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/* -*- 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 "vm/ErrorReporting.h"
#include <stdarg.h>
#include <utility>
#include "jsexn.h"
#include "jsfriendapi.h"
#include "frontend/FrontendContext.h" // AutoReportFrontendContext
#include "js/CharacterEncoding.h" // JS::ConstUTF8CharsZ
#include "js/ColumnNumber.h" // JS::ColumnNumberOneOrigin, JS::TaggedColumnNumberOneOrigin
#include "js/ErrorReport.h" // JSErrorBase
#include "js/friend/ErrorMessages.h" // js::GetErrorMessage, JSMSG_*
#include "js/Printf.h" // JS_vsmprintf
#include "js/Warnings.h" // JS::WarningReporter
#include "vm/FrameIter.h"
#include "vm/GlobalObject.h"
#include "vm/JSContext.h"
using namespace js;
using JS::HandleObject;
using JS::HandleValue;
using JS::UniqueTwoByteChars;
void js::CallWarningReporter(JSContext* cx, JSErrorReport* reportp) {
MOZ_ASSERT(reportp->isWarning());
if (JS::WarningReporter warningReporter = cx->runtime()->warningReporter) {
warningReporter(cx, reportp);
}
}
bool js::CompileError::throwError(JSContext* cx) {
if (isWarning()) {
CallWarningReporter(cx, this);
return true;
}
// If there's a runtime exception type associated with this error
// number, set that as the pending exception. For errors occurring at
// compile time, this is very likely to be a JSEXN_SYNTAXERR.
return ErrorToException(cx, this, nullptr, nullptr);
}
bool js::ReportExceptionClosure::operator()(JSContext* cx) {
cx->setPendingException(exn_, ShouldCaptureStack::Always);
return false;
}
bool js::ReportCompileWarning(FrontendContext* fc, ErrorMetadata&& metadata,
UniquePtr<JSErrorNotes> notes,
unsigned errorNumber, va_list* args) {
// On the main thread, report the error immediately. When compiling off
// thread, save the error so that the thread finishing the parse can report
// it later.
CompileError err;
err.notes = std::move(notes);
err.isWarning_ = true;
err.errorNumber = errorNumber;
err.filename = JS::ConstUTF8CharsZ(metadata.filename);
err.lineno = metadata.lineNumber;
err.column = metadata.columnNumber;
err.isMuted = metadata.isMuted;
if (UniqueTwoByteChars lineOfContext = std::move(metadata.lineOfContext)) {
err.initOwnedLinebuf(lineOfContext.release(), metadata.lineLength,
metadata.tokenOffset);
}
if (!ExpandErrorArgumentsVA(fc, GetErrorMessage, nullptr, errorNumber,
ArgumentsAreLatin1, &err, *args)) {
return false;
}
return fc->reportWarning(std::move(err));
}
static void ReportCompileErrorImpl(FrontendContext* fc,
js::ErrorMetadata&& metadata,
js::UniquePtr<JSErrorNotes> notes,
unsigned errorNumber, va_list* args,
ErrorArgumentsType argumentsType) {
js::CompileError err;
err.notes = std::move(notes);
err.isWarning_ = false;
err.errorNumber = errorNumber;
err.filename = JS::ConstUTF8CharsZ(metadata.filename);
err.lineno = metadata.lineNumber;
err.column = metadata.columnNumber;
err.isMuted = metadata.isMuted;
if (UniqueTwoByteChars lineOfContext = std::move(metadata.lineOfContext)) {
err.initOwnedLinebuf(lineOfContext.release(), metadata.lineLength,
metadata.tokenOffset);
}
if (!js::ExpandErrorArgumentsVA(fc, js::GetErrorMessage, nullptr, errorNumber,
argumentsType, &err, *args)) {
return;
}
fc->reportError(std::move(err));
}
void js::ReportCompileErrorLatin1(FrontendContext* fc, ErrorMetadata&& metadata,
UniquePtr<JSErrorNotes> notes,
unsigned errorNumber, ...) {
va_list args;
va_start(args, errorNumber);
ReportCompileErrorLatin1VA(fc, std::move(metadata), std::move(notes),
errorNumber, &args);
va_end(args);
}
void js::ReportCompileErrorUTF8(FrontendContext* fc, ErrorMetadata&& metadata,
UniquePtr<JSErrorNotes> notes,
unsigned errorNumber, ...) {
va_list args;
va_start(args, errorNumber);
ReportCompileErrorUTF8VA(fc, std::move(metadata), std::move(notes),
errorNumber, &args);
va_end(args);
}
void js::ReportCompileErrorLatin1VA(FrontendContext* fc,
ErrorMetadata&& metadata,
UniquePtr<JSErrorNotes> notes,
unsigned errorNumber, va_list* args) {
ReportCompileErrorImpl(fc, std::move(metadata), std::move(notes), errorNumber,
args, ArgumentsAreLatin1);
}
void js::ReportCompileErrorUTF8VA(FrontendContext* fc, ErrorMetadata&& metadata,
UniquePtr<JSErrorNotes> notes,
unsigned errorNumber, va_list* args) {
ReportCompileErrorImpl(fc, std::move(metadata), std::move(notes), errorNumber,
args, ArgumentsAreUTF8);
}
void js::ReportErrorToGlobal(JSContext* cx, Handle<GlobalObject*> global,
HandleValue error) {
MOZ_ASSERT(!cx->isExceptionPending());
#ifdef DEBUG
// No assertSameCompartment version that doesn't take JSContext...
if (error.isObject()) {
AssertSameCompartment(global, &error.toObject());
}
#endif // DEBUG
js::ReportExceptionClosure report(error);
PrepareScriptEnvironmentAndInvoke(cx, global, report);
}
static bool ReportError(JSContext* cx, JSErrorReport* reportp,
JSErrorCallback callback, void* userRef) {
if (reportp->isWarning()) {
CallWarningReporter(cx, reportp);
return true;
}
// Check the error report, and set a JavaScript-catchable exception
// if the error is defined to have an associated exception.
return ErrorToException(cx, reportp, callback, userRef);
}
/*
* The given JSErrorReport object have been zeroed and must not outlive
* cx->fp() (otherwise owned fields may become invalid).
*/
static void PopulateReportBlame(JSContext* cx, JSErrorReport* report) {
JS::Realm* realm = cx->realm();
if (!realm) {
return;
}
/*
* Walk stack until we find a frame that is associated with a non-builtin
* rather than a builtin frame and which we're allowed to know about.
*/
NonBuiltinFrameIter iter(cx, realm->principals());
if (iter.done()) {
return;
}
report->filename = JS::ConstUTF8CharsZ(iter.filename());
if (iter.hasScript()) {
report->sourceId = iter.script()->scriptSource()->id();
}
JS::TaggedColumnNumberOneOrigin column;
report->lineno = iter.computeLine(&column);
report->column = JS::ColumnNumberOneOrigin(column.oneOriginValue());
report->isMuted = iter.mutedErrors();
}
class MOZ_RAII AutoMessageArgs {
size_t totalLength_;
/* only {0} thru {9} supported */
mozilla::Array<const char*, JS::MaxNumErrorArguments> args_;
mozilla::Array<size_t, JS::MaxNumErrorArguments> lengths_;
uint16_t count_;
bool allocatedElements_ : 1;
public:
AutoMessageArgs() : totalLength_(0), count_(0), allocatedElements_(false) {
PodArrayZero(args_);
}
~AutoMessageArgs() {
/* free the arguments only if we allocated them */
if (allocatedElements_) {
uint16_t i = 0;
while (i < count_) {
if (args_[i]) {
js_free((void*)args_[i]);
}
i++;
}
}
}
const char* args(size_t i) const {
MOZ_ASSERT(i < count_);
return args_[i];
}
size_t totalLength() const { return totalLength_; }
size_t lengths(size_t i) const {
MOZ_ASSERT(i < count_);
return lengths_[i];
}
uint16_t count() const { return count_; }
/* Gather the arguments into an array, and accumulate their sizes.
*
* We could template on the type of argsArg, but we're already trusting people
* to do the right thing with varargs, so might as well trust them on this
* part too. Upstream consumers do assert that it's the right thing. Also,
* if argsArg were strongly typed we'd still need casting below for this to
* compile, because typeArg is not known at compile-time here.
*/
template <typename Allocator>
bool init(Allocator* alloc, void* argsArg, uint16_t countArg,
ErrorArgumentsType typeArg, va_list ap) {
MOZ_ASSERT(countArg > 0);
count_ = countArg;
for (uint16_t i = 0; i < count_; i++) {
switch (typeArg) {
case ArgumentsAreASCII:
case ArgumentsAreUTF8: {
const char* c = argsArg ? static_cast<const char**>(argsArg)[i]
: va_arg(ap, const char*);
args_[i] = c;
MOZ_ASSERT_IF(typeArg == ArgumentsAreASCII,
JS::StringIsASCII(args_[i]));
lengths_[i] = strlen(args_[i]);
break;
}
case ArgumentsAreLatin1: {
MOZ_ASSERT(!argsArg);
const Latin1Char* latin1 = va_arg(ap, Latin1Char*);
size_t len = strlen(reinterpret_cast<const char*>(latin1));
mozilla::Range<const Latin1Char> range(latin1, len);
char* utf8 = JS::CharsToNewUTF8CharsZ(alloc, range).c_str();
if (!utf8) {
return false;
}
args_[i] = utf8;
lengths_[i] = strlen(utf8);
allocatedElements_ = true;
break;
}
case ArgumentsAreUnicode: {
const char16_t* uc = argsArg
? static_cast<const char16_t**>(argsArg)[i]
: va_arg(ap, const char16_t*);
size_t len = js_strlen(uc);
mozilla::Range<const char16_t> range(uc, len);
char* utf8 = JS::CharsToNewUTF8CharsZ(alloc, range).c_str();
if (!utf8) {
return false;
}
args_[i] = utf8;
lengths_[i] = strlen(utf8);
allocatedElements_ = true;
break;
}
}
totalLength_ += lengths_[i];
}
return true;
}
};
/*
* 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->message_.
*
* Returns true if the expansion succeeds (can fail if out of memory).
*
* messageArgs is a `const char**` or a `const char16_t**` but templating on
* that is not worth it here because AutoMessageArgs takes a void* anyway, and
* using void* here simplifies our callers a bit.
*/
template <typename T>
static bool ExpandErrorArgumentsHelper(FrontendContext* fc,
JSErrorCallback callback, void* userRef,
const unsigned errorNumber,
void* messageArgs,
ErrorArgumentsType argumentsType,
T* reportp, va_list ap) {
const JSErrorFormatString* efs;
if (!callback) {
callback = GetErrorMessage;
}
efs = fc->gcSafeCallback(callback, userRef, errorNumber);
if (efs) {
if constexpr (std::is_same_v<T, JSErrorReport>) {
reportp->exnType = efs->exnType;
}
MOZ_ASSERT(reportp->errorNumber == errorNumber);
reportp->errorMessageName = efs->name;
MOZ_ASSERT_IF(argumentsType == ArgumentsAreASCII,
JS::StringIsASCII(efs->format));
uint16_t argCount = efs->argCount;
MOZ_RELEASE_ASSERT(argCount <= JS::MaxNumErrorArguments);
if (argCount > 0) {
/*
* Parse the error format, substituting the argument X
* for {X} in the format.
*/
if (efs->format) {
const char* fmt;
char* out;
#ifdef DEBUG
int expandedArgs = 0;
#endif
size_t expandedLength;
size_t len = strlen(efs->format);
AutoMessageArgs args;
if (!args.init(fc->getAllocator(), messageArgs, argCount, argumentsType,
ap)) {
return false;
}
expandedLength = len - (3 * args.count()) /* exclude the {n} */
+ args.totalLength();
/*
* Note - the above calculation assumes that each argument
* is used once and only once in the expansion !!!
*/
char* utf8 = out =
fc->getAllocator()->pod_malloc<char>(expandedLength + 1);
if (!out) {
return false;
}
fmt = efs->format;
while (*fmt) {
if (*fmt == '{') {
if (mozilla::IsAsciiDigit(fmt[1])) {
int d = AsciiDigitToNumber(fmt[1]);
MOZ_RELEASE_ASSERT(d < args.count());
strncpy(out, args.args(d), args.lengths(d));
out += args.lengths(d);
fmt += 3;
#ifdef DEBUG
expandedArgs++;
#endif
continue;
}
}
*out++ = *fmt++;
}
MOZ_ASSERT(expandedArgs == args.count());
*out = 0;
reportp->initOwnedMessage(utf8);
}
} else {
/* Non-null messageArgs should have at least one non-null arg. */
MOZ_ASSERT(!messageArgs);
/*
* Zero arguments: the format string (if it exists) is the
* entire message.
*/
if (efs->format) {
reportp->initBorrowedMessage(efs->format);
}
}
}
if (!reportp->message()) {
/* where's the right place for this ??? */
const char* defaultErrorMessage =
"No error message available for error number %d";
size_t nbytes = strlen(defaultErrorMessage) + 16;
char* message = fc->getAllocator()->pod_malloc<char>(nbytes);
if (!message) {
return false;
}
snprintf(message, nbytes, defaultErrorMessage, errorNumber);
reportp->initOwnedMessage(message);
}
return true;
}
bool js::ExpandErrorArgumentsVA(FrontendContext* fc, JSErrorCallback callback,
void* userRef, const unsigned errorNumber,
const char16_t** messageArgs,
ErrorArgumentsType argumentsType,
JSErrorReport* reportp, va_list ap) {
MOZ_ASSERT(argumentsType == ArgumentsAreUnicode);
return ExpandErrorArgumentsHelper(fc, callback, userRef, errorNumber,
messageArgs, argumentsType, reportp, ap);
}
bool js::ExpandErrorArgumentsVA(FrontendContext* fc, JSErrorCallback callback,
void* userRef, const unsigned errorNumber,
const char** messageArgs,
ErrorArgumentsType argumentsType,
JSErrorReport* reportp, va_list ap) {
MOZ_ASSERT(argumentsType != ArgumentsAreUnicode);
return ExpandErrorArgumentsHelper(fc, callback, userRef, errorNumber,
messageArgs, argumentsType, reportp, ap);
}
bool js::ExpandErrorArgumentsVA(FrontendContext* fc, JSErrorCallback callback,
void* userRef, const unsigned errorNumber,
ErrorArgumentsType argumentsType,
JSErrorReport* reportp, va_list ap) {
return ExpandErrorArgumentsHelper(fc, callback, userRef, errorNumber, nullptr,
argumentsType, reportp, ap);
}
bool js::ExpandErrorArgumentsVA(FrontendContext* fc, JSErrorCallback callback,
void* userRef, const unsigned errorNumber,
const char16_t** messageArgs,
ErrorArgumentsType argumentsType,
JSErrorNotes::Note* notep, va_list ap) {
return ExpandErrorArgumentsHelper(fc, callback, userRef, errorNumber,
messageArgs, argumentsType, notep, ap);
}
bool js::ReportErrorNumberVA(JSContext* cx, IsWarning isWarning,
JSErrorCallback callback, void* userRef,
const unsigned errorNumber,
ErrorArgumentsType argumentsType, va_list ap) {
JSErrorReport report;
report.isWarning_ = isWarning == IsWarning::Yes;
report.errorNumber = errorNumber;
PopulateReportBlame(cx, &report);
AutoReportFrontendContext fc(cx);
if (!ExpandErrorArgumentsVA(&fc, callback, userRef, errorNumber,
argumentsType, &report, ap)) {
return false;
}
if (!ReportError(cx, &report, callback, userRef)) {
return false;
}
return report.isWarning();
}
template <typename CharT>
static bool ExpandErrorArguments(FrontendContext* fc, JSErrorCallback callback,
void* userRef, const unsigned errorNumber,
const CharT** messageArgs,
js::ErrorArgumentsType argumentsType,
JSErrorReport* reportp, ...) {
va_list ap;
va_start(ap, reportp);
bool expanded =
js::ExpandErrorArgumentsVA(fc, callback, userRef, errorNumber,
messageArgs, argumentsType, reportp, ap);
va_end(ap);
return expanded;
}
template <js::ErrorArgumentsType argType, typename CharT>
static bool ReportErrorNumberArray(JSContext* cx, IsWarning isWarning,
JSErrorCallback callback, void* userRef,
const unsigned errorNumber,
const CharT** args) {
static_assert(
(argType == ArgumentsAreUnicode && std::is_same_v<CharT, char16_t>) ||
(argType != ArgumentsAreUnicode && std::is_same_v<CharT, char>),
"Mismatch between character type and argument type");
JSErrorReport report;
report.isWarning_ = isWarning == IsWarning::Yes;
report.errorNumber = errorNumber;
PopulateReportBlame(cx, &report);
AutoReportFrontendContext fc(cx);
if (!ExpandErrorArguments(&fc, callback, userRef, errorNumber, args, argType,
&report)) {
return false;
}
if (!ReportError(cx, &report, callback, userRef)) {
return false;
}
return report.isWarning();
}
bool js::ReportErrorNumberUCArray(JSContext* cx, IsWarning isWarning,
JSErrorCallback callback, void* userRef,
const unsigned errorNumber,
const char16_t** args) {
return ReportErrorNumberArray<ArgumentsAreUnicode>(
cx, isWarning, callback, userRef, errorNumber, args);
}
bool js::ReportErrorNumberUTF8Array(JSContext* cx, IsWarning isWarning,
JSErrorCallback callback, void* userRef,
const unsigned errorNumber,
const char** args) {
return ReportErrorNumberArray<ArgumentsAreUTF8>(cx, isWarning, callback,
userRef, errorNumber, args);
}
bool js::ReportErrorVA(JSContext* cx, IsWarning isWarning, const char* format,
js::ErrorArgumentsType argumentsType, va_list ap) {
JSErrorReport report;
UniqueChars message(JS_vsmprintf(format, ap));
if (!message) {
ReportOutOfMemory(cx);
return false;
}
MOZ_ASSERT_IF(argumentsType == ArgumentsAreASCII,
JS::StringIsASCII(message.get()));
report.isWarning_ = isWarning == IsWarning::Yes;
report.errorNumber = JSMSG_USER_DEFINED_ERROR;
if (argumentsType == ArgumentsAreASCII || argumentsType == ArgumentsAreUTF8) {
report.initOwnedMessage(message.release());
} else {
MOZ_ASSERT(argumentsType == ArgumentsAreLatin1);
JS::Latin1Chars latin1(message.get(), strlen(message.get()));
JS::UTF8CharsZ utf8(JS::CharsToNewUTF8CharsZ(cx, latin1));
if (!utf8) {
return false;
}
report.initOwnedMessage(reinterpret_cast<const char*>(utf8.get()));
}
PopulateReportBlame(cx, &report);
if (!ReportError(cx, &report, nullptr, nullptr)) {
return false;
}
return report.isWarning();
}
void js::MaybePrintAndClearPendingException(JSContext* cx) {
if (!cx->isExceptionPending()) {
return;
}
AutoClearPendingException acpe(cx);
JS::ExceptionStack exnStack(cx);
if (!JS::StealPendingExceptionStack(cx, &exnStack)) {
fprintf(stderr, "error getting pending exception\n");
return;
}
JS::ErrorReportBuilder report(cx);
if (!report.init(cx, exnStack, JS::ErrorReportBuilder::WithSideEffects)) {
fprintf(stderr, "out of memory initializing JS::ErrorReportBuilder\n");
return;
}
MOZ_ASSERT(!report.report()->isWarning());
JS::PrintError(stderr, report, true);
}