Drizzled Public API Documentation

mi_update.cc
1 /* Copyright (C) 2000-2006 MySQL AB
2 
3  This program is free software; you can redistribute it and/or modify
4  it under the terms of the GNU General Public License as published by
5  the Free Software Foundation; version 2 of the License.
6 
7  This program is distributed in the hope that it will be useful,
8  but WITHOUT ANY WARRANTY; without even the implied warranty of
9  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
10  GNU General Public License for more details.
11 
12  You should have received a copy of the GNU General Public License
13  along with this program; if not, write to the Free Software
14  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */
15 
16 /* Update an old row in a MyISAM table */
17 
18 #include "myisam_priv.h"
19 #include <drizzled/util/test.h>
20 
21 using namespace drizzled;
22 
23 int mi_update(register MI_INFO *info, const unsigned char *oldrec, unsigned char *newrec)
24 {
25  int key_changed,save_errno;
26  register internal::my_off_t pos;
27  uint32_t i;
28  unsigned char old_key[MI_MAX_KEY_BUFF],*new_key;
29  bool auto_key_changed=0;
30  uint64_t changed;
31  MYISAM_SHARE *share= info->s;
32  ha_checksum old_checksum= 0;
33 
34  if (!(info->update & HA_STATE_AKTIV))
35  {
36  return(errno=HA_ERR_KEY_NOT_FOUND);
37  }
38  if (share->options & HA_OPTION_READ_ONLY_DATA)
39  {
40  return(errno=EACCES);
41  }
42  if (info->state->key_file_length >= share->base.margin_key_file_length)
43  {
44  return(errno=HA_ERR_INDEX_FILE_FULL);
45  }
46  pos=info->lastpos;
47  if (_mi_readinfo(info,F_WRLCK,1))
48  return(errno);
49 
50  if (share->calc_checksum)
51  old_checksum=info->checksum=(*share->calc_checksum)(info,oldrec);
52  if ((*share->compare_record)(info,oldrec))
53  {
54  save_errno=errno;
55  goto err_end; /* Record has changed */
56  }
57 
58 
59  /* Calculate and check all unique constraints */
60  key_changed=0;
61  for (i=0 ; i < share->state.header.uniques ; i++)
62  {
63  MI_UNIQUEDEF *def=share->uniqueinfo+i;
64  if (mi_unique_comp(def, newrec, oldrec,1) &&
65  mi_check_unique(info, def, newrec, mi_unique_hash(def, newrec),
66  info->lastpos))
67  {
68  save_errno=errno;
69  goto err_end;
70  }
71  }
72  if (_mi_mark_file_changed(info))
73  {
74  save_errno=errno;
75  goto err_end;
76  }
77 
78  /* Check which keys changed from the original row */
79 
80  new_key=info->lastkey2;
81  changed=0;
82  for (i=0 ; i < share->base.keys ; i++)
83  {
84  if (mi_is_key_active(share->state.key_map, i))
85  {
86  {
87  uint32_t new_length=_mi_make_key(info,i,new_key,newrec,pos);
88  uint32_t old_length=_mi_make_key(info,i,old_key,oldrec,pos);
89 
90  /* The above changed info->lastkey2. Inform mi_rnext_same(). */
91  info->update&= ~HA_STATE_RNEXT_SAME;
92 
93  if (new_length != old_length ||
94  memcmp(old_key,new_key,new_length))
95  {
96  if ((int) i == info->lastinx)
97  key_changed|=HA_STATE_WRITTEN; /* Mark that keyfile changed */
98  changed|=((uint64_t) 1 << i);
99  share->keyinfo[i].version++;
100  if (share->keyinfo[i].ck_delete(info,i,old_key,old_length)) goto err;
101  if (share->keyinfo[i].ck_insert(info,i,new_key,new_length)) goto err;
102  if (share->base.auto_key == i+1)
103  auto_key_changed=1;
104  }
105  }
106  }
107  }
108  /*
109  If we are running with external locking, we must update the index file
110  that something has changed.
111  */
112  if (changed)
113  key_changed|= HA_STATE_CHANGED;
114 
115  if (share->calc_checksum)
116  {
117  info->checksum=(*share->calc_checksum)(info,newrec);
118  /* Store new checksum in index file header */
119  key_changed|= HA_STATE_CHANGED;
120  }
121  {
122  /*
123  Don't update index file if data file is not extended and no status
124  information changed
125  */
126  MI_STATUS_INFO state;
127  ha_rows org_split;
128  internal::my_off_t org_delete_link;
129 
130  memcpy(&state, info->state, sizeof(state));
131  org_split= share->state.split;
132  org_delete_link= share->state.dellink;
133  if ((*share->update_record)(info,pos,newrec))
134  goto err;
135  if (!key_changed &&
136  (memcmp(&state, info->state, sizeof(state)) ||
137  org_split != share->state.split ||
138  org_delete_link != share->state.dellink))
139  key_changed|= HA_STATE_CHANGED; /* Must update index file */
140  }
141  if (auto_key_changed)
142  set_if_bigger(info->s->state.auto_increment,
143  retrieve_auto_increment(info, newrec));
144  if (share->calc_checksum)
145  info->state->checksum+=(info->checksum - old_checksum);
146 
147  info->update= (HA_STATE_CHANGED | HA_STATE_ROW_CHANGED | HA_STATE_AKTIV |
148  key_changed);
149  /*
150  Every myisam function that updates myisam table must end with
151  call to _mi_writeinfo(). If operation (second param of
152  _mi_writeinfo()) is not 0 it sets share->changed to 1, that is
153  flags that data has changed. If operation is 0, this function
154  equals to no-op in this case.
155 
156  mi_update() must always pass !0 value as operation, since even if
157  there is no index change there could be data change.
158  */
159  _mi_writeinfo(info, WRITEINFO_UPDATE_KEYFILE);
160  return(0);
161 
162 err:
163  save_errno=errno;
164  if (changed)
165  key_changed|= HA_STATE_CHANGED;
166  if (errno == HA_ERR_FOUND_DUPP_KEY || errno == HA_ERR_OUT_OF_MEM ||
167  errno == HA_ERR_RECORD_FILE_FULL)
168  {
169  info->errkey= (int) i;
170  int flag=0;
171  do
172  {
173  if (((uint64_t) 1 << i) & changed)
174  {
175  {
176  uint32_t new_length=_mi_make_key(info,i,new_key,newrec,pos);
177  uint32_t old_length= _mi_make_key(info,i,old_key,oldrec,pos);
178  if ((flag++ && _mi_ck_delete(info,i,new_key,new_length)) ||
179  _mi_ck_write(info,i,old_key,old_length))
180  break;
181  }
182  }
183  } while (i-- != 0);
184  }
185  else
186  {
187  mi_print_error(info->s, HA_ERR_CRASHED);
188  mi_mark_crashed(info);
189  }
190  info->update= (HA_STATE_CHANGED | HA_STATE_AKTIV | HA_STATE_ROW_CHANGED |
191  key_changed);
192 
193  err_end:
194  _mi_writeinfo(info,WRITEINFO_UPDATE_KEYFILE);
195  if (save_errno == HA_ERR_KEY_NOT_FOUND)
196  {
197  mi_print_error(info->s, HA_ERR_CRASHED);
198  save_errno=HA_ERR_CRASHED;
199  }
200  return(errno=save_errno);
201 } /* mi_update */
TODO: Rename this file - func.h is stupid.