Source code
Revision control
Copy as Markdown
Other Tools
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
* vim: set ts=8 sts=2 et sw=2 tw=80:
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
#include "js/friend/DumpFunctions.h"
#include "mozilla/Maybe.h" // mozilla::Maybe
#include <inttypes.h> // PRIu64
#include <stddef.h> // size_t
#include <stdio.h> // fprintf, fflush
#include "jsfriendapi.h" // js::WeakMapTracer
#include "jstypes.h" // JS_PUBLIC_API
#include "gc/Cell.h" // js::gc::Cell, js::gc::TenuredCell
#include "gc/GC.h" // js::TraceRuntimeWithoutEviction
#include "gc/GCEnum.h" // js::CanGC
#include "gc/Heap.h" // js::gc::Arena
#include "gc/Tracer.h" // js::TraceChildren
#include "gc/WeakMap.h" // js::IterateHeapUnbarriered, js::WeakMapBase
#include "js/CallAndConstruct.h" // JS::IsCallable
#include "js/ColumnNumber.h" // JS::LimitedColumnNumberOneOrigin
#include "js/GCAPI.h" // JS::GCReason
#include "js/GCVector.h" // JS::RootedVector
#include "js/HeapAPI.h" // JS::GCCellPtr, js::gc::IsInsideNursery
#include "js/Id.h" // JS::PropertyKey
#include "js/Printer.h" // js::GenericPrinter, js::QuoteString, js::Sprinter
#include "js/RootingAPI.h" // JS::Handle, JS::Rooted
#include "js/TracingAPI.h" // JS::CallbackTracer, JS_GetTraceThingInfo
#include "js/UbiNode.h" // JS::ubi::Node
#include "js/Value.h" // JS::Value
#include "js/Wrapper.h" // js::UncheckedUnwrapWithoutExpose
#include "vm/BigIntType.h" // JS::BigInt::dump
#include "vm/FrameIter.h" // js::AllFramesIter, js::FrameIter
#include "vm/Interpreter.h" // GetFunctionThis
#include "vm/JSContext.h" // JSContext
#include "vm/JSFunction.h" // JSFunction
#include "vm/JSObject.h" // JSObject
#include "vm/JSScript.h" // JSScript
#include "vm/Realm.h" // JS::Realm
#include "vm/Runtime.h" // JSRuntime
#include "vm/Scope.h" // js::PositionalFormalParameterIter
#include "vm/Stack.h" // js::DONT_CHECK_ALIASING
#include "vm/StringType.h" // JSAtom, JSString, js::ToString
#include "vm/JSObject-inl.h" // js::IsCallable
#include "vm/Realm-inl.h" // js::AutoRealm
namespace JS {
class JS_PUBLIC_API AutoRequireNoGC;
class JS_PUBLIC_API Zone;
} // namespace JS
using JS::Handle;
using JS::MagicValue;
using JS::PropertyKey;
using JS::Realm;
using JS::Rooted;
using JS::RootedVector;
using JS::UniqueChars;
using JS::Value;
using JS::Zone;
using js::AllFramesIter;
using js::AutoRealm;
using js::CanGC;
using js::DONT_CHECK_ALIASING;
using js::FrameIter;
using js::PositionalFormalParameterIter;
using js::Sprinter;
using js::ToString;
using js::UncheckedUnwrapWithoutExpose;
using js::WeakMapTracer;
// We don't want jsfriendapi.h to depend on GenericPrinter,
// so these functions are declared directly in the cpp.
namespace js {
class InterpreterFrame;
extern JS_PUBLIC_API void DumpString(JSString* str, GenericPrinter& out);
extern JS_PUBLIC_API void DumpAtom(JSAtom* atom, GenericPrinter& out);
extern JS_PUBLIC_API void DumpObject(JSObject* obj, GenericPrinter& out);
extern JS_PUBLIC_API void DumpChars(const char16_t* s, size_t n,
GenericPrinter& out);
extern JS_PUBLIC_API void DumpValue(const JS::Value& val, GenericPrinter& out);
extern JS_PUBLIC_API void DumpId(PropertyKey id, GenericPrinter& out);
extern JS_PUBLIC_API void DumpInterpreterFrame(
JSContext* cx, GenericPrinter& out, InterpreterFrame* start = nullptr);
extern JS_PUBLIC_API void DumpBigInt(JS::BigInt* bi, GenericPrinter& out);
} // namespace js
void js::DumpString(JSString* str, GenericPrinter& out) {
#if defined(DEBUG) || defined(JS_JITSPEW)
str->dump(out);
#endif
}
void js::DumpAtom(JSAtom* atom, GenericPrinter& out) {
#if defined(DEBUG) || defined(JS_JITSPEW)
atom->dump(out);
#endif
}
void js::DumpChars(const char16_t* s, size_t n, GenericPrinter& out) {
#if defined(DEBUG) || defined(JS_JITSPEW)
if (n == SIZE_MAX) {
n = 0;
while (s[n]) {
n++;
}
}
out.printf("char16_t * (%p) = \"", (void*)s);
JSString::dumpCharsNoQuote(s, n, out);
out.put("\"\n");
#endif
}
void js::DumpObject(JSObject* obj, GenericPrinter& out) {
#if defined(DEBUG) || defined(JS_JITSPEW)
if (!obj) {
out.printf("NULL\n");
return;
}
obj->dump(out);
#endif
}
void js::DumpBigInt(JS::BigInt* bi, GenericPrinter& out) {
#if defined(DEBUG) || defined(JS_JITSPEW)
bi->dump(out);
#endif
}
void js::DumpString(JSString* str, FILE* fp) {
#if defined(DEBUG) || defined(JS_JITSPEW)
Fprinter out(fp);
js::DumpString(str, out);
#endif
}
void js::DumpAtom(JSAtom* atom, FILE* fp) {
#if defined(DEBUG) || defined(JS_JITSPEW)
Fprinter out(fp);
js::DumpAtom(atom, out);
#endif
}
void js::DumpChars(const char16_t* s, size_t n, FILE* fp) {
#if defined(DEBUG) || defined(JS_JITSPEW)
Fprinter out(fp);
js::DumpChars(s, n, out);
#endif
}
void js::DumpObject(JSObject* obj, FILE* fp) {
#if defined(DEBUG) || defined(JS_JITSPEW)
Fprinter out(fp);
js::DumpObject(obj, out);
#endif
}
void js::DumpBigInt(JS::BigInt* bi, FILE* fp) {
#if defined(DEBUG) || defined(JS_JITSPEW)
Fprinter out(fp);
js::DumpBigInt(bi, out);
#endif
}
void js::DumpId(PropertyKey id, FILE* fp) {
#if defined(DEBUG) || defined(JS_JITSPEW)
Fprinter out(fp);
js::DumpId(id, out);
#endif
}
void js::DumpValue(const JS::Value& val, FILE* fp) {
#if defined(DEBUG) || defined(JS_JITSPEW)
Fprinter out(fp);
js::DumpValue(val, out);
#endif
}
void js::DumpString(JSString* str) { DumpString(str, stderr); }
void js::DumpAtom(JSAtom* atom) { DumpAtom(atom, stderr); }
void js::DumpObject(JSObject* obj) { DumpObject(obj, stderr); }
void js::DumpChars(const char16_t* s, size_t n) { DumpChars(s, n, stderr); }
void js::DumpBigInt(JS::BigInt* bi) { DumpBigInt(bi, stderr); }
void js::DumpValue(const JS::Value& val) { DumpValue(val, stderr); }
void js::DumpId(PropertyKey id) { DumpId(id, stderr); }
void js::DumpInterpreterFrame(JSContext* cx, InterpreterFrame* start) {
#if defined(DEBUG) || defined(JS_JITSPEW)
Fprinter out(stderr);
DumpInterpreterFrame(cx, out, start);
#endif
}
bool js::DumpPC(JSContext* cx) {
#if defined(DEBUG) || defined(JS_JITSPEW)
return DumpPC(cx, stdout);
#else
return true;
#endif
}
bool js::DumpScript(JSContext* cx, JSScript* scriptArg) {
#if defined(DEBUG) || defined(JS_JITSPEW)
return DumpScript(cx, scriptArg, stdout);
#else
return true;
#endif
}
static const char* FormatValue(JSContext* cx, Handle<Value> v,
UniqueChars& bytes) {
if (v.isMagic()) {
MOZ_ASSERT(v.whyMagic() == JS_OPTIMIZED_OUT ||
v.whyMagic() == JS_UNINITIALIZED_LEXICAL);
return "[unavailable]";
}
if (js::IsCallable(v)) {
return "[function]";
}
if (v.isObject() && js::IsCrossCompartmentWrapper(&v.toObject())) {
return "[cross-compartment wrapper]";
}
JSString* str;
{
mozilla::Maybe<AutoRealm> ar;
if (v.isObject()) {
ar.emplace(cx, &v.toObject());
}
str = ToString<CanGC>(cx, v);
if (!str) {
return nullptr;
}
}
bytes = js::QuoteString(cx, str, '"');
return bytes.get();
}
static bool FormatFrame(JSContext* cx, const FrameIter& iter, Sprinter& sp,
int num, bool showArgs, bool showLocals,
bool showThisProps) {
MOZ_ASSERT(!cx->isExceptionPending());
Rooted<JSScript*> script(cx, iter.script());
jsbytecode* pc = iter.pc();
Rooted<JSObject*> envChain(cx, iter.environmentChain(cx));
JSAutoRealm ar(cx, envChain);
const char* filename = script->filename();
JS::LimitedColumnNumberOneOrigin column;
unsigned lineno = PCToLineNumber(script, pc, &column);
Rooted<JSFunction*> fun(cx, iter.maybeCallee(cx));
Rooted<JSString*> funname(cx);
if (fun) {
funname = fun->fullDisplayAtom();
}
Rooted<Value> thisVal(cx);
if (iter.hasUsableAbstractFramePtr() && iter.isFunctionFrame() && fun &&
!fun->isArrow() && !fun->isDerivedClassConstructor()) {
if (!GetFunctionThis(cx, iter.abstractFramePtr(), &thisVal)) {
return false;
}
}
// print the frame number and function name
if (funname) {
UniqueChars funbytes = js::QuoteString(cx, funname);
if (!funbytes) {
return false;
}
sp.printf("%d %s(", num, funbytes.get());
} else if (fun) {
sp.printf("%d anonymous(", num);
} else {
sp.printf("%d <TOP LEVEL>", num);
}
if (showArgs && iter.hasArgs()) {
PositionalFormalParameterIter fi(script);
bool first = true;
for (unsigned i = 0; i < iter.numActualArgs(); i++) {
Rooted<Value> arg(cx);
if (i < iter.numFormalArgs() && fi.closedOver()) {
if (iter.hasInitialEnvironment(cx)) {
arg = iter.callObj(cx).aliasedBinding(fi);
} else {
arg = MagicValue(JS_OPTIMIZED_OUT);
}
} else if (iter.hasUsableAbstractFramePtr()) {
if (script->argsObjAliasesFormals() && iter.hasArgsObj()) {
arg = iter.argsObj().arg(i);
} else {
arg = iter.unaliasedActual(i, DONT_CHECK_ALIASING);
}
} else {
arg = MagicValue(JS_OPTIMIZED_OUT);
}
UniqueChars valueBytes;
const char* value = FormatValue(cx, arg, valueBytes);
if (!value) {
if (cx->isThrowingOutOfMemory()) {
return false;
}
cx->clearPendingException();
}
UniqueChars nameBytes;
const char* name = nullptr;
if (i < iter.numFormalArgs()) {
MOZ_ASSERT(fi.argumentSlot() == i);
if (!fi.isDestructured()) {
nameBytes = StringToNewUTF8CharsZ(cx, *fi.name());
name = nameBytes.get();
if (!name) {
return false;
}
} else {
name = "(destructured parameter)";
}
fi++;
}
if (value) {
sp.printf("%s%s%s%s%s%s", !first ? ", " : "", name ? name : "",
name ? " = " : "", arg.isString() ? "\"" : "", value,
arg.isString() ? "\"" : "");
first = false;
} else {
sp.put(
" <Failed to get argument while inspecting stack "
"frame>\n");
}
}
}
// print filename, line number and column
sp.printf("%s [\"%s\":%u:%u]\n", fun ? ")" : "",
filename ? filename : "<unknown>", lineno, column.oneOriginValue());
// Note: Right now we don't dump the local variables anymore, because
// that is hard to support across all the JITs etc.
// print the value of 'this'
if (showLocals) {
if (!thisVal.isUndefined()) {
Rooted<JSString*> thisValStr(cx, ToString<CanGC>(cx, thisVal));
if (!thisValStr) {
if (cx->isThrowingOutOfMemory()) {
return false;
}
cx->clearPendingException();
}
if (thisValStr) {
UniqueChars thisValBytes = QuoteString(cx, thisValStr);
if (!thisValBytes) {
return false;
}
sp.printf(" this = %s\n", thisValBytes.get());
} else {
sp.put(" <failed to get 'this' value>\n");
}
}
}
if (showThisProps && thisVal.isObject()) {
Rooted<JSObject*> obj(cx, &thisVal.toObject());
RootedVector<PropertyKey> keys(cx);
if (!GetPropertyKeys(cx, obj, JSITER_OWNONLY, &keys)) {
if (cx->isThrowingOutOfMemory()) {
return false;
}
cx->clearPendingException();
}
for (size_t i = 0; i < keys.length(); i++) {
Rooted<jsid> id(cx, keys[i]);
Rooted<Value> key(cx, IdToValue(id));
Rooted<Value> v(cx);
if (!GetProperty(cx, obj, obj, id, &v)) {
if (cx->isThrowingOutOfMemory()) {
return false;
}
cx->clearPendingException();
sp.put(
" <Failed to fetch property while inspecting stack "
"frame>\n");
continue;
}
UniqueChars nameBytes;
const char* name = FormatValue(cx, key, nameBytes);
if (!name) {
if (cx->isThrowingOutOfMemory()) {
return false;
}
cx->clearPendingException();
}
UniqueChars valueBytes;
const char* value = FormatValue(cx, v, valueBytes);
if (!value) {
if (cx->isThrowingOutOfMemory()) {
return false;
}
cx->clearPendingException();
}
if (name && value) {
sp.printf(" this.%s = %s%s%s\n", name, v.isString() ? "\"" : "",
value, v.isString() ? "\"" : "");
} else {
sp.put(
" <Failed to format values while inspecting stack "
"frame>\n");
}
}
}
MOZ_ASSERT(!cx->isExceptionPending());
return true;
}
static bool FormatWasmFrame(JSContext* cx, const FrameIter& iter, Sprinter& sp,
int num) {
UniqueChars nameStr;
if (JSAtom* functionDisplayAtom = iter.maybeFunctionDisplayAtom()) {
nameStr = StringToNewUTF8CharsZ(cx, *functionDisplayAtom);
if (!nameStr) {
return false;
}
}
sp.printf("%d %s()", num, nameStr ? nameStr.get() : "<wasm-function>");
sp.printf(" [\"%s\":wasm-function[%u]:0x%x]\n",
iter.filename() ? iter.filename() : "<unknown>",
iter.wasmFuncIndex(), iter.wasmBytecodeOffset());
MOZ_ASSERT(!cx->isExceptionPending());
return true;
}
JS::UniqueChars JS::FormatStackDump(JSContext* cx, bool showArgs,
bool showLocals, bool showThisProps) {
int num = 0;
Sprinter sp(cx);
if (!sp.init()) {
return nullptr;
}
for (AllFramesIter i(cx); !i.done(); ++i) {
bool ok = i.hasScript() ? FormatFrame(cx, i, sp, num, showArgs, showLocals,
showThisProps)
: FormatWasmFrame(cx, i, sp, num);
if (!ok) {
return nullptr;
}
num++;
}
if (num == 0) {
sp.put("JavaScript stack is empty\n");
}
return sp.release();
}
struct DumpHeapTracer final : public JS::CallbackTracer, public WeakMapTracer {
const char* prefix;
FILE* output;
mozilla::MallocSizeOf mallocSizeOf;
DumpHeapTracer(FILE* fp, JSContext* cx, mozilla::MallocSizeOf mallocSizeOf)
: JS::CallbackTracer(cx, JS::TracerKind::Callback,
JS::WeakMapTraceAction::Skip),
WeakMapTracer(cx->runtime()),
prefix(""),
output(fp),
mallocSizeOf(mallocSizeOf) {}
private:
void trace(JSObject* map, JS::GCCellPtr key, JS::GCCellPtr value) override {
JSObject* kdelegate = nullptr;
if (key.is<JSObject>()) {
kdelegate = UncheckedUnwrapWithoutExpose(&key.as<JSObject>());
}
fprintf(output, "WeakMapEntry map=%p key=%p keyDelegate=%p value=%p\n", map,
key.asCell(), kdelegate, value.asCell());
}
void onChild(JS::GCCellPtr thing, const char* name) override;
};
static char MarkDescriptor(js::gc::Cell* thing) {
js::gc::TenuredCell* cell = &thing->asTenured();
if (cell->isMarkedBlack()) {
return 'B';
}
if (cell->isMarkedGray()) {
return 'G';
}
if (cell->isMarkedAny()) {
return 'X';
}
return 'W';
}
static void DumpHeapVisitZone(JSRuntime* rt, void* data, Zone* zone,
const JS::AutoRequireNoGC& nogc) {
DumpHeapTracer* dtrc = static_cast<DumpHeapTracer*>(data);
fprintf(dtrc->output, "# zone %p\n", static_cast<void*>(zone));
}
static void DumpHeapVisitRealm(JSContext* cx, void* data, Realm* realm,
const JS::AutoRequireNoGC& nogc) {
char name[1024];
if (auto nameCallback = cx->runtime()->realmNameCallback) {
nameCallback(cx, realm, name, sizeof(name), nogc);
} else {
strcpy(name, "<unknown>");
}
DumpHeapTracer* dtrc = static_cast<DumpHeapTracer*>(data);
fprintf(dtrc->output, "# realm %s [in compartment %p, zone %p]\n", name,
static_cast<void*>(realm->compartment()),
static_cast<void*>(realm->zone()));
}
static void DumpHeapVisitArena(JSRuntime* rt, void* data, js::gc::Arena* arena,
JS::TraceKind traceKind, size_t thingSize,
const JS::AutoRequireNoGC& nogc) {
DumpHeapTracer* dtrc = static_cast<DumpHeapTracer*>(data);
fprintf(dtrc->output, "# arena allockind=%u size=%u\n",
unsigned(arena->getAllocKind()), unsigned(thingSize));
}
static void DumpHeapVisitCell(JSRuntime* rt, void* data, JS::GCCellPtr cellptr,
size_t thingSize,
const JS::AutoRequireNoGC& nogc) {
DumpHeapTracer* dtrc = static_cast<DumpHeapTracer*>(data);
char cellDesc[1024 * 32];
js::gc::GetTraceThingInfo(cellDesc, sizeof(cellDesc), cellptr.asCell(),
cellptr.kind(), true);
fprintf(dtrc->output, "%p %c %s", cellptr.asCell(),
MarkDescriptor(cellptr.asCell()), cellDesc);
if (dtrc->mallocSizeOf) {
auto size = JS::ubi::Node(cellptr).size(dtrc->mallocSizeOf);
fprintf(dtrc->output, " SIZE:: %" PRIu64 "\n", size);
} else {
fprintf(dtrc->output, "\n");
}
JS::TraceChildren(dtrc, cellptr);
}
void DumpHeapTracer::onChild(JS::GCCellPtr thing, const char* name) {
if (js::gc::IsInsideNursery(thing.asCell())) {
return;
}
char buffer[1024];
context().getEdgeName(name, buffer, sizeof(buffer));
fprintf(output, "%s%p %c %s\n", prefix, thing.asCell(),
MarkDescriptor(thing.asCell()), buffer);
}
void js::DumpHeap(JSContext* cx, FILE* fp,
DumpHeapNurseryBehaviour nurseryBehaviour,
mozilla::MallocSizeOf mallocSizeOf) {
if (nurseryBehaviour == CollectNurseryBeforeDump) {
cx->runtime()->gc.evictNursery(JS::GCReason::API);
}
DumpHeapTracer dtrc(fp, cx, mallocSizeOf);
fprintf(dtrc.output, "# Roots.\n");
TraceRuntimeWithoutEviction(&dtrc);
fprintf(dtrc.output, "# Weak maps.\n");
WeakMapBase::traceAllMappings(&dtrc);
fprintf(dtrc.output, "==========\n");
dtrc.prefix = "> ";
IterateHeapUnbarriered(cx, &dtrc, DumpHeapVisitZone, DumpHeapVisitRealm,
DumpHeapVisitArena, DumpHeapVisitCell);
fflush(dtrc.output);
}
void DumpFmtV(FILE* fp, const char* fmt, va_list args) {
js::Fprinter out(fp);
out.vprintf(fmt, args);
}
void js::DumpFmt(FILE* fp, const char* fmt, ...) {
va_list args;
va_start(args, fmt);
DumpFmtV(fp, fmt, args);
va_end(args);
}
void js::DumpFmt(const char* fmt, ...) {
va_list args;
va_start(args, fmt);
DumpFmtV(stderr, fmt, args);
va_end(args);
}