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zsh/theme/gitstatus/README.md
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zsh/theme/gitstatus/README.md
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# gitstatus
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**gitstatus** is a 10x faster alternative to `git status` and `git describe`. Its primary use
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case is to enable fast git prompt in interactive shells.
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Heavy lifting is done by **gitstatusd** -- a custom binary written in C++. It comes with Zsh and
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Bash bindings for integration with shell.
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## Table of Contents
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1. [Using from Zsh](#using-from-zsh)
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1. [Using from Bash](#using-from-bash)
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2. [Using from other shells](#using-from-other-shells)
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1. [How it works](#how-it-works)
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1. [Benchmarks](#benchmarks)
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1. [Why fast](#why-fast)
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1. [Requirements](#requirements)
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1. [Compiling](#compiling)
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1. [License](#license)
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## Using from Zsh
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The easiest way to take advantage of gitstatus from Zsh is to use a theme that's already integrated
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with it. For example, [Powerlevel10k](https://github.com/romkatv/powerlevel10k) is a flexible and
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fast theme with first-class gitstatus integration. If you install Powerlevel10k, you don't need to
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install gitstatus.
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For those who wish to use gitstatus without a theme, there is
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[gitstatus.prompt.zsh](gitstatus.prompt.zsh). Install it as follows:
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```zsh
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git clone --depth=1 https://github.com/romkatv/gitstatus.git ~/gitstatus
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echo 'source ~/gitstatus/gitstatus.prompt.zsh' >>! ~/.zshrc
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```
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Users in China can use the official mirror on gitee.com for faster download.<br>
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中国大陆用户可以使用 gitee.com 上的官方镜像加速下载.
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```zsh
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git clone --depth=1 https://gitee.com/romkatv/gitstatus.git ~/gitstatus
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echo 'source ~/gitstatus/gitstatus.prompt.zsh' >>! ~/.zshrc
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```
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Alternatively, if you have Homebrew installed:
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```zsh
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brew install romkatv/gitstatus/gitstatus
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echo "source $(brew --prefix)/opt/gitstatus/gitstatus.prompt.zsh" >>! ~/.zshrc
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```
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(If you choose this option, replace `~/gitstatus` with `$(brew --prefix)/opt/gitstatus/gitstatus`
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in all code snippets below.)
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_Make sure to disable your current theme if you have one._
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This will give you a basic yet functional prompt with git status in it. It's
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[over 10x faster](#benchmarks) than any alternative that can give you comparable prompt. In order
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to customize it, set `PROMPT` and/or `RPROMPT` at the end of `~/.zshrc` after sourcing
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`gitstatus.prompt.zsh`. Insert `${GITSTATUS_PROMPT}` where you want git status to go. For example:
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```zsh
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source ~/gitstatus/gitstatus.prompt.zsh
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PROMPT='%~%# ' # left prompt: directory followed by %/# (normal/root)
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RPROMPT='$GITSTATUS_PROMPT' # right prompt: git status
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```
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The expansion of `${GITSTATUS_PROMPT}` can contain the following bits:
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| segment | meaning |
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|-------------|-------------------------------------------------------|
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| `master` | current branch |
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| `#v1` | HEAD is tagged with `v1`; not shown when on a branch |
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| `@5fc6fca4` | current commit; not shown when on a branch or tag |
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| `⇣1` | local branch is behind the remote by 1 commit |
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| `⇡2` | local branch is ahead of the remote by 2 commits |
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| `⇠3` | local branch is behind the push remote by 3 commits |
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| `⇢4` | local branch is ahead of the push remote by 4 commits |
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| `*5` | there are 5 stashes |
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| `merge` | merge is in progress (could be some other action) |
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| `~6` | there are 6 merge conflicts |
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| `+7` | there are 7 staged changes |
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| `!8` | there are 8 unstaged changes |
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| `?9` | there are 9 untracked files |
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`$GITSTATUS_PROMPT_LEN` tells you how long `$GITSTATUS_PROMPT` is when printed to the console.
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[gitstatus.prompt.zsh](gitstatus.prompt.zsh) has an example of using it to truncate the current
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directory.
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If you'd like to change the format of git status, or want to have greater control over the
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process of assembling `PROMPT`, you can copy and modify parts of
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[gitstatus.prompt.zsh](gitstatus.prompt.zsh) instead of sourcing the script. Your `~/.zshrc`
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might look something like this:
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```zsh
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source ~/gitstatus/gitstatus.plugin.zsh
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function my_set_prompt() {
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PROMPT='%~%# '
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RPROMPT=''
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if gitstatus_query MY && [[ $VCS_STATUS_RESULT == ok-sync ]]; then
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RPROMPT=${${VCS_STATUS_LOCAL_BRANCH:-@${VCS_STATUS_COMMIT}}//\%/%%} # escape %
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(( VCS_STATUS_NUM_STAGED )) && RPROMPT+='+'
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(( VCS_STATUS_NUM_UNSTAGED )) && RPROMPT+='!'
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(( VCS_STATUS_NUM_UNTRACKED )) && RPROMPT+='?'
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fi
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setopt no_prompt_{bang,subst} prompt_percent # enable/disable correct prompt expansions
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}
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gitstatus_stop 'MY' && gitstatus_start -s -1 -u -1 -c -1 -d -1 'MY'
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autoload -Uz add-zsh-hook
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add-zsh-hook precmd my_set_prompt
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```
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This snippet is sourcing `gitstatus.plugin.zsh` rather than `gitstatus.prompt.zsh`. The former
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defines low-level bindings that communicate with gitstatusd over pipes. The latter is a simple
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script that uses these bindings to assemble git prompt.
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Unlike [Powerlevel10k](https://github.com/romkatv/powerlevel10k), code based on
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[gitstatus.prompt.zsh](gitstatus.prompt.zsh) is communicating with gitstatusd synchronously. This
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can make your prompt slow when working in a large git repository or on a slow machine. To avoid
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this problem, call `gitstatus_query` asynchronously as documented in
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[gitstatus.plugin.zsh](gitstatus.plugin.zsh). This can be quite challenging.
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## Using from Bash
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The easiest way to take advantage of gitstatus from Bash is via
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[gitstatus.prompt.sh](gitstatus.prompt.sh). Install it as follows:
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```bash
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git clone --depth=1 https://github.com/romkatv/gitstatus.git ~/gitstatus
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echo 'source ~/gitstatus/gitstatus.prompt.sh' >> ~/.bashrc
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```
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Users in China can use the official mirror on gitee.com for faster download.<br>
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中国大陆用户可以使用 gitee.com 上的官方镜像加速下载.
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```bash
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git clone --depth=1 https://gitee.com/romkatv/gitstatus.git ~/gitstatus
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echo 'source ~/gitstatus/gitstatus.prompt.sh' >> ~/.bashrc
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```
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Alternatively, if you have Homebrew installed:
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```zsh
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brew install romkatv/gitstatus/gitstatus
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echo "source $(brew --prefix)/opt/gitstatus/gitstatus.prompt.sh" >> ~/.bashrc
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```
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(If you choose this option, replace `~/gitstatus` with `$(brew --prefix)/opt/gitstatus/gitstatus`
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in all code snippets below.)
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This will give you a basic yet functional prompt with git status in it. It's
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[over 10x faster](#benchmarks) than any alternative that can give you comparable prompt.
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In order to customize your prompt, set `PS1` at the end of `~/.bashrc` after sourcing
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`gitstatus.prompt.sh`. Insert `${GITSTATUS_PROMPT}` where you want git status to go. For example:
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```bash
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source ~/gitstatus/gitstatus.prompt.sh
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PS1='\w ${GITSTATUS_PROMPT}\n\$ ' # directory followed by git status and $/# (normal/root)
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```
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The expansion of `${GITSTATUS_PROMPT}` can contain the following bits:
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| segment | meaning |
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|-------------|-------------------------------------------------------|
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| `master` | current branch |
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| `#v1` | HEAD is tagged with `v1`; not shown when on a branch |
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| `@5fc6fca4` | current commit; not shown when on a branch or tag |
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| `⇣1` | local branch is behind the remote by 1 commit |
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| `⇡2` | local branch is ahead of the remote by 2 commits |
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| `⇠3` | local branch is behind the push remote by 3 commits |
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| `⇢4` | local branch is ahead of the push remote by 4 commits |
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| `*5` | there are 5 stashes |
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| `merge` | merge is in progress (could be some other action) |
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| `~6` | there are 6 merge conflicts |
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| `+7` | there are 7 staged changes |
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| `!8` | there are 8 unstaged changes |
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| `?9` | there are 9 untracked files |
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If you'd like to change the format of git status, or want to have greater control over the
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process of assembling `PS1`, you can copy and modify parts of
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[gitstatus.prompt.sh](gitstatus.prompt.sh) instead of sourcing the script. Your `~/.bashrc` might
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look something like this:
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```bash
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source ~/gitstatus/gitstatus.plugin.sh
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function my_set_prompt() {
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PS1='\w'
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if gitstatus_query && [[ "$VCS_STATUS_RESULT" == ok-sync ]]; then
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if [[ -n "$VCS_STATUS_LOCAL_BRANCH" ]]; then
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PS1+=" ${VCS_STATUS_LOCAL_BRANCH//\\/\\\\}" # escape backslash
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else
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PS1+=" @${VCS_STATUS_COMMIT//\\/\\\\}" # escape backslash
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fi
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(( VCS_STATUS_HAS_STAGED" )) && PS1+='+'
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(( VCS_STATUS_HAS_UNSTAGED" )) && PS1+='!'
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(( VCS_STATUS_HAS_UNTRACKED" )) && PS1+='?'
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fi
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PS1+='\n\$ '
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shopt -u promptvars # disable expansion of '$(...)' and the like
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}
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gitstatus_stop && gitstatus_start
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PROMPT_COMMAND=my_set_prompt
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```
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This snippet is sourcing `gitstatus.plugin.sh` rather than `gitstatus.prompt.sh`. The former
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defines low-level bindings that communicate with gitstatusd over pipes. The latter is a simple
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script that uses these bindings to assemble git prompt.
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Note: Bash bindings, unlike Zsh bindings, don't support asynchronous calls.
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## Using from other shells
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If there are no gitstatusd bindings for your shell, you'll need to get your hands dirty.
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Use the existing bindings for inspiration; run `gitstatusd --help` or read the same thing in
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[options.cc](src/options.cc).
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## How it works
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gitstatusd reads requests from stdin and prints responses to stdout. Requests contain an ID and
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a directory. Responses contain the same ID and machine-readable git status for the directory.
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gitstatusd keeps some state in memory for the directories it has seen in order to serve future
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requests faster.
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[Zsh bindings](gitstatus.plugin.zsh) and [Bash bindings](gitstatus.plugin.sh) start gitstatusd in
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the background and communicate with it via pipes. Themes such as
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[Powerlevel10k](https://github.com/romkatv/powerlevel10k) use these bindings to put git status in
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`PROMPT`.
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Note that gitstatus cannot be used as a drop-in replacement for `git status` command as it doesn't
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produce output in the same format. It does perform the same computation though.
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## Benchmarks
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The following benchmark results were obtained on Intel i9-7900X running Ubuntu 18.04 in
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a clean [chromium](https://github.com/chromium/chromium) repository synced to `9394e49a`. The
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repository was checked out to an ext4 filesystem on M.2 SSD.
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Three functionally equivalent tools for computing git status were benchmarked:
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* `gitstatusd`
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* `git` with `core.untrackedcache` enabled and `core.fsmonitor` disabled
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* `lg2` -- a demo/example executable from [libgit2](https://github.com/romkatv/libgit2) that
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implements a subset of `git` functionality on top of libgit2 API; for the purposes of this
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benchmark the subset is sufficient to generate the same data as the other tools
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Every tool was benchmark in cold and hot conditions. For `git` the first run in a repository was
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considered cold, with the following runs considered hot. `lg2` was patched to compute results twice
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in a single invocation without freeing the repository in between; the second run was considered hot.
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The same patching was not done for `git` because `git` cannot be easily modified to refresh inmemory
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index state between invocations; in fact, this limitation is one of the primary reasons developers
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use libgit2. `gitstatusd` was benchmarked similarly to `lg2` with two result computations in the
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same invocation.
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Two commands were benchmarked: `status` and `describe`.
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### Status
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In this benchmark all tools were computing the equivalent of `git status`. Lower numbers are better.
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| Tool | Cold | Hot |
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|---------------|-----------:|------------:|
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| **gitstatus** | **291 ms** | **30.9 ms** |
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| git | 876 ms | 295 ms |
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| lg2 | 1730 ms | 1310 ms |
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gitstatusd is substantially faster than the alternatives, especially on hot runs. Note that hot runs
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are of primary importance to the main use case of gitstatus in interactive shells.
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The performance of `git status` fluctuated wildly in this benchmarks for reasons unknown to the
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author. Moreover, performance is sticky -- once `git status` settles around a number, it stays
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there for a long time. Numbers as diverse as 295, 352, 663 and 730 had been observed on hot runs on
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the same repository. The number in the table is the lowest (fastest or best) that `git status` had
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shown.
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### Describe
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In this benchmark all tools were computing the equivalent of `git describe --tags --exact-match`
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to find tags that resolve to the same commit as `HEAD`. Lower numbers are better.
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| Tool | Cold | Hot |
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|---------------|------------:|--------------:|
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| **gitstatus** | **4.04 ms** | **0.0345 ms** |
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| git | 18.0 ms | 14.5 ms |
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| lg2 | 185 ms | 45.2 ms |
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gitstatusd is once again faster than the alternatives, more so on hot runs.
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## Why fast
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Since gitstatusd doesn't have to print all staged/unstaged/untracked files but only report
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whether there are any, it can terminate repository scan early. It can also remember which files
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were dirty on the previous run and check them first on the next run to avoid the scan entirely if
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the files are still dirty. However, the benchmarks above were performed in a clean repository where
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these shortcuts do not trigger. All benchmarked tools had to do the same work -- check the status
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of every file in the index to see if it has changed, check every directory for newly created files,
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etc. And yet, gitstatusd came ahead by a large margin. This section describes what it does that
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makes it so fast.
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Most of the following comparisons are done against libgit2 rather than git because of the author's
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familiarity with the former but not the with latter. libgit2 has clean, well-documented APIs and an
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elegant implementation, which makes it so much easier to work with and to analyze performance
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bottlenecks.
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### Summary for the impatient
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Under the benchmark conditions described above, the equivalent of libgit2's
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`git_diff_index_to_workdir` (the most expensive part of `status` command) is 46.3 times faster in
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gitstatusd. The speedup comes from the following sources.
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* gitstatusd uses more efficient data structures and algorithms and employs performance-conscious
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coding style throughout the codebase. This reduces CPU time in userspace by 32x compared to libgit2.
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* gitstatusd uses less expensive system calls and makes fewer of them. This reduces CPU time spent
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in kernel by 1.9x.
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* gitstatusd can utilize multiple cores to scan index and workdir in parallel with almost perfect
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scaling. This reduces total run time by 12.4x while having virtually no effect on total CPU time.
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### Problem statement
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The most resource-intensive part of the `status` command is finding the difference between _index_
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and _workdir_ (`git_diff_index_to_workdir` in libgit2). Index is a list of all files in the git
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repository with their last modification times. This is an obvious simplification but it suffices for
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this exposition. On disk, index is stored sorted by file path. Here's an example of git index:
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| File | Last modification time |
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|-------------|-----------------------:|
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| Makefile | 2019-04-01T14:12:32Z |
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| src/hello.c | 2019-04-01T14:12:00Z |
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| src/hello.h | 2019-04-01T14:12:32Z |
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This list needs to be compared to the list of files in the working directory. If any of the files
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listed in the index are missing from the workdir or have different last modification time, they are
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"unstaged" in gitstatusd parlance. If you run `git status`, they'll be shown as "changes not staged
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for commit". Thus, any implementation of `status` command has to call `stat()` or one of its
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variants on every file in the index.
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In addition, all files in the working directory for which there is no entry in the index at all are
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"untracked". `git status` will show them as "untracked files". Finding untracked files requires some
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form of work directory traversal.
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### Single-threaded scan
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Let's see how `git_diff_index_to_workdir` from libgit2 accomplishes these tasks. Here's its CPU
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profile from 200 hot runs over chromium repository.
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(The CPU profile was created with [gperftools](https://github.com/gperftools/gperftools) and
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rendered with [pprof](https://github.com/google/pprof)).
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We can see `__GI__lxstat` taking a lot of time. This is the `stat()` call for every file in the
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index. We can also identify `__opendir`, `__readdir` and `__GI___close_nocancel` -- glibc wrappers
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for reading the contents of a directory. This is for finding untracked files. Out of the total 232
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seconds, 111 seconds -- or 47.7% -- was spent on these calls. The rest is computation -- comparing
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strings, sorting arrays, etc.
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Now let's take a look at the CPU profile of gitstatusd on the same task.
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The first impression is that this profile looks pruned. This isn't an artifact. The profile was
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generated with the same tools and the same flags as the profile of libgit2.
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Since both profiles were generated from the same workload, absolute numbers can be compared. We can
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see that gitstatusd took 62 seconds in total compared to libgit2's 232 seconds. System calls at the
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core of the algorithm are clearly visible. `__GI___fxstatat` is a flavor of `stat()`, and the other
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three calls -- `__libc_openat64`, `__libc_close` and `__GI___fxstat` are responsible for opening
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directories and finding untracked files. Notice that there is almost nothing else in the profile
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apart from these calls. The rest of the code accounts for 3.77 seconds of CPU time -- 32 times less
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than in libgit2.
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So, one reason gitstatusd is fast is that it has efficient diffing code -- very little time is spent
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outside of kernel. However, if we look closely, we can notice that system calls in gitstatusd are
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_also_ faster than in libgit2. For example, libgit2 spent 72.07 seconds in `__GI__lxstat` while
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gitstatusd spent only 48.82 seconds in `__GI___fxstatat`. There are two reasons for this difference.
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First, libgit2 makes more `stat()` calls than is strictly required. It's not necessary to stat
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directories because index only has files. There are 25k directories in chromium repository (and 300k
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files) -- that's 25k `stat()` calls that could be avoided. The second reason is that libgit2 and
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gitstatusd use different flavors of `stat()`. libgit2 uses `lstat()`, which takes a path to the file
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as input. Its performance is linear in the number of subdirectories in the path because it needs to
|
||||
perform a lookup for every one of them and to check permissions. gitstatusd uses `fstatat()`, which
|
||||
takes a file descriptor to the parent directory and a name of the file. Just a single lookup, less
|
||||
CPU time.
|
||||
|
||||
Similarly to `lstat()` vs `fstatat()`, it's faster to open files and directories with `openat()`
|
||||
from the parent directory file descriptor than with regular `open()` that accepts full file path.
|
||||
gitstatusd takes advantage of `openat()` to open directories as fast as possible. It opens about 90%
|
||||
of the directories (this depends on the actual directory structure of the repository) from the
|
||||
immediate parent -- the most efficient way -- and the remaining 10% it opens from the repository's
|
||||
root directory. The reason it's done this way is to keep the maximum number of simultaneously open
|
||||
file descriptors bounded. libgit2 can have O(repository depth) simultaneously open file descriptors,
|
||||
which may be OK for a single-threaded application but can balloon to a large number when scans are
|
||||
done by many threads simultaneously, like in gitstatusd.
|
||||
|
||||
There is no equivalent to `__opendir` or `__readdir` in the gitstatusd profile because it uses the
|
||||
equivalent of [untracked cache](https://git-scm.com/docs/git-update-index#_untracked_cache) from
|
||||
git. On the first scan of the workdir gitstatusd lists all files just like libgit2. But, unlike
|
||||
libgit2, it remembers the last modification time of every directory along with the list of
|
||||
untracked files under it. On the next scan, gitstatusd can skip listing files in directories whose
|
||||
last modification time hasn't changed.
|
||||
|
||||
To summarize, here's what gitstatusd was doing when the CPU profile was captured:
|
||||
|
||||
1. `__libc_openat64`: Open every directory for which there are files in the index.
|
||||
2. `__GI___fxstat`: Check last modification time of the directory. Since it's the same as on the
|
||||
last scan, this directory has the same list of untracked files as before, which is empty (the
|
||||
repository is clean).
|
||||
3. `__GI___fxstatat`: Check last modification time for every file in the index that belongs to this
|
||||
directory.
|
||||
4. `__libc_close`: Close the file descriptor to the directory.
|
||||
|
||||
Here's how the very first scan of a repository looks like in gitstatusd:
|
||||
|
||||

|
||||
|
||||
(Some glibc functions are mislabel on this profile. `explicit_bzero` and `__nss_passwd_lookup` are
|
||||
in reality `strcmp` and `memcmp`.)
|
||||
|
||||
This is a superset of the previous -- hot -- profile, with an extra `syscall` and string sorting for
|
||||
directory listing. gitstatusd uses `getdents64` Linux system call directly, bypassing the glibc
|
||||
wrapper that libgit2 uses. This is 23% faster. The details of this optimization can be found in a
|
||||
[separate document](docs/listdir.md).
|
||||
|
||||
### Multithreading
|
||||
|
||||
The diffing algorithm in gitstatusd was designed from the ground up with the intention of using it
|
||||
concurrently from multiple threads. With a fast SSD, `status` is CPU bound, so taking advantage of
|
||||
all available CPU cores is an obvious way to yield results faster.
|
||||
|
||||
gitstatusd exhibits almost perfect scaling from multithreading. Engaging all cores allows it to
|
||||
produce results 12.4 times faster than in single-threaded execution. This is on Intel i9-7900X with
|
||||
10 cores (20 with hyperthreading) with single-core frequency of 4.3GHz and all-core frequency of
|
||||
4.0GHz.
|
||||
|
||||
Note: `git status` also uses all available cores in some parts of its algorithm while `lg2` does
|
||||
everything in a single thread.
|
||||
|
||||
### Postprocessing
|
||||
|
||||
Once the difference between the index and the workdir is found, we have a list of _candidates_ --
|
||||
files that may be unstaged or untracked. To make the final judgement, these files need to be checked
|
||||
against `.gitignore` rules and a few other things.
|
||||
|
||||
gitstatusd uses [patched libgit2](https://github.com/romkatv/libgit2) for this step. This fork
|
||||
adds several optimizations that make libgit2 faster. The patched libgit2 performs more than twice
|
||||
as fast in the benchmark as the original even without changes in the user code (that is, in the
|
||||
code that uses the libgit2 APIs). The fork also adds several API extensions, most notable of which
|
||||
is the support for multi-threaded scans. If `lg2 status` is modified to take advantage of these
|
||||
extensions, it outperforms the original libgit2 by a factor of 18. Lastly, the fork fixes a score of
|
||||
bugs, most of which become apparent only when using libgit2 from multiple threads.
|
||||
|
||||
_WARNING: Changes to libgit2 are extensive but the testing they underwent isn't. It is
|
||||
**not recommended** to use the patched libgit2 in production._
|
||||
|
||||
## Requirements
|
||||
|
||||
* To compile: binutils, cmake, gcc, g++, git and GNU make.
|
||||
* To run: Linux, macOS, FreeBSD, Android, WSL, Cygwin or MSYS2.
|
||||
|
||||
## Compiling
|
||||
|
||||
There are prebuilt `gitstatusd` binaries in [releases](
|
||||
https://github.com/romkatv/gitstatus/releases). When using the official shell bindings
|
||||
provided by gitstatus, the right binary for your architecture gets downloaded automatically.
|
||||
|
||||
If prebuilt binaries don't work for you, you'll need to get your hands dirty.
|
||||
|
||||
### Compiling for personal use
|
||||
|
||||
```zsh
|
||||
git clone --depth=1 https://github.com/romkatv/gitstatus.git
|
||||
cd gitstatus
|
||||
./build -w -s -d docker
|
||||
```
|
||||
|
||||
Users in China can use the official mirror on gitee.com for faster download.<br>
|
||||
中国大陆用户可以使用 gitee.com 上的官方镜像加速下载.
|
||||
|
||||
```zsh
|
||||
git clone --depth=1 https://gitee.com/romkatv/gitstatus.git
|
||||
cd gitstatus
|
||||
./build -w -s -d docker
|
||||
```
|
||||
|
||||
- If it says that `-d docker` is not supported on your OS, remove this flag.
|
||||
- If it says that `-s` is not supported on your OS, remove this flag.
|
||||
- If it tell you to install docker but you cannot or don't want to, remove `-d docker`.
|
||||
- If it says that some command is missing, install it.
|
||||
|
||||
If everything goes well, the newly built binary will appear in `./usrbin`. It'll be picked up
|
||||
by shell bindings automatically.
|
||||
|
||||
When you update shell bindings, they may refuse to work with the binary you've built earlier. In
|
||||
this case you'll need to rebuild.
|
||||
|
||||
If you are using gitstatus through [Powerlevel10k](https://github.com/romkatv/powerlevel10k), the
|
||||
instructions are the same except that you don't need to clone gitstatus. Instead, change your
|
||||
current directory to `/path/to/powerlevel10k/gitstatus` (`/path/to/powerlevel10k` is the directory
|
||||
where you've installed Powerlevel10k) and run `./build -w -s -d docker` from there as described
|
||||
above.
|
||||
|
||||
### Compiling for distribution
|
||||
|
||||
It's currently neither easy nor recommended to package and distribute gitstatus. There are no
|
||||
instructions you can follow that would allow you to easily update your package when new versions of
|
||||
gitstatus are released. This may change in the future but not soon.
|
||||
|
||||
## License
|
||||
|
||||
GNU General Public License v3.0. See [LICENSE](LICENSE). Contributions are covered by the same
|
||||
license.
|
Loading…
Add table
Add a link
Reference in a new issue