From: Matt Corallo <git@bluematt.me>
Date: Wed, 14 Jul 2021 13:55:48 +0000 (+0000)
Subject: Write to stdout all at once to reduce "flashing" on remote monitoring
X-Git-Url: http://git.bitcoin.ninja/index.cgi?p=dnsseed-rust;a=commitdiff_plain;h=a0b4b6586954733f299d2825d4e82549ef901ad6

Write to stdout all at once to reduce "flashing" on remote monitoring
---

diff --git a/src/printer.rs b/src/printer.rs
index d9cf375..7c938fa 100644
--- a/src/printer.rs
+++ b/src/printer.rs
@@ -44,8 +44,7 @@ impl Printer {
 			loop {
 				std::thread::sleep(std::time::Duration::from_secs(1));
 
-				let stdout = std::io::stdout();
-				let mut out = stdout.lock();
+				let mut out = Vec::new();
 
 				{
 					let stats = thread_arc.lock().unwrap();
@@ -53,70 +52,73 @@ impl Printer {
 						break;
 					}
 
-					out.write_all(b"\x1b[2J\x1b[;H\n").expect("stdout broken?");
+					out.write_all(b"\x1b[2J\x1b[;H\n").unwrap();
 					for line in stats.lines.iter() {
-						out.write_all(line.as_bytes()).expect("stdout broken?");
-						out.write_all(b"\n").expect("stdout broken?");
+						out.write_all(line.as_bytes()).unwrap();
+						out.write_all(b"\n").unwrap();
 					}
 
-					out.write_all(b"\nNode counts by status:\n").expect("stdout broken?");
+					out.write_all(b"\nNode counts by status:\n").unwrap();
 					for i in 0..AddressState::get_count() {
 						out.write_all(format!("{:22}: {}\n", AddressState::from_num(i).unwrap().to_str(),
 								store.get_node_count(AddressState::from_num(i).unwrap())
-								).as_bytes()).expect("stdout broken?");
+								).as_bytes()).unwrap();
 					}
 					let generations = store.get_bloom_node_count();
-					out.write_all(b"Bloom filter generations contain:").expect("stdout broken?");
+					out.write_all(b"Bloom filter generations contain:").unwrap();
 					for generation in &generations {
-						out.write_all(format!(" {}", generation).as_bytes()).expect("stdout broken?");
+						out.write_all(format!(" {}", generation).as_bytes()).unwrap();
 					}
 
 					out.write_all(format!(
-							"\n\nCurrent connections open/in progress: {}\n", stats.connection_count).as_bytes()).expect("stdout broken?");
+							"\n\nCurrent connections open/in progress: {}\n", stats.connection_count).as_bytes()).unwrap();
 					out.write_all(format!(
-							"Current block count: {}\n", stats.header_count).as_bytes()).expect("stdout broken?");
+							"Current block count: {}\n", stats.header_count).as_bytes()).unwrap();
 
 					out.write_all(format!(
 							"Timeout for full run (in seconds): {} (\"t x\" to change to x seconds)\n", store.get_u64(U64Setting::RunTimeout)
-							).as_bytes()).expect("stdout broken?");
+							).as_bytes()).unwrap();
 					out.write_all(format!(
 							"Minimum protocol version: {} (\"v x\" to change value to x)\n", store.get_u64(U64Setting::MinProtocolVersion)
-							).as_bytes()).expect("stdout broken?");
+							).as_bytes()).unwrap();
 					out.write_all(format!(
 							"Subversion match regex: {} (\"s x\" to change value to x)\n", store.get_regex(RegexSetting::SubverRegex).as_str()
-							).as_bytes()).expect("stdout broken?");
+							).as_bytes()).unwrap();
 
-					out.write_all(b"\nRetry times (in seconds):\n").expect("stdout broken?");
+					out.write_all(b"\nRetry times (in seconds):\n").unwrap();
 					for i in 0..AddressState::get_count() {
 						let scan_secs = store.get_u64(U64Setting::RescanInterval(AddressState::from_num(i).unwrap()));
 						out.write_all(format!(
 								"{:22} ({:2}): {:5} (ie {} hrs, {} min)\n", AddressState::from_num(i).unwrap().to_str(), i,
 								scan_secs, scan_secs / 60 / 60, (scan_secs / 60) % 60,
-								).as_bytes()).expect("stdout broken?");
+								).as_bytes()).unwrap();
 					}
 
 					out.write_all(format!(
 							"\nBGP Routing Table: {} v4 nets, {} v6 nets, {} max paths\n",
-							stats.v4_table_size, stats.v6_table_size, stats.paths).as_bytes()).expect("stdout broken?");
+							stats.v4_table_size, stats.v6_table_size, stats.paths).as_bytes()).unwrap();
 
-					out.write_all(b"\nCommands:\n").expect("stdout broken?");
-					out.write_all(b"q: quit\n").expect("stdout broken?");
+					out.write_all(b"\nCommands:\n").unwrap();
+					out.write_all(b"q: quit\n").unwrap();
 					out.write_all(format!(
 							"r x y: Change retry time for status x (int value, see retry times section for name mappings) to y (in seconds)\n"
-							).as_bytes()).expect("stdout broken?");
+							).as_bytes()).unwrap();
 					out.write_all(format!(
 							"w x: Change the amount of time a node is considered WAS_GOOD after it fails to x from {} (in seconds)\n",
 							store.get_u64(U64Setting::WasGoodTimeout)
-							).as_bytes()).expect("stdout broken?");
-					out.write_all(b"a x: Scan node x\n").expect("stdout broken?");
-					out.write_all(b"b x: BGP Lookup IP x\n").expect("stdout broken?");
-					out.write_all(b"\x1b[s").expect("stdout broken?"); // Save cursor position and provide a blank line before cursor
-					out.write_all(b"\x1b[;H\x1b[2K").expect("stdout broken?");
-					out.write_all(b"Most recent log:\n").expect("stdout broken?");
-					out.write_all(b"\x1b[u").expect("stdout broken?"); // Restore cursor position and go up one line
+							).as_bytes()).unwrap();
+					out.write_all(b"a x: Scan node x\n").unwrap();
+					out.write_all(b"b x: BGP Lookup IP x\n").unwrap();
+					out.write_all(b"\x1b[s").unwrap(); // Save cursor position and provide a blank line before cursor
+					out.write_all(b"\x1b[;H\x1b[2K").unwrap();
+					out.write_all(b"Most recent log:\n").unwrap();
+					out.write_all(b"\x1b[u").unwrap(); // Restore cursor position and go up one line
 				}
 
-				out.flush().expect("stdout broken?");
+				let stdout = std::io::stdout();
+				let mut stdout_lock = stdout.lock();
+				stdout_lock.write_all(&out).expect("stdout broken?");
+				stdout_lock.flush().expect("stdout broken?");
 			}
 		});
 		Printer {