Input method in FreeBSD virtual terminal (Week7)

Date: 07/19-07/25

At the beginning of this week I did some experiments with vt_processkey() and terminal_input_char(), such as a function that recieves a key and echos back.

After figuring out the usage of the two functions, I hijacked vt_processkey() function and use right CTRL key to toggle the rime mode. If the rime mode is enabled, the key will be passed into the custom function called vt_rime_process_char() to send the key to the rime server.

Now, the most important problem is how to communicate with the rime server. I list some requirements for implementation:

1. The kernel need to send character to the Rime server in user space when receiving keyboard events.
2. The Rime server replies CJK characters. Additionally, word candidates and preedit string.
3. The kernel output the characters to where the cursor is and display candidates and preedit string.

Another issue is the default VT font does not contain Chinese characters, so I am unable to insert/display CJK characters on the screen. Fortunately, my mentor LiWenHsu told me there is a usable font that supports CJK chars in fontstuff repo.

• Try out the b16.hex in fontstuff repo to check it can display CJK or even bopomofo chars
• Take a look at route(4) (route monitor) to see how it achieves the communication between kernel and user mode:
  • user mode: src/sbin/route/route.c
  • kernel mode: sys/net/rtsock.c