diff options
Diffstat (limited to 'lib/async_prompt.zsh')
| -rw-r--r-- | lib/async_prompt.zsh | 145 |
1 files changed, 145 insertions, 0 deletions
diff --git a/lib/async_prompt.zsh b/lib/async_prompt.zsh new file mode 100644 index 000000000..151e24b8c --- /dev/null +++ b/lib/async_prompt.zsh @@ -0,0 +1,145 @@ +# The async code is taken from +# https://github.com/zsh-users/zsh-autosuggestions/blob/master/src/async.zsh +# https://github.com/woefe/git-prompt.zsh/blob/master/git-prompt.zsh + +zmodload zsh/system +autoload -Uz is-at-least + +# For now, async prompt function handlers are set up like so: +# First, define the async function handler and register the handler +# with _omz_register_handler: +# +# function _git_prompt_status_async { +# # Do some expensive operation that outputs to stdout +# } +# _omz_register_handler _git_prompt_status_async +# +# Then add a stub prompt function in `$PROMPT` or similar prompt variables, +# which will show the output of "$_OMZ_ASYNC_OUTPUT[handler_name]": +# +# function git_prompt_status { +# echo -n $_OMZ_ASYNC_OUTPUT[_git_prompt_status_async] +# } +# +# RPROMPT='$(git_prompt_status)' +# +# This API is subject to change and optimization. Rely on it at your own risk. + +function _omz_register_handler { + setopt localoptions noksharrays unset + typeset -ga _omz_async_functions + # we want to do nothing if there's no $1 function or we already set it up + if [[ -z "$1" ]] || (( ! ${+functions[$1]} )) \ + || (( ${_omz_async_functions[(Ie)$1]} )); then + return + fi + _omz_async_functions+=("$1") + # let's add the hook to async_request if it's not there yet + if (( ! ${precmd_functions[(Ie)_omz_async_request]} )) \ + && (( ${+functions[_omz_async_request]})); then + autoload -Uz add-zsh-hook + add-zsh-hook precmd _omz_async_request + fi +} + +# Set up async handlers and callbacks +function _omz_async_request { + setopt localoptions noksharrays unset + local -i ret=$? + typeset -gA _OMZ_ASYNC_FDS _OMZ_ASYNC_PIDS _OMZ_ASYNC_OUTPUT + + # executor runs a subshell for all async requests based on key + local handler + for handler in ${_omz_async_functions}; do + (( ${+functions[$handler]} )) || continue + + local fd=${_OMZ_ASYNC_FDS[$handler]:--1} + local pid=${_OMZ_ASYNC_PIDS[$handler]:--1} + + # If we've got a pending request, cancel it + if (( fd != -1 && pid != -1 )) && { true <&$fd } 2>/dev/null; then + # Close the file descriptor and remove the handler + exec {fd}<&- + zle -F $fd + + # Zsh will make a new process group for the child process only if job + # control is enabled (MONITOR option) + if [[ -o MONITOR ]]; then + # Send the signal to the process group to kill any processes that may + # have been forked by the async function handler + kill -TERM -$pid 2>/dev/null + else + # Kill just the child process since it wasn't placed in a new process + # group. If the async function handler forked any child processes they may + # be orphaned and left behind. + kill -TERM $pid 2>/dev/null + fi + fi + + # Define global variables to store the file descriptor, PID and output + _OMZ_ASYNC_FDS[$handler]=-1 + _OMZ_ASYNC_PIDS[$handler]=-1 + + # Fork a process to fetch the git status and open a pipe to read from it + exec {fd}< <( + # Tell parent process our PID + builtin echo ${sysparams[pid]} + # Set exit code for the handler if used + () { return $ret } + # Run the async function handler + $handler + ) + + # Save FD for handler + _OMZ_ASYNC_FDS[$handler]=$fd + + # There's a weird bug here where ^C stops working unless we force a fork + # See https://github.com/zsh-users/zsh-autosuggestions/issues/364 + # and https://github.com/zsh-users/zsh-autosuggestions/pull/612 + is-at-least 5.8 || command true + + # Save the PID from the handler child process + read -u $fd "_OMZ_ASYNC_PIDS[$handler]" + + # When the fd is readable, call the response handler + zle -F "$fd" _omz_async_callback + done +} + +# Called when new data is ready to be read from the pipe +function _omz_async_callback() { + emulate -L zsh + + local fd=$1 # First arg will be fd ready for reading + local err=$2 # Second arg will be passed in case of error + + if [[ -z "$err" || "$err" == "hup" ]]; then + # Get handler name from fd + local handler="${(k)_OMZ_ASYNC_FDS[(r)$fd]}" + + # Store old output which is supposed to be already printed + local old_output="${_OMZ_ASYNC_OUTPUT[$handler]}" + + # Read output from fd + IFS= read -r -u $fd -d '' "_OMZ_ASYNC_OUTPUT[$handler]" + + # Repaint prompt if output has changed + if [[ "$old_output" != "${_OMZ_ASYNC_OUTPUT[$handler]}" ]]; then + zle .reset-prompt + zle -R + fi + + # Close the fd + exec {fd}<&- + fi + + # Always remove the handler + zle -F "$fd" + + # Unset global FD variable to prevent closing user created FDs in the precmd hook + _OMZ_ASYNC_FDS[$handler]=-1 + _OMZ_ASYNC_PIDS[$handler]=-1 +} + +autoload -Uz add-zsh-hook +add-zsh-hook precmd _omz_async_request |