/* Copyright (C) 1993-2013 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 <http://www.gnu.org/licenses/>. */ /* This is almost copied from strncpy.c, written by Torbjorn Granlund. */ #include <string.h> /* Copy no more than N characters of SRC to DEST, returning the address of the terminating '\0' in DEST, if any, or else DEST + N. */ char * __stpncpy_chk (char *dest, const char *src, size_t n, size_t destlen) { char c; char *s = dest; if (__builtin_expect (destlen < n, 0)) __chk_fail (); if (n >= 4) { size_t n4 = n >> 2; for (;;) { c = *src++; *dest++ = c; if (c == '\0') break; c = *src++; *dest++ = c; if (c == '\0') break; c = *src++; *dest++ = c; if (c == '\0') break; c = *src++; *dest++ = c; if (c == '\0') break; if (--n4 == 0) goto last_chars; } n -= dest - s; goto zero_fill; } last_chars: n &= 3; if (n == 0) return dest; for (;;) { c = *src++; --n; *dest++ = c; if (c == '\0') break; if (n == 0) return dest; } zero_fill: while (n-- > 0) dest[n] = '\0'; return dest - 1; }