| /* Copy memory to memory until the specified number of bytes |
| has been copied with error checking. Overlap is handled correctly. |
| Copyright (C) 1991,1995,1996,1997,2003,2004 Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| Contributed by Torbjorn Granlund (tege@sics.se). |
| |
| 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, write to the Free |
| Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA |
| 02111-1307 USA. */ |
| |
| #include <string.h> |
| #include <memcopy.h> |
| #include <pagecopy.h> |
| |
| #ifndef MEMMOVE_CHK |
| # define MEMMOVE_CHK __memmove_chk |
| #endif |
| |
| void * |
| MEMMOVE_CHK (dest, src, len, destlen) |
| void *dest; |
| const void *src; |
| size_t len; |
| size_t destlen; |
| { |
| if (__builtin_expect (destlen < len, 0)) |
| __chk_fail (); |
| |
| unsigned long int dstp = (long int) dest; |
| unsigned long int srcp = (long int) src; |
| |
| /* This test makes the forward copying code be used whenever possible. |
| Reduces the working set. */ |
| if (dstp - srcp >= len) /* *Unsigned* compare! */ |
| { |
| /* Copy from the beginning to the end. */ |
| |
| /* If there not too few bytes to copy, use word copy. */ |
| if (len >= OP_T_THRES) |
| { |
| /* Copy just a few bytes to make DSTP aligned. */ |
| len -= (-dstp) % OPSIZ; |
| BYTE_COPY_FWD (dstp, srcp, (-dstp) % OPSIZ); |
| |
| /* Copy whole pages from SRCP to DSTP by virtual address |
| manipulation, as much as possible. */ |
| |
| PAGE_COPY_FWD_MAYBE (dstp, srcp, len, len); |
| |
| /* Copy from SRCP to DSTP taking advantage of the known |
| alignment of DSTP. Number of bytes remaining is put |
| in the third argument, i.e. in LEN. This number may |
| vary from machine to machine. */ |
| |
| WORD_COPY_FWD (dstp, srcp, len, len); |
| |
| /* Fall out and copy the tail. */ |
| } |
| |
| /* There are just a few bytes to copy. Use byte memory operations. */ |
| BYTE_COPY_FWD (dstp, srcp, len); |
| } |
| else |
| { |
| /* Copy from the end to the beginning. */ |
| srcp += len; |
| dstp += len; |
| |
| /* If there not too few bytes to copy, use word copy. */ |
| if (len >= OP_T_THRES) |
| { |
| /* Copy just a few bytes to make DSTP aligned. */ |
| len -= dstp % OPSIZ; |
| BYTE_COPY_BWD (dstp, srcp, dstp % OPSIZ); |
| |
| /* Copy from SRCP to DSTP taking advantage of the known |
| alignment of DSTP. Number of bytes remaining is put |
| in the third argument, i.e. in LEN. This number may |
| vary from machine to machine. */ |
| |
| WORD_COPY_BWD (dstp, srcp, len, len); |
| |
| /* Fall out and copy the tail. */ |
| } |
| |
| /* There are just a few bytes to copy. Use byte memory operations. */ |
| BYTE_COPY_BWD (dstp, srcp, len); |
| } |
| |
| return dest; |
| } |