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by brian
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/* Copyright (C) 2003 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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243.1.14
by Jay Pipes
* Ensured all drizzled/field/x.cc files to include mysql_priv.h |
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#include <drizzled/common_includes.h> |
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by brian
clean slate |
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#include "transparent_file.h" |
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Transparent_file::Transparent_file() : lower_bound(0), buff_size(IO_SIZE) |
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{
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481
by Brian Aker
Remove all of uchar. |
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buff= (unsigned char *) my_malloc(buff_size*sizeof(unsigned char), MYF(MY_WME)); |
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by brian
clean slate |
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}
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Transparent_file::~Transparent_file() |
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{
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481
by Brian Aker
Remove all of uchar. |
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free((unsigned char*)buff); |
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by brian
clean slate |
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}
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void Transparent_file::init_buff(File filedes_arg) |
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{
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filedes= filedes_arg; |
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/* read the beginning of the file */
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lower_bound= 0; |
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398.1.10
by Monty Taylor
Actually removed VOID() this time. |
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my_seek(filedes, 0, MY_SEEK_SET, MYF(0)); |
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by brian
clean slate |
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if (filedes && buff) |
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upper_bound= my_read(filedes, buff, buff_size, MYF(0)); |
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}
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481
by Brian Aker
Remove all of uchar. |
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unsigned char *Transparent_file::ptr() |
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by brian
clean slate |
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{
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return buff; |
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}
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off_t Transparent_file::start() |
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{
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return lower_bound; |
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}
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off_t Transparent_file::end() |
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{
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return upper_bound; |
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}
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off_t Transparent_file::read_next() |
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{
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size_t bytes_read; |
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/*
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No need to seek here, as the file managed by Transparent_file class
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always points to upper_bound byte
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*/
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if ((bytes_read= my_read(filedes, buff, buff_size, MYF(0))) == MY_FILE_ERROR) |
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return (off_t) -1; |
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/* end of file */
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if (!bytes_read) |
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return (off_t) -1; |
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lower_bound= upper_bound; |
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upper_bound+= bytes_read; |
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return lower_bound; |
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}
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char Transparent_file::get_value(off_t offset) |
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{
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size_t bytes_read; |
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/* check boundaries */
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if ((lower_bound <= offset) && (offset < upper_bound)) |
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return buff[offset - lower_bound]; |
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398.1.10
by Monty Taylor
Actually removed VOID() this time. |
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my_seek(filedes, offset, MY_SEEK_SET, MYF(0)); |
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by brian
clean slate |
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/* read appropriate portion of the file */
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if ((bytes_read= my_read(filedes, buff, buff_size, |
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MYF(0))) == MY_FILE_ERROR) |
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return 0; |
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lower_bound= offset; |
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upper_bound= lower_bound + bytes_read; |
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/* end of file */
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if (upper_bound == offset) |
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return 0; |
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return buff[0]; |
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}
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