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jscntxt.c
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jscntxt.c
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/* -*- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
* vim: set ts=8 sw=4 et tw=80:
*
* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is Mozilla Communicator client code, released
* March 31, 1998.
*
* The Initial Developer of the Original Code is
* Netscape Communications Corporation.
* Portions created by the Initial Developer are Copyright (C) 1998
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
*
* Alternatively, the contents of this file may be used under the terms of
* either of the GNU General Public License Version 2 or later (the "GPL"),
* or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
/*
* JS execution context.
*/
#include "jsstddef.h"
#include <stdarg.h>
#include <stdlib.h>
#include <string.h>
#include "jstypes.h"
#include "jsarena.h" /* Added by JSIFY */
#include "jsutil.h" /* Added by JSIFY */
#include "jsclist.h"
#include "jsprf.h"
#include "jsatom.h"
#include "jscntxt.h"
#include "jsconfig.h"
#include "jsdbgapi.h"
#include "jsexn.h"
#include "jsgc.h"
#include "jslock.h"
#include "jsnum.h"
#include "jsobj.h"
#include "jsopcode.h"
#include "jsscan.h"
#include "jsscope.h"
#include "jsscript.h"
#include "jsstr.h"
#ifdef JS_THREADSAFE
/*
* Callback function to delete a JSThread info when the thread that owns it
* is destroyed.
*/
void JS_DLL_CALLBACK
js_ThreadDestructorCB(void *ptr)
{
JSThread *thread = (JSThread *)ptr;
if (!thread)
return;
while (!JS_CLIST_IS_EMPTY(&thread->contextList)) {
/* NB: use a temporary, as the macro evaluates its args many times. */
JSCList *link = thread->contextList.next;
JS_REMOVE_AND_INIT_LINK(link);
}
GSN_CACHE_CLEAR(&thread->gsnCache);
free(thread);
}
/*
* Get current thread-local JSThread info, creating one if it doesn't exist.
* Each thread has a unique JSThread pointer.
*
* Since we are dealing with thread-local data, no lock is needed.
*
* Return a pointer to the thread local info, NULL if the system runs out
* of memory, or it failed to set thread private data (neither case is very
* likely; both are probably due to out-of-memory). It is up to the caller
* to report an error, if possible.
*/
JSThread *
js_GetCurrentThread(JSRuntime *rt)
{
JSThread *thread;
thread = (JSThread *)PR_GetThreadPrivate(rt->threadTPIndex);
if (!thread) {
thread = (JSThread *) calloc(1, sizeof(JSThread));
if (!thread)
return NULL;
if (PR_FAILURE == PR_SetThreadPrivate(rt->threadTPIndex, thread)) {
free(thread);
return NULL;
}
JS_INIT_CLIST(&thread->contextList);
thread->id = js_CurrentThreadId();
/* js_SetContextThread initialize gcFreeLists as necessary. */
#ifdef DEBUG
memset(thread->gcFreeLists, JS_FREE_PATTERN,
sizeof(thread->gcFreeLists));
#endif
}
return thread;
}
/*
* Sets current thread as owning thread of a context by assigning the
* thread-private info to the context. If the current thread doesn't have
* private JSThread info, create one.
*/
JSBool
js_SetContextThread(JSContext *cx)
{
JSThread *thread = js_GetCurrentThread(cx->runtime);
if (!thread) {
JS_ReportOutOfMemory(cx);
return JS_FALSE;
}
/*
* Clear gcFreeLists on each transition from 0 to 1 context active on the
* current thread. See bug 351602.
*/
if (JS_CLIST_IS_EMPTY(&thread->contextList))
memset(thread->gcFreeLists, 0, sizeof(thread->gcFreeLists));
cx->thread = thread;
JS_REMOVE_LINK(&cx->threadLinks);
JS_APPEND_LINK(&cx->threadLinks, &thread->contextList);
return JS_TRUE;
}
/* Remove the owning thread info of a context. */
void
js_ClearContextThread(JSContext *cx)
{
JS_REMOVE_AND_INIT_LINK(&cx->threadLinks);
#ifdef DEBUG
if (JS_CLIST_IS_EMPTY(&cx->thread->contextList)) {
memset(cx->thread->gcFreeLists, JS_FREE_PATTERN,
sizeof(cx->thread->gcFreeLists));
}
#endif
cx->thread = NULL;
}
#endif /* JS_THREADSAFE */
void
js_OnVersionChange(JSContext *cx)
{
#ifdef DEBUG
JSVersion version = JSVERSION_NUMBER(cx);
JS_ASSERT(version == JSVERSION_DEFAULT || version >= JSVERSION_ECMA_3);
#endif
}
void
js_SetVersion(JSContext *cx, JSVersion version)
{
cx->version = version;
js_OnVersionChange(cx);
}
JSContext *
js_NewContext(JSRuntime *rt, size_t stackChunkSize)
{
JSContext *cx;
JSBool ok, first;
JSContextCallback cxCallback;
cx = (JSContext *) malloc(sizeof *cx);
if (!cx)
return NULL;
memset(cx, 0, sizeof *cx);
cx->runtime = rt;
#if JS_STACK_GROWTH_DIRECTION > 0
cx->stackLimit = (jsuword)-1;
#endif
#ifdef JS_THREADSAFE
JS_INIT_CLIST(&cx->threadLinks);
js_SetContextThread(cx);
#endif
JS_LOCK_GC(rt);
for (;;) {
first = (rt->contextList.next == &rt->contextList);
if (rt->state == JSRTS_UP) {
JS_ASSERT(!first);
break;
}
if (rt->state == JSRTS_DOWN) {
JS_ASSERT(first);
rt->state = JSRTS_LAUNCHING;
break;
}
JS_WAIT_CONDVAR(rt->stateChange, JS_NO_TIMEOUT);
}
JS_APPEND_LINK(&cx->links, &rt->contextList);
JS_UNLOCK_GC(rt);
/*
* First we do the infallible, every-time per-context initializations.
* Should a later, fallible initialization (js_InitRegExpStatics, e.g.,
* or the stuff under 'if (first)' below) fail, at least the version
* and arena-pools will be valid and safe to use (say, from the last GC
* done by js_DestroyContext).
*/
cx->version = JSVERSION_DEFAULT;
cx->jsop_eq = JSOP_EQ;
cx->jsop_ne = JSOP_NE;
JS_InitArenaPool(&cx->stackPool, "stack", stackChunkSize, sizeof(jsval));
JS_InitArenaPool(&cx->tempPool, "temp", 1024, sizeof(jsdouble));
if (!js_InitRegExpStatics(cx, &cx->regExpStatics)) {
js_DestroyContext(cx, JSDCM_NEW_FAILED);
return NULL;
}
/*
* If cx is the first context on this runtime, initialize well-known atoms,
* keywords, numbers, and strings. If one of these steps should fail, the
* runtime will be left in a partially initialized state, with zeroes and
* nulls stored in the default-initialized remainder of the struct. We'll
* clean the runtime up under js_DestroyContext, because cx will be "last"
* as well as "first".
*/
if (first) {
#ifdef JS_THREADSAFE
JS_BeginRequest(cx);
#endif
/*
* Both atomState and the scriptFilenameTable may be left over from a
* previous episode of non-zero contexts alive in rt, so don't re-init
* either table if it's not necessary. Just repopulate atomState with
* well-known internal atoms, and with the reserved identifiers added
* by the scanner.
*/
ok = (rt->atomState.liveAtoms == 0)
? js_InitAtomState(cx, &rt->atomState)
: js_InitPinnedAtoms(cx, &rt->atomState);
if (ok && !rt->scriptFilenameTable)
ok = js_InitRuntimeScriptState(rt);
if (ok)
ok = js_InitRuntimeNumberState(cx);
if (ok)
ok = js_InitRuntimeStringState(cx);
#ifdef JS_THREADSAFE
JS_EndRequest(cx);
#endif
if (!ok) {
js_DestroyContext(cx, JSDCM_NEW_FAILED);
return NULL;
}
JS_LOCK_GC(rt);
rt->state = JSRTS_UP;
JS_NOTIFY_ALL_CONDVAR(rt->stateChange);
JS_UNLOCK_GC(rt);
}
cxCallback = rt->cxCallback;
if (cxCallback && !cxCallback(cx, JSCONTEXT_NEW)) {
js_DestroyContext(cx, JSDCM_NEW_FAILED);
return NULL;
}
return cx;
}
void
js_DestroyContext(JSContext *cx, JSDestroyContextMode mode)
{
JSRuntime *rt;
JSContextCallback cxCallback;
JSBool last;
JSArgumentFormatMap *map;
JSLocalRootStack *lrs;
JSLocalRootChunk *lrc;
rt = cx->runtime;
if (mode != JSDCM_NEW_FAILED) {
cxCallback = rt->cxCallback;
if (cxCallback) {
/*
* JSCONTEXT_DESTROY callback is not allowed to fail and must
* return true.
*/
#ifdef DEBUG
JSBool callbackStatus =
#endif
cxCallback(cx, JSCONTEXT_DESTROY);
JS_ASSERT(callbackStatus);
}
}
/* Remove cx from context list first. */
JS_LOCK_GC(rt);
JS_ASSERT(rt->state == JSRTS_UP || rt->state == JSRTS_LAUNCHING);
JS_REMOVE_LINK(&cx->links);
last = (rt->contextList.next == &rt->contextList);
if (last)
rt->state = JSRTS_LANDING;
JS_UNLOCK_GC(rt);
if (last) {
#ifdef JS_THREADSAFE
/*
* If cx is not in a request already, begin one now so that we wait
* for any racing GC started on a not-last context to finish, before
* we plow ahead and unpin atoms. Note that even though we begin a
* request here if necessary, we end all requests on cx below before
* forcing a final GC. This lets any not-last context destruction
* racing in another thread try to force or maybe run the GC, but by
* that point, rt->state will not be JSRTS_UP, and that GC attempt
* will return early.
*/
if (cx->requestDepth == 0)
JS_BeginRequest(cx);
#endif
/* Unpin all pinned atoms before final GC. */
js_UnpinPinnedAtoms(&rt->atomState);
/* Unlock and clear GC things held by runtime pointers. */
js_FinishRuntimeNumberState(cx);
js_FinishRuntimeStringState(cx);
/* Clear debugging state to remove GC roots. */
JS_ClearAllTraps(cx);
JS_ClearAllWatchPoints(cx);
}
/*
* Remove more GC roots in regExpStatics, then collect garbage.
* XXX anti-modularity alert: we rely on the call to js_RemoveRoot within
* XXX this function call to wait for any racing GC to complete, in the
* XXX case where JS_DestroyContext is called outside of a request on cx
*/
js_FreeRegExpStatics(cx, &cx->regExpStatics);
#ifdef JS_THREADSAFE
/*
* Destroying a context implicitly calls JS_EndRequest(). Also, we must
* end our request here in case we are "last" -- in that event, another
* js_DestroyContext that was not last might be waiting in the GC for our
* request to end. We'll let it run below, just before we do the truly
* final GC and then free atom state.
*
* At this point, cx must be inaccessible to other threads. It's off the
* rt->contextList, and it should not be reachable via any object private
* data structure.
*/
while (cx->requestDepth != 0)
JS_EndRequest(cx);
#endif
if (last) {
js_GC(cx, GC_LAST_CONTEXT);
/* Try to free atom state, now that no unrooted scripts survive. */
if (rt->atomState.liveAtoms == 0)
js_FreeAtomState(cx, &rt->atomState);
/* Also free the script filename table if it exists and is empty. */
if (rt->scriptFilenameTable && rt->scriptFilenameTable->nentries == 0)
js_FinishRuntimeScriptState(rt);
/*
* Free the deflated string cache, but only after the last GC has
* collected all unleaked strings.
*/
js_FinishDeflatedStringCache(rt);
/* Take the runtime down, now that it has no contexts or atoms. */
JS_LOCK_GC(rt);
rt->state = JSRTS_DOWN;
JS_NOTIFY_ALL_CONDVAR(rt->stateChange);
JS_UNLOCK_GC(rt);
} else {
if (mode == JSDCM_FORCE_GC)
js_GC(cx, GC_NORMAL);
else if (mode == JSDCM_MAYBE_GC)
JS_MaybeGC(cx);
}
/* Free the stuff hanging off of cx. */
JS_FinishArenaPool(&cx->stackPool);
JS_FinishArenaPool(&cx->tempPool);
if (cx->lastMessage)
free(cx->lastMessage);
/* Remove any argument formatters. */
map = cx->argumentFormatMap;
while (map) {
JSArgumentFormatMap *temp = map;
map = map->next;
JS_free(cx, temp);
}
/* Destroy the resolve recursion damper. */
if (cx->resolvingTable) {
JS_DHashTableDestroy(cx->resolvingTable);
cx->resolvingTable = NULL;
}
lrs = cx->localRootStack;
if (lrs) {
while ((lrc = lrs->topChunk) != &lrs->firstChunk) {
lrs->topChunk = lrc->down;
JS_free(cx, lrc);
}
JS_free(cx, lrs);
}
#ifdef JS_THREADSAFE
js_ClearContextThread(cx);
#endif
/* Finally, free cx itself. */
free(cx);
}
JSBool
js_ValidContextPointer(JSRuntime *rt, JSContext *cx)
{
JSCList *cl;
for (cl = rt->contextList.next; cl != &rt->contextList; cl = cl->next) {
if (cl == &cx->links)
return JS_TRUE;
}
JS_RUNTIME_METER(rt, deadContexts);
return JS_FALSE;
}
JSContext *
js_ContextIterator(JSRuntime *rt, JSBool unlocked, JSContext **iterp)
{
JSContext *cx = *iterp;
if (unlocked)
JS_LOCK_GC(rt);
if (!cx)
cx = (JSContext *)&rt->contextList;
cx = (JSContext *)cx->links.next;
if (&cx->links == &rt->contextList)
cx = NULL;
*iterp = cx;
if (unlocked)
JS_UNLOCK_GC(rt);
return cx;
}
JS_STATIC_DLL_CALLBACK(const void *)
resolving_GetKey(JSDHashTable *table, JSDHashEntryHdr *hdr)
{
JSResolvingEntry *entry = (JSResolvingEntry *)hdr;
return &entry->key;
}
JS_STATIC_DLL_CALLBACK(JSDHashNumber)
resolving_HashKey(JSDHashTable *table, const void *ptr)
{
const JSResolvingKey *key = (const JSResolvingKey *)ptr;
return ((JSDHashNumber)JS_PTR_TO_UINT32(key->obj) >> JSVAL_TAGBITS) ^ key->id;
}
JS_PUBLIC_API(JSBool)
resolving_MatchEntry(JSDHashTable *table,
const JSDHashEntryHdr *hdr,
const void *ptr)
{
const JSResolvingEntry *entry = (const JSResolvingEntry *)hdr;
const JSResolvingKey *key = (const JSResolvingKey *)ptr;
return entry->key.obj == key->obj && entry->key.id == key->id;
}
static const JSDHashTableOps resolving_dhash_ops = {
JS_DHashAllocTable,
JS_DHashFreeTable,
resolving_GetKey,
resolving_HashKey,
resolving_MatchEntry,
JS_DHashMoveEntryStub,
JS_DHashClearEntryStub,
JS_DHashFinalizeStub,
NULL
};
JSBool
js_StartResolving(JSContext *cx, JSResolvingKey *key, uint32 flag,
JSResolvingEntry **entryp)
{
JSDHashTable *table;
JSResolvingEntry *entry;
table = cx->resolvingTable;
if (!table) {
table = JS_NewDHashTable(&resolving_dhash_ops, NULL,
sizeof(JSResolvingEntry),
JS_DHASH_MIN_SIZE);
if (!table)
goto outofmem;
cx->resolvingTable = table;
}
entry = (JSResolvingEntry *)
JS_DHashTableOperate(table, key, JS_DHASH_ADD);
if (!entry)
goto outofmem;
if (entry->flags & flag) {
/* An entry for (key, flag) exists already -- dampen recursion. */
entry = NULL;
} else {
/* Fill in key if we were the first to add entry, then set flag. */
if (!entry->key.obj)
entry->key = *key;
entry->flags |= flag;
}
*entryp = entry;
return JS_TRUE;
outofmem:
JS_ReportOutOfMemory(cx);
return JS_FALSE;
}
void
js_StopResolving(JSContext *cx, JSResolvingKey *key, uint32 flag,
JSResolvingEntry *entry, uint32 generation)
{
JSDHashTable *table;
/*
* Clear flag from entry->flags and return early if other flags remain.
* We must take care to re-lookup entry if the table has changed since
* it was found by js_StartResolving.
*/
table = cx->resolvingTable;
if (!entry || table->generation != generation) {
entry = (JSResolvingEntry *)
JS_DHashTableOperate(table, key, JS_DHASH_LOOKUP);
}
JS_ASSERT(JS_DHASH_ENTRY_IS_BUSY(&entry->hdr));
entry->flags &= ~flag;
if (entry->flags)
return;
/*
* Do a raw remove only if fewer entries were removed than would cause
* alpha to be less than .5 (alpha is at most .75). Otherwise, we just
* call JS_DHashTableOperate to re-lookup the key and remove its entry,
* compressing or shrinking the table as needed.
*/
if (table->removedCount < JS_DHASH_TABLE_SIZE(table) >> 2)
JS_DHashTableRawRemove(table, &entry->hdr);
else
JS_DHashTableOperate(table, key, JS_DHASH_REMOVE);
}
JSBool
js_EnterLocalRootScope(JSContext *cx)
{
JSLocalRootStack *lrs;
int mark;
lrs = cx->localRootStack;
if (!lrs) {
lrs = (JSLocalRootStack *) JS_malloc(cx, sizeof *lrs);
if (!lrs)
return JS_FALSE;
lrs->scopeMark = JSLRS_NULL_MARK;
lrs->rootCount = 0;
lrs->topChunk = &lrs->firstChunk;
lrs->firstChunk.down = NULL;
cx->localRootStack = lrs;
}
/* Push lrs->scopeMark to save it for restore when leaving. */
mark = js_PushLocalRoot(cx, lrs, INT_TO_JSVAL(lrs->scopeMark));
if (mark < 0)
return JS_FALSE;
lrs->scopeMark = (uint32) mark;
return JS_TRUE;
}
void
js_LeaveLocalRootScopeWithResult(JSContext *cx, jsval rval)
{
JSLocalRootStack *lrs;
uint32 mark, m, n;
JSLocalRootChunk *lrc;
/* Defend against buggy native callers. */
lrs = cx->localRootStack;
JS_ASSERT(lrs && lrs->rootCount != 0);
if (!lrs || lrs->rootCount == 0)
return;
mark = lrs->scopeMark;
JS_ASSERT(mark != JSLRS_NULL_MARK);
if (mark == JSLRS_NULL_MARK)
return;
/* Free any chunks being popped by this leave operation. */
m = mark >> JSLRS_CHUNK_SHIFT;
n = (lrs->rootCount - 1) >> JSLRS_CHUNK_SHIFT;
while (n > m) {
lrc = lrs->topChunk;
JS_ASSERT(lrc != &lrs->firstChunk);
lrs->topChunk = lrc->down;
JS_free(cx, lrc);
--n;
}
/*
* Pop the scope, restoring lrs->scopeMark. If rval is a GC-thing, push
* it on the caller's scope, or store it in lastInternalResult if we are
* leaving the outermost scope. We don't need to allocate a new lrc
* because we can overwrite the old mark's slot with rval.
*/
lrc = lrs->topChunk;
m = mark & JSLRS_CHUNK_MASK;
lrs->scopeMark = (uint32) JSVAL_TO_INT(lrc->roots[m]);
if (JSVAL_IS_GCTHING(rval) && !JSVAL_IS_NULL(rval)) {
if (mark == 0) {
cx->weakRoots.lastInternalResult = rval;
} else {
/*
* Increment m to avoid the "else if (m == 0)" case below. If
* rval is not a GC-thing, that case would take care of freeing
* any chunk that contained only the old mark. Since rval *is*
* a GC-thing here, we want to reuse that old mark's slot.
*/
lrc->roots[m++] = rval;
++mark;
}
}
lrs->rootCount = (uint32) mark;
/*
* Free the stack eagerly, risking malloc churn. The alternative would
* require an lrs->entryCount member, maintained by Enter and Leave, and
* tested by the GC in addition to the cx->localRootStack non-null test.
*
* That approach would risk hoarding 264 bytes (net) per context. Right
* now it seems better to give fresh (dirty in CPU write-back cache, and
* the data is no longer needed) memory back to the malloc heap.
*/
if (mark == 0) {
cx->localRootStack = NULL;
JS_free(cx, lrs);
} else if (m == 0) {
lrs->topChunk = lrc->down;
JS_free(cx, lrc);
}
}
void
js_ForgetLocalRoot(JSContext *cx, jsval v)
{
JSLocalRootStack *lrs;
uint32 i, j, m, n, mark;
JSLocalRootChunk *lrc, *lrc2;
jsval top;
lrs = cx->localRootStack;
JS_ASSERT(lrs && lrs->rootCount);
if (!lrs || lrs->rootCount == 0)
return;
/* Prepare to pop the top-most value from the stack. */
n = lrs->rootCount - 1;
m = n & JSLRS_CHUNK_MASK;
lrc = lrs->topChunk;
top = lrc->roots[m];
/* Be paranoid about calls on an empty scope. */
mark = lrs->scopeMark;
JS_ASSERT(mark < n);
if (mark >= n)
return;
/* If v was not the last root pushed in the top scope, find it. */
if (top != v) {
/* Search downward in case v was recently pushed. */
i = n;
j = m;
lrc2 = lrc;
while (--i > mark) {
if (j == 0)
lrc2 = lrc2->down;
j = i & JSLRS_CHUNK_MASK;
if (lrc2->roots[j] == v)
break;
}
/* If we didn't find v in this scope, assert and bail out. */
JS_ASSERT(i != mark);
if (i == mark)
return;
/* Swap top and v so common tail code can pop v. */
lrc2->roots[j] = top;
}
/* Pop the last value from the stack. */
lrc->roots[m] = JSVAL_NULL;
lrs->rootCount = n;
if (m == 0) {
JS_ASSERT(n != 0);
JS_ASSERT(lrc != &lrs->firstChunk);
lrs->topChunk = lrc->down;
JS_free(cx, lrc);
}
}
int
js_PushLocalRoot(JSContext *cx, JSLocalRootStack *lrs, jsval v)
{
uint32 n, m;
JSLocalRootChunk *lrc;
n = lrs->rootCount;
m = n & JSLRS_CHUNK_MASK;
if (n == 0 || m != 0) {
/*
* At start of first chunk, or not at start of a non-first top chunk.
* Check for lrs->rootCount overflow.
*/
if ((uint32)(n + 1) == 0) {
JS_ReportErrorNumber(cx, js_GetErrorMessage, NULL,
JSMSG_TOO_MANY_LOCAL_ROOTS);
return -1;
}
lrc = lrs->topChunk;
JS_ASSERT(n != 0 || lrc == &lrs->firstChunk);
} else {
/*
* After lrs->firstChunk, trying to index at a power-of-two chunk
* boundary: need a new chunk.
*/
lrc = (JSLocalRootChunk *) JS_malloc(cx, sizeof *lrc);
if (!lrc)
return -1;
lrc->down = lrs->topChunk;
lrs->topChunk = lrc;
}
lrs->rootCount = n + 1;
lrc->roots[m] = v;
return (int) n;
}
void
js_MarkLocalRoots(JSContext *cx, JSLocalRootStack *lrs)
{
uint32 n, m, mark;
JSLocalRootChunk *lrc;
n = lrs->rootCount;
if (n == 0)
return;
mark = lrs->scopeMark;
lrc = lrs->topChunk;
do {
while (--n > mark) {
#ifdef GC_MARK_DEBUG
char name[22];
JS_snprintf(name, sizeof name, "<local root %u>", n);
#endif
m = n & JSLRS_CHUNK_MASK;
JS_ASSERT(JSVAL_IS_GCTHING(lrc->roots[m]));
GC_MARK(cx, JSVAL_TO_GCTHING(lrc->roots[m]), name);
if (m == 0)
lrc = lrc->down;
}
m = n & JSLRS_CHUNK_MASK;
mark = JSVAL_TO_INT(lrc->roots[m]);
if (m == 0)
lrc = lrc->down;
} while (n != 0);
JS_ASSERT(!lrc);
}
static void
ReportError(JSContext *cx, const char *message, JSErrorReport *reportp)
{
/*
* Check the error report, and set a JavaScript-catchable exception
* if the error is defined to have an associated exception. If an
* exception is thrown, then the JSREPORT_EXCEPTION flag will be set
* on the error report, and exception-aware hosts should ignore it.
*/
JS_ASSERT(reportp);
if (reportp->errorNumber == JSMSG_UNCAUGHT_EXCEPTION)
reportp->flags |= JSREPORT_EXCEPTION;
/*
* Call the error reporter only if an exception wasn't raised.
*
* If an exception was raised, then we call the debugErrorHook
* (if present) to give it a chance to see the error before it
* propagates out of scope. This is needed for compatability
* with the old scheme.
*/
if (!js_ErrorToException(cx, message, reportp)) {
js_ReportErrorAgain(cx, message, reportp);
} else if (cx->runtime->debugErrorHook && cx->errorReporter) {
JSDebugErrorHook hook = cx->runtime->debugErrorHook;
/* test local in case debugErrorHook changed on another thread */
if (hook)
hook(cx, message, reportp, cx->runtime->debugErrorHookData);
}
}
/*
* We don't post an exception in this case, since doing so runs into
* complications of pre-allocating an exception object which required
* running the Exception class initializer early etc.
* Instead we just invoke the errorReporter with an "Out Of Memory"
* type message, and then hope the process ends swiftly.
*/
void
js_ReportOutOfMemory(JSContext *cx)
{
JSStackFrame *fp;
JSErrorReport report;
JSErrorReporter onError = cx->errorReporter;
/* Get the message for this error, but we won't expand any arguments. */
const JSErrorFormatString *efs =
js_GetLocalizedErrorMessage(cx, NULL, NULL, JSMSG_OUT_OF_MEMORY);
const char *msg = efs ? efs->format : "Out of memory";
/* Fill out the report, but don't do anything that requires allocation. */
memset(&report, 0, sizeof (struct JSErrorReport));
report.flags = JSREPORT_ERROR;
report.errorNumber = JSMSG_OUT_OF_MEMORY;
/*
* Walk stack until we find a frame that is associated with some script
* rather than a native frame.
*/
for (fp = cx->fp; fp; fp = fp->down) {
if (fp->script && fp->pc) {
report.filename = fp->script->filename;
report.lineno = js_PCToLineNumber(cx, fp->script, fp->pc);
break;
}
}
/*
* If debugErrorHook is present then we give it a chance to veto
* sending the error on to the regular ErrorReporter.
*/
if (onError) {
JSDebugErrorHook hook = cx->runtime->debugErrorHook;
if (hook &&
!hook(cx, msg, &report, cx->runtime->debugErrorHookData)) {
onError = NULL;
}
}
if (onError)
onError(cx, msg, &report);
}
JSBool
js_ReportErrorVA(JSContext *cx, uintN flags, const char *format, va_list ap)
{
char *message;
jschar *ucmessage;
size_t messagelen;
JSStackFrame *fp;
JSErrorReport report;
JSBool warning;
if ((flags & JSREPORT_STRICT) && !JS_HAS_STRICT_OPTION(cx))
return JS_TRUE;
message = JS_vsmprintf(format, ap);
if (!message)
return JS_FALSE;
messagelen = strlen(message);
memset(&report, 0, sizeof (struct JSErrorReport));
report.flags = flags;
report.errorNumber = JSMSG_USER_DEFINED_ERROR;
report.ucmessage = ucmessage = js_InflateString(cx, message, &messagelen);
/* Find the top-most active script frame, for best line number blame. */
for (fp = cx->fp; fp; fp = fp->down) {
if (fp->script && fp->pc) {
report.filename = fp->script->filename;
report.lineno = js_PCToLineNumber(cx, fp->script, fp->pc);
break;
}
}
warning = JSREPORT_IS_WARNING(report.flags);
if (warning && JS_HAS_WERROR_OPTION(cx)) {
report.flags &= ~JSREPORT_WARNING;
warning = JS_FALSE;
}
ReportError(cx, message, &report);
free(message);
JS_free(cx, ucmessage);
return warning;
}
/*
* The arguments from ap need to be packaged up into an array and stored
* into the report struct.
*
* The format string addressed by the error number may contain operands
* identified by the format {N}, where N is a decimal digit. Each of these
* is to be replaced by the Nth argument from the va_list. The complete
* message is placed into reportp->ucmessage converted to a JSString.
*
* Returns true if the expansion succeeds (can fail if out of memory).
*/
JSBool
js_ExpandErrorArguments(JSContext *cx, JSErrorCallback callback,
void *userRef, const uintN errorNumber,
char **messagep, JSErrorReport *reportp,
JSBool *warningp, JSBool charArgs, va_list ap)
{
const JSErrorFormatString *efs;
int i;
int argCount;
*warningp = JSREPORT_IS_WARNING(reportp->flags);
if (*warningp && JS_HAS_WERROR_OPTION(cx)) {
reportp->flags &= ~JSREPORT_WARNING;
*warningp = JS_FALSE;
}
*messagep = NULL;
/* Most calls supply js_GetErrorMessage; if this is so, assume NULL. */
if (!callback || callback == js_GetErrorMessage)
efs = js_GetLocalizedErrorMessage(cx, userRef, NULL, errorNumber);
else
efs = callback(userRef, NULL, errorNumber);
if (efs) {
size_t totalArgsLength = 0;
size_t argLengths[10]; /* only {0} thru {9} supported */
argCount = efs->argCount;
JS_ASSERT(argCount <= 10);
if (argCount > 0) {
/*
* Gather the arguments into an array, and accumulate
* their sizes. We allocate 1 more than necessary and
* null it out to act as the caboose when we free the
* pointers later.
*/
reportp->messageArgs = (const jschar **)
JS_malloc(cx, sizeof(jschar *) * (argCount + 1));
if (!reportp->messageArgs)
return JS_FALSE;
reportp->messageArgs[argCount] = NULL;
for (i = 0; i < argCount; i++) {
if (charArgs) {
char *charArg = va_arg(ap, char *);
size_t charArgLength = strlen(charArg);