There are 3 things of note here:
- Pass extra arguments to stat_busy, to allow it to take printf-type
messages.
- Check to make sure that process doesn't already own the lock. The code
for this is mostly taken from mkarchroot; the logic had been dropped
when the functions were pulled into common.sh
- The old mkarchroot code used `readlink -f` on the file in /dev/fd to
resolve symlinks. This didn't work correctly if there is a symlink
in the path of the lock file. One solution would have been to use
`readlink -f` on both files, but it is simpler to use `[[ a -ef b ]]`.
---
lib/common.sh | 38 ++++++++++++++++++++++++++++----------
1 file changed, 28 insertions(+), 10 deletions(-)
diff --git a/lib/common.sh b/lib/common.sh
index d6da1ab..9cc4e1d 100644
--- a/lib/common.sh
+++ b/lib/common.sh
@@ -134,25 +134,43 @@ get_full_version() {
}
##
-# usage : lock( $fd, $file, $message )
+# usage : lock( $fd, $file, $message, [ $message_arguments... ] )
##
lock() {
- eval "exec $1>"'"$2"'
- if ! flock -n $1; then
- stat_busy "$3"
- flock $1
+ local fd=$1
+ local file=$2
+ local mesg=("${@:3}")
+
+ # Only reopen the FD if it wasn't handed to us
+ if ! [[ "/dev/fd/$fd" -ef "$file" ]]; then
+ mkdir -p "${file%/*}"
+ eval "exec $fd>"'"$file"'
+ fi
+
+ if ! flock -n $fd; then
+ stat_busy "${mesg[@]}"
+ flock $fd
stat_done
fi
}
##
-# usage : slock( $fd, $file, $message )
+# usage : slock( $fd, $file, $message, [ $message_arguments... ] )
##
slock() {
- eval "exec $1>"'"$2"'
- if ! flock -sn $1; then
- stat_busy "$3"
- flock -s $1
+ local fd=$1
+ local file=$2
+ local mesg=("${@:3}")
+
+ # Only reopen the FD if it wasn't handed to us
+ if ! [[ "/dev/fd/$fd" -ef "$file" ]]; then
+ mkdir -p "${file%/*}"
+ eval "exec $fd>"'"$file"'
+ fi
+
+ if ! flock -sn $fd; then
+ stat_busy "${mesg[@]}"
+ flock -s $fd
stat_done
fi
}
--
1.9.2
