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-rw-r--r--pause/pause.c69
1 files changed, 69 insertions, 0 deletions
diff --git a/pause/pause.c b/pause/pause.c
new file mode 100644
index 000000000..1e363bd7a
--- /dev/null
+++ b/pause/pause.c
@@ -0,0 +1,69 @@
+/*
+Copyright 2016 The Kubernetes Authors.
+Copyright 2021 The Podman Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+#define STRINGIFY(x) #x
+#define VERSION_STRING(x) STRINGIFY(x)
+
+#ifndef VERSION
+#define VERSION HEAD
+#endif
+
+static void sigdown(int signo) {
+ psignal(signo, "Shutting down, got signal");
+ exit(0);
+}
+
+static void sigreap(int signo) {
+ while (waitpid(-1, NULL, WNOHANG) > 0)
+ ;
+}
+
+int main(int argc, char **argv) {
+ int i;
+ for (i = 1; i < argc; ++i) {
+ if (!strcasecmp(argv[i], "-v")) {
+ printf("pause.c %s\n", VERSION_STRING(VERSION));
+ return 0;
+ }
+ }
+
+ if (getpid() != 1)
+ /* Not an error because pause sees use outside of infra containers. */
+ fprintf(stderr, "Warning: pause should be the first process\n");
+
+ if (sigaction(SIGINT, &(struct sigaction){.sa_handler = sigdown}, NULL) < 0)
+ return 1;
+ if (sigaction(SIGTERM, &(struct sigaction){.sa_handler = sigdown}, NULL) < 0)
+ return 2;
+ if (sigaction(SIGCHLD, &(struct sigaction){.sa_handler = sigreap,
+ .sa_flags = SA_NOCLDSTOP},
+ NULL) < 0)
+ return 3;
+
+ for (;;)
+ pause();
+ fprintf(stderr, "Error: infinite loop terminated\n");
+ return 42;
+}