tvl-depot/src/libstore/misc.cc
Eelco Dolstra db5b86ef13 * Add an option ‘build-use-substitutes’, which can be set to ‘false’
to disable use of substitutes; i.e., force building from source.
  Fixes Nix/221.
2012-04-30 19:15:34 -04:00

138 lines
4.2 KiB
C++

#include "misc.hh"
#include "store-api.hh"
#include "local-store.hh"
#include "globals.hh"
namespace nix {
Derivation derivationFromPath(StoreAPI & store, const Path & drvPath)
{
assertStorePath(drvPath);
store.ensurePath(drvPath);
return parseDerivation(readFile(drvPath));
}
void computeFSClosure(StoreAPI & store, const Path & storePath,
PathSet & paths, bool flipDirection, bool includeOutputs)
{
if (paths.find(storePath) != paths.end()) return;
paths.insert(storePath);
PathSet references;
if (flipDirection)
store.queryReferrers(storePath, references);
else
store.queryReferences(storePath, references);
if (includeOutputs && isDerivation(storePath)) {
PathSet outputs = store.queryDerivationOutputs(storePath);
foreach (PathSet::iterator, i, outputs)
if (store.isValidPath(*i))
computeFSClosure(store, *i, paths, flipDirection, true);
}
foreach (PathSet::iterator, i, references)
computeFSClosure(store, *i, paths, flipDirection, includeOutputs);
}
Path findOutput(const Derivation & drv, string id)
{
foreach (DerivationOutputs::const_iterator, i, drv.outputs)
if (i->first == id) return i->second.path;
throw Error(format("derivation has no output `%1%'") % id);
}
void queryMissing(StoreAPI & store, const PathSet & targets,
PathSet & willBuild, PathSet & willSubstitute, PathSet & unknown,
unsigned long long & downloadSize, unsigned long long & narSize)
{
downloadSize = narSize = 0;
PathSet todo(targets.begin(), targets.end()), done;
while (!todo.empty()) {
Path p = *(todo.begin());
todo.erase(p);
if (done.find(p) != done.end()) continue;
done.insert(p);
if (isDerivation(p)) {
if (!store.isValidPath(p)) {
unknown.insert(p);
continue;
}
Derivation drv = derivationFromPath(store, p);
bool mustBuild = false;
foreach (DerivationOutputs::iterator, i, drv.outputs)
if (!store.isValidPath(i->second.path) &&
!(queryBoolSetting("build-use-substitutes", true) && store.hasSubstitutes(i->second.path)))
mustBuild = true;
if (mustBuild) {
willBuild.insert(p);
todo.insert(drv.inputSrcs.begin(), drv.inputSrcs.end());
foreach (DerivationInputs::iterator, i, drv.inputDrvs)
todo.insert(i->first);
} else
foreach (DerivationOutputs::iterator, i, drv.outputs)
todo.insert(i->second.path);
}
else {
if (store.isValidPath(p)) continue;
SubstitutablePathInfo info;
if (store.querySubstitutablePathInfo(p, info)) {
willSubstitute.insert(p);
downloadSize += info.downloadSize;
narSize += info.narSize;
todo.insert(info.references.begin(), info.references.end());
} else
unknown.insert(p);
}
}
}
static void dfsVisit(StoreAPI & store, const PathSet & paths,
const Path & path, PathSet & visited, Paths & sorted,
PathSet & parents)
{
if (parents.find(path) != parents.end())
throw BuildError(format("cycle detected in the references of `%1%'") % path);
if (visited.find(path) != visited.end()) return;
visited.insert(path);
parents.insert(path);
PathSet references;
if (store.isValidPath(path))
store.queryReferences(path, references);
foreach (PathSet::iterator, i, references)
/* Don't traverse into paths that don't exist. That can
happen due to substitutes for non-existent paths. */
if (*i != path && paths.find(*i) != paths.end())
dfsVisit(store, paths, *i, visited, sorted, parents);
sorted.push_front(path);
parents.erase(path);
}
Paths topoSortPaths(StoreAPI & store, const PathSet & paths)
{
Paths sorted;
PathSet visited, parents;
foreach (PathSet::const_iterator, i, paths)
dfsVisit(store, paths, *i, visited, sorted, parents);
return sorted;
}
}