aboutsummaryrefslogtreecommitdiff
path: root/string/strlcpy.c
diff options
context:
space:
mode:
Diffstat (limited to 'string/strlcpy.c')
-rw-r--r--string/strlcpy.c46
1 files changed, 46 insertions, 0 deletions
diff --git a/string/strlcpy.c b/string/strlcpy.c
new file mode 100644
index 0000000..7a0df3e
--- /dev/null
+++ b/string/strlcpy.c
@@ -0,0 +1,46 @@
+/* Copy a null-terminated string to a fixed-size buffer, with length checking.
+ 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
+ <https://www.gnu.org/licenses/>. */
+
+#include <string.h>
+
+size_t
+__strlcpy (char *__restrict dest, const char *__restrict src, size_t size)
+{
+ size_t src_length = strlen (src);
+
+ if (__glibc_unlikely (src_length >= size))
+ {
+ if (size > 0)
+ {
+ /* Copy the leading portion of the string. The last
+ character is subsequently overwritten with the NUL
+ terminator, but the destination size is usually a
+ multiple of a small power of two, so writing it twice
+ should be more efficient than copying an odd number of
+ bytes. */
+ memcpy (dest, src, size);
+ dest[size - 1] = '\0';
+ }
+ }
+ else
+ /* Copy the string and its terminating NUL character. */
+ memcpy (dest, src, src_length + 1);
+ return src_length;
+}
+libc_hidden_def (__strlcpy)
+weak_alias (__strlcpy, strlcpy)