Add a new way to detect where the Tesseract data are stored in a user's
system. On Linux, the Tesseract data should be installed via the package
manager. On macOS and Windows, they should be bundled with the
Dangerzone application.
There is also the exception of running Dangerzone locally, where even
on Linux, we should get the Tesseract data from the Dangerzone share/
folder.
In d632908a44 we improved our
`replace_control_chars()` function, by replacing every control or
invalid Unicode character with a placeholder one. This change, however,
made our debug logs harder to read, since newlines were not preserved.
There are indeed various cases in which replacing newlines is wise
(e.g., in filenames), so we should keep this behavior by default.
However, specifically for reading debug logs, we add an option to keep
newlines to improve readability, at no expense to security.
The `util.replace_control_chars()` function was overly strict, and
would replace every non-ASCII character with "_". This included both
control characters, as well as normal characters in a non-English
alphabet.
Relax these restrictions by checking each character and deciding if it's
a Unicode control character, using the `unicodedata` Python package.
With this change, emojis and non-English letters are now allowed.
This reverts commit fea193e935.
This is part of the purge of timeout-related code since we no longer
need it [1]. Non-blocking reads were introduced in the reverted commit
in order to be able to cut a stream mid-way due to a timeout. This is
no longer needed now that we're getting rid of timeouts.
[1]: https://github.com/freedomofpress/dangerzone/issues/687
Do not store temporary directories in the Dangerzone's config directory.
There are two reasons for that:
1. They are ephemeral, and they need a temporary place to be stored,
preferably RAM-backed.
2. We need to set them while running our CI tests.
- display_banner() was only displayed in CLI mode so it makes sense
for it to be in the CLI.
- get_version(), was mvoed to util since it is a static function
that is needed in multiple parts of the application.
static methods that are used application-wide should belong to
the utilities python file.
inspired by @gmarmstrong's PR #166 on refactoring global_common
methods to be static and have a dzutil.py
