~drizzle-trunk/drizzle/development

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clean slate
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/* Copyright (C) 2000-2004 MySQL AB
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   This program is free software; you can redistribute it and/or modify
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   it under the terms of the GNU General Public License as published by
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   the Free Software Foundation; version 2 of the License.
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   This program is distributed in the hope that it will be useful,
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   but WITHOUT ANY WARRANTY; without even the implied warranty of
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   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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   GNU General Public License for more details.
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   You should have received a copy of the GNU General Public License
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   along with this program; if not, write to the Free Software
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   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */
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/**
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  @file
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  @details
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  Caching of files with only does (sequential) read or writes of fixed-
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  length records. A read isn't allowed to go over file-length. A read is ok
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  if it ends at file-length and next read can try to read after file-length
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  (and get a EOF-error).
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  Possibly use of asyncronic io.
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  macros for read and writes for faster io.
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  Used instead of FILE when reading or writing whole files.
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  This will make mf_rec_cache obsolete.
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  One can change info->pos_in_file to a higher value to skip bytes in file if
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  also info->rc_pos is set to info->rc_end.
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  If called through open_cached_file(), then the temporary file will
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  only be created if a write exeeds the file buffer or if one calls
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  flush_io_cache().  
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*/
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#include "mysql_priv.h"
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#ifdef HAVE_REPLICATION
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extern "C" {
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/**
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  Read buffered from the net.
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  @retval
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    1   if can't read requested characters
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  @retval
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    0   if record read
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*/
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int _my_b_net_read(register IO_CACHE *info, uchar *Buffer,
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		   size_t Count __attribute__((unused)))
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{
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  ulong read_length;
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  NET *net= &(current_thd)->net;
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  if (!info->end_of_file)
51.1.32 by Jay Pipes
Removed/replaced DBUG symbols and standardized TRUE/FALSE
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    return(1);	/* because my_b_get (no _) takes 1 byte at a time */
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  read_length=my_net_read(net);
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  if (read_length == packet_error)
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  {
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    info->error= -1;
51.1.32 by Jay Pipes
Removed/replaced DBUG symbols and standardized TRUE/FALSE
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    return(1);
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  }
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  if (read_length == 0)
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  {
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    info->end_of_file= 0;			/* End of file from client */
51.1.32 by Jay Pipes
Removed/replaced DBUG symbols and standardized TRUE/FALSE
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    return(1);
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  }
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  /* to set up stuff for my_b_get (no _) */
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  info->read_end = (info->read_pos = (uchar*) net->read_pos) + read_length;
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  Buffer[0] = info->read_pos[0];		/* length is always 1 */
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  /*
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    info->request_pos is used by log_loaded_block() to know the size
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    of the current block.
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    info->pos_in_file is used by log_loaded_block() too.
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  */
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  info->pos_in_file+= read_length;
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  info->request_pos=info->read_pos;
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  info->read_pos++;
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51.1.32 by Jay Pipes
Removed/replaced DBUG symbols and standardized TRUE/FALSE
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  return(0);
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}
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} /* extern "C" */
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#endif /* HAVE_REPLICATION */