56 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			V
		
	
	
			
		
		
	
	
			56 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			V
		
	
	
module net
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const (
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	crlf     = '\r\n'
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	msg_peek = 0x02
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	max_read = 400
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)
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// read_line is a *simple*, *non customizable*, blocking line reader.
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// It will *always* return a line, ending with CRLF, or just '', on EOF.
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// NB: if you want more control over the buffer, please use a buffered IO
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// reader instead: `io.new_buffered_reader(reader: con)`
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pub fn (mut con TcpConn) read_line() string {
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	mut buf := [net.max_read]byte{} // where C.recv will store the network data
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	mut res := '' // The final result, including the ending \n.
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	for {
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		mut line := '' // The current line. Can be a partial without \n in it.
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		n := C.recv(con.sock.handle, &buf[0], net.max_read - 1, net.msg_peek | msg_nosignal)
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		if n == -1 {
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			return res
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		}
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		if n == 0 {
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			return res
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		}
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		buf[n] = `\0`
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		mut eol_idx := -1
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		for i in 0 .. n {
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			if int(buf[i]) == `\n` {
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				eol_idx = i
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				// Ensure that tos_clone(buf) later,
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				// will return *only* the first line (including \n),
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				// and ignore the rest
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				buf[i + 1] = `\0`
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				break
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			}
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		}
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		line = unsafe { tos_clone(&buf[0]) }
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		if eol_idx > 0 {
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			// At this point, we are sure that recv returned valid data,
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			// that contains *at least* one line.
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			// Ensure that the block till the first \n (including it)
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			// is removed from the socket's receive queue, so that it does
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			// not get read again.
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			C.recv(con.sock.handle, &buf[0], eol_idx + 1, msg_nosignal)
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			res += line
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			break
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		}
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		// recv returned a buffer without \n in it .
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		C.recv(con.sock.handle, &buf[0], n, msg_nosignal)
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		res += line
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		res += net.crlf
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		break
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	}
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	return res
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}
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