diff options
Diffstat (limited to 'third_party/nix/src/build-remote/build-remote.cc')
| -rw-r--r-- | third_party/nix/src/build-remote/build-remote.cc | 266 |
1 files changed, 266 insertions, 0 deletions
diff --git a/third_party/nix/src/build-remote/build-remote.cc b/third_party/nix/src/build-remote/build-remote.cc new file mode 100644 index 0000000000..279ae62f69 --- /dev/null +++ b/third_party/nix/src/build-remote/build-remote.cc @@ -0,0 +1,266 @@ +#include <cstdlib> +#include <cstring> +#include <algorithm> +#include <set> +#include <memory> +#include <tuple> +#include <iomanip> +#if __APPLE__ +#include <sys/time.h> +#endif + +#include "machines.hh" +#include "shared.hh" +#include "pathlocks.hh" +#include "globals.hh" +#include "serialise.hh" +#include "store-api.hh" +#include "derivations.hh" +#include "local-store.hh" +#include "legacy.hh" + +using namespace nix; +using std::cin; + +static void handleAlarm(int sig) { +} + +std::string escapeUri(std::string uri) +{ + std::replace(uri.begin(), uri.end(), '/', '_'); + return uri; +} + +static string currentLoad; + +static AutoCloseFD openSlotLock(const Machine & m, unsigned long long slot) +{ + return openLockFile(fmt("%s/%s-%d", currentLoad, escapeUri(m.storeUri), slot), true); +} + +static bool allSupportedLocally(const std::set<std::string>& requiredFeatures) { + for (auto & feature : requiredFeatures) + if (!settings.systemFeatures.get().count(feature)) return false; + return true; +} + +static int _main(int argc, char * * argv) +{ + { + logger = makeJSONLogger(*logger); + + /* Ensure we don't get any SSH passphrase or host key popups. */ + unsetenv("DISPLAY"); + unsetenv("SSH_ASKPASS"); + + if (argc != 2) + throw UsageError("called without required arguments"); + + verbosity = (Verbosity) std::stoll(argv[1]); + + FdSource source(STDIN_FILENO); + + /* Read the parent's settings. */ + while (readInt(source)) { + auto name = readString(source); + auto value = readString(source); + settings.set(name, value); + } + + settings.maxBuildJobs.set("1"); // hack to make tests with local?root= work + + initPlugins(); + + auto store = openStore().cast<LocalStore>(); + + /* It would be more appropriate to use $XDG_RUNTIME_DIR, since + that gets cleared on reboot, but it wouldn't work on macOS. */ + currentLoad = store->stateDir + "/current-load"; + + std::shared_ptr<Store> sshStore; + AutoCloseFD bestSlotLock; + + auto machines = getMachines(); + debug("got %d remote builders", machines.size()); + + if (machines.empty()) { + std::cerr << "# decline-permanently\n"; + return 0; + } + + string drvPath; + string storeUri; + + while (true) { + + try { + auto s = readString(source); + if (s != "try") return 0; + } catch (EndOfFile &) { return 0; } + + auto amWilling = readInt(source); + auto neededSystem = readString(source); + source >> drvPath; + auto requiredFeatures = readStrings<std::set<std::string>>(source); + + auto canBuildLocally = amWilling + && ( neededSystem == settings.thisSystem + || settings.extraPlatforms.get().count(neededSystem) > 0) + && allSupportedLocally(requiredFeatures); + + /* Error ignored here, will be caught later */ + mkdir(currentLoad.c_str(), 0777); + + while (true) { + bestSlotLock = -1; + AutoCloseFD lock = openLockFile(currentLoad + "/main-lock", true); + lockFile(lock.get(), ltWrite, true); + + bool rightType = false; + + Machine * bestMachine = nullptr; + unsigned long long bestLoad = 0; + for (auto & m : machines) { + debug("considering building on remote machine '%s'", m.storeUri); + + if (m.enabled && std::find(m.systemTypes.begin(), + m.systemTypes.end(), + neededSystem) != m.systemTypes.end() && + m.allSupported(requiredFeatures) && + m.mandatoryMet(requiredFeatures)) { + rightType = true; + AutoCloseFD free; + unsigned long long load = 0; + for (unsigned long long slot = 0; slot < m.maxJobs; ++slot) { + auto slotLock = openSlotLock(m, slot); + if (lockFile(slotLock.get(), ltWrite, false)) { + if (!free) { + free = std::move(slotLock); + } + } else { + ++load; + } + } + if (!free) { + continue; + } + bool best = false; + if (!bestSlotLock) { + best = true; + } else if (load / m.speedFactor < bestLoad / bestMachine->speedFactor) { + best = true; + } else if (load / m.speedFactor == bestLoad / bestMachine->speedFactor) { + if (m.speedFactor > bestMachine->speedFactor) { + best = true; + } else if (m.speedFactor == bestMachine->speedFactor) { + if (load < bestLoad) { + best = true; + } + } + } + if (best) { + bestLoad = load; + bestSlotLock = std::move(free); + bestMachine = &m; + } + } + } + + if (!bestSlotLock) { + if (rightType && !canBuildLocally) + std::cerr << "# postpone\n"; + else + std::cerr << "# decline\n"; + break; + } + +#if __APPLE__ + futimes(bestSlotLock.get(), NULL); +#else + futimens(bestSlotLock.get(), NULL); +#endif + + lock = -1; + + try { + + Activity act(*logger, lvlTalkative, actUnknown, fmt("connecting to '%s'", bestMachine->storeUri)); + + Store::Params storeParams; + if (hasPrefix(bestMachine->storeUri, "ssh://")) { + storeParams["max-connections"] ="1"; + storeParams["log-fd"] = "4"; + if (bestMachine->sshKey != "") + storeParams["ssh-key"] = bestMachine->sshKey; + } + + sshStore = openStore(bestMachine->storeUri, storeParams); + sshStore->connect(); + storeUri = bestMachine->storeUri; + + } catch (std::exception & e) { + auto msg = chomp(drainFD(5, false)); + printError("cannot build on '%s': %s%s", + bestMachine->storeUri, e.what(), + (msg.empty() ? "" : ": " + msg)); + bestMachine->enabled = false; + continue; + } + + goto connected; + } + } + +connected: + close(5); + + std::cerr << "# accept\n" << storeUri << "\n"; + + auto inputs = readStrings<PathSet>(source); + auto outputs = readStrings<PathSet>(source); + + AutoCloseFD uploadLock = openLockFile(currentLoad + "/" + escapeUri(storeUri) + ".upload-lock", true); + + { + Activity act(*logger, lvlTalkative, actUnknown, fmt("waiting for the upload lock to '%s'", storeUri)); + + auto old = signal(SIGALRM, handleAlarm); + alarm(15 * 60); + if (!lockFile(uploadLock.get(), ltWrite, true)) + printError("somebody is hogging the upload lock for '%s', continuing..."); + alarm(0); + signal(SIGALRM, old); + } + + auto substitute = settings.buildersUseSubstitutes ? Substitute : NoSubstitute; + + { + Activity act(*logger, lvlTalkative, actUnknown, fmt("copying dependencies to '%s'", storeUri)); + copyPaths(store, ref<Store>(sshStore), inputs, NoRepair, NoCheckSigs, substitute); + } + + uploadLock = -1; + + BasicDerivation drv(readDerivation(store->realStoreDir + "/" + baseNameOf(drvPath))); + drv.inputSrcs = inputs; + + auto result = sshStore->buildDerivation(drvPath, drv); + + if (!result.success()) + throw Error("build of '%s' on '%s' failed: %s", drvPath, storeUri, result.errorMsg); + + PathSet missing; + for (auto & path : outputs) + if (!store->isValidPath(path)) missing.insert(path); + + if (!missing.empty()) { + Activity act(*logger, lvlTalkative, actUnknown, fmt("copying outputs from '%s'", storeUri)); + store->locksHeld.insert(missing.begin(), missing.end()); /* FIXME: ugly */ + copyPaths(ref<Store>(sshStore), store, missing, NoRepair, NoCheckSigs, NoSubstitute); + } + + return 0; + } +} + +static RegisterLegacyCommand s1("build-remote", _main); |