[PATCH 2/6] reg: Add path/key conversion functions

[Stefan Dösinger]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

Am 2014-10-27 13:10, schrieb Jonathan Vollebregt:
> +#define ARRAY_COUNT(A) (sizeof(A)/sizeof(*A))
Other places that use a macro like this call it ARRAY_SIZE.

> +typedef struct {
> +    HKEY key;
> +    const WCHAR *short_name;
> +    const WCHAR *long_name;
> +} hkey_rel;
Style :-)

> +static inline int path_rootname_cmp(const WCHAR *path, const WCHAR *name)
> +{
> +    DWORD length = strlenW(name);
> +
> +    return (strncmpiW(path, name, length) == 0 && (path[length] == 0 || path[length] == '\\'));
> +}
I don't like the names "path" and "name". I wondered why you're relying on the length of name. A better name for "path" could be "input", but I can't think of anything for "name".

> +static HKEY path_get_rootkey(const WCHAR *path)
> +{
> +    DWORD i;
> +    for (i = 0; i < ARRAY_COUNT(root_rels); i++)
> +    {
> +        if (path_rootname_cmp(path, root_rels[i].short_name) ||
> +            path_rootname_cmp(path, root_rels[i].long_name))
> +            return root_rels[i].key;
> +    }
> +
> +    reg_message(STRING_INVALID_KEY);
> +    return NULL;
> +}
Is it a good idea to write an error message from deep inside a helper function? What happens when you just pass the NULL root to RegOpenKey? Can you tell the cases for STRING_INVALID_KEY and STRING_CANNOT_FIND apart base on the return value?

You could also consider a function that returns an error string ID for each advapi32 Reg* error result. Then you can propagate the advapi32 return codes to main() and write the error string there. Depending on the possible failure modes this may or may not be possible.

> +    path = strchrW(path, '\\');
> +    if (!path)
> +        return k;
I see that this is why you need the trailing backslash elimination in the previous patch. But still, do you need this? What happens when you call e.g. RegOpenKey(HKEY_CURRENT_USER, "\\", &k)? If it returns HKEY_CURRENT_USER or a handle that points to HKEY_CURRENT_USER you're fine. Similarly for RegOpenKey(HKEY_CURRENT_USER, "", &k).

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2
Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/

iQIcBAEBAgAGBQJUTtS5AAoJEN0/YqbEcdMw+kEP/0DwI2fMgk2o6bKh1mCVwzeg
AFH+EKh1pAwpHBmIRHX7XzyDBAusd0GVH0+B5WQFnl+Fr49ybYqp8CGfytqm0H/e
lgqS0SCDZjaDTI5WO5zT/L5/VGhQ5tQHSQJiHS3UhXX3IBDXd7aYcbreSMHNcyJ8
ZPaFmVVCH8iRiR4qqMS8cJKXPxzx5tg5Ec9TpXfyYraI8YDPTNPOGlUipl9m5kwa
lrqjD+TbGbCOczq1mx6WSJnVxKWboWhz3FnzYDM0C8PzpJlRyzODWlfUHVMSLSmQ
xu9K/lXl2XJpmXbjFsCPZ5C4K3pRVH3poAtPNs+yOEeHkWTE2Pf3uyKNBwpW4ONU
3PFhn0beJM1scJY/LRjpCWLi74xA+FdBq6WDuxx2BpMoDvKCe/zV+LEY6zbymtxY
OsXQXXQwpcVBAC3mWQK0EWce8g2/he4PoPi8/l4ZakkCEAF4dqtdfSEQAccf9KfV
EeI8PJOAZRLoKAUQgKse2mYHG8V4EJEp8IQA0HcuWgR9zEMTpIUt08xdmU5cIWfu
Ena2T9phlAWmDIjcgr9haIHEreZkMI8DZI07XOmVAlZL44rSdkVop816I/ItTE98
CTwU6N0pD/V4htZcwWN7ZVojPK4AA7UD9NW7sg326drl2KIpk5j0ZmYq0/WwSL2o
uS2pHS9eKgBarX7GCXyd
=k2ys
-----END PGP SIGNATURE-----