diff options
Diffstat (limited to 'src/build-remote/build-remote.cc')
| -rw-r--r-- | src/build-remote/build-remote.cc | 276 |
1 files changed, 276 insertions, 0 deletions
diff --git a/src/build-remote/build-remote.cc b/src/build-remote/build-remote.cc new file mode 100644 index 000000000..98ccc3ddc --- /dev/null +++ b/src/build-remote/build-remote.cc @@ -0,0 +1,276 @@ +#include <cstdlib> +#include <cstring> +#include <algorithm> +#include <set> +#include <memory> +#include <tuple> +#include <iomanip> + +#include "shared.hh" +#include "pathlocks.hh" +#include "globals.hh" +#include "serve-protocol.hh" +#include "serialise.hh" +#include "store-api.hh" +#include "derivations.hh" + +using namespace nix; +using std::cerr; +using std::cin; + +static void handle_alarm(int sig) { +} + +class machine { + const std::set<string> supportedFeatures; + const std::set<string> mandatoryFeatures; + +public: + const string hostName; + const std::vector<string> systemTypes; + const string sshKey; + const unsigned long long maxJobs; + const unsigned long long speedFactor; + bool enabled; + + bool allSupported(const std::set<string> & features) const { + return std::all_of(features.begin(), features.end(), + [&](const string & feature) { + return supportedFeatures.count(feature) || + mandatoryFeatures.count(feature); + }); + } + + bool mandatoryMet(const std::set<string> & features) const { + return std::all_of(mandatoryFeatures.begin(), mandatoryFeatures.end(), + [&](const string & feature) { + return features.count(feature); + }); + } + + machine(decltype(hostName) hostName, + decltype(systemTypes) systemTypes, + decltype(sshKey) sshKey, + decltype(maxJobs) maxJobs, + decltype(speedFactor) speedFactor, + decltype(supportedFeatures) supportedFeatures, + decltype(mandatoryFeatures) mandatoryFeatures) : + supportedFeatures{std::move(supportedFeatures)}, + mandatoryFeatures{std::move(mandatoryFeatures)}, + hostName{std::move(hostName)}, + systemTypes{std::move(systemTypes)}, + sshKey{std::move(sshKey)}, + maxJobs{std::move(maxJobs)}, + speedFactor{speedFactor == 0 ? 1 : std::move(speedFactor)}, + enabled{true} {}; +};; + +static std::vector<machine> read_conf() { + auto conf = getEnv("NIX_REMOTE_SYSTEMS", SYSCONFDIR "/nix/machines"); + + auto machines = std::vector<machine>{}; + auto lines = std::vector<string>{}; + try { + lines = tokenizeString<std::vector<string>>(readFile(conf), "\n"); + } catch (const SysError & e) { + if (e.errNo != ENOENT) + throw; + } + for (auto line : lines) { + chomp(line); + line.erase(std::find(line.begin(), line.end(), '#'), line.end()); + if (line.empty()) { + continue; + } + auto tokens = tokenizeString<std::vector<string>>(line); + auto sz = tokens.size(); + if (sz < 4) { + throw new FormatError(format("Bad machines.conf file %1%") + % conf); + } + machines.emplace_back(tokens[0], + tokenizeString<std::vector<string>>(tokens[1], ","), + tokens[2], + stoull(tokens[3]), + sz >= 5 ? stoull(tokens[4]) : 1LL, + sz >= 6 ? + tokenizeString<std::set<string>>(tokens[5], ",") : + std::set<string>{}, + sz >= 7 ? + tokenizeString<std::set<string>>(tokens[6], ",") : + std::set<string>{}); + } + return machines; +} + +static string currentLoad; + +static int openSlotLock(const machine & m, unsigned long long slot) { + auto fn_stream = std::stringstream(currentLoad, std::ios_base::ate | std::ios_base::out); + fn_stream << "/"; + for (auto t : m.systemTypes) { + fn_stream << t << "-"; + } + fn_stream << m.hostName << "-" << slot; + return openLockFile(fn_stream.str(), true); +} + +static char display_env[] = "DISPLAY="; +static char ssh_env[] = "SSH_ASKPASS="; + +int main (int argc, char * * argv) +{ + return handleExceptions(argv[0], [&]() { + initNix(); + /* Ensure we don't get any SSH passphrase or host key popups. */ + if (putenv(display_env) == -1 || + putenv(ssh_env) == -1) { + throw SysError("Setting SSH env vars"); + } + + if (argc != 4) { + throw UsageError("called without required arguments"); + } + + auto store = openStore(); + + auto localSystem = argv[1]; + settings.maxSilentTime = stoull(string(argv[2])); + settings.buildTimeout = stoull(string(argv[3])); + + currentLoad = getEnv("NIX_CURRENT_LOAD", "/run/nix/current-load"); + + std::shared_ptr<Store> sshStore; + AutoCloseFD bestSlotLock; + + auto machines = read_conf(); + string drvPath; + string hostName; + for (string line; getline(cin, line);) { + auto tokens = tokenizeString<std::vector<string>>(line); + auto sz = tokens.size(); + if (sz != 3 && sz != 4) { + throw Error(format("invalid build hook line %1%") % line); + } + auto amWilling = tokens[0] == "1"; + auto neededSystem = tokens[1]; + drvPath = tokens[2]; + auto requiredFeatures = sz == 3 ? + std::set<string>{} : + tokenizeString<std::set<string>>(tokens[3], ","); + auto canBuildLocally = amWilling && (neededSystem == localSystem); + + /* 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) { + 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) { + AutoCloseFD 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) { + cerr << "# postpone\n"; + } else { + cerr << "# decline\n"; + } + break; + } + + futimens(bestSlotLock.get(), NULL); + + lock = -1; + + try { + sshStore = openStore("ssh://" + bestMachine->hostName + "?key=" + bestMachine->sshKey); + hostName = bestMachine->hostName; + } catch (std::exception & e) { + cerr << e.what() << '\n'; + cerr << "unable to open SSH connection to ‘" << bestMachine->hostName << "’, trying other available machines...\n"; + bestMachine->enabled = false; + continue; + } + goto connected; + } + } +connected: + cerr << "# accept\n"; + string line; + if (!getline(cin, line)) { + throw Error("hook caller didn't send inputs"); + } + auto inputs = tokenizeString<std::list<string>>(line); + if (!getline(cin, line)) { + throw Error("hook caller didn't send outputs"); + } + auto outputs = tokenizeString<Strings>(line); + AutoCloseFD uploadLock = openLockFile(currentLoad + "/" + hostName + ".upload-lock", true); + auto old = signal(SIGALRM, handle_alarm); + alarm(15 * 60); + if (!lockFile(uploadLock.get(), ltWrite, true)) { + cerr << "somebody is hogging the upload lock for " << hostName << ", continuing...\n"; + } + alarm(0); + signal(SIGALRM, old); + copyPaths(store, ref<Store>(sshStore), inputs); + uploadLock = -1; + + cerr << "building ‘" << drvPath << "’ on ‘" << hostName << "’\n"; + sshStore->buildDerivation(drvPath, readDerivation(drvPath)); + + std::remove_if(outputs.begin(), outputs.end(), [=](const Path & path) { return store->isValidPath(path); }); + if (!outputs.empty()) { + setenv("NIX_HELD_LOCKS", concatStringsSep(" ", outputs).c_str(), 1); /* FIXME: ugly */ + copyPaths(ref<Store>(sshStore), store, outputs); + } + return; + }); +} |