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2 
3 Copyright (c) 1996, 2013, Oracle and/or its affiliates. All Rights Reserved.
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22 this program; if not, write to the Free Software Foundation, Inc.,
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25 *****************************************************************************/
26 
27 /**************************************************//**
28 @file include/trx0types.h
29 Transaction system global type definitions
30 
31 Created 3/26/1996 Heikki Tuuri
32 *******************************************************/
33 
34 #ifndef trx0types_h
35 #define trx0types_h
36 
37 #include "ut0byte.h"
38 
39 /** printf(3) format used for printing DB_TRX_ID and other system fields */
40 #define TRX_ID_FMT		IB_ID_FMT
41 
42 /** maximum length that a formatted trx_t::id could take, not including
43 the terminating NUL character. */
44 #define TRX_ID_MAX_LEN		17
45 
46 /** Transaction execution states when trx->state == TRX_STATE_ACTIVE */
47 enum trx_que_t {
48 	TRX_QUE_RUNNING,		/*!< transaction is running */
49 	TRX_QUE_LOCK_WAIT,		/*!< transaction is waiting for
50 					a lock */
51 	TRX_QUE_ROLLING_BACK,		/*!< transaction is rolling back */
52 	TRX_QUE_COMMITTING		/*!< transaction is committing */
53 };
54 
55 /** Transaction states (trx_t::state) */
56 enum trx_state_t {
57 	TRX_STATE_NOT_STARTED,
58 	TRX_STATE_ACTIVE,
59 	TRX_STATE_PREPARED,			/* Support for 2PC/XA */
60 	TRX_STATE_COMMITTED_IN_MEMORY
61 };
62 
63 /** Type of data dictionary operation */
64 enum trx_dict_op_t {
65 	/** The transaction is not modifying the data dictionary. */
66 	TRX_DICT_OP_NONE = 0,
67 	/** The transaction is creating a table or an index, or
68 	dropping a table.  The table must be dropped in crash
69 	recovery.  This and TRX_DICT_OP_NONE are the only possible
70 	operation modes in crash recovery. */
71 	TRX_DICT_OP_TABLE = 1,
72 	/** The transaction is creating or dropping an index in an
73 	existing table.  In crash recovery, the data dictionary
74 	must be locked, but the table must not be dropped. */
75 	TRX_DICT_OP_INDEX = 2
76 };
77 
78 /** Memory objects */
79 /* @{ */
80 /** Transaction */
81 struct trx_t;
82 /** The locks and state of an active transaction */
83 struct trx_lock_t;
84 /** Transaction system */
85 struct trx_sys_t;
86 /** Signal */
87 struct trx_sig_t;
88 /** Rollback segment */
89 struct trx_rseg_t;
90 /** Transaction undo log */
91 struct trx_undo_t;
92 /** Array of undo numbers of undo records being rolled back or purged */
93 struct trx_undo_arr_t;
94 /** A cell of trx_undo_arr_t */
95 struct trx_undo_inf_t;
96 /** The control structure used in the purge operation */
97 struct trx_purge_t;
98 /** Rollback command node in a query graph */
99 struct roll_node_t;
100 /** Commit command node in a query graph */
101 struct commit_node_t;
102 /** SAVEPOINT command node in a query graph */
103 struct trx_named_savept_t;
104 /* @} */
105 
106 /** Rollback contexts */
107 enum trx_rb_ctx {
108 	RB_NONE = 0,	/*!< no rollback */
109 	RB_NORMAL,	/*!< normal rollback */
110 	RB_RECOVERY_PURGE_REC,
111 			/*!< rolling back an incomplete transaction,
112 			in crash recovery, rolling back an
113 			INSERT that was performed by updating a
114 			delete-marked record; if the delete-marked record
115 			no longer exists in an active read view, it will
116 			be purged */
117 	RB_RECOVERY	/*!< rolling back an incomplete transaction,
118 			in crash recovery */
119 };
120 
121 /** Row identifier (DB_ROW_ID, DATA_ROW_ID) */
122 typedef ib_id_t	row_id_t;
123 /** Transaction identifier (DB_TRX_ID, DATA_TRX_ID) */
124 typedef ib_id_t	trx_id_t;
125 /** Rollback pointer (DB_ROLL_PTR, DATA_ROLL_PTR) */
126 typedef ib_id_t	roll_ptr_t;
127 /** Undo number */
128 typedef ib_id_t	undo_no_t;
129 
130 /** Maximum transaction identifier */
131 #define TRX_ID_MAX	IB_ID_MAX
132 
133 /** Transaction savepoint */
134 struct trx_savept_t{
135 	undo_no_t	least_undo_no;	/*!< least undo number to undo */
136 };
137 
138 /** File objects */
139 /* @{ */
140 /** Transaction system header */
141 typedef byte	trx_sysf_t;
142 /** Rollback segment header */
143 typedef byte	trx_rsegf_t;
144 /** Undo segment header */
145 typedef byte	trx_usegf_t;
146 /** Undo log header */
147 typedef byte	trx_ulogf_t;
148 /** Undo log page header */
149 typedef byte	trx_upagef_t;
150 
151 /** Undo log record */
152 typedef	byte	trx_undo_rec_t;
153 /* @} */
154 
155 #endif
156