llvm-project/lldb/source/Utility/JSON.cpp

654 lines
18 KiB
C++

//===--------------------- JSON.cpp -----------------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "lldb/Utility/JSON.h"
#include <limits.h>
#include "lldb/Core/StreamString.h"
#include "lldb/Host/StringConvert.h"
using namespace lldb_private;
std::string
JSONString::json_string_quote_metachars (const std::string &s)
{
if (s.find('"') == std::string::npos)
return s;
std::string output;
const size_t s_size = s.size();
const char *s_chars = s.c_str();
for (size_t i = 0; i < s_size; i++)
{
unsigned char ch = *(s_chars + i);
if (ch == '"')
{
output.push_back ('\\');
}
output.push_back (ch);
}
return output;
}
JSONString::JSONString () :
JSONValue(JSONValue::Kind::String),
m_data()
{
}
JSONString::JSONString (const char* s) :
JSONValue(JSONValue::Kind::String),
m_data(s ? s : "")
{
}
JSONString::JSONString (const std::string& s) :
JSONValue(JSONValue::Kind::String),
m_data(s)
{
}
void
JSONString::Write (Stream& s)
{
s.Printf("\"%s\"", json_string_quote_metachars(m_data).c_str());
}
JSONNumber::JSONNumber () :
JSONValue(JSONValue::Kind::Number),
m_is_integer(true),
m_data(0),
m_double(0.0)
{
}
JSONNumber::JSONNumber (uint64_t i) :
JSONValue(JSONValue::Kind::Number),
m_is_integer(true),
m_data(i),
m_double(0.0)
{
}
JSONNumber::JSONNumber (double d) :
JSONValue(JSONValue::Kind::Number),
m_is_integer(false),
m_data(0),
m_double(d)
{
}
void
JSONNumber::Write (Stream& s)
{
if (m_is_integer)
s.Printf("%" PRIu64, m_data);
else
s.Printf("%g", m_double);
}
JSONTrue::JSONTrue () :
JSONValue(JSONValue::Kind::True)
{
}
void
JSONTrue::Write(Stream& s)
{
s.Printf("true");
}
JSONFalse::JSONFalse () :
JSONValue(JSONValue::Kind::False)
{
}
void
JSONFalse::Write(Stream& s)
{
s.Printf("false");
}
JSONNull::JSONNull () :
JSONValue(JSONValue::Kind::Null)
{
}
void
JSONNull::Write(Stream& s)
{
s.Printf("null");
}
JSONObject::JSONObject () :
JSONValue(JSONValue::Kind::Object)
{
}
void
JSONObject::Write (Stream& s)
{
bool first = true;
s.PutChar('{');
auto iter = m_elements.begin(), end = m_elements.end();
for (;iter != end; iter++)
{
if (first)
first = false;
else
s.PutChar(',');
JSONString key(iter->first);
JSONValue::SP value(iter->second);
key.Write(s);
s.PutChar(':');
value->Write(s);
}
s.PutChar('}');
}
bool
JSONObject::SetObject (const std::string& key,
JSONValue::SP value)
{
if (key.empty() || nullptr == value.get())
return false;
m_elements[key] = value;
return true;
}
JSONValue::SP
JSONObject::GetObject (const std::string& key)
{
auto iter = m_elements.find(key), end = m_elements.end();
if (iter == end)
return JSONValue::SP();
return iter->second;
}
JSONArray::JSONArray () :
JSONValue(JSONValue::Kind::Array)
{
}
void
JSONArray::Write (Stream& s)
{
bool first = true;
s.PutChar('[');
auto iter = m_elements.begin(), end = m_elements.end();
for (;iter != end; iter++)
{
if (first)
first = false;
else
s.PutChar(',');
(*iter)->Write(s);
}
s.PutChar(']');
}
bool
JSONArray::SetObject (Index i,
JSONValue::SP value)
{
if (value.get() == nullptr)
return false;
if (i < m_elements.size())
{
m_elements[i] = value;
return true;
}
if (i == m_elements.size())
{
m_elements.push_back(value);
return true;
}
return false;
}
bool
JSONArray::AppendObject (JSONValue::SP value)
{
if (value.get() == nullptr)
return false;
m_elements.push_back(value);
return true;
}
JSONValue::SP
JSONArray::GetObject (Index i)
{
if (i < m_elements.size())
return m_elements[i];
return JSONValue::SP();
}
JSONArray::Size
JSONArray::GetNumElements ()
{
return m_elements.size();
}
JSONParser::JSONParser (const char *cstr) :
StringExtractor(cstr)
{
}
JSONParser::Token
JSONParser::GetToken (std::string &value)
{
StreamString error;
value.clear();
SkipSpaces ();
const uint64_t start_index = m_index;
const char ch = GetChar();
switch (ch)
{
case '{': return Token::ObjectStart;
case '}': return Token::ObjectEnd;
case '[': return Token::ArrayStart;
case ']': return Token::ArrayEnd;
case ',': return Token::Comma;
case ':': return Token::Colon;
case '\0': return Token::EndOfFile;
case 't':
if (GetChar() == 'r')
if (GetChar() == 'u')
if (GetChar() == 'e')
return Token::True;
break;
case 'f':
if (GetChar() == 'a')
if (GetChar() == 'l')
if (GetChar() == 's')
if (GetChar() == 'e')
return Token::False;
break;
case 'n':
if (GetChar() == 'u')
if (GetChar() == 'l')
if (GetChar() == 'l')
return Token::Null;
break;
case '"':
{
while (1)
{
bool was_escaped = false;
int escaped_ch = GetEscapedChar(was_escaped);
if (escaped_ch == -1)
{
error.Printf("error: an error occurred getting a character from offset %" PRIu64, start_index);
value = std::move(error.GetString());
return Token::Error;
}
else
{
const bool is_end_quote = escaped_ch == '"';
const bool is_null = escaped_ch == 0;
if (was_escaped || (!is_end_quote && !is_null))
{
if (CHAR_MIN <= escaped_ch && escaped_ch <= CHAR_MAX)
{
value.append(1, (char)escaped_ch);
}
else
{
error.Printf("error: wide character support is needed for unicode character 0x%4.4x at offset %" PRIu64, escaped_ch, start_index);
value = std::move(error.GetString());
return Token::Error;
}
}
else if (is_end_quote)
{
return Token::String;
}
else if (is_null)
{
value = "error: missing end quote for string";
return Token::Error;
}
}
}
}
break;
case '-':
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
{
bool done = false;
bool got_decimal_point = false;
uint64_t exp_index = 0;
bool got_int_digits = (ch >= '0') && (ch <= '9');
bool got_frac_digits = false;
bool got_exp_digits = false;
while (!done)
{
const char next_ch = PeekChar();
switch (next_ch)
{
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
if (exp_index != 0)
{
got_exp_digits = true;
}
else if (got_decimal_point)
{
got_frac_digits = true;
}
else
{
got_int_digits = true;
}
++m_index; // Skip this character
break;
case '.':
if (got_decimal_point)
{
error.Printf("error: extra decimal point found at offset %" PRIu64, start_index);
value = std::move(error.GetString());
return Token::Error;
}
else
{
got_decimal_point = true;
++m_index; // Skip this character
}
break;
case 'e':
case 'E':
if (exp_index != 0)
{
error.Printf("error: extra exponent character found at offset %" PRIu64, start_index);
value = std::move(error.GetString());
return Token::Error;
}
else
{
exp_index = m_index;
++m_index; // Skip this character
}
break;
case '+':
case '-':
// The '+' and '-' can only come after an exponent character...
if (exp_index == m_index - 1)
{
++m_index; // Skip the exponent sign character
}
else
{
error.Printf("error: unexpected %c character at offset %" PRIu64, next_ch, start_index);
value = std::move(error.GetString());
return Token::Error;
}
default:
done = true;
break;
}
}
if (m_index > start_index)
{
value = m_packet.substr(start_index, m_index - start_index);
if (got_decimal_point)
{
if (exp_index != 0)
{
// We have an exponent, make sure we got exponent digits
if (got_exp_digits)
{
return Token::Float;
}
else
{
error.Printf("error: got exponent character but no exponent digits at offset in float value \"%s\"", value.c_str());
value = std::move(error.GetString());
return Token::Error;
}
}
else
{
// No exponent, but we need at least one decimal after the decimal point
if (got_frac_digits)
{
return Token::Float;
}
else
{
error.Printf("error: no digits after decimal point \"%s\"", value.c_str());
value = std::move(error.GetString());
return Token::Error;
}
}
}
else
{
// No decimal point
if (got_int_digits)
{
// We need at least some integer digits to make an integer
return Token::Integer;
}
else
{
error.Printf("error: no digits negate sign \"%s\"", value.c_str());
value = std::move(error.GetString());
return Token::Error;
}
}
}
else
{
error.Printf("error: invalid number found at offset %" PRIu64, start_index);
value = std::move(error.GetString());
return Token::Error;
}
}
break;
default:
break;
}
error.Printf("error: failed to parse token at offset %" PRIu64 " (around character '%c')", start_index, ch);
value = std::move(error.GetString());
return Token::Error;
}
int
JSONParser::GetEscapedChar(bool &was_escaped)
{
was_escaped = false;
const char ch = GetChar();
if (ch == '\\')
{
was_escaped = true;
const char ch2 = GetChar();
switch (ch2)
{
case '"':
case '\\':
case '/':
default:
break;
case 'b': return '\b';
case 'f': return '\f';
case 'n': return '\n';
case 'r': return '\r';
case 't': return '\t';
case 'u':
{
const int hi_byte = DecodeHexU8();
const int lo_byte = DecodeHexU8();
if (hi_byte >=0 && lo_byte >= 0)
return hi_byte << 8 | lo_byte;
return -1;
}
break;
}
return ch2;
}
return ch;
}
JSONValue::SP
JSONParser::ParseJSONObject ()
{
// The "JSONParser::Token::ObjectStart" token should have already been consumed
// by the time this function is called
std::unique_ptr<JSONObject> dict_up(new JSONObject());
std::string value;
std::string key;
while (1)
{
JSONParser::Token token = GetToken(value);
if (token == JSONParser::Token::String)
{
key.swap(value);
token = GetToken(value);
if (token == JSONParser::Token::Colon)
{
JSONValue::SP value_sp = ParseJSONValue();
if (value_sp)
dict_up->SetObject(key, value_sp);
else
break;
}
}
else if (token == JSONParser::Token::ObjectEnd)
{
return JSONValue::SP(dict_up.release());
}
else if (token == JSONParser::Token::Comma)
{
continue;
}
else
{
break;
}
}
return JSONValue::SP();
}
JSONValue::SP
JSONParser::ParseJSONArray ()
{
// The "JSONParser::Token::ObjectStart" token should have already been consumed
// by the time this function is called
std::unique_ptr<JSONArray> array_up(new JSONArray());
std::string value;
std::string key;
while (1)
{
JSONValue::SP value_sp = ParseJSONValue();
if (value_sp)
array_up->AppendObject(value_sp);
else
break;
JSONParser::Token token = GetToken(value);
if (token == JSONParser::Token::Comma)
{
continue;
}
else if (token == JSONParser::Token::ArrayEnd)
{
return JSONValue::SP(array_up.release());
}
else
{
break;
}
}
return JSONValue::SP();
}
JSONValue::SP
JSONParser::ParseJSONValue ()
{
std::string value;
const JSONParser::Token token = GetToken(value);
switch (token)
{
case JSONParser::Token::ObjectStart:
return ParseJSONObject();
case JSONParser::Token::ArrayStart:
return ParseJSONArray();
case JSONParser::Token::Integer:
{
bool success = false;
uint64_t uval = StringConvert::ToUInt64(value.c_str(), 0, 0, &success);
if (success)
return JSONValue::SP(new JSONNumber(uval));
}
break;
case JSONParser::Token::Float:
{
bool success = false;
double val = StringConvert::ToDouble(value.c_str(), 0.0, &success);
if (success)
return JSONValue::SP(new JSONNumber(val));
}
break;
case JSONParser::Token::String:
return JSONValue::SP(new JSONString(value));
case JSONParser::Token::True:
return JSONValue::SP(new JSONTrue());
case JSONParser::Token::False:
return JSONValue::SP(new JSONFalse());
case JSONParser::Token::Null:
return JSONValue::SP(new JSONNull());
default:
break;
}
return JSONValue::SP();
}