Add test mode for code coverage

Author: krkind

SConscript

@@ -1,5 +1,5 @@
 # Import environment
-Import('env')
+Import('env', 'mode')
 
 # Add include file absolute path
 env.Append(CPPPATH = [env.Dir('.').abspath])
@@ -10,6 +10,9 @@ env = env.Clone()
 # Add specific compiler flags
 env.AppendUnique(CCFLAGS = ['-std=c99'])
 
+if mode == 'test':
+  env.AppendUnique(CCFLAGS = ['--coverage'])
+
 # Point out all source files
 src = env.Split('''
   circularbuffer.c

test/SConscript

@@ -7,13 +7,16 @@ env = env.Clone()
 # Add compiler flags
 env.AppendUnique(CCFLAGS = ['-O0', '-g'])
 
+# Add test mode
+mode = 'test'
+
 # Build the test object
 lib = []
 
-lib += SConscript('../SConscript', variant_dir='libcbuf', duplicate=0, exports='env')
+lib += SConscript('../SConscript', variant_dir='libcbuf', duplicate=0, exports=['env', 'mode'])
 
 # Link needed libraries
-env.Prepend(LIBS = [lib, 'gtest', 'pthread'], LIBPATH = ['../../build_gtest/lib/'])
+env.Prepend(LIBS = [lib, 'gtest', 'gcov', 'pthread'], LIBPATH = ['../../build_gtest/lib/'])
 
 # Add include path for the Google test
 env.Append(CCFLAGS=('-isystem', '../googletest/googletest/include'))