DXR is a code search and navigation tool aimed at making sense of large projects. It supports full-text and regex searches as well as structural queries.

Line Code
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544
/* -*- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
 * vim: set ts=4 sw=4 et tw=78:
 *
 * ***** 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 SpiderMonkey code.
 *
 * The Initial Developer of the Original Code is
 * Mozilla Corporation.
 * Portions created by the Initial Developer are Copyright (C) 2010
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *   Jeff Walden <jwalden+code@mit.edu> (original author)
 *
 * 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 ***** */

#ifndef jscntxtinlines_h___
#define jscntxtinlines_h___

#include "jscntxt.h"
#include "jscompartment.h"
#include "jsfriendapi.h"
#include "jsinterp.h"
#include "jsxml.h"
#include "jsgc.h"

#include "frontend/ParseMaps.h"
#include "vm/RegExpObject.h"

namespace js {

struct PreserveRegsGuard
{
    PreserveRegsGuard(JSContext *cx, FrameRegs &regs)
      : prevContextRegs(cx->maybeRegs()), cx(cx), regs_(regs) {
        cx->stack.repointRegs(&regs_);
    }
    ~PreserveRegsGuard() {
        JS_ASSERT(cx->maybeRegs() == &regs_);
        *prevContextRegs = regs_;
        cx->stack.repointRegs(prevContextRegs);
    }

    FrameRegs *prevContextRegs;

  private:
    JSContext *cx;
    FrameRegs &regs_;
};

static inline GlobalObject *
GetGlobalForScopeChain(JSContext *cx)
{
    /*
     * This is essentially GetScopeChain(cx)->getGlobal(), but without
     * falling off trace.
     *
     * This use of cx->fp, possibly on trace, is deliberate:
     * cx->fp->scopeChain->getGlobal() returns the same object whether we're on
     * trace or not, since we do not trace calls across global objects.
     */
    VOUCH_DOES_NOT_REQUIRE_STACK();

    if (cx->hasfp())
        return cx->fp()->scopeChain().getGlobal();

    JSObject *scope = JS_ObjectToInnerObject(cx, cx->globalObject);
    if (!scope)
        return NULL;
    return scope->asGlobal();
}

inline GSNCache *
GetGSNCache(JSContext *cx)
{
    return &JS_THREAD_DATA(cx)->gsnCache;
}

class AutoNamespaceArray : protected AutoGCRooter {
  public:
    AutoNamespaceArray(JSContext *cx) : AutoGCRooter(cx, NAMESPACES) {
        array.init();
    }

    ~AutoNamespaceArray() {
        array.finish(context);
    }

    uint32 length() const { return array.length; }

  public:
    friend void AutoGCRooter::trace(JSTracer *trc);

    JSXMLArray array;
};

#ifdef DEBUG
class CompartmentChecker
{
  private:
    JSContext *context;
    JSCompartment *compartment;

  public:
    explicit CompartmentChecker(JSContext *cx) : context(cx), compartment(cx->compartment) {
        check(cx->hasfp() ? JS_GetGlobalForScopeChain(cx) : cx->globalObject);
        VOUCH_DOES_NOT_REQUIRE_STACK();
    }

    /*
     * Set a breakpoint here (break js::CompartmentChecker::fail) to debug
     * compartment mismatches.
     */
    static void fail(JSCompartment *c1, JSCompartment *c2) {
        printf("*** Compartment mismatch %p vs. %p\n", (void *) c1, (void *) c2);
        JS_NOT_REACHED("compartment mismatched");
    }

    /* Note: should only be used when neither c1 nor c2 may be the default compartment. */
    static void check(JSCompartment *c1, JSCompartment *c2) {
        JS_ASSERT(c1 != c1->rt->atomsCompartment);
        JS_ASSERT(c2 != c2->rt->atomsCompartment);
        if (c1 != c2)
            fail(c1, c2);
    }

    void check(JSCompartment *c) {
        if (c && c != context->runtime->atomsCompartment) {
            if (!compartment)
                compartment = c;
            else if (c != compartment)
                fail(compartment, c);
        }
    }

    void check(JSPrincipals *) { /* nothing for now */ }

    void check(JSObject *obj) {
        if (obj)
            check(obj->compartment());
    }

    void check(JSString *str) {
        if (!str->isAtom())
            check(str->compartment());
    }

    void check(const js::Value &v) {
        if (v.isObject())
            check(&v.toObject());
        else if (v.isString())
            check(v.toString());
    }

    void check(const ValueArray &arr) {
        for (size_t i = 0; i < arr.length; i++)
            check(arr.array[i]);
    }

    void check(const JSValueArray &arr) {
        for (size_t i = 0; i < arr.length; i++)
            check(arr.array[i]);
    }

    void check(const CallArgs &args) {
        for (Value *p = args.base(); p != args.end(); ++p)
            check(*p);
    }

    void check(jsid id) {
        if (JSID_IS_OBJECT(id))
            check(JSID_TO_OBJECT(id));
    }
    
    void check(JSIdArray *ida) {
        if (ida) {
            for (jsint i = 0; i < ida->length; i++) {
                if (JSID_IS_OBJECT(ida->vector[i]))
                    check(ida->vector[i]);
            }
        }
    }

    void check(JSScript *script) {
        if (script) {
            check(script->compartment());
            if (!script->isCachedEval && script->u.globalObject)
                check(script->u.globalObject);
        }
    }

    void check(StackFrame *fp) {
        check(&fp->scopeChain());
    }
};

#endif

/*
 * Don't perform these checks when called from a finalizer. The checking
 * depends on other objects not having been swept yet.
 */
#define START_ASSERT_SAME_COMPARTMENT()                                       \
    if (cx->runtime->gcRunning)                                               \
        return;                                                               \
    CompartmentChecker c(cx)

template <class T1> inline void
assertSameCompartment(JSContext *cx, T1 t1)
{
#ifdef DEBUG
    START_ASSERT_SAME_COMPARTMENT();
    c.check(t1);
#endif
}

template <class T1, class T2> inline void
assertSameCompartment(JSContext *cx, T1 t1, T2 t2)
{
#ifdef DEBUG
    START_ASSERT_SAME_COMPARTMENT();
    c.check(t1);
    c.check(t2);
#endif
}

template <class T1, class T2, class T3> inline void
assertSameCompartment(JSContext *cx, T1 t1, T2 t2, T3 t3)
{
#ifdef DEBUG
    START_ASSERT_SAME_COMPARTMENT();
    c.check(t1);
    c.check(t2);
    c.check(t3);
#endif
}

template <class T1, class T2, class T3, class T4> inline void
assertSameCompartment(JSContext *cx, T1 t1, T2 t2, T3 t3, T4 t4)
{
#ifdef DEBUG
    START_ASSERT_SAME_COMPARTMENT();
    c.check(t1);
    c.check(t2);
    c.check(t3);
    c.check(t4);
#endif
}

template <class T1, class T2, class T3, class T4, class T5> inline void
assertSameCompartment(JSContext *cx, T1 t1, T2 t2, T3 t3, T4 t4, T5 t5)
{
#ifdef DEBUG
    START_ASSERT_SAME_COMPARTMENT();
    c.check(t1);
    c.check(t2);
    c.check(t3);
    c.check(t4);
    c.check(t5);
#endif
}

#undef START_ASSERT_SAME_COMPARTMENT

STATIC_PRECONDITION_ASSUME(ubound(args.argv_) >= argc)
JS_ALWAYS_INLINE bool
CallJSNative(JSContext *cx, Native native, const CallArgs &args)
{
#ifdef DEBUG
    JSBool alreadyThrowing = cx->isExceptionPending();
#endif
    assertSameCompartment(cx, args);
    bool ok = native(cx, args.length(), args.base());
    if (ok) {
        assertSameCompartment(cx, args.rval());
        JS_ASSERT_IF(!alreadyThrowing, !cx->isExceptionPending());
    }
    return ok;
}

extern JSBool CallOrConstructBoundFunction(JSContext *, uintN, js::Value *);

STATIC_PRECONDITION(ubound(args.argv_) >= argc)
JS_ALWAYS_INLINE bool
CallJSNativeConstructor(JSContext *cx, Native native, const CallArgs &args)
{
#ifdef DEBUG
    JSObject &callee = args.callee();
#endif

    JS_ASSERT(args.thisv().isMagic());
    if (!CallJSNative(cx, native, args))
        return false;

    /*
     * Native constructors must return non-primitive values on success.
     * Although it is legal, if a constructor returns the callee, there is a
     * 99.9999% chance it is a bug. If any valid code actually wants the
     * constructor to return the callee, the assertion can be removed or
     * (another) conjunct can be added to the antecedent.
     *
     * Proxies are exceptions to both rules: they can return primitives and
     * they allow content to return the callee.
     *
     * CallOrConstructBoundFunction is an exception as well because we
     * might have used bind on a proxy function.
     *
     * (new Object(Object)) returns the callee.
     */
    JS_ASSERT_IF(native != FunctionProxyClass.construct &&
                 native != CallableObjectClass.construct &&
                 native != js::CallOrConstructBoundFunction &&
                 (!callee.isFunction() || callee.getFunctionPrivate()->u.n.clasp != &ObjectClass),
                 !args.rval().isPrimitive() && callee != args.rval().toObject());

    return true;
}

JS_ALWAYS_INLINE bool
CallJSPropertyOp(JSContext *cx, PropertyOp op, JSObject *receiver, jsid id, Value *vp)
{
    assertSameCompartment(cx, receiver, id, *vp);
    JSBool ok = op(cx, receiver, id, vp);
    if (ok)
        assertSameCompartment(cx, receiver, *vp);
    return ok;
}

JS_ALWAYS_INLINE bool
CallJSPropertyOpSetter(JSContext *cx, StrictPropertyOp op, JSObject *obj, jsid id,
                       JSBool strict, Value *vp)
{
    assertSameCompartment(cx, obj, id, *vp);
    return op(cx, obj, id, strict, vp);
}

inline bool
CallSetter(JSContext *cx, JSObject *obj, jsid id, StrictPropertyOp op, uintN attrs,
           uintN shortid, JSBool strict, Value *vp)
{
    if (attrs & JSPROP_SETTER)
        return InvokeGetterOrSetter(cx, obj, CastAsObjectJsval(op), 1, vp, vp);

    if (attrs & JSPROP_GETTER)
        return js_ReportGetterOnlyAssignment(cx);

    if (attrs & JSPROP_SHORTID)
        id = INT_TO_JSID(shortid);
    return CallJSPropertyOpSetter(cx, op, obj, id, strict, vp);
}

#ifdef JS_TRACER
/*
 * Reconstruct the JS stack and clear cx->tracecx. We must be currently in a
 * _FAIL builtin from trace on cx or another context on the same thread. The
 * machine code for the trace remains on the C stack when js_DeepBail returns.
 *
 * Implemented in jstracer.cpp.
 */
JS_FORCES_STACK JS_FRIEND_API(void)
DeepBail(JSContext *cx);
#endif

static JS_INLINE void
LeaveTraceIfGlobalObject(JSContext *cx, JSObject *obj)
{
    if (!obj->getParent())
        LeaveTrace(cx);
}

static JS_INLINE void
LeaveTraceIfArgumentsObject(JSContext *cx, JSObject *obj)
{
    if (obj->isArguments())
        LeaveTrace(cx);
}

static inline JSAtom **
FrameAtomBase(JSContext *cx, js::StackFrame *fp)
{
    return fp->hasImacropc()
           ? cx->runtime->atomState.commonAtomsStart()
           : fp->script()->atoms;
}

}  /* namespace js */

inline JSVersion
JSContext::findVersion() const
{
    if (hasVersionOverride)
        return versionOverride;

    if (stack.hasfp()) {
        /* There may be a scripted function somewhere on the stack! */
        js::StackFrame *f = fp();
        while (f && !f->isScriptFrame())
            f = f->prev();
        if (f)
            return f->script()->getVersion();
    }

    return defaultVersion;
}

inline bool
JSContext::canSetDefaultVersion() const
{
    return !stack.hasfp() && !hasVersionOverride;
}

inline void
JSContext::overrideVersion(JSVersion newVersion)
{
    JS_ASSERT(!canSetDefaultVersion());
    versionOverride = newVersion;
    hasVersionOverride = true;
}

inline bool
JSContext::maybeOverrideVersion(JSVersion newVersion)
{
    if (canSetDefaultVersion()) {
        setDefaultVersion(newVersion);
        return false;
    }
    overrideVersion(newVersion);
    return true;
}

inline uintN
JSContext::getCompileOptions() const { return js::VersionFlagsToOptions(findVersion()); }

inline uintN
JSContext::allOptions() const { return getRunOptions() | getCompileOptions(); }

inline void
JSContext::setCompileOptions(uintN newcopts)
{
    JS_ASSERT((newcopts & JSCOMPILEOPTION_MASK) == newcopts);
    if (JS_LIKELY(getCompileOptions() == newcopts))
        return;
    JSVersion version = findVersion();
    JSVersion newVersion = js::OptionFlagsToVersion(newcopts, version);
    maybeOverrideVersion(newVersion);
}

inline void
JSContext::assertValidStackDepth(uintN depth)
{
#ifdef DEBUG
    JS_ASSERT(0 <= regs().sp - fp()->base());
    JS_ASSERT(depth <= uintptr_t(regs().sp - fp()->base()));
#endif
}

#ifdef JS_METHODJIT
inline js::mjit::JaegerCompartment *JSContext::jaegerCompartment()
{
    return compartment->jaegerCompartment();
}
#endif

inline js::LifoAlloc &
JSContext::typeLifoAlloc()
{
    return compartment->typeLifoAlloc;
}

inline bool
JSContext::ensureGeneratorStackSpace()
{
    bool ok = genStack.reserve(genStack.length() + 1);
    if (!ok)
        js_ReportOutOfMemory(this);
    return ok;
}

inline js::RegExpStatics *
JSContext::regExpStatics()
{
    return js::GetGlobalForScopeChain(this)->getRegExpStatics();
}

inline void
JSContext::setPendingException(js::Value v) {
    this->throwing = true;
    this->exception = v;
    js::assertSameCompartment(this, v);
}

inline bool
JSContext::ensureParseMapPool()
{
    if (parseMapPool_)
        return true;
    parseMapPool_ = js::OffTheBooks::new_<js::ParseMapPool>(this);
    return parseMapPool_;
}

/*
 * Get the current frame, first lazily instantiating stack frames if needed.
 * (Do not access cx->fp() directly except in JS_REQUIRES_STACK code.)
 *
 * LeaveTrace is defined in jstracer.cpp if JS_TRACER is defined.
 */
static JS_FORCES_STACK JS_INLINE js::StackFrame *
js_GetTopStackFrame(JSContext *cx, FrameExpandKind expand)
{
    js::LeaveTrace(cx);

#ifdef JS_METHODJIT
    if (expand)
        js::mjit::ExpandInlineFrames(cx->compartment);
#endif

    return cx->maybefp();
}

#endif /* jscntxtinlines_h___ */