Bugfix/bacnet real endian simplify (#89)

* Remove dependence on endian define

* Make use of existing big_endian function if BACNET_BIG_ENDIAN is not defined

* Add efficient endian macro option if available

Co-authored-by: Steve Karg <skarg@users.sourceforge.net>

test/bacnet/bacreal/Makefile

@@ -0,0 +1,43 @@
+#Makefile to build test case
+CC      = gcc
+SRC_DIR = ../../../src
+TEST_DIR = ../../../test
+INCLUDES = -I$(SRC_DIR) -I$(TEST_DIR)
+DEFINES = -DDEBUG_ENABLED=0
+
+CFLAGS  = -Wall $(INCLUDES) $(DEFINES) -g
+
+SRCS = main.c \
+	$(SRC_DIR)/bacnet/bacreal.c \
+	$(SRC_DIR)/bacnet/basic/sys/bigend.c \
+	$(TEST_DIR)/ctest.c
+
+TARGET_NAME = unittest
+ifeq ($(OS),Windows_NT)
+TARGET_EXT = .exe
+else
+TARGET_EXT =
+endif
+TARGET = $(TARGET_NAME)$(TARGET_EXT)
+
+all: ${TARGET}
+
+OBJS = ${SRCS:.c=.o}
+
+${TARGET}: ${OBJS}
+	${CC} -o $@ ${OBJS}
+
+.c.o:
+	${CC} -c ${CFLAGS} $*.c -o $@
+
+depend:
+	rm -f .depend
+	${CC} -MM ${CFLAGS} *.c >> .depend
+
+clean:
+	rm -rf ${TARGET} $(OBJS)
+
+test: ${TARGET}
+	./${TARGET}
+
+include: .depend

test/bacnet/bacreal/main.c

@@ -0,0 +1,98 @@
+/**
+ * @file
+ * @author Steve Karg
+ * @date April 2020
+ * @brief Test file for a REAL and DOUBLE encode and decode
+ *
+ * @section LICENSE
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+ * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+ * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+ * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+ * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+#include <stdio.h> 
+#include <stdint.h>
+#include <stdbool.h>
+#include <string.h>
+#include <ctype.h>
+#include <assert.h>
+#include <string.h>
+#include "bacnet/bacreal.h"
+#include "ctest.h"
+
+static void test_setup(void)
+{
+
+}
+
+static void test_cleanup(void)
+{
+
+}
+
+void testBACreal(Test *pTest)
+{
+    float real_value = 3.14159F, test_real_value = 0.0;
+    uint8_t apdu[50] = { 0 };
+    int len = 0, test_len = 0;
+
+    test_setup();
+    len = encode_bacnet_real(real_value, &apdu[0]);
+    ct_test(pTest, len == 4);
+    test_len = decode_real(&apdu[0], &test_real_value);
+    ct_test(pTest, test_len == len);
+    ct_test(pTest, test_real_value == real_value);
+    test_cleanup();
+}
+
+void testBACdouble(Test *pTest)
+{
+    double double_value = 3.1415927, test_double_value = 0.0;
+    uint8_t apdu[50] = { 0 };
+    int len = 0, test_len = 0;
+
+    test_setup();
+    len = encode_bacnet_double(double_value, &apdu[0]);
+    ct_test(pTest, len == 8);
+    test_len = decode_double(&apdu[0], &test_double_value);
+    ct_test(pTest, test_len == len);
+    ct_test(pTest, test_double_value == double_value);
+    test_cleanup();
+}
+
+int main(void)
+{
+    Test *pTest;
+    bool rc;
+
+    pTest = ct_create("BACreal", NULL);
+    /* individual tests */
+    rc = ct_addTestFunction(pTest, testBACreal);
+    assert(rc);
+    rc = ct_addTestFunction(pTest, testBACdouble);
+    assert(rc);
+
+    /* configure output */
+    ct_setStream(pTest, stdout);
+    ct_run(pTest);
+    (void)ct_report(pTest);
+    ct_destroy(pTest);
+
+    return 0;
+}
+