1 files changed, 60 insertions, 5 deletions
diff --git a/ext/coverage/coverage.c b/ext/coverage/coverage.c
index b40b28bc21..3c6746f7aa 100644
--- a/ext/coverage/coverage.c
+++ b/ext/coverage/coverage.c
@@ -10,15 +10,67 @@
 
 #include "ruby.h"
 
-extern void rb_enable_coverages(void);
+static VALUE rb_mCoverage;
+
+extern VALUE rb_get_coverages(void);
+extern void rb_set_coverages(VALUE);
+extern void rb_reset_coverages(void);
+
+/*
+ * call-seq:
+ *    Coverage.start  => nil
+ *
+ * Enables coverage measurement.
+ */
+static VALUE
+rb_coverage_start(VALUE klass)
+{
+    if (!RTEST(rb_get_coverages())) {
+	VALUE coverages = rb_hash_new();
+	RBASIC(coverages)->klass = 0;
+	rb_set_coverages(coverages);
+    }
+}
+
+static int
+coverage_result_i(st_data_t key, st_data_t val, st_data_t dummy)
+{
+    VALUE coverage = (VALUE)val;
+    RBASIC(coverage)->klass = rb_cArray;
+    rb_ary_freeze(coverage);
+    return ST_CONTINUE;
+}
+
+/*
+ *  call-seq:
+ *     Coverage.result  => hash
+ *
+ * Returns a hash that contains filename as key and coverage array as value
+ * and disables coverage measurement.
+ */
+static VALUE
+rb_coverage_result(VALUE klass)
+{
+    VALUE coverages = rb_get_coverages();
+    if (!RTEST(coverages)) {
+	rb_raise(rb_eRuntimeError, "coverage measurement is not enabled");
+    }
+    RBASIC(coverages)->klass = rb_cHash;
+    st_foreach(RHASH_TBL(coverages), coverage_result_i, 0);
+    rb_hash_freeze(coverages);
+    rb_reset_coverages();
+    return coverages;
+}
 
 /* Coverage provides coverage measurement feature for Ruby.
+ * This feature is experimental, so these APIs may be changed in future.
  *
  * = Usage
  *
  * (1) require "coverage.so"
- * (2) require or load Ruby source file
- * (3) Coverage.result will return a hash that contains filename as key and
+ * (2) do Coverage.start
+ * (3) require or load Ruby source file
+ * (4) Coverage.result will return a hash that contains filename as key and
  *     coverage array as value.
  *
  * = Example
@@ -37,11 +89,14 @@ extern void rb_enable_coverages(void);
  *   [EOF]
  *
  *   require "coverage.so"
+ *   Coverage.start
  *   require "foo.rb"
- *   p COVERAGE__  #=> {"foo.rb"=>[1, 1, 10, nil, nil, 1, 1, nil, 0, nil]}
+ *   p Coverage.result  #=> {"foo.rb"=>[1, 1, 10, nil, nil, 1, 1, nil, 0, nil]}
  */
 void
 Init_coverage(void)
 {
-    rb_enable_coverages();
+    rb_mCoverage = rb_define_module("Coverage");
+    rb_define_module_function(rb_mCoverage, "start", rb_coverage_start, 0);
+    rb_define_module_function(rb_mCoverage, "result", rb_coverage_result, 0);
 }