From 10ec549991f73c61de2fdad3a2a27c38143931db Mon Sep 17 00:00:00 2001
From: Bryce Kwon <bryce@brycekwon.com>
Date: Fri, 16 Oct 2026 06:10:51 -1000
Subject: Keep the error of a request that dies mid capture

The commit and diff pages collect each file's body before printing it,
and a die in git while one was collected wrote the error page into that
body, which was never sent, so the visitor got a page cut off mid table.
---
 source/html.c             |  1 +
 source/html.h             |  3 ++-
 tests/t0303-robustness.sh | 29 +++++++++++++++++++++++++++++
 3 files changed, 32 insertions(+), 1 deletion(-)

diff --git a/source/html.c b/source/html.c
index caa5a29..ef74bb3 100644
--- a/source/html.c
+++ b/source/html.c
@@ -145,6 +145,7 @@ void html_flush(void)
 void html_discard(void)
 {
 	out_len = 0;
+	capture = NULL;
 }
 
 void html_capture_begin(struct strbuf *sb)
diff --git a/source/html.h b/source/html.h
index 56fcb7f..1960b6a 100644
--- a/source/html.h
+++ b/source/html.h
@@ -27,7 +27,8 @@ extern void html(const char *txt);
 extern void html_flush(void);
 
 /*
- * Drop whatever page output is still buffered. For the die path only.
+ * Drop whatever page output is still buffered and end any capture, so that
+ * what follows reaches stdout. For the die path only.
  */
 extern void html_discard(void);
 
diff --git a/tests/t0303-robustness.sh b/tests/t0303-robustness.sh
index 5cc7507..1963a2e 100755
--- a/tests/t0303-robustness.sh
+++ b/tests/t0303-robustness.sh
@@ -369,6 +369,35 @@ test_expect_success 'a history with a missing parent renders up to the gap' '
 	grep "^Status: 500" tmp
 '
 
+# The commit page collects each file's diff body before printing it, so a
+# die while one is collected has to reach the page rather than the body.
+test_expect_success 'a corrupt blob in a collected diff answers the error' '
+	git init -q corrupt &&
+	(
+		cd corrupt &&
+		test_seq 2000 >f &&
+		git add f &&
+		git commit -q -m one &&
+		test_seq 2000 | sed "s/^5/X/" >f &&
+		git commit -q -a -m two &&
+		blob=$(git rev-parse HEAD:f) &&
+		obj=.git/objects/$(echo $blob | cut -c1-2)/$(echo $blob | cut -c3-) &&
+		size=$(wc -c <$obj) &&
+		chmod u+w $obj &&
+		test_copy_bytes $((size / 2)) <$obj >half &&
+		mv half $obj
+	) &&
+	{
+		echo "virtual-root=/" &&
+		echo "cache-size=0" &&
+		echo "repo.url=corrupt" &&
+		echo "repo.path=$PWD/corrupt/.git"
+	} >corruptrc &&
+	CGIT_CONFIG="$PWD/corruptrc" QUERY_STRING="url=corrupt/commit/" cgit >tmp 2>err &&
+	grep "is corrupt" err &&
+	grep "Unable to complete the request" tmp
+'
+
 test_expect_success 'a filter pipeline sees the default SIGPIPE disposition' '
 	cat >pipe.sh <<-\EOF &&
 	#!/bin/sh
-- 
cgit