guix/src/libexpr/value-to-json.cc

94 lines
2.4 KiB
C++

#include "value-to-xml.hh"
#include "xml-writer.hh"
#include "eval-inline.hh"
#include "util.hh"
#include <cstdlib>
namespace nix {
static void escapeJSON(std::ostream & str, const string & s)
{
str << "\"";
foreach (string::const_iterator, i, s)
if (*i == '\"' || *i == '\\') str << "\\" << *i;
else if (*i == '\n') str << "\\n";
else if (*i == '\r') str << "\\r";
else if (*i == '\t') str << "\\t";
else str << *i;
str << "\"";
}
void printValueAsJSON(EvalState & state, bool strict,
Value & v, std::ostream & str, PathSet & context)
{
checkInterrupt();
if (strict) state.forceValue(v);
switch (v.type) {
case tInt:
str << v.integer;
break;
case tBool:
str << (v.boolean ? "true" : "false");
break;
case tString:
copyContext(v, context);
escapeJSON(str, v.string.s);
break;
case tPath:
escapeJSON(str, state.copyPathToStore(context, v.path));
break;
case tNull:
str << "null";
break;
case tAttrs: {
Bindings::iterator i = v.attrs->find(state.sOutPath);
if (i == v.attrs->end()) {
str << "{";
StringSet names;
foreach (Bindings::iterator, i, *v.attrs)
names.insert(i->name);
bool first = true;
foreach (StringSet::iterator, i, names) {
if (!first) str << ","; else first = false;
Attr & a(*v.attrs->find(state.symbols.create(*i)));
escapeJSON(str, *i);
str << ":";
printValueAsJSON(state, strict, *a.value, str, context);
}
str << "}";
} else
printValueAsJSON(state, strict, *i->value, str, context);
break;
}
case tList: {
str << "[";
bool first = true;
for (unsigned int n = 0; n < v.list.length; ++n) {
if (!first) str << ","; else first = false;
printValueAsJSON(state, strict, *v.list.elems[n], str, context);
}
str << "]";
break;
}
default:
throw TypeError(format("cannot convert %1% to JSON") % showType(v));
}
}
}