dart-sdk/runtime/vm/json_stream.cc
John McCutchan 904beb3d9d Avoid many temporary allocations when serializing service protocol responses
- [x] Use an on stack buffer for small string allocations.
- [x] Avoid unnecessary calls to strlen.

Related #29207

BUG=
R=rmacnak@google.com, zra@google.com

Review-Url: https://codereview.chromium.org/2791633002 .
2017-03-31 13:20:11 -07:00

1050 lines
27 KiB
C++

// Copyright (c) 2013, the Dart project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.
#include "platform/assert.h"
#include "include/dart_native_api.h"
#include "vm/dart_entry.h"
#include "vm/debugger.h"
#include "vm/json_stream.h"
#include "vm/message.h"
#include "vm/metrics.h"
#include "vm/object.h"
#include "vm/safepoint.h"
#include "vm/service.h"
#include "vm/service_event.h"
#include "vm/thread_registry.h"
#include "vm/timeline.h"
#include "vm/unicode.h"
namespace dart {
#ifndef PRODUCT
class MaybeOnStackBuffer {
public:
explicit MaybeOnStackBuffer(intptr_t size) {
if (size > kOnStackBufferCapacity) {
p_ = reinterpret_cast<char*>(malloc(size));
} else {
p_ = &buffer_[0];
}
}
~MaybeOnStackBuffer() {
if (p_ != &buffer_[0]) free(p_);
}
char* p() { return p_; }
private:
static const intptr_t kOnStackBufferCapacity = 4096;
char* p_;
char buffer_[kOnStackBufferCapacity];
};
void AppendJSONStreamConsumer(Dart_StreamConsumer_State state,
const char* stream_name,
const uint8_t* buffer,
intptr_t buffer_length,
void* user_data) {
if ((state == Dart_StreamConsumer_kStart) ||
(state == Dart_StreamConsumer_kFinish)) {
// Ignore.
return;
}
ASSERT(state == Dart_StreamConsumer_kData);
JSONStream* js = reinterpret_cast<JSONStream*>(user_data);
ASSERT(js != NULL);
js->AppendSerializedObject(buffer, buffer_length);
}
DECLARE_FLAG(bool, trace_service);
JSONStream::JSONStream(intptr_t buf_size)
: open_objects_(0),
buffer_(buf_size),
default_id_zone_(),
id_zone_(&default_id_zone_),
reply_port_(ILLEGAL_PORT),
seq_(NULL),
parameter_keys_(NULL),
parameter_values_(NULL),
method_(""),
param_keys_(NULL),
param_values_(NULL),
num_params_(0),
offset_(0),
count_(-1) {
ObjectIdRing* ring = NULL;
Isolate* isolate = Isolate::Current();
if (isolate != NULL) {
ring = isolate->object_id_ring();
}
default_id_zone_.Init(ring, ObjectIdRing::kAllocateId);
}
JSONStream::~JSONStream() {}
void JSONStream::Setup(Zone* zone,
Dart_Port reply_port,
const Instance& seq,
const String& method,
const Array& param_keys,
const Array& param_values,
bool parameters_are_dart_objects) {
set_reply_port(reply_port);
seq_ = &Instance::ZoneHandle(seq.raw());
method_ = method.ToCString();
if (parameters_are_dart_objects) {
parameter_keys_ = &Array::ZoneHandle(param_keys.raw());
parameter_values_ = &Array::ZoneHandle(param_values.raw());
ASSERT(parameter_keys_->Length() == parameter_values_->Length());
} else if (param_keys.Length() > 0) {
String& string_iterator = String::Handle();
ASSERT(param_keys.Length() == param_values.Length());
const char** param_keys_native =
zone->Alloc<const char*>(param_keys.Length());
const char** param_values_native =
zone->Alloc<const char*>(param_keys.Length());
for (intptr_t i = 0; i < param_keys.Length(); i++) {
string_iterator ^= param_keys.At(i);
param_keys_native[i] =
zone->MakeCopyOfString(string_iterator.ToCString());
string_iterator ^= param_values.At(i);
param_values_native[i] =
zone->MakeCopyOfString(string_iterator.ToCString());
}
SetParams(param_keys_native, param_values_native, param_keys.Length());
}
if (FLAG_trace_service) {
Isolate* isolate = Isolate::Current();
ASSERT(isolate != NULL);
const char* isolate_name = isolate->name();
setup_time_micros_ = OS::GetCurrentTimeMicros();
OS::Print("[+%" Pd64 "ms] Isolate %s processing service request %s\n",
Dart::UptimeMillis(), isolate_name, method_);
}
buffer_.Printf("{\"jsonrpc\":\"2.0\", \"result\":");
}
void JSONStream::SetupError() {
buffer_.Clear();
buffer_.Printf("{\"jsonrpc\":\"2.0\", \"error\":");
}
static const char* GetJSONRpcErrorMessage(intptr_t code) {
switch (code) {
case kParseError:
return "Parse error";
case kInvalidRequest:
return "Invalid Request";
case kMethodNotFound:
return "Method not found";
case kInvalidParams:
return "Invalid params";
case kInternalError:
return "Internal error";
case kFeatureDisabled:
return "Feature is disabled";
case kCannotAddBreakpoint:
return "Cannot add breakpoint";
case kIsolateMustBeRunnable:
return "Isolate must be runnable";
case kIsolateMustBePaused:
return "Isolate must be paused";
case kCannotResume:
return "Cannot resume execution";
case kIsolateIsReloading:
return "Isolate is reloading";
case kFileSystemAlreadyExists:
return "File system already exists";
case kFileSystemDoesNotExist:
return "File system does not exist";
case kFileDoesNotExist:
return "File does not exist";
case kIsolateReloadBarred:
return "Isolate cannot be reloaded";
default:
return "Extension error";
}
}
static void PrintRequest(JSONObject* obj, JSONStream* js) {
JSONObject jsobj(obj, "request");
jsobj.AddProperty("method", js->method());
{
JSONObject params(&jsobj, "params");
for (intptr_t i = 0; i < js->num_params(); i++) {
params.AddProperty(js->GetParamKey(i), js->GetParamValue(i));
}
}
}
void JSONStream::PrintError(intptr_t code, const char* details_format, ...) {
SetupError();
JSONObject jsobj(this);
jsobj.AddProperty("code", code);
jsobj.AddProperty("message", GetJSONRpcErrorMessage(code));
{
JSONObject data(&jsobj, "data");
PrintRequest(&data, this);
if (details_format != NULL) {
va_list args;
va_start(args, details_format);
intptr_t len = OS::VSNPrint(NULL, 0, details_format, args);
va_end(args);
char* buffer = Thread::Current()->zone()->Alloc<char>(len + 1);
va_list args2;
va_start(args2, details_format);
OS::VSNPrint(buffer, (len + 1), details_format, args2);
va_end(args2);
data.AddProperty("details", buffer);
}
}
}
void JSONStream::PostNullReply(Dart_Port port) {
PortMap::PostMessage(
new Message(port, Object::null(), Message::kNormalPriority));
}
static void Finalizer(void* isolate_callback_data,
Dart_WeakPersistentHandle handle,
void* buffer) {
free(buffer);
}
void JSONStream::PostReply() {
ASSERT(seq_ != NULL);
Dart_Port port = reply_port();
set_reply_port(ILLEGAL_PORT); // Prevent double replies.
if (seq_->IsString()) {
const String& str = String::Cast(*seq_);
PrintProperty("id", str.ToCString());
} else if (seq_->IsInteger()) {
const Integer& integer = Integer::Cast(*seq_);
PrintProperty64("id", integer.AsInt64Value());
} else if (seq_->IsDouble()) {
const Double& dbl = Double::Cast(*seq_);
PrintProperty("id", dbl.value());
} else if (seq_->IsNull()) {
if (port == ILLEGAL_PORT) {
// This path is only used in tests.
buffer_.AddChar('}'); // Finish our message.
char* cstr;
intptr_t length;
Steal(&cstr, &length);
OS::PrintErr("-----\nDropping reply:\n%s\n-----\n", cstr);
free(cstr);
}
// JSON-RPC 2.0 says that a request with a null ID shouldn't get a reply.
PostNullReply(port);
return;
}
ASSERT(port != ILLEGAL_PORT);
buffer_.AddChar('}'); // Finish our message.
char* cstr;
intptr_t length;
Steal(&cstr, &length);
bool result;
{
TransitionVMToNative transition(Thread::Current());
Dart_CObject bytes;
bytes.type = Dart_CObject_kExternalTypedData;
bytes.value.as_external_typed_data.type = Dart_TypedData_kUint8;
bytes.value.as_external_typed_data.length = length;
bytes.value.as_external_typed_data.data = reinterpret_cast<uint8_t*>(cstr);
bytes.value.as_external_typed_data.peer = cstr;
bytes.value.as_external_typed_data.callback = Finalizer;
Dart_CObject* elements[1];
elements[0] = &bytes;
Dart_CObject message;
message.type = Dart_CObject_kArray;
message.value.as_array.length = 1;
message.value.as_array.values = elements;
result = Dart_PostCObject(port, &message);
}
if (!result) {
free(cstr);
}
if (FLAG_trace_service) {
Isolate* isolate = Isolate::Current();
ASSERT(isolate != NULL);
const char* isolate_name = isolate->name();
int64_t total_time = OS::GetCurrentTimeMicros() - setup_time_micros_;
if (result) {
OS::Print("[+%" Pd64
"ms] Isolate %s processed service request %s "
"(%" Pd64 "us)\n",
Dart::UptimeMillis(), isolate_name, method_, total_time);
} else {
OS::Print("[+%" Pd64
"ms] Isolate %s processed service request %s "
"(%" Pd64 "us) FAILED\n",
Dart::UptimeMillis(), isolate_name, method_, total_time);
}
}
}
const char* JSONStream::LookupParam(const char* key) const {
for (int i = 0; i < num_params(); i++) {
if (!strcmp(key, param_keys_[i])) {
return param_values_[i];
}
}
return NULL;
}
bool JSONStream::HasParam(const char* key) const {
ASSERT(key);
return LookupParam(key) != NULL;
}
bool JSONStream::ParamIs(const char* key, const char* value) const {
ASSERT(key);
ASSERT(value);
const char* key_value = LookupParam(key);
return (key_value != NULL) && (strcmp(key_value, value) == 0);
}
void JSONStream::ComputeOffsetAndCount(intptr_t length,
intptr_t* offset,
intptr_t* count) {
// This function is written to avoid adding (count + offset) in case
// that triggers an integer overflow.
*offset = offset_;
if (*offset > length) {
*offset = length;
}
intptr_t remaining = length - *offset;
*count = count_;
if (*count < 0 || *count > remaining) {
*count = remaining;
}
}
void JSONStream::AppendSerializedObject(const char* serialized_object) {
PrintCommaIfNeeded();
buffer_.AddString(serialized_object);
}
void JSONStream::AppendSerializedObject(const uint8_t* buffer,
intptr_t buffer_length) {
buffer_.AddRaw(buffer, buffer_length);
}
void JSONStream::AppendSerializedObject(const char* property_name,
const char* serialized_object) {
PrintCommaIfNeeded();
PrintPropertyName(property_name);
buffer_.AddString(serialized_object);
}
void JSONStream::Clear() {
buffer_.Clear();
open_objects_ = 0;
}
void JSONStream::OpenObject(const char* property_name) {
PrintCommaIfNeeded();
open_objects_++;
if (property_name != NULL) {
PrintPropertyName(property_name);
}
buffer_.AddChar('{');
}
void JSONStream::CloseObject() {
ASSERT(open_objects_ > 0);
open_objects_--;
buffer_.AddChar('}');
}
void JSONStream::OpenArray(const char* property_name) {
PrintCommaIfNeeded();
if (property_name != NULL) {
PrintPropertyName(property_name);
}
open_objects_++;
buffer_.AddChar('[');
}
void JSONStream::CloseArray() {
ASSERT(open_objects_ > 0);
open_objects_--;
buffer_.AddChar(']');
}
void JSONStream::PrintValueNull() {
PrintCommaIfNeeded();
buffer_.Printf("null");
}
void JSONStream::PrintValueBool(bool b) {
PrintCommaIfNeeded();
buffer_.Printf("%s", b ? "true" : "false");
}
void JSONStream::PrintValue(intptr_t i) {
EnsureIntegerIsRepresentableInJavaScript(static_cast<int64_t>(i));
PrintCommaIfNeeded();
buffer_.Printf("%" Pd "", i);
}
void JSONStream::PrintValue64(int64_t i) {
EnsureIntegerIsRepresentableInJavaScript(i);
PrintCommaIfNeeded();
buffer_.Printf("%" Pd64 "", i);
}
void JSONStream::PrintValueTimeMillis(int64_t millis) {
EnsureIntegerIsRepresentableInJavaScript(millis);
PrintValue64(millis);
}
void JSONStream::PrintValueTimeMicros(int64_t micros) {
EnsureIntegerIsRepresentableInJavaScript(micros);
PrintValue64(micros);
}
void JSONStream::PrintValue(double d) {
PrintCommaIfNeeded();
buffer_.Printf("%f", d);
}
static const char base64_digits[65] =
"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
static const char base64_pad = '=';
void JSONStream::PrintValueBase64(const uint8_t* bytes, intptr_t length) {
PrintCommaIfNeeded();
buffer_.AddChar('"');
intptr_t odd_bits = length % 3;
intptr_t even_bits = length - odd_bits;
for (intptr_t i = 0; i < even_bits; i += 3) {
intptr_t triplet = (bytes[i] << 16) | (bytes[i + 1] << 8) | bytes[i + 2];
buffer_.AddChar(base64_digits[triplet >> 18]);
buffer_.AddChar(base64_digits[(triplet >> 12) & 63]);
buffer_.AddChar(base64_digits[(triplet >> 6) & 63]);
buffer_.AddChar(base64_digits[triplet & 63]);
}
if (odd_bits == 1) {
intptr_t triplet = bytes[even_bits] << 16;
buffer_.AddChar(base64_digits[triplet >> 18]);
buffer_.AddChar(base64_digits[(triplet >> 12) & 63]);
buffer_.AddChar(base64_pad);
buffer_.AddChar(base64_pad);
} else if (odd_bits == 2) {
intptr_t triplet = (bytes[even_bits] << 16) | (bytes[even_bits + 1] << 8);
buffer_.AddChar(base64_digits[triplet >> 18]);
buffer_.AddChar(base64_digits[(triplet >> 12) & 63]);
buffer_.AddChar(base64_digits[(triplet >> 6) & 63]);
buffer_.AddChar(base64_pad);
}
buffer_.AddChar('"');
}
void JSONStream::PrintValue(const char* s) {
PrintCommaIfNeeded();
buffer_.AddChar('"');
AddEscapedUTF8String(s);
buffer_.AddChar('"');
}
bool JSONStream::PrintValueStr(const String& s,
intptr_t offset,
intptr_t count) {
PrintCommaIfNeeded();
buffer_.AddChar('"');
bool did_truncate = AddDartString(s, offset, count);
buffer_.AddChar('"');
return did_truncate;
}
void JSONStream::PrintValueNoEscape(const char* s) {
PrintCommaIfNeeded();
buffer_.Printf("%s", s);
}
void JSONStream::PrintfValue(const char* format, ...) {
PrintCommaIfNeeded();
va_list args;
va_start(args, format);
intptr_t len = OS::VSNPrint(NULL, 0, format, args);
va_end(args);
MaybeOnStackBuffer mosb(len + 1);
char* p = mosb.p();
va_start(args, format);
intptr_t len2 = OS::VSNPrint(p, len + 1, format, args);
va_end(args);
ASSERT(len == len2);
buffer_.AddChar('"');
AddEscapedUTF8String(p, len);
buffer_.AddChar('"');
}
void JSONStream::PrintValue(const Object& o, bool ref) {
PrintCommaIfNeeded();
o.PrintJSON(this, ref);
}
void JSONStream::PrintValue(Breakpoint* bpt) {
PrintCommaIfNeeded();
bpt->PrintJSON(this);
}
void JSONStream::PrintValue(TokenPosition tp) {
PrintCommaIfNeeded();
PrintValue(tp.value());
}
void JSONStream::PrintValue(const ServiceEvent* event) {
PrintCommaIfNeeded();
event->PrintJSON(this);
}
void JSONStream::PrintValue(Metric* metric) {
PrintCommaIfNeeded();
metric->PrintJSON(this);
}
void JSONStream::PrintValue(MessageQueue* queue) {
PrintCommaIfNeeded();
queue->PrintJSON(this);
}
void JSONStream::PrintValue(Isolate* isolate, bool ref) {
PrintCommaIfNeeded();
isolate->PrintJSON(this, ref);
}
void JSONStream::PrintValue(ThreadRegistry* reg) {
PrintCommaIfNeeded();
reg->PrintJSON(this);
}
void JSONStream::PrintValue(Thread* thread) {
PrintCommaIfNeeded();
thread->PrintJSON(this);
}
void JSONStream::PrintValue(const TimelineEvent* timeline_event) {
PrintCommaIfNeeded();
timeline_event->PrintJSON(this);
}
void JSONStream::PrintValue(const TimelineEventBlock* timeline_event_block) {
PrintCommaIfNeeded();
timeline_event_block->PrintJSON(this);
}
void JSONStream::PrintValueVM(bool ref) {
PrintCommaIfNeeded();
Service::PrintJSONForVM(this, ref);
}
void JSONStream::PrintServiceId(const Object& o) {
ASSERT(id_zone_ != NULL);
PrintProperty("id", id_zone_->GetServiceId(o));
}
void JSONStream::PrintPropertyBool(const char* name, bool b) {
PrintPropertyName(name);
PrintValueBool(b);
}
void JSONStream::PrintProperty(const char* name, intptr_t i) {
PrintPropertyName(name);
PrintValue(i);
}
void JSONStream::PrintProperty64(const char* name, int64_t i) {
PrintPropertyName(name);
PrintValue64(i);
}
void JSONStream::PrintPropertyTimeMillis(const char* name, int64_t millis) {
PrintProperty64(name, millis);
}
void JSONStream::PrintPropertyTimeMicros(const char* name, int64_t micros) {
PrintProperty64(name, micros);
}
void JSONStream::PrintProperty(const char* name, double d) {
PrintPropertyName(name);
PrintValue(d);
}
void JSONStream::PrintProperty(const char* name, const char* s) {
PrintPropertyName(name);
PrintValue(s);
}
void JSONStream::PrintPropertyBase64(const char* name,
const uint8_t* b,
intptr_t len) {
PrintPropertyName(name);
PrintValueBase64(b, len);
}
bool JSONStream::PrintPropertyStr(const char* name,
const String& s,
intptr_t offset,
intptr_t count) {
PrintPropertyName(name);
return PrintValueStr(s, offset, count);
}
void JSONStream::PrintPropertyNoEscape(const char* name, const char* s) {
PrintPropertyName(name);
PrintValueNoEscape(s);
}
void JSONStream::PrintProperty(const char* name, const ServiceEvent* event) {
PrintPropertyName(name);
PrintValue(event);
}
void JSONStream::PrintProperty(const char* name, Breakpoint* bpt) {
PrintPropertyName(name);
PrintValue(bpt);
}
void JSONStream::PrintProperty(const char* name, TokenPosition tp) {
PrintPropertyName(name);
PrintValue(tp);
}
void JSONStream::PrintProperty(const char* name, Metric* metric) {
PrintPropertyName(name);
PrintValue(metric);
}
void JSONStream::PrintProperty(const char* name, MessageQueue* queue) {
PrintPropertyName(name);
PrintValue(queue);
}
void JSONStream::PrintProperty(const char* name, Isolate* isolate) {
PrintPropertyName(name);
PrintValue(isolate);
}
void JSONStream::PrintProperty(const char* name, ThreadRegistry* reg) {
PrintPropertyName(name);
PrintValue(reg);
}
void JSONStream::PrintProperty(const char* name, Thread* thread) {
PrintPropertyName(name);
PrintValue(thread);
}
void JSONStream::PrintProperty(const char* name,
const TimelineEvent* timeline_event) {
PrintPropertyName(name);
PrintValue(timeline_event);
}
void JSONStream::PrintProperty(const char* name,
const TimelineEventBlock* timeline_event_block) {
PrintPropertyName(name);
PrintValue(timeline_event_block);
}
void JSONStream::PrintfProperty(const char* name, const char* format, ...) {
PrintPropertyName(name);
va_list args;
va_start(args, format);
intptr_t len = OS::VSNPrint(NULL, 0, format, args);
va_end(args);
MaybeOnStackBuffer mosb(len + 1);
char* p = mosb.p();
va_start(args, format);
intptr_t len2 = OS::VSNPrint(p, len + 1, format, args);
va_end(args);
ASSERT(len == len2);
buffer_.AddChar('"');
AddEscapedUTF8String(p, len);
buffer_.AddChar('"');
}
void JSONStream::Steal(char** buffer, intptr_t* buffer_length) {
ASSERT(buffer != NULL);
ASSERT(buffer_length != NULL);
*buffer_length = buffer_.length();
*buffer = buffer_.Steal();
}
void JSONStream::set_reply_port(Dart_Port port) {
reply_port_ = port;
}
intptr_t JSONStream::NumObjectParameters() const {
if (parameter_keys_ == NULL) {
return 0;
}
ASSERT(parameter_keys_ != NULL);
ASSERT(parameter_values_ != NULL);
return parameter_keys_->Length();
}
RawObject* JSONStream::GetObjectParameterKey(intptr_t i) const {
ASSERT((i >= 0) && (i < NumObjectParameters()));
return parameter_keys_->At(i);
}
RawObject* JSONStream::GetObjectParameterValue(intptr_t i) const {
ASSERT((i >= 0) && (i < NumObjectParameters()));
return parameter_values_->At(i);
}
RawObject* JSONStream::LookupObjectParam(const char* c_key) const {
const String& key = String::Handle(String::New(c_key));
Object& test = Object::Handle();
const intptr_t num_object_parameters = NumObjectParameters();
for (intptr_t i = 0; i < num_object_parameters; i++) {
test = GetObjectParameterKey(i);
if (test.IsString() && String::Cast(test).Equals(key)) {
return GetObjectParameterValue(i);
}
}
return Object::null();
}
void JSONStream::SetParams(const char** param_keys,
const char** param_values,
intptr_t num_params) {
param_keys_ = param_keys;
param_values_ = param_values;
num_params_ = num_params;
}
void JSONStream::PrintProperty(const char* name, const Object& o, bool ref) {
PrintPropertyName(name);
PrintValue(o, ref);
}
void JSONStream::PrintPropertyVM(const char* name, bool ref) {
PrintPropertyName(name);
PrintValueVM(ref);
}
void JSONStream::PrintPropertyName(const char* name) {
ASSERT(name != NULL);
PrintCommaIfNeeded();
buffer_.AddChar('"');
AddEscapedUTF8String(name);
buffer_.AddChar('"');
buffer_.AddChar(':');
}
void JSONStream::PrintCommaIfNeeded() {
if (NeedComma()) {
buffer_.AddChar(',');
}
}
bool JSONStream::NeedComma() {
const char* buffer = buffer_.buf();
intptr_t length = buffer_.length();
if (length == 0) {
return false;
}
char ch = buffer[length - 1];
return (ch != '[') && (ch != '{') && (ch != ':') && (ch != ',');
}
void JSONStream::EnsureIntegerIsRepresentableInJavaScript(int64_t i) {
#ifdef DEBUG
if (!Utils::IsJavascriptInt(i)) {
OS::Print(
"JSONStream::EnsureIntegerIsRepresentableInJavaScript failed on "
"%" Pd64 "\n",
i);
UNREACHABLE();
}
#endif
}
void JSONStream::AddEscapedUTF8String(const char* s) {
if (s == NULL) {
return;
}
intptr_t len = strlen(s);
AddEscapedUTF8String(s, len);
}
void JSONStream::AddEscapedUTF8String(const char* s, intptr_t len) {
if (s == NULL) {
return;
}
const uint8_t* s8 = reinterpret_cast<const uint8_t*>(s);
intptr_t i = 0;
for (; i < len;) {
// Extract next UTF8 character.
int32_t ch = 0;
int32_t ch_len = Utf8::Decode(&s8[i], len - i, &ch);
ASSERT(ch_len != 0);
buffer_.EscapeAndAddCodeUnit(ch);
// Move i forward.
i += ch_len;
}
ASSERT(i == len);
}
bool JSONStream::AddDartString(const String& s,
intptr_t offset,
intptr_t count) {
intptr_t length = s.Length();
ASSERT(offset >= 0);
if (offset > length) {
offset = length;
}
if (!Utils::RangeCheck(offset, count, length)) {
count = length - offset;
}
intptr_t limit = offset + count;
for (intptr_t i = offset; i < limit; i++) {
uint16_t code_unit = s.CharAt(i);
if (Utf16::IsTrailSurrogate(code_unit)) {
buffer_.EscapeAndAddUTF16CodeUnit(code_unit);
} else if (Utf16::IsLeadSurrogate(code_unit)) {
if (i + 1 == limit) {
buffer_.EscapeAndAddUTF16CodeUnit(code_unit);
} else {
uint16_t next_code_unit = s.CharAt(i + 1);
if (Utf16::IsTrailSurrogate(next_code_unit)) {
uint32_t decoded = Utf16::Decode(code_unit, next_code_unit);
buffer_.EscapeAndAddCodeUnit(decoded);
i++;
} else {
buffer_.EscapeAndAddUTF16CodeUnit(code_unit);
}
}
} else {
buffer_.EscapeAndAddCodeUnit(code_unit);
}
}
// Return value indicates whether the string is truncated.
return (offset > 0) || (limit < length);
}
JSONObject::JSONObject(const JSONArray* arr) : stream_(arr->stream_) {
stream_->OpenObject();
}
void JSONObject::AddFixedServiceId(const char* format, ...) const {
// Mark that this id is fixed.
AddProperty("fixedId", true);
// Add the id property.
stream_->PrintPropertyName("id");
va_list args;
va_start(args, format);
intptr_t len = OS::VSNPrint(NULL, 0, format, args);
va_end(args);
MaybeOnStackBuffer mosb(len + 1);
char* p = mosb.p();
va_start(args, format);
intptr_t len2 = OS::VSNPrint(p, len + 1, format, args);
va_end(args);
ASSERT(len == len2);
stream_->buffer_.AddChar('"');
stream_->AddEscapedUTF8String(p, len);
stream_->buffer_.AddChar('"');
}
void JSONObject::AddLocation(const Script& script,
TokenPosition token_pos,
TokenPosition end_token_pos) const {
JSONObject location(this, "location");
location.AddProperty("type", "SourceLocation");
location.AddProperty("script", script);
location.AddProperty("tokenPos", token_pos);
if (end_token_pos.IsReal()) {
location.AddProperty("endTokenPos", end_token_pos);
}
}
void JSONObject::AddLocation(const BreakpointLocation* bpt_loc) const {
ASSERT(bpt_loc->IsResolved());
Zone* zone = Thread::Current()->zone();
Library& library = Library::Handle(zone);
Script& script = Script::Handle(zone);
TokenPosition token_pos = TokenPosition::kNoSource;
bpt_loc->GetCodeLocation(&library, &script, &token_pos);
AddLocation(script, token_pos);
}
void JSONObject::AddUnresolvedLocation(
const BreakpointLocation* bpt_loc) const {
ASSERT(!bpt_loc->IsResolved());
Zone* zone = Thread::Current()->zone();
Library& library = Library::Handle(zone);
Script& script = Script::Handle(zone);
TokenPosition token_pos = TokenPosition::kNoSource;
bpt_loc->GetCodeLocation(&library, &script, &token_pos);
JSONObject location(this, "location");
location.AddProperty("type", "UnresolvedSourceLocation");
if (!script.IsNull()) {
location.AddProperty("script", script);
} else {
const String& scriptUri = String::Handle(zone, bpt_loc->url());
location.AddPropertyStr("scriptUri", scriptUri);
}
if (bpt_loc->requested_line_number() >= 0) {
// This unresolved breakpoint was specified at a particular line.
location.AddProperty("line", bpt_loc->requested_line_number());
if (bpt_loc->requested_column_number() >= 0) {
location.AddProperty("column", bpt_loc->requested_column_number());
}
} else {
// This unresolved breakpoint was requested at some function entry.
location.AddProperty("tokenPos", token_pos);
}
}
void JSONObject::AddPropertyF(const char* name, const char* format, ...) const {
stream_->PrintPropertyName(name);
va_list args;
va_start(args, format);
intptr_t len = OS::VSNPrint(NULL, 0, format, args);
va_end(args);
MaybeOnStackBuffer mosb(len + 1);
char* p = mosb.p();
va_start(args, format);
intptr_t len2 = OS::VSNPrint(p, len + 1, format, args);
va_end(args);
ASSERT(len == len2);
stream_->buffer_.AddChar('"');
stream_->AddEscapedUTF8String(p, len);
stream_->buffer_.AddChar('"');
}
void JSONArray::AddValueF(const char* format, ...) const {
stream_->PrintCommaIfNeeded();
va_list args;
va_start(args, format);
intptr_t len = OS::VSNPrint(NULL, 0, format, args);
va_end(args);
MaybeOnStackBuffer mosb(len + 1);
char* p = mosb.p();
va_start(args, format);
intptr_t len2 = OS::VSNPrint(p, len + 1, format, args);
va_end(args);
ASSERT(len == len2);
stream_->buffer_.AddChar('"');
stream_->AddEscapedUTF8String(p, len);
stream_->buffer_.AddChar('"');
}
#endif // !PRODUCT
} // namespace dart