Add support for default options file

Now, if configured, the ODB compiler will load the default options
file (../etc/odb/default.options by default). This file can be used
for installation-wide customization, such as adding extra include
search paths.

2 files changed, 75 insertions, 1 deletions

diff --git a/configure.ac b/configure.ac
index a680089..7dc7e0b 100644
--- a/configure.ac
+++ b/configure.ac
@@ -31,7 +31,7 @@ AS_IF([test x$static_plugin = xyes],
 #
 AS_IF([test x$static_plugin = xno], GCC_PLUGIN)
 
-#
+# G++ name.
 #
 AC_ARG_WITH(
   [gxx-name],
@@ -53,6 +53,27 @@ AS_IF(
   [test "x$gxx_name" != x],
   [AC_DEFINE_UNQUOTED([GXX_NAME], ["$gxx_name"], [g++ binary.])])
 
+# Default options file.
+#
+AC_ARG_WITH(
+  [options-file],
+  [AC_HELP_STRING([--with-options-file=PATH], [default options file path to embed in the driver])],
+  [case $withval in
+     no)
+       options_file=
+       ;;
+     yes)
+       options_file=../etc/odb/default.options
+       ;;
+     *)
+       options_file="$withval"
+       ;;
+   esac],
+  [options_file=])
+
+AS_IF(
+  [test "x$options_file" != x],
+  [AC_DEFINE_UNQUOTED([DEFAULT_OPTIONS_FILE], ["$options_file"], [default options file path.])])
 
 # Create the libtool executable so that we can use it in further tests.
 #
diff --git a/odb/odb.cxx b/odb/odb.cxx
index 196329b..707173e 100644
--- a/odb/odb.cxx
+++ b/odb/odb.cxx
@@ -213,6 +213,54 @@ main (int argc, char* argv[])
     args.push_back ("g++");
 #endif // GXX_NAME
 
+    // Parse the default options file if we have one.
+    //
+    strings def_inc_dirs;
+#ifdef DEFAULT_OPTIONS_FILE
+    {
+      path file (DEFAULT_OPTIONS_FILE);
+
+      // If the path is relative, then use the driver's path as a base.
+      //
+      if (file.relative ())
+      {
+        path dp (driver_path (path (argv[0])));
+        file = dp.directory () / file;
+      }
+
+      int ac (3);
+      const char* av[4] = {argv[0], "--file", file.string ().c_str (), 0};
+      cli::argv_file_scanner s (ac, const_cast<char**> (av), "--file");
+
+      while (s.more ())
+      {
+        string a (s.next ());
+        size_t n (a.size ());
+
+        // -I
+        //
+        if (n > 1 && a[0] == '-' && a[1] == 'I')
+        {
+          def_inc_dirs.push_back (a);
+
+          if (n == 2) // -I /path
+          {
+            if (!s.more () || (a = s.next ()).empty ())
+            {
+              e << file << ": error: expected argument for the -I option"
+                << endl;
+              return 1;
+            }
+
+            def_inc_dirs.push_back (a);
+          }
+        }
+        else
+          plugin_args.push_back (a);
+      }
+    }
+#endif
+
     // Default options.
     //
     args.push_back ("-x");
@@ -326,6 +374,11 @@ main (int argc, char* argv[])
         plugin_args.push_back (a);
     }
 
+    // Add the default include directories (-I) after the user-supplied
+    // ones.
+    //
+    args.insert (args.end (), def_inc_dirs.begin (), def_inc_dirs.end ());
+
     // Obtain profile (-I) search paths.
     //
     paths prof_paths (profile_paths (args, argv[0]));