diff options
Diffstat (limited to 'heap/hp_rrnd.c')
| -rw-r--r-- | heap/hp_rrnd.c | 106 |
1 files changed, 106 insertions, 0 deletions
diff --git a/heap/hp_rrnd.c b/heap/hp_rrnd.c new file mode 100644 index 00000000000..63181967a29 --- /dev/null +++ b/heap/hp_rrnd.c @@ -0,0 +1,106 @@ +/* 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 */ + +/* Read a record from a random position */ + +#include "heapdef.h" + +/* + Returns one of following values: + 0 = Ok. + HA_ERR_RECORD_DELETED = Record is deleted. + HA_ERR_END_OF_FILE = EOF. +*/ + +int heap_rrnd(register HP_INFO *info, byte *record, byte *pos) +{ + HP_SHARE *share=info->s; + DBUG_ENTER("heap_rrnd"); + DBUG_PRINT("enter",("info: %lx pos: %lx",info,pos)); + + info->lastinx= -1; + if (!(info->current_ptr= pos)) + { + info->update= 0; + DBUG_RETURN(my_errno= HA_ERR_END_OF_FILE); + } + if (!info->current_ptr[share->reclength]) + { + info->update= HA_STATE_PREV_FOUND | HA_STATE_NEXT_FOUND; + DBUG_RETURN(my_errno=HA_ERR_RECORD_DELETED); + } + info->update=HA_STATE_PREV_FOUND | HA_STATE_NEXT_FOUND | HA_STATE_AKTIV; + memcpy(record,info->current_ptr,(size_t) share->reclength); + DBUG_PRINT("exit",("found record at %lx",info->current_ptr)); + info->current_hash_ptr=0; /* Can't use rnext */ + DBUG_RETURN(0); +} /* heap_rrnd */ + + +#ifdef WANT_OLD_HEAP_VERSION + +/* + If pos == -1 then read next record + Returns one of following values: + 0 = Ok. + HA_ERR_RECORD_DELETED = Record is deleted. + HA_ERR_END_OF_FILE = EOF. +*/ + +int heap_rrnd_old(register HP_INFO *info, byte *record, ulong pos) +{ + HP_SHARE *share=info->s; + DBUG_ENTER("heap_rrnd"); + DBUG_PRINT("enter",("info: %lx pos: %ld",info,pos)); + + info->lastinx= -1; + if (pos == (ulong) -1) + { + pos= ++info->current_record; + if (pos % share->block.records_in_block && /* Quick next record */ + pos < share->records+share->deleted && + (info->update & HA_STATE_PREV_FOUND)) + { + info->current_ptr+=share->block.recbuffer; + goto end; + } + } + else + info->current_record=pos; + + if (pos >= share->records+share->deleted) + { + info->update= 0; + DBUG_RETURN(my_errno= HA_ERR_END_OF_FILE); + } + + /* Find record number pos */ + _hp_find_record(info,pos); + +end: + if (!info->current_ptr[share->reclength]) + { + info->update= HA_STATE_PREV_FOUND | HA_STATE_NEXT_FOUND; + DBUG_RETURN(my_errno=HA_ERR_RECORD_DELETED); + } + info->update=HA_STATE_PREV_FOUND | HA_STATE_NEXT_FOUND | HA_STATE_AKTIV; + memcpy(record,info->current_ptr,(size_t) share->reclength); + DBUG_PRINT("exit",("found record at %lx",info->current_ptr)); + info->current_hash_ptr=0; /* Can't use rnext */ + DBUG_RETURN(0); +} /* heap_rrnd */ + +#endif /* WANT_OLD_HEAP_VERSION */ |