[PATCH v4 1/7] lib/hexdump.c: Fix selftests

From: Alastair D'Silva
Date: Mon Jun 24 2019 - 23:19:52 EST


From: Alastair D'Silva <alastair@xxxxxxxxxxx>

The overflow tests did not account for the situation where no
overflow occurs and len < rowsize.

This patch renames the cryptic variables and accounts for the
above case.

The selftests now pass.

Signed-off-by: Alastair D'Silva <alastair@xxxxxxxxxxx>
---
lib/test_hexdump.c | 48 +++++++++++++++++++++++++++-------------------
1 file changed, 28 insertions(+), 20 deletions(-)

diff --git a/lib/test_hexdump.c b/lib/test_hexdump.c
index 5144899d3c6b..bef97a964582 100644
--- a/lib/test_hexdump.c
+++ b/lib/test_hexdump.c
@@ -163,45 +163,53 @@ static void __init test_hexdump_overflow(size_t buflen, size_t len,
{
char test[TEST_HEXDUMP_BUF_SIZE];
char buf[TEST_HEXDUMP_BUF_SIZE];
- int rs = rowsize, gs = groupsize;
- int ae, he, e, f, r;
- bool a;
+ int ascii_len, hex_len, expected_len, fill_point, ngroups, rc;
+ bool match;

total_tests++;

memset(buf, FILL_CHAR, sizeof(buf));

- r = hex_dump_to_buffer(data_b, len, rs, gs, buf, buflen, ascii);
+ rc = hex_dump_to_buffer(data_b, len, rowsize, groupsize, buf, buflen,
+ ascii);

/*
* Caller must provide the data length multiple of groupsize. The
* calculations below are made with that assumption in mind.
*/
- ae = rs * 2 /* hex */ + rs / gs /* spaces */ + 1 /* space */ + len /* ascii */;
- he = (gs * 2 /* hex */ + 1 /* space */) * len / gs - 1 /* no trailing space */;
+ ngroups = rowsize / groupsize;
+ hex_len = (groupsize * 2 /* hex */ + 1 /* spaces */) * ngroups
+ - 1 /* no trailing space */;
+ ascii_len = hex_len + 2 /* space */ + len /* ascii */;
+
+ if (len < rowsize) {
+ ngroups = len / groupsize;
+ hex_len = (groupsize * 2 /* hex */ + 1 /* spaces */) * ngroups
+ - 1 /* no trailing space */;
+ }

- if (ascii)
- e = ae;
- else
- e = he;
+ expected_len = (ascii) ? ascii_len : hex_len;

- f = min_t(int, e + 1, buflen);
+ fill_point = min_t(int, expected_len + 1, buflen);
if (buflen) {
- test_hexdump_prepare_test(len, rs, gs, test, sizeof(test), ascii);
- test[f - 1] = '\0';
+ test_hexdump_prepare_test(len, rowsize, groupsize, test,
+ sizeof(test), ascii);
+ test[fill_point - 1] = '\0';
}
- memset(test + f, FILL_CHAR, sizeof(test) - f);
+ memset(test + fill_point, FILL_CHAR, sizeof(test) - fill_point);

- a = r == e && !memcmp(test, buf, TEST_HEXDUMP_BUF_SIZE);
+ match = rc == expected_len && !memcmp(test, buf, TEST_HEXDUMP_BUF_SIZE);

buf[sizeof(buf) - 1] = '\0';

- if (!a) {
- pr_err("Len: %zu buflen: %zu strlen: %zu\n",
- len, buflen, strnlen(buf, sizeof(buf)));
- pr_err("Result: %d '%s'\n", r, buf);
- pr_err("Expect: %d '%s'\n", e, test);
+ if (!match) {
+ pr_err("rowsize: %u groupsize: %u ascii: %d Len: %zu buflen: %zu strlen: %zu\n",
+ rowsize, groupsize, ascii, len, buflen,
+ strnlen(buf, sizeof(buf)));
+ pr_err("Result: %d '%-.*s'\n", rc, (int)buflen, buf);
+ pr_err("Expect: %d '%-.*s'\n", expected_len, (int)buflen, test);
failed_tests++;
+
}
}

--
2.21.0