Move /src to /subprojects

This will facilitate breaking up Nix into multiple packages for each
component with Meson.

subprojects/libstore/pathlocks.cc

@@ -0,0 +1,41 @@
+#include "pathlocks.hh"
+#include "util.hh"
+#include "sync.hh"
+#include "signals.hh"
+
+#include <cerrno>
+#include <cstdlib>
+
+
+namespace nix {
+
+PathLocks::PathLocks()
+    : deletePaths(false)
+{
+}
+
+
+PathLocks::PathLocks(const PathSet & paths, const std::string & waitMsg)
+    : deletePaths(false)
+{
+    lockPaths(paths, waitMsg);
+}
+
+
+PathLocks::~PathLocks()
+{
+    try {
+        unlock();
+    } catch (...) {
+        ignoreExceptionInDestructor();
+    }
+}
+
+
+void PathLocks::setDeletion(bool deletePaths)
+{
+    this->deletePaths = deletePaths;
+}
+
+
+}