git: e4b7b0bcbc74 - main - lib/libc/tests/string: add unit tests for memccpy()

From: Robert Clausecker <fuz_at_FreeBSD.org>
Date: Mon, 25 Dec 2023 14:25:59 UTC
The branch main has been updated by fuz:

URL: https://cgit.FreeBSD.org/src/commit/?id=e4b7b0bcbc741f0998640c2ba55ec00ba613bb75

commit e4b7b0bcbc741f0998640c2ba55ec00ba613bb75
Author:     Robert Clausecker <fuz@FreeBSD.org>
AuthorDate: 2023-12-03 11:42:17 +0000
Commit:     Robert Clausecker <fuz@FreeBSD.org>
CommitDate: 2023-12-25 13:59:40 +0000

    lib/libc/tests/string: add unit tests for memccpy()
    
    Adapted from the strlcpy() unit tests.
    
    Tested by:      developers@, exp-run
    Approved by:    mjg
    MFC after:      1 month
    MFC to:         stable/14
    PR:             275785
---
 lib/libc/tests/string/Makefile       |   1 +
 lib/libc/tests/string/memccpy_test.c | 205 +++++++++++++++++++++++++++++++++++
 2 files changed, 206 insertions(+)

diff --git a/lib/libc/tests/string/Makefile b/lib/libc/tests/string/Makefile
index 81e59ee65155..a6e8eb18075a 100644
--- a/lib/libc/tests/string/Makefile
+++ b/lib/libc/tests/string/Makefile
@@ -9,6 +9,7 @@ ATF_TESTS_C+=		ffsll_test
 ATF_TESTS_C+=		fls_test
 ATF_TESTS_C+=		flsl_test
 ATF_TESTS_C+=		flsll_test
+ATF_TESTS_C+=		memccpy_test
 ATF_TESTS_C+=		memcmp_test
 ATF_TESTS_C+=		memset_s_test
 ATF_TESTS_C+=		strncmp_test
diff --git a/lib/libc/tests/string/memccpy_test.c b/lib/libc/tests/string/memccpy_test.c
new file mode 100644
index 000000000000..82f4ef34af54
--- /dev/null
+++ b/lib/libc/tests/string/memccpy_test.c
@@ -0,0 +1,205 @@
+/*-
+ * Copyright (c) 2009 David Schultz <das@FreeBSD.org>
+ * Copyright (c) 2023 The FreeBSD Foundation
+ * All rights reserved.
+ *
+ * Portions of this software were developed by Robert Clausecker
+ * <fuz@FreeBSD.org> under sponsorship from the FreeBSD Foundation.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+#include <sys/param.h>
+#include <sys/mman.h>
+#include <assert.h>
+#include <dlfcn.h>
+#include <limits.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <atf-c.h>
+
+void *(*memccpy_fn)(void *restrict, const void *restrict, int, size_t);
+
+static char *
+makebuf(size_t len, int guard_at_end)
+{
+	char *buf;
+	size_t alloc_size, page_size;
+
+	page_size = getpagesize();
+	alloc_size = roundup2(len, page_size) + page_size;
+
+	buf = mmap(NULL, alloc_size, PROT_READ | PROT_WRITE, MAP_ANON, -1, 0);
+	assert(buf);
+	if (guard_at_end) {
+		assert(munmap(buf + alloc_size - page_size, page_size) == 0);
+		return (buf + alloc_size - page_size - len);
+	} else {
+		assert(munmap(buf, page_size) == 0);
+		return (buf + page_size);
+	}
+}
+
+static void
+test_memccpy(const char *s)
+{
+	char *src, *dst, *expected;
+	size_t size, bufsize, x;
+	int i, j;
+
+	size = strlen(s) + 1;
+	for (i = 0; i <= 1; i++) {
+		for (j = 0; j <= 1; j++) {
+			for (bufsize = 0; bufsize <= size + 10; bufsize++) {
+				src = makebuf(size, i);
+				memcpy(src, s, size);
+				dst = makebuf(bufsize, j);
+				memset(dst, 'X', bufsize);
+				expected = bufsize >= size ? dst + size : NULL;
+				assert(memccpy_fn(dst, src, src[size-1], bufsize) == expected);
+				assert(bufsize == 0 || strncmp(src, dst, bufsize - 1) == 0);
+				for (x = size; x < bufsize; x++)
+					assert(dst[x] == 'X');
+			}
+		}
+	}
+}
+
+static void
+test_sentinel(char *dest, char *src, size_t destlen, size_t srclen)
+{
+	size_t i, effective_len;
+	void *res, *wantres;
+	const char *fail = NULL;
+	char terminator;
+
+	for (i = 0; i < srclen; i++)
+		/* src will never include (){} */
+		src[i] = '0' + i;
+
+	/* source sentinels: not to be copied */
+	src[-1] = '(';
+	src[srclen] = ')';
+
+	memset(dest, '\xee', destlen);
+
+	/* destination sentinels: not to be touched */
+	dest[-1] = '{';
+	dest[destlen] = '}';
+
+	effective_len = srclen < destlen ? srclen : destlen;
+	wantres = srclen <= destlen ? dest + srclen : NULL;
+	terminator = src[srclen-1];
+	res = memccpy_fn(dest, src, terminator, destlen);
+
+	if (dest[-1] != '{')
+		fail = "start sentinel overwritten";
+	else if (dest[destlen] != '}')
+		fail = "end sentinel overwritten";
+	else if (res != wantres)
+		fail = "incorrect return value";
+	else if (destlen > 0 && memcmp(src, dest, effective_len) != 0)
+		fail = "string not copied correctly";
+	else for (i = srclen; i < destlen; i++)
+		if (dest[i] != '\xee') {
+			fail = "buffer mutilated behind string";
+			break;
+		}
+
+	if (fail)
+		atf_tc_fail_nonfatal("%s\n"
+		    "memccpy(%p \"%s\", %p \"%s\", %u '%c', %zu) = %p (want %p)\n",
+		    fail, dest, dest, src, src, terminator, terminator, destlen, res, wantres);
+}
+
+ATF_TC_WITHOUT_HEAD(null);
+ATF_TC_BODY(null, tc)
+{
+	ATF_CHECK_EQ(memccpy_fn(NULL, "foo", 42, 0), NULL);
+}
+
+ATF_TC(zero_extension);
+ATF_TC_HEAD(zero_extension, tc)
+{
+	atf_tc_set_md_var(tc, "descr",
+	    "Ensure the upper bits of the terminator are ignored");
+}
+ATF_TC_BODY(zero_extension, tc)
+{
+	int mask = -1 & ~UCHAR_MAX;
+	char buf[16];
+
+	memset(buf, 0xcc, sizeof(buf));
+	ATF_CHECK_EQ(memccpy(buf, "foobar", 'r', sizeof(buf)), buf + sizeof("foobar") - 1);
+	ATF_CHECK_EQ(memcmp(buf, "foobar", sizeof("foobar") - 1), 0);
+
+	memset(buf, 0xcc, sizeof(buf));
+	ATF_CHECK_EQ(memccpy(buf, "foobar", mask | 'r', sizeof(buf)), buf + sizeof("foobar") - 1);
+	ATF_CHECK_EQ(memcmp(buf, "foobar", sizeof("foobar") - 1), 0);
+}
+
+ATF_TC_WITHOUT_HEAD(bounds);
+ATF_TC_BODY(bounds, tc)
+{
+	size_t i;
+	char buf[64];
+
+	for (i = 0; i < sizeof(buf) - 1; i++) {
+		buf[i] = ' ' + i;
+		test_memccpy(buf);
+	}
+}
+
+ATF_TC_WITHOUT_HEAD(alignments);
+ATF_TC_BODY(alignments, tc)
+{
+	size_t srcalign, destalign, srclen, destlen;
+	char src[15+2+64]; /* 15 offsets + 64 max length + sentinels */
+	char dest[15+2+64]; /* 15 offsets + 64 max length + sentinels */
+
+	for (srcalign = 0; srcalign < 16; srcalign++)
+		for (destalign = 0; destalign < 16; destalign++)
+			for (srclen = 1; srclen < 64; srclen++)
+				for (destlen = 0; destlen < 64; destlen++)
+					test_sentinel(dest+destalign+1,
+					    src+srcalign+1, destlen, srclen);
+}
+
+ATF_TP_ADD_TCS(tp)
+{
+	void *dl_handle;
+
+	dl_handle = dlopen(NULL, RTLD_LAZY);
+	memccpy_fn = dlsym(dl_handle, "test_memccpy");
+	if (memccpy_fn == NULL)
+		memccpy_fn = memccpy;
+
+	ATF_TP_ADD_TC(tp, null);
+	ATF_TP_ADD_TC(tp, zero_extension);
+	ATF_TP_ADD_TC(tp, bounds);
+	ATF_TP_ADD_TC(tp, alignments);
+
+	return (atf_no_error());
+}