* Global configuration option `env-keep-derivations' to store pointer

  to derivations in user environments.  Nice for developers (since it
  prevents build-time-only dependencies from being GC'ed, in
  conjunction with `gc-keep-outputs').  Turned off by default.

3 files changed, 15 insertions, 3 deletions

diff --git a/src/libstore/gc.cc b/src/libstore/gc.cc
index 4d63d46ea1f5..98b863314ac9 100644
--- a/src/libstore/gc.cc
+++ b/src/libstore/gc.cc
@@ -306,7 +306,7 @@ void collectGarbage(GCAction action, PathSet & result)
 {
     result.clear();
 
-    string gcKeepOutputs = querySetting("gc-keep-outputs", "false");
+    bool gcKeepOutputs = queryBoolSetting("gc-keep-outputs", false);
 
     /* Acquire the global GC root.  This prevents
        a) New roots from being added.
@@ -330,7 +330,7 @@ void collectGarbage(GCAction action, PathSet & result)
     for (PathSet::const_iterator i = roots.begin(); i != roots.end(); ++i)
         computeFSClosure(canonPath(*i), livePaths);
 
-    if (gcKeepOutputs == "true") {
+    if (gcKeepOutputs) {
         /* Hmz, identical to storePathRequisites in nix-store. */
         for (PathSet::iterator i = livePaths.begin();
              i != livePaths.end(); ++i)
diff --git a/src/libstore/globals.cc b/src/libstore/globals.cc
index 22820f2fe8ac..4387c8acc2aa 100644
--- a/src/libstore/globals.cc
+++ b/src/libstore/globals.cc
@@ -52,7 +52,7 @@ static void readSettings()
         string name, sep, value;
         is >> name >> sep >> value;
         if (sep != "=" || !is)
-            throw Error(format("illegal configuration line `%1%'") % line);
+            throw Error(format("illegal configuration line `%1%' in `%2%'") % line % settingsFile);
         
         settings[name] = value;
     };
@@ -67,3 +67,13 @@ string querySetting(const string & name, const string & def)
     map<string, string>::iterator i = settings.find(name);
     return i == settings.end() ? def : i->second;
 }
+
+
+bool queryBoolSetting(const string & name, bool def)
+{
+    string value = querySetting(name, def ? "true" : "false");
+    if (value == "true") return true;
+    else if (value == "false") return false;
+    else throw Error(format("configuration option `%1%' should be either `true' or `false', not `%2%'")
+        % name % value);
+}
diff --git a/src/libstore/globals.hh b/src/libstore/globals.hh
index 0e851fd748c6..e2ae2ed655b3 100644
--- a/src/libstore/globals.hh
+++ b/src/libstore/globals.hh
@@ -55,5 +55,7 @@ extern bool readOnlyMode;
 
 string querySetting(const string & name, const string & def);
 
+bool queryBoolSetting(const string & name, bool def);
+
 
 #endif /* !__GLOBALS_H */