guix-devel/nix/libstore/globals.hh

#pragma once

#include "config.h"
#include "types.hh"

#include <map>
#include <sys/types.h>


namespace nix {

enum CompressionType
{
    COMPRESSION_NONE = 0,
    COMPRESSION_GZIP = 1
#if HAVE_BZLIB_H
    , COMPRESSION_BZIP2 = 2
#endif
};

struct Settings {

    typedef std::map<string, string> SettingsMap;

    Settings();

    void processEnvironment();

    void set(const string & name, const string & value);

    string get(const string & name, const string & def);

    Strings get(const string & name, const Strings & def);

    bool get(const string & name, bool def);

    int get(const string & name, int def);

    void update();

    string pack();

    SettingsMap getOverrides();

    /* 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 we keep the SQLite database. */
    Path nixDBPath;

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

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

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

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

    /* Whether to keep temporary directories of failed builds. */
    bool keepFailed;

    /* Whether to keep building subgoals when a sibling (another
       subgoal of the same goal) fails. */
    bool keepGoing;

    /* User and groud id of the client issuing the build request.  Used to set
       the owner and group of the kept temporary directories of failed
       builds. */
    uid_t clientUid;
    gid_t clientGid;

    /* Whether, if we cannot realise the known closure corresponding
       to a derivation, we should try to normalise the derivation
       instead. */
    bool tryFallback;

    /* Verbosity level for build output. */
    Verbosity buildVerbosity;

    /* Maximum number of parallel build jobs.  0 means unlimited. */
    unsigned int maxBuildJobs;

    /* Number of CPU cores to utilize in parallel within a build,
       i.e. by passing this number to Make via '-j'. 0 means that the
       number of actual CPU cores on the local host ought to be
       auto-detected. */
    unsigned int buildCores;

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

    /* The canonical system name, as returned by config.guess. */
    string thisSystem;

    /* The maximum time in seconds that a builer can go without
       producing any output on stdout/stderr before it is killed.  0
       means infinity. */
    time_t maxSilentTime;

    /* The maximum duration in seconds that a builder can run.  0
       means infinity.  */
    time_t buildTimeout;

    /* The substituters.  There are programs that can somehow realise
       a store path without building, e.g., by downloading it or
       copying it from a CD. */
    Paths substituters;

    /* Whether to use build hooks (for distributed builds).  Sometimes
       users want to disable this from the command-line. */
    bool useBuildHook;

    /* Whether buildDerivations() should print out lines on stderr in
       a fixed format to allow its progress to be monitored.  Each
       line starts with a "@".  The following are defined:

       @ build-started <drvpath> <outpath> <system> <logfile>
       @ build-failed <drvpath> <outpath> <exitcode> <error text>
       @ build-succeeded <drvpath> <outpath>
       @ substituter-started <outpath> <substituter>
       @ substituter-failed <outpath> <exitcode> <error text>
       @ substituter-succeeded <outpath>

       Best combined with --no-build-output, otherwise stderr might
       conceivably contain lines in this format printed by the
       builders. */
    bool printBuildTrace;

    /* Amount of reserved space for the garbage collector
       (/nix/var/nix/db/reserved). */
    off_t reservedSize;

    /* Whether SQLite should use fsync. */
    bool fsyncMetadata;

    /* Whether SQLite should use WAL mode. */
    bool useSQLiteWAL;

    /* Whether to call sync() before registering a path as valid. */
    bool syncBeforeRegistering;

    /* Whether to use substitutes. */
    bool useSubstitutes;

    /* The Unix group that contains the build users. */
    string buildUsersGroup;

    /* Whether to build in chroot. */
    bool useChroot;

    /* Whether to impersonate a Linux 2.6 machine on newer kernels. */
    bool impersonateLinux26;

    /* Whether to store build logs. */
    bool keepLog;

    /* Whether to compress logs. */
    enum CompressionType logCompression;

    /* Maximum number of bytes a builder can write to stdout/stderr
       before being killed (0 means no limit). */
    unsigned long maxLogSize;

    /* Whether to cache build failures. */
    bool cacheFailure;

    /* How often (in seconds) to poll for locks. */
    unsigned int pollInterval;

    /* Whether to check if new GC roots can in fact be found by the
       garbage collector. */
    bool checkRootReachability;

    /* Whether the garbage collector should keep outputs of live
       derivations. */
    bool gcKeepOutputs;

    /* Whether the garbage collector should keep derivers of live
       paths. */
    bool gcKeepDerivations;

    /* Whether to automatically replace files with identical contents
       with hard links. */
    bool autoOptimiseStore;

    /* Whether to add derivations as a dependency of user environments
       (to prevent them from being GCed). */
    bool envKeepDerivations;

    /* Whether to lock the Nix client and worker to the same CPU. */
    bool lockCPU;

    /* Whether to show a stack trace if Nix evaluation fails. */
    bool showTrace;

private:
    SettingsMap settings, overrides;

    void _get(string & res, const string & name);
    void _get(bool & res, const string & name);
    void _get(StringSet & res, const string & name);
    void _get(Strings & res, const string & name);
    template<class N> void _get(N & res, const string & name);
};


// FIXME: don't use a global variable.
extern Settings settings;


extern const string nixVersion;


}