lix/src/libstore/build/substitution-goal.cc
2021-07-22 09:59:51 +02:00

303 lines
8.3 KiB
C++

#include "worker.hh"
#include "substitution-goal.hh"
#include "nar-info.hh"
#include "finally.hh"
namespace nix {
PathSubstitutionGoal::PathSubstitutionGoal(const StorePath & storePath, Worker & worker, RepairFlag repair, std::optional<ContentAddress> ca)
: Goal(worker)
, storePath(storePath)
, repair(repair)
, ca(ca)
{
state = &PathSubstitutionGoal::init;
name = fmt("substitution of '%s'", worker.store.printStorePath(this->storePath));
trace("created");
maintainExpectedSubstitutions = std::make_unique<MaintainCount<uint64_t>>(worker.expectedSubstitutions);
}
PathSubstitutionGoal::~PathSubstitutionGoal()
{
cleanup();
}
void PathSubstitutionGoal::work()
{
(this->*state)();
}
void PathSubstitutionGoal::init()
{
trace("init");
worker.store.addTempRoot(storePath);
/* If the path already exists we're done. */
if (!repair && worker.store.isValidPath(storePath)) {
amDone(ecSuccess);
return;
}
if (settings.readOnlyMode)
throw Error("cannot substitute path '%s' - no write access to the Nix store", worker.store.printStorePath(storePath));
subs = settings.useSubstitutes ? getDefaultSubstituters() : std::list<ref<Store>>();
tryNext();
}
void PathSubstitutionGoal::tryNext()
{
trace("trying next substituter");
cleanup();
if (subs.size() == 0) {
/* None left. Terminate this goal and let someone else deal
with it. */
debug("path '%s' is required, but there is no substituter that can build it", worker.store.printStorePath(storePath));
/* Hack: don't indicate failure if there were no substituters.
In that case the calling derivation should just do a
build. */
amDone(substituterFailed ? ecFailed : ecNoSubstituters);
if (substituterFailed) {
worker.failedSubstitutions++;
worker.updateProgress();
}
return;
}
sub = subs.front();
subs.pop_front();
if (ca) {
subPath = sub->makeFixedOutputPathFromCA(storePath.name(), *ca);
if (sub->storeDir == worker.store.storeDir)
assert(subPath == storePath);
} else if (sub->storeDir != worker.store.storeDir) {
tryNext();
return;
}
try {
// FIXME: make async
info = sub->queryPathInfo(subPath ? *subPath : storePath);
} catch (InvalidPath &) {
tryNext();
return;
} catch (SubstituterDisabled &) {
if (settings.tryFallback) {
tryNext();
return;
}
throw;
} catch (Error & e) {
if (settings.tryFallback) {
logError(e.info());
tryNext();
return;
}
throw;
}
if (info->path != storePath) {
if (info->isContentAddressed(*sub) && info->references.empty()) {
auto info2 = std::make_shared<ValidPathInfo>(*info);
info2->path = storePath;
info = info2;
} else {
printError("asked '%s' for '%s' but got '%s'",
sub->getUri(), worker.store.printStorePath(storePath), sub->printStorePath(info->path));
tryNext();
return;
}
}
/* Update the total expected download size. */
auto narInfo = std::dynamic_pointer_cast<const NarInfo>(info);
maintainExpectedNar = std::make_unique<MaintainCount<uint64_t>>(worker.expectedNarSize, info->narSize);
maintainExpectedDownload =
narInfo && narInfo->fileSize
? std::make_unique<MaintainCount<uint64_t>>(worker.expectedDownloadSize, narInfo->fileSize)
: nullptr;
worker.updateProgress();
/* Bail out early if this substituter lacks a valid
signature. LocalStore::addToStore() also checks for this, but
only after we've downloaded the path. */
if (!sub->isTrusted && worker.store.pathInfoIsUntrusted(*info))
{
warn("substituter '%s' does not have a valid signature for path '%s'",
sub->getUri(), worker.store.printStorePath(storePath));
tryNext();
return;
}
/* To maintain the closure invariant, we first have to realise the
paths referenced by this one. */
for (auto & i : info->references)
if (i != storePath) /* ignore self-references */
addWaitee(worker.makePathSubstitutionGoal(i));
if (waitees.empty()) /* to prevent hang (no wake-up event) */
referencesValid();
else
state = &PathSubstitutionGoal::referencesValid;
}
void PathSubstitutionGoal::referencesValid()
{
trace("all references realised");
if (nrFailed > 0) {
debug("some references of path '%s' could not be realised", worker.store.printStorePath(storePath));
amDone(nrNoSubstituters > 0 || nrIncompleteClosure > 0 ? ecIncompleteClosure : ecFailed);
return;
}
for (auto & i : info->references)
if (i != storePath) /* ignore self-references */
assert(worker.store.isValidPath(i));
state = &PathSubstitutionGoal::tryToRun;
worker.wakeUp(shared_from_this());
}
void PathSubstitutionGoal::tryToRun()
{
trace("trying to run");
/* Make sure that we are allowed to start a build. Note that even
if maxBuildJobs == 0 (no local builds allowed), we still allow
a substituter to run. This is because substitutions cannot be
distributed to another machine via the build hook. */
if (worker.getNrLocalBuilds() >= std::max(1U, (unsigned int) settings.maxBuildJobs)) {
worker.waitForBuildSlot(shared_from_this());
return;
}
maintainRunningSubstitutions = std::make_unique<MaintainCount<uint64_t>>(worker.runningSubstitutions);
worker.updateProgress();
outPipe.create();
promise = std::promise<void>();
thr = std::thread([this]() {
try {
/* Wake up the worker loop when we're done. */
Finally updateStats([this]() { outPipe.writeSide.close(); });
Activity act(*logger, actSubstitute, Logger::Fields{worker.store.printStorePath(storePath), sub->getUri()});
PushActivity pact(act.id);
copyStorePath(*sub, worker.store,
subPath ? *subPath : storePath, repair, sub->isTrusted ? NoCheckSigs : CheckSigs);
promise.set_value();
} catch (...) {
promise.set_exception(std::current_exception());
}
});
worker.childStarted(shared_from_this(), {outPipe.readSide.get()}, true, false);
state = &PathSubstitutionGoal::finished;
}
void PathSubstitutionGoal::finished()
{
trace("substitute finished");
thr.join();
worker.childTerminated(this);
try {
promise.get_future().get();
} catch (std::exception & e) {
printError(e.what());
/* Cause the parent build to fail unless --fallback is given,
or the substitute has disappeared. The latter case behaves
the same as the substitute never having existed in the
first place. */
try {
throw;
} catch (SubstituteGone &) {
} catch (...) {
substituterFailed = true;
}
/* Try the next substitute. */
state = &PathSubstitutionGoal::tryNext;
worker.wakeUp(shared_from_this());
return;
}
worker.markContentsGood(storePath);
printMsg(lvlChatty, "substitution of path '%s' succeeded", worker.store.printStorePath(storePath));
maintainRunningSubstitutions.reset();
maintainExpectedSubstitutions.reset();
worker.doneSubstitutions++;
if (maintainExpectedDownload) {
auto fileSize = maintainExpectedDownload->delta;
maintainExpectedDownload.reset();
worker.doneDownloadSize += fileSize;
}
worker.doneNarSize += maintainExpectedNar->delta;
maintainExpectedNar.reset();
worker.updateProgress();
amDone(ecSuccess);
}
void PathSubstitutionGoal::handleChildOutput(int fd, const string & data)
{
}
void PathSubstitutionGoal::handleEOF(int fd)
{
if (fd == outPipe.readSide.get()) worker.wakeUp(shared_from_this());
}
void PathSubstitutionGoal::cleanup()
{
try {
if (thr.joinable()) {
// FIXME: signal worker thread to quit.
thr.join();
worker.childTerminated(this);
}
outPipe.close();
} catch (...) {
ignoreException();
}
}
}