neogdb.vim

Vim GDB front-end for neovim: https://github.com/huawenyu/new-gdb.vim
Prerequire: Must install new.vim plugin first.

Quickstart

### Suppose we use [vim-plug](https://github.com/junegunn/vim-plug)
### And already we add the plug to our `.vimrc`
    Plug 'huawenyu/new.vim', Cond(has('nvim')) | Plug 'huawenyu/new-gdb.vim', Cond(has('nvim'))
### And install the plug
    vi's command: ":PlugInstall"

### So the following dir exist: 
$ cd ~/.vim/bundle/new-gdb.vim
$ cd autoload/examples
$ ls
    t1.c
$ gcc -g -O0 -o t1 t1.c
$ vi t1.c
[vim-command-mode] ":Nbgdb t1"
Focus the source code t1.c windows, and Press:
  F5   next
  S-F5 skip
  F6   step
  S-F6 return to caller
  F8   eval current value
<end>

feature

• gdb commands maps: next, step, finish, continue, etc.
• breakpoints:
  • auto save/load,
  • populate to local list: lopen
  • side color sign
  • triple state: enable -> disable -> delete
  • toggle current line/toggle-all-breakpoints
  • support condition set
• backtrace:
  • populate to quickfix: copen

layout

+-------------------------+--------------------------+
|                         |                          |
|                         |                          |
|                         |                          |
|                         |    terminal>             |
|     Code c/c++          |    (gdb)                 |
|                         |                          |
|                         |                          |
|                         |                          |
|                         |                          |
|                         +--------------------------+
|                         |                          |
+-------------------------+  backtrace               |
| breakpoints             |                          |
|                         |                          |
+-------------------------+--------------------------+

Screen Demo

Press to toggle Nbgdb or Nbgdbattach.

gdb directly

:Nbgdb t1

gdb attach pid

So far, the attach call by sudo, so maybe we should input the sudo-password. The reason is: gdb-attach-fails-with-ptrace-operation-not-permitted

:Nbgdbattach t1 <t1-pid>

gdb remote target

:Nbgdbattach sysinit/init localhost:9999

gif

Install

Install if no any plugin manager

The file structure should be clear, just copy the github.vim into ~/.vim/plugin/

Installing when using Vundle

Add the following line to the plugins regions of ~/.vimrc:

Plug 'huawenyu/new.vim', Cond(has('nvim')) | Plug 'huawenyu/new-gdb.vim', Cond(has('nvim'))

Usage

commands

• :GdbLocal
• :GdbDebugStop
• :GdbToggleBreakpoint
• :GdbClearBreakpoints
• :GdbContinue
• :GdbNext
• :GdbStep
• :GdbFinish
• :GdbFrameUp
• :GdbFrameDown
• :GdbInterrupt
• :GdbEvalWord
• :GdbWatchWord

Default keymaps

• <F2> Helper Start
• <F3> refresh and re-locate current line
• <F4> continue
• <Shift+F4> stop
• <F5> next
• <Shift+F5> just skip one line and not execute it
• <F6> step
• <Shift+F6> finish current function and return to the caller
• <F7> continue execute util this line
• <F8> eval current member or eval the selected expression
• <Shift+F8> watch current member or watch the selected expression
• <F9> toggle the current breakpoint
• <F10> toggle all breakpoints

Sample

There have a c file autoload/examples/t1.c in the plugin's dir. Please copy it to your test dir.

    ### compile test
    $ cd /dir/of/file/t1.c
    $ gcc -g -O0 -o t1 t1.c
    ### start gdb
    $ vi t1.c
      If default keymap, <F2>, the command line show `:Nbgdb t1`, <Enter> to start gdb.

Customization

Put these in your ~/.vimrc to customize the keymaps:

keymaps leader

If define g:neobugger_leader, will ignore all g:gdb_keymap_... customized.

let g:neobugger_leader = ';'

Then the keymaps will be g:neobugger_leader + <char>, the <char> like:

• r: GdbRefresh
• c: GdbContinue
• n: GdbNext
• i: GdbStep
• N: GdbFinish
• t: GdbUntil
• b: GdbToggleBreak
• a: GdbToggleBreakAll
• C: GdbClearBreak
• x: GdbDebugStop
• k: GdbFrameUp
• j: GdbFrameDown

keymaps without leader

" Howto map Shift+F#:
"   - Goto insert mode and hit Ctrl-V Shift-F#, which gotted we can use that to map.
"   - For example: We get "<F15>" when input Shift+F5, so ':nmap <F15> echo "HELLO"<cr>' should be work.
" The default config:
"
let g:gdb_keymap_refresh = '<f3>'

let g:gdb_keymap_continue = '<f4>'
let g:gdb_keymap_debug_stop = '<F14>'

let g:gdb_keymap_next = '<f5>'
let g:gdb_keymap_skip = '<F15>'

let g:gdb_keymap_step = '<f6>'
let g:gdb_keymap_finish = '<F16>'

let g:gdb_keymap_until = '<f7>'

let g:gdb_keymap_eval = '<f8>'
let g:gdb_keymap_watch = '<F18>'

let g:gdb_keymap_toggle_break = '<f9>'
let g:gdb_keymap_remove_break = '<F19>'

let g:gdb_keymap_toggle_break_all = '<f10>'
let g:gdb_keymap_clear_break = '<F20>'

let g:gdb_keymap_frame_up = '<c-n>'
let g:gdb_keymap_frame_down = '<c-p>'
let g:neogdb_gdbserver = 'gdbserver'
let g:neogdb_attach_remote_str = 't1 127.0.0.1:9999'
let g:gdb_auto_run = 1
let g:gdb_require_enter_after_toggling_breakpoint = 0
let g:restart_app_if_gdb_running = 1
let g:neobugger_smart_eval = 0
let g:neobugger_local_breakpoint = 0
let g:neobugger_local_backtrace = 0
let g:neobugger_server_breakpoint = 1
let g:neobugger_server_backtrace = 1

Miscellaneous

config windows

Current implement only support two kinds of windows: backtrace, breakpoint. The default config is:

• local-mode, diable these windows
• attach-mode, open them

But we can modify the default bahaviour by config:

let g:neogdb_window = ['backtrace', 'breakpoint']

Customize attach parameter

The Nbgdbattach always use target remote to connect a real searver which is different in everyone's env.
So we can specific a local host by put these into .vimrc:

if exists("$NBG_ATTACH_REMOTE_STR")
  let g:neogdb_attach_remote_str = $NBG_ATTACH_REMOTE_STR
else
  let g:neogdb_attach_remote_str = 'sysinit/init 127.0.0.1:9999'
endif

Or define a env var NBG_ATTACH_REMOTE_STR by putting in .bashrc:

export NBG_ATTACH_REMOTE_STR="sysinit/init 127.0.0.1:9999"

Enable restart

By default, if you run Nbgdb or Nbgdbattach when GDB is already started,
the plugin will send an interrupt (<c-c>) followed by a start.
This is in order to speed up the edit-compile-test cycle.
If you instead want an error to be thrown when GDB is already started, change this variable:

let g:restart_app_if_gdb_running = 0

By default, the plugin toggles the breakpoint right after pressing g:gdb_keymap_toggle_break.
If this flag is set to 1, the plugin will require you to confirm the command with Enter which lets you edit the command before issuing it:

others

let g:gdb_require_enter_after_toggling_breakpoint = 0

To send your own commands to GDB:

" Prints the value of the variable under the cursor
nmap <Space>p :call neobugger#gdb#Send("print " . expand('<cword>'))<CR>

Map and unmap callbacks

You can run your own code when Neogdb sets its keymaps.
The plugin will call NeogdbvimNmapCallback on initialization and NeogdbvimUnmapCallback on exiting, if these functions exist.

For example, you can put this in your ~/.vimrc:

function! NeogdbvimNmapCallback()
    " Let fzf.vim open files in the current window by default.
    " This is so that, when navigating files,
    " we don't switch to a new tab and thus *always* see the neogdb's splits. 
    let g:fzf_action = { 'enter': 'edit' }
endfunc

function! NeogdbvimUnmapCallback()
    " Quitting to normal editing. Let fzf.vim open files in the new tab,
    " as usual.
    let g:fzf_action = { 'enter': 'tabnew' }
endfunc

Troubleshooting by log

Enable print c-tyle log

    Plug 'huawenyu/vimlogger'

    " Also append this line to your ~/.vimrc to start our logfile
    silent! call logger#init('ALL', ['/tmp/vim.log'])

Check runtime log

• Start vim
• Using another terminal, off couse it's easy if you using tmux which you'll not regret to meet the tools. watching the log by tail -f /tmp/vim.log

License

Vim license, see LICENSE