| lh | 9ed821d | 2023-04-07 01:36:19 -0700 | [diff] [blame^] | 1 | /* Copyright (C) 1995-2015 Free Software Foundation, Inc. |
| 2 | This file is part of the GNU C Library. |
| 3 | Contributed by Ulrich Drepper <drepper@gnu.ai.mit.edu>, 1995. |
| 4 | |
| 5 | The GNU C Library is free software; you can redistribute it and/or |
| 6 | modify it under the terms of the GNU Lesser General Public |
| 7 | License as published by the Free Software Foundation; either |
| 8 | version 2.1 of the License, or (at your option) any later version. |
| 9 | |
| 10 | The GNU C Library is distributed in the hope that it will be useful, |
| 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 13 | Lesser General Public License for more details. |
| 14 | |
| 15 | You should have received a copy of the GNU Lesser General Public |
| 16 | License along with the GNU C Library; if not, see |
| 17 | <http://www.gnu.org/licenses/>. */ |
| 18 | |
| 19 | #include <wchar.h> |
| 20 | |
| 21 | |
| 22 | /* Append no more than N wide-character of SRC onto DEST. */ |
| 23 | wchar_t * |
| 24 | __wcsncat_chk (wchar_t *dest, const wchar_t *src, size_t n, size_t destlen) |
| 25 | { |
| 26 | wchar_t c; |
| 27 | wchar_t * const s = dest; |
| 28 | |
| 29 | /* Find the end of DEST. */ |
| 30 | do |
| 31 | { |
| 32 | if (__glibc_unlikely (destlen-- == 0)) |
| 33 | __chk_fail (); |
| 34 | c = *dest++; |
| 35 | } |
| 36 | while (c != L'\0'); |
| 37 | |
| 38 | /* Make DEST point before next character, so we can increment |
| 39 | it while memory is read (wins on pipelined cpus). */ |
| 40 | ++destlen; |
| 41 | dest -= 2; |
| 42 | |
| 43 | if (n >= 4) |
| 44 | { |
| 45 | size_t n4 = n >> 2; |
| 46 | do |
| 47 | { |
| 48 | if (__glibc_unlikely (destlen-- == 0)) |
| 49 | __chk_fail (); |
| 50 | c = *src++; |
| 51 | *++dest = c; |
| 52 | if (c == L'\0') |
| 53 | return s; |
| 54 | if (__glibc_unlikely (destlen-- == 0)) |
| 55 | __chk_fail (); |
| 56 | c = *src++; |
| 57 | *++dest = c; |
| 58 | if (c == L'\0') |
| 59 | return s; |
| 60 | if (__glibc_unlikely (destlen-- == 0)) |
| 61 | __chk_fail (); |
| 62 | c = *src++; |
| 63 | *++dest = c; |
| 64 | if (c == L'\0') |
| 65 | return s; |
| 66 | if (__glibc_unlikely (destlen-- == 0)) |
| 67 | __chk_fail (); |
| 68 | c = *src++; |
| 69 | *++dest = c; |
| 70 | if (c == L'\0') |
| 71 | return s; |
| 72 | } while (--n4 > 0); |
| 73 | n &= 3; |
| 74 | } |
| 75 | |
| 76 | while (n > 0) |
| 77 | { |
| 78 | if (__glibc_unlikely (destlen-- == 0)) |
| 79 | __chk_fail (); |
| 80 | c = *src++; |
| 81 | *++dest = c; |
| 82 | if (c == L'\0') |
| 83 | return s; |
| 84 | n--; |
| 85 | } |
| 86 | |
| 87 | if (c != L'\0') |
| 88 | { |
| 89 | if (__glibc_unlikely (destlen-- == 0)) |
| 90 | __chk_fail (); |
| 91 | *++dest = L'\0'; |
| 92 | } |
| 93 | |
| 94 | return s; |
| 95 | } |