Subject: [PATCH 2/3] sideband: avoid short write(2)

From: Junio C Hamano <[email-masked]>
Date: Sat, 2 Mar 2024 11:03:47 -0800

The sideband demultiplexor writes the data it receives on sideband
with xwrite().  We can lose data if the underlying write(2) results
in a short write.

If they are limited to unimportant bytes like eye-candy progress
meter, it may be OK to lose them, but lets be careful and ensure
that we use write_in_full() instead.  Note that the original does
not check for errors, and this rewrite does not check for one.  At
least not yet.

Signed-off-by: Junio C Hamano <[email-masked]>
---
 sideband.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/sideband.c b/sideband.c
index 266a67342b..5d8907151f 100644
--- a/sideband.c
+++ b/sideband.c
@@ -220,7 +220,7 @@ int demultiplex_sideband(const char *me, int status,
 			}
 
 			strbuf_addch(scratch, *brk);
-			xwrite(2, scratch->buf, scratch->len);
+			write_in_full(2, scratch->buf, scratch->len);
 			strbuf_reset(scratch);
 
 			b = brk + 1;
@@ -247,7 +247,7 @@ int demultiplex_sideband(const char *me, int status,
 		die("%s", scratch->buf);
 	if (scratch->len) {
 		strbuf_addch(scratch, '\n');
-		xwrite(2, scratch->buf, scratch->len);
+		write_in_full(2, scratch->buf, scratch->len);
 	}
 	strbuf_release(scratch);
 	return 1;
-- 
2.44.0-84-gb387623c12