When an empty string is given to OSC7, the pwd is reset to nil (as if
the terminal never received a pwd report to begin with). This is
analogous to how OSC0/2 reset the title to nil when given an empty
string.
This is practically useful for macOS because it allows our proxy icon to
also be reset instead of being stuck on the last known path.
This breaks from any known terminal behavior. As far as I can find, this
is totally unspecified so we're somewhat free to do what we want. I
don't think any terminal programs depend on this behavior, so I think
it's safe to change it.
Fixes#2651
First, our OSC parser didn't allow blank OSC 0 or 2 requests. This
should be allowed and this fixes that with a test.
Second, it seems many terminals (iTerm2, Kitty) treat setting a blank
title as resetting to whatever the default title is rather than
explicitly setting it as blank. If a program wants a title to be blank
they should send a single space. This commit follows this behavior.
The explanation now refers to RFC 793 instead of just claiming some
arbitrary value as truth. The previous value was correct, but now there
is a proper source for the correct value.
When the focus reporting mode (1004) is enabled, send the current focus
state. This allows applications to track their own focus state without
first having to wait for a focus event (or query
it by sending a DECSET followed by a DECRST).
Ghostty's focus state is stored only in the renderer, where the termio
thread cannot access it. We duplicate the focus state tracking in the
Terminal struct with the addition of a new (1-bit) flag. We duplicate
the state because the renderer uses the focus state for its own purposes
(in particular, the Metal renderer uses the focus state to manage
its DisplayLink), and synchronizing access to the shared terminal state
is more cumbersome than simply tracking the focus state in the renderer
in addition to the terminal.
- Cap the total number of requests at twice the maximum number of
keys (currently 263, so 526 requests). Basically you can set and then
query every key in one message. This is an absurdly high number
but should prevent serious DOS attacks.
- Clarify meaning of new hex color codes.
- Better handle sending messages to the renderer in a way that should
prevent deadlocks.
- Handle 0-255 palette color requests by creatively using non-exhautive
enums.
- Fix an error in the query reply.
Kitty 0.36.0 added support for a new OSC escape sequence for
quering, setting, and resetting the terminal colors. Details
can be found [here](https://sw.kovidgoyal.net/kitty/color-stack/#setting-and-querying-colors).
This fully parses the OSC 21 escape sequences, but only supports
actually querying and changing the foreground color, the background
color, and the cursor color because that's what Ghostty currently
supports. Adding support for the other settings that Kitty supports
changing ranges from easy (cursor text) to difficult (visual bell,
second transparent background color).
These sequences were implemented:
CSI 14 t - report the text area size in pixels
CSI 16 t - report the cell size in pixels
CSI 18 t - report the text area size in cells
CSI 21 t - report the window title
These sequences were not implemented because they manuipulate the window
state in ways that we do not want.
CSI 1 t
CSI 2 t
CSI 3 ; x ; y t
CSI 4 ; height ; width ; t
CSI 5 t
CSI 6 t
CSI 7 t
CSI 8 ; height ; width ; t
CSI 9 ; 0 t
CSI 9 ; 1 t
CSI 9 ; 2 t
CSI 9 ; 3 t
CSI 10 ; 0 t
CSI 10 ; 1 t
CSI 10 ; 2 t
CSI 24 t
These sequences were not implemented because they do not make sense in
a Wayland context:
CSI 11 t
CSI 13 t
CSI 14 ; 2 t
These sequences were not implemented because they provide information
about the screen that is unnecessary.
CSI 15 t
CSI 19 t
These sequences were not implemeted because Ghostty does not maintain an
icon title for windows.
CSI 20 t
CSI 22 ; 0 t
CSI 22 ; 1 t
CSI 23 ; 0 t
CSI 23 ; 1 t
These sequences were not implemented because of the additional
complexity of maintaining a stack of window titles.
CSI 22 ; 2 t
CSI 23 ; 2 t
When set, the cursor-invert-fg-bg option uses the inverted foreground
and background colors of the cursor's current cell to color the cursor,
rather than using a fixed color. This option has higher precedence than
the cursor-color and cursor-text options, but has lower precedence than
an OSC 12 command to change the cursor color.
