diff options
| author | Ron Yorston <rmy@pobox.com> | 2021-08-30 20:31:42 +0100 |
|---|---|---|
| committer | Denys Vlasenko <vda.linux@googlemail.com> | 2021-09-02 17:49:00 +0200 |
| commit | 4a36ef11ac4d46ae651cbedc440ca6853415283a (patch) | |
| tree | 3e6fb84aa490cc05b6918c9c635df4d4f4198f95 /shell | |
| parent | f02691939eba5c043a90c0f1f428d4124dc83a1c (diff) | |
ash: regressions in process substitution
Stacy Harper reports that this script:
test() { . /tmp/bb_test; }
echo "export TEST=foo" >/tmp/bb_test
test 2>/dev/null
echo "$TEST"
correctly prints 'foo' in BusyBox 1.33 but hangs in 1.34.
Bisection suggested the problem was caused by commit a1b0d3856 (ash: add
process substitution in bash-compatibility mode). Removing the call to
unwindredir() in cmdloop() introduced in that commit makes the script
work again.
Additionally, these examples of process substitution:
while true; do cat <(echo hi); done
f() { while true; do cat <(echo hi); done }
f
result in running out of file descriptors. This is a regression from
v5 of the process substitution patch caused by changes to evalcommand()
not being transferred to v6.
function old new delta
static.pushredir - 99 +99
evalcommand 1729 1750 +21
exitreset 69 86 +17
cmdloop 372 365 -7
unwindredir 28 - -28
pushredir 112 - -112
------------------------------------------------------------------------------
(add/remove: 1/2 grow/shrink: 2/1 up/down: 137/-147) Total: -10 bytes
Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Diffstat (limited to 'shell')
| -rw-r--r-- | shell/ash.c | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/shell/ash.c b/shell/ash.c index b5947147a..53c140930 100644 --- a/shell/ash.c +++ b/shell/ash.c @@ -10278,6 +10278,9 @@ evalcommand(union node *cmd, int flags) /* First expand the arguments. */ TRACE(("evalcommand(0x%lx, %d) called\n", (long)cmd, flags)); +#if BASH_PROCESS_SUBST + redir_stop = redirlist; +#endif file_stop = g_parsefile; back_exitstatus = 0; @@ -10356,7 +10359,11 @@ evalcommand(union node *cmd, int flags) lastarg = nargv[-1]; expredir(cmd->ncmd.redirect); +#if !BASH_PROCESS_SUBST redir_stop = pushredir(cmd->ncmd.redirect); +#else + pushredir(cmd->ncmd.redirect); +#endif preverrout_fd = 2; if (BASH_XTRACEFD && xflag) { /* NB: bash closes fd == $BASH_XTRACEFD when it is changed. @@ -13477,9 +13484,6 @@ cmdloop(int top) if (doing_jobctl) showjobs(SHOW_CHANGED|SHOW_STDERR); #endif -#if BASH_PROCESS_SUBST - unwindredir(NULL); -#endif inter = 0; if (iflag && top) { inter++; |