os: add support for signal handling on JS backend (#12818)

vlib/os/os_js.js.v

@@ -136,3 +136,7 @@ pub fn getuid() int {
 pub fn execvp(cmd string, args []string) ? {
 	panic('os.execvp() is not available on JS backend')
 }
+
+pub fn stdin_resume() {
+	#$process.stdin.resume();
+}

vlib/os/process.js.v

@@ -94,6 +94,10 @@ pub fn (mut p Process) stdin_write(s string) {
 	#p.val.pid.stdin.write(s)
 }
 
+pub fn (mut p Process) stdin_resume() {
+	#p.val.pid.stdin.resume()
+}
+
 // todo(playX): probably does not work
 
 // will read from stdout pipe, will only return when EOF (end of file) or data

vlib/os/signal.c.v

@@ -2,48 +2,6 @@ module os
 
 #include <signal.h>
 
-// os.Signal - enumerate possible POSIX signals and
-// their integer codes.
-// NB: the integer codes are given here explicitly,
-// to make it easier to lookup, without needing to
-// consult man pages / signal.h .
-
-pub enum Signal {
-	hup = 1
-	int = 2
-	quit = 3
-	ill = 4
-	trap = 5
-	abrt = 6
-	bus = 7
-	fpe = 8
-	kill = 9
-	usr1 = 10
-	segv = 11
-	usr2 = 12
-	pipe = 13
-	alrm = 14
-	term = 15
-	stkflt = 16
-	chld = 17
-	cont = 18
-	stop = 19
-	tstp = 20
-	ttin = 21
-	ttou = 22
-	urg = 23
-	xcpu = 24
-	xfsz = 25
-	vtalrm = 26
-	prof = 27
-	winch = 28
-	poll = 29
-	pwr = 30
-	sys = 31
-}
-
-type SignalHandler = fn (Signal)
-
 fn C.signal(signal int, handlercb SignalHandler) voidptr
 
 // signal will assign `handler` callback to be called when `signum` signal is received.

vlib/os/signal.js.v

@@ -0,0 +1,133 @@
+module os
+
+fn signal_str(signal Signal) string {
+	mut result := signal.str().to_upper()
+	result = 'SIG$result'
+	return result
+}
+
+fn signal_from_str(str JS.String) Signal {
+	s := string(str)
+	return match s {
+		'SIGHUP' {
+			Signal.hup
+		}
+		'SIGINT' {
+			Signal.int
+		}
+		'SIGQUIT' {
+			Signal.quit
+		}
+		'SIGILL' {
+			Signal.ill
+		}
+		'SIGTRAP' {
+			Signal.trap
+		}
+		'SIGABRT' {
+			Signal.abrt
+		}
+		'SIGBUS' {
+			Signal.bus
+		}
+		'SIGFPE' {
+			Signal.fpe
+		}
+		'SIGKILL' {
+			Signal.kill
+		}
+		'SIGUSR1' {
+			Signal.usr1
+		}
+		'SIGSEGV' {
+			Signal.segv
+		}
+		'SIGUSR2' {
+			Signal.usr2
+		}
+		'SIGPIPE' {
+			Signal.pipe
+		}
+		'SIGALRM' {
+			Signal.alrm
+		}
+		'SIGTERM' {
+			Signal.term
+		}
+		'SIGSTKFLT' {
+			Signal.stkflt
+		}
+		'SIGCHLD' {
+			Signal.chld
+		}
+		'SIGCONT' {
+			Signal.cont
+		}
+		'SIGSTOP' {
+			Signal.stop
+		}
+		'SIGTSTP' {
+			Signal.tstp
+		}
+		'SIGTTIN' {
+			Signal.ttin
+		}
+		'SIGTTOU' {
+			Signal.ttou
+		}
+		'SIGURG' {
+			Signal.urg
+		}
+		'SIGXCPU' {
+			Signal.xcpu
+		}
+		'SIGXFSZ' {
+			Signal.xfsz
+		}
+		'SIGVTALRM' {
+			Signal.vtalrm
+		}
+		'SIGPROF' {
+			Signal.prof
+		}
+		'SIGWINCH' {
+			Signal.winch
+		}
+		'SIGPOLL' {
+			Signal.poll
+		}
+		'SIGPWR' {
+			Signal.pwr
+		}
+		'SIGSYS' {
+			Signal.sys
+		}
+		else {
+			panic('unknown signal: $s')
+		}
+	}
+}
+
+// signal will assign `handler` callback to be called when `signum` signal is received.
+//
+// # Behaviour on different backends:
+// - NodeJS: Will use `process.on` and add `handler` to the listeners list for `signum` to happen
+// - Browser: Will use `window.addEventListener` for handling signal
+//
+// TODO: Add signal events implementation for browser backend
+pub fn signal_opt(signum Signal, handler SignalHandler) ?SignalHandler {
+	signame := signal_str(signum)
+	_ := signame
+	$if js_node {
+		#$process.on(signame.str,function (sig) { handler(os__signal_from_str(sig));});
+
+		return handler
+	} $else $if js_browser {
+		#let event = new CustomEvent(signame.str, {detail: signum});
+		#window.addEventListener(signame.str, function (e) { handler(e.detail); });
+
+		return handler
+	} $else {
+		return error('signal handlers are not supported on bare JS')
+	}
+}

vlib/os/signal.v

@@ -0,0 +1,43 @@
+module os
+
+// os.Signal - enumerate possible POSIX signals and
+// their integer codes.
+// NB: the integer codes are given here explicitly,
+// to make it easier to lookup, without needing to
+// consult man pages / signal.h .
+
+pub enum Signal {
+	hup = 1
+	int = 2
+	quit = 3
+	ill = 4
+	trap = 5
+	abrt = 6
+	bus = 7
+	fpe = 8
+	kill = 9
+	usr1 = 10
+	segv = 11
+	usr2 = 12
+	pipe = 13
+	alrm = 14
+	term = 15
+	stkflt = 16
+	chld = 17
+	cont = 18
+	stop = 19
+	tstp = 20
+	ttin = 21
+	ttou = 22
+	urg = 23
+	xcpu = 24
+	xfsz = 25
+	vtalrm = 26
+	prof = 27
+	winch = 28
+	poll = 29
+	pwr = 30
+	sys = 31
+}
+
+type SignalHandler = fn (Signal)