[advapi32] Fix returnvalue of RegOpenKeyA (with tests)

[Paul Vriens]

Hi,

I thought before going back to NtOpenKey, I'd start with RegOpenKeyA.

I assume more-or-less the same fixes will be needed for RegOpenKeyW and
RegOpenKeyEx*.

Changelog
  Fix returnvalue of RegOpenKeyA (with tests)

Cheers,

Paul
---
 dlls/advapi32/registry.c       |    3 +++
 dlls/advapi32/tests/registry.c |   11 +++++++++++
 2 files changed, 14 insertions(+), 0 deletions(-)

diff --git a/dlls/advapi32/registry.c b/dlls/advapi32/registry.c
index e99cce7..ad112aa 100644
--- a/dlls/advapi32/registry.c
+++ b/dlls/advapi32/registry.c
@@ -380,6 +380,9 @@ DWORD WINAPI RegOpenKeyW( HKEY hkey, LPC
  */
 DWORD WINAPI RegOpenKeyA( HKEY hkey, LPCSTR name, PHKEY retkey )
 {
+    if (!retkey)
+        return ERROR_INVALID_PARAMETER;
+
     if (!name || !*name)
     {
         *retkey = hkey;
diff --git a/dlls/advapi32/tests/registry.c b/dlls/advapi32/tests/registry.c
index 577838d..9a7f640 100644
--- a/dlls/advapi32/tests/registry.c
+++ b/dlls/advapi32/tests/registry.c
@@ -538,6 +538,17 @@ static void test_reg_open_key(void)
         ok(hkResult == NULL, "expected hkResult == NULL\n");
     }
 
+    /* Some NULL checks */
+
+    ret = RegOpenKeyA(NULL, NULL, NULL);
+    ok(ret == ERROR_INVALID_PARAMETER, "expected ERROR_INVALID_PARAMETER, got %ld\n", ret);
+
+    ret = RegOpenKeyA(HKEY_CURRENT_USER, NULL, NULL);
+    ok(ret == ERROR_INVALID_PARAMETER, "expected ERROR_INVALID_PARAMETER, got %ld\n", ret);
+
+    ret = RegOpenKeyA(NULL, "Software\\Wine\\Test", NULL);
+    ok(ret == ERROR_INVALID_PARAMETER, "expected ERROR_INVALID_PARAMETER, got %ld\n", ret);
+
     /* only send NULL hKey
      * the value of hkResult remains unchanged
      */
-- 
1.4.1