Add 'third_party/nix/' from commit 'be66c7a6b24e3c3c6157fd37b86c7203d14acf10' r/724

git-subtree-dir: third_party/nix
git-subtree-mainline: cf8cd640c1adf74a3706efbcb0ea4625da106fb2
git-subtree-split: be66c7a6b24e3c3c6157fd37b86c7203d14acf10

1 files changed, 508 insertions, 0 deletions

diff --git a/third_party/nix/src/nix-build/nix-build.cc b/third_party/nix/src/nix-build/nix-build.cc
new file mode 100755
index 0000000000..33ad28704a
--- /dev/null
+++ b/third_party/nix/src/nix-build/nix-build.cc
@@ -0,0 +1,508 @@
+#include <cstring>
+#include <fstream>
+#include <iostream>
+#include <regex>
+#include <sstream>
+#include <vector>
+
+#include "store-api.hh"
+#include "globals.hh"
+#include "derivations.hh"
+#include "affinity.hh"
+#include "util.hh"
+#include "shared.hh"
+#include "eval.hh"
+#include "eval-inline.hh"
+#include "get-drvs.hh"
+#include "common-eval-args.hh"
+#include "attr-path.hh"
+#include "legacy.hh"
+
+using namespace nix;
+using namespace std::string_literals;
+
+extern char * * environ;
+
+/* Recreate the effect of the perl shellwords function, breaking up a
+ * string into arguments like a shell word, including escapes
+ */
+std::vector<string> shellwords(const string & s)
+{
+    std::regex whitespace("^(\\s+).*");
+    auto begin = s.cbegin();
+    std::vector<string> res;
+    std::string cur;
+    enum state {
+        sBegin,
+        sQuote
+    };
+    state st = sBegin;
+    auto it = begin;
+    for (; it != s.cend(); ++it) {
+        if (st == sBegin) {
+            std::smatch match;
+            if (regex_search(it, s.cend(), match, whitespace)) {
+                cur.append(begin, it);
+                res.push_back(cur);
+                cur.clear();
+                it = match[1].second;
+                begin = it;
+            }
+        }
+        switch (*it) {
+            case '"':
+                cur.append(begin, it);
+                begin = it + 1;
+                st = st == sBegin ? sQuote : sBegin;
+                break;
+            case '\\':
+                /* perl shellwords mostly just treats the next char as part of the string with no special processing */
+                cur.append(begin, it);
+                begin = ++it;
+                break;
+        }
+    }
+    cur.append(begin, it);
+    if (!cur.empty()) res.push_back(cur);
+    return res;
+}
+
+static void _main(int argc, char * * argv)
+{
+    auto dryRun = false;
+    auto runEnv = std::regex_search(argv[0], std::regex("nix-shell$"));
+    auto pure = false;
+    auto fromArgs = false;
+    auto packages = false;
+    // Same condition as bash uses for interactive shells
+    auto interactive = isatty(STDIN_FILENO) && isatty(STDERR_FILENO);
+    Strings attrPaths;
+    Strings left;
+    RepairFlag repair = NoRepair;
+    Path gcRoot;
+    BuildMode buildMode = bmNormal;
+    bool readStdin = false;
+
+    std::string envCommand; // interactive shell
+    Strings envExclude;
+
+    auto myName = runEnv ? "nix-shell" : "nix-build";
+
+    auto inShebang = false;
+    std::string script;
+    std::vector<string> savedArgs;
+
+    AutoDelete tmpDir(createTempDir("", myName));
+
+    std::string outLink = "./result";
+
+    // List of environment variables kept for --pure
+    std::set<string> keepVars{"HOME", "USER", "LOGNAME", "DISPLAY", "PATH", "TERM", "IN_NIX_SHELL", "TZ", "PAGER", "NIX_BUILD_SHELL", "SHLVL"};
+
+    Strings args;
+    for (int i = 1; i < argc; ++i)
+        args.push_back(argv[i]);
+
+    // Heuristic to see if we're invoked as a shebang script, namely,
+    // if we have at least one argument, it's the name of an
+    // executable file, and it starts with "#!".
+    if (runEnv && argc > 1 && !std::regex_search(argv[1], std::regex("nix-shell"))) {
+        script = argv[1];
+        try {
+            auto lines = tokenizeString<Strings>(readFile(script), "\n");
+            if (std::regex_search(lines.front(), std::regex("^#!"))) {
+                lines.pop_front();
+                inShebang = true;
+                for (int i = 2; i < argc; ++i)
+                    savedArgs.push_back(argv[i]);
+                args.clear();
+                for (auto line : lines) {
+                    line = chomp(line);
+                    std::smatch match;
+                    if (std::regex_match(line, match, std::regex("^#!\\s*nix-shell (.*)$")))
+                        for (const auto & word : shellwords(match[1].str()))
+                            args.push_back(word);
+                }
+            }
+        } catch (SysError &) { }
+    }
+
+    struct MyArgs : LegacyArgs, MixEvalArgs
+    {
+        using LegacyArgs::LegacyArgs;
+    };
+
+    MyArgs myArgs(myName, [&](Strings::iterator & arg, const Strings::iterator & end) {
+        if (*arg == "--help") {
+            deletePath(tmpDir);
+            showManPage(myName);
+        }
+
+        else if (*arg == "--version")
+            printVersion(myName);
+
+        else if (*arg == "--add-drv-link" || *arg == "--indirect")
+            ; // obsolete
+
+        else if (*arg == "--no-out-link" || *arg == "--no-link")
+            outLink = (Path) tmpDir + "/result";
+
+        else if (*arg == "--attr" || *arg == "-A")
+            attrPaths.push_back(getArg(*arg, arg, end));
+
+        else if (*arg == "--drv-link")
+            getArg(*arg, arg, end); // obsolete
+
+        else if (*arg == "--out-link" || *arg == "-o")
+            outLink = getArg(*arg, arg, end);
+
+        else if (*arg == "--add-root")
+            gcRoot = getArg(*arg, arg, end);
+
+        else if (*arg == "--dry-run")
+            dryRun = true;
+
+        else if (*arg == "--repair") {
+            repair = Repair;
+            buildMode = bmRepair;
+        }
+
+        else if (*arg == "--run-env") // obsolete
+            runEnv = true;
+
+        else if (*arg == "--command" || *arg == "--run") {
+            if (*arg == "--run")
+                interactive = false;
+            envCommand = getArg(*arg, arg, end) + "\nexit";
+        }
+
+        else if (*arg == "--check")
+            buildMode = bmCheck;
+
+        else if (*arg == "--exclude")
+            envExclude.push_back(getArg(*arg, arg, end));
+
+        else if (*arg == "--expr" || *arg == "-E")
+            fromArgs = true;
+
+        else if (*arg == "--pure") pure = true;
+        else if (*arg == "--impure") pure = false;
+
+        else if (*arg == "--packages" || *arg == "-p")
+            packages = true;
+
+        else if (inShebang && *arg == "-i") {
+            auto interpreter = getArg(*arg, arg, end);
+            interactive = false;
+            auto execArgs = "";
+
+            // Überhack to support Perl. Perl examines the shebang and
+            // executes it unless it contains the string "perl" or "indir",
+            // or (undocumented) argv[0] does not contain "perl". Exploit
+            // the latter by doing "exec -a".
+            if (std::regex_search(interpreter, std::regex("perl")))
+                execArgs = "-a PERL";
+
+            std::ostringstream joined;
+            for (const auto & i : savedArgs)
+                joined << shellEscape(i) << ' ';
+
+            if (std::regex_search(interpreter, std::regex("ruby"))) {
+                // Hack for Ruby. Ruby also examines the shebang. It tries to
+                // read the shebang to understand which packages to read from. Since
+                // this is handled via nix-shell -p, we wrap our ruby script execution
+                // in ruby -e 'load' which ignores the shebangs.
+                envCommand = (format("exec %1% %2% -e 'load(\"%3%\")' -- %4%") % execArgs % interpreter % script % joined.str()).str();
+            } else {
+                envCommand = (format("exec %1% %2% %3% %4%") % execArgs % interpreter % script % joined.str()).str();
+            }
+        }
+
+        else if (*arg == "--keep")
+            keepVars.insert(getArg(*arg, arg, end));
+
+        else if (*arg == "-")
+            readStdin = true;
+
+        else if (*arg != "" && arg->at(0) == '-')
+            return false;
+
+        else
+            left.push_back(*arg);
+
+        return true;
+    });
+
+    myArgs.parseCmdline(args);
+
+    initPlugins();
+
+    if (packages && fromArgs)
+        throw UsageError("'-p' and '-E' are mutually exclusive");
+
+    auto store = openStore();
+
+    auto state = std::make_unique<EvalState>(myArgs.searchPath, store);
+    state->repair = repair;
+
+    Bindings & autoArgs = *myArgs.getAutoArgs(*state);
+
+    if (packages) {
+        std::ostringstream joined;
+        joined << "with import <nixpkgs> { }; (pkgs.runCommandCC or pkgs.runCommand) \"shell\" { buildInputs = [ ";
+        for (const auto & i : left)
+            joined << '(' << i << ") ";
+        joined << "]; } \"\"";
+        fromArgs = true;
+        left = {joined.str()};
+    } else if (!fromArgs) {
+        if (left.empty() && runEnv && pathExists("shell.nix"))
+            left = {"shell.nix"};
+        if (left.empty())
+            left = {"default.nix"};
+    }
+
+    if (runEnv)
+        setenv("IN_NIX_SHELL", pure ? "pure" : "impure", 1);
+
+    DrvInfos drvs;
+
+    /* Parse the expressions. */
+    std::vector<Expr *> exprs;
+
+    if (readStdin)
+        exprs = {state->parseStdin()};
+    else
+        for (auto i : left) {
+            if (fromArgs)
+                exprs.push_back(state->parseExprFromString(i, absPath(".")));
+            else {
+                auto absolute = i;
+                try {
+                    absolute = canonPath(absPath(i), true);
+                } catch (Error & e) {};
+                if (store->isStorePath(absolute) && std::regex_match(absolute, std::regex(".*\\.drv(!.*)?")))
+                drvs.push_back(DrvInfo(*state, store, absolute));
+            else
+                /* If we're in a #! script, interpret filenames
+                   relative to the script. */
+                exprs.push_back(state->parseExprFromFile(resolveExprPath(state->checkSourcePath(lookupFileArg(*state,
+                    inShebang && !packages ? absPath(i, absPath(dirOf(script))) : i)))));
+            }
+        }
+
+    /* Evaluate them into derivations. */
+    if (attrPaths.empty()) attrPaths = {""};
+
+    for (auto e : exprs) {
+        Value vRoot;
+        state->eval(e, vRoot);
+
+        for (auto & i : attrPaths) {
+            Value & v(*findAlongAttrPath(*state, i, autoArgs, vRoot));
+            state->forceValue(v);
+            getDerivations(*state, v, "", autoArgs, drvs, false);
+        }
+    }
+
+    state->printStats();
+
+    auto buildPaths = [&](const PathSet & paths) {
+        /* Note: we do this even when !printMissing to efficiently
+           fetch binary cache data. */
+        unsigned long long downloadSize, narSize;
+        PathSet willBuild, willSubstitute, unknown;
+        store->queryMissing(paths,
+            willBuild, willSubstitute, unknown, downloadSize, narSize);
+
+        if (settings.printMissing)
+            printMissing(ref<Store>(store), willBuild, willSubstitute, unknown, downloadSize, narSize);
+
+        if (!dryRun)
+            store->buildPaths(paths, buildMode);
+    };
+
+    if (runEnv) {
+        if (drvs.size() != 1)
+            throw UsageError("nix-shell requires a single derivation");
+
+        auto & drvInfo = drvs.front();
+        auto drv = store->derivationFromPath(drvInfo.queryDrvPath());
+
+        PathSet pathsToBuild;
+
+        /* Figure out what bash shell to use. If $NIX_BUILD_SHELL
+           is not set, then build bashInteractive from
+           <nixpkgs>. */
+        auto shell = getEnv("NIX_BUILD_SHELL", "");
+
+        if (shell == "") {
+
+            try {
+                auto expr = state->parseExprFromString("(import <nixpkgs> {}).bashInteractive", absPath("."));
+
+                Value v;
+                state->eval(expr, v);
+
+                auto drv = getDerivation(*state, v, false);
+                if (!drv)
+                    throw Error("the 'bashInteractive' attribute in <nixpkgs> did not evaluate to a derivation");
+
+                pathsToBuild.insert(drv->queryDrvPath());
+
+                shell = drv->queryOutPath() + "/bin/bash";
+
+            } catch (Error & e) {
+                printError("warning: %s; will use bash from your environment", e.what());
+                shell = "bash";
+            }
+        }
+
+        // Build or fetch all dependencies of the derivation.
+        for (const auto & input : drv.inputDrvs)
+            if (std::all_of(envExclude.cbegin(), envExclude.cend(), [&](const string & exclude) { return !std::regex_search(input.first, std::regex(exclude)); }))
+                pathsToBuild.insert(makeDrvPathWithOutputs(input.first, input.second));
+        for (const auto & src : drv.inputSrcs)
+            pathsToBuild.insert(src);
+
+        buildPaths(pathsToBuild);
+
+        if (dryRun) return;
+
+        // Set the environment.
+        auto env = getEnv();
+
+        auto tmp = getEnv("TMPDIR", getEnv("XDG_RUNTIME_DIR", "/tmp"));
+
+        if (pure) {
+            decltype(env) newEnv;
+            for (auto & i : env)
+                if (keepVars.count(i.first))
+                    newEnv.emplace(i);
+            env = newEnv;
+            // NixOS hack: prevent /etc/bashrc from sourcing /etc/profile.
+            env["__ETC_PROFILE_SOURCED"] = "1";
+        }
+
+        env["NIX_BUILD_TOP"] = env["TMPDIR"] = env["TEMPDIR"] = env["TMP"] = env["TEMP"] = tmp;
+        env["NIX_STORE"] = store->storeDir;
+        env["NIX_BUILD_CORES"] = std::to_string(settings.buildCores);
+
+        auto passAsFile = tokenizeString<StringSet>(get(drv.env, "passAsFile", ""));
+
+        bool keepTmp = false;
+        int fileNr = 0;
+
+        for (auto & var : drv.env)
+            if (passAsFile.count(var.first)) {
+                keepTmp = true;
+                string fn = ".attr-" + std::to_string(fileNr++);
+                Path p = (Path) tmpDir + "/" + fn;
+                writeFile(p, var.second);
+                env[var.first + "Path"] = p;
+            } else
+                env[var.first] = var.second;
+
+        restoreAffinity();
+
+        /* Run a shell using the derivation's environment.  For
+           convenience, source $stdenv/setup to setup additional
+           environment variables and shell functions.  Also don't
+           lose the current $PATH directories. */
+        auto rcfile = (Path) tmpDir + "/rc";
+        writeFile(rcfile, fmt(
+                (keepTmp ? "" : "rm -rf '%1%'; "s) +
+                "[ -n \"$PS1\" ] && [ -e ~/.bashrc ] && source ~/.bashrc; "
+                "%2%"
+                "dontAddDisableDepTrack=1; "
+                "[ -e $stdenv/setup ] && source $stdenv/setup; "
+                "%3%"
+                "PATH=\"%4%:$PATH\"; "
+                "SHELL=%5%; "
+                "set +e; "
+                R"s([ -n "$PS1" ] && PS1='\n\[\033[1;32m\][nix-shell:\w]\$\[\033[0m\] '; )s"
+                "if [ \"$(type -t runHook)\" = function ]; then runHook shellHook; fi; "
+                "unset NIX_ENFORCE_PURITY; "
+                "shopt -u nullglob; "
+                "unset TZ; %6%"
+                "%7%",
+                (Path) tmpDir,
+                (pure ? "" : "p=$PATH; "),
+                (pure ? "" : "PATH=$PATH:$p; unset p; "),
+                dirOf(shell),
+                shell,
+                (getenv("TZ") ? (string("export TZ='") + getenv("TZ") + "'; ") : ""),
+                envCommand));
+
+        Strings envStrs;
+        for (auto & i : env)
+            envStrs.push_back(i.first + "=" + i.second);
+
+        auto args = interactive
+            ? Strings{"bash", "--rcfile", rcfile}
+            : Strings{"bash", rcfile};
+
+        auto envPtrs = stringsToCharPtrs(envStrs);
+
+        environ = envPtrs.data();
+
+        auto argPtrs = stringsToCharPtrs(args);
+
+        restoreSignals();
+
+        execvp(shell.c_str(), argPtrs.data());
+
+        throw SysError("executing shell '%s'", shell);
+    }
+
+    else {
+
+        PathSet pathsToBuild;
+
+        std::map<Path, Path> drvPrefixes;
+        std::map<Path, Path> resultSymlinks;
+        std::vector<Path> outPaths;
+
+        for (auto & drvInfo : drvs) {
+            auto drvPath = drvInfo.queryDrvPath();
+            auto outPath = drvInfo.queryOutPath();
+
+            auto outputName = drvInfo.queryOutputName();
+            if (outputName == "")
+                throw Error("derivation '%s' lacks an 'outputName' attribute", drvPath);
+
+            pathsToBuild.insert(drvPath + "!" + outputName);
+
+            std::string drvPrefix;
+            auto i = drvPrefixes.find(drvPath);
+            if (i != drvPrefixes.end())
+                drvPrefix = i->second;
+            else {
+                drvPrefix = outLink;
+                if (drvPrefixes.size())
+                    drvPrefix += fmt("-%d", drvPrefixes.size() + 1);
+                drvPrefixes[drvPath] = drvPrefix;
+            }
+
+            std::string symlink = drvPrefix;
+            if (outputName != "out") symlink += "-" + outputName;
+
+            resultSymlinks[symlink] = outPath;
+            outPaths.push_back(outPath);
+        }
+
+        buildPaths(pathsToBuild);
+
+        if (dryRun) return;
+
+        for (auto & symlink : resultSymlinks)
+            if (auto store2 = store.dynamic_pointer_cast<LocalFSStore>())
+                store2->addPermRoot(symlink.second, absPath(symlink.first), true);
+
+        for (auto & path : outPaths)
+            std::cout << path << '\n';
+    }
+}
+
+static RegisterLegacyCommand s1("nix-build", _main);
+static RegisterLegacyCommand s2("nix-shell", _main);