Revert r63758 and related commits

The change is unstable on Windows. Please re-commit it when it correctly
supports Windows.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@63852 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 43 insertions, 244 deletions

diff --git a/process.c b/process.c
index 695fd72119..12ea6eac86 100644
--- a/process.c
+++ b/process.c
@@ -885,6 +885,12 @@ pst_wcoredump(VALUE st)
 #endif
 }
 
+struct waitpid_arg {
+    rb_pid_t pid;
+    int flags;
+    int *st;
+};
+
 static rb_pid_t
 do_waitpid(rb_pid_t pid, int *st, int flags)
 {
@@ -897,263 +903,45 @@ do_waitpid(rb_pid_t pid, int *st, int flags)
 #endif
 }
 
-struct waitpid_state {
-    struct list_node wnode;
-    rb_execution_context_t *ec;
-    rb_nativethread_cond_t *cond;
-    rb_pid_t ret;
-    rb_pid_t pid;
-    int status;
-    int options;
-    int errnum;
-};
-
-void rb_native_mutex_lock(rb_nativethread_lock_t *);
-void rb_native_mutex_unlock(rb_nativethread_lock_t *);
-void rb_native_cond_signal(rb_nativethread_cond_t *);
-void rb_native_cond_wait(rb_nativethread_cond_t *, rb_nativethread_lock_t *);
-rb_nativethread_cond_t *rb_sleep_cond_get(const rb_execution_context_t *);
-void rb_sleep_cond_put(rb_nativethread_cond_t *);
-
-static void
-waitpid_notify(struct waitpid_state *w, rb_pid_t ret)
-{
-    w->ret = ret;
-    list_del_init(&w->wnode);
-    rb_native_cond_signal(w->cond);
-}
-
-#ifdef _WIN32 /* for spawnvp result from mjit.c */
-#  define waitpid_sys(pid,status,options) \
-	  (WaitForSingleObject((HANDLE)(pid), 0),\
-	   GetExitCodeProcess((HANDLE)(pid), (LPDWORD)(status)))
-#else
-#  define waitpid_sys(pid,status,options) do_waitpid((pid),(status),(options))
-#endif
-
-/* called by timer thread */
-static void
-waitpid_each(struct list_head *head)
-{
-    struct waitpid_state *w = 0, *next;
-
-    list_for_each_safe(head, w, next, wnode) {
-        rb_pid_t ret;
-
-        if (w->ec)
-            ret = do_waitpid(w->pid, &w->status, w->options | WNOHANG);
-        else
-            ret = waitpid_sys(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);
-
-            rb_native_mutex_lock(&th->interrupt_lock);
-            waitpid_notify(w, ret);
-            rb_native_mutex_unlock(&th->interrupt_lock);
-        }
-        else { /* ruby_waitpid_locked */
-            waitpid_notify(w, ret);
-        }
-    }
-}
-
-void
-ruby_waitpid_all(rb_vm_t *vm)
-{
-    rb_native_mutex_lock(&vm->waitpid_lock);
-    waitpid_each(&vm->waiting_pids);
-    if (list_empty(&vm->waiting_pids)) {
-        waitpid_each(&vm->waiting_grps);
-    }
-    rb_native_mutex_unlock(&vm->waitpid_lock);
-}
-
-static void
-waitpid_state_init(struct waitpid_state *w, rb_pid_t pid, int options)
-{
-    w->ret = 0;
-    w->pid = pid;
-    w->options = options;
-}
-
-/*
- * must be called with vm->waitpid_lock held, this is not interruptible
- */
-rb_pid_t
-ruby_waitpid_locked(rb_vm_t *vm, rb_pid_t pid, int *status, int options,
-                    rb_nativethread_cond_t *cond)
-{
-    struct waitpid_state w;
-
-    assert(!ruby_thread_has_gvl_p() && "must not have GVL");
-
-    waitpid_state_init(&w, pid, options);
-    if (w.pid > 0 || list_empty(&vm->waiting_pids))
-        w.ret = do_waitpid(w.pid, &w.status, w.options | WNOHANG);
-    if (w.ret) {
-        if (w.ret == -1) w.errnum = errno;
-    }
-    else {
-        w.cond = cond;
-        w.ec = 0;
-        list_add(w.pid > 0 ? &vm->waiting_pids : &vm->waiting_grps, &w.wnode);
-        do {
-            rb_native_cond_wait(w.cond, &vm->waitpid_lock);
-        } while (!w.ret);
-        list_del(&w.wnode);
-    }
-    if (status) {
-        *status = w.status;
-    }
-    if (w.ret == -1) errno = w.errnum;
-    return w.ret;
-}
-
-static void
-waitpid_wake(void *x)
-{
-    struct waitpid_state *w = x;
-
-    /* th->interrupt_lock is already held by rb_threadptr_interrupt_common */
-    rb_native_cond_signal(w->cond);
-}
-
 static void *
-waitpid_nogvl(void *x)
+rb_waitpid_blocking(void *data)
 {
-    struct waitpid_state *w = x;
-    rb_thread_t *th = rb_ec_thread_ptr(w->ec);
-
-    rb_native_mutex_lock(&th->interrupt_lock);
-    /*
-     * We must check again before waiting, timer-thread may change w->ret
-     * by the time we enter this.  And we may also be interrupted.
-     */
-    if (!w->ret && !RUBY_VM_INTERRUPTED_ANY(w->ec)) {
-        if (SIGCHLD_LOSSY) {
-            rb_thread_wakeup_timer_thread();
-        }
-        rb_native_cond_wait(w->cond, &th->interrupt_lock);
-    }
-    rb_native_mutex_unlock(&th->interrupt_lock);
-
-    return 0;
+    struct waitpid_arg *arg = data;
+    rb_pid_t result = do_waitpid(arg->pid, arg->st, arg->flags);
+    return (void *)(VALUE)result;
 }
 
-static VALUE
-waitpid_sleep(VALUE x)
-{
-    struct waitpid_state *w = (struct waitpid_state *)x;
-
-    while (!w->ret) {
-        rb_thread_call_without_gvl(waitpid_nogvl, w, waitpid_wake, w);
-    }
-
-    return Qfalse;
-}
-
-static VALUE
-waitpid_cleanup(VALUE x)
-{
-    struct waitpid_state *w = (struct waitpid_state *)x;
-
-    if (w->ret == 0) {
-        rb_vm_t *vm = rb_ec_vm_ptr(w->ec);
-
-        rb_native_mutex_lock(&vm->waitpid_lock);
-        list_del(&w->wnode);
-        rb_native_mutex_unlock(&vm->waitpid_lock);
-    }
-    rb_sleep_cond_put(w->cond);
-
-    return Qfalse;
-}
-
-static void
-waitpid_wait(struct waitpid_state *w)
-{
-    rb_vm_t *vm = rb_ec_vm_ptr(w->ec);
-
-    /*
-     * Lock here to prevent do_waitpid from stealing work from the
-     * ruby_waitpid_locked done by mjit workers since mjit works
-     * outside of GVL
-     */
-    rb_native_mutex_lock(&vm->waitpid_lock);
-
-    if (w->pid > 0 || list_empty(&vm->waiting_pids))
-        w->ret = do_waitpid(w->pid, &w->status, w->options | WNOHANG);
-    if (w->ret) {
-        w->cond = 0;
-        if (w->ret == -1) w->errnum = errno;
-    }
-    else if (w->options & WNOHANG) {
-        w->cond = 0;
-    }
-    else {
-        w->cond = rb_sleep_cond_get(w->ec);
-        /* order matters, favor specified PIDs rather than -1 or 0 */
-        list_add(w->pid > 0 ? &vm->waiting_pids : &vm->waiting_grps, &w->wnode);
-    }
-
-    rb_native_mutex_unlock(&vm->waitpid_lock);
-
-    if (w->cond) {
-        rb_ensure(waitpid_sleep, (VALUE)w, waitpid_cleanup, (VALUE)w);
-    }
-}
-
-static void *
-waitpid_blocking_no_SIGCHLD(void *x)
-{
-    struct waitpid_state *w = x;
-
-    w->ret = do_waitpid(w->pid, &w->status, w->options);
-
-    return 0;
-}
-
-static void
-waitpid_no_SIGCHLD(struct waitpid_state *w)
+static rb_pid_t
+do_waitpid_nonblocking(rb_pid_t pid, int *st, int flags)
 {
-    if (w->options & WNOHANG) {
-        w->ret = do_waitpid(w->pid, &w->status, w->options);
-    }
-    else {
-        do {
-            rb_thread_call_without_gvl(waitpid_blocking_no_SIGCHLD, w,
-                                       RUBY_UBF_PROCESS, 0);
-        } while (w->ret < 0 && errno == EINTR && (RUBY_VM_CHECK_INTS(w->ec),1));
-    }
-    if (w->ret == -1)
-        w->errnum = errno;
+    void *result;
+    struct waitpid_arg arg;
+    arg.pid = pid;
+    arg.st = st;
+    arg.flags = flags;
+    result = rb_thread_call_without_gvl(rb_waitpid_blocking, &arg,
+					RUBY_UBF_PROCESS, 0);
+    return (rb_pid_t)(VALUE)result;
 }
 
 rb_pid_t
 rb_waitpid(rb_pid_t pid, int *st, int flags)
 {
-    struct waitpid_state w;
+    rb_pid_t result;
 
-    waitpid_state_init(&w, pid, flags);
-    w.ec = GET_EC();
-
-    if (RUBY_SIGCHLD || SIGCHLD_LOSSY) {
-        waitpid_wait(&w);
+    if (flags & WNOHANG) {
+	result = do_waitpid(pid, st, flags);
     }
     else {
-        waitpid_no_SIGCHLD(&w);
+	while ((result = do_waitpid_nonblocking(pid, st, flags)) < 0 &&
+	       (errno == EINTR)) {
+	    RUBY_VM_CHECK_INTS(GET_EC());
+	}
     }
-
-    if (st) *st = w.status;
-    if (w.ret > 0) {
-	rb_last_status_set(w.status, w.ret);
+    if (result > 0) {
+	rb_last_status_set(*st, result);
     }
-    if (w.ret == -1) errno = w.errnum;
-    return w.ret;
+    return result;
 }
 
 
@@ -3807,8 +3595,6 @@ disable_child_handler_fork_child(struct child_handler_disabler_state *old, char
 	}
     }
 
-    /* non-Ruby child process, ensure cmake can see SIGCHLD */
-    sigemptyset(&old->sigmask);
     ret = sigprocmask(SIG_SETMASK, &old->sigmask, NULL); /* async-signal-safe */
     if (ret != 0) {
         ERRMSG("sigprocmask");
@@ -4300,6 +4086,16 @@ rb_f_system(int argc, VALUE *argv)
     VALUE execarg_obj;
     struct rb_execarg *eargp;
 
+#if defined(SIGCLD) && !defined(SIGCHLD)
+# define SIGCHLD SIGCLD
+#endif
+
+#ifdef SIGCHLD
+    RETSIGTYPE (*chfunc)(int);
+
+    rb_last_status_clear();
+    chfunc = signal(SIGCHLD, SIG_DFL);
+#endif
     execarg_obj = rb_execarg_new(argc, argv, TRUE, TRUE);
     pid = rb_execarg_spawn(execarg_obj, NULL, 0);
 #if defined(HAVE_WORKING_FORK) || defined(HAVE_SPAWNV)
@@ -4310,6 +4106,9 @@ rb_f_system(int argc, VALUE *argv)
             rb_sys_fail("Another thread waited the process started by system().");
     }
 #endif
+#ifdef SIGCHLD
+    signal(SIGCHLD, chfunc);
+#endif
     TypedData_Get_Struct(execarg_obj, struct rb_execarg, &exec_arg_data_type, eargp);
     if (pid < 0) {
         if (eargp->exception) {