diff --git a/lib/libdiff/tests/libdiff_test.c b/lib/libdiff/tests/libdiff_test.c
index f12717686721..e82a36f3d38a 100644
--- a/lib/libdiff/tests/libdiff_test.c
+++ b/lib/libdiff/tests/libdiff_test.c
@@ -1,61 +1,62 @@
 /*-
  * Copyright (c) 2024 Klara, Inc.
  *
  * SPDX-License-Identifier: BSD-2-Clause
  */
 
 #include <sys/types.h>
 #include <sys/mman.h>
 
 #include <assert.h>
 #include <errno.h>
+#include <stdint.h>
 #include <stdio.h>
 #include <string.h>
 #include <unistd.h>
 
 #include <arraylist.h>
 #include <diff_main.h>
 
 #include <atf-c.h>
 
 ATF_TC_WITH_CLEANUP(diff_atomize_truncated);
 ATF_TC_HEAD(diff_atomize_truncated, tc)
 {
 	atf_tc_set_md_var(tc, "descr", "Verify that the atomizer "
 	    "does not crash when an input file is truncated");
 }
 ATF_TC_BODY(diff_atomize_truncated, tc)
 {
 	char line[128];
 	struct diff_config cfg = { .atomize_func = diff_atomize_text_by_line };
 	struct diff_data d = { };
 	const char *fn = atf_tc_get_ident(tc);
 	FILE *f;
 	unsigned char *p;
 	size_t size = 65536;
 
 	ATF_REQUIRE((f = fopen(fn, "w+")) != NULL);
 	line[sizeof(line) - 1] = '\n';
 	for (unsigned int i = 0; i <= size / sizeof(line); i++) {
 		memset(line, 'a' + i % 26, sizeof(line) - 1);
 		ATF_REQUIRE(fwrite(line, sizeof(line), 1, f) == 1);
 	}
 	ATF_REQUIRE(fsync(fileno(f)) == 0);
 	rewind(f);
 	ATF_REQUIRE(truncate(fn, size / 2) == 0);
 	ATF_REQUIRE((p = mmap(NULL, size, PROT_READ, MAP_PRIVATE, fileno(f), 0)) != MAP_FAILED);
 	ATF_REQUIRE(diff_atomize_file(&d, &cfg, f, p, size, 0) == 0);
 	ATF_REQUIRE((size_t)d.len <= size / 2);
 	ATF_REQUIRE((size_t)d.len >= size / 2 - sizeof(line));
 	ATF_REQUIRE(d.atomizer_flags & DIFF_ATOMIZER_FILE_TRUNCATED);
 }
 ATF_TC_CLEANUP(diff_atomize_truncated, tc)
 {
 	unlink(atf_tc_get_ident(tc));
 }
 
 ATF_TP_ADD_TCS(tp)
 {
 	ATF_TP_ADD_TC(tp, diff_atomize_truncated);
 	return atf_no_error();
 }
diff --git a/usr.bin/diff/tests/diff_test.sh b/usr.bin/diff/tests/diff_test.sh
index 9a17d180da02..ab731fa32d26 100755
--- a/usr.bin/diff/tests/diff_test.sh
+++ b/usr.bin/diff/tests/diff_test.sh
@@ -1,394 +1,393 @@
 
 atf_test_case simple
 atf_test_case unified
 atf_test_case header
 atf_test_case header_ns
 atf_test_case ifdef
 atf_test_case group_format
 atf_test_case side_by_side
 atf_test_case side_by_side_tabbed
 atf_test_case brief_format
 atf_test_case b230049
 atf_test_case stripcr_o
 atf_test_case b252515
 atf_test_case b278988
 atf_test_case Bflag
 atf_test_case Nflag
 atf_test_case tabsize
 atf_test_case conflicting_format
 atf_test_case label
 atf_test_case report_identical
 atf_test_case non_regular_file
 atf_test_case binary
 atf_test_case functionname
 atf_test_case noderef
 atf_test_case ignorecase
 
 simple_body()
 {
 	atf_check -o file:$(atf_get_srcdir)/simple.out -s eq:1 \
 		diff "$(atf_get_srcdir)/input1.in" "$(atf_get_srcdir)/input2.in"
 
 	atf_check -o file:$(atf_get_srcdir)/simple_e.out -s eq:1 \
 		diff -e "$(atf_get_srcdir)/input1.in" "$(atf_get_srcdir)/input2.in"
 
 	atf_check -o file:$(atf_get_srcdir)/simple_u.out -s eq:1 \
 		diff -u -L input1 -L input2 "$(atf_get_srcdir)/input1.in" "$(atf_get_srcdir)/input2.in"
 
 	atf_check -o file:$(atf_get_srcdir)/simple_n.out -s eq:1 \
 		diff -n "$(atf_get_srcdir)/input1.in" "$(atf_get_srcdir)/input2.in"
 
 	atf_check -o inline:"Files $(atf_get_srcdir)/input1.in and $(atf_get_srcdir)/input2.in differ\n" -s eq:1 \
 		diff -q "$(atf_get_srcdir)/input1.in" "$(atf_get_srcdir)/input2.in"
 
 	atf_check \
 		diff -q "$(atf_get_srcdir)/input1.in" "$(atf_get_srcdir)/input1.in"
 
 	atf_check -o file:$(atf_get_srcdir)/simple_i.out -s eq:1 \
 		diff -i "$(atf_get_srcdir)/input_c1.in" "$(atf_get_srcdir)/input_c2.in"
 
 	atf_check -o file:$(atf_get_srcdir)/simple_w.out -s eq:1 \
 		diff -w "$(atf_get_srcdir)/input_c1.in" "$(atf_get_srcdir)/input_c2.in"
 
 	atf_check -o file:$(atf_get_srcdir)/simple_b.out -s eq:1 \
 		diff -b "$(atf_get_srcdir)/input_c1.in" "$(atf_get_srcdir)/input_c2.in"
 
 	atf_check -o file:$(atf_get_srcdir)/simple_p.out -s eq:1 \
 		diff --label input_c1.in --label input_c2.in -p "$(atf_get_srcdir)/input_c1.in" "$(atf_get_srcdir)/input_c2.in"
 }
 
 unified_body()
 {
 	atf_check -o file:$(atf_get_srcdir)/unified_p.out -s eq:1 \
 		diff -up -L input_c1.in -L input_c2.in  "$(atf_get_srcdir)/input_c1.in" "$(atf_get_srcdir)/input_c2.in"
 	atf_check -o file:$(atf_get_srcdir)/unified_9999.out -s eq:1 \
 		diff -u9999 -L input_c1.in -L input_c2.in "$(atf_get_srcdir)/input_c1.in" "$(atf_get_srcdir)/input_c2.in"
 }
 
 b230049_body()
 {
 	printf 'a\nb\r\nc\n' > b230049_a.in
 	printf 'a\r\nb\r\nc\r\n' > b230049_b.in
 	atf_check -o empty -s eq:0 \
 		diff -up --strip-trailing-cr -L b230049_a.in -L b230049_b.in \
 		    b230049_a.in b230049_b.in
 }
 
 stripcr_o_body()
 {
 	printf 'a\nX\nc\n' > stripcr_o_X.in
 	printf 'a\r\nY\r\nc\r\n' > stripcr_o_Y.in
 	atf_check -o "file:$(atf_get_srcdir)/strip_o.out" -s eq:1 \
 		diff -L1 -L2 -u --strip-trailing-cr stripcr_o_X.in stripcr_o_Y.in
 }
 
 b252515_body()
 {
 	printf 'a b\n' > b252515_a.in
 	printf 'a  b\n' > b252515_b.in
 	atf_check -o empty -s eq:0 \
 		diff -qw b252515_a.in b252515_b.in
 }
 
 b278988_body()
 {
 	printf 'a\nb\nn' > b278988.a.in
 	printf 'a\n\nb\nn' > b278988.b.in
 	atf_check -o empty -s eq:0 \
 		diff -Bw b278988.a.in b278988.b.in
-
 }
 
 header_body()
 {
 	export TZ=UTC
 	: > empty
 	echo hello > hello
 	touch -d 2015-04-03T01:02:03 empty
 	touch -d 2016-12-22T11:22:33 hello
 	atf_check -o "file:$(atf_get_srcdir)/header.out" -s eq:1 \
 		diff -u empty hello
 }
 
 header_ns_body()
 {
 	export TZ=UTC
 	: > empty
 	echo hello > hello
 	touch -d 2015-04-03T01:02:03.123456789 empty
 	touch -d 2016-12-22T11:22:33.987654321 hello
 	atf_check -o "file:$(atf_get_srcdir)/header_ns.out" -s eq:1 \
 		diff -u empty hello
 }
 
 ifdef_body()
 {
 	atf_check -o file:$(atf_get_srcdir)/ifdef.out -s eq:1 \
 		diff -D PLOP "$(atf_get_srcdir)/input_c1.in" \
 		"$(atf_get_srcdir)/input_c2.in"
 }
 
 group_format_body()
 {
 	atf_check -o file:$(atf_get_srcdir)/group-format.out -s eq:1 \
 		diff --changed-group-format='<<<<<<< (local)
 %<=======
 %>>>>>>>> (stock)
 ' "$(atf_get_srcdir)/input_c1.in" "$(atf_get_srcdir)/input_c2.in"
 }
 
 side_by_side_body()
 {
 	atf_check -o save:A printf "A\nB\nC\n"
 	atf_check -o save:B printf "D\nB\nE\n"
 
 	exp_output=$(printf "A[[:space:]]+|[[:space:]]+D\nB[[:space:]]+B\nC[[:space:]]+|[[:space:]]+E")
 	exp_output_suppressed=$(printf "A[[:space:]]+|[[:space:]]+D\nC[[:space:]]+|[[:space:]]+E")
 
 	atf_check -o match:"$exp_output" -s exit:1 \
 	    diff --side-by-side A B
 	atf_check -o match:"$exp_output" -s exit:1 \
 	    diff -y A B
 	atf_check -o match:"$exp_output_suppressed" -s exit:1 \
 	    diff -y --suppress-common-lines A B
 	atf_check -o match:"$exp_output_suppressed" -s exit:1 \
 	    diff -W 65 -y --suppress-common-lines A B
 }
 
 side_by_side_tabbed_body()
 {
 	file_a=$(atf_get_srcdir)/side_by_side_tabbed_a.in
 	file_b=$(atf_get_srcdir)/side_by_side_tabbed_b.in
 
 	atf_check -o save:diffout -s not-exit:0 \
 	    diff -y ${file_a} ${file_b}
 	atf_check -o save:diffout_expanded -s not-exit:0 \
 	    diff -yt ${file_a} ${file_b}
 
 	atf_check -o not-empty grep -Ee 'file A.+file B' diffout
 	atf_check -o not-empty grep -Ee 'file A.+file B' diffout_expanded
 
 	atf_check -o not-empty grep -Ee 'tabs.+tabs' diffout
 	atf_check -o not-empty grep -Ee 'tabs.+tabs' diffout_expanded
 }
 
 brief_format_body()
 {
 	atf_check mkdir A B
 
 	atf_check -x "echo 1 > A/test-file"
 	atf_check -x "echo 2 > B/test-file"
 
 	atf_check cp -Rf A C
 	atf_check cp -Rf A D
 
 	atf_check -x "echo 3 > D/another-test-file"
 
 	atf_check \
 	    -s exit:1 \
 	    -o inline:"Files A/test-file and B/test-file differ\n" \
 	    diff -rq A B
 
 	atf_check diff -rq A C
 
 	atf_check \
 	    -s exit:1 \
 	    -o inline:"Only in D: another-test-file\n" \
 	    diff -rq A D
 
 	atf_check \
 	    -s exit:1 \
 	    -o inline:"Files A/another-test-file and D/another-test-file differ\n" \
 	    diff -Nrq A D
 }
 
 Bflag_body()
 {
 	atf_check -x 'printf "A\nB\n" > A'
 	atf_check -x 'printf "A\n\nB\n" > B'
 	atf_check -x 'printf "A\n \nB\n" > C'
 	atf_check -x 'printf "A\nC\nB\n" > D'
 	atf_check -x 'printf "A\nB\nC\nD\nE\nF\nG\nH" > E'
 	atf_check -x 'printf "A\n\nB\nC\nD\nE\nF\nX\nH" > F'
 
 	atf_check -s exit:0 -o inline:"" diff -B A B
 	atf_check -s exit:1 -o file:"$(atf_get_srcdir)/Bflag_C.out" diff -B A C
 	atf_check -s exit:1 -o file:"$(atf_get_srcdir)/Bflag_D.out" diff -B A D
 	atf_check -s exit:1 -o file:"$(atf_get_srcdir)/Bflag_F.out" diff -B E F
 }
 
 Nflag_body()
 {
 	atf_check -x 'printf "foo" > A'
 
 	atf_check -s exit:1 -o ignore -e ignore diff -N A NOFILE 
 	atf_check -s exit:1 -o ignore -e ignore diff -N NOFILE A 
 	atf_check -s exit:2 -o ignore -e ignore diff -N NOFILE1 NOFILE2 
 }
 
 tabsize_body()
 {
 	printf "\tA\n" > A
 	printf "\tB\n" > B
 
 	atf_check -s exit:1 \
 	    -o inline:"1c1\n<  A\n---\n>  B\n" \
 	    diff -t --tabsize 1 A B
 }
 
 conflicting_format_body()
 {
 	printf "\tA\n" > A
 	printf "\tB\n" > B
 
 	atf_check -s exit:2 -e ignore diff -c -u A B
 	atf_check -s exit:2 -e ignore diff -e -f A B
 	atf_check -s exit:2 -e ignore diff -y -q A B
 	atf_check -s exit:2 -e ignore diff -q -u A B
 	atf_check -s exit:2 -e ignore diff -q -c A B
 	atf_check -s exit:2 -e ignore diff --normal -c A B
 	atf_check -s exit:2 -e ignore diff -c --normal A B
 
 	atf_check -s exit:1 -o ignore -e ignore diff -u -u A B
 	atf_check -s exit:1 -o ignore -e ignore diff -e -e A B
 	atf_check -s exit:1 -o ignore -e ignore diff -y -y A B
 	atf_check -s exit:1 -o ignore -e ignore diff -q -q A B
 	atf_check -s exit:1 -o ignore -e ignore diff -c -c A B
 	atf_check -s exit:1 -o ignore -e ignore diff --normal --normal A B
 }
 
 label_body()
 {
 	printf "\tA\n" > A
 
 	atf_check -o inline:"Files hello and world are identical\n" \
 		-s exit:0 diff --label hello --label world -s A A
 
 	atf_check -o inline:"Binary files hello and world differ\n" \
 		-s exit:1 diff --label hello --label world `which diff` `which ls`
 }
 
 report_identical_head()
 {
 	atf_set "require.user" unprivileged
 }
 report_identical_body()
 {
 	printf "\tA\n" > A
 	printf "\tB\n" > B
 	atf_check -s exit:0 -o match:"are identical" \
 		  diff -s A A
 	atf_check -s exit:1 -o not-match:"are identical" \
 		  diff -s A B
 	chmod -r B
 	atf_check -s exit:2 -e inline:"diff: B: Permission denied\n" \
 		-o empty diff -s A B
 }
 
 non_regular_file_body()
 {
 	printf "\tA\n" > A
 	mkfifo B
 	printf "\tA\n" > B &
 
 	atf_check diff A B
 	printf "\tB\n" > B &
 	atf_check -s exit:1 \
 		-o inline:"--- A\n+++ B\n@@ -1 +1 @@\n-\tA\n+\tB\n" \
 		diff --label A --label B -u A B
 }
 
 binary_body()
 {
 	# the NUL byte has to be after at least BUFSIZ bytes to trick asciifile()
 	yes 012345678901234567890123456789012345678901234567890 | head -n 174 > A
 	cp A B
 	printf '\n\0\n' >> A
 	printf '\nx\n' >> B
 
 	atf_check -o inline:"Binary files A and B differ\n" -s exit:1 diff A B
 	atf_check -o inline:"176c\nx\n.\n" -s exit:1 diff -ae A B
 }
 
 functionname_body()
 {
 	atf_check -o file:$(atf_get_srcdir)/functionname_c.out -s exit:1 \
 		diff -u -p -L functionname.in -L functionname_c.in \
 		"$(atf_get_srcdir)/functionname.in" "$(atf_get_srcdir)/functionname_c.in"
 
 	atf_check -o file:$(atf_get_srcdir)/functionname_objcm.out -s exit:1 \
 		diff -u -p -L functionname.in -L functionname_objcm.in \
 		"$(atf_get_srcdir)/functionname.in" "$(atf_get_srcdir)/functionname_objcm.in"
 
 	atf_check -o file:$(atf_get_srcdir)/functionname_objcclassm.out -s exit:1 \
 		diff -u -p -L functionname.in -L functionname_objcclassm.in \
 		"$(atf_get_srcdir)/functionname.in" "$(atf_get_srcdir)/functionname_objcclassm.in"
 }
 
 noderef_body()
 {
 	atf_check mkdir A B
 
 	atf_check -x "echo 1 > A/test-file"
 	atf_check -x "echo 1 > test-file"
 	atf_check -x "echo 1 > test-file2"
 
 	atf_check ln -s $(pwd)/test-file B/test-file
 
 	atf_check -o empty -s exit:0 diff -r A B
 	atf_check -o inline:"File A/test-file is a file while file B/test-file is a symbolic link\n" \
 		-s exit:1 diff -r --no-dereference A B
 
 	# both test files are now the same symbolic link
 	atf_check rm A/test-file
 
 	atf_check ln -s $(pwd)/test-file A/test-file
 	atf_check -o empty -s exit:0 diff -r A B
 	atf_check -o empty -s exit:0 diff -r --no-dereference A B
 
 	# make test files different symbolic links, but same contents
 	atf_check unlink A/test-file
 	atf_check ln -s $(pwd)/test-file2 A/test-file
 
 	atf_check -o empty -s exit:0 diff -r A B
 	atf_check -o inline:"Symbolic links A/test-file and B/test-file differ\n" -s exit:1 diff -r --no-dereference A B
 }
 
 ignorecase_body()
 {
 	atf_check mkdir A
 	atf_check mkdir B
 
 	atf_check -x "echo hello > A/foo"
 	atf_check -x "echo hello > B/FOO"
 
 	atf_check -o empty -s exit:0 diff -u -r --ignore-file-name-case A B
 }
 
 atf_init_test_cases()
 {
 	atf_add_test_case simple
 	atf_add_test_case unified
 	atf_add_test_case header
 	atf_add_test_case header_ns
 	atf_add_test_case ifdef
 	atf_add_test_case group_format
 	atf_add_test_case side_by_side
 	atf_add_test_case side_by_side_tabbed
 	atf_add_test_case brief_format
 	atf_add_test_case b230049
 	atf_add_test_case stripcr_o
 	atf_add_test_case b252515
 	atf_add_test_case b278988
 	atf_add_test_case Bflag
 	atf_add_test_case Nflag
 	atf_add_test_case tabsize
 	atf_add_test_case conflicting_format
 	atf_add_test_case label
 	atf_add_test_case report_identical
 	atf_add_test_case non_regular_file
 	atf_add_test_case binary
 	atf_add_test_case functionname
 	atf_add_test_case noderef
 	atf_add_test_case ignorecase
 }