The size of size_t depends on the architecture, so we need to have
different conversion to and from strings. But we don't really need that
range, so avoid the issue by using a standard integer size.

It should return a path to the directory itself, just like its sister
function getuserhomedir().

All library functions should be in a proper namespace.

This mimics how some system functions (like inet_ntop()) work, and
avoids complexity around ownership of the returned string buffer.

The downside is that the string must be consumed directly as it will be
overwritten on the next call, but that is not an issue with the current
usage.

We never use Windows' "UNICODE" mode anyway, so let's get rid of this
complexity.

Try to be more consistent that related options should have a group box
around them.

This is what pretty much everyone else calls these kind of settings, so
let's change so users feel familiar.

Try to focus on the commonly used settings here in order to keep things
understandable. The uncommon settings will need to be specified as
command line arguments instead.

Clarify what this list is used for, and organize it so it is easier to
match to the options dialog.

Previously, there were a number of inconsistencies in the use of
"full-screen" and "full screen" in logs, documentation, and user
interfaces. The consensus seems to be that "full screen" is correct when
used as a noun while "full-screen" is correct when used as an
adjective. These inconsistencies have now been adjusted to follow
consensus.

Try to reuse and split things so that it makes things easier for the
translators.

Clean up the structure around storing and loading parameters and server
history so that failures will always be reported by using exceptions.

If the file has been transferred from a Windows system then it might
have \r\n line endings instead of \n. Make sure this doesn't leak in to
the parameter values.

The user might not always want to use all monitors when in fullscreen
mode, but instead only a few. This commit adds support for configuring
selected monitors from command line, in the config file and graphically
in the options menu.

Because it might be hard to guarantee the consistency of monitor
identifiers coming from third-parties (for example FLTK), it has been
decided to use our own numerical identifier. This identifier is based on
the monitor's positions. The mapping between this identifier and the
indices used by FLTK is done by MonitorIndicesParameter.

Before this commit, `FullScreen` and `FullScreenAllMonitors` could be
used to configure whether to use the current monitor in fullscreen,
or all monitors in fullscreen.

This commit deprecates `FullScreenAllMonitors` in favour of
`FullScreenMode` (which can either be `current` or `all`). This allows
for additional modes to be added, without the risk of having invalid
states (for example two activate two different fullscreen modes at the
same time).

A new concept has been added; read-only parameters. They are parameters
that will be read, but never written back. This allows for migration
paths to be constructed, where a parameter can be taken to consideration
but then for example be discarded, logged or changed into something else.

This has been used for `FullScreenAllMonitors` to provide a migration
path. On startup of vncviewer, if `FullScreenAllMonitors` is enabled,
`FullScreenMode=all` will be automatically enabled instead. The next
time the configuration file is written to disk, `FullScreenAllMonitors`
will then be removed.

Not every mouse has three buttons e.g. laptops. Some OS might not
have support for middle mouse button emulation.

This commit adds emulation for middle mouse button when pressing both
left and right mouse button simultaneously.

Commit 4e61f8dbc5 fixed the GUI but forgot
to change the other places in the code.

The number of colors used isn't something the end-users should have to
concern themselves with. I intentionally left the information in the
man-pages.

The parameter files are used to make sure changes in the UI are
persistent. Storing anything else results in behaviours that the
user has no easy way of changing.

It is already hidden in the UI, so make sure it also is gone as a
command line parameter. This follows the behaviour of the similar
sendPrimary parameter.

These are not allowed in C++, and have been made optional in C11.
So let's just get rid of them and any issues they may cause.

The user might just want to load a bunch of settings and not
initiate a connection.

Make the code simpler by handling it just like any escaped character.

We decoded "\\n" as "n" rather than "\n".

Fl::arg accepts several arguments which we are not documenting. Also,
it accepts a -geometry argument, which clashes with our own -geometry
option.

Some systems (e.g. macOS) send massive amounts of pointer events, so
we need to start rate limiting things to something sensible by default.
One event per screen refresh should be more than sufficient.

Add a new parameter 'alertOnFatalError' which guards
the displaying of the GUI alert on fatal errors, and
thus when false just gives the textual error.

Now I can do:

  while true
  do
    vncviewer alertOnFatalError=false vm:0
    sleep 1
  done

and it'll reappear when my VM appears without me getting error
dialogs.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
--

We haven't supported them in a long time so we shouldn't mention
them in the interface and documentation.

Previously the incoming clipboard was unconditionally set to both
the PRIMARY and CLIPBOARD selection. This isn't always what the
user want, so make it configurable.

Primary selection is inherently a X11 concept so there is no point
showing the settings related to it on other platforms.

Either by casting, or switching to a more appropriate type
for the variable.

This means that we can remove a lot of conditionals and fallback code.

There is no need for these to be global symbols as they are only
used in that file.

They were not very end user friendly so redo more or less all of them.