From 454a20c8756c9c1d55419153255fc7692b3d2199 Mon Sep 17 00:00:00 2001 From: Florian Weimer Date: Wed, 14 Jun 2023 18:10:08 +0200 Subject: Implement strlcpy and strlcat [BZ #178] These functions are about to be added to POSIX, under Austin Group issue 986. The fortified strlcat implementation does not raise SIGABRT if the destination buffer does not contain a null terminator, it just inherits the non-failing regular strlcat behavior. Reviewed-by: Siddhesh Poyarekar --- string/tst-strlcpy.c | 68 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 68 insertions(+) create mode 100644 string/tst-strlcpy.c (limited to 'string/tst-strlcpy.c') diff --git a/string/tst-strlcpy.c b/string/tst-strlcpy.c new file mode 100644 index 0000000..0063c43 --- /dev/null +++ b/string/tst-strlcpy.c @@ -0,0 +1,68 @@ +/* Test the strlcpy function. + Copyright (C) 2023 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#include +#include +#include +#include + +static int +do_test (void) +{ + struct { + char buf1[16]; + char buf2[16]; + } s; + + /* Nothing is written to the destination if its size is 0. */ + memset (&s, '@', sizeof (s)); + TEST_COMPARE (strlcpy (s.buf1, "Hello!", 0), 6); + TEST_COMPARE_BLOB (&s, sizeof (s), "@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@", 32); + + /* No bytes are are modified in the target buffer if the source + string is short enough. */ + memset (&s, '@', sizeof (s)); + TEST_COMPARE (strlcpy (s.buf1, "Hello!", sizeof (s.buf1)), 6); + TEST_COMPARE_BLOB (&s, sizeof (s), "Hello!\0@@@@@@@@@@@@@@@@@@@@@@@@@", 32); + + /* A source string which fits exactly into the destination buffer is + not truncated. */ + memset (&s, '@', sizeof (s)); + TEST_COMPARE (strlcpy (s.buf1, "Hello, world!!!", sizeof (s.buf1)), 15); + TEST_COMPARE_BLOB (&s, sizeof (s), + "Hello, world!!!\0@@@@@@@@@@@@@@@@@@@@@@@@@", 32); + + /* A source string one character longer than the destination buffer + is truncated by one character. The untruncated source length is + returned. */ + memset (&s, '@', sizeof (s)); + TEST_COMPARE (strlcpy (s.buf1, "Hello, world!!!!", sizeof (s.buf1)), 16); + TEST_COMPARE_BLOB (&s, sizeof (s), + "Hello, world!!!\0@@@@@@@@@@@@@@@@@@@@@@@@@", 32); + + /* An even longer source string is truncated as well, and the + original length is returned. */ + memset (&s, '@', sizeof (s)); + TEST_COMPARE (strlcpy (s.buf1, "Hello, world!!!!!!!!", sizeof (s.buf1)), 20); + TEST_COMPARE_BLOB (&s, sizeof (s), + "Hello, world!!!\0@@@@@@@@@@@@@@@@@@@@@@@@@", 32); + + return 0; +} + +#include -- cgit v1.1