From d3176ce076407ef3e63667c0436bccf8be317ae4 Mon Sep 17 00:00:00 2001 From: Eelco Dolstra Date: Wed, 22 Jun 2022 22:43:53 +0200 Subject: [PATCH] Fix build-remote in nix-static 'build-remote' is now executed via /proc/self/exe so it always works. --- src/libstore/build/hook-instance.cc | 25 ++++++++++++++++++------- src/libstore/globals.cc | 5 +++-- src/libstore/globals.hh | 2 +- src/libutil/util.cc | 14 ++++++++++++++ src/libutil/util.hh | 6 +++++- src/nix/main.cc | 5 +++++ src/nix/run.cc | 2 +- 7 files changed, 47 insertions(+), 12 deletions(-) diff --git a/src/libstore/build/hook-instance.cc b/src/libstore/build/hook-instance.cc index 0f6f580be..1f19ddccc 100644 --- a/src/libstore/build/hook-instance.cc +++ b/src/libstore/build/hook-instance.cc @@ -7,6 +7,22 @@ HookInstance::HookInstance() { debug("starting build hook '%s'", settings.buildHook); + auto buildHookArgs = tokenizeString>(settings.buildHook.get()); + + if (buildHookArgs.empty()) + throw Error("'build-hook' setting is empty"); + + auto buildHook = buildHookArgs.front(); + buildHookArgs.pop_front(); + + Strings args; + + for (auto & arg : buildHookArgs) + args.push_back(arg); + + args.push_back(std::string(baseNameOf(settings.buildHook.get()))); + args.push_back(std::to_string(verbosity)); + /* Create a pipe to get the output of the child. */ fromHook.create(); @@ -36,14 +52,9 @@ HookInstance::HookInstance() if (dup2(builderOut.readSide.get(), 5) == -1) throw SysError("dupping builder's stdout/stderr"); - Strings args = { - std::string(baseNameOf(settings.buildHook.get())), - std::to_string(verbosity), - }; + execv(buildHook.c_str(), stringsToCharPtrs(args).data()); - execv(settings.buildHook.get().c_str(), stringsToCharPtrs(args).data()); - - throw SysError("executing '%s'", settings.buildHook); + throw SysError("executing '%s'", buildHook); }); pid.setSeparatePG(true); diff --git a/src/libstore/globals.cc b/src/libstore/globals.cc index cc009a026..1d7f65135 100644 --- a/src/libstore/globals.cc +++ b/src/libstore/globals.cc @@ -67,12 +67,13 @@ Settings::Settings() sandboxPaths = tokenizeString("/bin/sh=" SANDBOX_SHELL); #endif - -/* chroot-like behavior from Apple's sandbox */ + /* chroot-like behavior from Apple's sandbox */ #if __APPLE__ sandboxPaths = tokenizeString("/System/Library/Frameworks /System/Library/PrivateFrameworks /bin/sh /bin/bash /private/tmp /private/var/tmp /usr/lib"); allowedImpureHostPrefixes = tokenizeString("/System/Library /usr/lib /dev /bin/sh"); #endif + + buildHook = getSelfExe().value_or("nix") + " __build-remote"; } void loadConfFile() diff --git a/src/libstore/globals.hh b/src/libstore/globals.hh index 0ee27ecb6..9df1c999c 100644 --- a/src/libstore/globals.hh +++ b/src/libstore/globals.hh @@ -195,7 +195,7 @@ public: )", {"build-timeout"}}; - PathSetting buildHook{this, true, nixLibexecDir + "/nix/build-remote", "build-hook", + PathSetting buildHook{this, true, "", "build-hook", "The path of the helper program that executes builds to remote machines."}; Setting builders{ diff --git a/src/libutil/util.cc b/src/libutil/util.cc index aabd23427..82628461c 100644 --- a/src/libutil/util.cc +++ b/src/libutil/util.cc @@ -633,6 +633,20 @@ Path getDataDir() } +std::optional getSelfExe() +{ + static std::optional cached = []() + { + #if __linux__ + return readLink("/proc/self/exe"); + #else + return std::nullopt; + #endif + }(); + return cached; +} + + Paths createDirs(const Path & path) { Paths created; diff --git a/src/libutil/util.hh b/src/libutil/util.hh index 90418b04d..d3ed15b0b 100644 --- a/src/libutil/util.hh +++ b/src/libutil/util.hh @@ -149,10 +149,14 @@ std::vector getConfigDirs(); /* Return $XDG_DATA_HOME or $HOME/.local/share. */ Path getDataDir(); +/* Return the path of the current executable. */ +std::optional getSelfExe(); + /* Create a directory and all its parents, if necessary. Returns the list of created directories, in order of creation. */ Paths createDirs(const Path & path); -inline Paths createDirs(PathView path) { +inline Paths createDirs(PathView path) +{ return createDirs(Path(path)); } diff --git a/src/nix/main.cc b/src/nix/main.cc index f398e3118..17c92ebc6 100644 --- a/src/nix/main.cc +++ b/src/nix/main.cc @@ -266,6 +266,11 @@ void mainWrapped(int argc, char * * argv) programPath = argv[0]; auto programName = std::string(baseNameOf(programPath)); + if (argc > 0 && std::string_view(argv[0]) == "__build-remote") { + programName = "build-remote"; + argv++; argc--; + } + { auto legacy = (*RegisterLegacyCommand::commands)[programName]; if (legacy) return legacy(argc, argv); diff --git a/src/nix/run.cc b/src/nix/run.cc index 25a8fa8d3..45d2dfd0d 100644 --- a/src/nix/run.cc +++ b/src/nix/run.cc @@ -47,7 +47,7 @@ void runProgramInStore(ref store, Strings helperArgs = { chrootHelperName, store->storeDir, store2->getRealStoreDir(), program }; for (auto & arg : args) helperArgs.push_back(arg); - execv(readLink("/proc/self/exe").c_str(), stringsToCharPtrs(helperArgs).data()); + execv(getSelfExe().value_or("nix").c_str(), stringsToCharPtrs(helperArgs).data()); throw SysError("could not execute chroot helper"); }