MySQL 9.0.0
Source Code Documentation
sdi_utils.h
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23
24#ifndef DD__SDI_UTILS_INCLUDED
25#define DD__SDI_UTILS_INCLUDED
26
27#include <assert.h>
28
29#include "sql/current_thd.h" // inline_current_thd
30#include "sql/dd/string_type.h" // dd::String_type
31#include "sql/error_handler.h" // Internal_error_handler
32#include "sql/mdl.h" // MDL_request
33#include "sql/sql_class.h" // THD
34
35#ifndef NDEBUG
36#define ENTITY_FMT "(%s, %llu)"
37#define ENTITY_VAL(obj) (obj).name().c_str(), (obj).id()
38#endif /* !NDEBUG */
39
40/**
41 @file
42 @ingroup sdi
43
44 Inline utility functions used in different
45 TUs. Declared inline in header to avoid any overhead as they are
46 only a syntactic convnience (macro replacement).
47*/
48
49namespace dd {
50namespace sdi_utils {
51
52/**
53 In debug mode, check that a true argument is paired with
54 thd->is_error() or thd->killed being set. In optimized mode it turns into
55 a noop.
56 @param[in] ret return value to check
57 @return same as argument passed in
58 */
59inline bool checked_return(bool ret) {
60#ifndef NDEBUG
61 THD *cthd = current_thd;
62 assert(!ret || cthd->is_system_thread() || cthd->is_error() || cthd->killed);
63#endif /*!NDEBUG*/
64 return ret;
65}
66
67/**
68 Convenience function for obtaining MDL. Sets up the MDL_request
69 struct and populates it, before calling Mdl_context::acquire_lock.
70
71 @param thd thread context
72 @param ns MDL key namespace
73 @param schema_name schema name
74 @param object_name object name
75 @param mt MDL type
76 @param md MDL duration
77 @return value from Mdl_context::acquire_lock
78 */
80 const String_type &schema_name,
81 const String_type &object_name,
85 MDL_REQUEST_INIT(&mdl_request, ns, schema_name.c_str(), object_name.c_str(),
86 mt, md);
88 &mdl_request, thd->variables.lock_wait_timeout));
89}
90
91template <typename T>
92const T &ptr_as_cref(const T *p) {
93 assert(p != nullptr);
94 return *p;
95}
96
97/**
98 Class template which derives from Internal_error_handler and
99 overrides handle_condition with the CONDITION_HANDLER_CLOS template
100 parameter.
101 */
102template <typename CONDITION_HANDLER_CLOS>
104 CONDITION_HANDLER_CLOS m_ch;
105 bool handle_condition(THD *, uint sql_errno, const char *sqlstate,
107 const char *msg) override {
108 return m_ch(sql_errno, sqlstate, level, msg);
109 }
110
111 public:
112 // CONDITION_HANDLER_CLOS is *class* template argument, so there is no type
113 // deduction, and ch must refer to an R-value. So it is safe to move.
114 explicit Closure_error_handler(CONDITION_HANDLER_CLOS &&ch)
115 : m_ch(std::move(ch)) {}
116};
117
118/**
119 Set up a custom error handler to use for errors from the execution
120 of a closure.
121
122 @param thd thread context
123 @param chc closure which implements the
124 Internal_error_handler::handle_condition override
125 @param ac closure action for which error conditions should be handled.
126 @retval true if an error occurs
127 @retval false otherwise
128 */
129template <typename CH_CLOS, typename ACTION_CLOS>
130bool handle_errors(THD *thd, CH_CLOS &&chc, ACTION_CLOS &&ac) {
131 Closure_error_handler<CH_CLOS> eh{std::forward<CH_CLOS>(chc)};
132 thd->push_internal_handler(&eh);
133 bool r = ac();
135 return r;
136}
137
138template <typename P_TYPE, typename CLOS_TYPE>
139std::unique_ptr<P_TYPE, CLOS_TYPE> make_guard(P_TYPE *p, CLOS_TYPE &&clos) {
140 return std::unique_ptr<P_TYPE, CLOS_TYPE>(p, std::forward<CLOS_TYPE>(clos));
141}
142
143} // namespace sdi_utils
144} // namespace dd
145#endif // DD__SDI_UTILS_INCLUDED
This class represents the interface for internal error handlers.
Definition: error_handler.h:47
bool acquire_lock(MDL_request *mdl_request, Timeout_type lock_wait_timeout)
Acquire one lock with waiting for conflicting locks to go away if needed.
Definition: mdl.cc:3361
A pending metadata lock request.
Definition: mdl.h:802
enum_severity_level
Enumeration value describing the severity of the condition.
Definition: sql_error.h:63
For each client connection we create a separate thread with THD serving as a thread/connection descri...
Definition: sql_lexer_thd.h:36
MDL_context mdl_context
Definition: sql_class.h:966
bool is_error() const
true if there is an error in the error stack.
Definition: sql_class.h:3286
bool is_system_thread() const
Definition: sql_class.h:2545
Internal_error_handler * pop_internal_handler()
Remove the error handler last pushed.
Definition: sql_class.cc:932
void push_internal_handler(Internal_error_handler *handler)
Add an internal error handler to the thread execution context.
Definition: sql_class.cc:911
System_variables variables
Definition: sql_lexer_thd.h:64
std::atomic< killed_state > killed
Definition: sql_class.h:2726
Class template which derives from Internal_error_handler and overrides handle_condition with the COND...
Definition: sdi_utils.h:103
Closure_error_handler(CONDITION_HANDLER_CLOS &&ch)
Definition: sdi_utils.h:114
bool handle_condition(THD *, uint sql_errno, const char *sqlstate, Sql_condition::enum_severity_level *level, const char *msg) override
Handle a sql condition.
Definition: sdi_utils.h:105
CONDITION_HANDLER_CLOS m_ch
Definition: sdi_utils.h:104
const char * p
Definition: ctype-mb.cc:1225
thread_local THD * current_thd
Definition: current_thd.cc:26
#define MDL_REQUEST_INIT(R, P1, P2, P3, P4, P5)
Definition: mdl.h:906
enum_mdl_duration
Duration of metadata lock.
Definition: mdl.h:333
@ MDL_TRANSACTION
Locks with transaction duration are automatically released at the end of transaction.
Definition: mdl.h:343
bool handle_errors(THD *thd, CH_CLOS &&chc, ACTION_CLOS &&ac)
Set up a custom error handler to use for errors from the execution of a closure.
Definition: sdi_utils.h:130
const T & ptr_as_cref(const T *p)
Definition: sdi_utils.h:92
std::unique_ptr< P_TYPE, CLOS_TYPE > make_guard(P_TYPE *p, CLOS_TYPE &&clos)
Definition: sdi_utils.h:139
bool mdl_lock(THD *thd, MDL_key::enum_mdl_namespace ns, const String_type &schema_name, const String_type &object_name, enum_mdl_type mt=MDL_EXCLUSIVE, enum_mdl_duration md=MDL_TRANSACTION)
Convenience function for obtaining MDL.
Definition: sdi_utils.h:79
bool checked_return(bool ret)
In debug mode, check that a true argument is paired with thd->is_error() or thd->killed being set.
Definition: sdi_utils.h:59
MDL_request * mdl_request(const Import_target &t, MEM_ROOT *mem_root)
Creates an MDL_request for exclusive MDL on the table being imported.
Definition: sdi_api.cc:247
The version of the current data dictionary table definitions.
Definition: dictionary_client.h:43
Char_string_template< String_type_allocator > String_type
Definition: string_type.h:51
Definition: gcs_xcom_synode.h:64
const mysql_service_registry_t * r
Definition: pfs_example_plugin_employee.cc:86
enum_mdl_type
Type of metadata lock request.
Definition: sql_lexer_yacc_state.h:106
@ MDL_EXCLUSIVE
Definition: sql_lexer_yacc_state.h:236
enum_mdl_namespace
Object namespaces.
Definition: mdl.h:400