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ha_tina.h
1 /* Copyright (c) 2003, 2011, Oracle and/or its affiliates. All rights reserved.
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 #include <sys/types.h>
17 #include <sys/stat.h>
18 #include <my_dir.h>
19 #include "transparent_file.h"
20 
21 #define DEFAULT_CHAIN_LENGTH 512
22 /*
23  Version for file format.
24  1 - Initial Version. That is, the version when the metafile was introduced.
25 */
26 
27 #define TINA_VERSION 1
28 
29 typedef struct st_tina_share {
30  char *table_name;
31  char data_file_name[FN_REFLEN];
32  uint table_name_length, use_count;
33  /*
34  Below flag is needed to make log tables work with concurrent insert.
35  For more details see comment to ha_tina::update_status.
36  */
37  my_bool is_log_table;
38  /*
39  Here we save the length of the file for readers. This is updated by
40  inserts, updates and deletes. The var is initialized along with the
41  share initialization.
42  */
43  my_off_t saved_data_file_length;
44  mysql_mutex_t mutex;
45  THR_LOCK lock;
46  bool update_file_opened;
47  bool tina_write_opened;
48  File meta_file; /* Meta file we use */
49  File tina_write_filedes; /* File handler for readers */
50  bool crashed; /* Meta file is crashed */
51  ha_rows rows_recorded; /* Number of rows in tables */
52  uint data_file_version; /* Version of the data file used */
53 } TINA_SHARE;
54 
55 struct tina_set {
56  my_off_t begin;
57  my_off_t end;
58 };
59 
60 class ha_tina: public handler
61 {
62  THR_LOCK_DATA lock; /* MySQL lock */
63  TINA_SHARE *share; /* Shared lock info */
64  my_off_t current_position; /* Current position in the file during a file scan */
65  my_off_t next_position; /* Next position in the file scan */
66  my_off_t local_saved_data_file_length; /* save position for reads */
67  my_off_t temp_file_length;
68  uchar byte_buffer[IO_SIZE];
69  Transparent_file *file_buff;
70  File data_file; /* File handler for readers */
71  File update_temp_file;
72  String buffer;
73  /*
74  The chain contains "holes" in the file, occured because of
75  deletes/updates. It is used in rnd_end() to get rid of them
76  in the end of the query.
77  */
78  tina_set chain_buffer[DEFAULT_CHAIN_LENGTH];
79  tina_set *chain;
80  tina_set *chain_ptr;
81  uchar chain_alloced;
82  uint32 chain_size;
83  uint local_data_file_version; /* Saved version of the data file used */
84  bool records_is_known;
85  MEM_ROOT blobroot;
86 
87 private:
88  bool get_write_pos(my_off_t *end_pos, tina_set *closest_hole);
89  int open_update_temp_file_if_needed();
90  int init_tina_writer();
91  int init_data_file();
92 
93 public:
94  ha_tina(handlerton *hton, TABLE_SHARE *table_arg);
95  ~ha_tina()
96  {
97  if (chain_alloced)
98  my_free(chain);
99  if (file_buff)
100  delete file_buff;
101  free_root(&blobroot, MYF(0));
102  }
103  const char *table_type() const { return "CSV"; }
104  const char *index_type(uint inx) { return "NONE"; }
105  const char **bas_ext() const;
106  ulonglong table_flags() const
107  {
108  return (HA_NO_TRANSACTIONS | HA_REC_NOT_IN_SEQ | HA_NO_AUTO_INCREMENT |
109  HA_BINLOG_ROW_CAPABLE | HA_BINLOG_STMT_CAPABLE |
110  HA_CAN_REPAIR);
111  }
112  ulong index_flags(uint idx, uint part, bool all_parts) const
113  {
114  /*
115  We will never have indexes so this will never be called(AKA we return
116  zero)
117  */
118  return 0;
119  }
120  uint max_record_length() const { return HA_MAX_REC_LENGTH; }
121  uint max_keys() const { return 0; }
122  uint max_key_parts() const { return 0; }
123  uint max_key_length() const { return 0; }
124  /*
125  Called in test_quick_select to determine if indexes should be used.
126  */
127  virtual double scan_time() { return (double) (stats.records+stats.deleted) / 20.0+10; }
128  /* The next method will never be called */
129  virtual bool fast_key_read() { return 1;}
130  /*
131  TODO: return actual upper bound of number of records in the table.
132  (e.g. save number of records seen on full table scan and/or use file size
133  as upper bound)
134  */
135  ha_rows estimate_rows_upper_bound() { return HA_POS_ERROR; }
136 
137  int open(const char *name, int mode, uint open_options);
138  int close(void);
139  int write_row(uchar * buf);
140  int update_row(const uchar * old_data, uchar * new_data);
141  int delete_row(const uchar * buf);
142  int rnd_init(bool scan=1);
143  int rnd_next(uchar *buf);
144  int rnd_pos(uchar * buf, uchar *pos);
145  bool check_and_repair(THD *thd);
146  int check(THD* thd, HA_CHECK_OPT* check_opt);
147  bool is_crashed() const;
148  int rnd_end();
149  int repair(THD* thd, HA_CHECK_OPT* check_opt);
150  /* This is required for SQL layer to know that we support autorepair */
151  bool auto_repair() const { return 1; }
152  void position(const uchar *record);
153  int info(uint);
154  int extra(enum ha_extra_function operation);
155  int delete_all_rows(void);
156  int create(const char *name, TABLE *form, HA_CREATE_INFO *create_info);
157  bool check_if_incompatible_data(HA_CREATE_INFO *info,
158  uint table_changes);
159 
160  THR_LOCK_DATA **store_lock(THD *thd, THR_LOCK_DATA **to,
161  enum thr_lock_type lock_type);
162 
163  /*
164  These functions used to get/update status of the handler.
165  Needed to enable concurrent inserts.
166  */
167  void get_status();
168  void update_status();
169 
170  /* The following methods were added just for TINA */
171  int encode_quote(uchar *buf);
172  int find_current_row(uchar *buf);
173  int chain_append();
174 };
175