 return (DCMD_OK);
2693 }
2694
2695 if (constructor != NULL) {
2696 if (flags & DCMD_ADDRSPEC) {
2697 mdb_warn("cannot specify an object when "
2698 "specifying a constructor\n");
2699 return (DCMD_ERR);
2700 }
2701
2702 for (obj = fjs.fjs_objects; obj != NULL; obj = obj->fjso_next) {
2703 char *cons = findjsobjects_constructor(obj);
2704
2705 if (cons == NULL || strcmp(constructor, cons) != 0)
2706 continue;
2707
2708 mdb_printf("%p\n", obj->fjso_instances.fjsi_addr);
2709 }
2710
2711 return (DCMD_OK);
2712 }
2713
2714 if (references && !(flags & DCMD_ADDRSPEC)) {
2715 mdb_warn("must specify an object to find references\n");
2716 return (DCMD_ERR);
2717 }
2718
2719 if (flags & DCMD_ADDRSPEC) {
2720 /*
2721 * If we've been passed an address, we're either looking for
2722 * similar objects or for references (if -r has been set).
2723 */
2724 if (references) {
2725 findjsobjects_references(&fjs, addr);
2726 return (DCMD_OK);
2727 }
2728
2729 for (obj = fjs.fjs_objects; obj != NULL; obj = obj->fjso_next) {
2730 findjsobjects_instance_t *inst, *h;
2731
2732 h = &obj->fjso_instances;
2733
2734 for (inst = h; inst != NULL; inst = inst->fjsi_next) {
2735 if (inst->fjsi_addr == addr)
2736 break;
2737 }
2738
2739 if (inst == NULL)
2740 continue;
2741
2742 for (inst = h; inst != NULL; inst = inst->fjsi_next)
2743 mdb_printf("%p\n", inst->fjsi_addr);
2744
2745 return (DCMD_OK);
2746 }
2747
2748 mdb_warn("%p is not a valid object\n", addr);
2749 return (DCMD_ERR);
2750 }
2751
2752 mdb_printf("%-?s %8s %6s %s\n", "OBJECT",
2753 "#OBJECTS", "#PROPS", "CONSTRUCTOR: PROPS");
2754
2755 for (obj = fjs.fjs_objects; obj != NULL; obj = obj->fjso_next)
2756 findjsobjects_print(obj);
2757
2758 return (DCMD_OK);
2759 }
2760
2761 /* ARGSUSED */
2762 static int
2763 dcmd_jsframe(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
2764 {
2765 uintptr_t fptr, raddr;
2766 boolean_t opt_v = B_FALSE, opt_i = B_FALSE;
2767
2768 if (mdb_getopts(argc, argv, 'v', MDB_OPT_SETBITS, B_TRUE, &opt_v,
2769 'i', MDB_OPT_SETBITS, B_TRUE, &opt_i, NULL) != argc)
2770 return (DCMD_USAGE);
2771
2772 /*
2773 * As with $C, we assume we are given a *pointer* to the frame pointer
2774 * for a frame, rather than the actual frame pointer for the frame of
2775 * interest. This is needed to show the instruction pointer, which is
2776 * actually stored with the next frame. For debugging, this can be
2777 * overridden with the "-i" option (for "immediate").
2778 */
2779 if (opt_i)
2780 return (do_jsframe(addr, 0, opt_v));
2781
2782 if (mdb_vread(&raddr, sizeof (raddr),
2783 addr + sizeof (uintptr_t)) == -1) {
2784 mdb_warn("failed to read return address from %p",
2785 addr + sizeof (uintptr_t));
2786 return (DCMD_ERR);
2787 }
2788
2789 if (mdb_vread(&fptr, sizeof (fptr), addr) == -1) {
2790 mdb_warn("failed to read frame pointer from %p", addr);
2791 return (DCMD_ERR);
2792 }
2793
2794 if (fptr == NULL)
2795 return (DCMD_OK);
2796
2797 return (do_jsframe(fptr, raddr, opt_v));
2798 }
2799
2800 /* ARGSUSED */
2801 static int
2802 dcmd_jsprint(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
2803 {
2804 char *buf, *bufp;
2805 size_t bufsz = 262144, len = bufsz;
2806 jsobj_print_t jsop;
2807 int rv;
2808
2809 bzero(&jsop, sizeof (jsop));
2810 jsop.jsop_depth = 2;
2811 jsop.jsop_printaddr = B_FALSE;
2812
2813 if (mdb_getopts(argc, argv,
2814 'a', MDB_OPT_SETBITS, B_TRUE, &jsop.jsop_printaddr,
2815 'd', MDB_OPT_UINT64, &jsop.jsop_depth, NULL) != argc)
2816 return (DCMD_USAGE);
2817
2818 if ((buf = bufp = mdb_zalloc(bufsz, UM_NOSLEEP)) == NULL)
2819 return (DCMD_ERR);
2820
2821 jsop.jsop_bufp = &bufp;
2822 jsop.jsop_lenp = &len;
2823
2824 rv = jsobj_print(addr, &jsop);
2825 (void) mdb_printf("%s\n", buf);
2826 mdb_free(buf, bufsz);
2827 return (rv == 0 ? DCMD_OK : DCMD_ERR);
2828 }
2829
2830 /* ARGSUSED */
2831 static int
2832 dcmd_v8field(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
2833 {
2834 v8_class_t *clp;
2835 v8_field_t *flp;
2836 const char *klass, *field;
2837 uintptr_t offset;
2838
2839 /*
2840 * We may be invoked with either two arguments (class and field name) or
2841 * three (an offset to save).
2842 */
2843 if (argc != 2 && argc != 3)
2844 return (DCMD_USAGE);
2845
2846 if (argv[0].a_type != MDB_TYPE_STRING ||
2847 argv[1].a_type != MDB_TYPE_STRING)
2848 return (DCMD_USAGE);
2849
2850 klass = argv[0].a_un.a_str;
2851 field = argv[1].a_un.a_str;
2852
2853 if (argc == 3) {
2854 if (argv[2].a_type != MDB_TYPE_STRING)
2855 return (DCMD_USAGE);
2856
2857 offset = mdb_strtoull(argv[2].a_un.a_str);
2858 }
2859
2860 for (clp = v8_classes; clp != NULL; clp = clp->v8c_next)
2861 if (strcmp(clp->v8c_name, klass) == 0)
2862 break;
2863
2864 if (clp == NULL) {
2865 (void) mdb_printf("error: no such class: \"%s\"", klass);
2866 return (DCMD_ERR);
2867 }
2868
2869 for (flp = clp->v8c_fields; flp != NULL; flp = flp->v8f_next)
2870 if (strcmp(field, flp->v8f_name) == 0)
2871 break;
2872
2873 if (flp == NULL) {
2874 if (argc == 2) {
2875 mdb_printf("error: no such field in class \"%s\": "
2876 "\"%s\"", klass, field);
2877 return (DCMD_ERR);
2878 }
2879
2880 flp = conf_field_create(clp, field, offset);
2881 if (flp == NULL) {
2882 mdb_warn("failed to create field");
2883 return (DCMD_ERR);
2884 }
2885 } else if (argc == 3) {
2886 flp->v8f_offset = offset;
2887 }
2888
2889 mdb_printf("%s::%s at offset 0x%x\n", klass, field, flp->v8f_offset);
2890 return (DCMD_OK);
2891 }
2892
2893 /* ARGSUSED */
2894 static int
2895 dcmd_v8array(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
2896 {
2897 uint8_t type;
2898 uintptr_t *array;
2899 size_t ii, len;
2900
2901 if (read_typebyte(&type, addr) != 0)
2902 return (DCMD_ERR);
2903
2904 if (type != V8_TYPE_FIXEDARRAY) {
2905 mdb_warn("%p is not an instance of FixedArray\n", addr);
2906 return (DCMD_ERR);
2907 }
2908
2909 if (read_heap_array(addr, &array, &len, UM_GC) != 0)
2910 return (DCMD_ERR);
2911
2912 for (ii = 0; ii < len; ii++)
2913 mdb_printf("%p\n", array[ii]);
2914
2915 return (DCMD_OK);
2916 }
2917
2918 /* ARGSUSED */
2919 static int
2920 dcmd_jsstack(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
2921 {
2922 uintptr_t raddr;
2923 boolean_t opt_v;
2924
2925 if (mdb_getopts(argc, argv, 'v', MDB_OPT_SETBITS, B_TRUE, &opt_v,
2926 NULL) != argc)
2927 return (DCMD_USAGE);
2928
2929 /*
2930 * The "::jsframe" walker iterates the valid frame pointers, but the
2931 * "::jsframe" dcmd looks at the frame after the one it was given, so we
2932 * have to explicitly examine the top frame here.
2933 */
2934 if (!(flags & DCMD_ADDRSPEC)) {
2935 if (load_current_context(&addr, &raddr) != 0 ||
2936 do_jsframe(addr, raddr, opt_v) != 0)
2937 return (DCMD_ERR);
2938 }
2939
2940 if (mdb_pwalk_dcmd("jsframe", "jsframe", argc, argv, addr) == -1)
2941 return (DCMD_ERR);
2942
2943 return (DCMD_OK);
2944 }
2945
2946 /* ARGSUSED */
2947 static int
2948 dcmd_v8str(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
2949 {
2950 boolean_t opt_v = B_FALSE;
2951 char buf[256];
2952 char *bufp;
2953 size_t len;
2954
2955 if (mdb_getopts(argc, argv, 'v', MDB_OPT_SETBITS, B_TRUE, &opt_v,
2956 NULL) != argc)
2957 return (DCMD_USAGE);
2958
2959 bufp = buf;
2960 len = sizeof (buf);
2961 if (jsstr_print(addr, opt_v, &bufp, &len) != 0)
2962 return (DCMD_ERR);
2963
2964 mdb_printf("%s\n", buf);
2965 return (DCMD_OK);
2966 }
2967
2968 static void
2969 dcmd_v8load_help(void)
2970 {
2971 v8_cfg_t *cfp, **cfgpp;
2972
2973 mdb_printf(
2974 "To traverse in-memory V8 structures, the V8 dmod requires\n"
2975 "configuration that describes the layout of various V8 structures\n"
2976 "in memory. Normally, this information is pulled from metadata\n"
2977 "in the target binary. However, it's possible to use the module\n"
2978 "with a binary not built with metadata by loading one of the\n"
2979 "canned configurations.\n\n");
2980
2981 mdb_printf("Available configurations:\n");
2982
2983 (void) mdb_inc_indent(4);
2984
2985 for (cfgpp = v8_cfgs; *cfgpp != NULL; cfgpp++) {
2986 cfp = *cfgpp;
2987 mdb_printf("%-10s %s\n", cfp->v8cfg_name, cfp->v8cfg_label);
2988 }
2989
2990 (void) mdb_dec_indent(4);
2991 }
2992
2993 /* ARGSUSED */
2994 static int
2995 dcmd_v8load(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
2996 {
2997 v8_cfg_t *cfgp, **cfgpp;
2998
2999 if (v8_classes != NULL) {
3000 mdb_warn("v8 module already configured\n");
3001 return (DCMD_ERR);
3002 }
3003
3004 if (argc < 1 || argv->a_type != MDB_TYPE_STRING)
3005 return (DCMD_USAGE);
3006
3007 for (cfgpp = v8_cfgs; *cfgpp != NULL; cfgpp++) {
3008 cfgp = *cfgpp;
3009 if (strcmp(argv->a_un.a_str, cfgp->v8cfg_name) == 0)
3010 break;
3011 }
3012
3013 if (cfgp->v8cfg_name == NULL) {
3014 mdb_warn("unknown configuration: \"%s\"\n", argv->a_un.a_str);
3015 return (DCMD_ERR);
3016 }
3017
3018 if (autoconfigure(cfgp) == -1) {
3019 mdb_warn("autoconfigure failed\n");
3020 return (DCMD_ERR);
3021 }
3022
3023 mdb_printf("V8 dmod configured based on %s\n", cfgp->v8cfg_name);
3024 return (DCMD_OK);
3025 }
3026
3027 static int
3028 walk_jsframes_init(mdb_walk_state_t *wsp)
3029 {
3030 if (wsp->walk_addr != NULL)
3031 return (WALK_NEXT);
3032
3033 if (load_current_context(&wsp->walk_addr, NULL) != 0)
3034 return (WALK_ERR);
3035
3036 return (WALK_NEXT);
3037 }
3038
3039 static int
3040 walk_jsframes_step(mdb_walk_state_t *wsp)
3041 {
3042 uintptr_t addr, next;
3043 int rv;
3044
3045 addr = wsp->walk_addr;
3046 rv = wsp->walk_callback(wsp->walk_addr, NULL, wsp->walk_cbdata);
3047
3048 if (rv != WALK_NEXT)
3049 return (rv);
3050
3051 if (mdb_vread(&next, sizeof (next), addr) == -1)
3052 return (WALK_ERR);
3053
3054 if (next == NULL)
3055 return (WALK_DONE);
3056
3057 wsp->walk_addr = next;
3058 return (WALK_NEXT);
3059 }
3060
3061 /*
3062 * MDB linkage
3063 */
3064
3065 static const mdb_dcmd_t v8_mdb_dcmds[] = {
3066 /*
3067 * Commands to inspect JavaScript-level state
3068 */
3069 { "jsframe", ":[-v]", "summarize a JavaScript stack frame",
3070 dcmd_jsframe },
3071 { "jsprint", ":[-a] [-d depth]", "print a JavaScript object",
3072 dcmd_jsprint },
3073 { "jsstack", "[-v]", "print a JavaScript stacktrace",
3074 dcmd_jsstack },
3075 { "findjsobjects", "?[-vb] [-r | -c cons | -p prop]", "find JavaScript "
3076 "objects", dcmd_findjsobjects, dcmd_findjsobjects_help },
3077
3078 /*
3079 * Commands to inspect V8-level state
3080 */
3081 { "v8array", ":", "print elements of a V8 FixedArray",
3082 dcmd_v8array },
3083 { "v8classes", NULL, "list known V8 heap object C++ classes",
3084 dcmd_v8classes },
3085 { "v8code", ":[-d]", "print information about a V8 Code object",
3086 dcmd_v8code },
3087 { "v8field", "classname fieldname offset",
3088 "manually add a field to a given class", dcmd_v8field },
3089 { "v8function", ":[-d]", "print JSFunction object details",
3090 dcmd_v8function },
3091 { "v8load", "version", "load canned config for a specific V8 version",
3092 dcmd_v8load, dcmd_v8load_help },
3093 { "v8frametypes", NULL, "list known V8 frame types",
3094 dcmd_v8frametypes },
3095 { "v8print", ":[class]", "print a V8 heap object",
3096 dcmd_v8print, dcmd_v8print_help },
3097 { "v8str", ":[-v]", "print the contents of a V8 string",
3098 dcmd_v8str },
3099 { "v8type", ":", "print the type of a V8 heap object",
3100 dcmd_v8type },
3101 { "v8types", NULL, "list known V8 heap object types",
3102 dcmd_v8types },
3103
3104 { NULL }
3105 };
3106
3107 static const mdb_walker_t v8_mdb_walkers[] = {
3108 { "jsframe", "walk V8 JavaScript stack frames",
3109 walk_jsframes_init, walk_jsframes_step },
3110 { NULL }
3111 };
3112
3113 static mdb_modinfo_t v8_mdb = { MDB_API_VERSION, v8_mdb_dcmds, v8_mdb_walkers };
3114
3115 static void
3116 configure(void)
3117 {
3118 uintptr_t v8major, v8minor, v8build, v8patch;
3119 GElf_Sym sym;
3120
3121 if (mdb_readsym(&v8major, sizeof (v8major),
3122 "_ZN2v88internal7Version6major_E") == -1 ||
3123 mdb_readsym(&v8minor, sizeof (v8minor),
3124 "_ZN2v88internal7Version6minor_E") == -1 ||
3125 mdb_readsym(&v8build, sizeof (v8build),
3126 "_ZN2v88internal7Version6build_E") == -1 ||
3127 mdb_readsym(&v8patch, sizeof (v8patch),
3128 "_ZN2v88internal7Version6patch_E") == -1) {
3129 mdb_warn("failed to determine V8 version");
3130 return;
3131 }
3132
3133 mdb_printf("V8 version: %d.%d.%d.%d\n", v8major, v8minor, v8build,
3134 v8patch);
3135
3136 /*
3137 * First look for debug metadata embedded within the binary, which may
3138 * be present in recent V8 versions built with postmortem metadata.
3139 */
3140 if (mdb_lookup_by_name("v8dbg_SmiTag", &sym) == 0) {
3141 if (autoconfigure(&v8_cfg_target) != 0) {
3142 mdb_warn("failed to autoconfigure from target; "
3143 "commands may have incorrect results!\n");
3144 } else {
3145 mdb_printf("Autoconfigured V8 support from target\n");
3146 }
3147
3148 return;
3149 }
3150
3151 if (v8major == 3 && v8minor == 1 && v8build == 8 &&
3152 autoconfigure(&v8_cfg_04) == 0) {
3153 mdb_printf("Configured V8 support based on node v0.4\n");
3154 return;
3155 }
3156
3157 if (v8major == 3 && v8minor == 6 && v8build == 6 &&
3158 autoconfigure(&v8_cfg_06) == 0) {
3159 mdb_printf("Configured V8 support based on node v0.6\n");
3160 return;
3161 }
3162
3163 mdb_printf("mdb_v8: target has no debug metadata and no existing "
3164 "config found\n");
3165 }
3166
3167 static void
3168 enable_demangling(void)
3169 {
3170 const char *symname = "_ZN2v88internal7Version6major_E";
3171 GElf_Sym sym;
3172 char buf[64];
3173
3174 /*
3175 * Try to determine whether C++ symbol demangling has been enabled. If
3176 * not, enable it.
3177 */
3178 if (mdb_lookup_by_name("_ZN2v88internal7Version6major_E", &sym) != 0)
3179 return;
3180
3181 (void) mdb_snprintf(buf, sizeof (buf), "%a", sym.st_value);
3182 if (strstr(buf, symname) != NULL)
3183 (void) mdb_eval("$G");
3184 }
3185
3186 const mdb_modinfo_t *
3187 _mdb_init(void)
3188 {
3189 configure();
3190 enable_demangling();
3191 return (&v8_mdb);
3192 }