tests/unit/test_zustr2stp.c: Test ZUSTR2STP()

Signed-off-by: Alejandro Colomar <alx@kernel.org>

tests/unit/Makefile.am

@@ -11,7 +11,8 @@ check_PROGRAMS = \
     test_sprintf \
     test_strncpy \
     test_strtcpy \
-    test_xasprintf
+    test_xasprintf \
+    test_zustr2stp
 
 if ENABLE_LOGIND
 check_PROGRAMS += \
@@ -143,4 +144,16 @@ test_xasprintf_LDADD = \
     $(CMOCKA_LIBS) \
     $(NULL)
 
+test_zustr2stp_SOURCES = \
+    test_zustr2stp.c \
+    $(NULL)
+test_zustr2stp_CFLAGS = \
+    $(AM_CFLAGS) \
+    $(NULL)
+test_zustr2stp_LDFLAGS = \
+    $(NULL)
+test_zustr2stp_LDADD = \
+    $(CMOCKA_LIBS) \
+    $(NULL)
+
 endif # HAVE_CMOCKA

tests/unit/test_zustr2stp.c

@@ -0,0 +1,53 @@
+// SPDX-FileCopyrightText: 2024, Alejandro Colomar <alx@kernel.org>
+// SPDX-License-Identifier: BSD-3-Clause
+
+
+#include <config.h>
+
+#include <stddef.h>
+#include <string.h>
+
+#include <stdarg.h>  // Required by <cmocka.h>
+#include <stddef.h>  // Required by <cmocka.h>
+#include <setjmp.h>  // Required by <cmocka.h>
+#include <stdint.h>  // Required by <cmocka.h>
+#include <cmocka.h>
+
+#include "string/zustr2stp.h"
+
+
+static void test_ZUSTR2STP(void **state);
+
+
+int
+main(void)
+{
+    const struct CMUnitTest  tests[] = {
+        cmocka_unit_test(test_ZUSTR2STP),
+    };
+
+    return cmocka_run_group_tests(tests, NULL, NULL);
+}
+
+
+static void
+test_ZUSTR2STP(void **state)
+{
+	char  src[3] = {'1', '2', '3'};
+	char  dst[4];
+
+	assert_true(ZUSTR2STP(&dst, src) == dst + strlen("123"));
+	assert_true(strcmp("123", dst) == 0);
+
+	src[2] = '\0';
+	assert_true(ZUSTR2STP(&dst, src) == dst + strlen("12"));
+	assert_true(strcmp("12", dst) == 0);
+
+	src[1] = '\0';
+	assert_true(ZUSTR2STP(&dst, src) == dst + strlen("1"));
+	assert_true(strcmp("1", dst) == 0);
+
+	src[0] = '\0';
+	assert_true(ZUSTR2STP(&dst, src) == dst + strlen(""));
+	assert_true(strcmp("", dst) == 0);
+}