From 64d15602cca61c4915d5ec4a94ed1cbf0b0ac10d Mon Sep 17 00:00:00 2001
From: Josh Holtrop <jholtrop@gmail.com>
Date: Thu, 12 Sep 2013 23:35:34 -0400
Subject: [PATCH] add Library default builder

---
 build_tests/library/build.rb   |  4 ++++
 build_tests/library/one.c      |  8 ++++++++
 build_tests/library/three.c    |  0
 build_tests/library/two.c      |  0
 lib/rscons.rb                  |  2 ++
 lib/rscons/builders/library.rb | 33 +++++++++++++++++++++++++++++++++
 lib/rscons/environment.rb      |  3 +++
 spec/build_tests_spec.rb       | 13 +++++++++++++
 8 files changed, 63 insertions(+)
 create mode 100644 build_tests/library/build.rb
 create mode 100644 build_tests/library/one.c
 create mode 100644 build_tests/library/three.c
 create mode 100644 build_tests/library/two.c
 create mode 100644 lib/rscons/builders/library.rb

diff --git a/build_tests/library/build.rb b/build_tests/library/build.rb
new file mode 100644
index 0000000..3671c62
--- /dev/null
+++ b/build_tests/library/build.rb
@@ -0,0 +1,4 @@
+Rscons::Environment.new(echo: :command) do |env|
+  env.Program('library', ['lib.a', 'three.c'])
+  env.Library("lib.a", ['one.c', 'two.c'], 'CPPFLAGS' => ['-Dmake_lib'])
+end
diff --git a/build_tests/library/one.c b/build_tests/library/one.c
new file mode 100644
index 0000000..7b74439
--- /dev/null
+++ b/build_tests/library/one.c
@@ -0,0 +1,8 @@
+#include <stdio.h>
+
+#ifdef make_lib
+int main(int argc, char *argv[])
+{
+    printf("Library\n");
+}
+#endif
diff --git a/build_tests/library/three.c b/build_tests/library/three.c
new file mode 100644
index 0000000..e69de29
diff --git a/build_tests/library/two.c b/build_tests/library/two.c
new file mode 100644
index 0000000..e69de29
diff --git a/lib/rscons.rb b/lib/rscons.rb
index 744a71c..042cfa9 100644
--- a/lib/rscons.rb
+++ b/lib/rscons.rb
@@ -8,12 +8,14 @@ require "rscons/monkey/module"
 require "rscons/monkey/string"
 
 # default builders
+require "rscons/builders/library"
 require "rscons/builders/object"
 require "rscons/builders/program"
 
 # Namespace module for rscons classes
 module Rscons
   DEFAULT_BUILDERS = [
+    Library,
     Object,
     Program,
   ]
diff --git a/lib/rscons/builders/library.rb b/lib/rscons/builders/library.rb
new file mode 100644
index 0000000..cfaa76a
--- /dev/null
+++ b/lib/rscons/builders/library.rb
@@ -0,0 +1,33 @@
+require 'fileutils'
+
+module Rscons
+  # A default RScons builder that produces a static library archive.
+  class Library < Builder
+    def default_variables(env)
+      {
+        'AR' => 'ar',
+        'LIBSUFFIX' => '.a',
+        'ARFLAGS' => [],
+        'ARCOM' => ['$AR', 'rcs', '$ARFLAGS', '$TARGET', '$SOURCES']
+      }
+    end
+
+    def run(target, sources, cache, env, vars = {})
+      # build sources to linkable objects
+      objects = env.build_sources(sources, [env['OBJSUFFIX'], env['LIBSUFFIX']].flatten, cache, vars)
+      if objects
+        vars = vars.merge({
+          'TARGET' => target,
+          'SOURCES' => objects,
+        })
+        command = env.build_command(env['ARCOM'], vars)
+        unless cache.up_to_date?(target, command, objects)
+          FileUtils.rm_f(target)
+          return false unless env.execute("AR #{target}", command)
+          cache.register_build(target, command, objects)
+        end
+        target
+      end
+    end
+  end
+end
diff --git a/lib/rscons/environment.rb b/lib/rscons/environment.rb
index 782909b..376ce68 100644
--- a/lib/rscons/environment.rb
+++ b/lib/rscons/environment.rb
@@ -194,6 +194,9 @@ module Rscons
     def method_missing(method, *args)
       if @builders.has_key?(method.to_s)
         target, source, vars, *rest = args
+        unless vars.nil? or vars.is_a?(Hash) or vars.is_a?(VarSet)
+          raise "Unexpected construction variable set: #{vars.inspect}"
+        end
         source = [source] unless source.is_a?(Array)
         @targets[target] = {
           builder: @builders[method.to_s],
diff --git a/spec/build_tests_spec.rb b/spec/build_tests_spec.rb
index bf447f7..82c5179 100644
--- a/spec/build_tests_spec.rb
+++ b/spec/build_tests_spec.rb
@@ -153,4 +153,17 @@ describe Rscons do
     File.exists?('two_sources').should be_true
     `./two_sources`.should == "This is a C program with two sources.\n"
   end
+
+  it 'builds a static library archive' do
+    lines = test_dir('library')
+    lines.should == [
+      'gcc -c -o one.o -MMD -MF one.mf -Dmake_lib one.c',
+      'gcc -c -o two.o -MMD -MF two.mf -Dmake_lib two.c',
+      'ar rcs lib.a one.o two.o',
+      'gcc -c -o three.o -MMD -MF three.mf three.c',
+      'gcc -o library lib.a three.o',
+    ]
+    File.exists?('library').should be_true
+    `ar t lib.a`.should == "one.o\ntwo.o\n"
+  end
 end