lix/src/libstore/remote-store.cc
Eelco Dolstra 8be1979f1a Remove the --max-links GC option
We don't need this anymore now that current filesystems support more
than 32,000 files in a directory.
2012-03-26 20:00:02 +02:00

538 lines
13 KiB
C++

#include "serialise.hh"
#include "util.hh"
#include "remote-store.hh"
#include "worker-protocol.hh"
#include "archive.hh"
#include "globals.hh"
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <fcntl.h>
#include <iostream>
#include <unistd.h>
#include <cstring>
namespace nix {
Path readStorePath(Source & from)
{
Path path = readString(from);
assertStorePath(path);
return path;
}
template<class T> T readStorePaths(Source & from)
{
T paths = readStrings<T>(from);
foreach (typename T::iterator, i, paths) assertStorePath(*i);
return paths;
}
template PathSet readStorePaths(Source & from);
RemoteStore::RemoteStore()
{
initialised = false;
}
void RemoteStore::openConnection()
{
if (initialised) return;
initialised = true;
string remoteMode = getEnv("NIX_REMOTE");
if (remoteMode == "slave")
/* Fork off a setuid worker to do the privileged work. */
forkSlave();
else if (remoteMode == "daemon")
/* Connect to a daemon that does the privileged work for
us. */
connectToDaemon();
else
throw Error(format("invalid setting for NIX_REMOTE, `%1%'")
% remoteMode);
from.fd = fdSocket;
to.fd = fdSocket;
/* Send the magic greeting, check for the reply. */
try {
writeInt(WORKER_MAGIC_1, to);
to.flush();
unsigned int magic = readInt(from);
if (magic != WORKER_MAGIC_2) throw Error("protocol mismatch");
daemonVersion = readInt(from);
if (GET_PROTOCOL_MAJOR(daemonVersion) != GET_PROTOCOL_MAJOR(PROTOCOL_VERSION))
throw Error("Nix daemon protocol version not supported");
writeInt(PROTOCOL_VERSION, to);
processStderr();
}
catch (Error & e) {
throw Error(format("cannot start worker (%1%)")
% e.msg());
}
setOptions();
}
void RemoteStore::forkSlave()
{
int sockets[2];
if (socketpair(AF_UNIX, SOCK_STREAM, 0, sockets) == -1)
throw SysError("cannot create sockets");
fdSocket = sockets[0];
AutoCloseFD fdChild = sockets[1];
/* Start the worker. */
Path worker = getEnv("NIX_WORKER");
if (worker == "")
worker = nixBinDir + "/nix-worker";
child = fork();
switch (child) {
case -1:
throw SysError("unable to fork");
case 0:
try { /* child */
if (dup2(fdChild, STDOUT_FILENO) == -1)
throw SysError("dupping write side");
if (dup2(fdChild, STDIN_FILENO) == -1)
throw SysError("dupping read side");
close(fdSocket);
close(fdChild);
execlp(worker.c_str(), worker.c_str(), "--slave", NULL);
throw SysError(format("executing `%1%'") % worker);
} catch (std::exception & e) {
std::cerr << format("child error: %1%\n") % e.what();
}
quickExit(1);
}
fdChild.close();
}
void RemoteStore::connectToDaemon()
{
fdSocket = socket(PF_UNIX, SOCK_STREAM, 0);
if (fdSocket == -1)
throw SysError("cannot create Unix domain socket");
string socketPath = nixStateDir + DEFAULT_SOCKET_PATH;
/* Urgh, sockaddr_un allows path names of only 108 characters. So
chdir to the socket directory so that we can pass a relative
path name. !!! this is probably a bad idea in multi-threaded
applications... */
AutoCloseFD fdPrevDir = open(".", O_RDONLY);
if (fdPrevDir == -1) throw SysError("couldn't open current directory");
chdir(dirOf(socketPath).c_str());
Path socketPathRel = "./" + baseNameOf(socketPath);
struct sockaddr_un addr;
addr.sun_family = AF_UNIX;
if (socketPathRel.size() >= sizeof(addr.sun_path))
throw Error(format("socket path `%1%' is too long") % socketPathRel);
using namespace std;
strcpy(addr.sun_path, socketPathRel.c_str());
if (connect(fdSocket, (struct sockaddr *) &addr, sizeof(addr)) == -1)
throw SysError(format("cannot connect to daemon at `%1%'") % socketPath);
if (fchdir(fdPrevDir) == -1)
throw SysError("couldn't change back to previous directory");
}
RemoteStore::~RemoteStore()
{
try {
to.flush();
fdSocket.close();
if (child != -1)
child.wait(true);
} catch (...) {
ignoreException();
}
}
void RemoteStore::setOptions()
{
writeInt(wopSetOptions, to);
writeInt(keepFailed, to);
writeInt(keepGoing, to);
writeInt(tryFallback, to);
writeInt(verbosity, to);
writeInt(maxBuildJobs, to);
writeInt(maxSilentTime, to);
if (GET_PROTOCOL_MINOR(daemonVersion) >= 2)
writeInt(useBuildHook, to);
if (GET_PROTOCOL_MINOR(daemonVersion) >= 4) {
writeInt(buildVerbosity, to);
writeInt(logType, to);
writeInt(printBuildTrace, to);
}
if (GET_PROTOCOL_MINOR(daemonVersion) >= 6)
writeInt(buildCores, to);
processStderr();
}
bool RemoteStore::isValidPath(const Path & path)
{
openConnection();
writeInt(wopIsValidPath, to);
writeString(path, to);
processStderr();
unsigned int reply = readInt(from);
return reply != 0;
}
PathSet RemoteStore::queryValidPaths()
{
openConnection();
writeInt(wopQueryValidPaths, to);
processStderr();
return readStorePaths<PathSet>(from);
}
bool RemoteStore::hasSubstitutes(const Path & path)
{
openConnection();
writeInt(wopHasSubstitutes, to);
writeString(path, to);
processStderr();
unsigned int reply = readInt(from);
return reply != 0;
}
bool RemoteStore::querySubstitutablePathInfo(const Path & path,
SubstitutablePathInfo & info)
{
openConnection();
if (GET_PROTOCOL_MINOR(daemonVersion) < 3) return false;
writeInt(wopQuerySubstitutablePathInfo, to);
writeString(path, to);
processStderr();
unsigned int reply = readInt(from);
if (reply == 0) return false;
info.deriver = readString(from);
if (info.deriver != "") assertStorePath(info.deriver);
info.references = readStorePaths<PathSet>(from);
info.downloadSize = readLongLong(from);
info.narSize = GET_PROTOCOL_MINOR(daemonVersion) >= 7 ? readLongLong(from) : 0;
return true;
}
ValidPathInfo RemoteStore::queryPathInfo(const Path & path)
{
openConnection();
writeInt(wopQueryPathInfo, to);
writeString(path, to);
processStderr();
ValidPathInfo info;
info.path = path;
info.deriver = readString(from);
if (info.deriver != "") assertStorePath(info.deriver);
info.hash = parseHash(htSHA256, readString(from));
info.references = readStorePaths<PathSet>(from);
info.registrationTime = readInt(from);
info.narSize = readLongLong(from);
return info;
}
Hash RemoteStore::queryPathHash(const Path & path)
{
openConnection();
writeInt(wopQueryPathHash, to);
writeString(path, to);
processStderr();
string hash = readString(from);
return parseHash(htSHA256, hash);
}
void RemoteStore::queryReferences(const Path & path,
PathSet & references)
{
openConnection();
writeInt(wopQueryReferences, to);
writeString(path, to);
processStderr();
PathSet references2 = readStorePaths<PathSet>(from);
references.insert(references2.begin(), references2.end());
}
void RemoteStore::queryReferrers(const Path & path,
PathSet & referrers)
{
openConnection();
writeInt(wopQueryReferrers, to);
writeString(path, to);
processStderr();
PathSet referrers2 = readStorePaths<PathSet>(from);
referrers.insert(referrers2.begin(), referrers2.end());
}
Path RemoteStore::queryDeriver(const Path & path)
{
openConnection();
writeInt(wopQueryDeriver, to);
writeString(path, to);
processStderr();
Path drvPath = readString(from);
if (drvPath != "") assertStorePath(drvPath);
return drvPath;
}
PathSet RemoteStore::queryDerivationOutputs(const Path & path)
{
openConnection();
writeInt(wopQueryDerivationOutputs, to);
writeString(path, to);
processStderr();
return readStorePaths<PathSet>(from);
}
PathSet RemoteStore::queryDerivationOutputNames(const Path & path)
{
openConnection();
writeInt(wopQueryDerivationOutputNames, to);
writeString(path, to);
processStderr();
return readStrings<PathSet>(from);
}
Path RemoteStore::addToStore(const Path & _srcPath,
bool recursive, HashType hashAlgo, PathFilter & filter)
{
openConnection();
Path srcPath(absPath(_srcPath));
writeInt(wopAddToStore, to);
writeString(baseNameOf(srcPath), to);
/* backwards compatibility hack */
writeInt((hashAlgo == htSHA256 && recursive) ? 0 : 1, to);
writeInt(recursive ? 1 : 0, to);
writeString(printHashType(hashAlgo), to);
dumpPath(srcPath, to, filter);
processStderr();
return readStorePath(from);
}
Path RemoteStore::addTextToStore(const string & name, const string & s,
const PathSet & references)
{
openConnection();
writeInt(wopAddTextToStore, to);
writeString(name, to);
writeString(s, to);
writeStrings(references, to);
processStderr();
return readStorePath(from);
}
void RemoteStore::exportPath(const Path & path, bool sign,
Sink & sink)
{
openConnection();
writeInt(wopExportPath, to);
writeString(path, to);
writeInt(sign ? 1 : 0, to);
processStderr(&sink); /* sink receives the actual data */
readInt(from);
}
Paths RemoteStore::importPaths(bool requireSignature, Source & source)
{
openConnection();
writeInt(wopImportPaths, to);
/* We ignore requireSignature, since the worker forces it to true
anyway. */
processStderr(0, &source);
return readStorePaths<Paths>(from);
}
void RemoteStore::buildDerivations(const PathSet & drvPaths)
{
openConnection();
writeInt(wopBuildDerivations, to);
writeStrings(drvPaths, to);
processStderr();
readInt(from);
}
void RemoteStore::ensurePath(const Path & path)
{
openConnection();
writeInt(wopEnsurePath, to);
writeString(path, to);
processStderr();
readInt(from);
}
void RemoteStore::addTempRoot(const Path & path)
{
openConnection();
writeInt(wopAddTempRoot, to);
writeString(path, to);
processStderr();
readInt(from);
}
void RemoteStore::addIndirectRoot(const Path & path)
{
openConnection();
writeInt(wopAddIndirectRoot, to);
writeString(path, to);
processStderr();
readInt(from);
}
void RemoteStore::syncWithGC()
{
openConnection();
writeInt(wopSyncWithGC, to);
processStderr();
readInt(from);
}
Roots RemoteStore::findRoots()
{
openConnection();
writeInt(wopFindRoots, to);
processStderr();
unsigned int count = readInt(from);
Roots result;
while (count--) {
Path link = readString(from);
Path target = readStorePath(from);
result[link] = target;
}
return result;
}
void RemoteStore::collectGarbage(const GCOptions & options, GCResults & results)
{
openConnection();
writeInt(wopCollectGarbage, to);
writeInt(options.action, to);
writeStrings(options.pathsToDelete, to);
writeInt(options.ignoreLiveness, to);
writeLongLong(options.maxFreed, to);
writeInt(0, to);
if (GET_PROTOCOL_MINOR(daemonVersion) >= 5) {
/* removed options */
writeInt(0, to);
writeInt(0, to);
}
processStderr();
results.paths = readStrings<PathSet>(from);
results.bytesFreed = readLongLong(from);
results.blocksFreed = readLongLong(from);
}
PathSet RemoteStore::queryFailedPaths()
{
openConnection();
writeInt(wopQueryFailedPaths, to);
processStderr();
return readStorePaths<PathSet>(from);
}
void RemoteStore::clearFailedPaths(const PathSet & paths)
{
openConnection();
writeInt(wopClearFailedPaths, to);
writeStrings(paths, to);
processStderr();
readInt(from);
}
void RemoteStore::processStderr(Sink * sink, Source * source)
{
to.flush();
unsigned int msg;
while ((msg = readInt(from)) == STDERR_NEXT
|| msg == STDERR_READ || msg == STDERR_WRITE) {
if (msg == STDERR_WRITE) {
string s = readString(from);
if (!sink) throw Error("no sink");
(*sink)((const unsigned char *) s.data(), s.size());
}
else if (msg == STDERR_READ) {
if (!source) throw Error("no source");
size_t len = readInt(from);
unsigned char * buf = new unsigned char[len];
AutoDeleteArray<unsigned char> d(buf);
writeString(buf, source->read(buf, len), to);
to.flush();
}
else {
string s = readString(from);
writeToStderr((const unsigned char *) s.data(), s.size());
}
}
if (msg == STDERR_ERROR) {
string error = readString(from);
unsigned int status = GET_PROTOCOL_MINOR(daemonVersion) >= 8 ? readInt(from) : 1;
throw Error(format("%1%") % error, status);
}
else if (msg != STDERR_LAST)
throw Error("protocol error processing standard error");
}
}