1 /* -*- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
2 *
3 * ***** BEGIN LICENSE BLOCK *****
4 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
5 *
6 * The contents of this file are subject to the Mozilla Public License Version
7 * 1.1 (the "License"); you may not use this file except in compliance with
8 * the License. You may obtain a copy of the License at
9 * http://www.mozilla.org/MPL/
10 *
11 * Software distributed under the License is distributed on an "AS IS" basis,
12 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
13 * for the specific language governing rights and limitations under the
14 * License.
15 *
16 * The Original Code is Mozilla Communicator client code, released
17 * March 31, 1998.
18 *
19 * The Initial Developer of the Original Code is
20 * Netscape Communications Corporation.
21 * Portions created by the Initial Developer are Copyright (C) 1998
22 * the Initial Developer. All Rights Reserved.
23 *
24 * Contributor(s):
25 *
26 * Alternatively, the contents of this file may be used under the terms of
27 * either of the GNU General Public License Version 2 or later (the "GPL"),
28 * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
29 * in which case the provisions of the GPL or the LGPL are applicable instead
30 * of those above. If you wish to allow use of your version of this file only
31 * under the terms of either the GPL or the LGPL, and not to allow others to
32 * use your version of this file under the terms of the MPL, indicate your
33 * decision by deleting the provisions above and replace them with the notice
34 * and other provisions required by the GPL or the LGPL. If you do not delete
35 * the provisions above, a recipient may use your version of this file under
36 * the terms of any one of the MPL, the GPL or the LGPL.
37 *
38 * ***** END LICENSE BLOCK ***** */
40 /*
41 * JS execution context.
42 */
43 #include "jsstddef.h"
44 #include <stdarg.h>
45 #include <stdlib.h>
46 #include <string.h>
47 #include "jstypes.h"
48 #include "jsarena.h" /* Added by JSIFY */
49 #include "jsutil.h" /* Added by JSIFY */
50 #include "jsclist.h"
51 #include "jsprf.h"
52 #include "jsatom.h"
53 #include "jscntxt.h"
54 #include "jsconfig.h"
55 #include "jsdbgapi.h"
56 #include "jsexn.h"
57 #include "jsgc.h"
58 #include "jslock.h"
59 #include "jsnum.h"
60 #include "jsobj.h"
61 #include "jsopcode.h"
62 #include "jsscan.h"
63 #include "jsscript.h"
64 #include "jsstr.h"
66 JSContext *
67 js_NewContext(JSRuntime *rt, size_t stackChunkSize)
68 {
69 JSContext *cx;
70 JSBool ok, first;
72 cx = (JSContext *) malloc(sizeof *cx);
73 if (!cx)
74 return NULL;
75 memset(cx, 0, sizeof *cx);
77 cx->runtime = rt;
78 #if JS_STACK_GROWTH_DIRECTION > 0
79 cx->stackLimit = (jsuword)-1;
80 #endif
81 #ifdef JS_THREADSAFE
82 js_InitContextForLocking(cx);
83 #endif
85 JS_LOCK_GC(rt);
86 for (;;) {
87 first = (rt->contextList.next == &rt->contextList);
88 if (rt->state == JSRTS_UP) {
89 JS_ASSERT(!first);
90 break;
91 }
92 if (rt->state == JSRTS_DOWN) {
93 JS_ASSERT(first);
94 rt->state = JSRTS_LAUNCHING;
95 break;
96 }
97 JS_WAIT_CONDVAR(rt->stateChange, JS_NO_TIMEOUT);
98 }
99 JS_APPEND_LINK(&cx->links, &rt->contextList);
100 JS_UNLOCK_GC(rt);
102 /*
103 * First we do the infallible, every-time per-context initializations.
104 * Should a later, fallible initialization (js_InitRegExpStatics, e.g.,
105 * or the stuff under 'if (first)' below) fail, at least the version
106 * and arena-pools will be valid and safe to use (say, from the last GC
107 * done by js_DestroyContext).
108 */
109 cx->version = JSVERSION_DEFAULT;
110 cx->jsop_eq = JSOP_EQ;
111 cx->jsop_ne = JSOP_NE;
112 JS_InitArenaPool(&cx->stackPool, "stack", stackChunkSize, sizeof(jsval));
113 JS_InitArenaPool(&cx->tempPool, "temp", 1024, sizeof(jsdouble));
115 #if JS_HAS_REGEXPS
116 if (!js_InitRegExpStatics(cx, &cx->regExpStatics)) {
117 js_DestroyContext(cx, JS_NO_GC);
118 return NULL;
119 }
120 #endif
121 #if JS_HAS_EXCEPTIONS
122 cx->throwing = JS_FALSE;
123 #endif
125 /*
126 * If cx is the first context on this runtime, initialize well-known atoms,
127 * keywords, numbers, and strings. If one of these steps should fail, the
128 * runtime will be left in a partially initialized state, with zeroes and
129 * nulls stored in the default-initialized remainder of the struct. We'll
130 * clean the runtime up under js_DestroyContext, because cx will be "last"
131 * as well as "first".
132 */
133 if (first) {
134 ok = (rt->atomState.liveAtoms == 0)
135 ? js_InitAtomState(cx, &rt->atomState)
136 : js_InitPinnedAtoms(cx, &rt->atomState);
137 if (ok)
138 ok = js_InitScanner(cx);
139 if (ok)
140 ok = js_InitRuntimeNumberState(cx);
141 if (ok)
142 ok = js_InitRuntimeScriptState(cx);
143 if (ok)
144 ok = js_InitRuntimeStringState(cx);
145 if (!ok) {
146 js_DestroyContext(cx, JS_NO_GC);
147 return NULL;
148 }
150 JS_LOCK_GC(rt);
151 rt->state = JSRTS_UP;
152 JS_NOTIFY_ALL_CONDVAR(rt->stateChange);
153 JS_UNLOCK_GC(rt);
154 }
156 return cx;
157 }
159 void
160 js_DestroyContext(JSContext *cx, JSGCMode gcmode)
161 {
162 JSRuntime *rt;
163 JSBool last;
164 JSArgumentFormatMap *map;
165 JSLocalRootStack *lrs;
166 JSLocalRootChunk *lrc;
168 rt = cx->runtime;
170 /* Remove cx from context list first. */
171 JS_LOCK_GC(rt);
172 JS_ASSERT(rt->state == JSRTS_UP || rt->state == JSRTS_LAUNCHING);
173 JS_REMOVE_LINK(&cx->links);
174 last = (rt->contextList.next == &rt->contextList);
175 if (last)
176 rt->state = JSRTS_LANDING;
177 JS_UNLOCK_GC(rt);
179 if (last) {
180 #ifdef JS_THREADSAFE
181 /*
182 * If cx is not in a request already, begin one now so that we wait
183 * for any racing GC started on a not-last context to finish, before
184 * we plow ahead and unpin atoms. Note that even though we begin a
185 * request here if necessary, we end all requests on cx below before
186 * forcing a final GC. This lets any not-last context destruction
187 * racing in another thread try to force or maybe run the GC, but by
188 * that point, rt->state will not be JSRTS_UP, and that GC attempt
189 * will return early.
190 */
191 if (cx->requestDepth == 0)
192 JS_BeginRequest(cx);
193 #endif
195 /* Unpin all pinned atoms before final GC. */
196 js_UnpinPinnedAtoms(&rt->atomState);
198 /* Unlock and clear GC things held by runtime pointers. */
199 js_FinishRuntimeNumberState(cx);
200 js_FinishRuntimeStringState(cx);
202 /* Clear debugging state to remove GC roots. */
203 JS_ClearAllTraps(cx);
204 JS_ClearAllWatchPoints(cx);
205 }
207 #if JS_HAS_REGEXPS
208 /*
209 * Remove more GC roots in regExpStatics, then collect garbage.
210 * XXX anti-modularity alert: we rely on the call to js_RemoveRoot within
211 * XXX this function call to wait for any racing GC to complete, in the
212 * XXX case where JS_DestroyContext is called outside of a request on cx
213 */
214 js_FreeRegExpStatics(cx, &cx->regExpStatics);
215 #endif
217 #ifdef JS_THREADSAFE
218 /*
219 * Destroying a context implicitly calls JS_EndRequest(). Also, we must
220 * end our request here in case we are "last" -- in that event, another
221 * js_DestroyContext that was not last might be waiting in the GC for our
222 * request to end. We'll let it run below, just before we do the truly
223 * final GC and then free atom state.
224 *
225 * At this point, cx must be inaccessible to other threads. It's off the
226 * rt->contextList, and it should not be reachable via any object private
227 * data structure.
228 */
229 while (cx->requestDepth != 0)
230 JS_EndRequest(cx);
231 #endif
233 if (last) {
234 /* Always force, so we wait for any racing GC to finish. */
235 js_ForceGC(cx, GC_LAST_CONTEXT);
237 /* Iterate until no finalizer removes a GC root or lock. */
238 while (rt->gcPoke)
239 js_GC(cx, GC_LAST_CONTEXT);
241 /* Try to free atom state, now that no unrooted scripts survive. */
242 if (rt->atomState.liveAtoms == 0)
243 js_FreeAtomState(cx, &rt->atomState);
245 /* Now after the last GC can we free the script filename table. */
246 js_FinishRuntimeScriptState(cx);
248 /* Take the runtime down, now that it has no contexts or atoms. */
249 JS_LOCK_GC(rt);
250 rt->state = JSRTS_DOWN;
251 JS_NOTIFY_ALL_CONDVAR(rt->stateChange);
252 JS_UNLOCK_GC(rt);
253 } else {
254 if (gcmode == JS_FORCE_GC)
255 js_ForceGC(cx, 0);
256 else if (gcmode == JS_MAYBE_GC)
257 JS_MaybeGC(cx);
258 }
260 /* Free the stuff hanging off of cx. */
261 JS_FinishArenaPool(&cx->stackPool);
262 JS_FinishArenaPool(&cx->tempPool);
263 if (cx->lastMessage)
264 free(cx->lastMessage);
266 /* Remove any argument formatters. */
267 map = cx->argumentFormatMap;
268 while (map) {
269 JSArgumentFormatMap *temp = map;
270 map = map->next;
271 JS_free(cx, temp);
272 }
274 /* Destroy the resolve recursion damper. */
275 if (cx->resolvingTable) {
276 JS_DHashTableDestroy(cx->resolvingTable);
277 cx->resolvingTable = NULL;
278 }
280 lrs = cx->localRootStack;
281 if (lrs) {
282 while ((lrc = lrs->topChunk) != &lrs->firstChunk) {
283 lrs->topChunk = lrc->down;
284 JS_free(cx, lrc);
285 }
286 JS_free(cx, lrs);
287 }
289 /* Finally, free cx itself. */
290 free(cx);
291 }
293 JSBool
294 js_ValidContextPointer(JSRuntime *rt, JSContext *cx)
295 {
296 JSCList *cl;
298 for (cl = rt->contextList.next; cl != &rt->contextList; cl = cl->next) {
299 if (cl == &cx->links)
300 return JS_TRUE;
301 }
302 JS_RUNTIME_METER(rt, deadContexts);
303 return JS_FALSE;
304 }
306 JSContext *
307 js_ContextIterator(JSRuntime *rt, JSBool unlocked, JSContext **iterp)
308 {
309 JSContext *cx = *iterp;
311 if (unlocked)
312 JS_LOCK_GC(rt);
313 if (!cx)
314 cx = (JSContext *)&rt->contextList;
315 cx = (JSContext *)cx->links.next;
316 if (&cx->links == &rt->contextList)
317 cx = NULL;
318 *iterp = cx;
319 if (unlocked)
320 JS_UNLOCK_GC(rt);
321 return cx;
322 }
324 JS_STATIC_DLL_CALLBACK(const void *)
325 resolving_GetKey(JSDHashTable *table, JSDHashEntryHdr *hdr)
326 {
327 JSResolvingEntry *entry = (JSResolvingEntry *)hdr;
329 return &entry->key;
330 }
332 JS_STATIC_DLL_CALLBACK(JSDHashNumber)
333 resolving_HashKey(JSDHashTable *table, const void *ptr)
334 {
335 const JSResolvingKey *key = (const JSResolvingKey *)ptr;
337 return ((JSDHashNumber)key->obj >> JSVAL_TAGBITS) ^ key->id;
338 }
340 JS_PUBLIC_API(JSBool)
341 resolving_MatchEntry(JSDHashTable *table,
342 const JSDHashEntryHdr *hdr,
343 const void *ptr)
344 {
345 const JSResolvingEntry *entry = (const JSResolvingEntry *)hdr;
346 const JSResolvingKey *key = (const JSResolvingKey *)ptr;
348 return entry->key.obj == key->obj && entry->key.id == key->id;
349 }
351 static const JSDHashTableOps resolving_dhash_ops = {
352 JS_DHashAllocTable,
353 JS_DHashFreeTable,
354 resolving_GetKey,
355 resolving_HashKey,
356 resolving_MatchEntry,
357 JS_DHashMoveEntryStub,
358 JS_DHashClearEntryStub,
359 JS_DHashFinalizeStub,
360 NULL
361 };
363 JSBool
364 js_StartResolving(JSContext *cx, JSResolvingKey *key, uint32 flag,
365 JSResolvingEntry **entryp)
366 {
367 JSDHashTable *table;
368 JSResolvingEntry *entry;
370 table = cx->resolvingTable;
371 if (!table) {
372 table = JS_NewDHashTable(&resolving_dhash_ops, NULL,
373 sizeof(JSResolvingEntry),
374 JS_DHASH_MIN_SIZE);
375 if (!table)
376 goto outofmem;
377 cx->resolvingTable = table;
378 }
380 entry = (JSResolvingEntry *)
381 JS_DHashTableOperate(table, key, JS_DHASH_ADD);
382 if (!entry)
383 goto outofmem;
385 if (entry->flags & flag) {
386 /* An entry for (key, flag) exists already -- dampen recursion. */
387 entry = NULL;
388 } else {
389 /* Fill in key if we were the first to add entry, then set flag. */
390 if (!entry->key.obj)
391 entry->key = *key;
392 entry->flags |= flag;
393 }
394 *entryp = entry;
395 return JS_TRUE;
397 outofmem:
398 JS_ReportOutOfMemory(cx);
399 return JS_FALSE;
400 }
402 void
403 js_StopResolving(JSContext *cx, JSResolvingKey *key, uint32 flag,
404 JSResolvingEntry *entry, uint32 generation)
405 {
406 JSDHashTable *table;
408 /*
409 * Clear flag from entry->flags and return early if other flags remain.
410 * We must take care to re-lookup entry if the table has changed since
411 * it was found by js_StartResolving.
412 */
413 table = cx->resolvingTable;
414 if (!entry || table->generation != generation) {
415 entry = (JSResolvingEntry *)
416 JS_DHashTableOperate(table, key, JS_DHASH_LOOKUP);
417 }
418 JS_ASSERT(JS_DHASH_ENTRY_IS_BUSY(&entry->hdr));
419 entry->flags &= ~flag;
420 if (entry->flags)
421 return;
423 /*
424 * Do a raw remove only if fewer entries were removed than would cause
425 * alpha to be less than .5 (alpha is at most .75). Otherwise, we just
426 * call JS_DHashTableOperate to re-lookup the key and remove its entry,
427 * compressing or shrinking the table as needed.
428 */
429 if (table->removedCount < JS_DHASH_TABLE_SIZE(table) >> 2)
430 JS_DHashTableRawRemove(table, &entry->hdr);
431 else
432 JS_DHashTableOperate(table, key, JS_DHASH_REMOVE);
433 }
435 JSBool
436 js_EnterLocalRootScope(JSContext *cx)
437 {
438 JSLocalRootStack *lrs;
439 int mark;
441 lrs = cx->localRootStack;
442 if (!lrs) {
443 lrs = (JSLocalRootStack *) JS_malloc(cx, sizeof *lrs);
444 if (!lrs)
445 return JS_FALSE;
446 lrs->scopeMark = JSLRS_NULL_MARK;
447 lrs->rootCount = 0;
448 lrs->topChunk = &lrs->firstChunk;
449 lrs->firstChunk.down = NULL;
450 cx->localRootStack = lrs;
451 }
453 /* Push lrs->scopeMark to save it for restore when leaving. */
454 mark = js_PushLocalRoot(cx, lrs, INT_TO_JSVAL(lrs->scopeMark));
455 if (mark < 0)
456 return JS_FALSE;
457 lrs->scopeMark = (uint16) mark;
458 return JS_TRUE;
459 }
461 void
462 js_LeaveLocalRootScope(JSContext *cx)
463 {
464 JSLocalRootStack *lrs;
465 unsigned mark, m, n;
466 JSLocalRootChunk *lrc;
468 /* Defend against buggy native callers. */
469 lrs = cx->localRootStack;
470 JS_ASSERT(lrs && lrs->rootCount != 0);
471 if (!lrs || lrs->rootCount == 0)
472 return;
474 mark = lrs->scopeMark;
475 JS_ASSERT(mark != JSLRS_NULL_MARK);
476 if (mark == JSLRS_NULL_MARK)
477 return;
479 /* Free any chunks being popped by this leave operation. */
480 m = mark >> JSLRS_CHUNK_SHIFT;
481 n = (lrs->rootCount - 1) >> JSLRS_CHUNK_SHIFT;
482 while (n > m) {
483 lrc = lrs->topChunk;
484 JS_ASSERT(lrc != &lrs->firstChunk);
485 lrs->topChunk = lrc->down;
486 JS_free(cx, lrc);
487 --n;
488 }
490 /* Pop the scope, restoring lrs->scopeMark. */
491 lrc = lrs->topChunk;
492 m = mark & JSLRS_CHUNK_MASK;
493 lrs->scopeMark = JSVAL_TO_INT(lrc->roots[m]);
494 lrc->roots[m] = JSVAL_NULL;
495 lrs->rootCount = (uint16) mark;
497 /*
498 * Free the stack eagerly, risking malloc churn. The alternative would
499 * require an lrs->entryCount member, maintained by Enter and Leave, and
500 * tested by the GC in addition to the cx->localRootStack non-null test.
501 *
502 * That approach would risk hoarding 264 bytes (net) per context. Right
503 * now it seems better to give fresh (dirty in CPU write-back cache, and
504 * the data is no longer needed) memory back to the malloc heap.
505 */
506 if (mark == 0) {
507 cx->localRootStack = NULL;
508 JS_free(cx, lrs);
509 } else if (m == 0) {
510 lrs->topChunk = lrc->down;
511 JS_free(cx, lrc);
512 }
513 }
515 void
516 js_ForgetLocalRoot(JSContext *cx, jsval v)
517 {
518 JSLocalRootStack *lrs;
519 unsigned i, j, m, n, mark;
520 JSLocalRootChunk *lrc, *lrc2;
521 jsval top;
523 lrs = cx->localRootStack;
524 JS_ASSERT(lrs && lrs->rootCount);
525 if (!lrs || lrs->rootCount == 0)
526 return;
528 /* Prepare to pop the top-most value from the stack. */
529 n = lrs->rootCount - 1;
530 m = n & JSLRS_CHUNK_MASK;
531 lrc = lrs->topChunk;
532 top = lrc->roots[m];
534 /* Be paranoid about calls on an empty scope. */
535 mark = lrs->scopeMark;
536 JS_ASSERT(mark < n);
537 if (mark >= n)
538 return;
540 /* If v was not the last root pushed in the top scope, find it. */
541 if (top != v) {
542 /* Search downward in case v was recently pushed. */
543 i = n;
544 j = m;
545 lrc2 = lrc;
546 while (--i > mark) {
547 if (j == 0)
548 lrc2 = lrc2->down;
549 j = i & JSLRS_CHUNK_MASK;
550 if (lrc2->roots[j] == v)
551 break;
552 }
554 /* If we didn't find v in this scope, assert and bail out. */
555 JS_ASSERT(i != mark);
556 if (i == mark)
557 return;
559 /* Swap top and v so common tail code can pop v. */
560 lrc2->roots[j] = top;
561 }
563 /* Pop the last value from the stack. */
564 lrc->roots[m] = JSVAL_NULL;
565 lrs->rootCount = n;
566 if (m == 0) {
567 JS_ASSERT(n != 0);
568 JS_ASSERT(lrc != &lrs->firstChunk);
569 lrs->topChunk = lrc->down;
570 JS_free(cx, lrc);
571 }
572 }
574 int
575 js_PushLocalRoot(JSContext *cx, JSLocalRootStack *lrs, jsval v)
576 {
577 unsigned n, m;
578 JSLocalRootChunk *lrc;
580 n = lrs->rootCount;
581 m = n & JSLRS_CHUNK_MASK;
582 if (n == 0 || m != 0) {
583 /*
584 * At start of first chunk, or not at start of a non-first top chunk.
585 * Check for lrs->rootCount overflow.
586 */
587 if ((uint16)(n + 1) == 0) {
588 JS_ReportErrorNumber(cx, js_GetErrorMessage, NULL,
589 JSMSG_TOO_MANY_LOCAL_ROOTS);
590 return -1;
591 }
592 lrc = lrs->topChunk;
593 JS_ASSERT(n != 0 || lrc == &lrs->firstChunk);
594 } else {
595 /*
596 * After lrs->firstChunk, trying to index at a power-of-two chunk
597 * boundary: need a new chunk.
598 */
599 lrc = (JSLocalRootChunk *) JS_malloc(cx, sizeof *lrc);
600 if (!lrc)
601 return -1;
602 lrc->down = lrs->topChunk;
603 lrs->topChunk = lrc;
604 }
605 lrs->rootCount = n + 1;
606 lrc->roots[m] = v;
607 return (int) m;
608 }
610 void
611 js_MarkLocalRoots(JSContext *cx, JSLocalRootStack *lrs)
612 {
613 unsigned n, m, mark;
614 JSLocalRootChunk *lrc;
616 n = lrs->rootCount;
617 if (n == 0)
618 return;
620 mark = lrs->scopeMark;
621 lrc = lrs->topChunk;
622 while (--n > mark) {
623 #ifdef GC_MARK_DEBUG
624 char name[22];
625 JS_snprintf(name, sizeof name, "<local root %u>", n);
626 #else
627 const char *name = NULL;
628 #endif
629 m = n & JSLRS_CHUNK_MASK;
630 JS_ASSERT(JSVAL_IS_GCTHING(lrc->roots[m]));
631 JS_MarkGCThing(cx, JSVAL_TO_GCTHING(lrc->roots[m]), name, NULL);
632 if (m == 0)
633 lrc = lrc->down;
634 }
635 }
637 static void
638 ReportError(JSContext *cx, const char *message, JSErrorReport *reportp)
639 {
640 /*
641 * Check the error report, and set a JavaScript-catchable exception
642 * if the error is defined to have an associated exception. If an
643 * exception is thrown, then the JSREPORT_EXCEPTION flag will be set
644 * on the error report, and exception-aware hosts should ignore it.
645 */
646 if (reportp && reportp->errorNumber == JSMSG_UNCAUGHT_EXCEPTION)
647 reportp->flags |= JSREPORT_EXCEPTION;
649 #if JS_HAS_ERROR_EXCEPTIONS
650 /*
651 * Call the error reporter only if an exception wasn't raised.
652 *
653 * If an exception was raised, then we call the debugErrorHook
654 * (if present) to give it a chance to see the error before it
655 * propagates out of scope. This is needed for compatability
656 * with the old scheme.
657 */
658 if (!js_ErrorToException(cx, message, reportp)) {
659 js_ReportErrorAgain(cx, message, reportp);
660 } else if (cx->runtime->debugErrorHook && cx->errorReporter) {
661 JSDebugErrorHook hook = cx->runtime->debugErrorHook;
662 /* test local in case debugErrorHook changed on another thread */
663 if (hook)
664 hook(cx, message, reportp, cx->runtime->debugErrorHookData);
665 }
666 #else
667 js_ReportErrorAgain(cx, message, reportp);
668 #endif
669 }
671 /*
672 * We don't post an exception in this case, since doing so runs into
673 * complications of pre-allocating an exception object which required
674 * running the Exception class initializer early etc.
675 * Instead we just invoke the errorReporter with an "Out Of Memory"
676 * type message, and then hope the process ends swiftly.
677 */
678 void
679 js_ReportOutOfMemory(JSContext *cx, JSErrorCallback callback)
680 {
681 JSStackFrame *fp;
682 JSErrorReport report;
683 JSErrorReporter onError = cx->errorReporter;
685 /* Get the message for this error, but we won't expand any arguments. */
686 const JSErrorFormatString *efs = callback(NULL, NULL, JSMSG_OUT_OF_MEMORY);
687 const char *msg = efs ? efs->format : "Out of memory";
689 /* Fill out the report, but don't do anything that requires allocation. */
690 memset(&report, 0, sizeof (struct JSErrorReport));
691 report.flags = JSREPORT_ERROR;
692 report.errorNumber = JSMSG_OUT_OF_MEMORY;
694 /*
695 * Walk stack until we find a frame that is associated with some script
696 * rather than a native frame.
697 */
698 for (fp = cx->fp; fp; fp = fp->down) {
699 if (fp->script && fp->pc) {
700 report.filename = fp->script->filename;
701 report.lineno = js_PCToLineNumber(cx, fp->script, fp->pc);
702 break;
703 }
704 }
706 /*
707 * If debugErrorHook is present then we give it a chance to veto
708 * sending the error on to the regular ErrorReporter.
709 */
710 if (onError) {
711 JSDebugErrorHook hook = cx->runtime->debugErrorHook;
712 if (hook &&
713 !hook(cx, msg, &report, cx->runtime->debugErrorHookData)) {
714 onError = NULL;
715 }
716 }
718 if (onError)
719 onError(cx, msg, &report);
720 }
722 JSBool
723 js_ReportErrorVA(JSContext *cx, uintN flags, const char *format, va_list ap)
724 {
725 char *last;
726 JSStackFrame *fp;
727 JSErrorReport report;
728 JSBool warning;
730 if ((flags & JSREPORT_STRICT) && !JS_HAS_STRICT_OPTION(cx))
731 return JS_TRUE;
733 last = JS_vsmprintf(format, ap);
734 if (!last)
735 return JS_FALSE;
737 memset(&report, 0, sizeof (struct JSErrorReport));
738 report.flags = flags;
740 /* Find the top-most active script frame, for best line number blame. */
741 for (fp = cx->fp; fp; fp = fp->down) {
742 if (fp->script && fp->pc) {
743 report.filename = fp->script->filename;
744 report.lineno = js_PCToLineNumber(cx, fp->script, fp->pc);
745 break;
746 }
747 }
749 warning = JSREPORT_IS_WARNING(report.flags);
750 if (warning && JS_HAS_WERROR_OPTION(cx)) {
751 report.flags &= ~JSREPORT_WARNING;
752 warning = JS_FALSE;
753 }
755 ReportError(cx, last, &report);
756 free(last);
757 return warning;
758 }
760 /*
761 * The arguments from ap need to be packaged up into an array and stored
762 * into the report struct.
763 *
764 * The format string addressed by the error number may contain operands
765 * identified by the format {N}, where N is a decimal digit. Each of these
766 * is to be replaced by the Nth argument from the va_list. The complete
767 * message is placed into reportp->ucmessage converted to a JSString.
768 *
769 * Returns true if the expansion succeeds (can fail if out of memory).
770 */
771 JSBool
772 js_ExpandErrorArguments(JSContext *cx, JSErrorCallback callback,
773 void *userRef, const uintN errorNumber,
774 char **messagep, JSErrorReport *reportp,
775 JSBool *warningp, JSBool charArgs, va_list ap)
776 {
777 const JSErrorFormatString *efs;
778 int i;
779 int argCount;
781 *warningp = JSREPORT_IS_WARNING(reportp->flags);
782 if (*warningp && JS_HAS_WERROR_OPTION(cx)) {
783 reportp->flags &= ~JSREPORT_WARNING;
784 *warningp = JS_FALSE;
785 }
787 *messagep = NULL;
788 if (callback) {
789 efs = callback(userRef, NULL, errorNumber);
790 if (efs) {
791 size_t totalArgsLength = 0;
792 size_t argLengths[10]; /* only {0} thru {9} supported */
793 argCount = efs->argCount;
794 JS_ASSERT(argCount <= 10);
795 if (argCount > 0) {
796 /*
797 * Gather the arguments into an array, and accumulate
798 * their sizes. We allocate 1 more than necessary and
799 * null it out to act as the caboose when we free the
800 * pointers later.
801 */
802 reportp->messageArgs = (const jschar **)
803 JS_malloc(cx, sizeof(jschar *) * (argCount + 1));
804 if (!reportp->messageArgs)
805 return JS_FALSE;
806 reportp->messageArgs[argCount] = NULL;
807 for (i = 0; i < argCount; i++) {
808 if (charArgs) {
809 char *charArg = va_arg(ap, char *);
810 reportp->messageArgs[i]
811 = js_InflateString(cx, charArg, strlen(charArg));
812 if (!reportp->messageArgs[i])
813 goto error;
814 }
815 else
816 reportp->messageArgs[i] = va_arg(ap, jschar *);
817 argLengths[i] = js_strlen(reportp->messageArgs[i]);
818 totalArgsLength += argLengths[i];
819 }
820 /* NULL-terminate for easy copying. */
821 reportp->messageArgs[i] = NULL;
822 }
823 /*
824 * Parse the error format, substituting the argument X
825 * for {X} in the format.
826 */
827 if (argCount > 0) {
828 if (efs->format) {
829 const char *fmt;
830 const jschar *arg;
831 jschar *out;
832 int expandedArgs = 0;
833 size_t expandedLength
834 = strlen(efs->format)
835 - (3 * argCount) /* exclude the {n} */
836 + totalArgsLength;
837 /*
838 * Note - the above calculation assumes that each argument
839 * is used once and only once in the expansion !!!
840 */
841 reportp->ucmessage = out = (jschar *)
842 JS_malloc(cx, (expandedLength + 1) * sizeof(jschar));
843 if (!out)
844 goto error;
845 fmt = efs->format;
846 while (*fmt) {
847 if (*fmt == '{') {
848 if (isdigit(fmt[1])) {
849 int d = JS7_UNDEC(fmt[1]);
850 JS_ASSERT(expandedArgs < argCount);
851 arg = reportp->messageArgs[d];
852 js_strncpy(out, arg, argLengths[d]);
853 out += argLengths[d];
854 fmt += 3;
855 expandedArgs++;
856 continue;
857 }
858 }
859 /*
860 * is this kosher?
861 */
862 *out++ = (unsigned char)(*fmt++);
863 }
864 JS_ASSERT(expandedArgs == argCount);
865 *out = 0;
866 *messagep =
867 js_DeflateString(cx, reportp->ucmessage,
868 (size_t)(out - reportp->ucmessage));
869 if (!*messagep)
870 goto error;
871 }
872 } else {
873 /*
874 * Zero arguments: the format string (if it exists) is the
875 * entire message.
876 */
877 if (efs->format) {
878 *messagep = JS_strdup(cx, efs->format);
879 if (!*messagep)
880 goto error;
881 reportp->ucmessage
882 = js_InflateString(cx, *messagep, strlen(*messagep));
883 if (!reportp->ucmessage)
884 goto error;
885 }
886 }
887 }
888 }
889 if (*messagep == NULL) {
890 /* where's the right place for this ??? */
891 const char *defaultErrorMessage
892 = "No error message available for error number %d";
893 size_t nbytes = strlen(defaultErrorMessage) + 16;
894 *messagep = (char *)JS_malloc(cx, nbytes);
895 if (!*messagep)
896 goto error;
897 JS_snprintf(*messagep, nbytes, defaultErrorMessage, errorNumber);
898 }
899 return JS_TRUE;
901 error:
902 if (reportp->messageArgs) {
903 i = 0;
904 while (reportp->messageArgs[i])
905 JS_free(cx, (void *)reportp->messageArgs[i++]);
906 JS_free(cx, (void *)reportp->messageArgs);
907 reportp->messageArgs = NULL;
908 }
909 if (reportp->ucmessage) {
910 JS_free(cx, (void *)reportp->ucmessage);
911 reportp->ucmessage = NULL;
912 }
913 if (*messagep) {
914 JS_free(cx, (void *)*messagep);
915 *messagep = NULL;
916 }
917 return JS_FALSE;
918 }
920 JSBool
921 js_ReportErrorNumberVA(JSContext *cx, uintN flags, JSErrorCallback callback,
922 void *userRef, const uintN errorNumber,
923 JSBool charArgs, va_list ap)
924 {
925 JSStackFrame *fp;
926 JSErrorReport report;
927 char *message;
928 JSBool warning;
930 if ((flags & JSREPORT_STRICT) && !JS_HAS_STRICT_OPTION(cx))
931 return JS_TRUE;
933 memset(&report, 0, sizeof (struct JSErrorReport));
934 report.flags = flags;
935 report.errorNumber = errorNumber;
937 /*
938 * If we can't find out where the error was based on the current frame,
939 * see if the next frame has a script/pc combo we can use.
940 */
941 for (fp = cx->fp; fp; fp = fp->down) {
942 if (fp->script && fp->pc) {
943 report.filename = fp->script->filename;
944 report.lineno = js_PCToLineNumber(cx, fp->script, fp->pc);
945 break;
946 }
947 }
949 if (!js_ExpandErrorArguments(cx, callback, userRef, errorNumber,
950 &message, &report, &warning, charArgs, ap)) {
951 return JS_FALSE;
952 }
954 ReportError(cx, message, &report);
956 if (message)
957 JS_free(cx, message);
958 if (report.messageArgs) {
959 int i = 0;
960 while (report.messageArgs[i])
961 JS_free(cx, (void *)report.messageArgs[i++]);
962 JS_free(cx, (void *)report.messageArgs);
963 }
964 if (report.ucmessage)
965 JS_free(cx, (void *)report.ucmessage);
967 return warning;
968 }
970 JS_FRIEND_API(void)
971 js_ReportErrorAgain(JSContext *cx, const char *message, JSErrorReport *reportp)
972 {
973 JSErrorReporter onError;
975 if (!message)
976 return;
978 if (cx->lastMessage)
979 free(cx->lastMessage);
980 cx->lastMessage = JS_strdup(cx, message);
981 if (!cx->lastMessage)
982 return;
983 onError = cx->errorReporter;
985 /*
986 * If debugErrorHook is present then we give it a chance to veto
987 * sending the error on to the regular ErrorReporter.
988 */
989 if (onError) {
990 JSDebugErrorHook hook = cx->runtime->debugErrorHook;
991 if (hook &&
992 !hook(cx, cx->lastMessage, reportp,
993 cx->runtime->debugErrorHookData)) {
994 onError = NULL;
995 }
996 }
997 if (onError)
998 onError(cx, cx->lastMessage, reportp);
999 }
1001 void
1002 js_ReportIsNotDefined(JSContext *cx, const char *name)
1003 {
1004 JS_ReportErrorNumber(cx, js_GetErrorMessage, NULL, JSMSG_NOT_DEFINED, name);
1005 }
1007 #if defined DEBUG && defined XP_UNIX
1008 /* For gdb usage. */
1009 void js_traceon(JSContext *cx) { cx->tracefp = stderr; }
1010 void js_traceoff(JSContext *cx) { cx->tracefp = NULL; }
1011 #endif
1013 JSErrorFormatString js_ErrorFormatString[JSErr_Limit] = {
1014 #if JS_HAS_DFLT_MSG_STRINGS
1015 #define MSG_DEF(name, number, count, exception, format) \
1016 { format, count } ,
1017 #else
1018 #define MSG_DEF(name, number, count, exception, format) \
1019 { NULL, count } ,
1020 #endif
1021 #include "js.msg"
1022 #undef MSG_DEF
1023 };
1025 const JSErrorFormatString *
1026 js_GetErrorMessage(void *userRef, const char *locale, const uintN errorNumber)
1027 {
1028 if ((errorNumber > 0) && (errorNumber < JSErr_Limit))
1029 return &js_ErrorFormatString[errorNumber];
1030 return NULL;
1031 }