There is a small chance that a user sends SIGINT (or any other signal
that is trapped) when we're already in clean_up() which used to lead to
trap_exit() being executed and the remaining code in clean_up() being
skipped due to the bash signal/trap handler blocking EXIT (since its
handler is already being executed, even if it's interrupted).
In practice, this behaviour caused unexpected results (primarily because
pressing ^C at the wrong time left a lock file behind):
$ ./repo-add extra.db.tar.gz foobar
==> Extracting database to a temporary location...
^C
==> ERROR: Aborted by user! Exiting...
$ ./repo-add extra.db.tar.gz foobar
==> Extracting database to a temporary location...
==> ERROR: File 'foobar' not found.
==> No packages modified, nothing to do.
^C
==> ERROR: Aborted by user! Exiting...
$ ./repo-add extra.db.tar.gz foobar
==> ERROR: Failed to acquire lockfile: extra.db.tar.gz.lck.
==> ERROR: Held by process 18522
Fix this and reduce the chance of race conditions in signal handlers by:
* Unhooking all traps in both clean_up() and trap_exit().
* Call clean_up() explicitly in trap_exit() to make sure we remove the
lock file and the temporary directory even if we send SIGINT when
clean_up() is already being executed but didn't reach the unhook code
yet.
Also, add an optional parameter to clean_up() to allow for setting an
explicit exit code when we call clean_up() from trap_exit().
Signed-off-by: Lukas Fleischer <[email protected]>
---
scripts/repo-add.sh.in | 10 ++++++++--
1 files changed, 8 insertions(+), 2 deletions(-)
diff --git a/scripts/repo-add.sh.in b/scripts/repo-add.sh.in
index 29b150c..d147b87 100644
--- a/scripts/repo-add.sh.in
+++ b/scripts/repo-add.sh.in
@@ -520,13 +520,19 @@ remove() {
}
trap_exit() {
+ # unhook all traps to avoid race conditions
+ trap '' EXIT TERM HUP QUIT INT ERR
+
echo
error "$@"
- exit 1
+ clean_up 1
}
clean_up() {
- local exit_code=$?
+ local exit_code=${1:-$?}
+
+ # unhook all traps to avoid race conditions
+ trap '' EXIT TERM HUP QUIT INT ERR
[[ -d $tmpdir ]] && rm -rf "$tmpdir"
(( CLEAN_LOCK )) && [[ -f $LOCKFILE ]] && rm -f "$LOCKFILE"
--
1.7.7
