lix/src/libutil/json.cc
2016-10-06 17:00:52 +02:00

187 lines
3.1 KiB
C++

#include "json.hh"
#include <iomanip>
#include <cstring>
namespace nix {
void toJSON(std::ostream & str, const char * start, const char * end)
{
str << '"';
for (auto i = start; i != end; i++)
if (*i == '\"' || *i == '\\') str << '\\' << *i;
else if (*i == '\n') str << "\\n";
else if (*i == '\r') str << "\\r";
else if (*i == '\t') str << "\\t";
else if (*i >= 0 && *i < 32)
str << "\\u" << std::setfill('0') << std::setw(4) << std::hex << (uint16_t) *i << std::dec;
else str << *i;
str << '"';
}
void toJSON(std::ostream & str, const std::string & s)
{
toJSON(str, s.c_str(), s.c_str() + s.size());
}
void toJSON(std::ostream & str, const char * s)
{
if (!s) str << "null"; else toJSON(str, s, s + strlen(s));
}
void toJSON(std::ostream & str, unsigned long long n)
{
str << n;
}
void toJSON(std::ostream & str, unsigned long n)
{
str << n;
}
void toJSON(std::ostream & str, long n)
{
str << n;
}
void toJSON(std::ostream & str, unsigned int n)
{
str << n;
}
void toJSON(std::ostream & str, int n)
{
str << n;
}
void toJSON(std::ostream & str, double f)
{
str << f;
}
void toJSON(std::ostream & str, bool b)
{
str << (b ? "true" : "false");
}
JSONWriter::JSONWriter(std::ostream & str, bool indent)
: state(new JSONState(str, indent))
{
state->stack.push_back(this);
}
JSONWriter::JSONWriter(JSONState * state)
: state(state)
{
state->stack.push_back(this);
}
JSONWriter::~JSONWriter()
{
assertActive();
state->stack.pop_back();
if (state->stack.empty()) delete state;
}
void JSONWriter::comma()
{
assertActive();
if (first) {
first = false;
} else {
state->str << ',';
}
if (state->indent) indent();
}
void JSONWriter::indent()
{
state->str << '\n' << std::string(state->depth * 2, ' ');
}
void JSONList::open()
{
state->depth++;
state->str << '[';
}
JSONList::~JSONList()
{
state->depth--;
if (state->indent && !first) indent();
state->str << "]";
}
JSONList JSONList::list()
{
comma();
return JSONList(state);
}
JSONObject JSONList::object()
{
comma();
return JSONObject(state);
}
JSONPlaceholder JSONList::placeholder()
{
comma();
return JSONPlaceholder(state);
}
void JSONObject::open()
{
state->depth++;
state->str << '{';
}
JSONObject::~JSONObject()
{
state->depth--;
if (state->indent && !first) indent();
state->str << "}";
}
void JSONObject::attr(const std::string & s)
{
comma();
toJSON(state->str, s);
state->str << ':';
if (state->indent) state->str << ' ';
}
JSONList JSONObject::list(const std::string & name)
{
attr(name);
return JSONList(state);
}
JSONObject JSONObject::object(const std::string & name)
{
attr(name);
return JSONObject(state);
}
JSONPlaceholder JSONObject::placeholder(const std::string & name)
{
attr(name);
return JSONPlaceholder(state);
}
JSONList JSONPlaceholder::list()
{
assertValid();
first = false;
return JSONList(state);
}
JSONObject JSONPlaceholder::object()
{
assertValid();
first = false;
return JSONObject(state);
}
}