1 files changed, 52 insertions, 18 deletions

diff --git a/src/libstore/store-api.hh b/src/libstore/store-api.hh
index d03e70849f93..067309c9e956 100644
--- a/src/libstore/store-api.hh
+++ b/src/libstore/store-api.hh
@@ -6,6 +6,7 @@
 #include "lru-cache.hh"
 #include "sync.hh"
 #include "globals.hh"
+#include "config.hh"
 
 #include <atomic>
 #include <limits>
@@ -81,12 +82,7 @@ struct GCResults
 
     /* For `gcReturnDead', `gcDeleteDead' and `gcDeleteSpecific', the
        number of bytes that would be or was freed. */
-    unsigned long long bytesFreed;
-
-    GCResults()
-    {
-        bytesFreed = 0;
-    }
+    unsigned long long bytesFreed = 0;
 };
 
 
@@ -128,7 +124,7 @@ struct ValidPathInfo
        of an output path of a derivation were actually produced by
        that derivation. In the intensional model, we have to trust
        that a particular output path was produced by a derivation; the
-       path name then implies the contents.)
+       path then implies the contents.)
 
        Ideally, the content-addressability assertion would just be a
        Boolean, and the store path would be computed from
@@ -229,19 +225,23 @@ struct BuildResult
 };
 
 
-class Store : public std::enable_shared_from_this<Store>
+class Store : public std::enable_shared_from_this<Store>, public Config
 {
 public:
 
     typedef std::map<std::string, std::string> Params;
 
-    const Path storeDir;
+    const PathSetting storeDir_{this, false, settings.nixStore,
+        "store", "path to the Nix store"};
+    const Path storeDir = storeDir_;
+
+    const Setting<int> pathInfoCacheSize{this, 65536, "path-info-cache-size", "size of the in-memory store path information cache"};
 
 protected:
 
     struct State
     {
-        LRUCache<std::string, std::shared_ptr<ValidPathInfo>> pathInfoCache{64 * 1024};
+        LRUCache<std::string, std::shared_ptr<ValidPathInfo>> pathInfoCache;
     };
 
     Sync<State> state;
@@ -324,8 +324,10 @@ protected:
 
 public:
 
-    /* Query which of the given paths is valid. */
-    virtual PathSet queryValidPaths(const PathSet & paths);
+    /* Query which of the given paths is valid. Optionally, try to
+       substitute missing paths. */
+    virtual PathSet queryValidPaths(const PathSet & paths,
+        bool maybeSubstitute = false);
 
     /* Query the set of all valid paths. Note that for some store
        backends, the name part of store paths may be omitted
@@ -511,7 +513,7 @@ public:
        `storePath' is returned; that is, the closures under the
        `referrers' relation instead of the `references' relation is
        returned. */
-    void computeFSClosure(const PathSet & paths,
+    virtual void computeFSClosure(const PathSet & paths,
         PathSet & out, bool flipDirection = false,
         bool includeOutputs = false, bool includeDerivers = false);
 
@@ -522,7 +524,7 @@ public:
     /* Given a set of paths that are to be built, return the set of
        derivations that will be built, and the set of output paths
        that will be substituted. */
-    void queryMissing(const PathSet & targets,
+    virtual void queryMissing(const PathSet & targets,
         PathSet & willBuild, PathSet & willSubstitute, PathSet & unknown,
         unsigned long long & downloadSize, unsigned long long & narSize);
 
@@ -566,6 +568,18 @@ public:
        if they lack a signature. */
     virtual bool isTrusted() { return false; }
 
+    /* Return the build log of the specified store path, if available,
+       or null otherwise. */
+    virtual std::shared_ptr<std::string> getBuildLog(const Path & path)
+    { return nullptr; }
+
+    /* Hack to allow long-running processes like hydra-queue-runner to
+       occasionally flush their path info cache. */
+    void clearPathInfoCache()
+    {
+        state.lock()->pathInfoCache.clear();
+    }
+
 protected:
 
     Stats stats;
@@ -576,9 +590,20 @@ protected:
 class LocalFSStore : public virtual Store
 {
 public:
-    const Path rootDir;
-    const Path stateDir;
-    const Path logDir;
+
+    // FIXME: the (Store*) cast works around a bug in gcc that causes
+    // it to emit the call to the Option constructor. Clang works fine
+    // either way.
+    const PathSetting rootDir{(Store*) this, true, "",
+        "root", "directory prefixed to all other paths"};
+    const PathSetting stateDir{(Store*) this, false,
+        rootDir != "" ? rootDir + "/nix/var/nix" : settings.nixStateDir,
+        "state", "directory where Nix will store state"};
+    const PathSetting logDir{(Store*) this, false,
+        rootDir != "" ? rootDir + "/nix/var/log/nix" : settings.nixLogDir,
+        "log", "directory where Nix will store state"};
+
+    const static string drvsLogDir;
 
     LocalFSStore(const Params & params);
 
@@ -595,6 +620,8 @@ public:
     {
         return getRealStoreDir() + "/" + baseNameOf(storePath);
     }
+
+    std::shared_ptr<std::string> getBuildLog(const Path & path) override;
 };
 
 
@@ -642,8 +669,10 @@ void removeTempRoots();
    set to true *unless* you're going to collect garbage. */
 ref<Store> openStore(const std::string & uri = getEnv("NIX_REMOTE"));
 
+ref<Store> openStore(const std::string & uri, const Store::Params & params);
 
-void copyPaths(ref<Store> from, ref<Store> to, const Paths & storePaths, bool substitute = false);
+
+void copyPaths(ref<Store> from, ref<Store> to, const PathSet & storePaths, bool substitute = false);
 
 enum StoreType {
     tDaemon,
@@ -687,6 +716,11 @@ ValidPathInfo decodeValidPathInfo(std::istream & str,
     bool hashGiven = false);
 
 
+/* Compute the content-addressability assertion (ValidPathInfo::ca)
+   for paths created by makeFixedOutputPath() / addToStore(). */
+std::string makeFixedOutputCA(bool recursive, const Hash & hash);
+
+
 MakeError(SubstError, Error)
 MakeError(BuildError, Error) /* denotes a permanent build failure */
 MakeError(InvalidPath, Error)