forked from lix-project/lix
908 lines
26 KiB
C++
908 lines
26 KiB
C++
#include "shared.hh"
|
|
#include "local-store.hh"
|
|
#include "util.hh"
|
|
#include "serialise.hh"
|
|
#include "worker-protocol.hh"
|
|
#include "archive.hh"
|
|
#include "globals.hh"
|
|
|
|
#include <iostream>
|
|
#include <cstring>
|
|
#include <unistd.h>
|
|
#include <signal.h>
|
|
#include <sys/types.h>
|
|
#include <sys/wait.h>
|
|
#include <sys/stat.h>
|
|
#include <sys/socket.h>
|
|
#include <sys/un.h>
|
|
#include <fcntl.h>
|
|
#include <errno.h>
|
|
|
|
using namespace nix;
|
|
|
|
|
|
/* On platforms that have O_ASYNC, we can detect when a client
|
|
disconnects and immediately kill any ongoing builds. On platforms
|
|
that lack it, we only notice the disconnection the next time we try
|
|
to write to the client. So if you have a builder that never
|
|
generates output on stdout/stderr, the worker will never notice
|
|
that the client has disconnected until the builder terminates. */
|
|
#ifdef O_ASYNC
|
|
#define HAVE_HUP_NOTIFICATION
|
|
#ifndef SIGPOLL
|
|
#define SIGPOLL SIGIO
|
|
#endif
|
|
#endif
|
|
|
|
|
|
static FdSource from(STDIN_FILENO);
|
|
static FdSink to(STDOUT_FILENO);
|
|
|
|
bool canSendStderr;
|
|
pid_t myPid;
|
|
|
|
|
|
|
|
/* This function is called anytime we want to write something to
|
|
stderr. If we're in a state where the protocol allows it (i.e.,
|
|
when canSendStderr), send the message to the client over the
|
|
socket. */
|
|
static void tunnelStderr(const unsigned char * buf, size_t count)
|
|
{
|
|
/* Don't send the message to the client if we're a child of the
|
|
process handling the connection. Otherwise we could screw up
|
|
the protocol. It's up to the parent to redirect stderr and
|
|
send it to the client somehow (e.g., as in build.cc). */
|
|
if (canSendStderr && myPid == getpid()) {
|
|
try {
|
|
writeInt(STDERR_NEXT, to);
|
|
writeString(buf, count, to);
|
|
to.flush();
|
|
} catch (...) {
|
|
/* Write failed; that means that the other side is
|
|
gone. */
|
|
canSendStderr = false;
|
|
throw;
|
|
}
|
|
} else
|
|
writeFull(STDERR_FILENO, buf, count);
|
|
}
|
|
|
|
|
|
/* Return true if the remote side has closed its end of the
|
|
connection, false otherwise. Should not be called on any socket on
|
|
which we expect input! */
|
|
static bool isFarSideClosed(int socket)
|
|
{
|
|
struct timeval timeout;
|
|
timeout.tv_sec = timeout.tv_usec = 0;
|
|
|
|
fd_set fds;
|
|
FD_ZERO(&fds);
|
|
FD_SET(socket, &fds);
|
|
|
|
while (select(socket + 1, &fds, 0, 0, &timeout) == -1)
|
|
if (errno != EINTR) throw SysError("select()");
|
|
|
|
if (!FD_ISSET(socket, &fds)) return false;
|
|
|
|
/* Destructive read to determine whether the select() marked the
|
|
socket as readable because there is actual input or because
|
|
we've reached EOF (i.e., a read of size 0 is available). */
|
|
char c;
|
|
int rd;
|
|
if ((rd = read(socket, &c, 1)) > 0)
|
|
throw Error("EOF expected (protocol error?)");
|
|
else if (rd == -1 && errno != ECONNRESET)
|
|
throw SysError("expected connection reset or EOF");
|
|
|
|
return true;
|
|
}
|
|
|
|
|
|
/* A SIGPOLL signal is received when data is available on the client
|
|
communication socket, or when the client has closed its side of the
|
|
socket. This handler is enabled at precisely those moments in the
|
|
protocol when we're doing work and the client is supposed to be
|
|
quiet. Thus, if we get a SIGPOLL signal, it means that the client
|
|
has quit. So we should quit as well.
|
|
|
|
Too bad most operating systems don't support the POLL_HUP value for
|
|
si_code in siginfo_t. That would make most of the SIGPOLL
|
|
complexity unnecessary, i.e., we could just enable SIGPOLL all the
|
|
time and wouldn't have to worry about races. */
|
|
static void sigPollHandler(int sigNo)
|
|
{
|
|
using namespace std;
|
|
try {
|
|
/* Check that the far side actually closed. We're still
|
|
getting spurious signals every once in a while. I.e.,
|
|
there is no input available, but we get a signal with
|
|
POLL_IN set. Maybe it's delayed or something. */
|
|
if (isFarSideClosed(from.fd)) {
|
|
if (!blockInt) {
|
|
_isInterrupted = 1;
|
|
blockInt = 1;
|
|
canSendStderr = false;
|
|
const char * s = "SIGPOLL\n";
|
|
write(STDERR_FILENO, s, strlen(s));
|
|
}
|
|
} else {
|
|
const char * s = "spurious SIGPOLL\n";
|
|
write(STDERR_FILENO, s, strlen(s));
|
|
}
|
|
}
|
|
catch (Error & e) {
|
|
/* Shouldn't happen. */
|
|
string s = "impossible: " + e.msg() + '\n';
|
|
write(STDERR_FILENO, s.data(), s.size());
|
|
throw;
|
|
}
|
|
}
|
|
|
|
|
|
static void setSigPollAction(bool enable)
|
|
{
|
|
#ifdef HAVE_HUP_NOTIFICATION
|
|
struct sigaction act, oact;
|
|
act.sa_handler = enable ? sigPollHandler : SIG_IGN;
|
|
sigfillset(&act.sa_mask);
|
|
act.sa_flags = 0;
|
|
if (sigaction(SIGPOLL, &act, &oact))
|
|
throw SysError("setting handler for SIGPOLL");
|
|
#endif
|
|
}
|
|
|
|
|
|
/* startWork() means that we're starting an operation for which we
|
|
want to send out stderr to the client. */
|
|
static void startWork()
|
|
{
|
|
canSendStderr = true;
|
|
|
|
/* Handle client death asynchronously. */
|
|
setSigPollAction(true);
|
|
|
|
/* Of course, there is a race condition here: the socket could
|
|
have closed between when we last read from / wrote to it, and
|
|
between the time we set the handler for SIGPOLL. In that case
|
|
we won't get the signal. So do a non-blocking select() to find
|
|
out if any input is available on the socket. If there is, it
|
|
has to be the 0-byte read that indicates that the socket has
|
|
closed. */
|
|
if (isFarSideClosed(from.fd)) {
|
|
_isInterrupted = 1;
|
|
checkInterrupt();
|
|
}
|
|
}
|
|
|
|
|
|
/* stopWork() means that we're done; stop sending stderr to the
|
|
client. */
|
|
static void stopWork(bool success = true, const string & msg = "", unsigned int status = 0)
|
|
{
|
|
/* Stop handling async client death; we're going to a state where
|
|
we're either sending or receiving from the client, so we'll be
|
|
notified of client death anyway. */
|
|
setSigPollAction(false);
|
|
|
|
canSendStderr = false;
|
|
|
|
if (success)
|
|
writeInt(STDERR_LAST, to);
|
|
else {
|
|
writeInt(STDERR_ERROR, to);
|
|
writeString(msg, to);
|
|
if (status != 0) writeInt(status, to);
|
|
}
|
|
}
|
|
|
|
|
|
struct TunnelSink : Sink
|
|
{
|
|
Sink & to;
|
|
TunnelSink(Sink & to) : to(to) { }
|
|
virtual void operator () (const unsigned char * data, size_t len)
|
|
{
|
|
writeInt(STDERR_WRITE, to);
|
|
writeString(data, len, to);
|
|
}
|
|
};
|
|
|
|
|
|
struct TunnelSource : BufferedSource
|
|
{
|
|
Source & from;
|
|
TunnelSource(Source & from) : from(from) { }
|
|
size_t readUnbuffered(unsigned char * data, size_t len)
|
|
{
|
|
/* Careful: we're going to receive data from the client now,
|
|
so we have to disable the SIGPOLL handler. */
|
|
setSigPollAction(false);
|
|
canSendStderr = false;
|
|
|
|
writeInt(STDERR_READ, to);
|
|
writeInt(len, to);
|
|
to.flush();
|
|
size_t n = readString(data, len, from);
|
|
|
|
startWork();
|
|
if (n == 0) throw EndOfFile("unexpected end-of-file");
|
|
return n;
|
|
}
|
|
};
|
|
|
|
|
|
/* If the NAR archive contains a single file at top-level, then save
|
|
the contents of the file to `s'. Otherwise barf. */
|
|
struct RetrieveRegularNARSink : ParseSink
|
|
{
|
|
bool regular;
|
|
string s;
|
|
|
|
RetrieveRegularNARSink() : regular(true) { }
|
|
|
|
void createDirectory(const Path & path)
|
|
{
|
|
regular = false;
|
|
}
|
|
|
|
void receiveContents(unsigned char * data, unsigned int len)
|
|
{
|
|
s.append((const char *) data, len);
|
|
}
|
|
|
|
void createSymlink(const Path & path, const string & target)
|
|
{
|
|
regular = false;
|
|
}
|
|
};
|
|
|
|
|
|
/* Adapter class of a Source that saves all data read to `s'. */
|
|
struct SavingSourceAdapter : Source
|
|
{
|
|
Source & orig;
|
|
string s;
|
|
SavingSourceAdapter(Source & orig) : orig(orig) { }
|
|
size_t read(unsigned char * data, size_t len)
|
|
{
|
|
size_t n = orig.read(data, len);
|
|
s.append((const char *) data, n);
|
|
return n;
|
|
}
|
|
};
|
|
|
|
|
|
static void performOp(unsigned int clientVersion,
|
|
Source & from, Sink & to, unsigned int op)
|
|
{
|
|
switch (op) {
|
|
|
|
#if 0
|
|
case wopQuit: {
|
|
/* Close the database. */
|
|
store.reset((StoreAPI *) 0);
|
|
writeInt(1, to);
|
|
break;
|
|
}
|
|
#endif
|
|
|
|
case wopIsValidPath: {
|
|
Path path = readStorePath(from);
|
|
startWork();
|
|
bool result = store->isValidPath(path);
|
|
stopWork();
|
|
writeInt(result, to);
|
|
break;
|
|
}
|
|
|
|
case wopHasSubstitutes: {
|
|
Path path = readStorePath(from);
|
|
startWork();
|
|
bool result = store->hasSubstitutes(path);
|
|
stopWork();
|
|
writeInt(result, to);
|
|
break;
|
|
}
|
|
|
|
case wopQueryPathHash: {
|
|
Path path = readStorePath(from);
|
|
startWork();
|
|
Hash hash = store->queryPathHash(path);
|
|
stopWork();
|
|
writeString(printHash(hash), to);
|
|
break;
|
|
}
|
|
|
|
case wopQueryReferences:
|
|
case wopQueryReferrers:
|
|
case wopQueryDerivationOutputs: {
|
|
Path path = readStorePath(from);
|
|
startWork();
|
|
PathSet paths;
|
|
if (op == wopQueryReferences)
|
|
store->queryReferences(path, paths);
|
|
else if (op == wopQueryReferrers)
|
|
store->queryReferrers(path, paths);
|
|
else paths = store->queryDerivationOutputs(path);
|
|
stopWork();
|
|
writeStrings(paths, to);
|
|
break;
|
|
}
|
|
|
|
case wopQueryDerivationOutputNames: {
|
|
Path path = readStorePath(from);
|
|
startWork();
|
|
StringSet names;
|
|
names = store->queryDerivationOutputNames(path);
|
|
stopWork();
|
|
writeStrings(names, to);
|
|
break;
|
|
}
|
|
|
|
case wopQueryDeriver: {
|
|
Path path = readStorePath(from);
|
|
startWork();
|
|
Path deriver = store->queryDeriver(path);
|
|
stopWork();
|
|
writeString(deriver, to);
|
|
break;
|
|
}
|
|
|
|
case wopAddToStore: {
|
|
string baseName = readString(from);
|
|
bool fixed = readInt(from) == 1; /* obsolete */
|
|
bool recursive = readInt(from) == 1;
|
|
string s = readString(from);
|
|
/* Compatibility hack. */
|
|
if (!fixed) {
|
|
s = "sha256";
|
|
recursive = true;
|
|
}
|
|
HashType hashAlgo = parseHashType(s);
|
|
|
|
SavingSourceAdapter savedNAR(from);
|
|
RetrieveRegularNARSink savedRegular;
|
|
|
|
if (recursive) {
|
|
/* Get the entire NAR dump from the client and save it to
|
|
a string so that we can pass it to
|
|
addToStoreFromDump(). */
|
|
ParseSink sink; /* null sink; just parse the NAR */
|
|
parseDump(sink, savedNAR);
|
|
} else
|
|
parseDump(savedRegular, from);
|
|
|
|
startWork();
|
|
if (!savedRegular.regular) throw Error("regular file expected");
|
|
Path path = dynamic_cast<LocalStore *>(store.get())
|
|
->addToStoreFromDump(recursive ? savedNAR.s : savedRegular.s, baseName, recursive, hashAlgo);
|
|
stopWork();
|
|
|
|
writeString(path, to);
|
|
break;
|
|
}
|
|
|
|
case wopAddTextToStore: {
|
|
string suffix = readString(from);
|
|
string s = readString(from);
|
|
PathSet refs = readStorePaths<PathSet>(from);
|
|
startWork();
|
|
Path path = store->addTextToStore(suffix, s, refs);
|
|
stopWork();
|
|
writeString(path, to);
|
|
break;
|
|
}
|
|
|
|
case wopExportPath: {
|
|
Path path = readStorePath(from);
|
|
bool sign = readInt(from) == 1;
|
|
startWork();
|
|
TunnelSink sink(to);
|
|
store->exportPath(path, sign, sink);
|
|
stopWork();
|
|
writeInt(1, to);
|
|
break;
|
|
}
|
|
|
|
case wopImportPaths: {
|
|
startWork();
|
|
TunnelSource source(from);
|
|
Paths paths = store->importPaths(true, source);
|
|
stopWork();
|
|
writeStrings(paths, to);
|
|
break;
|
|
}
|
|
|
|
case wopBuildPaths: {
|
|
PathSet drvs = readStorePaths<PathSet>(from);
|
|
startWork();
|
|
store->buildPaths(drvs);
|
|
stopWork();
|
|
writeInt(1, to);
|
|
break;
|
|
}
|
|
|
|
case wopEnsurePath: {
|
|
Path path = readStorePath(from);
|
|
startWork();
|
|
store->ensurePath(path);
|
|
stopWork();
|
|
writeInt(1, to);
|
|
break;
|
|
}
|
|
|
|
case wopAddTempRoot: {
|
|
Path path = readStorePath(from);
|
|
startWork();
|
|
store->addTempRoot(path);
|
|
stopWork();
|
|
writeInt(1, to);
|
|
break;
|
|
}
|
|
|
|
case wopAddIndirectRoot: {
|
|
Path path = absPath(readString(from));
|
|
startWork();
|
|
store->addIndirectRoot(path);
|
|
stopWork();
|
|
writeInt(1, to);
|
|
break;
|
|
}
|
|
|
|
case wopSyncWithGC: {
|
|
startWork();
|
|
store->syncWithGC();
|
|
stopWork();
|
|
writeInt(1, to);
|
|
break;
|
|
}
|
|
|
|
case wopFindRoots: {
|
|
startWork();
|
|
Roots roots = store->findRoots();
|
|
stopWork();
|
|
writeInt(roots.size(), to);
|
|
for (Roots::iterator i = roots.begin(); i != roots.end(); ++i) {
|
|
writeString(i->first, to);
|
|
writeString(i->second, to);
|
|
}
|
|
break;
|
|
}
|
|
|
|
case wopCollectGarbage: {
|
|
GCOptions options;
|
|
options.action = (GCOptions::GCAction) readInt(from);
|
|
options.pathsToDelete = readStorePaths<PathSet>(from);
|
|
options.ignoreLiveness = readInt(from);
|
|
options.maxFreed = readLongLong(from);
|
|
readInt(from); // obsolete field
|
|
if (GET_PROTOCOL_MINOR(clientVersion) >= 5) {
|
|
/* removed options */
|
|
readInt(from);
|
|
readInt(from);
|
|
}
|
|
|
|
GCResults results;
|
|
|
|
startWork();
|
|
if (options.ignoreLiveness)
|
|
throw Error("you are not allowed to ignore liveness");
|
|
store->collectGarbage(options, results);
|
|
stopWork();
|
|
|
|
writeStrings(results.paths, to);
|
|
writeLongLong(results.bytesFreed, to);
|
|
writeLongLong(results.blocksFreed, to);
|
|
|
|
break;
|
|
}
|
|
|
|
case wopSetOptions: {
|
|
keepFailed = readInt(from) != 0;
|
|
keepGoing = readInt(from) != 0;
|
|
tryFallback = readInt(from) != 0;
|
|
verbosity = (Verbosity) readInt(from);
|
|
maxBuildJobs = readInt(from);
|
|
maxSilentTime = readInt(from);
|
|
if (GET_PROTOCOL_MINOR(clientVersion) >= 2)
|
|
useBuildHook = readInt(from) != 0;
|
|
if (GET_PROTOCOL_MINOR(clientVersion) >= 4) {
|
|
buildVerbosity = (Verbosity) readInt(from);
|
|
logType = (LogType) readInt(from);
|
|
printBuildTrace = readInt(from) != 0;
|
|
}
|
|
if (GET_PROTOCOL_MINOR(clientVersion) >= 6)
|
|
buildCores = readInt(from);
|
|
if (GET_PROTOCOL_MINOR(clientVersion) >= 10) {
|
|
int x = readInt(from);
|
|
Strings ss;
|
|
ss.push_back(x == 0 ? "false" : "true");
|
|
overrideSetting("build-use-substitutes", ss);
|
|
}
|
|
startWork();
|
|
stopWork();
|
|
break;
|
|
}
|
|
|
|
case wopQuerySubstitutablePathInfo: {
|
|
Path path = absPath(readString(from));
|
|
startWork();
|
|
SubstitutablePathInfos infos;
|
|
store->querySubstitutablePathInfos(singleton<PathSet>(path), infos);
|
|
stopWork();
|
|
SubstitutablePathInfos::iterator i = infos.find(path);
|
|
if (i == infos.end())
|
|
writeInt(0, to);
|
|
else {
|
|
writeInt(1, to);
|
|
writeString(i->second.deriver, to);
|
|
writeStrings(i->second.references, to);
|
|
writeLongLong(i->second.downloadSize, to);
|
|
if (GET_PROTOCOL_MINOR(clientVersion) >= 7)
|
|
writeLongLong(i->second.narSize, to);
|
|
}
|
|
break;
|
|
}
|
|
|
|
case wopQuerySubstitutablePathInfos: {
|
|
PathSet paths = readStorePaths<PathSet>(from);
|
|
startWork();
|
|
SubstitutablePathInfos infos;
|
|
store->querySubstitutablePathInfos(paths, infos);
|
|
stopWork();
|
|
writeInt(infos.size(), to);
|
|
foreach (SubstitutablePathInfos::iterator, i, infos) {
|
|
writeString(i->first, to);
|
|
writeString(i->second.deriver, to);
|
|
writeStrings(i->second.references, to);
|
|
writeLongLong(i->second.downloadSize, to);
|
|
writeLongLong(i->second.narSize, to);
|
|
}
|
|
break;
|
|
}
|
|
|
|
case wopQueryValidPaths: {
|
|
startWork();
|
|
PathSet paths = store->queryValidPaths();
|
|
stopWork();
|
|
writeStrings(paths, to);
|
|
break;
|
|
}
|
|
|
|
case wopQueryFailedPaths: {
|
|
startWork();
|
|
PathSet paths = store->queryFailedPaths();
|
|
stopWork();
|
|
writeStrings(paths, to);
|
|
break;
|
|
}
|
|
|
|
case wopClearFailedPaths: {
|
|
PathSet paths = readStrings<PathSet>(from);
|
|
startWork();
|
|
store->clearFailedPaths(paths);
|
|
stopWork();
|
|
writeInt(1, to);
|
|
break;
|
|
}
|
|
|
|
case wopQueryPathInfo: {
|
|
Path path = readStorePath(from);
|
|
startWork();
|
|
ValidPathInfo info = store->queryPathInfo(path);
|
|
stopWork();
|
|
writeString(info.deriver, to);
|
|
writeString(printHash(info.hash), to);
|
|
writeStrings(info.references, to);
|
|
writeInt(info.registrationTime, to);
|
|
writeLongLong(info.narSize, to);
|
|
break;
|
|
}
|
|
|
|
default:
|
|
throw Error(format("invalid operation %1%") % op);
|
|
}
|
|
}
|
|
|
|
|
|
static void processConnection()
|
|
{
|
|
canSendStderr = false;
|
|
myPid = getpid();
|
|
writeToStderr = tunnelStderr;
|
|
|
|
#ifdef HAVE_HUP_NOTIFICATION
|
|
/* Allow us to receive SIGPOLL for events on the client socket. */
|
|
setSigPollAction(false);
|
|
if (fcntl(from.fd, F_SETOWN, getpid()) == -1)
|
|
throw SysError("F_SETOWN");
|
|
if (fcntl(from.fd, F_SETFL, fcntl(from.fd, F_GETFL, 0) | O_ASYNC) == -1)
|
|
throw SysError("F_SETFL");
|
|
#endif
|
|
|
|
/* Exchange the greeting. */
|
|
unsigned int magic = readInt(from);
|
|
if (magic != WORKER_MAGIC_1) throw Error("protocol mismatch");
|
|
writeInt(WORKER_MAGIC_2, to);
|
|
writeInt(PROTOCOL_VERSION, to);
|
|
to.flush();
|
|
unsigned int clientVersion = readInt(from);
|
|
|
|
/* Send startup error messages to the client. */
|
|
startWork();
|
|
|
|
try {
|
|
|
|
/* If we can't accept clientVersion, then throw an error
|
|
*here* (not above). */
|
|
|
|
#if 0
|
|
/* Prevent users from doing something very dangerous. */
|
|
if (geteuid() == 0 &&
|
|
querySetting("build-users-group", "") == "")
|
|
throw Error("if you run `nix-worker' as root, then you MUST set `build-users-group'!");
|
|
#endif
|
|
|
|
bool reserveSpace = true;
|
|
if (GET_PROTOCOL_MINOR(clientVersion) >= 11)
|
|
reserveSpace = readInt(from) != 0;
|
|
|
|
/* Open the store. */
|
|
store = boost::shared_ptr<StoreAPI>(new LocalStore(reserveSpace));
|
|
|
|
stopWork();
|
|
to.flush();
|
|
|
|
} catch (Error & e) {
|
|
stopWork(false, e.msg());
|
|
to.flush();
|
|
return;
|
|
}
|
|
|
|
/* Process client requests. */
|
|
unsigned int opCount = 0;
|
|
|
|
while (true) {
|
|
WorkerOp op;
|
|
try {
|
|
op = (WorkerOp) readInt(from);
|
|
} catch (EndOfFile & e) {
|
|
break;
|
|
}
|
|
|
|
opCount++;
|
|
|
|
try {
|
|
performOp(clientVersion, from, to, op);
|
|
} catch (Error & e) {
|
|
/* If we're not in a state were we can send replies, then
|
|
something went wrong processing the input of the
|
|
client. This can happen especially if I/O errors occur
|
|
during addTextToStore() / importPath(). If that
|
|
happens, just send the error message and exit. */
|
|
bool errorAllowed = canSendStderr;
|
|
if (!errorAllowed) printMsg(lvlError, format("error processing client input: %1%") % e.msg());
|
|
stopWork(false, e.msg(), GET_PROTOCOL_MINOR(clientVersion) >= 8 ? e.status : 0);
|
|
if (!errorAllowed) break;
|
|
}
|
|
|
|
to.flush();
|
|
|
|
assert(!canSendStderr);
|
|
};
|
|
|
|
printMsg(lvlError, format("%1% worker operations") % opCount);
|
|
}
|
|
|
|
|
|
static void sigChldHandler(int sigNo)
|
|
{
|
|
/* Reap all dead children. */
|
|
while (waitpid(-1, 0, WNOHANG) > 0) ;
|
|
}
|
|
|
|
|
|
static void setSigChldAction(bool autoReap)
|
|
{
|
|
struct sigaction act, oact;
|
|
act.sa_handler = autoReap ? sigChldHandler : SIG_DFL;
|
|
sigfillset(&act.sa_mask);
|
|
act.sa_flags = 0;
|
|
if (sigaction(SIGCHLD, &act, &oact))
|
|
throw SysError("setting SIGCHLD handler");
|
|
}
|
|
|
|
|
|
#define SD_LISTEN_FDS_START 3
|
|
|
|
|
|
static void daemonLoop()
|
|
{
|
|
/* Get rid of children automatically; don't let them become
|
|
zombies. */
|
|
setSigChldAction(true);
|
|
|
|
AutoCloseFD fdSocket;
|
|
|
|
/* Handle socket-based activation by systemd. */
|
|
if (getEnv("LISTEN_FDS") != "") {
|
|
if (getEnv("LISTEN_PID") != int2String(getpid()) || getEnv("LISTEN_FDS") != "1")
|
|
throw Error("unexpected systemd environment variables");
|
|
fdSocket = SD_LISTEN_FDS_START;
|
|
}
|
|
|
|
/* Otherwise, create and bind to a Unix domain socket. */
|
|
else {
|
|
|
|
/* Create and bind to a Unix domain socket. */
|
|
fdSocket = socket(PF_UNIX, SOCK_STREAM, 0);
|
|
if (fdSocket == -1)
|
|
throw SysError("cannot create Unix domain socket");
|
|
|
|
string socketPath = nixStateDir + DEFAULT_SOCKET_PATH;
|
|
|
|
createDirs(dirOf(socketPath));
|
|
|
|
/* 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. */
|
|
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);
|
|
strcpy(addr.sun_path, socketPathRel.c_str());
|
|
|
|
unlink(socketPath.c_str());
|
|
|
|
/* Make sure that the socket is created with 0666 permission
|
|
(everybody can connect --- provided they have access to the
|
|
directory containing the socket). */
|
|
mode_t oldMode = umask(0111);
|
|
int res = bind(fdSocket, (struct sockaddr *) &addr, sizeof(addr));
|
|
umask(oldMode);
|
|
if (res == -1)
|
|
throw SysError(format("cannot bind to socket `%1%'") % socketPath);
|
|
|
|
chdir("/"); /* back to the root */
|
|
|
|
if (listen(fdSocket, 5) == -1)
|
|
throw SysError(format("cannot listen on socket `%1%'") % socketPath);
|
|
}
|
|
|
|
closeOnExec(fdSocket);
|
|
|
|
/* Loop accepting connections. */
|
|
while (1) {
|
|
|
|
try {
|
|
/* Important: the server process *cannot* open the SQLite
|
|
database, because it doesn't like forks very much. */
|
|
assert(!store);
|
|
|
|
/* Accept a connection. */
|
|
struct sockaddr_un remoteAddr;
|
|
socklen_t remoteAddrLen = sizeof(remoteAddr);
|
|
|
|
AutoCloseFD remote = accept(fdSocket,
|
|
(struct sockaddr *) &remoteAddr, &remoteAddrLen);
|
|
checkInterrupt();
|
|
if (remote == -1) {
|
|
if (errno == EINTR)
|
|
continue;
|
|
else
|
|
throw SysError("accepting connection");
|
|
}
|
|
|
|
closeOnExec(remote);
|
|
|
|
/* Get the identity of the caller, if possible. */
|
|
uid_t clientUid = -1;
|
|
pid_t clientPid = -1;
|
|
|
|
#if defined(SO_PEERCRED)
|
|
ucred cred;
|
|
socklen_t credLen = sizeof(cred);
|
|
if (getsockopt(remote, SOL_SOCKET, SO_PEERCRED, &cred, &credLen) != -1) {
|
|
clientPid = cred.pid;
|
|
clientUid = cred.uid;
|
|
}
|
|
#endif
|
|
|
|
printMsg(lvlInfo, format("accepted connection from pid %1%, uid %2%") % clientPid % clientUid);
|
|
|
|
/* Fork a child to handle the connection. */
|
|
pid_t child;
|
|
child = fork();
|
|
|
|
switch (child) {
|
|
|
|
case -1:
|
|
throw SysError("unable to fork");
|
|
|
|
case 0:
|
|
try { /* child */
|
|
|
|
/* Background the worker. */
|
|
if (setsid() == -1)
|
|
throw SysError(format("creating a new session"));
|
|
|
|
/* Restore normal handling of SIGCHLD. */
|
|
setSigChldAction(false);
|
|
|
|
/* For debugging, stuff the pid into argv[1]. */
|
|
if (clientPid != -1 && argvSaved[1]) {
|
|
string processName = int2String(clientPid);
|
|
strncpy(argvSaved[1], processName.c_str(), strlen(argvSaved[1]));
|
|
}
|
|
|
|
/* Since the daemon can be long-running, the
|
|
settings may have changed. So force a reload. */
|
|
reloadSettings();
|
|
|
|
/* Handle the connection. */
|
|
from.fd = remote;
|
|
to.fd = remote;
|
|
processConnection();
|
|
|
|
} catch (std::exception & e) {
|
|
std::cerr << format("child error: %1%\n") % e.what();
|
|
}
|
|
exit(0);
|
|
}
|
|
|
|
} catch (Interrupted & e) {
|
|
throw;
|
|
} catch (Error & e) {
|
|
printMsg(lvlError, format("error processing connection: %1%") % e.msg());
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
void run(Strings args)
|
|
{
|
|
bool slave = false;
|
|
bool daemon = false;
|
|
|
|
for (Strings::iterator i = args.begin(); i != args.end(); ) {
|
|
string arg = *i++;
|
|
if (arg == "--slave") slave = true;
|
|
if (arg == "--daemon") daemon = true;
|
|
}
|
|
|
|
if (slave) {
|
|
/* This prevents us from receiving signals from the terminal
|
|
when we're running in setuid mode. */
|
|
if (setsid() == -1)
|
|
throw SysError(format("creating a new session"));
|
|
|
|
processConnection();
|
|
}
|
|
|
|
else if (daemon) {
|
|
if (setuidMode)
|
|
throw Error("daemon cannot be started in setuid mode");
|
|
chdir("/");
|
|
daemonLoop();
|
|
}
|
|
|
|
else
|
|
throw Error("must be run in either --slave or --daemon mode");
|
|
}
|
|
|
|
|
|
#include "help.txt.hh"
|
|
|
|
void printHelp()
|
|
{
|
|
std::cout << string((char *) helpText);
|
|
}
|
|
|
|
|
|
string programId = "nix-worker";
|