Add unit test framework and simple unit test example

test/unit/test_gpio.c

@@ -0,0 +1,46 @@
+#include <assert.h>
+#include <stdlib.h>
+#include <stdbool.h>
+#include <time.h>
+#include <sys/syscall.h>
+
+#include <fff.h>
+#include <utest.h>
+
+#include <ftdi_dev.h>
+#include <gpio.h>
+
+DEFINE_FFF_GLOBALS;
+
+FAKE_VOID_FUNC(ftdi_free, struct ftdi_context *);
+
+FAKE_VALUE_FUNC(int, ftdi_usb_open, struct ftdi_context *, int, int);
+FAKE_VALUE_FUNC(int, ftdi_usb_close, struct ftdi_context *);
+FAKE_VALUE_FUNC(struct ftdi_context *, ftdi_new);
+FAKE_VALUE_FUNC(const char *, ftdi_get_error_string, struct ftdi_context *);
+FAKE_VALUE_FUNC(int, ftdi_set_bitmode, struct ftdi_context *, unsigned char, unsigned char);
+FAKE_VALUE_FUNC(int, ftdi_read_data, struct ftdi_context *, unsigned char *, int);
+FAKE_VALUE_FUNC(int, ftdi_write_data, struct ftdi_context *, const unsigned char *, int);
+
+UTEST_MAIN();
+
+UTEST(gpio, gpio_open) {
+    struct gpio gpio_1;
+    struct ftdi_dev ftdi_obj;
+    struct ftdi_context ftdi_ctx;
+
+    ftdi_obj.ftdi = NULL,
+    ftdi_obj.is_open = false,
+    ftdi_obj.vendor_id = 0x0403,
+    ftdi_obj.product_id = 0x6001,
+    ftdi_obj.bit_mask = 0,
+    ftdi_obj.status_mask = 0,
+
+    gpio_1.pin = 0x08;
+    gpio_1.ftdi_dev = &ftdi_obj;
+
+    ASSERT_EQ(gpio_open(NULL), EXIT_FAILURE);
+
+    ftdi_new_fake.return_val = &ftdi_ctx;
+    ASSERT_EQ(gpio_open(&gpio_1), EXIT_SUCCESS);
+}