83 lines
2.4 KiB
Plaintext
83 lines
2.4 KiB
Plaintext
## operating system signal routing
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fun chk(ok msg) {
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if ok { printf "OK: %s\n" msg } \
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else { printf "ERROR: %s\n" msg }
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}
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## --- SIGPIPE must not be fatal ---
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## with the default disposition, writing to a pipe whose reader has gone kills
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## the process outright and no I/O primitive can ever report the condition.
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p := (sys.pipe)
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r := (core.basicAt p 0)
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w := (core.basicAt p 1)
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sys.close r
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raised := false
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try {
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sys.write w (core.basicNew ByteArray 4)
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} catch (e) {
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raised := true
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}
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chk raised "writing to a pipe with no reader raises instead of killing the VM"
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sys.close w
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## the VM is genuinely still usable afterwards, not merely still alive
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q := (sys.pipe)
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chk (= (sys.write (core.basicAt q 1) (core.basicNew ByteArray 2)) 2) "I/O still works after SIGPIPE"
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sys.close (core.basicAt q 0)
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sys.close (core.basicAt q 1)
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## --- catch and uncatch are idempotent ---
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chk (= (sys.sig-catch sys.SIGUSR1) sys.SIGUSR1) "sys.sig-catch returns the signal number"
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chk (= (sys.sig-catch sys.SIGUSR1) sys.SIGUSR1) "catching an already caught signal is fine"
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chk (= (sys.sig-uncatch sys.SIGUSR1) sys.SIGUSR1) "sys.sig-uncatch returns the signal number"
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chk (= (sys.sig-uncatch sys.SIGUSR1) sys.SIGUSR1) "uncatching an uncaught signal is fine"
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## --- a real signal reaches hak code, without stalling the coprocesses ---
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## SIGCHLD is used because a child exiting is something this test can arrange
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## on its own, with no outside help.
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sys.sig-catch sys.SIGCHLD
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h := (sys.sig-getfd)
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s := (core.sem-new)
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tmo := (core.sem-new)
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sg := (core.semgr-new)
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core.semgr-add sg s
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core.semgr-add sg tmo
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fin := (core.sem-new)
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ticks := 0
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signo := -1
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pr := (sys.popen "sleep 1; exit 4" "r")
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proc := (core.basicAt pr 0)
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fun waiter() {
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core.sem-signal tmo 20 0
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core.sem-signal-on-input s h
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w := (core.semgr-wait sg)
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core.sem-unsignal s
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core.sem-unsignal tmo
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if (eqv? w tmo) { signo := -2 } \
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else { signo := (sys.sig-get) }
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core.sem-signal fin
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return 0
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}
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fun ticker() {
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## the waiter is parked on the signal descriptor by now
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while (< ticks 4) {
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ticks := (+ ticks 1)
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core.yield
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}
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}
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core.fork waiter
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core.fork ticker
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core.sem-wait fin
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chk (= ticks 4) "coprocesses ran while a coprocess waited on a signal"
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chk (= signo sys.SIGCHLD) "the signal number came through the signal descriptor"
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chk (= (sys.pwait proc) 4) "and the child's exit status is readable"
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sys.pclose proc
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sys.sig-uncatch sys.SIGCHLD
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