/* Copy a null-terminated string to a fixed-size buffer, with length checking. Copyright (C) 2023-2024 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 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)