.sh

commit 1cf8cea074471577f784756fb1ca1f5ce9449432
parent 4fa5ed4c2dd8cd9c47add37725d99c74732867bc
Author: Byron Torres <b@torresjrjr.com>
Date:   Fri,  7 Apr 2023 17:13:12 +0100

gfa*: revamp, output new lines lazily

Diffstat:
M
bin/gfa
 | 
74
+++++++++++++++++++++++++++++++++++++++++++++++++++++++-------------------

1 file changed, 55 insertions(+), 19 deletions(-)
diff --git a/bin/gfa b/bin/gfa
@@ -1,15 +1,26 @@
-#!/bin/sh -u
+#!/bin/sh -eu
 # gfa -- fetch all git repos in cwd
 
 println() {
-	local line=$(( $1 + 1 )) column=$2 colour=$3 text=$4
-	env printf '\r\e[%sB\e[%sC\e[%sm%s\e[m\r\e[%sA\e[%sC' \
-		$line $column $colour "$text" $line $column
+	{ flock 3
+		line=$1 column=$2 colour=$3 text=$4
+		lines=$( wc -l </tmp/gfa-lines )
+		offset=$(( $lines - $line + 1))
+		env printf '\r\e[%sA\e[%sC\e[%sm%s\e[m\r\e[%sB\r' \
+			$offset $column \
+			$colour "$text" \
+			$offset
+	} 3</tmp/gfa-mutex
 }
 
 worker() {
-	local n=$1
-	local dir="${2%/.git}"
+	local n="$( head -n1 /tmp/gfa-inits )"
+	local dir="${1%/.git}"
+
+	{ flock 3
+		env printf '\n' | tee -a /tmp/gfa-lines
+	} 3</tmp/gfa-mutex
+
 	cd "$cwd"
 	cd "$dir"
 	println $n 0 0  "${dir#./}"
@@ -28,15 +39,19 @@ worker() {
 
 	case "$commits" in
 		-1)
-			println $n $width 31 '?'
+			println "$n" $width 31  '?'
 			;;
 		0)
-			println $n $width 0  '.'
+			println "$n" $width 0  '.'
 			;;
 		*)
-			println $n $width 32  "($commits)"
+			println "$n" $width 32  "($commits)"
 			;;
 	esac
+
+	env printf '\n' >/tmp/gfa-done
+	env printf '\n' >/tmp/gfa-finis
+	return
 }
 
 
@@ -45,19 +60,40 @@ repos=$( find -maxdepth 3 -path '*/.git' -not -path '*/_*' | sort )
 
 [ "$repos" ] || printf >&2 'No git repos here\n'
 
-width="$(echo "$repos" | wc -L)"
-total="$(echo "$repos" | wc -l)"
+width="$(printf '%s\n' "$repos" | wc -L)"
+total="$(printf '%s\n' "$repos" | wc -l)"
+
+touch /tmp/gfa-dummy
+rm /tmp/gfa-*
+touch /tmp/gfa-lines
+touch /tmp/gfa-mutex
+mkfifo /tmp/gfa-inits /tmp/gfa-finis /tmp/gfa-done
 
-env printf '%s\r ~ \n' $(seq $(( total + 1 )))
-env printf '\e[%sA' $(( total + 1 ))
-env printf '[fetching repos]\r'
+winsz=32
+lines=0
+
+env printf '[fetching %s repos]\n' "$total"
 
-wg='' n=0
 for dir in $repos
 do
-	worker $n "$dir" &  wg="$wg $! " n=$(( n + 1 ))
-	sleep 0.05
+	( worker "$dir" )&
 done
 
-wait $wg
-env printf '\r\e[%sB' $(( total + 1 ))
+worker_manager() {
+	for N in $(seq $total)
+	do
+		[ "$N" -gt $winsz ] && {
+			head -n1 /tmp/gfa-finis >/dev/null
+		}
+
+		env printf '%s\n' "$N"
+		sleep 0.1
+	done
+}
+
+worker_manager >/tmp/gfa-inits &
+
+for N in $(seq $total)
+do
+	head -n1 /tmp/gfa-done >/dev/null
+done