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-rw-r--r--isam/_locking.c345
1 files changed, 0 insertions, 345 deletions
diff --git a/isam/_locking.c b/isam/_locking.c
deleted file mode 100644
index e19804549e5..00000000000
--- a/isam/_locking.c
+++ /dev/null
@@ -1,345 +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 */
-
-/*
- locking of isam-tables.
- reads info from a isam-table. Must be first request before doing any furter
- calls to any isamfunktion. Is used to allow many process use the same
- isamdatabase.
- */
-
-#include "isamdef.h"
-#ifdef __WIN__
-#include <errno.h>
-#endif
-
- /* lock table by F_UNLCK, F_RDLCK or F_WRLCK */
-
-int nisam_lock_database(N_INFO *info, int lock_type)
-{
- int error;
- uint count;
- ISAM_SHARE *share;
- uint flag;
- DBUG_ENTER("nisam_lock_database");
-
- flag=error=0;
-#ifndef NO_LOCKING
- share=info->s;
- if (share->base.options & HA_OPTION_READ_ONLY_DATA ||
- info->lock_type == lock_type)
- DBUG_RETURN(0);
- pthread_mutex_lock(&share->intern_lock);
- switch (lock_type) {
- case F_UNLCK:
- if (info->lock_type == F_RDLCK)
- count= --share->r_locks;
- else
- count= --share->w_locks;
- if (info->lock_type == F_WRLCK && !share->w_locks &&
- flush_key_blocks(dflt_key_cache,share->kfile,FLUSH_KEEP))
- error=my_errno;
- if (info->opt_flag & (READ_CACHE_USED | WRITE_CACHE_USED))
- if (end_io_cache(&info->rec_cache))
- error=my_errno;
-
- if (!count)
- {
- if (share->changed && !share->w_locks)
- {
- share->state.process= share->last_process=share->this_process;
- share->state.loop= info->last_loop= ++info->this_loop;
- share->state.uniq= info->last_uniq= info->this_uniq;
- if (my_pwrite(share->kfile,(char*) &share->state.header,
- share->state_length,0L,MYF(MY_NABP)))
- error=my_errno;
- share->changed=0;
-#ifdef __WIN__
- if (nisam_flush)
- {
- _commit(share->kfile);
- _commit(info->dfile);
- }
- else
- share->not_flushed=1;
-#endif
- }
- if (share->r_locks)
- { /* Only read locks left */
- flag=1;
- if (my_lock(share->kfile,F_RDLCK,0L,F_TO_EOF,
- MYF(MY_WME | MY_SEEK_NOT_DONE)) && !error)
- error=my_errno;
- }
- else if (!share->w_locks)
- { /* No more locks */
- flag=1;
- if (my_lock(share->kfile,F_UNLCK,0L,F_TO_EOF,
- MYF(MY_WME | MY_SEEK_NOT_DONE)) && !error)
- error=my_errno;
- }
- }
- info->opt_flag&= ~(READ_CACHE_USED | WRITE_CACHE_USED);
- info->lock_type= F_UNLCK;
- break;
- case F_RDLCK:
- if (info->lock_type == F_WRLCK)
- { /* Change RW to READONLY */
- if (share->w_locks == 1)
- {
- flag=1;
- if (my_lock(share->kfile,lock_type,0L,F_TO_EOF,
- MYF(MY_SEEK_NOT_DONE)))
- {
- error=my_errno;
- break;
- }
- }
- share->w_locks--;
- share->r_locks++;
- info->lock_type=lock_type;
- break;
- }
- if (!share->r_locks && !share->w_locks)
- {
- flag=1;
-#ifdef HAVE_FCNTL
- if (my_lock(share->kfile,lock_type,0L,F_TO_EOF,info->lock_wait))
- {
- error=my_errno;
- break;
- }
- if (my_pread(share->kfile,
- (char*) &share->state.header,share->state_length,0L,
- MYF(MY_NABP)))
- {
- error=my_errno;
- VOID(my_lock(share->kfile,F_UNLCK,0L,F_TO_EOF,MYF(MY_SEEK_NOT_DONE)));
- my_errno=error;
- break;
- }
-#else
- VOID(my_seek(share->kfile,0L,MY_SEEK_SET,MYF(0)));
- if (my_lock(share->kfile,lock_type,0L,F_TO_EOF,info->lock_wait))
- {
- error=my_errno;
- break;
- }
- if (my_read(share->kfile,
- (char*) &share->state.header,share->state_length,
- MYF(MY_NABP)))
- {
- error=my_errno;
- VOID(my_lock(share->kfile,F_UNLCK,0L,F_TO_EOF,info->lock_wait));
- my_errno=error;
- break;
- }
-#endif
- }
- VOID(_nisam_test_if_changed(info));
- share->r_locks++;
- info->lock_type=lock_type;
- break;
- case F_WRLCK:
- if (info->lock_type == F_RDLCK)
- { /* Change RW to READONLY */
- if (share->r_locks == 1)
- {
- flag=1;
- if (my_lock(share->kfile,lock_type,0L,F_TO_EOF,
- MYF(info->lock_wait | MY_SEEK_NOT_DONE)))
- {
- error=my_errno;
- break;
- }
- share->r_locks--;
- share->w_locks++;
- info->lock_type=lock_type;
- break;
- }
- }
- if (!(share->base.options & HA_OPTION_READ_ONLY_DATA) && !share->w_locks)
- {
- flag=1;
- VOID(my_seek(share->kfile,0L,MY_SEEK_SET,MYF(0)));
- if (my_lock(share->kfile,lock_type,0L,F_TO_EOF,info->lock_wait))
- {
- error=my_errno;
- break;
- }
- if (!share->r_locks)
- {
- if (my_read(share->kfile,
- (char*) &share->state.header,share->state_length,
- MYF(MY_NABP)))
- {
- error=my_errno;
- VOID(my_lock(share->kfile,F_UNLCK,0L,F_TO_EOF,info->lock_wait));
- my_errno=error;
- break;
- }
- }
- }
- VOID(_nisam_test_if_changed(info));
- info->lock_type=lock_type;
- share->w_locks++;
- break;
- default:
- break; /* Impossible */
- }
- pthread_mutex_unlock(&share->intern_lock);
-#if defined(FULL_LOG) || defined(_lint)
- lock_type|=(int) (flag << 8); /* Set bit to set if real lock */
- nisam_log_command(LOG_LOCK,info,(byte*) &lock_type,sizeof(lock_type),
- error);
-#endif
-#endif
- DBUG_RETURN(error);
-} /* nisam_lock_database */
-
-
- /* Is used before access to database is granted */
-
-int _nisam_readinfo(register N_INFO *info, int lock_type, int check_keybuffer)
-{
- ISAM_SHARE *share;
- DBUG_ENTER("_nisam_readinfo");
-
- share=info->s;
- if (info->lock_type == F_UNLCK)
- {
- if (!share->r_locks && !share->w_locks)
- {
-#ifndef HAVE_FCNTL
- VOID(my_seek(share->kfile,0L,MY_SEEK_SET,MYF(0)));
-#endif
-#ifndef NO_LOCKING
-#ifdef UNSAFE_LOCKING
- if ((info->tmp_lock_type=lock_type) != F_RDLCK)
-#endif
- if (my_lock(share->kfile,lock_type,0L,F_TO_EOF,info->lock_wait))
- DBUG_RETURN(1);
-#endif
-#ifdef HAVE_FCNTL
- if (my_pread(share->kfile,
- (char*) &share->state.header,share->state_length,0L,
- MYF(MY_NABP)))
-#else
- if (my_read(share->kfile,
- (char*) &share->state.header,share->state_length,
- MYF(MY_NABP)))
-#endif
- {
-#ifndef NO_LOCKING
- int error=my_errno;
- VOID(my_lock(share->kfile,F_UNLCK,0L,F_TO_EOF,
- MYF(MY_SEEK_NOT_DONE)));
- my_errno=error;
-#endif
- DBUG_RETURN(1);
- }
- }
- if (check_keybuffer)
- VOID(_nisam_test_if_changed(info));
- }
- else if (lock_type == F_WRLCK && info->lock_type == F_RDLCK)
- {
- my_errno=EACCES; /* Not allowed to change */
- DBUG_RETURN(-1); /* when have read_lock() */
- }
- DBUG_RETURN(0);
-} /* _nisam_readinfo */
-
-
- /* Every isam-function that uppdates the isam-database must! end */
- /* with this request */
- /* ARGSUSED */
-
-int _nisam_writeinfo(register N_INFO *info, uint flags)
-{
- int error,olderror;
- ISAM_SHARE *share;
- DBUG_ENTER("_nisam_writeinfo");
-
- error=0;
- share=info->s;
- if (share->r_locks == 0 && share->w_locks == 0)
- {
- olderror=my_errno; /* Remember last error */
- if (flags)
- { /* Two threads can't be here */
- share->state.process= share->last_process= share->this_process;
- share->state.loop= info->last_loop= ++info->this_loop;
- share->state.uniq= info->last_uniq= info->this_uniq;
- if ((error=my_pwrite(share->kfile,(char*) &share->state.header,
- share->state_length,0L,MYF(MY_NABP)) != 0))
- olderror=my_errno;
-#ifdef __WIN__
- if (nisam_flush)
- {
- _commit(share->kfile);
- _commit(info->dfile);
- }
-#endif
- }
- if (flags != 2)
- {
-#ifndef NO_LOCKING
-#ifdef UNSAFE_LOCKING
- if (info->tmp_lock_type != F_RDLCK)
-#endif
- {
- if (my_lock(share->kfile,F_UNLCK,0L,F_TO_EOF,
- MYF(MY_WME | MY_SEEK_NOT_DONE)) && !error)
- DBUG_RETURN(1);
- }
-#endif
- }
- my_errno=olderror;
- }
- else if (flags)
- share->changed= 1; /* Mark keyfile changed */
- DBUG_RETURN(error);
-} /* _nisam_writeinfo */
-
-
- /* Test if someone has changed the database */
- /* (Should be called after readinfo) */
-
-int _nisam_test_if_changed(register N_INFO *info)
-{
-#ifndef NO_LOCKING
- {
- ISAM_SHARE *share=info->s;
- if (share->state.process != share->last_process ||
- share->state.loop != info->last_loop ||
- share->state.uniq != info->last_uniq)
- { /* Keyfile has changed */
- if (share->state.process != share->this_process)
- VOID(flush_key_blocks(dflt_key_cache,share->kfile,FLUSH_RELEASE));
- share->last_process=share->state.process;
- info->last_loop= share->state.loop;
- info->last_uniq= share->state.uniq;
- info->update|= HA_STATE_WRITTEN; /* Must use file on next */
- info->data_changed= 1; /* For nisam_is_changed */
- return 1;
- }
- }
-#endif
- return (!(info->update & HA_STATE_AKTIV) ||
- (info->update & (HA_STATE_WRITTEN | HA_STATE_DELETED |
- HA_STATE_KEY_CHANGED)));
-} /* _nisam_test_if_changed */
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