NixOS/nix
NixOS/nix
1
0
Fork 0
mirror of https://github.com/NixOS/nix synced 2024-09-21 11:30:30 -04:00
Code Activity
nix/src/libstore/remote-store.cc
Eelco Dolstra bbe97dff8b Make the Store API more type-safe 
Most functions now take a StorePath argument rather than a Path (which
is just an alias for std::string). The StorePath constructor ensures
that the path is syntactically correct (i.e. it looks like
<store-dir>/<base32-hash>-<name>). Similarly, functions like
buildPaths() now take a StorePathWithOutputs, rather than abusing Path
by adding a '!<outputs>' suffix.

Note that the StorePath type is implemented in Rust. This involves
some hackery to allow Rust values to be used directly in C++, via a
helper type whose destructor calls the Rust type's drop()
function. The main issue is the dynamic nature of C++ move semantics:
after we have moved a Rust value, we should not call the drop function
on the original value. So when we move a value, we set the original
value to bitwise zero, and the destructor only calls drop() if the
value is not bitwise zero. This should be sufficient for most types.

Also lots of minor cleanups to the C++ API to make it more modern
(e.g. using std::optional and std::string_view in some places).
2019-12-10 22:06:05 +01:00

828 lines
24 KiB
C++
Raw Blame History

#include "serialise.hh"
#include "util.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 <sys/types.h>
#include <sys/stat.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <errno.h>
#include <fcntl.h>
#include <unistd.h>
#include <cstring>
namespace nix {
template<> StorePathSet readStorePaths(const Store & store, Source & from)
{
StorePathSet paths;
for (auto & i : readStrings<Strings>(from))
paths.insert(store.parseStorePath(i));
return paths;
}
void writeStorePaths(const Store & store, Sink & out, const StorePathSet & paths)
{
out << paths.size();
for (auto & i : paths)
out << store.printStorePath(i);
}
/* TODO: Separate these store impls into different files, give them better names */
RemoteStore::RemoteStore(const Params & params)
: Store(params)
, connections(make_ref<Pool<Connection>>(
std::max(1, (int) maxConnections),
[this]() { return openConnectionWrapper(); },
[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;
}
}
UDSRemoteStore::UDSRemoteStore(const Params & params)
: Store(params)
, LocalFSStore(params)
, RemoteStore(params)
{
}
UDSRemoteStore::UDSRemoteStore(std::string socket_path, const Params & params)
: Store(params)
, LocalFSStore(params)
, RemoteStore(params)
, path(socket_path)
{
}
std::string UDSRemoteStore::getUri()
{
if (path) {
return std::string("unix://") + *path;
} else {
return "daemon";
}
}
ref<RemoteStore::Connection> UDSRemoteStore::openConnection()
{
auto conn = make_ref<Connection>();
/* Connect to a daemon that does the privileged work for us. */
conn->fd = socket(PF_UNIX, SOCK_STREAM
#ifdef SOCK_CLOEXEC
| SOCK_CLOEXEC
#endif
, 0);
if (!conn->fd)
throw SysError("cannot create Unix domain socket");
closeOnExec(conn->fd.get());
string socketPath = path ? *path : settings.nixDaemonSocketFile;
struct sockaddr_un addr;
addr.sun_family = AF_UNIX;
if (socketPath.size() + 1 >= sizeof(addr.sun_path))
throw Error(format("socket path '%1%' is too long") % socketPath);
strcpy(addr.sun_path, socketPath.c_str());
if (::connect(conn->fd.get(), (struct sockaddr *) &addr, sizeof(addr)) == -1)
throw SysError(format("cannot connect to daemon at '%1%'") % socketPath);
conn->from.fd = conn->fd.get();
conn->to.fd = conn->fd.get();
conn->startTime = std::chrono::steady_clock::now();
initConnection(*conn);
return conn;
}
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;
globalConfig.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(settings.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_exception()) {
handle.markBad();
debug("closing daemon connection because of an exception");
}
}
RemoteStore::Connection * operator -> () { return &*handle; }
void processStderr(Sink * sink = 0, Source * source = 0)
{
auto ex = handle->processStderr(sink, source);
if (ex) {
daemonException = true;
std::rethrow_exception(ex);
}
}
};
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.clone());
return res;
} else {
conn->to << wopQueryValidPaths;
writeStorePaths(*this, conn->to, paths);
conn.processStderr();
return readStorePaths<StorePathSet>(*this, conn->from);
}
}
StorePathSet RemoteStore::queryAllValidPaths()
{
auto conn(getConnection());
conn->to << wopQueryAllValidPaths;
conn.processStderr();
return readStorePaths<StorePathSet>(*this, conn->from);
}
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.clone());
}
return res;
} else {
conn->to << wopQuerySubstitutablePaths;
writeStorePaths(*this, conn->to, paths);
conn.processStderr();
return readStorePaths<StorePathSet>(*this, conn->from);
}
}
void RemoteStore::querySubstitutablePathInfos(const StorePathSet & paths,
SubstitutablePathInfos & infos)
{
if (paths.empty()) return;
auto conn(getConnection());
if (GET_PROTOCOL_MINOR(conn->daemonVersion) < 12) {
for (auto & i : paths) {
SubstitutablePathInfo info;
conn->to << wopQuerySubstitutablePathInfo << printStorePath(i);
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 = readStorePaths<StorePathSet>(*this, conn->from);
info.downloadSize = readLongLong(conn->from);
info.narSize = readLongLong(conn->from);
infos.insert_or_assign(i.clone(), std::move(info));
}
} else {
conn->to << wopQuerySubstitutablePathInfos;
writeStorePaths(*this, conn->to, paths);
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 = readStorePaths<StorePathSet>(*this, conn->from);
info.downloadSize = readLongLong(conn->from);
info.narSize = readLongLong(conn->from);
}
}
}
void RemoteStore::queryPathInfoUncached(const StorePath & path,
Callback<std::shared_ptr<const ValidPathInfo>> callback) noexcept
{
try {
std::shared_ptr<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.what());
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 = std::make_shared<ValidPathInfo>(path.clone());
auto deriver = readString(conn->from);
if (deriver != "") info->deriver = parseStorePath(deriver);
info->narHash = Hash(readString(conn->from), htSHA256);
info->references = readStorePaths<StorePathSet>(*this, conn->from);
conn->from >> info->registrationTime >> info->narSize;
if (GET_PROTOCOL_MINOR(conn->daemonVersion) >= 16) {
conn->from >> info->ultimate;
info->sigs = readStrings<StringSet>(conn->from);
conn->from >> info->ca;
}
}
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 : readStorePaths<StorePathSet>(*this, conn->from))
referrers.insert(i.clone());
}
StorePathSet RemoteStore::queryValidDerivers(const StorePath & path)
{
auto conn(getConnection());
conn->to << wopQueryValidDerivers << printStorePath(path);
conn.processStderr();
return readStorePaths<StorePathSet>(*this, conn->from);
}
StorePathSet RemoteStore::queryDerivationOutputs(const StorePath & path)
{
auto conn(getConnection());
conn->to << wopQueryDerivationOutputs << printStorePath(path);
conn.processStderr();
return readStorePaths<StorePathSet>(*this, conn->from);
}
PathSet RemoteStore::queryDerivationOutputNames(const StorePath & path)
{
auto conn(getConnection());
conn->to << wopQueryDerivationOutputNames << printStorePath(path);
conn.processStderr();
return readStrings<PathSet>(conn->from);
}
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);
}
void RemoteStore::addToStore(const ValidPathInfo & info, Source & source,
RepairFlag repair, CheckSigsFlag checkSigs, std::shared_ptr<FSAccessor> accessor)
{
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);
writeStorePaths(*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 = readStorePaths<StorePathSet>(*this, conn->from);
assert(importedPaths.size() <= 1);
}
else {
conn->to << wopAddToStoreNar
<< printStorePath(info.path)
<< (info.deriver ? printStorePath(*info.deriver) : "")
<< info.narHash.to_string(Base16, false);
writeStorePaths(*this, conn->to, info.references);
conn->to << info.registrationTime << info.narSize
<< info.ultimate << info.sigs << info.ca
<< repair << !checkSigs;
bool tunnel = GET_PROTOCOL_MINOR(conn->daemonVersion) >= 21;
if (!tunnel) copyNAR(source, conn->to);
conn.processStderr(0, tunnel ? &source : nullptr);
}
}
StorePath RemoteStore::addToStore(const string & name, const Path & _srcPath,
bool recursive, HashType hashAlgo, PathFilter & filter, RepairFlag repair)
{
if (repair) throw Error("repairing is not supported when building through the Nix daemon");
auto conn(getConnection());
Path srcPath(absPath(_srcPath));
conn->to << wopAddToStore << name
<< ((hashAlgo == htSHA256 && recursive) ? 0 : 1) /* backwards compatibility hack */
<< (recursive ? 1 : 0)
<< printHashType(hashAlgo);
try {
conn->to.written = 0;
conn->to.warn = true;
connections->incCapacity();
{
Finally cleanup([&]() { connections->decCapacity(); });
dumpPath(srcPath, conn->to, filter);
}
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;
}
return parseStorePath(readString(conn->from));
}
StorePath RemoteStore::addTextToStore(const string & name, const string & s,
const StorePathSet & references, RepairFlag repair)
{
if (repair) throw Error("repairing is not supported when building through the Nix daemon");
auto conn(getConnection());
conn->to << wopAddTextToStore << name << s;
writeStorePaths(*this, conn->to, references);
conn.processStderr();
return parseStorePath(readString(conn->from));
}
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;
writeStorePaths(*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,
unsigned long long & downloadSize, unsigned long long & 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 = readStorePaths<StorePathSet>(*this, conn->from);
willSubstitute = readStorePaths<StorePathSet>(*this, conn->from);
unknown = readStorePaths<StorePathSet>(*this, conn->from);
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();
}
}
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)
{
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) {
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;
}
static std::string uriScheme = "unix://";
static RegisterStoreImplementation regStore([](
const std::string & uri, const Store::Params & params)
-> std::shared_ptr<Store>
{
if (std::string(uri, 0, uriScheme.size()) != uriScheme) return 0;
return std::make_shared<UDSRemoteStore>(std::string(uri, uriScheme.size()), params);
});
}
View git blame Copy permalink