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#include "shared.hh"
#include "util.hh"
#include "serialise.hh"
#include "archive.hh"
#include "affinity.hh"
#include "globals.hh"
#include "serve-protocol.hh"
#include <iostream>
#include <unistd.h>
using namespace nix;
using std::pair;
using std::cout;
using std::endl;
// !!! TODO:
// * Respect more than the first host
// * use a database
// * show progress
static pair<FdSink, FdSource> connect(string conn) {
Pipe to, from;
to.create();
from.create();
pid_t child = fork();
switch (child) {
case -1:
throw SysError("unable to fork");
case 0:
try {
restoreAffinity();
if (dup2(to.readSide, STDIN_FILENO) == -1)
throw SysError("dupping stdin");
if (dup2(from.writeSide, STDOUT_FILENO) == -1)
throw SysError("dupping stdout");
execlp("ssh"
, "ssh"
, "-x"
, "-T"
, conn.c_str()
, "nix-store --serve"
, NULL);
throw SysError("executing ssh");
} catch (std::exception & e) {
std::cerr << "error: " << e.what() << std::endl;
}
_exit(1);
}
// If child exits unexpectedly, we'll EPIPE or EOF early.
// If we exit unexpectedly, child will EPIPE or EOF early.
// So no need to keep track of it.
return pair<FdSink, FdSource>(to.writeSide.borrow(), from.readSide.borrow());
}
static void substitute(pair<FdSink, FdSource> & pipes, Path storePath, Path destPath) {
writeInt(cmdSubstitute, pipes.first);
writeString(storePath, pipes.first);
pipes.first.flush();
restorePath(destPath, pipes.second);
cout << endl;
}
static void query(pair<FdSink, FdSource> & pipes) {
using std::cin;
writeInt(cmdQuery, pipes.first);
for (string line; getline(cin, line);) {
Strings tokenized = tokenizeString<Strings>(line);
string cmd = tokenized.front();
tokenized.pop_front();
if (cmd == "have") {
writeInt(qCmdHave, pipes.first);
foreach (Strings::iterator, i, tokenized)
writeStrings(tokenized, pipes.first);
pipes.first.flush();
PathSet paths = readStrings<PathSet>(pipes.second);
foreach (PathSet::iterator, i, paths)
cout << *i << endl;
} else if (cmd == "info") {
writeInt(qCmdInfo, pipes.first);
foreach (Strings::iterator, i, tokenized)
writeStrings(tokenized, pipes.first);
pipes.first.flush();
for (Path path = readString(pipes.second); !path.empty(); path = readString(pipes.second)) {
cout << path << endl;
cout << readString(pipes.second) << endl;
PathSet references = readStrings<PathSet>(pipes.second);
cout << references.size() << endl;
foreach (PathSet::iterator, i, references)
cout << *i << endl;
cout << readLongLong(pipes.second) << endl;
cout << readLongLong(pipes.second) << endl;
}
} else
throw Error(format("Unknown substituter query `%1%'") % cmd);
cout << endl;
}
}
void run(Strings args)
{
if (args.empty())
throw UsageError("download-via-ssh requires an argument");
if (settings.sshSubstituterHosts.empty())
return;
cout << endl;
pair<FdSink, FdSource> pipes = connect(settings.sshSubstituterHosts.front());
/* Exchange the greeting */
writeInt(SERVE_MAGIC_1, pipes.first);
pipes.first.flush();
unsigned int magic = readInt(pipes.second);
if (magic != SERVE_MAGIC_2)
throw Error("protocol mismatch");
readInt(pipes.second); // Server version, unused for now
writeInt(SERVE_PROTOCOL_VERSION, pipes.first);
pipes.first.flush();
Strings::iterator i = args.begin();
if (*i == "--query")
query(pipes);
else if (*i == "--substitute")
if (args.size() != 3)
throw UsageError("download-via-ssh: --substitute takes exactly two arguments");
else {
Path storePath = *++i;
Path destPath = *++i;
substitute(pipes, storePath, destPath);
}
else
throw UsageError(format("download-via-ssh: unknown command `%1%'") % *i);
}
void printHelp()
{
std::cerr << "Usage: download-via-ssh --query|--substitute store-path dest-path" << std::endl;
}
string programId = "download-via-ssh";
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