Commit dc3a192ae841706bb965218c68b0085bbec2b35e | zig

author	Andrew Kelley <andrew@ziglang.org> 2024-05-27 10:29:39-07:00
committer	Andrew Kelley <andrew@ziglang.org> 2024-05-27 20:56:48-07:00
log	dc3a192ae841706bb965218c68b0085bbec2b35e
tree	24aa6cca1ca96e9ceeedc528942c55ab372fcc5a
parent	6145819c0ba00924b37bab78200aeab6306c1672

std.Progress: count newlines more accurately

Split newline_count into written_newline_count and
accumulated_newline_count. This handle the case when the tryLock() fails
to obtain the lock, because in such case there would not be any newlines
written to the terminal but the system would incorrectly think there
were. Now, written_newline_count is only adjusted when the write() call
succeeds.

Furthermore, write() call failure is handled by exiting the update
thread.

1 files changed, 21 insertions(+), 16 deletions(-)

lib
- std
  - Progress.zig

lib/std/Progress.zig+21-16

...	...	@@ -32,9 +32,11 @@ initial_delay_ns: u64,
32	32
33	33	rows: u16,
34	34	cols: u16,
35		/// Needed because terminal escape codes require one to take scrolling into
36		/// account.
37		newline_count: u16,
	35	/// Tracks the number of newlines that have been actually written to the terminal.
	36	written_newline_count: u16,
	37	/// Tracks the number of newlines that will be written to the terminal if the
	38	/// draw buffer is sent.
	39	accumulated_newline_count: u16,
38	40
39	41	/// Accessed only by the update thread.
40	42	draw_buffer: []u8,
...	...	@@ -284,7 +286,8 @@ var global_progress: Progress = .{
284	286	.initial_delay_ns = undefined,
285	287	.rows = 0,
286	288	.cols = 0,
287		.newline_count = 0,
	289	.written_newline_count = 0,
	290	.accumulated_newline_count = 0,
288	291	.draw_buffer = undefined,
289	292	.done = false,
290	293
...	...	@@ -423,7 +426,7 @@ fn updateThreadRun() void {
423	426	const buffer = computeRedraw(&serialized_buffer);
424	427	if (stderr_mutex.tryLock()) {
425	428	defer stderr_mutex.unlock();
426		write(buffer);
	429	write(buffer) catch return;
427	430	}
428	431	}
429	432
...	...	@@ -440,7 +443,7 @@ fn updateThreadRun() void {
440	443	const buffer = computeRedraw(&serialized_buffer);
441	444	if (stderr_mutex.tryLock()) {
442	445	defer stderr_mutex.unlock();
443		write(buffer);
	446	write(buffer) catch return;
444	447	}
445	448	}
446	449	}
...	...	@@ -499,7 +502,7 @@ const tree_line = "\x1B\x28\x30\x78\x1B\x28\x42 "; // │
499	502	const tree_langle = "\x1B\x28\x30\x6d\x71\x1B\x28\x42 "; // └─
500	503
501	504	fn clearTerminal() void {
502		if (global_progress.newline_count == 0) return;
	505	if (global_progress.written_newline_count == 0) return;
503	506
504	507	var i: usize = 0;
505	508	const buf = global_progress.draw_buffer;
...	...	@@ -512,15 +515,17 @@ fn clearTerminal() void {
512	515	buf[i..][0..finish_sync.len].* = finish_sync.*;
513	516	i += finish_sync.len;
514	517
515		write(buf[0..i]);
	518	global_progress.accumulated_newline_count = 0;
	519	write(buf[0..i]) catch {
	520	global_progress.terminal = null;
	521	};
516	522	}
517	523
518	524	fn computeClear(buf: []u8, start_i: usize) usize {
519	525	var i = start_i;
520	526
521		const prev_nl_n = global_progress.newline_count;
	527	const prev_nl_n = global_progress.written_newline_count;
522	528	if (prev_nl_n > 0) {
523		global_progress.newline_count = 0;
524	529	buf[i] = '\r';
525	530	i += 1;
526	531	for (0..prev_nl_n) \|_\| {
...	...	@@ -854,6 +859,7 @@ fn computeRedraw(serialized_buffer: *Serialized.Buffer) []u8 {
854	859
855	860	i = computeClear(buf, i);
856	861
	862	global_progress.accumulated_newline_count = 0;
857	863	const root_node_index: Node.Index = @enumFromInt(0);
858	864	i = computeNode(buf, i, serialized, children, root_node_index);
859	865
...	...	@@ -937,7 +943,7 @@ fn computeNode(
937	943	i = @min(global_progress.cols + start_i, i);
938	944	buf[i] = '\n';
939	945	i += 1;
940		global_progress.newline_count += 1;
	946	global_progress.accumulated_newline_count += 1;
941	947	}
942	948
943	949	if (global_progress.withinRowLimit()) {
...	...	@@ -959,14 +965,13 @@ fn withinRowLimit(p: *Progress) bool {
959	965	// The +2 here is so that the PS1 is not scrolled off the top of the terminal.
960	966	// one because we keep the cursor on the next line
961	967	// one more to account for the PS1
962		return p.newline_count + 2 < p.rows;
	968	return p.accumulated_newline_count + 2 < p.rows;
963	969	}
964	970
965		fn write(buf: []const u8) void {
	971	fn write(buf: []const u8) anyerror!void {
966	972	const tty = global_progress.terminal orelse return;
967		tty.writeAll(buf) catch {
968		global_progress.terminal = null;
969		};
	973	try tty.writeAll(buf);
	974	global_progress.written_newline_count = global_progress.accumulated_newline_count;
970	975	}
971	976
972	977	fn writeIpc(fd: posix.fd_t, serialized: Serialized) error{BrokenPipe}!void {