lix/src/libstore/derivations.cc
Eelco Dolstra 6bbfe95e30 * Don't use an ostringstream in unparseDerivation(), because it's
slow.  A `nix-env -qa --drv-path \*' on Nixpkgs was spending 40% of
  its time in unparseDerivation() because of this (now 11%).
2010-04-21 19:25:50 +00:00

175 lines
4.6 KiB
C++

#include "derivations.hh"
#include "store-api.hh"
#include "globals.hh"
#include "util.hh"
namespace nix {
Path writeDerivation(const Derivation & drv, const string & name)
{
PathSet references;
references.insert(drv.inputSrcs.begin(), drv.inputSrcs.end());
foreach (DerivationInputs::const_iterator, i, drv.inputDrvs)
references.insert(i->first);
/* Note that the outputs of a derivation are *not* references
(that can be missing (of course) and should not necessarily be
held during a garbage collection). */
string suffix = name + drvExtension;
string contents = unparseDerivation(drv);
return readOnlyMode
? computeStorePathForText(suffix, contents, references)
: store->addTextToStore(suffix, contents, references);
}
static Path parsePath(std::istream & str)
{
string s = parseString(str);
if (s.size() == 0 || s[0] != '/')
throw Error(format("bad path `%1%' in derivation") % s);
return s;
}
static StringSet parseStrings(std::istream & str, bool arePaths)
{
StringSet res;
while (!endOfList(str))
res.insert(arePaths ? parsePath(str) : parseString(str));
return res;
}
Derivation parseDerivation(const string & s)
{
Derivation drv;
std::istringstream str(s);
expect(str, "Derive([");
/* Parse the list of outputs. */
while (!endOfList(str)) {
DerivationOutput out;
expect(str, "("); string id = parseString(str);
expect(str, ","); out.path = parsePath(str);
expect(str, ","); out.hashAlgo = parseString(str);
expect(str, ","); out.hash = parseString(str);
expect(str, ")");
drv.outputs[id] = out;
}
/* Parse the list of input derivations. */
expect(str, ",[");
while (!endOfList(str)) {
expect(str, "(");
Path drvPath = parsePath(str);
expect(str, ",[");
drv.inputDrvs[drvPath] = parseStrings(str, false);
expect(str, ")");
}
expect(str, ",["); drv.inputSrcs = parseStrings(str, true);
expect(str, ","); drv.platform = parseString(str);
expect(str, ","); drv.builder = parseString(str);
/* Parse the builder arguments. */
expect(str, ",[");
while (!endOfList(str))
drv.args.push_back(parseString(str));
/* Parse the environment variables. */
expect(str, ",[");
while (!endOfList(str)) {
expect(str, "("); string name = parseString(str);
expect(str, ","); string value = parseString(str);
expect(str, ")");
drv.env[name] = value;
}
expect(str, ")");
return drv;
}
static void printString(string & res, const string & s)
{
res += '"';
for (const char * i = s.c_str(); *i; i++)
if (*i == '\"' || *i == '\\') { res += "\\"; res += *i; }
else if (*i == '\n') res += "\\n";
else if (*i == '\r') res += "\\r";
else if (*i == '\t') res += "\\t";
else res += *i;
res += '"';
}
template<class ForwardIterator>
static void printStrings(string & res, ForwardIterator i, ForwardIterator j)
{
res += '[';
bool first = true;
for ( ; i != j; ++i) {
if (first) first = false; else res += ',';
printString(res, *i);
}
res += ']';
}
string unparseDerivation(const Derivation & drv)
{
string s;
s.reserve(65536);
s += "Derive([";
bool first = true;
foreach (DerivationOutputs::const_iterator, i, drv.outputs) {
if (first) first = false; else s += ',';
s += '('; printString(s, i->first);
s += ','; printString(s, i->second.path);
s += ','; printString(s, i->second.hashAlgo);
s += ','; printString(s, i->second.hash);
s += ')';
}
s += "],[";
first = true;
foreach (DerivationInputs::const_iterator, i, drv.inputDrvs) {
if (first) first = false; else s += ',';
s += '('; printString(s, i->first);
s += ','; printStrings(s, i->second.begin(), i->second.end());
s += ')';
}
s += "],";
printStrings(s, drv.inputSrcs.begin(), drv.inputSrcs.end());
s += ','; printString(s, drv.platform);
s += ','; printString(s, drv.builder);
s += ','; printStrings(s, drv.args.begin(), drv.args.end());
s += ",[";
first = true;
foreach (StringPairs::const_iterator, i, drv.env) {
if (first) first = false; else s += ',';
s += '('; printString(s, i->first);
s += ','; printString(s, i->second);
s += ')';
}
s += "])";
return s;
}
bool isDerivation(const string & fileName)
{
return hasSuffix(fileName, drvExtension);
}
}