tests: Use proper functions types instead of void (*fn)

We have several function parameters declared as void (*fn).  This is
just a stupid way to write void *, and the only purpose writing it
like that could serve is obscuring the sin of bypassing the type
system without need.

The original sin is commit 49ee359: its qtest_add_func() is a wrapper
for g_test_add_func().  Fix the parameter type to match
g_test_add_func()'s.  This uncovers type errors in ide-test.c; fix
them.

Commit 7949c0e faithfully repeated the sin for qtest_add_data_func().
Fix it the same way, along with a harmless type error uncovered in
vhost-user-test.c.

Commit 063c23d repeated it for qtest_add_abrt_handler().  The screwy
parameter gets assigned to GHook member func, so change its type to
match.  Requires wrapping kill_qemu() to keep the type checker happy.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
[AF/armbru: Inline GTestFunc/GTestDataFunc typedef for old GLib]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>

tests/ide-test.c

@@ -593,12 +593,12 @@ static void test_flush_nodev(void)
     ide_test_quit();
 }
 
-static void test_pci_retry_flush(const char *machine)
+static void test_pci_retry_flush(void)
 {
     test_retry_flush("pc");
 }
 
-static void test_isa_retry_flush(const char *machine)
+static void test_isa_retry_flush(void)
 {
     test_retry_flush("isapc");
 }

tests/libqtest.c

@@ -110,6 +110,11 @@ static void kill_qemu(QTestState *s)
     }
 }
 
+static void kill_qemu_hook_func(void *s)
+{
+    kill_qemu(s);
+}
+
 static void sigabrt_handler(int signo)
 {
     g_hook_list_invoke(&abrt_hooks, FALSE);
@@ -133,7 +138,7 @@ static void cleanup_sigabrt_handler(void)
     sigaction(SIGABRT, &sigact_old, NULL);
 }
 
-void qtest_add_abrt_handler(void (*fn), const void *data)
+void qtest_add_abrt_handler(GHookFunc fn, const void *data)
 {
     GHook *hook;
 
@@ -170,7 +175,7 @@ QTestState *qtest_init(const char *extra_args)
     sock = init_socket(socket_path);
     qmpsock = init_socket(qmp_socket_path);
 
-    qtest_add_abrt_handler(kill_qemu, s);
+    qtest_add_abrt_handler(kill_qemu_hook_func, s);
 
     s->qemu_pid = fork();
     if (s->qemu_pid == 0) {
@@ -755,14 +760,15 @@ void qtest_memread(QTestState *s, uint64_t addr, void *data, size_t size)
     g_strfreev(args);
 }
 
-void qtest_add_func(const char *str, void (*fn))
+void qtest_add_func(const char *str, void (*fn)(void))
 {
     gchar *path = g_strdup_printf("/%s/%s", qtest_get_arch(), str);
     g_test_add_func(path, fn);
     g_free(path);
 }
 
-void qtest_add_data_func(const char *str, const void *data, void (*fn))
+void qtest_add_data_func(const char *str, const void *data,
+                         void (*fn)(const void *))
 {
     gchar *path = g_strdup_printf("/%s/%s", qtest_get_arch(), str);
     g_test_add_data_func(path, data, fn);

tests/libqtest.h

@@ -416,7 +416,7 @@ const char *qtest_get_arch(void);
  * The path is prefixed with the architecture under test, as
  * returned by qtest_get_arch().
  */
-void qtest_add_func(const char *str, void (*fn));
+void qtest_add_func(const char *str, void (*fn)(void));
 
 /**
  * qtest_add_data_func:
@@ -428,7 +428,8 @@ void qtest_add_func(const char *str, void (*fn));
  * The path is prefixed with the architecture under test, as
  * returned by qtest_get_arch().
  */
-void qtest_add_data_func(const char *str, const void *data, void (*fn));
+void qtest_add_data_func(const char *str, const void *data,
+                         void (*fn)(const void *));
 
 /**
  * qtest_add:
@@ -450,7 +451,7 @@ void qtest_add_data_func(const char *str, const void *data, void (*fn));
         g_free(path); \
     } while (0)
 
-void qtest_add_abrt_handler(void (*fn), const void *data);
+void qtest_add_abrt_handler(GHookFunc fn, const void *data);
 
 /**
  * qtest_start:

tests/vhost-user-test.c

@@ -173,8 +173,9 @@ static void wait_for_fds(TestServer *s)
     g_mutex_unlock(&s->data_mutex);
 }
 
-static void read_guest_mem(TestServer *s)
+static void read_guest_mem(const void *data)
 {
+    TestServer *s = (void *)data;
     uint32_t *guest_mem;
     int i, j;
     size_t size;