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wait_event_funcs.c
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1 /*------------------------------------------------------------------------
2  *
3  * wait_event_funcs.c
4  * Functions for accessing wait event data.
5  *
6  * Portions Copyright (c) 1996-2024, PostgreSQL Global Development Group
7  * Portions Copyright (c) 1994, Regents of the University of California
8  *
9  *
10  * IDENTIFICATION
11  * src/backend/utils/activity/wait_event_funcs.c
12  *
13  *------------------------------------------------------------------------
14  */
15 #include "postgres.h"
16 
17 #include "funcapi.h"
18 #include "utils/builtins.h"
19 #include "utils/wait_event.h"
20 
21 /*
22  * Each wait event has one corresponding entry in this structure, fed to
23  * the SQL function of this file.
24  */
25 static const struct
26 {
27  const char *type;
28  const char *name;
29  const char *description;
30 }
31 
32  waitEventData[] =
33 {
34 #include "wait_event_funcs_data.c"
35  /* end of list */
36  {NULL, NULL, NULL}
37 };
38 
39 
40 /*
41  * pg_get_wait_events
42  *
43  * List information about wait events (type, name and description).
44  */
45 Datum
47 {
48 #define PG_GET_WAIT_EVENTS_COLS 3
49  ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
50  char **waiteventnames;
51  int nbwaitevents;
52 
53  /* Build tuplestore to hold the result rows */
54  InitMaterializedSRF(fcinfo, 0);
55 
56  /* Iterate over the list of wait events */
57  for (int idx = 0; waitEventData[idx].type != NULL; idx++)
58  {
60  bool nulls[PG_GET_WAIT_EVENTS_COLS] = {0};
61 
65 
66  tuplestore_putvalues(rsinfo->setResult, rsinfo->setDesc, values, nulls);
67  }
68 
69  /* Handle custom wait events for extensions */
71  &nbwaitevents);
72 
73  for (int idx = 0; idx < nbwaitevents; idx++)
74  {
77  bool nulls[PG_GET_WAIT_EVENTS_COLS] = {0};
78 
79 
80  values[0] = CStringGetTextDatum("Extension");
81  values[1] = CStringGetTextDatum(waiteventnames[idx]);
82 
85  "Waiting for custom wait event \"%s\" defined by extension module",
86  waiteventnames[idx]);
87 
88  values[2] = CStringGetTextDatum(buf.data);
89 
90  tuplestore_putvalues(rsinfo->setResult, rsinfo->setDesc, values, nulls);
91  }
92 
93  /* Likewise for injection points */
95  &nbwaitevents);
96 
97  for (int idx = 0; idx < nbwaitevents; idx++)
98  {
101  bool nulls[PG_GET_WAIT_EVENTS_COLS] = {0};
102 
103 
104  values[0] = CStringGetTextDatum("InjectionPoint");
105  values[1] = CStringGetTextDatum(waiteventnames[idx]);
106 
109  "Waiting for injection point \"%s\"",
110  waiteventnames[idx]);
111 
112  values[2] = CStringGetTextDatum(buf.data);
113 
114  tuplestore_putvalues(rsinfo->setResult, rsinfo->setDesc, values, nulls);
115  }
116 
117  return (Datum) 0;
118 }
Datum idx(PG_FUNCTION_ARGS)
Definition: _int_op.c:259
static Datum values[MAXATTR]
Definition: bootstrap.c:152
#define CStringGetTextDatum(s)
Definition: builtins.h:97
#define PG_FUNCTION_ARGS
Definition: fmgr.h:193
void InitMaterializedSRF(FunctionCallInfo fcinfo, bits32 flags)
Definition: funcapi.c:76
static char * buf
Definition: pg_test_fsync.c:73
uintptr_t Datum
Definition: postgres.h:64
void appendStringInfo(StringInfo str, const char *fmt,...)
Definition: stringinfo.c:97
void initStringInfo(StringInfo str)
Definition: stringinfo.c:59
TupleDesc setDesc
Definition: execnodes.h:340
Tuplestorestate * setResult
Definition: execnodes.h:339
void tuplestore_putvalues(Tuplestorestate *state, TupleDesc tdesc, const Datum *values, const bool *isnull)
Definition: tuplestore.c:782
char ** GetWaitEventCustomNames(uint32 classId, int *nwaitevents)
Definition: wait_event.c:307
#define PG_WAIT_INJECTIONPOINT
Definition: wait_event.h:27
#define PG_WAIT_EXTENSION
Definition: wait_event.h:23
const char * description
const char * type
#define PG_GET_WAIT_EVENTS_COLS
static const struct @23 waitEventData[]
const char * name
Datum pg_get_wait_events(PG_FUNCTION_ARGS)