From 7386caaecfd68fbf70099eb8f3a6f8e296d1fb5b Mon Sep 17 00:00:00 2001
From: John Ericson <John.Ericson@Obsidian.Systems>
Date: Mon, 22 Jan 2024 18:38:39 -0500
Subject: [PATCH] Use Nix's `SSHMaster`
---
src/hydra-queue-runner/build-remote.cc | 87 +++++++-------------------
1 file changed, 24 insertions(+), 63 deletions(-)
diff --git a/src/hydra-queue-runner/build-remote.cc b/src/hydra-queue-runner/build-remote.cc
index 68a339f3..7f547a0b 100644
--- a/src/hydra-queue-runner/build-remote.cc
+++ b/src/hydra-queue-runner/build-remote.cc
@@ -21,12 +21,6 @@
using namespace nix;
-
-static void append(Strings & dst, const Strings & src)
-{
- dst.insert(dst.end(), src.begin(), src.end());
-}
-
namespace nix::build_remote {
static Strings extraStoreArgs(std::string & machine)
@@ -49,58 +43,20 @@ static Strings extraStoreArgs(std::string & machine)
return result;
}
-static void openConnection(Machine::ptr machine, Path tmpDir, int stderrFD, SSHMaster::Connection & child)
+static std::unique_ptr<SSHMaster::Connection> openConnection(
+ Machine::ptr machine, SSHMaster & master)
{
- std::string pgmName;
- Pipe to, from;
- to.create();
- from.create();
-
- Strings argv;
+ Strings command = {"nix-store", "--serve", "--write"};
if (machine->isLocalhost()) {
- pgmName = "nix-store";
- argv = {"nix-store", "--builders", "", "--serve", "--write"};
+ command.push_back("--builders");
+ command.push_back("");
} else {
- pgmName = "ssh";
- auto sshName = machine->sshName;
- Strings extraArgs = extraStoreArgs(sshName);
- argv = {"ssh", sshName};
- if (machine->sshKey != "") append(argv, {"-i", machine->sshKey});
- if (machine->sshPublicHostKey != "") {
- Path fileName = tmpDir + "/host-key";
- auto p = machine->sshName.find("@");
- std::string host = p != std::string::npos ? std::string(machine->sshName, p + 1) : machine->sshName;
- writeFile(fileName, host + " " + machine->sshPublicHostKey + "\n");
- append(argv, {"-oUserKnownHostsFile=" + fileName});
- }
- append(argv,
- { "-x", "-a", "-oBatchMode=yes", "-oConnectTimeout=60", "-oTCPKeepAlive=yes"
- , "--", "nix-store", "--serve", "--write" });
- append(argv, extraArgs);
+ command.splice(command.end(), extraStoreArgs(machine->sshName));
}
- child.sshPid = startProcess([&]() {
- restoreProcessContext();
-
- if (dup2(to.readSide.get(), STDIN_FILENO) == -1)
- throw SysError("cannot dup input pipe to stdin");
-
- if (dup2(from.writeSide.get(), STDOUT_FILENO) == -1)
- throw SysError("cannot dup output pipe to stdout");
-
- if (dup2(stderrFD, STDERR_FILENO) == -1)
- throw SysError("cannot dup stderr");
-
- execvp(argv.front().c_str(), (char * *) stringsToCharPtrs(argv).data()); // FIXME: remove cast
-
- throw SysError("cannot start %s", pgmName);
+ return master.startCommand(std::move(command), {
+ "-a", "-oBatchMode=yes", "-oConnectTimeout=60", "-oTCPKeepAlive=yes"
});
-
- to.readSide = -1;
- from.writeSide = -1;
-
- child.in = to.writeSide.release();
- child.out = from.readSide.release();
}
@@ -430,21 +386,26 @@ void State::buildRemote(ref<Store> destStore,
AutoDelete logFileDel(logFile, false);
result.logFile = logFile;
- nix::Path tmpDir = createTempDir();
- AutoDelete tmpDirDel(tmpDir, true);
-
try {
updateStep(ssConnecting);
+ SSHMaster master {
+ machine->sshName,
+ machine->sshKey,
+ machine->sshPublicHostKey,
+ false, // no SSH master yet
+ false, // no compression yet
+ logFD.get(),
+ };
+
// FIXME: rewrite to use Store.
- SSHMaster::Connection child;
- build_remote::openConnection(machine, tmpDir, logFD.get(), child);
+ auto child = build_remote::openConnection(machine, master);
{
auto activeStepState(activeStep->state_.lock());
if (activeStepState->cancelled) throw Error("step cancelled");
- activeStepState->pid = child.sshPid;
+ activeStepState->pid = child->sshPid;
}
Finally clearPid([&]() {
@@ -461,8 +422,8 @@ void State::buildRemote(ref<Store> destStore,
Machine::Connection conn {
{
- .to = child.in.get(),
- .from = child.out.get(),
+ .to = child->in.get(),
+ .from = child->out.get(),
/* Handshake. */
.remoteVersion = 0xdadbeef, // FIXME avoid dummy initialize
},
@@ -483,7 +444,7 @@ void State::buildRemote(ref<Store> destStore,
our_version,
machine->sshName);
} catch (EndOfFile & e) {
- child.sshPid.wait();
+ child->sshPid.wait();
std::string s = chomp(readFile(result.logFile));
throw Error("cannot connect to ‘%1%’: %2%", machine->sshName, s);
}
@@ -583,8 +544,8 @@ void State::buildRemote(ref<Store> destStore,
}
/* Shut down the connection. */
- child.in = -1;
- child.sshPid.wait();
+ child->in = -1;
+ child->sshPid.wait();
} catch (Error & e) {
/* Disable this machine until a certain period of time has