lix/src/libstore/remote-store.cc
Eelco Dolstra ab2ef851b6
Merge pull request #4207 from hercules-ci/fix-RemoteStore-filterSource-deadlock
Fix RemoteStore pool deadlock in filterSource etc
2020-11-02 14:46:10 +01:00

950 lines
29 KiB
C++

#include "serialise.hh"
#include "util.hh"
#include "remote-fs-accessor.hh"
#include "remote-store.hh"
#include "worker-protocol.hh"
#include "archive.hh"
#include "affinity.hh"
#include "globals.hh"
#include "derivations.hh"
#include "pool.hh"
#include "finally.hh"
#include "logging.hh"
#include "callback.hh"
#include "filetransfer.hh"
namespace nix {
namespace worker_proto {
std::string read(const Store & store, Source & from, Phantom<std::string> _)
{
return readString(from);
}
void write(const Store & store, Sink & out, const std::string & str)
{
out << str;
}
StorePath read(const Store & store, Source & from, Phantom<StorePath> _)
{
return store.parseStorePath(readString(from));
}
void write(const Store & store, Sink & out, const StorePath & storePath)
{
out << store.printStorePath(storePath);
}
ContentAddress read(const Store & store, Source & from, Phantom<ContentAddress> _)
{
return parseContentAddress(readString(from));
}
void write(const Store & store, Sink & out, const ContentAddress & ca)
{
out << renderContentAddress(ca);
}
std::optional<StorePath> read(const Store & store, Source & from, Phantom<std::optional<StorePath>> _)
{
auto s = readString(from);
return s == "" ? std::optional<StorePath> {} : store.parseStorePath(s);
}
void write(const Store & store, Sink & out, const std::optional<StorePath> & storePathOpt)
{
out << (storePathOpt ? store.printStorePath(*storePathOpt) : "");
}
std::optional<ContentAddress> read(const Store & store, Source & from, Phantom<std::optional<ContentAddress>> _)
{
return parseContentAddressOpt(readString(from));
}
void write(const Store & store, Sink & out, const std::optional<ContentAddress> & caOpt)
{
out << (caOpt ? renderContentAddress(*caOpt) : "");
}
}
/* TODO: Separate these store impls into different files, give them better names */
RemoteStore::RemoteStore(const Params & params)
: Store(params)
, RemoteStoreConfig(params)
, connections(make_ref<Pool<Connection>>(
std::max(1, (int) maxConnections),
[this]() {
auto conn = openConnectionWrapper();
try {
initConnection(*conn);
} catch (...) {
failed = true;
throw;
}
return conn;
},
[this](const ref<Connection> & r) {
return
r->to.good()
&& r->from.good()
&& std::chrono::duration_cast<std::chrono::seconds>(
std::chrono::steady_clock::now() - r->startTime).count() < maxConnectionAge;
}
))
{
}
ref<RemoteStore::Connection> RemoteStore::openConnectionWrapper()
{
if (failed)
throw Error("opening a connection to remote store '%s' previously failed", getUri());
try {
return openConnection();
} catch (...) {
failed = true;
throw;
}
}
void RemoteStore::initConnection(Connection & conn)
{
/* Send the magic greeting, check for the reply. */
try {
conn.to << WORKER_MAGIC_1;
conn.to.flush();
unsigned int magic = readInt(conn.from);
if (magic != WORKER_MAGIC_2) throw Error("protocol mismatch");
conn.from >> conn.daemonVersion;
if (GET_PROTOCOL_MAJOR(conn.daemonVersion) != GET_PROTOCOL_MAJOR(PROTOCOL_VERSION))
throw Error("Nix daemon protocol version not supported");
if (GET_PROTOCOL_MINOR(conn.daemonVersion) < 10)
throw Error("the Nix daemon version is too old");
conn.to << PROTOCOL_VERSION;
if (GET_PROTOCOL_MINOR(conn.daemonVersion) >= 14) {
int cpu = sameMachine() && settings.lockCPU ? lockToCurrentCPU() : -1;
if (cpu != -1)
conn.to << 1 << cpu;
else
conn.to << 0;
}
if (GET_PROTOCOL_MINOR(conn.daemonVersion) >= 11)
conn.to << false;
auto ex = conn.processStderr();
if (ex) std::rethrow_exception(ex);
}
catch (Error & e) {
throw Error("cannot open connection to remote store '%s': %s", getUri(), e.what());
}
setOptions(conn);
}
void RemoteStore::setOptions(Connection & conn)
{
conn.to << wopSetOptions
<< settings.keepFailed
<< settings.keepGoing
<< settings.tryFallback
<< verbosity
<< settings.maxBuildJobs
<< settings.maxSilentTime
<< true
<< (settings.verboseBuild ? lvlError : lvlVomit)
<< 0 // obsolete log type
<< 0 /* obsolete print build trace */
<< settings.buildCores
<< settings.useSubstitutes;
if (GET_PROTOCOL_MINOR(conn.daemonVersion) >= 12) {
std::map<std::string, Config::SettingInfo> overrides;
settings.getSettings(overrides, true); // libstore settings
fileTransferSettings.getSettings(overrides, true);
overrides.erase(settings.keepFailed.name);
overrides.erase(settings.keepGoing.name);
overrides.erase(settings.tryFallback.name);
overrides.erase(settings.maxBuildJobs.name);
overrides.erase(settings.maxSilentTime.name);
overrides.erase(settings.buildCores.name);
overrides.erase(settings.useSubstitutes.name);
overrides.erase(loggerSettings.showTrace.name);
conn.to << overrides.size();
for (auto & i : overrides)
conn.to << i.first << i.second.value;
}
auto ex = conn.processStderr();
if (ex) std::rethrow_exception(ex);
}
/* A wrapper around Pool<RemoteStore::Connection>::Handle that marks
the connection as bad (causing it to be closed) if a non-daemon
exception is thrown before the handle is closed. Such an exception
causes a deviation from the expected protocol and therefore a
desynchronization between the client and daemon. */
struct ConnectionHandle
{
Pool<RemoteStore::Connection>::Handle handle;
bool daemonException = false;
ConnectionHandle(Pool<RemoteStore::Connection>::Handle && handle)
: handle(std::move(handle))
{ }
ConnectionHandle(ConnectionHandle && h)
: handle(std::move(h.handle))
{ }
~ConnectionHandle()
{
if (!daemonException && std::uncaught_exceptions()) {
handle.markBad();
debug("closing daemon connection because of an exception");
}
}
RemoteStore::Connection * operator -> () { return &*handle; }
void processStderr(Sink * sink = 0, Source * source = 0, bool flush = true)
{
auto ex = handle->processStderr(sink, source, flush);
if (ex) {
daemonException = true;
std::rethrow_exception(ex);
}
}
void withFramedSink(std::function<void(Sink & sink)> fun);
};
ConnectionHandle RemoteStore::getConnection()
{
return ConnectionHandle(connections->get());
}
bool RemoteStore::isValidPathUncached(const StorePath & path)
{
auto conn(getConnection());
conn->to << wopIsValidPath << printStorePath(path);
conn.processStderr();
return readInt(conn->from);
}
StorePathSet RemoteStore::queryValidPaths(const StorePathSet & paths, SubstituteFlag maybeSubstitute)
{
auto conn(getConnection());
if (GET_PROTOCOL_MINOR(conn->daemonVersion) < 12) {
StorePathSet res;
for (auto & i : paths)
if (isValidPath(i)) res.insert(i);
return res;
} else {
conn->to << wopQueryValidPaths;
worker_proto::write(*this, conn->to, paths);
conn.processStderr();
return worker_proto::read(*this, conn->from, Phantom<StorePathSet> {});
}
}
StorePathSet RemoteStore::queryAllValidPaths()
{
auto conn(getConnection());
conn->to << wopQueryAllValidPaths;
conn.processStderr();
return worker_proto::read(*this, conn->from, Phantom<StorePathSet> {});
}
StorePathSet RemoteStore::querySubstitutablePaths(const StorePathSet & paths)
{
auto conn(getConnection());
if (GET_PROTOCOL_MINOR(conn->daemonVersion) < 12) {
StorePathSet res;
for (auto & i : paths) {
conn->to << wopHasSubstitutes << printStorePath(i);
conn.processStderr();
if (readInt(conn->from)) res.insert(i);
}
return res;
} else {
conn->to << wopQuerySubstitutablePaths;
worker_proto::write(*this, conn->to, paths);
conn.processStderr();
return worker_proto::read(*this, conn->from, Phantom<StorePathSet> {});
}
}
void RemoteStore::querySubstitutablePathInfos(const StorePathCAMap & pathsMap, SubstitutablePathInfos & infos)
{
if (pathsMap.empty()) return;
auto conn(getConnection());
if (GET_PROTOCOL_MINOR(conn->daemonVersion) < 12) {
for (auto & i : pathsMap) {
SubstitutablePathInfo info;
conn->to << wopQuerySubstitutablePathInfo << printStorePath(i.first);
conn.processStderr();
unsigned int reply = readInt(conn->from);
if (reply == 0) continue;
auto deriver = readString(conn->from);
if (deriver != "")
info.deriver = parseStorePath(deriver);
info.references = worker_proto::read(*this, conn->from, Phantom<StorePathSet> {});
info.downloadSize = readLongLong(conn->from);
info.narSize = readLongLong(conn->from);
infos.insert_or_assign(i.first, std::move(info));
}
} else {
conn->to << wopQuerySubstitutablePathInfos;
if (GET_PROTOCOL_MINOR(conn->daemonVersion) < 22) {
StorePathSet paths;
for (auto & path : pathsMap)
paths.insert(path.first);
worker_proto::write(*this, conn->to, paths);
} else
worker_proto::write(*this, conn->to, pathsMap);
conn.processStderr();
size_t count = readNum<size_t>(conn->from);
for (size_t n = 0; n < count; n++) {
SubstitutablePathInfo & info(infos[parseStorePath(readString(conn->from))]);
auto deriver = readString(conn->from);
if (deriver != "")
info.deriver = parseStorePath(deriver);
info.references = worker_proto::read(*this, conn->from, Phantom<StorePathSet> {});
info.downloadSize = readLongLong(conn->from);
info.narSize = readLongLong(conn->from);
}
}
}
ref<const ValidPathInfo> RemoteStore::readValidPathInfo(ConnectionHandle & conn, const StorePath & path)
{
auto deriver = readString(conn->from);
auto narHash = Hash::parseAny(readString(conn->from), htSHA256);
auto info = make_ref<ValidPathInfo>(path, narHash);
if (deriver != "") info->deriver = parseStorePath(deriver);
info->references = worker_proto::read(*this, conn->from, Phantom<StorePathSet> {});
conn->from >> info->registrationTime >> info->narSize;
if (GET_PROTOCOL_MINOR(conn->daemonVersion) >= 16) {
conn->from >> info->ultimate;
info->sigs = readStrings<StringSet>(conn->from);
info->ca = parseContentAddressOpt(readString(conn->from));
}
return info;
}
void RemoteStore::queryPathInfoUncached(const StorePath & path,
Callback<std::shared_ptr<const ValidPathInfo>> callback) noexcept
{
try {
std::shared_ptr<const ValidPathInfo> info;
{
auto conn(getConnection());
conn->to << wopQueryPathInfo << printStorePath(path);
try {
conn.processStderr();
} catch (Error & e) {
// Ugly backwards compatibility hack.
if (e.msg().find("is not valid") != std::string::npos)
throw InvalidPath(e.info());
throw;
}
if (GET_PROTOCOL_MINOR(conn->daemonVersion) >= 17) {
bool valid; conn->from >> valid;
if (!valid) throw InvalidPath("path '%s' is not valid", printStorePath(path));
}
info = readValidPathInfo(conn, path);
}
callback(std::move(info));
} catch (...) { callback.rethrow(); }
}
void RemoteStore::queryReferrers(const StorePath & path,
StorePathSet & referrers)
{
auto conn(getConnection());
conn->to << wopQueryReferrers << printStorePath(path);
conn.processStderr();
for (auto & i : worker_proto::read(*this, conn->from, Phantom<StorePathSet> {}))
referrers.insert(i);
}
StorePathSet RemoteStore::queryValidDerivers(const StorePath & path)
{
auto conn(getConnection());
conn->to << wopQueryValidDerivers << printStorePath(path);
conn.processStderr();
return worker_proto::read(*this, conn->from, Phantom<StorePathSet> {});
}
StorePathSet RemoteStore::queryDerivationOutputs(const StorePath & path)
{
auto conn(getConnection());
if (GET_PROTOCOL_MINOR(conn->daemonVersion) >= 0x16) {
return Store::queryDerivationOutputs(path);
}
conn->to << wopQueryDerivationOutputs << printStorePath(path);
conn.processStderr();
return worker_proto::read(*this, conn->from, Phantom<StorePathSet> {});
}
std::map<std::string, std::optional<StorePath>> RemoteStore::queryPartialDerivationOutputMap(const StorePath & path)
{
if (GET_PROTOCOL_MINOR(getProtocol()) >= 0x16) {
auto conn(getConnection());
conn->to << wopQueryDerivationOutputMap << printStorePath(path);
conn.processStderr();
return worker_proto::read(*this, conn->from, Phantom<std::map<std::string, std::optional<StorePath>>> {});
} else {
// Fallback for old daemon versions.
// For floating-CA derivations (and their co-dependencies) this is an
// under-approximation as it only returns the paths that can be inferred
// from the derivation itself (and not the ones that are known because
// the have been built), but as old stores don't handle floating-CA
// derivations this shouldn't matter
auto derivation = readDerivation(path);
auto outputsWithOptPaths = derivation.outputsAndOptPaths(*this);
std::map<std::string, std::optional<StorePath>> ret;
for (auto & [outputName, outputAndPath] : outputsWithOptPaths) {
ret.emplace(outputName, outputAndPath.second);
}
return ret;
}
}
std::optional<StorePath> RemoteStore::queryPathFromHashPart(const std::string & hashPart)
{
auto conn(getConnection());
conn->to << wopQueryPathFromHashPart << hashPart;
conn.processStderr();
Path path = readString(conn->from);
if (path.empty()) return {};
return parseStorePath(path);
}
ref<const ValidPathInfo> RemoteStore::addCAToStore(
Source & dump,
const string & name,
ContentAddressMethod caMethod,
const StorePathSet & references,
RepairFlag repair)
{
std::optional<ConnectionHandle> conn_(getConnection());
auto & conn = *conn_;
if (GET_PROTOCOL_MINOR(conn->daemonVersion) >= 25) {
conn->to
<< wopAddToStore
<< name
<< renderContentAddressMethod(caMethod);
worker_proto::write(*this, conn->to, references);
conn->to << repair;
// The dump source may invoke the store, so we need to make some room.
connections->incCapacity();
{
Finally cleanup([&]() { connections->decCapacity(); });
conn.withFramedSink([&](Sink & sink) {
dump.drainInto(sink);
});
}
auto path = parseStorePath(readString(conn->from));
return readValidPathInfo(conn, path);
}
else {
if (repair) throw Error("repairing is not supported when building through the Nix daemon protocol < 1.25");
std::visit(overloaded {
[&](TextHashMethod thm) -> void {
std::string s = dump.drain();
conn->to << wopAddTextToStore << name << s;
worker_proto::write(*this, conn->to, references);
conn.processStderr();
},
[&](FixedOutputHashMethod fohm) -> void {
conn->to
<< wopAddToStore
<< name
<< ((fohm.hashType == htSHA256 && fohm.fileIngestionMethod == FileIngestionMethod::Recursive) ? 0 : 1) /* backwards compatibility hack */
<< (fohm.fileIngestionMethod == FileIngestionMethod::Recursive ? 1 : 0)
<< printHashType(fohm.hashType);
try {
conn->to.written = 0;
conn->to.warn = true;
connections->incCapacity();
{
Finally cleanup([&]() { connections->decCapacity(); });
if (fohm.fileIngestionMethod == FileIngestionMethod::Recursive) {
dump.drainInto(conn->to);
} else {
std::string contents = dump.drain();
dumpString(contents, conn->to);
}
}
conn->to.warn = false;
conn.processStderr();
} catch (SysError & e) {
/* Daemon closed while we were sending the path. Probably OOM
or I/O error. */
if (e.errNo == EPIPE)
try {
conn.processStderr();
} catch (EndOfFile & e) { }
throw;
}
}
}, caMethod);
auto path = parseStorePath(readString(conn->from));
// Release our connection to prevent a deadlock in queryPathInfo().
conn_.reset();
return queryPathInfo(path);
}
}
StorePath RemoteStore::addToStoreFromDump(Source & dump, const string & name,
FileIngestionMethod method, HashType hashType, RepairFlag repair)
{
StorePathSet references;
return addCAToStore(dump, name, FixedOutputHashMethod{ .fileIngestionMethod = method, .hashType = hashType }, references, repair)->path;
}
void RemoteStore::addToStore(const ValidPathInfo & info, Source & source,
RepairFlag repair, CheckSigsFlag checkSigs)
{
auto conn(getConnection());
if (GET_PROTOCOL_MINOR(conn->daemonVersion) < 18) {
conn->to << wopImportPaths;
auto source2 = sinkToSource([&](Sink & sink) {
sink << 1 // == path follows
;
copyNAR(source, sink);
sink
<< exportMagic
<< printStorePath(info.path);
worker_proto::write(*this, sink, info.references);
sink
<< (info.deriver ? printStorePath(*info.deriver) : "")
<< 0 // == no legacy signature
<< 0 // == no path follows
;
});
conn.processStderr(0, source2.get());
auto importedPaths = worker_proto::read(*this, conn->from, Phantom<StorePathSet> {});
assert(importedPaths.size() <= 1);
}
else {
conn->to << wopAddToStoreNar
<< printStorePath(info.path)
<< (info.deriver ? printStorePath(*info.deriver) : "")
<< info.narHash.to_string(Base16, false);
worker_proto::write(*this, conn->to, info.references);
conn->to << info.registrationTime << info.narSize
<< info.ultimate << info.sigs << renderContentAddress(info.ca)
<< repair << !checkSigs;
if (GET_PROTOCOL_MINOR(conn->daemonVersion) >= 23) {
conn.withFramedSink([&](Sink & sink) {
copyNAR(source, sink);
});
} else if (GET_PROTOCOL_MINOR(conn->daemonVersion) >= 21) {
conn.processStderr(0, &source);
} else {
copyNAR(source, conn->to);
conn.processStderr(0, nullptr);
}
}
}
StorePath RemoteStore::addTextToStore(const string & name, const string & s,
const StorePathSet & references, RepairFlag repair)
{
StringSource source(s);
return addCAToStore(source, name, TextHashMethod{}, references, repair)->path;
}
void RemoteStore::buildPaths(const std::vector<StorePathWithOutputs> & drvPaths, BuildMode buildMode)
{
auto conn(getConnection());
conn->to << wopBuildPaths;
assert(GET_PROTOCOL_MINOR(conn->daemonVersion) >= 13);
Strings ss;
for (auto & p : drvPaths)
ss.push_back(p.to_string(*this));
conn->to << ss;
if (GET_PROTOCOL_MINOR(conn->daemonVersion) >= 15)
conn->to << buildMode;
else
/* Old daemons did not take a 'buildMode' parameter, so we
need to validate it here on the client side. */
if (buildMode != bmNormal)
throw Error("repairing or checking is not supported when building through the Nix daemon");
conn.processStderr();
readInt(conn->from);
}
BuildResult RemoteStore::buildDerivation(const StorePath & drvPath, const BasicDerivation & drv,
BuildMode buildMode)
{
auto conn(getConnection());
conn->to << wopBuildDerivation << printStorePath(drvPath);
writeDerivation(conn->to, *this, drv);
conn->to << buildMode;
conn.processStderr();
BuildResult res;
unsigned int status;
conn->from >> status >> res.errorMsg;
res.status = (BuildResult::Status) status;
return res;
}
void RemoteStore::ensurePath(const StorePath & path)
{
auto conn(getConnection());
conn->to << wopEnsurePath << printStorePath(path);
conn.processStderr();
readInt(conn->from);
}
void RemoteStore::addTempRoot(const StorePath & path)
{
auto conn(getConnection());
conn->to << wopAddTempRoot << printStorePath(path);
conn.processStderr();
readInt(conn->from);
}
void RemoteStore::addIndirectRoot(const Path & path)
{
auto conn(getConnection());
conn->to << wopAddIndirectRoot << path;
conn.processStderr();
readInt(conn->from);
}
void RemoteStore::syncWithGC()
{
auto conn(getConnection());
conn->to << wopSyncWithGC;
conn.processStderr();
readInt(conn->from);
}
Roots RemoteStore::findRoots(bool censor)
{
auto conn(getConnection());
conn->to << wopFindRoots;
conn.processStderr();
size_t count = readNum<size_t>(conn->from);
Roots result;
while (count--) {
Path link = readString(conn->from);
auto target = parseStorePath(readString(conn->from));
result[std::move(target)].emplace(link);
}
return result;
}
void RemoteStore::collectGarbage(const GCOptions & options, GCResults & results)
{
auto conn(getConnection());
conn->to
<< wopCollectGarbage << options.action;
worker_proto::write(*this, conn->to, options.pathsToDelete);
conn->to << options.ignoreLiveness
<< options.maxFreed
/* removed options */
<< 0 << 0 << 0;
conn.processStderr();
results.paths = readStrings<PathSet>(conn->from);
results.bytesFreed = readLongLong(conn->from);
readLongLong(conn->from); // obsolete
{
auto state_(Store::state.lock());
state_->pathInfoCache.clear();
}
}
void RemoteStore::optimiseStore()
{
auto conn(getConnection());
conn->to << wopOptimiseStore;
conn.processStderr();
readInt(conn->from);
}
bool RemoteStore::verifyStore(bool checkContents, RepairFlag repair)
{
auto conn(getConnection());
conn->to << wopVerifyStore << checkContents << repair;
conn.processStderr();
return readInt(conn->from);
}
void RemoteStore::addSignatures(const StorePath & storePath, const StringSet & sigs)
{
auto conn(getConnection());
conn->to << wopAddSignatures << printStorePath(storePath) << sigs;
conn.processStderr();
readInt(conn->from);
}
void RemoteStore::queryMissing(const std::vector<StorePathWithOutputs> & targets,
StorePathSet & willBuild, StorePathSet & willSubstitute, StorePathSet & unknown,
uint64_t & downloadSize, uint64_t & narSize)
{
{
auto conn(getConnection());
if (GET_PROTOCOL_MINOR(conn->daemonVersion) < 19)
// Don't hold the connection handle in the fallback case
// to prevent a deadlock.
goto fallback;
conn->to << wopQueryMissing;
Strings ss;
for (auto & p : targets)
ss.push_back(p.to_string(*this));
conn->to << ss;
conn.processStderr();
willBuild = worker_proto::read(*this, conn->from, Phantom<StorePathSet> {});
willSubstitute = worker_proto::read(*this, conn->from, Phantom<StorePathSet> {});
unknown = worker_proto::read(*this, conn->from, Phantom<StorePathSet> {});
conn->from >> downloadSize >> narSize;
return;
}
fallback:
return Store::queryMissing(targets, willBuild, willSubstitute,
unknown, downloadSize, narSize);
}
void RemoteStore::connect()
{
auto conn(getConnection());
}
unsigned int RemoteStore::getProtocol()
{
auto conn(connections->get());
return conn->daemonVersion;
}
void RemoteStore::flushBadConnections()
{
connections->flushBad();
}
RemoteStore::Connection::~Connection()
{
try {
to.flush();
} catch (...) {
ignoreException();
}
}
void RemoteStore::narFromPath(const StorePath & path, Sink & sink)
{
auto conn(connections->get());
conn->to << wopNarFromPath << printStorePath(path);
conn->processStderr();
copyNAR(conn->from, sink);
}
ref<FSAccessor> RemoteStore::getFSAccessor()
{
return make_ref<RemoteFSAccessor>(ref<Store>(shared_from_this()));
}
static Logger::Fields readFields(Source & from)
{
Logger::Fields fields;
size_t size = readInt(from);
for (size_t n = 0; n < size; n++) {
auto type = (decltype(Logger::Field::type)) readInt(from);
if (type == Logger::Field::tInt)
fields.push_back(readNum<uint64_t>(from));
else if (type == Logger::Field::tString)
fields.push_back(readString(from));
else
throw Error("got unsupported field type %x from Nix daemon", (int) type);
}
return fields;
}
std::exception_ptr RemoteStore::Connection::processStderr(Sink * sink, Source * source, bool flush)
{
if (flush)
to.flush();
while (true) {
auto msg = readNum<uint64_t>(from);
if (msg == STDERR_WRITE) {
string s = readString(from);
if (!sink) throw Error("no sink");
(*sink)(s);
}
else if (msg == STDERR_READ) {
if (!source) throw Error("no source");
size_t len = readNum<size_t>(from);
auto buf = std::make_unique<unsigned char[]>(len);
writeString(buf.get(), source->read(buf.get(), len), to);
to.flush();
}
else if (msg == STDERR_ERROR) {
if (GET_PROTOCOL_MINOR(daemonVersion) >= 26) {
return std::make_exception_ptr(readError(from));
} else {
string error = readString(from);
unsigned int status = readInt(from);
return std::make_exception_ptr(Error(status, error));
}
}
else if (msg == STDERR_NEXT)
printError(chomp(readString(from)));
else if (msg == STDERR_START_ACTIVITY) {
auto act = readNum<ActivityId>(from);
auto lvl = (Verbosity) readInt(from);
auto type = (ActivityType) readInt(from);
auto s = readString(from);
auto fields = readFields(from);
auto parent = readNum<ActivityId>(from);
logger->startActivity(act, lvl, type, s, fields, parent);
}
else if (msg == STDERR_STOP_ACTIVITY) {
auto act = readNum<ActivityId>(from);
logger->stopActivity(act);
}
else if (msg == STDERR_RESULT) {
auto act = readNum<ActivityId>(from);
auto type = (ResultType) readInt(from);
auto fields = readFields(from);
logger->result(act, type, fields);
}
else if (msg == STDERR_LAST)
break;
else
throw Error("got unknown message type %x from Nix daemon", msg);
}
return nullptr;
}
void ConnectionHandle::withFramedSink(std::function<void(Sink &sink)> fun)
{
(*this)->to.flush();
std::exception_ptr ex;
/* Handle log messages / exceptions from the remote on a
separate thread. */
std::thread stderrThread([&]()
{
try {
processStderr(nullptr, nullptr, false);
} catch (...) {
ex = std::current_exception();
}
});
Finally joinStderrThread([&]()
{
if (stderrThread.joinable()) {
stderrThread.join();
if (ex) {
try {
std::rethrow_exception(ex);
} catch (...) {
ignoreException();
}
}
}
});
{
FramedSink sink((*this)->to, ex);
fun(sink);
sink.flush();
}
stderrThread.join();
if (ex)
std::rethrow_exception(ex);
}
}