lix/src/libexpr/value-to-xml.cc
Eelco Dolstra 0b305c534f * Store attribute sets as a vector instead of a map (i.e. a red-black
tree).  This saves a lot of memory.  The vector should be sorted so
  that names can be looked up using binary search, but this is not the
  case yet.  (Surprisingly, looking up attributes using linear search
  doesn't have a big impact on performance.)

  Memory consumption for

    $ nix-instantiate /etc/nixos/nixos/tests -A bittorrent.test --readonly-mode

  on x86_64-linux with GC enabled is now 185 MiB (compared to 946
  MiB on the trunk).
2010-10-24 00:41:29 +00:00

163 lines
4.9 KiB
C++

#include "value-to-xml.hh"
#include "xml-writer.hh"
#include "util.hh"
#include <cstdlib>
namespace nix {
static XMLAttrs singletonAttrs(const string & name, const string & value)
{
XMLAttrs attrs;
attrs[name] = value;
return attrs;
}
static void printValueAsXML(EvalState & state, bool strict, bool location,
Value & v, XMLWriter & doc, PathSet & context, PathSet & drvsSeen);
static void posToXML(XMLAttrs & xmlAttrs, const Pos & pos)
{
xmlAttrs["path"] = pos.file;
xmlAttrs["line"] = (format("%1%") % pos.line).str();
xmlAttrs["column"] = (format("%1%") % pos.column).str();
}
static void showAttrs(EvalState & state, bool strict, bool location,
Bindings & attrs, XMLWriter & doc, PathSet & context, PathSet & drvsSeen)
{
StringSet names;
foreach (Bindings::iterator, i, attrs)
names.insert(i->name);
foreach (StringSet::iterator, i, names) {
Attr & a(attrs[state.symbols.create(*i)]);
XMLAttrs xmlAttrs;
xmlAttrs["name"] = *i;
if (location && a.pos != &noPos) posToXML(xmlAttrs, *a.pos);
XMLOpenElement _(doc, "attr", xmlAttrs);
printValueAsXML(state, strict, location,
*a.value, doc, context, drvsSeen);
}
}
static void printValueAsXML(EvalState & state, bool strict, bool location,
Value & v, XMLWriter & doc, PathSet & context, PathSet & drvsSeen)
{
checkInterrupt();
if (strict) state.forceValue(v);
switch (v.type) {
case tInt:
doc.writeEmptyElement("int", singletonAttrs("value", (format("%1%") % v.integer).str()));
break;
case tBool:
doc.writeEmptyElement("bool", singletonAttrs("value", v.boolean ? "true" : "false"));
break;
case tString:
/* !!! show the context? */
copyContext(v, context);
doc.writeEmptyElement("string", singletonAttrs("value", v.string.s));
break;
case tPath:
doc.writeEmptyElement("path", singletonAttrs("value", v.path));
break;
case tNull:
doc.writeEmptyElement("null");
break;
case tAttrs:
if (state.isDerivation(v)) {
XMLAttrs xmlAttrs;
Bindings::iterator a = v.attrs->find(state.symbols.create("derivation"));
Path drvPath;
a = v.attrs->find(state.sDrvPath);
if (a != v.attrs->end()) {
if (strict) state.forceValue(*a->value);
if (a->value->type == tString)
xmlAttrs["drvPath"] = drvPath = a->value->string.s;
}
a = v.attrs->find(state.sOutPath);
if (a != v.attrs->end()) {
if (strict) state.forceValue(*a->value);
if (a->value->type == tString)
xmlAttrs["outPath"] = a->value->string.s;
}
XMLOpenElement _(doc, "derivation", xmlAttrs);
if (drvPath != "" && drvsSeen.find(drvPath) == drvsSeen.end()) {
drvsSeen.insert(drvPath);
showAttrs(state, strict, location, *v.attrs, doc, context, drvsSeen);
} else
doc.writeEmptyElement("repeated");
}
else {
XMLOpenElement _(doc, "attrs");
showAttrs(state, strict, location, *v.attrs, doc, context, drvsSeen);
}
break;
case tList: {
XMLOpenElement _(doc, "list");
for (unsigned int n = 0; n < v.list.length; ++n)
printValueAsXML(state, strict, location, *v.list.elems[n], doc, context, drvsSeen);
break;
}
case tLambda: {
XMLAttrs xmlAttrs;
if (location) posToXML(xmlAttrs, v.lambda.fun->pos);
XMLOpenElement _(doc, "function", xmlAttrs);
if (v.lambda.fun->matchAttrs) {
XMLAttrs attrs;
if (!v.lambda.fun->arg.empty()) attrs["name"] = v.lambda.fun->arg;
if (v.lambda.fun->formals->ellipsis) attrs["ellipsis"] = "1";
XMLOpenElement _(doc, "attrspat", attrs);
foreach (Formals::Formals_::iterator, i, v.lambda.fun->formals->formals)
doc.writeEmptyElement("attr", singletonAttrs("name", i->name));
} else
doc.writeEmptyElement("varpat", singletonAttrs("name", v.lambda.fun->arg));
break;
}
default:
doc.writeEmptyElement("unevaluated");
}
}
void printValueAsXML(EvalState & state, bool strict, bool location,
Value & v, std::ostream & out, PathSet & context)
{
XMLWriter doc(true, out);
XMLOpenElement root(doc, "expr");
PathSet drvsSeen;
printValueAsXML(state, strict, location, v, doc, context, drvsSeen);
}
}