Compiled binary under Ubuntu Linux 22.04 works flawlessly; not so well under macOS 11.7.9 [includes possible solution]

[GwynethLlewelyn]

Hi,

(Disclaimer: I'm actually Portuguese, but for the sake of non-Portuguese speakers, I'll post this in English instead).

For years and years, I have been trying to get good old rclone to connect to MEO Cloud using the Dropbox API, which should work; my problem was only to make sure I get a valid reply from MEO's servers! And this, in turn, pushed me to take a look at how others have dealt with the issue.

Firstly, I installed your application on a Linux x64 server running Ubuntu 22.04. Compiling with gcc 11.4.0 provided a clean, working executable. meocloud-upload --init recognised my authentication details without a glitch (after I switched the authentication type to OOB), I inserted the PIN, and it accepted it, saving the configuration as expected. Then I uploaded a file; no surprises there, it worked fine.

Secondly, I tried to do the same under macOS 11.7.9 (also x64). The default compiler I've got installed (via homebrew) is clang 17.0.6, mostly because Apple's version is stuck with 13.0.0 (way too old). Apple's gcc is actually symlinked by Apple to clang; I have gcc 13.2.0 but it's a pain to get it set up... therefore, I just used clang.

clang, under macOS, compiles fine (interestingly, the warnings are slightly different, but the compilation succeeds). The executable works, and, like the Linux version, it accepts my authentication details, calls MEO's auth server, displays the URL for getting the authentication, which, in turn, will correctly generate the appropriate PIN... copy-paste it into the CLI, get the refresh token and so forth... and then it gives an error. And stops the configuration.

Oh, and no ~/.meocloud.conf is ever written (or overwritten).

I experimented many different things, including creating a fresh, new ~/.meocloud.conf manually, see if it helped, and forcing meocloud-update to read from it. It clearly ignored the file, therefore requesting an initialisation. Once again, though, the process completed successfully, returning what I presume to be a valid token, but then it mysteriously fails with the [Erro] message.

By looking at the code, it seems that the reason for the failure to write ~/.meocloud.conf is easily explained:

In file Meocloud_API.cpp, under API::WriteFile(), line 403 shows:

#ifdef OS_UNIX
//... do some magic with file descriptors

Okay, that tag is not familiar to me, and what might be happening is that Homebrew's clang doesn't define it explicitly.

And, indeed, this is a locally-defined tag, along with a few others, which are explicitly set under Utils.h, around lines 6-9:

Utils.h (lines 6-9)

#ifdef __unix__


#define OS_UNIX

While it seems that GCC does, indeed, define __unix__ under Linux, there is no guarantee whatsoever that it's being defined under other Unix or Unix-like systems. In fact, the recommended line to check for most Unix/Unix-like flavours is rather long, e.g.

#if !defined(_WIN32) && (defined(__unix__) || defined(__unix) || (defined(__APPLE__) && defined(__MACH__)))

This should handle pretty much everything out there (allegedly, even Darwin, upon which macOS is based, will also define __APPLE__ & __MACH__).

Once I've made this simple change, everything compiled flawlessly and produced identical results to the Linux version 😄

But that line is rather long, and perhaps it's worth considering the alternative — i.e., define OS_UNIX as being not Windows, since the number of 'official' tags for Windows are very few (_WIN32 being the most common one).

Of course, there might be exceptions out there — for instance, what does iOS or Android return? Both, of course, are Unix-flavoured (iOS is Darwin, Android is Linux), but they might lack a lot of library functions (I haven't got the slightest idea).

Anyway, in any case, to actually get this to compile under macOS, that's the only change you need to do :)

Thanks for all your work on this tool. After experimenting a bit, I've got some clues about why it doesn't work so well with rclone, but the fix is non-trivial (I got as far as getting an "Invalid request" from MEO's web page — better than "authentication failed" which was how far I managed to previously go).

Some other suggestions for you:

1. It would probably be nice if, instead of just showing [Erro], you could be a bit more descriptive in what kind of error was thrown. It would have helped someone unfamiliar with your code to track it down! Even showing the line/file where the error was thrown would be quite helpful.
2. When saving the meocloud.conf file, consider compliance with the XDG Base Directory Specification, which has become increasingly popular to try to handle the (current) mess of everything written under the home directory. Rather — and in the case of your tool — this would mean storing the file as ~/.config/meocloud-upload/meocloud.conf instead. There are very good reasons for this approach, all thoroughly explained in that document 😄

And for the sake of completeness, here go the logs of what I got before changing how OS_UNIX is defined (note how well your code works through a web proxy!):

Log from incorrectly-compiled macOS version

$ meocloud -c ~/.meocloud.conf -v --init
Consumer key: [REDACTED]
Consumer secret: [REDACTED]
Nivel de acesso: Meocloud/Sandbox? [M/s] M
Consumer key introduzida: '[REDACTED]'

Consumer secret introduzido: '[REDACTED]'

Nivel de acesso: Meocloud
Deseja continuar? [s/N] s
Insira o seguinte link no browser e autorize a aplicacao:
https://meocloud.pt/oauth2/authorize?response_type=code&client_id=[REDACTED]
Apos concluir sera apresentado um PIN

Copie este PIN e introduza-o de seguida:
PIN: [REDACTED]

Uses proxy env variable no_proxy == 'localhost,127.0.0.1,localaddress,.localdomain.com'
Uses proxy env variable https_proxy == 'http://[REDACTED]:[REDACTED]/'
Trying [REDACTED]:[REDACTED]...
Connected to [REDACTED] ([REDACTED]) port [REDACTED]
CONNECT tunnel: HTTP/1.1 negotiated
allocate connect buffer
Establish HTTP proxy tunnel to meocloud.pt:443


CONNECT meocloud.pt:443 HTTP/1.1

Host: meocloud.pt:443

User-Agent: meocloud-uploader/1.0

Proxy-Connection: Keep-Alive

< HTTP/1.1 200 Connection established

<

CONNECT phase completed
CONNECT tunnel established, response 200
ALPN: curl offers h2,http/1.1
CAfile: /etc/ssl/certs/ca-certificates.crt
CApath: /etc/ssl/certs
SSL connection using TLSv1.2 / ECDHE-RSA-AES256-GCM-SHA384 / prime256v1 / rsaEncryption
ALPN: server did not agree on a protocol. Uses default.
Server certificate:
subject: C=PT; L=Lisboa; O=MEO - SERVIOS DE COMUNICAES E MULTIMDIA S.A.; CN=*.meocloud.pt
start date: Nov  2 00:00:00 2023 GMT
expire date: Nov  1 23:59:59 2024 GMT
subjectAltName: host "meocloud.pt" matched cert's "meocloud.pt"
issuer: C=US; O=DigiCert Inc; OU=www.digicert.com; CN=DigiCert SHA2 High Assurance Server CA
SSL certificate verify ok.
Certificate level 0: Public key type RSA (2048/112 Bits/secBits), signed using sha256WithRSAEncryption
Certificate level 1: Public key type RSA (2048/112 Bits/secBits), signed using sha256WithRSAEncryption
Certificate level 2: Public key type RSA (2048/112 Bits/secBits), signed using sha1WithRSAEncryption
using HTTP/1.x


POST /oauth2/token?code=[REDACTED]&client_id=[REDACTED]&client_secret=[REDACTED]&redirect_uri=oob&grant_type=authorization_code

HTTP/1.1

Host: meocloud.pt

User-Agent: meocloud-uploader/1.0

Accept: /

Content-Length: 0

Content-Type: application/x-www-form-urlencoded

Expect: 100-continue

< HTTP/1.1 100 Continue

< HTTP/1.1 200 OK

< Server: nginx

< Content-Type: application/json;charset=UTF-8

< Content-Length: 165

< Connection: keep-alive

< x-xss-protection: 1; mode=block

< Content-Language: pt

< Vary: Accept-Language, Cookie

< Pragma: no-cache

< Cache-Control: no-store

< Date: Fri, 19 Jan 2024 17:13:46 GMT

< X-Frame-Options: SAMEORIGIN

< Set-Cookie: sessionid=v03a36fy10295h9mubzq83df5kwgev45; Domain=.meocloud.pt; httponly; Path=/; secure

< Strict-Transport-Security: max-age=31536000

< Cache-Control: no-store

< Pragma: no-cache

<

Connection #0 to host [REDACTED] left intact

-- Start Output --

{"access_token": "[REDACTED]", "token_type": "Bearer", "expires_in": 31536000, "refresh_token": "[REDACTED]", "scope": "ALL"}

--End Output--

Refresh Token: [REDACTED]

Access Token: [REDACTED]
Token recebido expira dentro de 31536000 segundos

[Erro]

$