CMocka example

README.md

Installation

$ make install

This will copy libcmoacka static library to lib/libcmocka.a and two .h files into include.

Compilation

$ make test

Running test

$ ./cmockatest
[==========] Running 4 test(s).
[ RUN      ] test_replace_char_null_ptr
[  ERROR   ] --- 0xffffffffffffffff == 0xffffffffffffffff
[   LINE   ] --- test.c:10: error: Failure!
[  FAILED  ] test_replace_char_null_ptr
[ RUN      ] test_replace_char_a_to_b
[       OK ] test_replace_char_a_to_b
[ RUN      ] test_replace_char_empty_str
[       OK ] test_replace_char_empty_str
[ RUN      ] test_replace_char_no_change
[       OK ] test_replace_char_no_change
[==========] 4 test(s) run.
[  PASSED  ] 3 test(s).
[  FAILED  ] 1 test(s), listed below:
[  FAILED  ] test_replace_char_null_ptr

 1 FAILED TEST(S)

Makefile

.PHONY: test install

CMOCKA_DIR=$(shell pwd)/cmocka-1.1.0
CMOCKA_BUILD_DIR=$(CMOCKA_DIR)/build
CMOCKA_OUT_DIR=$(CMOCKA_BUILD_DIR)/output

all: test

test:
	gcc test.c my_function.c -L./lib -I./ -I./include -lcmocka -o cmockatest

install:
	curl https://cmocka.org/files/1.1/cmocka-1.1.0.tar.xz -o cmocka.tar
	tar xf cmocka.tar
	rm cmocka.tar
	mkdir -p $(CMOCKA_OUT_DIR)
	cd $(CMOCKA_BUILD_DIR) && \
		 cmake -DWITH_STATIC_LIB=1 -DCMAKE_INSTALL_PREFIX=$(CMOCKA_OUT_DIR) .. && \
		 make && \
		 make install
	mkdir -p lib include
	cp $(CMOCKA_OUT_DIR)/lib/libcmocka.a lib
	cp $(CMOCKA_OUT_DIR)/include/*.h include
	rm -R $(CMOCKA_DIR)

my_function.c

#include <string.h>
#include "my_function.h"

int replace_char(char * const input, const char old, const char new){
  int len;
  int i, changed_count = 0;
  if(input == NULL){
    return REPLACE_CHAR_NULL_PTR;
  }
  len = strlen(input);
  for(i = 0; i < len; i++){
    if(input[i] == old){
      input[i] = new;
      changed_count++;
    }
  }
  return changed_count;
}

my_function.h

#define REPLACE_CHAR_NULL_PTR -1

int replace_char(char * const input, const char old, const char new);

test.c

#include <stdarg.h>
#include <stddef.h>
#include <setjmp.h>
#include <cmocka.h>
#include "my_function.h"

static void test_replace_char_null_ptr(void **state)
{
  int result = replace_char(NULL, 'a', 'b');
  assert_int_not_equal(result, REPLACE_CHAR_NULL_PTR); /* Will fail on purpose */
}

static void test_replace_char_a_to_b(void **state)
{
  char str[] = "aabc122";
  int result = replace_char(str, 'a', 'b');
  assert_int_equal(result, 2);
  assert_string_equal(str, "bbbc122");
}

static void test_replace_char_no_change(void **state)
{
  char str[] = "bbbbbbedsefge";
  int result = replace_char(str, 'a', 'b');
  assert_int_equal(result, 0);
  assert_string_equal(str, "bbbbbbedsefge");
}

static void test_replace_char_empty_str(void **state)
{
  char str[] = "";
  int result = replace_char(str, 'a', 'b');
  assert_int_equal(result, 0);
  assert_string_equal(str, "");
}

int main(void){
  const struct CMUnitTest tests[] = {
    cmocka_unit_test(test_replace_char_null_ptr),
    cmocka_unit_test(test_replace_char_a_to_b),
    cmocka_unit_test(test_replace_char_empty_str),
    cmocka_unit_test(test_replace_char_no_change)
  };
  return cmocka_run_group_tests(tests, NULL, NULL);
}