diff options
Diffstat (limited to 'isam/_cache.c')
| -rw-r--r-- | isam/_cache.c | 92 |
1 files changed, 0 insertions, 92 deletions
diff --git a/isam/_cache.c b/isam/_cache.c deleted file mode 100644 index bca9a699a85..00000000000 --- a/isam/_cache.c +++ /dev/null @@ -1,92 +0,0 @@ -/* Copyright (C) 2000 MySQL AB & MySQL Finland AB & TCX DataKonsult AB - - This program is free software; you can redistribute it and/or modify - it under the terms of the GNU General Public License as published by - the Free Software Foundation; either version 2 of the License, or - (at your option) any later version. - - This program 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 General Public License for more details. - - You should have received a copy of the GNU General Public License - along with this program; if not, write to the Free Software - Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ - -/* Functions for read record cacheing with nisam */ -/* Used instead of my_b_read() to allow for no-cacheed seeks */ - -#include "isamdef.h" - -#define READING_NEXT 1 -#define READING_HEADER 2 - - /* Copy block from cache if it`s in it. If re_read_if_possibly is */ - /* set read to cache (if after current file-position) else read to */ - /* buff */ - -int _nisam_read_cache(IO_CACHE *info, byte *buff, ulong pos, uint length, - int flag) -{ - uint read_length,in_buff_length; - ulong offset; - char *in_buff_pos; - - if (pos < info->pos_in_file) - { - read_length= (uint) min((ulong) length,(ulong) (info->pos_in_file-pos)); - info->seek_not_done=1; - VOID(my_seek(info->file,pos,MY_SEEK_SET,MYF(0))); - if (my_read(info->file,buff,read_length,MYF(MY_NABP))) - return 1; - if (!(length-=read_length)) - return 0; - pos+=read_length; - buff+=read_length; - } - if ((offset=pos - (ulong) info->pos_in_file) < - (ulong) (info->read_end - info->request_pos)) - { - in_buff_pos=info->request_pos+(uint) offset; - in_buff_length= min(length,(uint) (info->read_end-in_buff_pos)); - memcpy(buff,info->request_pos+(uint) offset,(size_t) in_buff_length); - if (!(length-=in_buff_length)) - return 0; - pos+=in_buff_length; - buff+=in_buff_length; - } - else - in_buff_length=0; - if (flag & READING_NEXT) - { - if (pos != ((info)->pos_in_file + - (uint) ((info)->read_end - (info)->request_pos))) - { - info->pos_in_file=pos; /* Force start here */ - info->read_pos=info->read_end=info->request_pos; /* Everything used */ - info->seek_not_done=1; - } - else - info->read_pos=info->read_end; /* All block used */ - if (!(*info->read_function)(info,buff,length)) - return 0; - if (!(flag & READING_HEADER) || info->error == -1 || - (uint) info->error+in_buff_length < 3) - return 1; - if (BLOCK_INFO_HEADER_LENGTH < in_buff_length + (uint) info->error) - bzero(buff+info->error,BLOCK_INFO_HEADER_LENGTH - in_buff_length - - (uint) info->error); - return 0; - } - info->seek_not_done=1; - VOID(my_seek(info->file,pos,MY_SEEK_SET,MYF(0))); - if ((read_length=my_read(info->file,buff,length,MYF(0))) == length) - return 0; - if (!(flag & READING_HEADER) || (int) read_length == -1 || - read_length+in_buff_length < 3) - return 1; - bzero(buff+read_length,BLOCK_INFO_HEADER_LENGTH - in_buff_length - - read_length); - return 0; -} /* _nisam_read_cache */ |