--- /dev/null
+/*
+ * waitpid(1) - wait for process termination
+ *
+ * Copyright (C) 2022 Thomas Weißschuh <thomas@t-8ch.de>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it would be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include <sys/epoll.h>
+#include <assert.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <string.h>
+#include <unistd.h>
+#include <stdbool.h>
+#include <getopt.h>
+
+#include "pidfd-utils.h"
+#include "c.h"
+#include "nls.h"
+#include "xalloc.h"
+#include "strutils.h"
+#include "exitcodes.h"
+
+#define err_nosys(exitcode, ...) \
+ err(errno == ENOSYS ? EXIT_NOTSUPP : exitcode, __VA_ARGS__)
+
+static bool verbose = false;
+
+static pid_t *parse_pids(size_t n_strings, char * const *strings)
+{
+ pid_t *pids = xcalloc(n_strings, sizeof(*pids));
+
+ for (size_t i = 0; i < n_strings; i++)
+ pids[i] = strtopid_or_err(strings[i], _("failed to parse pid"));
+
+ return pids;
+}
+
+static int *open_pidfds(size_t n_pids, pid_t *pids)
+{
+ int *pidfds = xcalloc(n_pids, sizeof(*pidfds));
+
+ for (size_t i = 0; i < n_pids; i++) {
+ pidfds[i] = pidfd_open(pids[i], 0);
+ if (pidfds[i] == -1)
+ err_nosys(EXIT_FAILURE, _("could not open pid %u"), pids[i]);
+ }
+
+ return pidfds;
+}
+
+static void add_listeners(int epll, size_t n_pids, int * const pidfds)
+{
+ for (size_t i = 0; i < n_pids; i++) {
+ struct epoll_event evt = {
+ .events = EPOLLIN,
+ .data = { .u64 = i },
+ };
+ if (epoll_ctl(epll, EPOLL_CTL_ADD, pidfds[i], &evt))
+ err_nosys(EXIT_FAILURE, _("could not add listener"));
+ }
+}
+
+static void wait_for_exits(int epll, size_t n_pids, pid_t * const pids, int * const pidfds)
+{
+ while (n_pids) {
+ struct epoll_event evt;
+ int ret, fd;
+
+ ret = epoll_wait(epll, &evt, 1, -1);
+ if (ret == -1) {
+ if (errno == EINTR)
+ continue;
+ else
+ err_nosys(EXIT_FAILURE, _("failure during wait"));
+ }
+ if (verbose)
+ printf(_("PID %d finished\n"), pids[evt.data.u64]);
+ assert((size_t) ret <= n_pids);
+ fd = pidfds[evt.data.u64];
+ epoll_ctl(epll, EPOLL_CTL_DEL, fd, NULL);
+ n_pids -= ret;
+ }
+}
+
+static void __attribute__((__noreturn__)) usage(void)
+{
+ FILE *out = stdout;
+
+ fputs(USAGE_HEADER, out);
+ fprintf(out, _(" %s [options] pid...\n"), program_invocation_short_name);
+
+ fputs(USAGE_OPTIONS, out);
+ fputs(_(" -v, --verbose be more verbose\n"), out);
+
+ fputs(USAGE_SEPARATOR, out);
+ fprintf(out, USAGE_HELP_OPTIONS(23));
+
+ fprintf(out, USAGE_MAN_TAIL("waitpid(1)"));
+
+ exit(EXIT_SUCCESS);
+}
+
+static int parse_options(int argc, char **argv)
+{
+ int c;
+ static const struct option longopts[] = {
+ { "verbose", no_argument, NULL, 'v' },
+ { "version", no_argument, NULL, 'V' },
+ { "help", no_argument, NULL, 'h' },
+ { NULL, 0, NULL, 0 },
+ };
+
+ while ((c = getopt_long (argc, argv, "vVh", longopts, NULL)) != -1) {
+ switch (c) {
+ case 'v':
+ verbose = true;
+ break;
+ case 'V':
+ print_version(EXIT_SUCCESS);
+ case 'h':
+ usage();
+ default:
+ errtryhelp(EXIT_FAILURE);
+ }
+ }
+
+ return optind;
+}
+
+int main(int argc, char **argv)
+{
+ int pid_idx, epoll;
+ size_t n_pids;
+ int *pidfds;
+
+ setlocale(LC_ALL, "");
+ bindtextdomain(PACKAGE, LOCALEDIR);
+ textdomain(PACKAGE);
+
+ pid_idx = parse_options(argc, argv);
+ n_pids = argc - pid_idx;
+ if (!n_pids)
+ return EXIT_FAILURE;
+
+ pid_t *pids = parse_pids(argc - pid_idx, argv + pid_idx);
+
+ pidfds = open_pidfds(n_pids, pids);
+ epoll = epoll_create(n_pids);
+ if (epoll == -1)
+ err_nosys(EXIT_FAILURE, _("could not create epoll"));
+
+ add_listeners(epoll, n_pids, pidfds);
+ wait_for_exits(epoll, n_pids, pids, pidfds);
+}
--- /dev/null
+#!/bin/bash
+
+# Copyright (C) 2022 Thomas Weißschuh <thomas@t-8ch.de>
+#
+# This file is part of util-linux.
+#
+# This file is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This file is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+
+TS_TOPDIR="${0%/*}/../.."
+TS_DESC="waitpid"
+
+. "$TS_TOPDIR"/functions.sh
+ts_init "$*"
+
+ts_check_test_command "$TS_CMD_WAITPID"
+
+(sleep 0.2; echo 1 >> "$TS_OUTPUT") &
+BG1="$!"
+
+(sleep 0.1; echo 2 >> "$TS_OUTPUT") &
+BG2="$!"
+
+echo 3 >> "$TS_OUTPUT"
+"$TS_CMD_WAITPID" "$BG1" "$BG2"
+ts_skip_exitcode_not_supported
+
+echo 4 >> "$TS_OUTPUT"
+
+ts_finalize
projects / thirdparty / util-linux.git / commitdiff
