path: root/src/libstore/globals.hh

#pragma once

#include "types.hh"
#include "config.hh"
#include "util.hh"

#include <map>
#include <limits>

#include <sys/types.h>

namespace nix {

typedef enum { smEnabled, smRelaxed, smDisabled } SandboxMode;

struct MaxBuildJobsSetting : public BaseSetting<unsigned int>
{
    MaxBuildJobsSetting(Config * options,
        unsigned int def,
        const std::string & name,
        const std::string & description,
        const std::set<std::string> & aliases = {})
        : BaseSetting<unsigned int>(def, name, description, aliases)
    {
        options->addSetting(this);
    }

    void set(const std::string & str, bool append = false) override;
};

class Settings : public Config {

    unsigned int getDefaultCores();

    StringSet getDefaultSystemFeatures();

    bool isWSL1();

public:

    Settings();

    Path nixPrefix;

    /* The directory where we store sources and derived files. */
    Path nixStore;

    Path nixDataDir; /* !!! fix */

    /* The directory where we log various operations. */
    Path nixLogDir;

    /* The directory where state is stored. */
    Path nixStateDir;

    /* The directory where system configuration files are stored. */
    Path nixConfDir;

    /* A list of user configuration files to load. */
    std::vector<Path> nixUserConfFiles;

    /* The directory where internal helper programs are stored. */
    Path nixLibexecDir;

    /* The directory where the main programs are stored. */
    Path nixBinDir;

    /* The directory where the man pages are stored. */
    Path nixManDir;

    /* File name of the socket the daemon listens to.  */
    Path nixDaemonSocketFile;

    Setting<std::string> storeUri{this, getEnv("NIX_REMOTE").value_or("auto"), "store",
        "The default Nix store to use."};

    Setting<bool> keepFailed{this, false, "keep-failed",
        "Whether to keep temporary directories of failed builds."};

    Setting<bool> keepGoing{this, false, "keep-going",
        "Whether to keep building derivations when another build fails."};

    Setting<bool> tryFallback{
        this, false, "fallback",
        R"(
          If set to `true`, Nix will fall back to building from source if a
          binary substitute fails. This is equivalent to the `--fallback`
          flag. The default is `false`.
        )",
        {"build-fallback"}};

    /* Whether to show build log output in real time. */
    bool verboseBuild = true;

    Setting<size_t> logLines{this, 10, "log-lines",
        "If `verbose-build` is false, the number of lines of the tail of "
        "the log to show if a build fails."};

    MaxBuildJobsSetting maxBuildJobs{
        this, 1, "max-jobs",
        R"(
          This option defines the maximum number of jobs that Nix will try to
          build in parallel. The default is `1`. The special value `auto`
          causes Nix to use the number of CPUs in your system. `0` is useful
          when using remote builders to prevent any local builds (except for
          `preferLocalBuild` derivation attribute which executes locally
          regardless). It can be overridden using the `--max-jobs` (`-j`)
          command line switch.
        )",
        {"build-max-jobs"}};

    Setting<unsigned int> buildCores{
        this, getDefaultCores(), "cores",
        R"(
          Sets the value of the `NIX_BUILD_CORES` environment variable in the
          invocation of builders. Builders can use this variable at their
          discretion to control the maximum amount of parallelism. For
          instance, in Nixpkgs, if the derivation attribute
          `enableParallelBuilding` is set to `true`, the builder passes the
          `-jN` flag to GNU Make. It can be overridden using the `--cores`
          command line switch and defaults to `1`. The value `0` means that
          the builder should use all available CPU cores in the system.
        )",
        {"build-cores"}};

    /* Read-only mode.  Don't copy stuff to the store, don't change
       the database. */
    bool readOnlyMode = false;

    Setting<std::string> thisSystem{
        this, SYSTEM, "system",
        R"(
          This option specifies the canonical Nix system name of the current
          installation, such as `i686-linux` or `x86_64-darwin`. Nix can only
          build derivations whose `system` attribute equals the value
          specified here. In general, it never makes sense to modify this
          value from its default, since you can use it to ‘lie’ about the
          platform you are building on (e.g., perform a Mac OS build on a
          Linux machine; the result would obviously be wrong). It only makes
          sense if the Nix binaries can run on multiple platforms, e.g.,
          ‘universal binaries’ that run on `x86_64-linux` and `i686-linux`.

          It defaults to the canonical Nix system name detected by `configure`
          at build time.
        )"};

    Setting<time_t> maxSilentTime{
        this, 0, "max-silent-time",
        R"(
          This option defines the maximum number of seconds that a builder can
          go without producing any data on standard output or standard error.
          This is useful (for instance in an automated build system) to catch
          builds that are stuck in an infinite loop, or to catch remote builds
          that are hanging due to network problems. It can be overridden using
          the `--max-silent-time` command line switch.

          The value `0` means that there is no timeout. This is also the
          default.
        )",
        {"build-max-silent-time"}};

    Setting<time_t> buildTimeout{
        this, 0, "timeout",
        R"(
          This option defines the maximum number of seconds that a builder can
          run. This is useful (for instance in an automated build system) to
          catch builds that are stuck in an infinite loop but keep writing to
          their standard output or standard error. It can be overridden using
          the `--timeout` command line switch.

          The value `0` means that there is no timeout. This is also the
          default.
        )",
        {"build-timeout"}};

    PathSetting buildHook{this, true, nixLibexecDir + "/nix/build-remote", "build-hook",
        "The path of the helper program that executes builds to remote machines."};

    Setting<std::string> builders{
        this, "@" + nixConfDir + "/machines", "builders",
        "A semicolon-separated list of build machines, in the format of `nix.machines`."};

    Setting<bool> buildersUseSubstitutes{
        this, false, "builders-use-substitutes",
        R"(
          If set to `true`, Nix will instruct remote build machines to use
          their own binary substitutes if available. In practical terms, this
          means that remote hosts will fetch as many build dependencies as
          possible from their own substitutes (e.g, from `cache.nixos.org`),
          instead of waiting for this host to upload them all. This can
          drastically reduce build times if the network connection between
          this computer and the remote build host is slow.
        )"};

    Setting<off_t> reservedSize{this, 8 * 1024 * 1024, "gc-reserved-space",
        "Amount of reserved disk space for the garbage collector."};

    Setting<bool> fsyncMetadata{
        this, true, "fsync-metadata",
        R"(