Initial support for command line variables

7 files changed, 167 insertions, 89 deletions

diff --git a/build/b.cxx b/build/b.cxx
index c676f8a..bd02052 100644
--- a/build/b.cxx
+++ b/build/b.cxx
@@ -12,7 +12,6 @@
 
 #include <sstream>
 #include <cassert>
-#include <iostream> //@@ TMP, for dump()
 #include <typeinfo>
 #include <system_error>
 
@@ -32,6 +31,9 @@
 #include <build/context>
 #include <build/utility>
 #include <build/filesystem>
+
+#include <build/token>
+#include <build/lexer>
 #include <build/parser>
 
 using namespace std;
@@ -223,6 +225,40 @@ main (int argc, char* argv[])
     //
     reset ();
 
+    // Parse command line variables. They should come before the
+    // buildspec.
+    //
+    int argi (1);
+    for (; argi != argc; argi++)
+    {
+      const char* s (argv[argi]);
+
+      istringstream is (s);
+      is.exceptions (istringstream::failbit | istringstream::badbit);
+      lexer l (is, "<cmdline>");
+      token t (l.next ());
+
+      if (t.type () == token_type::eos)
+        continue; // Whitespace-only argument.
+
+      // Unless this is a name followed by = or +=, assume it is
+      // a start of the buildspec.
+      //
+      if (t.type () != token_type::name)
+        break;
+
+      token_type tt (l.next ().type ());
+
+      if (tt != token_type::equal && tt != token_type::plus_equal)
+        break;
+
+      parser p;
+      t = p.parse_variable (l, *root_scope, t.name (), tt);
+
+      if (t.type () != token_type::eos)
+        fail << "unexpected " << t << " in variable " << s;
+    }
+
     // Parse the buildspec.
     //
     buildspec bspec;
@@ -235,10 +271,10 @@ main (int argc, char* argv[])
       // which argument is invalid).
       //
       string s;
-      for (int i (1); i != argc;)
+      for (; argi != argc;)
       {
-        s += argv[i];
-        if (++i != argc)
+        s += argv[argi];
+        if (++argi != argc)
           s += ' ';
       }
 
diff --git a/build/buildfile b/build/buildfile
index 93f9179..95899fd 100644
--- a/build/buildfile
+++ b/build/buildfile
@@ -1,6 +1,7 @@
 cxx = cxx/{target rule}
 config = config/{operation module}
 
-exe{b1}: cxx{b algorithm parser lexer name operation spec scope variable \
-  target prerequisite rule file module native context search diagnostics \
-  process timestamp path utility filesystem dump $config $cxx}
+exe{b1}: cxx{b algorithm name operation spec scope variable target \
+  prerequisite rule file module native context search diagnostics \
+  token lexer parser process timestamp path utility filesystem dump \
+  $config $cxx}
diff --git a/build/lexer b/build/lexer
index 5f91dc4..81225e0 100644
--- a/build/lexer
+++ b/build/lexer
@@ -30,6 +30,9 @@ namespace build
   public:
     lexer (std::istream& is, const std::string& name): is_ (is), fail (name) {}
 
+    const std::string&
+    name () const {return fail.name_;}
+
     // Note: sets mode for the next token. If mode is pairs, then
     // the second argument specifies the separator character.
     //
diff --git a/build/parser b/build/parser
index 94a5bdf..4423e25 100644
--- a/build/parser
+++ b/build/parser
@@ -33,6 +33,9 @@ namespace build
     buildspec
     parse_buildspec (std::istream&, const std::string& name);
 
+    token
+    parse_variable (lexer&, scope&, std::string name, token_type kind);
+
     // Recursive descent parser.
     //
   private:
@@ -53,6 +56,9 @@ namespace build
     void
     using_ (token&, token_type&);
 
+    void
+    variable (token&, token_type&, std::string name, token_type kind);
+
     names_type
     names (token& t, token_type& tt)
     {
diff --git a/build/parser.cxx b/build/parser.cxx
index 617f22b..e2b11f0 100644
--- a/build/parser.cxx
+++ b/build/parser.cxx
@@ -27,11 +27,6 @@ using namespace std;
 
 namespace build
 {
-  // Output the token type and value in a format suitable for diagnostics.
-  //
-  ostream&
-  operator<< (ostream&, const token&);
-
   static location
   get_location (const token&, const void*);
 
@@ -70,6 +65,21 @@ namespace build
     process_default_target (t);
   }
 
+  token parser::
+  parse_variable (lexer& l, scope& s, string name, token_type kind)
+  {
+    path_ = &l.name ();
+    lexer_ = &l;
+    scope_ = &s;
+
+    token t (type::eos, false, 0, 0);
+    type tt;
+    next (t, tt);
+
+    variable (t, tt, name, kind);
+    return t;
+  }
+
   void parser::
   clause (token& t, token_type& tt)
   {
@@ -305,21 +315,11 @@ namespace build
       //
       if (tt == type::equal || tt == type::plus_equal)
       {
-        bool assign (tt == type::equal);
-
         // LHS should be a single, simple name.
         //
         if (ns.size () != 1 || !ns[0].type.empty () || !ns[0].dir.empty ())
           fail (t) << "variable name expected before " << t;
 
-        next (t, tt);
-
-        names_type vns (tt != type::newline && tt != type::eos
-                        ? names (t, tt)
-                        : names_type ());
-
-        // Enter the variable.
-        //
         string name;
         if (ns[0].value.front () == '.') // Fully qualified name.
           name.assign (ns[0].value, 1, string::npos);
@@ -327,48 +327,9 @@ namespace build
           //@@ TODO: append namespace if any.
           name = move (ns[0].value);
 
-        const variable& var (variable_pool.find (move (name)));
-
-        if (assign)
-        {
-          value_ptr& val (scope_->variables[var]);
-
-          if (val == nullptr) // Initialization.
-          {
-            val.reset (new list_value (*scope_, move (vns)));
-          }
-          else // Assignment.
-          {
-            //@@ TODO: assuming it is a list.
-            //
-            dynamic_cast<list_value&> (*val).data = move (vns);
-          }
-        }
-        else
-        {
-          if (auto val = (*scope_)[var])
-          {
-            //@@ TODO: assuming it is a list.
-            //
-            list_value* lv (&val.as<list_value&> ());
-
-            if (&lv->scope != scope_) // Append to value from parent scope?
-            {
-              list_value_ptr nval (new list_value (*scope_, lv->data));
-              lv = nval.get (); // Append to.
-              scope_->variables.emplace (var, move (nval));
-            }
-
-            lv->data.insert (lv->data.end (),
-                             make_move_iterator (vns.begin ()),
-                             make_move_iterator (vns.end ()));
-          }
-          else // Initialization.
-          {
-            list_value_ptr nval (new list_value (*scope_, move (vns)));
-            scope_->variables.emplace (var, move (nval));
-          }
-        }
+        type kind (tt);
+        next (t, tt);
+        variable (t, tt, move (name), kind);
 
         if (tt == type::newline)
           next (t, tt);
@@ -648,6 +609,61 @@ namespace build
   }
 
   void parser::
+  variable (token& t, token_type& tt, string name, token_type kind)
+  {
+    bool assign (kind == type::equal);
+
+    names_type vns (tt != type::newline && tt != type::eos
+                    ? names (t, tt)
+                    : names_type ());
+
+    // Enter the variable.
+    //
+    const auto& var (variable_pool.find (move (name)));
+
+    if (assign)
+    {
+      value_ptr& val (scope_->variables[var]);
+
+      if (val == nullptr) // Initialization.
+      {
+        val.reset (new list_value (*scope_, move (vns)));
+      }
+      else // Assignment.
+      {
+        //@@ TODO: assuming it is a list.
+        //
+        dynamic_cast<list_value&> (*val).data = move (vns);
+      }
+    }
+    else
+    {
+      if (auto val = (*scope_)[var])
+      {
+        //@@ TODO: assuming it is a list.
+        //
+        list_value* lv (&val.as<list_value&> ());
+
+        if (&lv->scope != scope_) // Append to value from parent scope?
+        {
+          list_value_ptr nval (new list_value (*scope_, lv->data));
+          lv = nval.get (); // Append to.
+          scope_->variables.emplace (var, move (nval));
+        }
+
+        lv->data.insert (lv->data.end (),
+                         make_move_iterator (vns.begin ()),
+                         make_move_iterator (vns.end ()));
+      }
+      else // Initialization.
+      {
+        list_value_ptr nval (new list_value (*scope_, move (vns)));
+        scope_->variables.emplace (var, move (nval));
+      }
+    }
+  }
+
+  void parser::
   names (token& t,
          type& tt,
          names_type& ns,
@@ -830,7 +846,7 @@ namespace build
           //@@ TODO: append namespace if any.
           n = t.name ();
 
-        const variable& var (variable_pool.find (move (n)));
+        const auto& var (variable_pool.find (move (n)));
         auto val ((*scope_)[var]);
 
         // Undefined namespaces variables are not allowed.
@@ -1289,28 +1305,4 @@ namespace build
     const string& p (**static_cast<const string* const*> (data));
     return location (p.c_str (), t.line (), t.column ());
   }
-
-  // Output the token type and value in a format suitable for diagnostics.
-  //
-  ostream&
-  operator<< (ostream& os, const token& t)
-  {
-    switch (t.type ())
-    {
-    case token_type::eos:            os << "<end-of-file>"; break;
-    case token_type::newline:        os << "<newline>"; break;
-    case token_type::pair_separator: os << "<pair separator>"; break;
-    case token_type::colon:          os << ":"; break;
-    case token_type::lcbrace:        os << "{"; break;
-    case token_type::rcbrace:        os << "}"; break;
-    case token_type::equal:          os << "="; break;
-    case token_type::plus_equal:     os << "+="; break;
-    case token_type::dollar:         os << "$"; break;
-    case token_type::lparen:         os << "("; break;
-    case token_type::rparen:         os << ")"; break;
-    case token_type::name:           os << t.name (); break;
-    }
-
-    return os;
-  }
 }
diff --git a/build/token b/build/token
index f7e45dc..7b0223b 100644
--- a/build/token
+++ b/build/token
@@ -6,6 +6,7 @@
 #define BUILD_TOKEN
 
 #include <string>
+#include <iosfwd>
 #include <cstddef> // size_t
 #include <cstdint> // uint64_t
 #include <cassert>
@@ -61,6 +62,11 @@ namespace build
     std::uint64_t l_;
     std::uint64_t c_;
   };
+
+  // Output the token value in a format suitable for diagnostics.
+  //
+  std::ostream&
+  operator<< (std::ostream&, const token&);
 }
 
 #endif // BUILD_TOKEN
diff --git a/build/token.cxx b/build/token.cxx
new file mode 100644
index 0000000..33d30a8
--- /dev/null
+++ b/build/token.cxx
@@ -0,0 +1,34 @@
+// file      : build/token.cxx -*- C++ -*-
+// copyright : Copyright (c) 2014-2015 Code Synthesis Tools CC
+// license   : MIT; see accompanying LICENSE file
+
+#include <build/token>
+
+#include <ostream>
+
+using namespace std;
+
+namespace build
+{
+  ostream&
+  operator<< (ostream& os, const token& t)
+  {
+    switch (t.type ())
+    {
+    case token_type::eos:            os << "<end-of-file>"; break;
+    case token_type::newline:        os << "<newline>"; break;
+    case token_type::pair_separator: os << "<pair separator>"; break;
+    case token_type::colon:          os << ":"; break;
+    case token_type::lcbrace:        os << "{"; break;
+    case token_type::rcbrace:        os << "}"; break;
+    case token_type::equal:          os << "="; break;
+    case token_type::plus_equal:     os << "+="; break;
+    case token_type::dollar:         os << "$"; break;
+    case token_type::lparen:         os << "("; break;
+    case token_type::rparen:         os << ")"; break;
+    case token_type::name:           os << t.name (); break;
+    }
+
+    return os;
+  }
+}