Re: [PATCH v1 6/6] Documentation: Describe console mouse reporting

2020-06-30 Thread Randy Dunlap
Hi--

(duplicating some of Juri's comments)

On 6/30/20 12:12 AM, Tammo Block wrote:
> This patch adds a description of the kernel interface(s) used for vt
> console mouse reporting and describes the protocols and bitmasks.
> 
> Signed-off-by: Tammo Block 
> ---
>  .../admin-guide/console-mouse-reporting.rst   | 92 +++
>  Documentation/admin-guide/index.rst   |  1 +
>  2 files changed, 93 insertions(+)
>  create mode 100644 Documentation/admin-guide/console-mouse-reporting.rst
> 
> diff --git a/Documentation/admin-guide/console-mouse-reporting.rst 
> b/Documentation/admin-guide/console-mouse-reporting.rst
> new file mode 100644
> index ..11287cb233ba
> --- /dev/null
> +++ b/Documentation/admin-guide/console-mouse-reporting.rst
> @@ -0,0 +1,92 @@
> +.. SPDX-License-Identifier: GPL-2.0
> +
> +===
> +Console Mouse Reporting
> +===
> +
> +A terminal may send escape sequences to enable applications to react to mouse
> +input. As the kernel does not know when to emit these events a mouse daemon
> +is needed to react to mouse movements and signal the kernel accordingly. The
> +kernel will then send an escape sequence to the application. This is called
> +mouse reporting and several types and protocols have been developed over 
> time.
> +
> +See tiocl.h, the :manpage:`ioctl_console(2)` and :manpage:`console_codes(4)`
> +man pages and the xterm [1]_ or terminalguide [2]_ home pages for a detailed
> +list and description of the various protocols, their bit layout as well as
> +their limitations.
> +
> +Events and formats
> +++
> +
> +A linux console keeps state about two different aspects of mouse reporting,

 Linux

> +the kind of **events** to be reported and the **format** to send to 
> userspace.
> +
> +A mouse daemon can check which kind of mouse events a clients wants to be

 client

> +informed about via the TIOCLINUX ioctl, using the TIOCL_GETMOUSEREPORTING
> +subcall. The values of the supported event classes (9, 1000, 1002, 1003) are
> +described in tiocl.h. Based on this information the daemon is responsible
> +for not sending data packages for unrequested events.
> +
> +A userspace client may request to be informed by the kernel about one of
> +the event classes and chose one of the data formats URXVT (1005), SRG

 choose

> +(1006) or X10/X11 (default) via console escape sequences. In general all
> +of them encode similar information, only the escape sequences differ.
> +
> +See the xterm [1]_ or terminalguide [2]_ home pages for all details.
> +
> +Reports from kernel to userspace client
> 
> +
> +The requested events are sent by the kernel to userspace encoded in a

   an

> +escape sequence, details depend on the chosen format. All of them use one

  sequence; details

> +based pointer coordinates and a single byte to encode the button status.
> +
> +Short summary (we call this the SRG button format for the rest of this text):
> +
> + - 1,2 : Buttons, lower bits (see notes below)
> + - 3-5 : Modifier keys (Shift, Alt and Ctrl)
> + - 6   : Mouse movement only, no button status change
> + - 7-8 : Buttons, upper bits (for buttons 4-15)
> +
> +Reports send from daemon to kernel

   sent

> +++
> +
> +A report is send by a mouse daemon to the kernel via the TIOCLINUX ioctl,

   sent

> +using the TIOCL_SETSEL subcall. The coordinates are encoded zero based in
> +xs and ys, with 0,0 as upper left corner, but see note below.
> +The format used by the userspace mouse daemon for button encoding is almost
> +identical to the SRG button layout decribed above and is put into the 
> sel_mode

  described

> +of the tiocl_selection struct. All bits masked in TIOCL_SELBUTTONMASK are
> +unchanged compared to the SRG button format above, the remaining three are

   above; the

> +changed the following way :
> +
> +- 3,4  : Unused, must be zero. The kernel knows modifier key state anyway.
> +- 5: Always 1, identifies mouse report / TIOCL_SELMOUSEREPORT
> +
> +Notes
> ++
> +
> +Button numbers are encoded like this:
> +
> +- 0-2  : Left, middle and right button
> +- 3: No button pressed / Button release
> +- 4-15 : More buttons, e.g. 4 and 5 are scroll wheel
> +
> +Please note that button releases should only be reported for buttons 0-2.
> +
> +Also note that coordinates (xs,ys,xe,ye) are zero based for the TIOCL_SETSEL
> +syscall but one based for the escape sequences sent by the kernel, so the
> +kernel will increase all coordinates by one.
> +
> +Older kernels only used the lower 4 bits of sel_mode, effectively limiting
> +the protocol to 3 buttons and button click only. The meaning of 

Re: [PATCH v1 6/6] Documentation: Describe console mouse reporting

2020-06-30 Thread Jiri Slaby
Cc Randy who commented on v0 (you should have done it).

On 30. 06. 20, 9:12, Tammo Block wrote:
> This patch adds a description of the kernel interface(s) used for vt
> console mouse reporting and describes the protocols and bitmasks.
> 
> Signed-off-by: Tammo Block 
> ---
>  .../admin-guide/console-mouse-reporting.rst   | 92 +++
>  Documentation/admin-guide/index.rst   |  1 +
>  2 files changed, 93 insertions(+)
>  create mode 100644 Documentation/admin-guide/console-mouse-reporting.rst
> 
> diff --git a/Documentation/admin-guide/console-mouse-reporting.rst 
> b/Documentation/admin-guide/console-mouse-reporting.rst
> new file mode 100644
> index ..11287cb233ba
> --- /dev/null
> +++ b/Documentation/admin-guide/console-mouse-reporting.rst
> @@ -0,0 +1,92 @@
> +.. SPDX-License-Identifier: GPL-2.0
> +
> +===
> +Console Mouse Reporting
> +===
> +
> +A terminal may send escape sequences to enable applications to react to mouse
> +input. As the kernel does not know when to emit these events a mouse daemon
> +is needed to react to mouse movements and signal the kernel accordingly. The
> +kernel will then send an escape sequence to the application. This is called
> +mouse reporting and several types and protocols have been developed over 
> time.
> +
> +See tiocl.h, the :manpage:`ioctl_console(2)` and :manpage:`console_codes(4)`
> +man pages and the xterm [1]_ or terminalguide [2]_ home pages for a detailed
> +list and description of the various protocols, their bit layout as well as
> +their limitations.
> +
> +Events and formats
> +++
> +
> +A linux console keeps state about two different aspects of mouse reporting,
> +the kind of **events** to be reported and the **format** to send to 
> userspace.
> +
> +A mouse daemon can check which kind of mouse events a clients wants to be

client

> +informed about via the TIOCLINUX ioctl, using the TIOCL_GETMOUSEREPORTING
> +subcall. The values of the supported event classes (9, 1000, 1002, 1003) are
> +described in tiocl.h. Based on this information the daemon is responsible
> +for not sending data packages for unrequested events.
> +
> +A userspace client may request to be informed by the kernel about one of
> +the event classes and chose one of the data formats URXVT (1005), SRG
> +(1006) or X10/X11 (default) via console escape sequences. In general all
> +of them encode similar information, only the escape sequences differ.
> +
> +See the xterm [1]_ or terminalguide [2]_ home pages for all details.
> +
> +Reports from kernel to userspace client
> 
> +
> +The requested events are sent by the kernel to userspace encoded in a

an

> +escape sequence, details depend on the chosen format. All of them use one
> +based pointer coordinates and a single byte to encode the button status.
> +
> +Short summary (we call this the SRG button format for the rest of this text):
> +
> + - 1,2 : Buttons, lower bits (see notes below)
> + - 3-5 : Modifier keys (Shift, Alt and Ctrl)
> + - 6   : Mouse movement only, no button status change
> + - 7-8 : Buttons, upper bits (for buttons 4-15)
> +
> +Reports send from daemon to kernel

sent

> +++
> +
> +A report is send by a mouse daemon to the kernel via the TIOCLINUX ioctl,

sent (Randy pointed out this one already)

> +using the TIOCL_SETSEL subcall. The coordinates are encoded zero based in
> +xs and ys, with 0,0 as upper left corner, but see note below.

I think "the" is missing twice in that sentence, but leave it as is
unless some native speaker confirms.

> +The format used by the userspace mouse daemon for button encoding is almost
> +identical to the SRG button layout decribed above and is put into the 
> sel_mode

described

> +of the tiocl_selection struct. All bits masked in TIOCL_SELBUTTONMASK are
> +unchanged compared to the SRG button format above, the remaining three are
> +changed the following way :

no space belongs before colons, here in Europe.

> +
> +- 3,4  : Unused, must be zero. The kernel knows modifier key state anyway.
> +- 5: Always 1, identifies mouse report / TIOCL_SELMOUSEREPORT
> +
> +Notes
> ++
...

thanks,
-- 
js
suse labs


[PATCH v1 6/6] Documentation: Describe console mouse reporting

2020-06-30 Thread Tammo Block
This patch adds a description of the kernel interface(s) used for vt
console mouse reporting and describes the protocols and bitmasks.

Signed-off-by: Tammo Block 
---
 .../admin-guide/console-mouse-reporting.rst   | 92 +++
 Documentation/admin-guide/index.rst   |  1 +
 2 files changed, 93 insertions(+)
 create mode 100644 Documentation/admin-guide/console-mouse-reporting.rst

diff --git a/Documentation/admin-guide/console-mouse-reporting.rst 
b/Documentation/admin-guide/console-mouse-reporting.rst
new file mode 100644
index ..11287cb233ba
--- /dev/null
+++ b/Documentation/admin-guide/console-mouse-reporting.rst
@@ -0,0 +1,92 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+===
+Console Mouse Reporting
+===
+
+A terminal may send escape sequences to enable applications to react to mouse
+input. As the kernel does not know when to emit these events a mouse daemon
+is needed to react to mouse movements and signal the kernel accordingly. The
+kernel will then send an escape sequence to the application. This is called
+mouse reporting and several types and protocols have been developed over time.
+
+See tiocl.h, the :manpage:`ioctl_console(2)` and :manpage:`console_codes(4)`
+man pages and the xterm [1]_ or terminalguide [2]_ home pages for a detailed
+list and description of the various protocols, their bit layout as well as
+their limitations.
+
+Events and formats
+++
+
+A linux console keeps state about two different aspects of mouse reporting,
+the kind of **events** to be reported and the **format** to send to userspace.
+
+A mouse daemon can check which kind of mouse events a clients wants to be
+informed about via the TIOCLINUX ioctl, using the TIOCL_GETMOUSEREPORTING
+subcall. The values of the supported event classes (9, 1000, 1002, 1003) are
+described in tiocl.h. Based on this information the daemon is responsible
+for not sending data packages for unrequested events.
+
+A userspace client may request to be informed by the kernel about one of
+the event classes and chose one of the data formats URXVT (1005), SRG
+(1006) or X10/X11 (default) via console escape sequences. In general all
+of them encode similar information, only the escape sequences differ.
+
+See the xterm [1]_ or terminalguide [2]_ home pages for all details.
+
+Reports from kernel to userspace client

+
+The requested events are sent by the kernel to userspace encoded in a
+escape sequence, details depend on the chosen format. All of them use one
+based pointer coordinates and a single byte to encode the button status.
+
+Short summary (we call this the SRG button format for the rest of this text):
+
+ - 1,2 : Buttons, lower bits (see notes below)
+ - 3-5 : Modifier keys (Shift, Alt and Ctrl)
+ - 6   : Mouse movement only, no button status change
+ - 7-8 : Buttons, upper bits (for buttons 4-15)
+
+Reports send from daemon to kernel
+++
+
+A report is send by a mouse daemon to the kernel via the TIOCLINUX ioctl,
+using the TIOCL_SETSEL subcall. The coordinates are encoded zero based in
+xs and ys, with 0,0 as upper left corner, but see note below.
+The format used by the userspace mouse daemon for button encoding is almost
+identical to the SRG button layout decribed above and is put into the sel_mode
+of the tiocl_selection struct. All bits masked in TIOCL_SELBUTTONMASK are
+unchanged compared to the SRG button format above, the remaining three are
+changed the following way :
+
+- 3,4  : Unused, must be zero. The kernel knows modifier key state anyway.
+- 5: Always 1, identifies mouse report / TIOCL_SELMOUSEREPORT
+
+Notes
++
+
+Button numbers are encoded like this:
+
+- 0-2  : Left, middle and right button
+- 3: No button pressed / Button release
+- 4-15 : More buttons, e.g. 4 and 5 are scroll wheel
+
+Please note that button releases should only be reported for buttons 0-2.
+
+Also note that coordinates (xs,ys,xe,ye) are zero based for the TIOCL_SETSEL
+syscall but one based for the escape sequences sent by the kernel, so the
+kernel will increase all coordinates by one.
+
+Older kernels only used the lower 4 bits of sel_mode, effectively limiting
+the protocol to 3 buttons and button click only. The meaning of the 4 bits
+is equivalent to the SRG button layout. Note that newer kernel will ignore
+the upper two bits (modifier keys).
+
+.. [1] 
https://invisible-island.net/xterm/ctlseqs/ctlseqs.html#h2-Mouse-Tracking
+.. [2] https://terminalguide.namepad.de/mouse/
+
+
+
+
+
diff --git a/Documentation/admin-guide/index.rst 
b/Documentation/admin-guide/index.rst
index 58c7f9fc2396..c535902f3851 100644
--- a/Documentation/admin-guide/index.rst
+++ b/Documentation/admin-guide/index.rst
@@ -71,6 +71,7 @@ configure specific aspects of kernel behavior to your liking.
cgroup-v2
cifs/index
clearing-warn-once
+   console-mouse-reporting
cpu-load