MySQL  8.0.16
Source Code Documentation
sql_callback.h
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1 /*
2  Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved.
3 
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15  This program is distributed in the hope that it will be useful,
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17  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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23 */
24 
25 #ifndef SQL_CALLBACK_INCLUDED
26 #define SQL_CALLBACK_INCLUDED
27 
28 /**
29  Macro used for an internal callback.
30 
31  The macro will check that the object exists and that the function
32  is defined. If that is the case, it will call the function with the
33  given parameters.
34 
35  If the object or the function is not defined, the callback will be
36  considered successful (nothing needed to be done) and will
37  therefore return no error.
38  */
39 
40 #define MYSQL_CALLBACK(OBJ, FUNC, PARAMS) \
41  do { \
42  if ((OBJ) && ((OBJ)->FUNC)) (OBJ)->FUNC PARAMS; \
43  } while (0)
44 
45 #define MYSQL_CALLBACK_ELSE(OBJ, FUNC, PARAMS, ELSE) \
46  (((OBJ) && ((OBJ)->FUNC)) ? (OBJ)->FUNC PARAMS : (ELSE))
47 
48 #endif /* SQL_CALLBACK_INCLUDED */