git: 3d73146baeb9 - main - pwait: Add an option to print remaining processes
Date: Tue, 28 Oct 2025 11:57:43 UTC
The branch main has been updated by des:
URL: https://cgit.FreeBSD.org/src/commit/?id=3d73146baeb933fe955c7496572b483a9f92914c
commit 3d73146baeb933fe955c7496572b483a9f92914c
Author: Dag-Erling Smørgrav <des@FreeBSD.org>
AuthorDate: 2025-10-28 11:56:36 +0000
Commit: Dag-Erling Smørgrav <des@FreeBSD.org>
CommitDate: 2025-10-28 11:57:16 +0000
pwait: Add an option to print remaining processes
* On startup, insert all valid PIDs into a tree.
* In our main loop, whenever a process terminates, remove its PID
from the tree.
* On exit, if the -p flag was specified, print the remaining PIDs.
MFC after: 3 days
Reviewed by: bcr, markj
Differential Revision: https://reviews.freebsd.org/D53293
---
bin/pwait/pwait.1 | 6 ++-
bin/pwait/pwait.c | 98 ++++++++++++++++++++++++++++---------------
bin/pwait/tests/pwait_test.sh | 38 +++++++++++++++++
3 files changed, 107 insertions(+), 35 deletions(-)
diff --git a/bin/pwait/pwait.1 b/bin/pwait/pwait.1
index 83ac8bcef317..d92b829b1d6a 100644
--- a/bin/pwait/pwait.1
+++ b/bin/pwait/pwait.1
@@ -30,7 +30,7 @@
.\" USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
.\" OF SUCH DAMAGE.
.\"
-.Dd January 21, 2021
+.Dd October 22, 2025
.Dt PWAIT 1
.Os
.Sh NAME
@@ -39,7 +39,7 @@
.Sh SYNOPSIS
.Nm
.Op Fl t Ar duration
-.Op Fl ov
+.Op Fl opv
.Ar pid
\&...
.Sh DESCRIPTION
@@ -51,6 +51,8 @@ The following option is available:
.Bl -tag -width indent
.It Fl o
Exit when any of the given processes has terminated.
+.It Fl p
+On exit, print a list of processes that have not terminated.
.It Fl t Ar duration
If any process is still running after
.Ar duration ,
diff --git a/bin/pwait/pwait.c b/bin/pwait/pwait.c
index 27f4c8e9858d..59bf0eb93ced 100644
--- a/bin/pwait/pwait.c
+++ b/bin/pwait/pwait.c
@@ -33,7 +33,9 @@
#include <sys/types.h>
#include <sys/event.h>
+#include <sys/sysctl.h>
#include <sys/time.h>
+#include <sys/tree.h>
#include <sys/wait.h>
#include <err.h>
@@ -46,10 +48,25 @@
#include <sysexits.h>
#include <unistd.h>
+struct pid {
+ RB_ENTRY(pid) entry;
+ pid_t pid;
+};
+
+static int
+pidcmp(const struct pid *a, const struct pid *b)
+{
+ return (a->pid > b->pid ? 1 : a->pid < b->pid ? -1 : 0);
+}
+
+RB_HEAD(pidtree, pid);
+static struct pidtree pids = RB_INITIALIZER(&pids);
+RB_GENERATE_STATIC(pidtree, pid, entry, pidcmp);
+
static void
usage(void)
{
- fprintf(stderr, "usage: pwait [-t timeout] [-ov] pid ...\n");
+ fprintf(stderr, "usage: pwait [-t timeout] [-opv] pid ...\n");
exit(EX_USAGE);
}
@@ -61,22 +78,28 @@ main(int argc, char *argv[])
{
struct itimerval itv;
struct kevent *e;
+ struct pid k, *p;
char *end, *s;
double timeout;
+ size_t sz;
long pid;
pid_t mypid;
- int i, kq, n, nleft, opt, status;
- bool oflag, tflag, verbose;
+ int i, kq, n, ndone, nleft, opt, pid_max, ret, status;
+ bool oflag, pflag, tflag, verbose;
oflag = false;
+ pflag = false;
tflag = false;
verbose = false;
memset(&itv, 0, sizeof(itv));
- while ((opt = getopt(argc, argv, "ot:v")) != -1) {
+ while ((opt = getopt(argc, argv, "opt:v")) != -1) {
switch (opt) {
case 'o':
- oflag = 1;
+ oflag = true;
+ break;
+ case 'p':
+ pflag = true;
break;
case 't':
tflag = true;
@@ -128,16 +151,17 @@ main(int argc, char *argv[])
usage();
}
- kq = kqueue();
- if (kq == -1) {
+ if ((kq = kqueue()) < 0)
err(EX_OSERR, "kqueue");
- }
- e = malloc((argc + tflag) * sizeof(struct kevent));
- if (e == NULL) {
+ sz = sizeof(pid_max);
+ if (sysctlbyname("kern.pid_max", &pid_max, &sz, NULL, 0) != 0) {
+ pid_max = 99999;
+ }
+ if ((e = malloc((argc + tflag) * sizeof(*e))) == NULL) {
err(EX_OSERR, "malloc");
}
- nleft = 0;
+ ndone = nleft = 0;
mypid = getpid();
for (n = 0; n < argc; n++) {
s = argv[n];
@@ -147,7 +171,7 @@ main(int argc, char *argv[])
}
errno = 0;
pid = strtol(s, &end, 10);
- if (pid < 0 || *end != '\0' || errno != 0) {
+ if (pid < 0 || pid > pid_max || *end != '\0' || errno != 0) {
warnx("%s: bad process id", s);
continue;
}
@@ -155,27 +179,29 @@ main(int argc, char *argv[])
warnx("%s: skipping my own pid", s);
continue;
}
- for (i = 0; i < nleft; i++) {
- if (e[i].ident == (uintptr_t)pid) {
- break;
- }
+ if ((p = malloc(sizeof(*p))) == NULL) {
+ err(EX_OSERR, NULL);
}
- if (i < nleft) {
+ p->pid = pid;
+ if (RB_INSERT(pidtree, &pids, p) != NULL) {
/* Duplicate. */
+ free(p);
continue;
}
EV_SET(e + nleft, pid, EVFILT_PROC, EV_ADD, NOTE_EXIT, 0, NULL);
if (kevent(kq, e + nleft, 1, NULL, 0, NULL) == -1) {
+ if (errno != ESRCH)
+ err(EX_OSERR, "kevent()");
warn("%ld", pid);
- if (oflag) {
- exit(EX_OK);
- }
+ RB_REMOVE(pidtree, &pids, p);
+ free(p);
+ ndone++;
} else {
nleft++;
}
}
- if (nleft > 0 && tflag) {
+ if ((ndone == 0 || !oflag) && nleft > 0 && tflag) {
/*
* Explicitly detect SIGALRM so that an exit status of 124
* can be returned rather than 142.
@@ -190,7 +216,8 @@ main(int argc, char *argv[])
err(EX_OSERR, "setitimer");
}
}
- while (nleft > 0) {
+ ret = EX_OK;
+ while ((ndone == 0 || !oflag) && ret == EX_OK && nleft > 0) {
n = kevent(kq, NULL, 0, e, nleft + tflag, NULL);
if (n == -1) {
err(EX_OSERR, "kevent");
@@ -200,29 +227,34 @@ main(int argc, char *argv[])
if (verbose) {
printf("timeout\n");
}
- exit(124);
+ ret = 124;
}
+ pid = e[i].ident;
if (verbose) {
status = e[i].data;
if (WIFEXITED(status)) {
printf("%ld: exited with status %d.\n",
- (long)e[i].ident,
- WEXITSTATUS(status));
+ pid, WEXITSTATUS(status));
} else if (WIFSIGNALED(status)) {
printf("%ld: killed by signal %d.\n",
- (long)e[i].ident,
- WTERMSIG(status));
+ pid, WTERMSIG(status));
} else {
- printf("%ld: terminated.\n",
- (long)e[i].ident);
+ printf("%ld: terminated.\n", pid);
}
}
- if (oflag) {
- exit(EX_OK);
+ k.pid = pid;
+ if ((p = RB_FIND(pidtree, &pids, &k)) != NULL) {
+ RB_REMOVE(pidtree, &pids, p);
+ free(p);
+ ndone++;
}
--nleft;
}
}
-
- exit(EX_OK);
+ if (pflag) {
+ RB_FOREACH(p, pidtree, &pids) {
+ printf("%d\n", p->pid);
+ }
+ }
+ exit(ret);
}
diff --git a/bin/pwait/tests/pwait_test.sh b/bin/pwait/tests/pwait_test.sh
index 66bdd6981704..d31ca21cff93 100644
--- a/bin/pwait/tests/pwait_test.sh
+++ b/bin/pwait/tests/pwait_test.sh
@@ -310,6 +310,43 @@ or_flag_cleanup()
wait $p2 $p4 $p6 >/dev/null 2>&1
}
+atf_test_case print
+print_head()
+{
+ atf_set "descr" "Test the -p flag"
+}
+
+print_body()
+{
+ sleep 1 &
+ p1=$!
+
+ sleep 5 &
+ p5=$!
+
+ sleep 10 &
+ p10=$!
+
+ atf_check \
+ -o inline:"$p5\n$p10\n" \
+ -s exit:124 \
+ pwait -t 2 -p $p10 $p5 $p1 $p5 $p10
+
+ atf_check \
+ -e inline:"kill: $p1: No such process\n" \
+ -s exit:1 \
+ kill -0 $p1
+
+ atf_check kill -0 $p5
+ atf_check kill -0 $p10
+}
+
+print_cleanup()
+{
+ kill $p1 $p5 $p10 >/dev/null 2>&1
+ wait $p1 $p5 $p10 >/dev/null 2>&1
+}
+
atf_init_test_cases()
{
atf_add_test_case basic
@@ -318,4 +355,5 @@ atf_init_test_cases()
atf_add_test_case timeout_no_timeout
atf_add_test_case timeout_many
atf_add_test_case or_flag
+ atf_add_test_case print
}