Add better timeout mechanism for running commands.
Change-Id: I60fc9e7d59c3e0e4b8b2f69f79c6903240bfd131
diff --git a/cmds/dumpstate/utils.c b/cmds/dumpstate/utils.c
index 3e0b24b..6beb5ed 100644
--- a/cmds/dumpstate/utils.c
+++ b/cmds/dumpstate/utils.c
@@ -301,6 +301,50 @@
return (int64_t)ts.tv_sec * NANOS_PER_SEC + ts.tv_nsec;
}
+bool waitpid_with_timeout(pid_t pid, int timeout_seconds, int* status) {
+ sigset_t child_mask, old_mask;
+ sigemptyset(&child_mask);
+ sigaddset(&child_mask, SIGCHLD);
+
+ if (sigprocmask(SIG_BLOCK, &child_mask, &old_mask) == -1) {
+ printf("*** sigprocmask failed: %s\n", strerror(errno));
+ return false;
+ }
+
+ struct timespec ts;
+ ts.tv_sec = timeout_seconds;
+ ts.tv_nsec = 0;
+ int ret = TEMP_FAILURE_RETRY(sigtimedwait(&child_mask, NULL, &ts));
+ int saved_errno = errno;
+ // Set the signals back the way they were.
+ if (sigprocmask(SIG_SETMASK, &old_mask, NULL) == -1) {
+ printf("*** sigprocmask failed: %s\n", strerror(errno));
+ if (ret == 0) {
+ return false;
+ }
+ }
+ if (ret == -1) {
+ errno = saved_errno;
+ if (errno == EAGAIN) {
+ errno = ETIMEDOUT;
+ } else {
+ printf("*** sigtimedwait failed: %s\n", strerror(errno));
+ }
+ return false;
+ }
+
+ pid_t child_pid = waitpid(pid, status, WNOHANG);
+ if (child_pid != pid) {
+ if (child_pid != -1) {
+ printf("*** Waiting for pid %d, got pid %d instead\n", pid, child_pid);
+ } else {
+ printf("*** waitpid failed: %s\n", strerror(errno));
+ }
+ return false;
+ }
+ return true;
+}
+
/* forks a command and waits for it to finish */
int run_command(const char *title, int timeout_seconds, const char *command, ...) {
fflush(stdout);
@@ -345,28 +389,35 @@
}
/* handle parent case */
- for (;;) {
- int status;
- pid_t p = waitpid(pid, &status, WNOHANG);
- int64_t elapsed = nanotime() - start;
- if (p == pid) {
- if (WIFSIGNALED(status)) {
- printf("*** %s: Killed by signal %d\n", command, WTERMSIG(status));
- } else if (WIFEXITED(status) && WEXITSTATUS(status) > 0) {
- printf("*** %s: Exit code %d\n", command, WEXITSTATUS(status));
+ int status;
+ bool ret = waitpid_with_timeout(pid, timeout_seconds, &status);
+ uint64_t elapsed = nanotime() - start;
+ if (!ret) {
+ if (errno == ETIMEDOUT) {
+ printf("*** %s: Timed out after %.3fs (killing pid %d)\n", command,
+ (float) elapsed / NANOS_PER_SEC, pid);
+ } else {
+ printf("*** %s: Error after %.4fs (killing pid %d)\n", command,
+ (float) elapsed / NANOS_PER_SEC, pid);
+ }
+ kill(pid, SIGTERM);
+ if (!waitpid_with_timeout(pid, 5, NULL)) {
+ kill(pid, SIGKILL);
+ if (!waitpid_with_timeout(pid, 5, NULL)) {
+ printf("*** %s: Cannot kill %d even with SIGKILL.\n", command, pid);
}
- if (title) printf("[%s: %.3fs elapsed]\n\n", command, (float)elapsed / NANOS_PER_SEC);
- return status;
}
-
- if (timeout_seconds && elapsed / NANOS_PER_SEC > timeout_seconds) {
- printf("*** %s: Timed out after %.3fs (killing pid %d)\n", command, (float) elapsed / NANOS_PER_SEC, pid);
- kill(pid, SIGTERM);
- return -1;
- }
-
- usleep(100000); // poll every 0.1 sec
+ return -1;
}
+
+ if (WIFSIGNALED(status)) {
+ printf("*** %s: Killed by signal %d\n", command, WTERMSIG(status));
+ } else if (WIFEXITED(status) && WEXITSTATUS(status) > 0) {
+ printf("*** %s: Exit code %d\n", command, WEXITSTATUS(status));
+ }
+ if (title) printf("[%s: %.3fs elapsed]\n\n", command, (float)elapsed / NANOS_PER_SEC);
+
+ return status;
}
size_t num_props = 0;