[PATCH 8/8] wip testing

[Eric Wong <e@80x24.org>]

---
 mjit.c    |  5 +++--
 process.c | 12 +++++++++---
 2 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/mjit.c b/mjit.c
index a550d1aabd..2e11395851 100644
--- a/mjit.c
+++ b/mjit.c
@@ -421,8 +421,9 @@ exec_process(const char *path, char *const argv[])
         pid_t r = vm ? ruby_waitpid_locked(vm, pid, &stat, 0, &cond)
                      : waitpid(pid, &stat, 0);
         if (r == -1) {
-            if (errno == EINTR) continue; /* should never happen */
-            fprintf(stderr, "waitpid: %s\n", strerror(errno));
+            if (errno == EINTR) continue;
+            fprintf(stderr, "[%d] waitpid(%d): %s\n",
+                    getpid(), pid, strerror(errno));
             break;
         }
         else if (r == pid) {
diff --git a/process.c b/process.c
index 0b91b30075..ce1445fbaa 100644
--- a/process.c
+++ b/process.c
@@ -919,7 +919,6 @@ static void
 waitpid_notify(struct waitpid_state *w, pid_t ret)
 {
     w->ret = ret;
-    if (w->ret == -1) w->errnum = errno;
     list_del_init(&w->wnode);
     rb_native_cond_signal(w->cond);
 }
@@ -933,7 +932,9 @@ ruby_waitpid_all(rb_vm_t *vm)
     rb_native_mutex_lock(&vm->waitpid_lock);
     list_for_each_safe(&vm->waiting_pids, w, next, wnode) {
         pid_t ret = do_waitpid(w->pid, &w->status, w->options | WNOHANG);
+
         if (!ret) continue;
+        if (ret == -1) w->errnum = errno;
 
         if (w->ec) { /* rb_waitpid */
             rb_thread_t *th = rb_ec_thread_ptr(w->ec);
@@ -985,7 +986,7 @@ ruby_waitpid_locked(rb_vm_t *vm, rb_pid_t pid, int *status, int options,
     if (status) {
         *status = w.status;
     }
-    errno = w.errnum;
+    if (w.ret == -1) errno = w.errnum;
     return w.ret;
 }
 
@@ -1061,7 +1062,11 @@ waitpid_wait(struct waitpid_state *w)
     }
     else {
         w->cond = rb_sleep_cond_get(w->ec);
-        list_add(&vm->waiting_pids, &w->wnode);
+        /* order matters, favor specified PIDs rather than -1 or 0 */
+        if (w->pid > 0)
+          list_add(&vm->waiting_pids, &w->wnode);
+        else
+          list_add_tail(&vm->waiting_pids, &w->wnode);
     }
 
     rb_native_mutex_unlock(&vm->waitpid_lock);
@@ -1086,6 +1091,7 @@ rb_waitpid(rb_pid_t pid, int *st, int flags)
     if (result > 0) {
 	rb_last_status_set(*st, result);
     }
+    if (w.ret == -1) errno = w.errnum;
     return result;
 }
 
-- 
EW