adds ability to specify user and password via env variables

src/cmd/cmd.cpp

@@ -1,11 +1,12 @@
 /*
  * SPDX-FileCopyrightText: 2017 Nextcloud GmbH and Nextcloud contributors
  * SPDX-FileCopyrightText: 2014 ownCloud GmbH
  * SPDX-License-Identifier: GPL-2.0-or-later
  */
 
+#include <cstdlib>
 #include <iostream>
 #include <qcoreapplication.h>
 #include <QStringList>
 #include <QUrl>
 #include <QFile>
@@ -174,7 +175,7 @@
     std::cout << "  --user, -u [name]      Use [name] as the login name" << std::endl;
     std::cout << "  --password, -p [pass]  Use [pass] as password" << std::endl;
     std::cout << "  -n                     Use netrc (5) for login" << std::endl;
-    std::cout << "  --non-interactive      Do not block execution with interaction" << std::endl;
+    std::cout << "  --non-interactive      Do not block execution with interaction and tries to read $NC_USER and $NC_PASSWORD if not set by other means" << std::endl;
     std::cout << "  --max-sync-retries [n] Retries maximum n times (default to 3)" << std::endl;
     std::cout << "  --uplimit [n]          Limit the upload speed of files to n KB/s" << std::endl;
     std::cout << "  --downlimit [n]        Limit the download speed of files to n KB/s" << std::endl;
@@ -296,7 +297,7 @@
     }
 }
 
 int main(int argc, char **argv)
 {
 #ifdef Q_OS_WIN
     SetDllDirectory(L"");
@@ -351,6 +352,7 @@
     // 2. From options
     // 3. From netrc (if enabled)
     // 4. From prompt (if interactive)
+    // 5. From environment (if non-interactive)
 
     QString user = hostUrl.userName();
     QString password = hostUrl.password();
@@ -382,7 +384,15 @@
         if (password.isEmpty()) {
             password = queryPassword(user);
         }
+    } else {
+        if (user.isEmpty()) {
+            user = QString::fromUtf8(qgetenv("NC_USER"));
+        }
+        if (password.isEmpty()) {
+            password = QString::fromUtf8(qgetenv("NC_PASSWORD"));
+        }
     }
+
 
     // Find the folder and the original owncloud url