Implement initial C++ configuration support

1 files changed, 134 insertions, 0 deletions

diff --git a/build/cxx/module.cxx b/build/cxx/module.cxx
new file mode 100644
index 0000000..eb7ca40
--- /dev/null
+++ b/build/cxx/module.cxx
@@ -0,0 +1,134 @@
+// file      : build/cxx/module.cxx -*- C++ -*-
+// copyright : Copyright (c) 2014-2015 Code Synthesis Tools CC
+// license   : MIT; see accompanying LICENSE file
+
+#include <build/cxx/module>
+
+#include <istream>
+#include <ext/stdio_filebuf.h>
+
+#include <build/path>
+#include <build/scope>
+#include <build/process>
+#include <build/diagnostics>
+
+using namespace std;
+
+namespace build
+{
+  namespace cxx
+  {
+    void
+    init (scope& root, scope& base, const location& l)
+    {
+      //@@ TODO: avoid multiple inits (generally, for modules).
+      //
+
+      tracer trace ("cxx::init");
+
+      //@@ Should it be this way?
+      //
+      if (&root != &base)
+        fail (l) << "cxx module must be initialized in project root scope";
+
+      //@@ TODO: need to register target types, rules here instead of main().
+
+      const path& out_root (root.path ());
+      level4 ([&]{trace << "for " << out_root << '/';});
+
+      // Configure.
+      //
+
+      // config.cxx
+      //
+      for (bool f (true); f; f = false)
+      {
+        auto val (root["config.cxx"]);
+
+        string v;
+
+        if (val)
+        {
+          if (&val.scope () != global_scope)
+            break; // A value from config.build.
+
+          v = val.as<const string&> ();
+        }
+        else
+          v = "g++"; // Default.
+
+        // Test it by trying to execute.
+        //
+        const char* args[] = {v.c_str (), "-dumpversion", nullptr};
+
+        if (verb >= 1)
+          print_process (args);
+        else
+          text << "test " << v;
+
+        string ver;
+        try
+        {
+          process pr (args, false, false, true);
+
+          __gnu_cxx::stdio_filebuf<char> fb (pr.in_ofd, ios_base::in);
+          istream is (&fb);
+
+          bool r (getline (is, ver));
+
+          if (!pr.wait ())
+            throw failed ();
+
+          if (!r)
+            fail << "unexpected output from " << v;
+        }
+        catch (const process_error& e)
+        {
+          error << "unable to execute " << v << ": " << e.what ();
+
+          if (e.child ())
+            exit (1);
+
+          throw failed ();
+        }
+
+        text << "toolchain version " << ver;
+
+        // Set on the project root.
+        //
+        root.variables["config.cxx"] = move (v);
+      }
+
+      // config.cxx.{p,c,l}options
+      // config.cxx.libs
+      //
+      // These are optional so all we need to do is "import" them
+      // into the root scope if they were specified on the command
+      // line.
+      //
+      if (auto val = root["config.cxx.poptions"])
+      {
+        if (&val.scope () == global_scope)
+          root.variables["config.cxx.poptions"] = val;
+      }
+
+      if (auto val = root["config.cxx.coptions"])
+      {
+        if (&val.scope () == global_scope)
+          root.variables["config.cxx.coptions"] = val;
+      }
+
+      if (auto val = root["config.cxx.loptions"])
+      {
+        if (&val.scope () == global_scope)
+          root.variables["config.cxx.loptions"] = val;
+      }
+
+      if (auto val = root["config.cxx.libs"])
+      {
+        if (&val.scope () == global_scope)
+          root.variables["config.cxx.libs"] = val;
+      }
+    }
+  }
+}