Implement --config-{guess,sub} options

1 files changed, 36 insertions, 0 deletions

diff --git a/build2/utility.txx b/build2/utility.txx
new file mode 100644
index 0000000..7848296
--- /dev/null
+++ b/build2/utility.txx
@@ -0,0 +1,36 @@
+// file      : build2/utility.txx -*- C++ -*-
+// copyright : Copyright (c) 2014-2016 Code Synthesis Ltd
+// license   : MIT; see accompanying LICENSE file
+
+namespace build2
+{
+  template <typename T>
+  T
+  run (const char* const* args, T (*f) (string&), bool err, sha256* checksum)
+  {
+    process pr (start_run (args, err));
+    ifdstream is (pr.in_ofd);
+
+    T r;
+
+    string l; // Last line of output.
+    while (is.peek () != ifdstream::traits_type::eof () && // Keep last line.
+           getline (is, l))
+    {
+      trim (l);
+
+      if (checksum != nullptr)
+        checksum->append (l);
+
+      if (r.empty ())
+        r = f (l);
+    }
+
+    is.close (); // Don't block.
+
+    if (!finish_run (args, err, pr, l))
+      r = T ();
+
+    return r;
+  }
+}