diff options
Diffstat (limited to 'nix/libstore/misc.cc')
| -rw-r--r-- | nix/libstore/misc.cc | 220 |
1 files changed, 220 insertions, 0 deletions
diff --git a/nix/libstore/misc.cc b/nix/libstore/misc.cc new file mode 100644 index 0000000000..1bf3f93782 --- /dev/null +++ b/nix/libstore/misc.cc @@ -0,0 +1,220 @@ +#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 & path, + PathSet & paths, bool flipDirection, bool includeOutputs, bool includeDerivers) +{ + if (paths.find(path) != paths.end()) return; + paths.insert(path); + + PathSet edges; + + if (flipDirection) { + store.queryReferrers(path, edges); + + if (includeOutputs) { + PathSet derivers = store.queryValidDerivers(path); + foreach (PathSet::iterator, i, derivers) + edges.insert(*i); + } + + if (includeDerivers && isDerivation(path)) { + PathSet outputs = store.queryDerivationOutputs(path); + foreach (PathSet::iterator, i, outputs) + if (store.isValidPath(*i) && store.queryDeriver(*i) == path) + edges.insert(*i); + } + + } else { + store.queryReferences(path, edges); + + if (includeOutputs && isDerivation(path)) { + PathSet outputs = store.queryDerivationOutputs(path); + foreach (PathSet::iterator, i, outputs) + if (store.isValidPath(*i)) edges.insert(*i); + } + + if (includeDerivers) { + Path deriver = store.queryDeriver(path); + if (store.isValidPath(deriver)) edges.insert(deriver); + } + } + + foreach (PathSet::iterator, i, edges) + computeFSClosure(store, *i, paths, flipDirection, includeOutputs, includeDerivers); +} + + +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; + + /* Getting substitute info has high latency when using the binary + cache substituter. Thus it's essential to do substitute + queries in parallel as much as possible. To accomplish this + we do the following: + + - For all paths still to be processed (‘todo’), we add all + paths for which we need info to the set ‘query’. For an + unbuilt derivation this is the output paths; otherwise, it's + the path itself. + + - We get info about all paths in ‘query’ in parallel. + + - We process the results and add new items to ‘todo’ if + necessary. E.g. if a path is substitutable, then we need to + get info on its references. + + - Repeat until ‘todo’ is empty. + */ + + while (!todo.empty()) { + + PathSet query, todoDrv, todoNonDrv; + + foreach (PathSet::iterator, i, todo) { + if (done.find(*i) != done.end()) continue; + done.insert(*i); + + DrvPathWithOutputs i2 = parseDrvPathWithOutputs(*i); + + if (isDerivation(i2.first)) { + if (!store.isValidPath(i2.first)) { + // FIXME: we could try to substitute p. + unknown.insert(*i); + continue; + } + Derivation drv = derivationFromPath(store, i2.first); + + PathSet invalid; + foreach (DerivationOutputs::iterator, j, drv.outputs) + if (wantOutput(j->first, i2.second) + && !store.isValidPath(j->second.path)) + invalid.insert(j->second.path); + if (invalid.empty()) continue; + + todoDrv.insert(*i); + if (settings.useSubstitutes && !willBuildLocally(drv)) + query.insert(invalid.begin(), invalid.end()); + } + + else { + if (store.isValidPath(*i)) continue; + query.insert(*i); + todoNonDrv.insert(*i); + } + } + + todo.clear(); + + SubstitutablePathInfos infos; + store.querySubstitutablePathInfos(query, infos); + + foreach (PathSet::iterator, i, todoDrv) { + DrvPathWithOutputs i2 = parseDrvPathWithOutputs(*i); + + // FIXME: cache this + Derivation drv = derivationFromPath(store, i2.first); + + PathSet outputs; + bool mustBuild = false; + if (settings.useSubstitutes && !willBuildLocally(drv)) { + foreach (DerivationOutputs::iterator, j, drv.outputs) { + if (!wantOutput(j->first, i2.second)) continue; + if (!store.isValidPath(j->second.path)) { + if (infos.find(j->second.path) == infos.end()) + mustBuild = true; + else + outputs.insert(j->second.path); + } + } + } else + mustBuild = true; + + if (mustBuild) { + willBuild.insert(i2.first); + todo.insert(drv.inputSrcs.begin(), drv.inputSrcs.end()); + foreach (DerivationInputs::iterator, j, drv.inputDrvs) + todo.insert(makeDrvPathWithOutputs(j->first, j->second)); + } else + todoNonDrv.insert(outputs.begin(), outputs.end()); + } + + foreach (PathSet::iterator, i, todoNonDrv) { + done.insert(*i); + SubstitutablePathInfos::iterator info = infos.find(*i); + if (info != infos.end()) { + willSubstitute.insert(*i); + downloadSize += info->second.downloadSize; + narSize += info->second.narSize; + todo.insert(info->second.references.begin(), info->second.references.end()); + } else + unknown.insert(*i); + } + } +} + + +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; +} + + +} |