feat(utils): string utils + corresponding tests

tests/unit/utils/utils_tests.c

@@ -0,0 +1,97 @@
+#include <criterion/criterion.h>
+#include <criterion/new/assert.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/types.h>
+
+#include "utils/string_utils/string_utils.h"
+
+TestSuite(string_utils);
+
+Test(string_utils, skipblank_basic)
+{
+    char input[] = "  Hello World";
+    char expected_str[] = "Hello World";
+
+    ssize_t actual = skip_blanks(input);
+    ssize_t expected = 2;
+    cr_expect(eq(str, input, expected_str));
+    cr_expect(actual == expected);
+}
+
+Test(string_utils, skipblank_noblank)
+{
+    char input[] = "Hello World";
+    char expected_str[] = "Hello World";
+
+    ssize_t actual = skip_blanks(input);
+    ssize_t expected = 0;
+    cr_expect(eq(str, input, expected_str));
+    cr_expect(actual == expected);
+}
+
+Test(string_utils, skipblank_tab)
+{
+    char input[] = "\tHello World";
+    char expected_str[] = "Hello World";
+
+    ssize_t actual = skip_blanks(input);
+    ssize_t expected = 1;
+    cr_expect(eq(str, input, expected_str));
+    cr_expect(actual == expected);
+}
+
+Test(string_utils, skipblank_space_tab)
+{
+    char input[] = " \tHello World";
+    char expected_str[] = "Hello World";
+
+    ssize_t actual = skip_blanks(input);
+    ssize_t expected = 2;
+    cr_expect(eq(str, input, expected_str));
+    cr_expect(actual == expected);
+}
+
+Test(string_utils, skipblank_2tab_1space)
+{
+    char input[] = "\t \tHello World";
+    char expected_str[] = "Hello World";
+
+    ssize_t actual = skip_blanks(input);
+    ssize_t expected = 3;
+    cr_expect(eq(str, input, expected_str));
+    cr_expect(actual == expected);
+}
+
+Test(string_utils, skipblank_a_lot)
+{
+    char input[] = "\t   \t  \tHello World";
+    char expected_str[] = "Hello World";
+
+    ssize_t actual = skip_blanks(input);
+    ssize_t expected = 8;
+    cr_expect(eq(str, input, expected_str));
+    cr_expect(actual == expected);
+}
+
+Test(string_utils, skipblank_newline)
+{
+    char input[] = "\nHello World";
+    char expected_str[] = "\nHello World";
+
+    ssize_t actual = skip_blanks(input);
+    ssize_t expected = 0;
+    cr_expect(eq(str, input, expected_str));
+    cr_expect(actual == expected);
+}
+
+Test(string_utils, skipblank_nul)
+{
+    char *input = NULL;
+
+    ssize_t actual = skip_blanks(input);
+    ssize_t expected = 0;
+    cr_expect(input == NULL);
+    cr_expect(actual == expected);
+}