extern struct stats stats;
extern int verbose;
+/* there's probably never more than at most 2 outstanding child processes,
+ * but set it higher just in case.
+ */
+#define MAXCHILDPROCS 5
+
+struct pid_status {
+ pid_t pid;
+ int status;
+} pid_stat_table[MAXCHILDPROCS];
+
static void show_malloc_stats(void);
/****************************************************************************
****************************************************************************/
void wait_process(pid_t pid, int *status)
{
- while (waitpid(pid, status, WNOHANG) == 0) {
+ pid_t waited_pid;
+ int cnt;
+
+ while ((waited_pid = waitpid(pid, status, WNOHANG)) == 0) {
msleep(20);
io_flush();
}
+ if ((waited_pid == -1) && (errno == ECHILD)) {
+ /* status of requested child no longer available.
+ * check to see if it was processed by the sigchld_handler.
+ */
+ for (cnt = 0; cnt < MAXCHILDPROCS; cnt++) {
+ if (pid == pid_stat_table[cnt].pid) {
+ *status = pid_stat_table[cnt].status;
+ pid_stat_table[cnt].pid = 0;
+ break;
+ }
+ }
+ }
+
/* TODO: If the child exited on a signal, then log an
* appropriate error message. Perhaps we should also accept a
* message describing the purpose of the child. Also indicate
}
io_flush();
+ io_set_error_fd(-1);
kill(pid, SIGUSR2);
wait_process(pid, &status);
return status;
static RETSIGTYPE sigchld_handler(int UNUSED(val)) {
#ifdef WNOHANG
- while (waitpid(-1, NULL, WNOHANG) > 0) ;
+ int cnt, status;
+ pid_t pid;
+ /* An empty waitpid() loop was put here by Tridge and we could never
+ * get him to explain why he put it in, so rather than taking it
+ * out we're instead saving the child exit statuses for later use.
+ * The waitpid() loop presumably eliminates all possibility of leaving
+ * zombie children, maybe that's why he did it.
+ */
+ while ((pid = waitpid(-1, &status, WNOHANG)) > 0) {
+ /* save the child's exit status */
+ for (cnt = 0; cnt < MAXCHILDPROCS; cnt++) {
+ if (pid_stat_table[cnt].pid == 0) {
+ pid_stat_table[cnt].pid = pid;
+ pid_stat_table[cnt].status = status;
+ break;
+ }
+ }
+ }
#endif
}