hush: make "wait %1" work even if the job is dead
Example script:
sleep 1 | (sleep 1;exit 3) &
sleep 2
echo Zero:$?
wait %1
echo Three:$?
function old new delta
clean_up_last_dead_job - 24 +24
process_wait_result 426 447 +21
builtin_wait 285 293 +8
insert_job_into_table 264 269 +5
builtin_jobs 68 73 +5
remove_job_from_table 59 57 -2
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 4/1 up/down: 63/-2) Total: 61 bytes
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/shell/hush.c b/shell/hush.c
index af5c260..b76351f 100644
--- a/shell/hush.c
+++ b/shell/hush.c
@@ -7237,11 +7237,42 @@
return pi->cmdtext;
}
+static void remove_job_from_table(struct pipe *pi)
+{
+ struct pipe *prev_pipe;
+
+ if (pi == G.job_list) {
+ G.job_list = pi->next;
+ } else {
+ prev_pipe = G.job_list;
+ while (prev_pipe->next != pi)
+ prev_pipe = prev_pipe->next;
+ prev_pipe->next = pi->next;
+ }
+ G.last_jobid = 0;
+ if (G.job_list)
+ G.last_jobid = G.job_list->jobid;
+}
+
+static void delete_finished_job(struct pipe *pi)
+{
+ remove_job_from_table(pi);
+ free_pipe(pi);
+}
+
+static void clean_up_last_dead_job(void)
+{
+ if (G.job_list && !G.job_list->alive_cmds)
+ delete_finished_job(G.job_list);
+}
+
static void insert_job_into_table(struct pipe *pi)
{
struct pipe *job, **jobp;
int i;
+ clean_up_last_dead_job();
+
/* Find the end of the list, and find next job ID to use */
i = 0;
jobp = &G.job_list;
@@ -7267,30 +7298,6 @@
printf("[%u] %u %s\n", job->jobid, (unsigned)job->cmds[0].pid, job->cmdtext);
G.last_jobid = job->jobid;
}
-
-static void remove_job_from_table(struct pipe *pi)
-{
- struct pipe *prev_pipe;
-
- if (pi == G.job_list) {
- G.job_list = pi->next;
- } else {
- prev_pipe = G.job_list;
- while (prev_pipe->next != pi)
- prev_pipe = prev_pipe->next;
- prev_pipe->next = pi->next;
- }
- if (G.job_list)
- G.last_jobid = G.job_list->jobid;
- else
- G.last_jobid = 0;
-}
-
-static void delete_finished_job(struct pipe *pi)
-{
- remove_job_from_table(pi);
- free_pipe(pi);
-}
#endif /* JOB */
static int job_exited_or_stopped(struct pipe *pi)
@@ -7415,14 +7422,22 @@
pi->cmds[i].pid = 0;
pi->alive_cmds--;
if (!pi->alive_cmds) {
- if (G_interactive_fd)
+ if (G_interactive_fd) {
printf(JOB_STATUS_FORMAT, pi->jobid,
"Done", pi->cmdtext);
- delete_finished_job(pi);
-//bash deletes finished jobs from job table only in interactive mode, after "jobs" cmd,
-//or if pid of a new process matches one of the old ones
-//(see cleanup_dead_jobs(), delete_old_job(), J_NOTIFIED in bash source).
-//Testcase script: "(exit 3) & sleep 1; wait %1; echo $?" prints 3 in bash.
+ delete_finished_job(pi);
+ } else {
+/*
+ * bash deletes finished jobs from job table only in interactive mode,
+ * after "jobs" cmd, or if pid of a new process matches one of the old ones
+ * (see cleanup_dead_jobs(), delete_old_job(), J_NOTIFIED in bash source).
+ * Testcase script: "(exit 3) & sleep 1; wait %1; echo $?" prints 3 in bash.
+ * We only retain one "dead" job, if it's the single job on the list.
+ * This covers most of real-world scenarios where this is useful.
+ */
+ if (pi != G.job_list)
+ delete_finished_job(pi);
+ }
}
} else {
/* child stopped */
@@ -9696,6 +9711,9 @@
printf(JOB_STATUS_FORMAT, job->jobid, status_string, job->cmdtext);
}
+
+ clean_up_last_dead_job();
+
return EXIT_SUCCESS;
}
@@ -9939,17 +9957,12 @@
wait_pipe = parse_jobspec(*argv);
if (wait_pipe) {
ret = job_exited_or_stopped(wait_pipe);
- if (ret < 0)
+ if (ret < 0) {
ret = wait_for_child_or_signal(wait_pipe, 0);
-//bash immediately deletes finished jobs from job table only in interactive mode,
-//we _always_ delete them at once. If we'd start keeping some dead jobs, this
-//(and more) would be necessary to avoid accumulating dead jobs:
-# if 0
- else {
- if (!wait_pipe->alive_cmds)
- delete_finished_job(wait_pipe);
+ } else {
+ /* waiting on "last dead job" removes it */
+ clean_up_last_dead_job();
}
-# endif
}
/* else: parse_jobspec() already emitted error msg */
continue;