PostgreSQL Source Code  git master
rmgr.c
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1 /*
2  * rmgr.c
3  *
4  * Resource managers definition
5  *
6  * src/backend/access/transam/rmgr.c
7  */
8 #include "postgres.h"
9 
10 #include "access/rmgr.h"
11 #include "access/xlog_internal.h"
12 #include "fmgr.h"
13 #include "funcapi.h"
14 #include "miscadmin.h"
15 #include "nodes/execnodes.h"
16 #include "utils/builtins.h"
17 #include "utils/fmgrprotos.h"
18 #include "utils/tuplestore.h"
19 
20 /* includes needed for "access/rmgrlist.h" */
21 /* IWYU pragma: begin_keep */
22 #include "access/brin_xlog.h"
23 #include "access/clog.h"
24 #include "access/commit_ts.h"
25 #include "access/generic_xlog.h"
26 #include "access/ginxlog.h"
27 #include "access/gistxlog.h"
28 #include "access/hash_xlog.h"
29 #include "access/heapam_xlog.h"
30 #include "access/multixact.h"
31 #include "access/nbtxlog.h"
32 #include "access/spgxlog.h"
33 #include "access/xact.h"
34 #include "catalog/storage_xlog.h"
36 #include "commands/sequence.h"
37 #include "commands/tablespace.h"
38 #include "replication/decode.h"
39 #include "replication/message.h"
40 #include "replication/origin.h"
41 #include "storage/standby.h"
42 #include "utils/relmapper.h"
43 /* IWYU pragma: end_keep */
44 
45 
46 /* must be kept in sync with RmgrData definition in xlog_internal.h */
47 #define PG_RMGR(symname,name,redo,desc,identify,startup,cleanup,mask,decode) \
48  { name, redo, desc, identify, startup, cleanup, mask, decode },
49 
51 #include "access/rmgrlist.h"
52 };
53 
54 /*
55  * Start up all resource managers.
56  */
57 void
59 {
60  for (int rmid = 0; rmid <= RM_MAX_ID; rmid++)
61  {
62  if (!RmgrIdExists(rmid))
63  continue;
64 
65  if (RmgrTable[rmid].rm_startup != NULL)
66  RmgrTable[rmid].rm_startup();
67  }
68 }
69 
70 /*
71  * Clean up all resource managers.
72  */
73 void
75 {
76  for (int rmid = 0; rmid <= RM_MAX_ID; rmid++)
77  {
78  if (!RmgrIdExists(rmid))
79  continue;
80 
81  if (RmgrTable[rmid].rm_cleanup != NULL)
82  RmgrTable[rmid].rm_cleanup();
83  }
84 }
85 
86 /*
87  * Emit ERROR when we encounter a record with an RmgrId we don't
88  * recognize.
89  */
90 void
92 {
93  ereport(ERROR, (errmsg("resource manager with ID %d not registered", rmid),
94  errhint("Include the extension module that implements this resource manager in \"shared_preload_libraries\".")));
95 }
96 
97 /*
98  * Register a new custom WAL resource manager.
99  *
100  * Resource manager IDs must be globally unique across all extensions. Refer
101  * to https://wiki.postgresql.org/wiki/CustomWALResourceManagers to reserve a
102  * unique RmgrId for your extension, to avoid conflicts with other extension
103  * developers. During development, use RM_EXPERIMENTAL_ID to avoid needlessly
104  * reserving a new ID.
105  */
106 void
108 {
109  if (rmgr->rm_name == NULL || strlen(rmgr->rm_name) == 0)
110  ereport(ERROR, (errmsg("custom resource manager name is invalid"),
111  errhint("Provide a non-empty name for the custom resource manager.")));
112 
113  if (!RmgrIdIsCustom(rmid))
114  ereport(ERROR, (errmsg("custom resource manager ID %d is out of range", rmid),
115  errhint("Provide a custom resource manager ID between %d and %d.",
117 
119  ereport(ERROR,
120  (errmsg("failed to register custom resource manager \"%s\" with ID %d", rmgr->rm_name, rmid),
121  errdetail("Custom resource manager must be registered while initializing modules in \"shared_preload_libraries\".")));
122 
123  if (RmgrTable[rmid].rm_name != NULL)
124  ereport(ERROR,
125  (errmsg("failed to register custom resource manager \"%s\" with ID %d", rmgr->rm_name, rmid),
126  errdetail("Custom resource manager \"%s\" already registered with the same ID.",
127  RmgrTable[rmid].rm_name)));
128 
129  /* check for existing rmgr with the same name */
130  for (int existing_rmid = 0; existing_rmid <= RM_MAX_ID; existing_rmid++)
131  {
132  if (!RmgrIdExists(existing_rmid))
133  continue;
134 
135  if (!pg_strcasecmp(RmgrTable[existing_rmid].rm_name, rmgr->rm_name))
136  ereport(ERROR,
137  (errmsg("failed to register custom resource manager \"%s\" with ID %d", rmgr->rm_name, rmid),
138  errdetail("Existing resource manager with ID %d has the same name.", existing_rmid)));
139  }
140 
141  /* register it */
142  RmgrTable[rmid] = *rmgr;
143  ereport(LOG,
144  (errmsg("registered custom resource manager \"%s\" with ID %d",
145  rmgr->rm_name, rmid)));
146 }
147 
148 /* SQL SRF showing loaded resource managers */
149 Datum
151 {
152 #define PG_GET_RESOURCE_MANAGERS_COLS 3
153  ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
155  bool nulls[PG_GET_RESOURCE_MANAGERS_COLS] = {0};
156 
157  InitMaterializedSRF(fcinfo, 0);
158 
159  for (int rmid = 0; rmid <= RM_MAX_ID; rmid++)
160  {
161  if (!RmgrIdExists(rmid))
162  continue;
163  values[0] = Int32GetDatum(rmid);
164  values[1] = CStringGetTextDatum(GetRmgr(rmid).rm_name);
165  values[2] = BoolGetDatum(RmgrIdIsBuiltin(rmid));
166  tuplestore_putvalues(rsinfo->setResult, rsinfo->setDesc, values, nulls);
167  }
168 
169  return (Datum) 0;
170 }
static Datum values[MAXATTR]
Definition: bootstrap.c:152
#define CStringGetTextDatum(s)
Definition: builtins.h:97
int errdetail(const char *fmt,...)
Definition: elog.c:1203
int errhint(const char *fmt,...)
Definition: elog.c:1317
int errmsg(const char *fmt,...)
Definition: elog.c:1070
#define LOG
Definition: elog.h:31
#define ERROR
Definition: elog.h:39
#define ereport(elevel,...)
Definition: elog.h:149
#define PG_FUNCTION_ARGS
Definition: fmgr.h:193
void InitMaterializedSRF(FunctionCallInfo fcinfo, bits32 flags)
Definition: funcapi.c:76
bool process_shared_preload_libraries_in_progress
Definition: miscinit.c:1778
int pg_strcasecmp(const char *s1, const char *s2)
Definition: pgstrcasecmp.c:36
uintptr_t Datum
Definition: postgres.h:64
static Datum BoolGetDatum(bool X)
Definition: postgres.h:102
static Datum Int32GetDatum(int32 X)
Definition: postgres.h:212
void RmgrStartup(void)
Definition: rmgr.c:58
RmgrData RmgrTable[RM_MAX_ID+1]
Definition: rmgr.c:50
#define PG_GET_RESOURCE_MANAGERS_COLS
void RmgrCleanup(void)
Definition: rmgr.c:74
void RmgrNotFound(RmgrId rmid)
Definition: rmgr.c:91
Datum pg_get_wal_resource_managers(PG_FUNCTION_ARGS)
Definition: rmgr.c:150
void RegisterCustomRmgr(RmgrId rmid, const RmgrData *rmgr)
Definition: rmgr.c:107
static bool RmgrIdIsCustom(int rmid)
Definition: rmgr.h:48
#define RM_MAX_CUSTOM_ID
Definition: rmgr.h:36
#define RM_MAX_ID
Definition: rmgr.h:33
uint8 RmgrId
Definition: rmgr.h:11
static bool RmgrIdIsBuiltin(int rmid)
Definition: rmgr.h:42
#define RM_MIN_CUSTOM_ID
Definition: rmgr.h:35
void(* rm_cleanup)(void)
const char * rm_name
void(* rm_startup)(void)
void tuplestore_putvalues(Tuplestorestate *state, TupleDesc tdesc, const Datum *values, const bool *isnull)
Definition: tuplestore.c:750
static RmgrData GetRmgr(RmgrId rmid)
static bool RmgrIdExists(RmgrId rmid)