static JS::UniqueChars
FormatFrame(JSContext* cx, const FrameIter& iter, JS::UniqueChars&& inBuf, int num,
bool showArgs, bool showLocals, bool showThisProps)
{
MOZ_ASSERT(!cx->isExceptionPending());
RootedScript script(cx, iter.script());
jsbytecode* pc = iter.pc();
RootedObject envChain(cx, iter.environmentChain(cx));
JSAutoCompartment ac(cx, envChain);
const char* filename = script->filename();
unsigned lineno = PCToLineNumber(script, pc);
RootedFunction fun(cx, iter.maybeCallee(cx));
RootedString funname(cx);
if (fun)
funname = fun->displayAtom();
RootedValue thisVal(cx);
if (iter.hasUsableAbstractFramePtr() &&
iter.isFunctionFrame() &&
fun && !fun->isArrow() && !fun->isDerivedClassConstructor() &&
!(fun->isBoundFunction() && iter.isConstructing()))
{
if (!GetFunctionThis(cx, iter.abstractFramePtr(), &thisVal))
return nullptr;
}
// print the frame number and function name
JS::UniqueChars buf(Move(inBuf));
if (funname) {
JSAutoByteString funbytes;
char* str = funbytes.encodeLatin1(cx, funname);
if (!str)
return nullptr;
buf = sprintf_append(cx, Move(buf), "%d %s(", num, str);
} else if (fun) {
buf = sprintf_append(cx, Move(buf), "%d anonymous(", num);
} else {
buf = sprintf_append(cx, Move(buf), "%d <TOP LEVEL>", num);
}
if (!buf)
return nullptr;
if (showArgs && iter.hasArgs()) {
PositionalFormalParameterIter fi(script);
bool first = true;
for (unsigned i = 0; i < iter.numActualArgs(); i++) {
RootedValue arg(cx);
if (i < iter.numFormalArgs() && fi.closedOver()) {
arg = iter.callObj(cx).aliasedBinding(fi);
} else if (iter.hasUsableAbstractFramePtr()) {
if (script->analyzedArgsUsage() &&
script->argsObjAliasesFormals() &&
iter.hasArgsObj())
{
arg = iter.argsObj().arg(i);
} else {
arg = iter.unaliasedActual(i, DONT_CHECK_ALIASING);
}
} else {
arg = MagicValue(JS_OPTIMIZED_OUT);
}
JSAutoByteString valueBytes;
const char* value = FormatValue(cx, arg, valueBytes);
if (!value) {
if (cx->isThrowingOutOfMemory())
return nullptr;
cx->clearPendingException();
}
JSAutoByteString nameBytes;
const char* name = nullptr;
if (i < iter.numFormalArgs()) {
MOZ_ASSERT(fi.argumentSlot() == i);
if (!fi.isDestructured()) {
name = nameBytes.encodeLatin1(cx, fi.name());
if (!name)
return nullptr;
} else {
name = "(destructured parameter)";
}
fi++;
}
if (value) {
buf = sprintf_append(cx, Move(buf), "%s%s%s%s%s%s",
!first ? ", " : "",
name ? name :"",
name ? " = " : "",
arg.isString() ? "\"" : "",
value,
arg.isString() ? "\"" : "");
if (!buf)
return nullptr;
first = false;
} else {
buf = sprintf_append(cx, Move(buf),
" <Failed to get argument while inspecting stack frame>\n");
if (!buf)
return nullptr;
}
}
}
// print filename and line number
buf = sprintf_append(cx, Move(buf), "%s [\"%s\":%d]\n",
fun ? ")" : "",
filename ? filename : "<unknown>",
lineno);
if (!buf)
return nullptr;
// 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()) {
JSAutoByteString thisValBytes;
RootedString thisValStr(cx, ToString<CanGC>(cx, thisVal));
if (!thisValStr) {
if (cx->isThrowingOutOfMemory())
return nullptr;
cx->clearPendingException();
}
if (thisValStr) {
const char* str = thisValBytes.encodeLatin1(cx, thisValStr);
if (!str)
return nullptr;
buf = sprintf_append(cx, Move(buf), " this = %s\n", str);
} else {
buf = sprintf_append(cx, Move(buf), " <failed to get 'this' value>\n");
}
if (!buf)
return nullptr;
}
}
if (showThisProps && thisVal.isObject()) {
RootedObject obj(cx, &thisVal.toObject());
AutoIdVector keys(cx);
if (!GetPropertyKeys(cx, obj, JSITER_OWNONLY, &keys)) {
if (cx->isThrowingOutOfMemory())
return nullptr;
cx->clearPendingException();
}
RootedId id(cx);
for (size_t i = 0; i < keys.length(); i++) {
RootedId id(cx, keys[i]);
RootedValue key(cx, IdToValue(id));
RootedValue v(cx);
if (!GetProperty(cx, obj, obj, id, &v)) {
if (cx->isThrowingOutOfMemory())
return nullptr;
cx->clearPendingException();
buf = sprintf_append(cx, Move(buf),
" <Failed to fetch property while inspecting stack frame>\n");
if (!buf)
return nullptr;
continue;
}
JSAutoByteString nameBytes;
const char* name = FormatValue(cx, key, nameBytes);
if (!name) {
if (cx->isThrowingOutOfMemory())
return nullptr;
cx->clearPendingException();
}
JSAutoByteString valueBytes;
const char* value = FormatValue(cx, v, valueBytes);
if (!value) {
if (cx->isThrowingOutOfMemory())
return nullptr;
cx->clearPendingException();
}
if (name && value) {
buf = sprintf_append(cx, Move(buf), " this.%s = %s%s%s\n",
name,
v.isString() ? "\"" : "",
value,
v.isString() ? "\"" : "");
} else {
buf = sprintf_append(cx, Move(buf),
" <Failed to format values while inspecting stack frame>\n");
}
if (!buf)
return nullptr;
}
}
MOZ_ASSERT(!cx->isExceptionPending());
return buf;
}
