Add dynstr_init so unit tests can reset library.

This means that unit tests should not depend on the order in which
they run.

3 files changed, 35 insertions, 0 deletions

diff --git a/dynstr.c b/dynstr.c
index f445ea1..3c78e5e 100644
--- a/dynstr.c
+++ b/dynstr.c
@@ -18,6 +18,12 @@ struct Dynstr {
 static dynstr_error_handler *error_handler = dynstr_malloc_error_indicate;
 
 
+void dynstr_init(void)
+{
+    error_handler = dynstr_malloc_error_indicate;
+}
+
+
 dynstr_error_handler *dynstr_get_malloc_error_handler(void)
 {
     return error_handler;
diff --git a/dynstr.h b/dynstr.h
index a94d330..b668026 100644
--- a/dynstr.h
+++ b/dynstr.h
@@ -42,6 +42,11 @@
 typedef struct Dynstr Dynstr;
 
 
+/* Initialize or re-initialize the library. This sets all global variables
+ * used internally to their defaults. This is mainly useful for unit
+ * tests. */
+void dynstr_init(void);
+
 /* Type of callback functions for handling malloc failures. */
 typedef void dynstr_error_handler(int error, size_t size, void *oldptr);
 
diff --git a/unittests.c b/unittests.c
index 28a9e9d..e0880d1 100644
--- a/unittests.c
+++ b/unittests.c
@@ -25,6 +25,17 @@
     } while (0)
 
 
+static void setup(void)
+{
+    dynstr_init();
+}
+
+
+static void teardown(void)
+{
+}
+
+
 static int test_default_error_handler_is_indicate(void)
 {
     FAIL_UNLESS_EQUAL(dynstr_get_malloc_error_handler(),
@@ -42,6 +53,16 @@ static int test_sets_error_handler(void)
 }
 
 
+static int test_init_resets_error_handler(void)
+{
+    dynstr_set_malloc_error_handler(dynstr_malloc_error_abort);
+    dynstr_init();
+    FAIL_UNLESS_EQUAL(dynstr_get_malloc_error_handler(),
+                      dynstr_malloc_error_indicate);
+    return true;
+}
+
+
 static jmp_buf env;
 static void abort_handler(int signo)
 {
@@ -79,6 +100,7 @@ struct test {
 static const struct test tests[] = {
     TEST(test_default_error_handler_is_indicate),
     TEST(test_sets_error_handler),
+    TEST(test_init_resets_error_handler),
     TEST(test_abort_handler_calls_abort),
 };
 static const int num_tests = sizeof(tests) / sizeof(tests[0]);
@@ -89,9 +111,11 @@ int main(void)
 
     exit = EXIT_SUCCESS;
     for (int i = 0; i < num_tests; ++i) {
+        setup();
         if (!tests[i].test()) {
             exit = EXIT_FAILURE;
         }
+        teardown();
     }
     return exit;
 }