Explicitly model all settings and fail on unrecognized ones

Previously, the Settings class allowed other code to query for string
properties, which led to a proliferation of code all over the place making
up new options without any sort of central registry of valid options. This
commit pulls all those options back into the central Settings class and
removes the public get() methods, to discourage future abuses like that.

Furthermore, because we know the full set of options ahead of time, we
now fail loudly if someone enters an unrecognized option, thus preventing
subtle typos. With some template fun, we could probably also dump the full
set of options (with documentation, defaults, etc.) to the command line,
but I'm not doing that yet here.

1 files changed, 78 insertions, 8 deletions

diff --git a/src/libstore/globals.hh b/src/libstore/globals.hh
index 0ff18f8b16ea..d74488a41b30 100644
--- a/src/libstore/globals.hh
+++ b/src/libstore/globals.hh
@@ -20,14 +20,6 @@ struct Settings {
 
     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();
@@ -36,6 +28,10 @@ struct Settings {
 
     SettingsMap getOverrides();
 
+    /* TODO: the comments below should be strings and exposed via a nice command-line UI or similar.
+       We should probably replace it with some sort of magic template or macro to minimize the amount
+       of duplication and pain here. */
+
     /* The directory where we store sources and derived files. */
     Path nixStore;
 
@@ -187,6 +183,75 @@ struct Settings {
     /* Whether the importNative primop should be enabled */
     bool enableImportNative;
 
+    /* Whether to enable sandboxed builds (string until we get an enum for true/false/relaxed) */
+    string useSandbox;
+
+    /* The basic set of paths to expose in a sandbox */
+    PathSet sandboxPaths;
+
+    /* Any extra sandbox paths to expose */
+    PathSet extraSandboxPaths;
+
+    /* Whether to allow certain questionable operations (like fetching) during evaluation */
+    bool restrictEval;
+
+    /* The number of times to repeat a build to check for determinism */
+    int buildRepeat;
+
+    /* Which prefixes to allow derivations to ask for access to (primarily for Darwin) */
+    PathSet allowedImpureHostPrefixes;
+
+    /* The size of /dev/shm in the build sandbox (for Linux) */
+    string sandboxShmSize;
+
+    /* Whether to log Darwin sandbox access violations to the system log */
+    bool darwinLogSandboxViolations;
+
+    /* ??? */
+    bool runDiffHook;
+
+    /* ??? */
+    string diffHook;
+
+    /* Whether to fail if repeated builds produce different output */
+    bool enforceDeterminism;
+
+    /* The known public keys for a binary cache */
+    Strings binaryCachePublicKeys;
+
+    /* Secret keys to use for build output signing */
+    Strings secretKeyFiles;
+
+    /* Number of parallel connections to hit a binary cache with when finding out if it contains hashes */
+    int binaryCachesParallelConnections;
+
+    /* Whether to enable HTTP2 */
+    bool enableHttp2;
+
+    /* How soon to expire tarballs like builtins.fetchTarball and (ugh, bad name) builtins.fetchurl */
+    int tarballTtl;
+
+    /* ??? */
+    string signedBinaryCaches;
+
+    /* ??? */
+    Strings substituters;
+
+    /* ??? */
+    Strings binaryCaches;
+
+    /* ??? */
+    Strings extraBinaryCaches;
+
+    /* Who we trust to ask the daemon to do unsafe things */
+    Strings trustedUsers;
+
+    /* ?Who we trust to use the daemon in safe ways */
+    Strings allowedUsers;
+
+    /* ??? */
+    bool printMissing;
+
     /* The hook to run just before a build to set derivation-specific
        build settings */
     Path preBuildHook;
@@ -196,11 +261,16 @@ struct Settings {
     Path netrcFile;
 
 private:
+    StringSet deprecatedOptions;
     SettingsMap settings, overrides;
 
+    void checkDeprecated(const string & name);
+
     void _get(string & res, const string & name);
+    void _get(string & res, const string & name1, const string & name2);
     void _get(bool & res, const string & name);
     void _get(StringSet & res, const string & name);
+    void _get(StringSet & res, const string & name1, const string & name2);
     void _get(Strings & res, const string & name);
     template<class N> void _get(N & res, const string & name);
 };