zip_open fails with error 18 when file path contains umlauts

[ZockerFloh7]

Dear authors of libzip,

first of all I want to thank you for your great zip library.
It was easy to implement and is much better in usage and performance than wxZip.

I write you because I have found a small issue.
When I try to open zip files using the zip_open function I get an error in some cases.
The function returns error code 18 when I try to open a zip with a file path containing umlauts.

#define ZIP_ER_INVAL 18 /* N Invalid argument */

Can you please tell me what I can do, to fix this issue?
I cannot prevent my users from opening zips where the file path contains umlauts.

Yours Sincerely

[dillof]

On wich operating system are you using libzip?

Can you trace through zip_open to see where the error occurs?

[ZockerFloh7]

Hey, thanks for your fast reply.
I am using Windows 7 Professional x64 with libzip 1.5.1.

This is the path that gets passed to the function:

C:\exchange\OfflineDatensätze\bP Rapid\NOK\EthSpy Fehler\D0001Z001\offlineDataset.zip;

The error happens in zip_source_win32utf8.c (line 62):
/* Convert fname from UTF-8 to Windows-friendly UTF-16. */ size = MultiByteToWideChar(CP_UTF8, MB_ERR_INVALID_CHARS, fname, -1, NULL, 0); if (size == 0) { zip_error_set(error, ZIP_ER_INVAL, 0); return NULL; }

Seems like the function MultiByteToWideChar returns zero, but I can´t imagine why.

[dillof]

Maybe the file name is not encoded in UTF-8, but some other encoding like ISO-8859-1. If so, you will have to convert it to UTF-8 before passing it to libzip.

[ZockerFloh7]

Okay, I have not much experience with encodings, here is the part of the code, where I try to open the archive:

c_archive = zip_open(c_fileName.c_str(), ZIP_RDONLY, &error);

c_fileName is just a std::string, I get it from a file choosing dialog.
Can this be the problem?
Can you tell me how to convert it to utf8?

[dillof]

Sorry, I'm not a Windows developer. Examine c_fileName to see wether it is in UTF-8.

[ZockerFloh7]

It seems like c_fileName is Latin(ISO-8859-1) encoded.
I converted it to UTF8 now, and its working with umlauts.
Thank you for your great support!