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/*
* Copyright (C) 2015 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "JSONObject.h"
#include <ctype.h>
#include <math.h>
#include <media/stagefright/foundation/ADebug.h>
#include <media/stagefright/foundation/AString.h>
#include <media/stagefright/MediaErrors.h>
namespace android {
// Returns ERROR_MALFORMED if the value overflows a signed int, returns
// 0 otherwise.
// This method will assert if it is asked to parse a character which is not
// a digit.
static ssize_t parseInt32(const char *data, size_t numDigits, int32_t *out) {
int32_t x = 0;
for (size_t i = 0; i < numDigits; ++i) {
int32_t old_x = x;
x *= 10;
x += data[i] - '0';
CHECK(isdigit(data[i]));
if (x < old_x) {
// We've overflowed.
return ERROR_MALFORMED;
}
}
*out = x;
return 0;
}
// static
ssize_t JSONValue::Parse(const char *data, size_t size, JSONValue *out) {
size_t offset = 0;
while (offset < size && isspace(data[offset])) {
++offset;
}
if (offset == size) {
return ERROR_MALFORMED;
}
if (data[offset] == '[') {
sp<JSONArray> array = new JSONArray;
++offset;
for (;;) {
while (offset < size && isspace(data[offset])) {
++offset;
}
if (offset == size) {
return ERROR_MALFORMED;
}
if (data[offset] == ']') {
++offset;
break;
}
JSONValue val;
ssize_t n = Parse(&data[offset], size - offset, &val);
if (n < 0) {
return n;
}
array->addValue(val);
offset += n;
while (offset < size && isspace(data[offset])) {
++offset;
}
if (offset == size) {
return ERROR_MALFORMED;
}
if (data[offset] == ',') {
++offset;
} else if (data[offset] != ']') {
return ERROR_MALFORMED;
}
};
out->setArray(array);
return offset;
} else if (data[offset] == '{') {
sp<JSONObject> obj = new JSONObject;
++offset;
for (;;) {
while (offset < size && isspace(data[offset])) {
++offset;
}
if (offset == size) {
return ERROR_MALFORMED;
}
if (data[offset] == '}') {
++offset;
break;
}
JSONValue key;
ssize_t n = Parse(&data[offset], size - offset, &key);
if (n < 0) {
return n;
}
if (key.type() != TYPE_STRING) {
return ERROR_MALFORMED;
}
offset += n;
while (offset < size && isspace(data[offset])) {
++offset;
}
if (offset == size || data[offset] != ':') {
return ERROR_MALFORMED;
}
++offset;
JSONValue val;
n = Parse(&data[offset], size - offset, &val);
if (n < 0) {
return n;
}
AString keyVal;
CHECK(key.getString(&keyVal));
obj->setValue(keyVal.c_str(), val);
offset += n;
while (offset < size && isspace(data[offset])) {
++offset;
}
if (offset == size) {
return ERROR_MALFORMED;
}
if (data[offset] == ',') {
++offset;
} else if (data[offset] != '}') {
return ERROR_MALFORMED;
}
};
out->setObject(obj);
return offset;
} else if (data[offset] == '"') {
++offset;
AString s;
bool escaped = false;
while (offset < size) {
if (escaped) {
char c;
switch (data[offset]) {
case '\"':
case '\\':
case '/':
c = data[offset];
break;
case 'b':
c = '\x08';
break;
case 'f':
c = '\x0c';
break;
case 'n':
c = '\x0a';
break;
case 'r':
c = '\x0d';
break;
case 't':
c = '\x09';
break;
default:
return ERROR_MALFORMED;
}
s.append(c);
++offset;
escaped = false;
} else if (data[offset] == '\\') {
escaped = true;
} else if (data[offset] == '"') {
break;
}
s.append(data[offset++]);
}
if (offset == size) {
return ERROR_MALFORMED;
}
++offset;
out->setString(s);
return offset;
} else if (isdigit(data[offset]) || data[offset] == '-') {
bool negate = false;
if (data[offset] == '-') {
negate = true;
++offset;
if (offset == size) {
return ERROR_MALFORMED;
}
}
size_t firstDigitOffset = offset;
while (offset < size && isdigit(data[offset])) {
++offset;
}
size_t numDigits = offset - firstDigitOffset;
if (numDigits > 1 && data[firstDigitOffset] == '0') {
// No leading zeros.
return ERROR_MALFORMED;
}
size_t firstFracDigitOffset = 0;
size_t numFracDigits = 0;
if (offset < size && data[offset] == '.') {
++offset;
firstFracDigitOffset = offset;
while (offset < size && isdigit(data[offset])) {
++offset;
}
numFracDigits = offset - firstFracDigitOffset;
if (numFracDigits == 0) {
return ERROR_MALFORMED;
}
}
bool negateExponent = false;
size_t firstExpDigitOffset = 0;
size_t numExpDigits = 0;
if (offset < size && (data[offset] == 'e' || data[offset] == 'E')) {
++offset;
if (offset == size) {
return ERROR_MALFORMED;
}
if (data[offset] == '+' || data[offset] == '-') {
if (data[offset] == '-') {
negateExponent = true;
}
++offset;
}
firstExpDigitOffset = offset;
while (offset < size && isdigit(data[offset])) {
++offset;
}
numExpDigits = offset - firstExpDigitOffset;
if (numExpDigits == 0) {
return ERROR_MALFORMED;
}
}
if (numFracDigits == 0 && numExpDigits == 0) {
int32_t x;
if (parseInt32(&data[firstDigitOffset], numDigits, &x) != 0) {
return ERROR_MALFORMED;
}
out->setInt32(negate ? -x : x);
} else {
int32_t mantissa;
if (parseInt32(&data[firstDigitOffset], numDigits, &mantissa) != 0) {
return ERROR_MALFORMED;
}
int32_t fraction;
if (parseInt32(&data[firstFracDigitOffset], numFracDigits, &fraction) != 0) {
return ERROR_MALFORMED;
}
int32_t exponent;
if (parseInt32(&data[firstExpDigitOffset], numExpDigits, &exponent) != 0) {
return ERROR_MALFORMED;
}
if (negateExponent) {
exponent = -exponent;
}
float x = (float)mantissa;
x += (float)fraction * powf(10.0f, exponent - (int32_t)numFracDigits);
out->setFloat(negate ? -x : x);
}
return offset;
} else if (offset + 4 <= size && !strncmp("null", &data[offset], 4)) {
out->unset();
return offset + 4;
} else if (offset + 4 <= size && !strncmp("true", &data[offset], 4)) {
out->setBoolean(true);
return offset + 4;
} else if (offset + 5 <= size && !strncmp("false", &data[offset], 5)) {
out->setBoolean(false);
return offset + 5;
}
return ERROR_MALFORMED;
}
JSONValue::JSONValue()
: mType(TYPE_NULL) {
}
JSONValue::JSONValue(const JSONValue &other)
: mType(TYPE_NULL) {
*this = other;
}
JSONValue &JSONValue::operator=(const JSONValue &other) {
if (&other != this) {
unset();
mType = other.mType;
mValue = other.mValue;
switch (mType) {
case TYPE_STRING:
mValue.mString = new AString(*other.mValue.mString);
break;
case TYPE_OBJECT:
case TYPE_ARRAY:
mValue.mObjectOrArray->incStrong(this /* id */);
break;
default:
break;
}
}
return *this;
}
JSONValue::~JSONValue() {
unset();
}
JSONValue::FieldType JSONValue::type() const {
return mType;
}
bool JSONValue::getInt32(int32_t *value) const {
if (mType != TYPE_INT32) {
return false;
}
*value = mValue.mInt32;
return true;
}
bool JSONValue::getFloat(float *value) const {
switch (mType) {
case TYPE_INT32:
{
*value = mValue.mInt32;
break;
}
case TYPE_FLOAT:
{
*value = mValue.mFloat;
break;
}
default:
return false;
}
return true;
}
bool JSONValue::getString(AString *value) const {
if (mType != TYPE_STRING) {
return false;
}
*value = *mValue.mString;
return true;
}
bool JSONValue::getBoolean(bool *value) const {
if (mType != TYPE_BOOLEAN) {
return false;
}
*value = mValue.mBoolean;
return true;
}
bool JSONValue::getObject(sp<JSONObject> *value) const {
if (mType != TYPE_OBJECT) {
return false;
}
*value = static_cast<JSONObject *>(mValue.mObjectOrArray);
return true;
}
bool JSONValue::getArray(sp<JSONArray> *value) const {
if (mType != TYPE_ARRAY) {
return false;
}
*value = static_cast<JSONArray *>(mValue.mObjectOrArray);
return true;
}
void JSONValue::setInt32(int32_t value) {
unset();
mValue.mInt32 = value;
mType = TYPE_INT32;
}
void JSONValue::setFloat(float value) {
unset();
mValue.mFloat = value;
mType = TYPE_FLOAT;
}
void JSONValue::setString(const AString &value) {
unset();
mValue.mString = new AString(value);
mType = TYPE_STRING;
}
void JSONValue::setBoolean(bool value) {
unset();
mValue.mBoolean = value;
mType = TYPE_BOOLEAN;
}
void JSONValue::setObject(const sp<JSONObject> &obj) {
unset();
mValue.mObjectOrArray = obj.get();
mValue.mObjectOrArray->incStrong(this /* id */);
mType = TYPE_OBJECT;
}
void JSONValue::setArray(const sp<JSONArray> &array) {
unset();
mValue.mObjectOrArray = array.get();
mValue.mObjectOrArray->incStrong(this /* id */);
mType = TYPE_ARRAY;
}
void JSONValue::unset() {
switch (mType) {
case TYPE_STRING:
delete mValue.mString;
break;
case TYPE_OBJECT:
case TYPE_ARRAY:
mValue.mObjectOrArray->decStrong(this /* id */);
break;
default:
break;
}
mType = TYPE_NULL;
}
static void EscapeString(const char *in, size_t inSize, AString *out) {
CHECK(in != out->c_str());
out->clear();
for (size_t i = 0; i < inSize; ++i) {
char c = in[i];
switch (c) {
case '\"':
out->append("\\\"");
break;
case '\\':
out->append("\\\\");
break;
case '/':
out->append("\\/");
break;
case '\x08':
out->append("\\b");
break;
case '\x0c':
out->append("\\f");
break;
case '\x0a':
out->append("\\n");
break;
case '\x0d':
out->append("\\r");
break;
case '\x09':
out->append("\\t");
break;
default:
out->append(c);
break;
}
}
}
AString JSONValue::toString(size_t depth, bool indentFirstLine) const {
static const char kIndent[] = " ";
AString out;
switch (mType) {
case TYPE_STRING:
{
AString escaped;
EscapeString(
mValue.mString->c_str(), mValue.mString->size(), &escaped);
out.append("\"");
out.append(escaped);
out.append("\"");
break;
}
case TYPE_INT32:
{
out = AStringPrintf("%d", mValue.mInt32);
break;
}
case TYPE_FLOAT:
{
out = AStringPrintf("%f", mValue.mFloat);
break;
}
case TYPE_BOOLEAN:
{
out = mValue.mBoolean ? "true" : "false";
break;
}
case TYPE_NULL:
{
out = "null";
break;
}
case TYPE_OBJECT:
case TYPE_ARRAY:
{
out = (mType == TYPE_OBJECT) ? "{\n" : "[\n";
out.append(mValue.mObjectOrArray->internalToString(depth + 1));
out.append("\n");
out.append(kIndent, 2 * depth);
out.append(mType == TYPE_OBJECT ? "}" : "]");
break;
}
default:
TRESPASS();
}
if (indentFirstLine) {
out.insert(kIndent, 2 * depth, 0);
}
return out;
}
////////////////////////////////////////////////////////////////////////////////
// static
sp<JSONCompound> JSONCompound::Parse(const char *data, size_t size) {
JSONValue value;
ssize_t result = JSONValue::Parse(data, size, &value);
if (result < 0) {
return NULL;
}
sp<JSONObject> obj;
if (value.getObject(&obj)) {
return obj;
}
sp<JSONArray> array;
if (value.getArray(&array)) {
return array;
}
return NULL;
}
AString JSONCompound::toString(size_t depth, bool indentFirstLine) const {
JSONValue val;
if (isObject()) {
val.setObject((JSONObject *)this);
} else {
val.setArray((JSONArray *)this);
}
return val.toString(depth, indentFirstLine);
}
////////////////////////////////////////////////////////////////////////////////
JSONObject::JSONObject() {}
JSONObject::~JSONObject() {}
bool JSONObject::isObject() const {
return true;
}
bool JSONObject::getValue(const char *key, JSONValue *value) const {
ssize_t index = mValues.indexOfKey(key);
if (index < 0) {
return false;
}
*value = mValues.valueAt(index);
return true;
}
void JSONObject::setValue(const char *key, const JSONValue &value) {
mValues.add(AString(key), value);
}
AString JSONObject::internalToString(size_t depth) const {
static const char kIndent[] = " ";
AString out;
for (size_t i = 0; i < mValues.size(); ++i) {
AString key = mValues.keyAt(i);
AString escapedKey;
EscapeString(key.c_str(), key.size(), &escapedKey);
out.append(kIndent, 2 * depth);
out.append("\"");
out.append(escapedKey);
out.append("\": ");
out.append(mValues.valueAt(i).toString(depth + 1, false));
if (i + 1 < mValues.size()) {
out.append(",\n");
}
}
return out;
}
////////////////////////////////////////////////////////////////////////////////
JSONArray::JSONArray() {}
JSONArray::~JSONArray() {}
bool JSONArray::isObject() const {
return false;
}
size_t JSONArray::size() const {
return mValues.size();
}
bool JSONArray::getValue(size_t key, JSONValue *value) const {
if (key >= mValues.size()) {
return false;
}
*value = mValues.itemAt(key);
return true;
}
void JSONArray::addValue(const JSONValue &value) {
mValues.push_back(value);
}
AString JSONArray::internalToString(size_t depth) const {
AString out;
for (size_t i = 0; i < mValues.size(); ++i) {
out.append(mValues.itemAt(i).toString(depth));
if (i + 1 < mValues.size()) {
out.append(",\n");
}
}
return out;
}
////////////////////////////////////////////////////////////////////////////////
} // namespace android