3 files changed, 18 insertions, 9 deletions
diff --git a/src/libstore/globals.cc b/src/libstore/globals.cc
index a69bc0c30..fc338892f 100644
--- a/src/libstore/globals.cc
+++ b/src/libstore/globals.cc
@@ -75,17 +75,22 @@ Strings querySetting(const string & name, const Strings & def)
 }
 
 
-bool queryBoolSetting(const string & name, bool def)
+string querySetting(const string & name, const string & def)
 {
     Strings defs;
-    if (def) defs.push_back("true"); else defs.push_back("false");
-    
+    defs.push_back(def);
+
     Strings value = querySetting(name, defs);
     if (value.size() != 1)
-        throw Error(format("configuration option `%1%' should be either `true' or `false', not a list")
-            % name);
-    
-    string v = value.front();
+        throw Error(format("configuration option `%1%' should not be a list") % name);
+
+    return value.front();
+}
+
+
+bool queryBoolSetting(const string & name, bool def)
+{
+    string v = querySetting(name, def ? "true" : "false");
     if (v == "true") return true;
     else if (v == "false") return false;
     else throw Error(format("configuration option `%1%' should be either `true' or `false', not `%2%'")
diff --git a/src/libstore/globals.hh b/src/libstore/globals.hh
index cb199fd36..b5de709f7 100644
--- a/src/libstore/globals.hh
+++ b/src/libstore/globals.hh
@@ -56,6 +56,8 @@ extern bool readOnlyMode;
 
 Strings querySetting(const string & name, const Strings & def);
 
+string querySetting(const string & name, const string & def);
+
 bool queryBoolSetting(const string & name, bool def);
 
 
diff --git a/src/libstore/store.cc b/src/libstore/store.cc
index 25e2d6e36..94c992f22 100644
--- a/src/libstore/store.cc
+++ b/src/libstore/store.cc
@@ -82,12 +82,14 @@ void openDB(bool reserveSpace)
 
     try {
         Path reservedPath = nixDBPath + "/reserved";
-        off_t reservedSize = 1024 * 1024;
+        string s = querySetting("gc-reserved-space", "");
+        int reservedSize;
+        if (!string2Int(s, reservedSize)) reservedSize = 1024 * 1024;
         if (reserveSpace) {
             struct stat st;
             if (stat(reservedPath.c_str(), &st) == -1 ||
                 st.st_size != reservedSize)
-                writeFile(reservedPath, string(1024 * 1024, 'X'));
+                writeFile(reservedPath, string(reservedSize, 'X'));
         }
         else
             deletePath(reservedPath);