The shell mime sniffer goes through all the files in a directory,
however in case a file content type is not recognized, the GIO function
g_file_info_get_content_type() may return NULL, causing a crash when
looking up into the content type tables, as they are supposed to contain
strings only and they use `g_str_hash` has func, which doesn't support
NULL values.
So, in case we get an invalid content type, let's just ignore it,
without adding it to the cache as we do in the nautilus code that was
inspiring the sniffer.
Fixes https://gitlab.gnome.org/GNOME/gnome-shell/-/issues/2643
In `st`, we can do this by using `ST_PARAM_*`. In the other code files,
just use `G_PARAM_STATIC_STRINGS` directly.
This is just a minor convenience to prevent a few unnecessary string
copies.
https://gitlab.gnome.org/GNOME/gnome-shell/merge_requests/646
The sniffer is a simple helper process, activated as a DBus service,
that tries to crawl as many files as possible in the provided target
directory (i.e. the new mount's root), for a maximum amount of time -
which is set here to 1.5 seconds (i.e. it will crawl either all the
files in the directory tree, or as many as it can before the specified
timeout expires).
Crawled files are ordered by their content type, and a generic estimation
of the type of files composing the directory is returned to the caller,
using generic 'x-content/*' mimetypes.
The process will then set an autoquit timeout on itself, which can be
disabled by setting the env variable HOTPLUG_SNIFFER_PERSIST for
debugging purposes. The HOTPLUG_SNIFFER_DEBUG env variable can also be
set to enable debugging output.
https://bugzilla.gnome.org/show_bug.cgi?id=653520
