msi: Add initial implementation of MsiDatabaseMerge, with tests.

dlls/msi/msipriv.h

@@ -703,6 +703,8 @@ extern UINT MSI_RecordSetStream( MSIRECORD *, UINT, IStream * );
 extern UINT MSI_RecordDataSize( MSIRECORD *, UINT );
 extern UINT MSI_RecordStreamToFile( MSIRECORD *, UINT, LPCWSTR );
 extern UINT MSI_RecordCopyField( MSIRECORD *, UINT, MSIRECORD *, UINT );
+extern MSIRECORD *MSI_CloneRecord( MSIRECORD * );
+extern BOOL MSI_RecordsAreEqual( MSIRECORD *, MSIRECORD * );
 
 /* stream internals */
 extern UINT get_raw_stream( MSIHANDLE hdb, LPCWSTR stname, IStream **stm );

dlls/msi/record.c

@@ -903,3 +903,74 @@ UINT MSI_RecordStreamToFile( MSIRECORD *rec, UINT iField, LPCWSTR name )
 
     return r;
 }
+
+MSIRECORD *MSI_CloneRecord(MSIRECORD *rec)
+{
+    MSIRECORD *clone;
+    UINT r, i, count;
+
+    count = MSI_RecordGetFieldCount(rec);
+    clone = MSI_CreateRecord(count);
+    if (!clone)
+        return NULL;
+
+    for (i = 0; i <= count; i++)
+    {
+        if (rec->fields[i].type == MSIFIELD_STREAM)
+        {
+            if (FAILED(IStream_Clone(rec->fields[i].u.stream,
+                                     &clone->fields[i].u.stream)))
+            {
+                msiobj_release(&clone->hdr);
+                return NULL;
+            }
+        }
+        else
+        {
+            r = MSI_RecordCopyField(rec, i, clone, i);
+            if (r != ERROR_SUCCESS)
+            {
+                msiobj_release(&clone->hdr);
+                return NULL;
+            }
+        }
+    }
+
+    return clone;
+}
+
+BOOL MSI_RecordsAreEqual(MSIRECORD *a, MSIRECORD *b)
+{
+    UINT i;
+
+    if (a->count != b->count)
+        return FALSE;
+
+    for (i = 0; i <= a->count; i++)
+    {
+        if (a->fields[i].type != b->fields[i].type)
+            return FALSE;
+
+        switch (a->fields[i].type)
+        {
+            case MSIFIELD_NULL:
+                break;
+
+            case MSIFIELD_INT:
+                if (a->fields[i].u.iVal != b->fields[i].u.iVal)
+                    return FALSE;
+                break;
+
+            case MSIFIELD_WSTR:
+                if (lstrcmpW(a->fields[i].u.szwVal, b->fields[i].u.szwVal))
+                    return FALSE;
+                break;
+
+            case MSIFIELD_STREAM:
+            default:
+                return FALSE;
+        }
+    }
+
+    return TRUE;
+}