mzte-mpv: clear line before logging

lib/common-zig/src/main.zig

@@ -1,7 +1,15 @@
 const std = @import("std");
+const root = @import("root");
 
 pub usingnamespace @import("delimited_writer.zig");
 
+pub const Opts = struct {
+    log_pfx: ?[]const u8 = null,
+    log_clear_line: bool = false,
+};
+
+const opts: Opts = if (@hasDecl(root, "mztecommon_opts")) root.mztecommon_opts else .{};
+
 var stderr_isatty: ?bool = null;
 
 pub var log_file: ?std.fs.File = null;
@@ -12,11 +20,6 @@ pub fn logFn(
     comptime fmt: []const u8,
     args: anytype,
 ) void {
-    const log_pfx: ?[]const u8 = if (@hasDecl(@import("root"), "mztecommon_log_pfx"))
-        @import("root").mztecommon_log_pfx
-    else
-        null;
-
     const color = log_file == null and stderr_isatty orelse blk: {
         const isatty = std.posix.isatty(std.posix.STDERR_FILENO);
         stderr_isatty = isatty;
@@ -25,7 +28,11 @@ pub fn logFn(
 
     const logfile = log_file orelse std.io.getStdErr();
 
-    const scope_prefix = if (log_pfx) |lpfx|
+    if (opts.log_clear_line) {
+        logfile.writer().writeAll("\x1b[2K\r") catch {};
+    }
+
+    const scope_prefix = if (opts.log_pfx) |lpfx|
         if (scope != .default)
             "[" ++ lpfx ++ " " ++ @tagName(scope) ++ "] "
         else

plugins/mzte-mpv/src/main.zig

@@ -1,4 +1,5 @@
 const std = @import("std");
+const common = @import("common");
 const c = ffi.c;
 
 const ffi = @import("ffi.zig");
@@ -6,10 +7,13 @@ const util = @import("util.zig");
 
 pub const std_options = std.Options{
     .log_level = .debug,
-    .logFn = @import("common").logFn,
+    .logFn = common.logFn,
 };
 
-pub const mztecommon_log_pfx = "mzte-mpv";
+pub const mztecommon_opts = common.Opts{
+    .log_pfx = "mzte-mpv",
+    .log_clear_line = true,
+};
 
 export fn mpv_open_cplugin(handle: *c.mpv_handle) callconv(.C) c_int {
     tryMain(handle) catch |e| {

scripts/mzteriver/src/main.zig

@@ -1,4 +1,5 @@
 const std = @import("std");
+const common = @import("common");
 const opts = @import("opts");
 
 const init = @import("init.zig").init;
@@ -11,7 +12,9 @@ pub const std_options = std.Options{
     .logFn = @import("common").logFn,
 };
 
-pub const mztecommon_log_pfx = "mzteriver";
+pub const mztecommon_opts = common.Opts{
+    .log_pfx = "mzteriver",
+};
 
 pub fn main() !void {
     var dbg_gpa = if (@import("builtin").mode == .Debug) std.heap.GeneralPurposeAllocator(.{}){} else {};