lix/src/libstore/derivations.cc
Eelco Dolstra d7efd76394 * Big cleanup of the semantics of paths, strings, contexts, string
concatenation and string coercion.  This was a big mess (see
  e.g. NIX-67).  Contexts are now folded into strings, so that they
  don't cause evaluation errors when they're not expected.  The
  semantics of paths has been clarified (see nixexpr-ast.def).
  toString() and coerceToString() have been merged.

  Semantic change: paths are now copied to the store when they're in a
  concatenation (and in most other situations - that's the
  formalisation of the meaning of a path).  So

    "foo " + ./bla

  evaluates to "foo /nix/store/hash...-bla", not "foo
  /path/to/current-dir/bla".  This prevents accidental impurities, and
  is more consistent with the treatment of derivation outputs, e.g.,
  `"foo " + bla' where `bla' is a derivation.  (Here `bla' would be
  replaced by the output path of `bla'.)
2006-10-16 15:55:34 +00:00

168 lines
4.5 KiB
C++

#include "derivations.hh"
#include "store.hh"
#include "aterm.hh"
#include "derivations-ast.hh"
#include "derivations-ast.cc"
namespace nix {
Hash hashTerm(ATerm t)
{
return hashString(htSHA256, atPrint(t));
}
Path writeDerivation(const Derivation & drv, const string & name)
{
PathSet references;
references.insert(drv.inputSrcs.begin(), drv.inputSrcs.end());
for (DerivationInputs::const_iterator i = drv.inputDrvs.begin();
i != drv.inputDrvs.end(); ++i)
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). */
return addTextToStore(name + drvExtension,
atPrint(unparseDerivation(drv)), references);
}
static void checkPath(const string & s)
{
if (s.size() == 0 || s[0] != '/')
throw Error(format("bad path `%1%' in derivation") % s);
}
static void parseStrings(ATermList paths, StringSet & out, bool arePaths)
{
for (ATermIterator i(paths); i; ++i) {
if (ATgetType(*i) != AT_APPL)
throw badTerm("not a path", *i);
string s = aterm2String(*i);
if (arePaths) checkPath(s);
out.insert(s);
}
}
/* Shut up warnings. */
void throwBadDrv(ATerm t) __attribute__ ((noreturn));
void throwBadDrv(ATerm t)
{
throw badTerm("not a valid derivation", t);
}
Derivation parseDerivation(ATerm t)
{
Derivation drv;
ATermList outs, inDrvs, inSrcs, args, bnds;
ATerm builder, platform;
if (!matchDerive(t, outs, inDrvs, inSrcs, platform, builder, args, bnds))
throwBadDrv(t);
for (ATermIterator i(outs); i; ++i) {
ATerm id, path, hashAlgo, hash;
if (!matchDerivationOutput(*i, id, path, hashAlgo, hash))
throwBadDrv(t);
DerivationOutput out;
out.path = aterm2String(path);
checkPath(out.path);
out.hashAlgo = aterm2String(hashAlgo);
out.hash = aterm2String(hash);
drv.outputs[aterm2String(id)] = out;
}
for (ATermIterator i(inDrvs); i; ++i) {
ATerm drvPath;
ATermList ids;
if (!matchDerivationInput(*i, drvPath, ids))
throwBadDrv(t);
Path drvPath2 = aterm2String(drvPath);
checkPath(drvPath2);
StringSet ids2;
parseStrings(ids, ids2, false);
drv.inputDrvs[drvPath2] = ids2;
}
parseStrings(inSrcs, drv.inputSrcs, true);
drv.builder = aterm2String(builder);
drv.platform = aterm2String(platform);
for (ATermIterator i(args); i; ++i) {
if (ATgetType(*i) != AT_APPL)
throw badTerm("string expected", *i);
drv.args.push_back(aterm2String(*i));
}
for (ATermIterator i(bnds); i; ++i) {
ATerm s1, s2;
if (!matchEnvBinding(*i, s1, s2))
throw badTerm("tuple of strings expected", *i);
drv.env[aterm2String(s1)] = aterm2String(s2);
}
return drv;
}
ATerm unparseDerivation(const Derivation & drv)
{
ATermList outputs = ATempty;
for (DerivationOutputs::const_reverse_iterator i = drv.outputs.rbegin();
i != drv.outputs.rend(); ++i)
outputs = ATinsert(outputs,
makeDerivationOutput(
toATerm(i->first),
toATerm(i->second.path),
toATerm(i->second.hashAlgo),
toATerm(i->second.hash)));
ATermList inDrvs = ATempty;
for (DerivationInputs::const_reverse_iterator i = drv.inputDrvs.rbegin();
i != drv.inputDrvs.rend(); ++i)
inDrvs = ATinsert(inDrvs,
makeDerivationInput(
toATerm(i->first),
toATermList(i->second)));
ATermList args = ATempty;
for (Strings::const_reverse_iterator i = drv.args.rbegin();
i != drv.args.rend(); ++i)
args = ATinsert(args, toATerm(*i));
ATermList env = ATempty;
for (StringPairs::const_reverse_iterator i = drv.env.rbegin();
i != drv.env.rend(); ++i)
env = ATinsert(env,
makeEnvBinding(
toATerm(i->first),
toATerm(i->second)));
return makeDerive(
outputs,
inDrvs,
toATermList(drv.inputSrcs),
toATerm(drv.platform),
toATerm(drv.builder),
args,
env);
}
bool isDerivation(const string & fileName)
{
return
fileName.size() >= drvExtension.size() &&
string(fileName, fileName.size() - drvExtension.size()) == drvExtension;
}
}