lix/src/libexpr/expr-to-xml.cc
Eelco Dolstra 5011588459 * printTermAsXML: treat derivations specially; emit an element
<derivation outPath=... drvPath=...> attrs </derivation>.  Only emit
  the attributes of any specific derivation only.  This prevents
  exponententially large XML output due to the absense of sharing.
2007-01-13 15:11:10 +00:00

143 lines
3.9 KiB
C++

#include "expr-to-xml.hh"
#include "xml-writer.hh"
#include "nixexpr-ast.hh"
#include "aterm.hh"
#include "util.hh"
namespace nix {
static XMLAttrs singletonAttrs(const string & name, const string & value)
{
XMLAttrs attrs;
attrs[name] = value;
return attrs;
}
/* set<Expr> is safe because all the expressions are also reachable
from the stack, therefore can't be garbage-collected. */
typedef set<Expr> ExprSet;
static void printTermAsXML(Expr e, XMLWriter & doc, PathSet & context,
ExprSet & drvsSeen);
static void showAttrs(const ATermMap & attrs, XMLWriter & doc,
PathSet & context, ExprSet & drvsSeen)
{
StringSet names;
for (ATermMap::const_iterator i = attrs.begin(); i != attrs.end(); ++i)
names.insert(aterm2String(i->key));
for (StringSet::iterator i = names.begin(); i != names.end(); ++i) {
XMLOpenElement _(doc, "attr", singletonAttrs("name", *i));
printTermAsXML(attrs.get(toATerm(*i)), doc, context, drvsSeen);
}
}
static void printTermAsXML(Expr e, XMLWriter & doc, PathSet & context,
ExprSet & drvsSeen)
{
XMLAttrs attrs;
string s;
ATerm s2;
int i;
ATermList as, es, formals;
ATerm body, pos;
checkInterrupt();
if (matchStr(e, s, context)) /* !!! show the context? */
doc.writeEmptyElement("string", singletonAttrs("value", s));
else if (matchPath(e, s2))
doc.writeEmptyElement("path", singletonAttrs("value", aterm2String(s2)));
else if (matchNull(e))
doc.writeEmptyElement("null");
else if (matchInt(e, i))
doc.writeEmptyElement("int", singletonAttrs("value", (format("%1%") % i).str()));
else if (e == eTrue)
doc.writeEmptyElement("bool", singletonAttrs("value", "true"));
else if (e == eFalse)
doc.writeEmptyElement("bool", singletonAttrs("value", "false"));
else if (matchAttrs(e, as)) {
ATermMap attrs;
queryAllAttrs(e, attrs);
Expr a = attrs.get(toATerm("type"));
if (a && matchStr(a, s, context) && s == "derivation") {
XMLAttrs xmlAttrs;
Path outPath, drvPath;
a = attrs.get(toATerm("drvPath"));
if (matchStr(a, drvPath, context))
xmlAttrs["drvPath"] = drvPath;
a = attrs.get(toATerm("outPath"));
if (matchStr(a, outPath, context))
xmlAttrs["outPath"] = outPath;
XMLOpenElement _(doc, "derivation", xmlAttrs);
if (drvsSeen.find(e) == drvsSeen.end()) {
drvsSeen.insert(e);
showAttrs(attrs, doc, context, drvsSeen);
} else
doc.writeEmptyElement("repeated");
}
else {
XMLOpenElement _(doc, "attrs");
showAttrs(attrs, doc, context, drvsSeen);
}
}
else if (matchList(e, es)) {
XMLOpenElement _(doc, "list");
for (ATermIterator i(es); i; ++i)
printTermAsXML(*i, doc, context, drvsSeen);
}
else if (matchFunction(e, formals, body, pos)) {
XMLOpenElement _(doc, "function");
for (ATermIterator i(formals); i; ++i) {
Expr name; ValidValues valids; ATerm dummy;
if (!matchFormal(*i, name, valids, dummy)) abort();
XMLOpenElement _(doc, "arg", singletonAttrs("name", aterm2String(name)));
ATermList valids2;
if (matchValidValues(valids, valids2)) {
for (ATermIterator j(valids2); j; ++j) {
XMLOpenElement _(doc, "value");
printTermAsXML(*j, doc, context, drvsSeen);
}
}
}
}
else
doc.writeEmptyElement("unevaluated");
}
void printTermAsXML(Expr e, std::ostream & out, PathSet & context)
{
XMLWriter doc(true, out);
XMLOpenElement root(doc, "expr");
ExprSet drvsSeen;
printTermAsXML(e, doc, context, drvsSeen);
}
}