From 79c6614f58a57b985daf8940766319e440311db0 Mon Sep 17 00:00:00 2001 From: Ludovic Courtès Date: Tue, 1 Dec 2020 15:01:40 +0100 Subject: daemon: Use 'Agent' to spawn 'guix substitute --query'. * nix/libstore/local-store.hh (RunningSubstituter): Remove. (LocalStore)[runningSubstituter]: Change to unique_ptr. [setSubstituterEnv, didSetSubstituterEnv]: Remove. [getLineFromSubstituter, getIntLineFromSubstituter]: Take an 'Agent'. * nix/libstore/local-store.cc (LocalStore::~LocalStore): Remove reference to 'runningSubstituter'. (LocalStore::setSubstituterEnv, LocalStore::startSubstituter): Remove. (LocalStore::getLineFromSubstituter): Adjust to 'run' being an 'Agent'. (LocalStore::querySubstitutablePaths): Spawn substituter agent if needed. Adjust to 'Agent' interface. (LocalStore::querySubstitutablePathInfos): Likewise. * nix/libstore/build.cc (SubstitutionGoal::tryToRun): Remove call to 'setSubstituterEnv' and add 'setenv' call for "_NIX_OPTIONS" instead. (SubstitutionGoal::finished): Remove 'readLine' call for 'dummy'. * guix/scripts/substitute.scm (%allow-unauthenticated-substitutes?): Remove second argument to 'make-parameter'. (process-query): Call 'warn-about-missing-authentication' when (%allow-unauthenticated-substitutes?) is #t. (guix-substitute): Wrap body in 'parameterize'. Set 'guix-warning-port' too. No longer exit when 'substitute-urls' returns the empty list. No longer print newline initially. * tests/substitute.scm (test-quit): Parameterize 'current-error-port' to account for the port changes in 'guix-substitute'. --- nix/libstore/build.cc | 6 +- nix/libstore/local-store.cc | 159 +++++++++++--------------------------------- nix/libstore/local-store.hh | 22 +----- 3 files changed, 43 insertions(+), 144 deletions(-) (limited to 'nix') diff --git a/nix/libstore/build.cc b/nix/libstore/build.cc index 8413819114..7e9ab3f39c 100644 --- a/nix/libstore/build.cc +++ b/nix/libstore/build.cc @@ -2986,8 +2986,6 @@ void SubstitutionGoal::tryToRun() if (pathExists(destPath)) deletePath(destPath); - worker.store.setSubstituterEnv(); - /* Fill in the arguments. */ Strings args; args.push_back("guix"); @@ -2999,6 +2997,9 @@ void SubstitutionGoal::tryToRun() /* Fork the substitute program. */ pid = startProcess([&]() { + /* Communicate substitute-urls & co. to 'guix substitute'. */ + setenv("_NIX_OPTIONS", settings.pack().c_str(), 1); + commonChildInit(logPipe); if (dup2(outPipe.writeSide, STDOUT_FILENO) == -1) @@ -3041,7 +3042,6 @@ void SubstitutionGoal::finished() logPipe.readSide.close(); /* Get the hash info from stdout. */ - string dummy = readLine(outPipe.readSide); string expectedHashStr = statusOk(status) ? readLine(outPipe.readSide) : ""; outPipe.readSide.close(); diff --git a/nix/libstore/local-store.cc b/nix/libstore/local-store.cc index 8c479002ec..4219573a56 100644 --- a/nix/libstore/local-store.cc +++ b/nix/libstore/local-store.cc @@ -57,7 +57,6 @@ void checkStoreNotSymlink() LocalStore::LocalStore(bool reserveSpace) - : didSetSubstituterEnv(false) { schemaPath = settings.nixDBPath + "/schema"; @@ -182,21 +181,6 @@ LocalStore::LocalStore(bool reserveSpace) LocalStore::~LocalStore() { - try { - if (runningSubstituter) { - RunningSubstituter &i = *runningSubstituter; - if (!i.disabled) { - i.to.close(); - i.from.close(); - i.error.close(); - if (i.pid != -1) - i.pid.wait(true); - } - } - } catch (...) { - ignoreException(); - } - try { if (fdTempRoots != -1) { fdTempRoots.close(); @@ -796,96 +780,31 @@ Path LocalStore::queryPathFromHashPart(const string & hashPart) }); } - -void LocalStore::setSubstituterEnv() -{ - if (didSetSubstituterEnv) return; - - /* Pass configuration options (including those overridden with - --option) to substituters. */ - setenv("_NIX_OPTIONS", settings.pack().c_str(), 1); - - didSetSubstituterEnv = true; -} - - -void LocalStore::startSubstituter(RunningSubstituter & run) -{ - if (run.disabled || run.pid != -1) return; - - debug(format("starting substituter program `%1% substitute'") - % settings.guixProgram); - - Pipe toPipe, fromPipe, errorPipe; - - toPipe.create(); - fromPipe.create(); - errorPipe.create(); - - setSubstituterEnv(); - - run.pid = startProcess([&]() { - if (dup2(toPipe.readSide, STDIN_FILENO) == -1) - throw SysError("dupping stdin"); - if (dup2(fromPipe.writeSide, STDOUT_FILENO) == -1) - throw SysError("dupping stdout"); - if (dup2(errorPipe.writeSide, STDERR_FILENO) == -1) - throw SysError("dupping stderr"); - execl(settings.guixProgram.c_str(), "guix", "substitute", "--query", NULL); - throw SysError(format("executing `%1%'") % settings.guixProgram); - }); - - run.to = toPipe.writeSide.borrow(); - run.from = run.fromBuf.fd = fromPipe.readSide.borrow(); - run.error = errorPipe.readSide.borrow(); - - toPipe.readSide.close(); - fromPipe.writeSide.close(); - errorPipe.writeSide.close(); - - /* The substituter may exit right away if it's disabled in any way - (e.g. copy-from-other-stores.pl will exit if no other stores - are configured). */ - try { - getLineFromSubstituter(run); - } catch (EndOfFile & e) { - run.to.close(); - run.from.close(); - run.error.close(); - run.disabled = true; - if (run.pid.wait(true) != 0) throw; - } -} - - /* Read a line from the substituter's stdout, while also processing its stderr. */ -string LocalStore::getLineFromSubstituter(RunningSubstituter & run) +string LocalStore::getLineFromSubstituter(Agent & run) { string res, err; - /* We might have stdout data left over from the last time. */ - if (run.fromBuf.hasData()) goto haveData; - while (1) { checkInterrupt(); fd_set fds; FD_ZERO(&fds); - FD_SET(run.from, &fds); - FD_SET(run.error, &fds); + FD_SET(run.fromAgent.readSide, &fds); + FD_SET(run.builderOut.readSide, &fds); /* Wait for data to appear on the substituter's stdout or stderr. */ - if (select(run.from > run.error ? run.from + 1 : run.error + 1, &fds, 0, 0, 0) == -1) { + if (select(std::max(run.fromAgent.readSide, run.builderOut.readSide) + 1, &fds, 0, 0, 0) == -1) { if (errno == EINTR) continue; throw SysError("waiting for input from the substituter"); } /* Completely drain stderr before dealing with stdout. */ - if (FD_ISSET(run.error, &fds)) { + if (FD_ISSET(run.builderOut.readSide, &fds)) { char buf[4096]; - ssize_t n = read(run.error, (unsigned char *) buf, sizeof(buf)); + ssize_t n = read(run.builderOut.readSide, (unsigned char *) buf, sizeof(buf)); if (n == -1) { if (errno == EINTR) continue; throw SysError("reading from substituter's stderr"); @@ -903,23 +822,20 @@ string LocalStore::getLineFromSubstituter(RunningSubstituter & run) } /* Read from stdout until we get a newline or the buffer is empty. */ - else if (run.fromBuf.hasData() || FD_ISSET(run.from, &fds)) { - haveData: - do { - unsigned char c; - run.fromBuf(&c, 1); - if (c == '\n') { - if (!err.empty()) printMsg(lvlError, "substitute: " + err); - return res; - } - res += c; - } while (run.fromBuf.hasData()); + else if (FD_ISSET(run.fromAgent.readSide, &fds)) { + unsigned char c; + readFull(run.fromAgent.readSide, (unsigned char *) &c, 1); + if (c == '\n') { + if (!err.empty()) printMsg(lvlError, "substitute: " + err); + return res; + } + res += c; } } } -template T LocalStore::getIntLineFromSubstituter(RunningSubstituter & run) +template T LocalStore::getIntLineFromSubstituter(Agent & run) { string s = getLineFromSubstituter(run); T res; @@ -935,27 +851,26 @@ PathSet LocalStore::querySubstitutablePaths(const PathSet & paths) if (!settings.useSubstitutes || paths.empty()) return res; if (!runningSubstituter) { - std::unique_ptrfresh(new RunningSubstituter); + const Strings args = { "substitute", "--query" }; + const std::map env = { { "_NIX_OPTIONS", settings.pack() } }; + std::unique_ptr fresh(new Agent(settings.guixProgram, args, env)); runningSubstituter.swap(fresh); } - RunningSubstituter & run = *runningSubstituter; - startSubstituter(run); - - if (!run.disabled) { - string s = "have "; - foreach (PathSet::const_iterator, j, paths) - if (res.find(*j) == res.end()) { s += *j; s += " "; } - writeLine(run.to, s); - while (true) { - /* FIXME: we only read stderr when an error occurs, so - substituters should only write (short) messages to - stderr when they fail. I.e. they shouldn't write debug - output. */ - Path path = getLineFromSubstituter(run); - if (path == "") break; - res.insert(path); - } + Agent & run = *runningSubstituter; + + string s = "have "; + foreach (PathSet::const_iterator, j, paths) + if (res.find(*j) == res.end()) { s += *j; s += " "; } + writeLine(run.toAgent.writeSide, s); + while (true) { + /* FIXME: we only read stderr when an error occurs, so + substituters should only write (short) messages to + stderr when they fail. I.e. they shouldn't write debug + output. */ + Path path = getLineFromSubstituter(run); + if (path == "") break; + res.insert(path); } return res; @@ -967,18 +882,18 @@ void LocalStore::querySubstitutablePathInfos(PathSet & paths, SubstitutablePathI if (!settings.useSubstitutes) return; if (!runningSubstituter) { - std::unique_ptrfresh(new RunningSubstituter); + const Strings args = { "substitute", "--query" }; + const std::map env = { { "_NIX_OPTIONS", settings.pack() } }; + std::unique_ptr fresh(new Agent(settings.guixProgram, args, env)); runningSubstituter.swap(fresh); } - RunningSubstituter & run = *runningSubstituter; - startSubstituter(run); - if (run.disabled) return; + Agent & run = *runningSubstituter; string s = "info "; foreach (PathSet::const_iterator, i, paths) if (infos.find(*i) == infos.end()) { s += *i; s += " "; } - writeLine(run.to, s); + writeLine(run.toAgent.writeSide, s); while (true) { Path path = getLineFromSubstituter(run); diff --git a/nix/libstore/local-store.hh b/nix/libstore/local-store.hh index 2e48cf03e6..57d15bac7e 100644 --- a/nix/libstore/local-store.hh +++ b/nix/libstore/local-store.hh @@ -38,21 +38,11 @@ struct OptimiseStats }; -struct RunningSubstituter -{ - Pid pid; - AutoCloseFD to, from, error; - FdSource fromBuf; - bool disabled; - RunningSubstituter() : disabled(false) { }; -}; - - class LocalStore : public StoreAPI { private: /* The currently running substituter or empty. */ - std::unique_ptr runningSubstituter; + std::unique_ptr runningSubstituter; Path linksDir; @@ -178,8 +168,6 @@ public: void markContentsGood(const Path & path); - void setSubstituterEnv(); - void createUser(const std::string & userName, uid_t userId); private: @@ -213,8 +201,6 @@ private: /* Cache for pathContentsGood(). */ std::map pathContentsGoodCache; - bool didSetSubstituterEnv; - /* The file to which we write our temporary roots. */ Path fnTempRoots; AutoCloseFD fdTempRoots; @@ -262,11 +248,9 @@ private: void removeUnusedLinks(const GCState & state); - void startSubstituter(RunningSubstituter & runningSubstituter); - - string getLineFromSubstituter(RunningSubstituter & run); + string getLineFromSubstituter(Agent & run); - template T getIntLineFromSubstituter(RunningSubstituter & run); + template T getIntLineFromSubstituter(Agent & run); Path createTempDirInStore(); -- cgit v1.2.3