lix/src/libstore/remote-store.cc
Eelco Dolstra a9c4f66cfb * Allow unprivileged users to run the garbage collector and to do
`nix-store --delete'.  But unprivileged users are not allowed to
  ignore liveness.
* `nix-store --delete --ignore-liveness': ignore the runtime roots as
  well.
2006-12-05 02:18:46 +00:00

341 lines
7.6 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>
namespace nix {
Path readStorePath(Source & from)
{
Path path = readString(from);
assertStorePath(path);
return path;
}
PathSet readStorePaths(Source & from)
{
PathSet paths = readStringSet(from);
for (PathSet::iterator i = paths.begin(); i != paths.end(); ++i)
assertStorePath(*i);
return paths;
}
RemoteStore::RemoteStore()
{
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);
writeInt(verbosity, to);
unsigned int magic = readInt(from);
if (magic != WORKER_MAGIC_2) throw Error("protocol mismatch");
processStderr();
} catch (Error & e) {
throw Error(format("cannot start worker (%1%)")
% e.msg());
}
}
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";
string verbosityArg = "-";
for (int i = 1; i < verbosity; ++i)
verbosityArg += "v";
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",
/* hacky - must be at the end */
verbosityArg == "-" ? NULL : verbosityArg.c_str(),
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;
struct sockaddr_un addr;
addr.sun_family = AF_UNIX;
if (socketPath.size() >= sizeof(addr.sun_path))
throw Error(format("socket path `%1%' is too long") % socketPath);
strcpy(addr.sun_path, socketPath.c_str());
if (connect(fdSocket, (struct sockaddr *) &addr, sizeof(addr)) == -1)
throw SysError(format("cannot connect to daemon at `%1%'") % socketPath);
}
RemoteStore::~RemoteStore()
{
try {
fdSocket.close();
if (child != -1)
child.wait(true);
} catch (Error & e) {
printMsg(lvlError, format("error (ignored): %1%") % e.msg());
}
}
bool RemoteStore::isValidPath(const Path & path)
{
writeInt(wopIsValidPath, to);
writeString(path, to);
processStderr();
unsigned int reply = readInt(from);
return reply != 0;
}
Substitutes RemoteStore::querySubstitutes(const Path & path)
{
throw Error("not implemented 2");
}
bool RemoteStore::hasSubstitutes(const Path & path)
{
writeInt(wopHasSubstitutes, to);
writeString(path, to);
processStderr();
unsigned int reply = readInt(from);
return reply != 0;
}
Hash RemoteStore::queryPathHash(const Path & path)
{
writeInt(wopQueryPathHash, to);
writeString(path, to);
processStderr();
string hash = readString(from);
return parseHash(htSHA256, hash);
}
void RemoteStore::queryReferences(const Path & path,
PathSet & references)
{
writeInt(wopQueryReferences, to);
writeString(path, to);
processStderr();
PathSet references2 = readStorePaths(from);
references.insert(references2.begin(), references2.end());
}
void RemoteStore::queryReferrers(const Path & path,
PathSet & referrers)
{
writeInt(wopQueryReferrers, to);
writeString(path, to);
processStderr();
PathSet referrers2 = readStorePaths(from);
referrers.insert(referrers2.begin(), referrers2.end());
}
Path RemoteStore::addToStore(const Path & _srcPath, bool fixed,
bool recursive, string hashAlgo)
{
Path srcPath(absPath(_srcPath));
writeInt(wopAddToStore, to);
writeString(baseNameOf(srcPath), to);
writeInt(fixed ? 1 : 0, to);
writeInt(recursive ? 1 : 0, to);
writeString(hashAlgo, to);
dumpPath(srcPath, to);
processStderr();
Path path = readStorePath(from);
return path;
}
Path RemoteStore::addTextToStore(const string & suffix, const string & s,
const PathSet & references)
{
writeInt(wopAddTextToStore, to);
writeString(suffix, to);
writeString(s, to);
writeStringSet(references, to);
processStderr();
Path path = readStorePath(from);
return path;
}
void RemoteStore::buildDerivations(const PathSet & drvPaths)
{
writeInt(wopBuildDerivations, to);
writeStringSet(drvPaths, to);
processStderr();
readInt(from);
}
void RemoteStore::ensurePath(const Path & path)
{
writeInt(wopEnsurePath, to);
writeString(path, to);
processStderr();
readInt(from);
}
void RemoteStore::addTempRoot(const Path & path)
{
writeInt(wopAddTempRoot, to);
writeString(path, to);
processStderr();
readInt(from);
}
void RemoteStore::addIndirectRoot(const Path & path)
{
writeInt(wopAddIndirectRoot, to);
writeString(path, to);
processStderr();
readInt(from);
}
void RemoteStore::syncWithGC()
{
writeInt(wopSyncWithGC, to);
processStderr();
readInt(from);
}
Roots RemoteStore::findRoots()
{
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(GCAction action, const PathSet & pathsToDelete,
bool ignoreLiveness, PathSet & result, unsigned long long & bytesFreed)
{
result.clear();
bytesFreed = 0;
writeInt(wopCollectGarbage, to);
writeInt(action, to);
writeStringSet(pathsToDelete, to);
writeInt(ignoreLiveness, to);
processStderr();
result = readStringSet(from);
/* Ugh - NAR integers are 64 bits, but read/writeInt() aren't. */
unsigned int lo = readInt(from);
unsigned int hi = readInt(from);
bytesFreed = (((unsigned long long) hi) << 32) | lo;
}
void RemoteStore::processStderr()
{
unsigned int msg;
while ((msg = readInt(from)) == STDERR_NEXT) {
string s = readString(from);
writeToStderr((unsigned char *) s.c_str(), s.size());
}
if (msg == STDERR_ERROR)
throw Error(readString(from));
else if (msg != STDERR_LAST)
throw Error("protocol error processing standard error");
}
}