cs: fix stdio/syslog GC logging as triggered by future thread

Always use the main `rktio` instance and don't try to explicitly start
atomic mode.

racket/src/io/logger/main.rkt

@@ -144,7 +144,7 @@
 ;; like `log-level?*`
 (define (log-message* logger level topic message data prefix? in-interrupt?)
   (define msg #f)
-  (when ((logger-max-wanted-level logger) . level>=? . level)
+  (when ((logger-max-wanted-level* logger) . level>=? . level)
     (let loop ([logger logger])
       (for ([r (in-list (logger-receivers logger))])
         (when ((filters-level-for-topic (log-receiver-filters r) topic) . level>=? . level)

racket/src/io/logger/receiver.rkt

@@ -94,11 +94,12 @@
 
 ;; ----------------------------------------
 
-(struct stdio-log-receiver log-receiver (which)
+(struct stdio-log-receiver log-receiver (rktio which)
   #:property
   prop:receiver-send
   (lambda (lr msg)
     ;; called in atomic mode and possibly in host interrupt handler
+    (define rktio (stdio-log-receiver-rktio lr))
     (define fd (rktio_std_fd rktio (stdio-log-receiver-which lr)))
     (define bstr (bytes-append (string->bytes/utf-8 (vector-ref msg 1)) #"\n"))
     (define len (bytes-length bstr))
@@ -113,6 +114,7 @@
 (define (add-stdio-log-receiver! who logger args parse-who which)
   (check who logger? logger)
   (define lr (stdio-log-receiver (parse-filters parse-who args #:default-level 'none)
+                                 rktio
                                  which))
   (atomically
    (add-log-receiver! logger lr #f)
@@ -126,11 +128,12 @@
 
 ;; ----------------------------------------
 
-(struct syslog-log-receiver log-receiver (cmd)
+(struct syslog-log-receiver log-receiver (rktio cmd)
   #:property
   prop:receiver-send
   (lambda (lr msg)
     ;; called in atomic mode and possibly in host interrupt handler
+    (define rktio (syslog-log-receiver-rktio lr))
     (define bstr (bytes-append (string->bytes/utf-8 (vector-ref msg 1)) #"\n"))
     (define pri
       (case (vector-ref msg 0)
@@ -143,6 +146,7 @@
 
 (define/who (add-syslog-log-receiver! logger . args)
   (define lr (syslog-log-receiver (parse-filters 'make-syslog-log-receiver args #:default-level 'none)
+                                  rktio
                                   (path-bytes (find-system-path 'run-file))))
   (atomically
    (add-log-receiver! logger lr #f)

racket/src/io/logger/wanted.rkt

@@ -6,6 +6,7 @@
 
 (provide logger-wanted-level      ; ok to call in host-Scheme interrupt handler
          logger-max-wanted-level
+         logger-max-wanted-level*
          logger-all-levels)
 
 ;; in atomic mode with interrupts disabled
@@ -31,6 +32,10 @@
 
 (define (logger-max-wanted-level logger)
   (atomically/no-interrupts/no-wind
+   (logger-max-wanted-level* logger)))
+
+;; in atomic mode with interrupts disabled
+(define (logger-max-wanted-level* logger)
   (cond
     [((logger-local-level-timestamp logger) . >= . (unbox (logger-root-level-timestamp-box logger)))
      ;; Cached value is up-to-date
@@ -38,7 +43,7 @@
     [else
      ;; Traverse to set cache:
      (update-logger-wanted-level! logger #f)
-      (logger-max-receiver-level logger)])))
+     (logger-max-receiver-level logger)]))
 
 (define (update-logger-wanted-level! logger topic)
   (unless ((logger-local-level-timestamp logger) . >= . (unbox (logger-root-level-timestamp-box logger)))