fix rktio destroy to release a pipe used for internal singals

Also, fix CS to desstroy a place's rktio instance when the place
exits.

Closes #3243

pkgs/racket-test-extra/tests/racket/many-places.rkt

@@ -0,0 +1,10 @@
+#lang racket/base
+(require racket/place)
+
+;; Try to catch a resource leak starting and finishing places.
+
+(for ([i (in-range 256)])
+  (printf "~s\n" i)
+  (map place-wait
+       (for/list ([i 4])
+         (dynamic-place ''#%kernel 'list))))

racket/src/cs/main.sps

@@ -818,6 +818,9 @@
       (lambda ()
         (let ([f (dynamic-require mod sym)])
           (f pch)))))
+   (set-destroy-place!
+    (lambda ()
+      (io-place-destroy!)))
 
    (let ([a (or addon-dir
                 (getenv-bytes "PLTADDONDIR"))])

racket/src/cs/rumble.sls

@@ -600,6 +600,7 @@
           unsafe-extflvector-length unsafe-extflvector-ref unsafe-extflvector-set!
 
           set-start-place!           ; not exported to Racket
+          set-destroy-place!         ; not exported to Racket
           fork-place                 ; not exported to Racket
           start-place                ; not exported to Racket
           place-enabled?

racket/src/cs/rumble/place.ss

@@ -91,7 +91,8 @@
                                     (set-box! place-esc-box esc)
                                     (thunk)
                                     0))])
-                     (finish-proc result)))))
+                     (finish-proc result)
+                     (do-destroy-place)))))
   ;; Must be called within an engine, used for memory accounting:
   (define (current-place-roots)
     (list (place-registers)
@@ -105,6 +106,10 @@
 (define (set-start-place! proc)
   (set! do-start-place proc))
 
+(define do-destroy-place void)
+(define (set-destroy-place! proc)
+  (set! do-destroy-place proc))
+
 (define (start-place pch path sym in out err cust plumber)
   (let ([finish (do-start-place pch path sym in out err cust plumber)])
     (reset-async-callback-poll-wakeup!)

racket/src/io/host/rktio.rkt

@@ -10,7 +10,8 @@
          rktio-errno
          rktio-errstep
          racket-error?
-         rktio-place-init!)
+         rktio-place-init!
+         rktio-place-destroy!)
 ;; More `provide`s added by macros below
 
 (define rktio-table
@@ -82,5 +83,9 @@
 (define (rktio-place-init!)
   (set! rktio (rktio_init)))
 
+(define (rktio-place-destroy!)
+  (rktio_destroy rktio)
+  (set! rktio #f))
+
 ;; Only in the main place:
 (void (rktio_do_install_os_signal_handler rktio))

racket/src/io/main.rkt

@@ -25,7 +25,8 @@
          "port/parameter.rkt"
          "path/system.rkt"
          (only-in "host/rktio.rkt"
-                  rktio-place-init!)
+                  rktio-place-init!
+                  rktio-place-destroy!)
          (submod "error/main.rkt"
                  place-init)
          (only-in "sandman/ltps.rkt"
@@ -58,6 +59,7 @@
          (all-from-out "run/main.rkt")
          make-place-ports+fds
          io-place-init!
+         io-place-destroy!
          get-original-error-port)
 
 (define (io-place-init! in-fd out-fd err-fd cust plumber)
@@ -68,3 +70,8 @@
   (install-error-value->string-handler!)
   (init-current-directory!)
   (init-current-ports! in-fd out-fd err-fd cust plumber))
+
+(define (io-place-destroy!)
+  ;; We expect everything based on rktio to be destroyed at this point
+  ;; via custodian shutdown
+  (rktio-place-destroy!))

racket/src/io/port/place.rkt

@@ -17,7 +17,7 @@
         (values #f (dup-fd (fd-port-fd in) void "stdin dup"))
         (reverse-pipe void "stdin pipe")))
   (define (clean-in)
-    (rktio_close child-in-fd)
+    (rktio_close rktio child-in-fd)
     (unless in
       (rktio_close rktio parent-in-fd)))
   (define-values (parent-out-fd child-out-fd)
@@ -25,9 +25,9 @@
         (values #f (dup-fd (fd-port-fd out) clean-in "stdout dup"))
         (pipe clean-in "stdout pipe")))
   (define (clean-out+in)
-    (rktio_close child-out-fd)
+    (rktio_close rktio child-out-fd)
     (unless out
-      (rktio_close parent-out-fd))
+      (rktio_close rktio parent-out-fd))
     (clean-in))
   (define-values (parent-err-fd child-err-fd)
     (if err

racket/src/rktio/rktio_main.c

@@ -72,6 +72,7 @@ void rktio_destroy(rktio_t *rktio)
   rktio_free_ghbn(rktio);
   rktio_free_global_poll_set(rktio);
   rktio_stop_fs_change(rktio);
+  rktio_free_signal(rktio);
 #ifdef RKTIO_SYSTEM_WINDOWS
   rktio_winsock_done(rktio);
 #endif

racket/src/rktio/rktio_poll_set.c

@@ -1127,6 +1127,18 @@ int rktio_initialize_signal(rktio_t *rktio)
 #endif
 }
 
+void rktio_free_signal(rktio_t *rktio)
+{
+#ifdef RKTIO_SYSTEM_UNIX
+  rktio_reliably_close(rktio->external_event_fd);
+  rktio_reliably_close(rktio->put_external_event_fd);
+#endif
+
+#ifdef RKTIO_SYSTEM_WINDOWS
+  CloseHandle(rktio->break_semaphore);
+#endif
+}
+
 rktio_signal_handle_t *rktio_get_signal_handle(rktio_t *rktio)
 {
 #ifdef RKTIO_SYSTEM_UNIX

racket/src/rktio/rktio_private.h

@@ -141,6 +141,7 @@ struct rktio_t {
 void rktio_alloc_global_poll_set(rktio_t *rktio);
 void rktio_free_global_poll_set(rktio_t *rktio);
 int rktio_initialize_signal(rktio_t *rktio);
+void rktio_free_signal(rktio_t *rktio);
 
 #ifdef USE_FAR_RKTIO_FDCALLS