Bareline

Bareline is a command line interface (CLI) framework. It doesn't depend on other libraries. It doesn't allocate from data or BSS sections. It can be easily brought up on bare metal environments.

Highlights

Easy to port
Line editing
History
Extensible command
Complete
Hint
VT100 compatible

Tested environments

GCC 5.4.0 + Ubuntu 16.04.5 LTS
GCC 4.8.5 + Proprietary MIPS board
GCC 8.25 + Raspberry Pi 3 B+

Build and run example for Ubuntu

make PLAT=plat_ubuntu all
./bin/demo.out

Build example for MIPS

plat_mips assumes an 16550 compatible UART, and RAM starts from 0x80000000.

CROSS_COMPILE=<prefix of mips toolkit> UART_BASE_ADDR=<base addr.> make PLAT=plat_mips all

Then load ./bin/demo.out to run.

Build example for RPi3

make PLAT=plat_rpi3 all

Then load ./bin/demo.out to RPi3 to run.

Porting Bareline

Bareline has no dependency to other libraries. This makes porting Bareline fairly easy. Implementing your own bl_putc() and bl_getc() is enough to make Bareline works. To start Bareline, one just invokes bl_main_loop() with buffer pointer, buffer size, and line length. Bareline doesn't allocate from data and BSS sections. It relies on its caller to provide necessary memory space. Check ./plat_ubuntu/bareline_example.c for an example.

Operations

Bareline supports moving cursor left and right. Backspace, delete, and insert characters are also supported. Every entered line is kept in a circular history buffer. One can traverse available history lines with up and down. Bareline comes with some common key bindings:

Key	Description
`ctrl` + `a`	move cursor to head of line
`ctrl` + `b`	move cursor left
`ctrl` + `c`	exit Bareline
`ctrl` + `d`	delete char. to the right of cursor
`ctrl` + `e`	move cursor to end of line
`ctrl` + `f`	move cursor right
`ctrl` + `k`	delete char. from the cursor through the end of the line
`ctrl` + `n`	get newer history
`ctrl` + `p`	get older history

Extensible command

Bareline provides a macro BL_REG_CMD() to expand commands in Bareline. For example,

BL_REG_CMD(exit, do_exit, "exit bareline");

registers a command, exit, to Bareline. When exit is entered, Bareline invokes do_exit() for response. And finally, "exit bareline" is the message to be showed for help command. Check ./src/bareline_builtin.c for more examples.

Complete and hint

Bareline supports complete and hint when typing a command, as long as the command is registered by BL_REG_CMD().

Given a partial command followed by enter, Bareline executes it directly if it can be distinguished. Otherwise Bareline does nothing.

Given a partial command followed by tab, Bareline completes it in line buffer if it can be distinguished and unique. If it is ambiguous, Bareline lists all candidates. Otherwise Bareline does nothing.

Acknowledgments

Bareline uses printf by mpaland/printf@21eea6c.

Bareline uses xmodem by Thuffir/xmodem@8ca6c42.

jiajheli/bareline