From b3da216f1b36b76d8591e64ad1f51079b81bfa8e Mon Sep 17 00:00:00 2001
From: Andrew Kelley <andrew@ziglang.org>
Date: Thu, 1 May 2025 19:20:42 -0700
Subject: [PATCH] std.io.BufferedReader: add readRemaining

---
 lib/std/io/BufferedReader.zig | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/lib/std/io/BufferedReader.zig b/lib/std/io/BufferedReader.zig
index 2b8624351b..23f45e93b3 100644
--- a/lib/std/io/BufferedReader.zig
+++ b/lib/std/io/BufferedReader.zig
@@ -90,6 +90,20 @@ pub fn readAll(br: *BufferedReader, bw: *BufferedWriter, limit: Reader.Limit) Re
     }
 }
 
+/// "Pump" data from the reader to the writer, handling `error.EndOfStream` as
+/// a success case.
+///
+/// Returns total number of bytes written to `bw`.
+pub fn readRemaining(br: *BufferedReader, bw: *BufferedWriter) Reader.RwRemainingError!usize {
+    var offset: usize = 0;
+    while (true) {
+        offset += br.read(bw, .unlimited) catch |err| switch (err) {
+            error.EndOfStream => return offset,
+            else => |e| return e,
+        };
+    }
+}
+
 /// Equivalent to `readVec` but reads at most `limit` bytes.
 pub fn readVecLimit(br: *BufferedReader, data: []const []u8, limit: Reader.Limit) Reader.Error!usize {
     _ = br;