1 files changed, 19 insertions, 1 deletions
diff --git a/src/libutil/util.hh b/src/libutil/util.hh
index 7ebfd7cee0e9..9eebb67fdf3a 100644
--- a/src/libutil/util.hh
+++ b/src/libutil/util.hh
@@ -8,9 +8,15 @@
 #include <unistd.h>
 #include <signal.h>
 #include <functional>
-
+#include <limits>
 #include <cstdio>
 
+#ifndef HAVE_STRUCT_DIRENT_D_TYPE
+#define DT_UNKNOWN 0
+#define DT_REG 1
+#define DT_LNK 2
+#define DT_DIR 3
+#endif
 
 namespace nix {
 
@@ -353,6 +359,8 @@ bool statusOk(int status);
 /* Parse a string into an integer. */
 template<class N> bool string2Int(const string & s, N & n)
 {
+    if (string(s, 0, 1) == "-" && !std::numeric_limits<N>::is_signed)
+        return false;
     std::istringstream str(s);
     str >> n;
     return str && str.get() == EOF;
@@ -413,4 +421,14 @@ string base64Encode(const string & s);
 string base64Decode(const string & s);
 
 
+/* Get a value for the specified key from an associate container, or a
+   default value if the key doesn't exist. */
+template <class T>
+string get(const T & map, const string & key, const string & def = "")
+{
+    auto i = map.find(key);
+    return i == map.end() ? def : i->second;
+}
+
+
 }