1/*-------------------------------------------------------------------------
2 *
3 * miscadmin.h
4 * This file contains general postgres administration and initialization
5 * stuff that used to be spread out between the following files:
6 * globals.h global variables
7 * pdir.h directory path crud
8 * pinit.h postgres initialization
9 * pmod.h processing modes
10 * Over time, this has also become the preferred place for widely known
11 * resource-limitation stuff, such as work_mem and check_stack_depth().
12 *
13 * Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
14 * Portions Copyright (c) 1994, Regents of the University of California
15 *
16 * src/include/miscadmin.h
17 *
18 * NOTES
19 * some of the information in this file should be moved to other files.
20 *
21 *-------------------------------------------------------------------------
22 */
23#ifndef MISCADMIN_H
24#define MISCADMIN_H
25
26#include <signal.h>
27
28#include "datatype/timestamp.h" /* for TimestampTZ */
29#include "pgtime.h" /* for pg_time_t */
30
31
32#define InvalidPid (-1)
33
34
35/*****************************************************************************
36 * System interrupt and critical section handling
37 *
38 * There are two types of interrupts that a running backend needs to accept
39 * without messing up its state: QueryCancel (SIGINT) and ProcDie (SIGTERM).
40 * In both cases, we need to be able to clean up the current transaction
41 * gracefully, so we can't respond to the interrupt instantaneously ---
42 * there's no guarantee that internal data structures would be self-consistent
43 * if the code is interrupted at an arbitrary instant. Instead, the signal
44 * handlers set flags that are checked periodically during execution.
45 *
46 * The CHECK_FOR_INTERRUPTS() macro is called at strategically located spots
47 * where it is normally safe to accept a cancel or die interrupt. In some
48 * cases, we invoke CHECK_FOR_INTERRUPTS() inside low-level subroutines that
49 * might sometimes be called in contexts that do *not* want to allow a cancel
50 * or die interrupt. The HOLD_INTERRUPTS() and RESUME_INTERRUPTS() macros
51 * allow code to ensure that no cancel or die interrupt will be accepted,
52 * even if CHECK_FOR_INTERRUPTS() gets called in a subroutine. The interrupt
53 * will be held off until CHECK_FOR_INTERRUPTS() is done outside any
54 * HOLD_INTERRUPTS() ... RESUME_INTERRUPTS() section.
55 *
56 * There is also a mechanism to prevent query cancel interrupts, while still
57 * allowing die interrupts: HOLD_CANCEL_INTERRUPTS() and
58 * RESUME_CANCEL_INTERRUPTS().
59 *
60 * Special mechanisms are used to let an interrupt be accepted when we are
61 * waiting for a lock or when we are waiting for command input (but, of
62 * course, only if the interrupt holdoff counter is zero). See the
63 * related code for details.
64 *
65 * A lost connection is handled similarly, although the loss of connection
66 * does not raise a signal, but is detected when we fail to write to the
67 * socket. If there was a signal for a broken connection, we could make use of
68 * it by setting ClientConnectionLost in the signal handler.
69 *
70 * A related, but conceptually distinct, mechanism is the "critical section"
71 * mechanism. A critical section not only holds off cancel/die interrupts,
72 * but causes any ereport(ERROR) or ereport(FATAL) to become ereport(PANIC)
73 * --- that is, a system-wide reset is forced. Needless to say, only really
74 * *critical* code should be marked as a critical section! Currently, this
75 * mechanism is only used for XLOG-related code.
76 *
77 *****************************************************************************/
78
79/* in globals.c */
80/* these are marked volatile because they are set by signal handlers: */
81extern PGDLLIMPORT volatile sig_atomic_t InterruptPending;
82extern PGDLLIMPORT volatile sig_atomic_t QueryCancelPending;
83extern PGDLLIMPORT volatile sig_atomic_t ProcDiePending;
84extern PGDLLIMPORT volatile sig_atomic_t IdleInTransactionSessionTimeoutPending;
85extern PGDLLIMPORT volatile sig_atomic_t ConfigReloadPending;
86
87extern PGDLLIMPORT volatile sig_atomic_t ClientConnectionLost;
88
89/* these are marked volatile because they are examined by signal handlers: */
90extern PGDLLIMPORT volatile uint32 InterruptHoldoffCount;
91extern PGDLLIMPORT volatile uint32 QueryCancelHoldoffCount;
92extern PGDLLIMPORT volatile uint32 CritSectionCount;
93
94/* in tcop/postgres.c */
95extern void ProcessInterrupts(void);
96
97#ifndef WIN32
98
99#define CHECK_FOR_INTERRUPTS() \
100do { \
101 if (InterruptPending) \
102 ProcessInterrupts(); \
103} while(0)
104#else /* WIN32 */
105
106#define CHECK_FOR_INTERRUPTS() \
107do { \
108 if (UNBLOCKED_SIGNAL_QUEUE()) \
109 pgwin32_dispatch_queued_signals(); \
110 if (InterruptPending) \
111 ProcessInterrupts(); \
112} while(0)
113#endif /* WIN32 */
114
115
116#define HOLD_INTERRUPTS() (InterruptHoldoffCount++)
117
118#define RESUME_INTERRUPTS() \
119do { \
120 Assert(InterruptHoldoffCount > 0); \
121 InterruptHoldoffCount--; \
122} while(0)
123
124#define HOLD_CANCEL_INTERRUPTS() (QueryCancelHoldoffCount++)
125
126#define RESUME_CANCEL_INTERRUPTS() \
127do { \
128 Assert(QueryCancelHoldoffCount > 0); \
129 QueryCancelHoldoffCount--; \
130} while(0)
131
132#define START_CRIT_SECTION() (CritSectionCount++)
133
134#define END_CRIT_SECTION() \
135do { \
136 Assert(CritSectionCount > 0); \
137 CritSectionCount--; \
138} while(0)
139
140
141/*****************************************************************************
142 * globals.h -- *
143 *****************************************************************************/
144
145/*
146 * from utils/init/globals.c
147 */
148extern PGDLLIMPORT pid_t PostmasterPid;
149extern PGDLLIMPORT bool IsPostmasterEnvironment;
150extern PGDLLIMPORT bool IsUnderPostmaster;
151extern PGDLLIMPORT bool IsBackgroundWorker;
152extern PGDLLIMPORT bool IsBinaryUpgrade;
153
154extern PGDLLIMPORT bool ExitOnAnyError;
155
156extern PGDLLIMPORT char *DataDir;
157extern PGDLLIMPORT int data_directory_mode;
158
159extern PGDLLIMPORT int NBuffers;
160extern PGDLLIMPORT int MaxBackends;
161extern PGDLLIMPORT int MaxConnections;
162extern PGDLLIMPORT int max_worker_processes;
163extern PGDLLIMPORT int max_parallel_workers;
164
165extern PGDLLIMPORT int MyProcPid;
166extern PGDLLIMPORT pg_time_t MyStartTime;
167extern PGDLLIMPORT TimestampTz MyStartTimestamp;
168extern PGDLLIMPORT struct Port *MyProcPort;
169extern PGDLLIMPORT struct Latch *MyLatch;
170extern int32 MyCancelKey;
171extern int MyPMChildSlot;
172
173extern char OutputFileName[];
174extern PGDLLIMPORT char my_exec_path[];
175extern char pkglib_path[];
176
177#ifdef EXEC_BACKEND
178extern char postgres_exec_path[];
179#endif
180
181/*
182 * done in storage/backendid.h for now.
183 *
184 * extern BackendId MyBackendId;
185 */
186extern PGDLLIMPORT Oid MyDatabaseId;
187
188extern PGDLLIMPORT Oid MyDatabaseTableSpace;
189
190/*
191 * Date/Time Configuration
192 *
193 * DateStyle defines the output formatting choice for date/time types:
194 * USE_POSTGRES_DATES specifies traditional Postgres format
195 * USE_ISO_DATES specifies ISO-compliant format
196 * USE_SQL_DATES specifies Oracle/Ingres-compliant format
197 * USE_GERMAN_DATES specifies German-style dd.mm/yyyy
198 *
199 * DateOrder defines the field order to be assumed when reading an
200 * ambiguous date (anything not in YYYY-MM-DD format, with a four-digit
201 * year field first, is taken to be ambiguous):
202 * DATEORDER_YMD specifies field order yy-mm-dd
203 * DATEORDER_DMY specifies field order dd-mm-yy ("European" convention)
204 * DATEORDER_MDY specifies field order mm-dd-yy ("US" convention)
205 *
206 * In the Postgres and SQL DateStyles, DateOrder also selects output field
207 * order: day comes before month in DMY style, else month comes before day.
208 *
209 * The user-visible "DateStyle" run-time parameter subsumes both of these.
210 */
211
212/* valid DateStyle values */
213#define USE_POSTGRES_DATES 0
214#define USE_ISO_DATES 1
215#define USE_SQL_DATES 2
216#define USE_GERMAN_DATES 3
217#define USE_XSD_DATES 4
218
219/* valid DateOrder values */
220#define DATEORDER_YMD 0
221#define DATEORDER_DMY 1
222#define DATEORDER_MDY 2
223
224extern PGDLLIMPORT int DateStyle;
225extern PGDLLIMPORT int DateOrder;
226
227/*
228 * IntervalStyles
229 * INTSTYLE_POSTGRES Like Postgres < 8.4 when DateStyle = 'iso'
230 * INTSTYLE_POSTGRES_VERBOSE Like Postgres < 8.4 when DateStyle != 'iso'
231 * INTSTYLE_SQL_STANDARD SQL standard interval literals
232 * INTSTYLE_ISO_8601 ISO-8601-basic formatted intervals
233 */
234#define INTSTYLE_POSTGRES 0
235#define INTSTYLE_POSTGRES_VERBOSE 1
236#define INTSTYLE_SQL_STANDARD 2
237#define INTSTYLE_ISO_8601 3
238
239extern PGDLLIMPORT int IntervalStyle;
240
241#define MAXTZLEN 10 /* max TZ name len, not counting tr. null */
242
243extern bool enableFsync;
244extern PGDLLIMPORT bool allowSystemTableMods;
245extern PGDLLIMPORT int work_mem;
246extern PGDLLIMPORT int maintenance_work_mem;
247extern PGDLLIMPORT int max_parallel_maintenance_workers;
248
249extern int VacuumCostPageHit;
250extern int VacuumCostPageMiss;
251extern int VacuumCostPageDirty;
252extern int VacuumCostLimit;
253extern double VacuumCostDelay;
254
255extern int VacuumPageHit;
256extern int VacuumPageMiss;
257extern int VacuumPageDirty;
258
259extern int VacuumCostBalance;
260extern bool VacuumCostActive;
261
262extern double vacuum_cleanup_index_scale_factor;
263
264
265/* in tcop/postgres.c */
266
267#if defined(__ia64__) || defined(__ia64)
268typedef struct
269{
270 char *stack_base_ptr;
271 char *register_stack_base_ptr;
272} pg_stack_base_t;
273#else
274typedef char *pg_stack_base_t;
275#endif
276
277extern pg_stack_base_t set_stack_base(void);
278extern void restore_stack_base(pg_stack_base_t base);
279extern void check_stack_depth(void);
280extern bool stack_is_too_deep(void);
281
282extern void PostgresSigHupHandler(SIGNAL_ARGS);
283
284/* in tcop/utility.c */
285extern void PreventCommandIfReadOnly(const char *cmdname);
286extern void PreventCommandIfParallelMode(const char *cmdname);
287extern void PreventCommandDuringRecovery(const char *cmdname);
288
289/* in utils/misc/guc.c */
290extern int trace_recovery_messages;
291extern int trace_recovery(int trace_level);
292
293/*****************************************************************************
294 * pdir.h -- *
295 * POSTGRES directory path definitions. *
296 *****************************************************************************/
297
298/* flags to be OR'd to form sec_context */
299#define SECURITY_LOCAL_USERID_CHANGE 0x0001
300#define SECURITY_RESTRICTED_OPERATION 0x0002
301#define SECURITY_NOFORCE_RLS 0x0004
302
303extern char *DatabasePath;
304
305/* now in utils/init/miscinit.c */
306extern void InitPostmasterChild(void);
307extern void InitStandaloneProcess(const char *argv0);
308
309extern void SetDatabasePath(const char *path);
310
311extern char *GetUserNameFromId(Oid roleid, bool noerr);
312extern Oid GetUserId(void);
313extern Oid GetOuterUserId(void);
314extern Oid GetSessionUserId(void);
315extern Oid GetAuthenticatedUserId(void);
316extern void GetUserIdAndSecContext(Oid *userid, int *sec_context);
317extern void SetUserIdAndSecContext(Oid userid, int sec_context);
318extern bool InLocalUserIdChange(void);
319extern bool InSecurityRestrictedOperation(void);
320extern bool InNoForceRLSOperation(void);
321extern void GetUserIdAndContext(Oid *userid, bool *sec_def_context);
322extern void SetUserIdAndContext(Oid userid, bool sec_def_context);
323extern void InitializeSessionUserId(const char *rolename, Oid useroid);
324extern void InitializeSessionUserIdStandalone(void);
325extern void SetSessionAuthorization(Oid userid, bool is_superuser);
326extern Oid GetCurrentRoleId(void);
327extern void SetCurrentRoleId(Oid roleid, bool is_superuser);
328
329extern void checkDataDir(void);
330extern void SetDataDir(const char *dir);
331extern void ChangeToDataDir(void);
332
333extern void SwitchToSharedLatch(void);
334extern void SwitchBackToLocalLatch(void);
335
336/* in utils/misc/superuser.c */
337extern bool superuser(void); /* current user is superuser */
338extern bool superuser_arg(Oid roleid); /* given user is superuser */
339
340
341/*****************************************************************************
342 * pmod.h -- *
343 * POSTGRES processing mode definitions. *
344 *****************************************************************************/
345
346/*
347 * Description:
348 * There are three processing modes in POSTGRES. They are
349 * BootstrapProcessing or "bootstrap," InitProcessing or
350 * "initialization," and NormalProcessing or "normal."
351 *
352 * The first two processing modes are used during special times. When the
353 * system state indicates bootstrap processing, transactions are all given
354 * transaction id "one" and are consequently guaranteed to commit. This mode
355 * is used during the initial generation of template databases.
356 *
357 * Initialization mode: used while starting a backend, until all normal
358 * initialization is complete. Some code behaves differently when executed
359 * in this mode to enable system bootstrapping.
360 *
361 * If a POSTGRES backend process is in normal mode, then all code may be
362 * executed normally.
363 */
364
365typedef enum ProcessingMode
366{
367 BootstrapProcessing, /* bootstrap creation of template database */
368 InitProcessing, /* initializing system */
369 NormalProcessing /* normal processing */
370} ProcessingMode;
371
372extern ProcessingMode Mode;
373
374#define IsBootstrapProcessingMode() (Mode == BootstrapProcessing)
375#define IsInitProcessingMode() (Mode == InitProcessing)
376#define IsNormalProcessingMode() (Mode == NormalProcessing)
377
378#define GetProcessingMode() Mode
379
380#define SetProcessingMode(mode) \
381 do { \
382 AssertArg((mode) == BootstrapProcessing || \
383 (mode) == InitProcessing || \
384 (mode) == NormalProcessing); \
385 Mode = (mode); \
386 } while(0)
387
388
389/*
390 * Auxiliary-process type identifiers. These used to be in bootstrap.h
391 * but it seems saner to have them here, with the ProcessingMode stuff.
392 * The MyAuxProcType global is defined and set in bootstrap.c.
393 */
394
395typedef enum
396{
397 NotAnAuxProcess = -1,
398 CheckerProcess = 0,
399 BootstrapProcess,
400 StartupProcess,
401 BgWriterProcess,
402 CheckpointerProcess,
403 WalWriterProcess,
404 WalReceiverProcess,
405
406 NUM_AUXPROCTYPES /* Must be last! */
407} AuxProcType;
408
409extern AuxProcType MyAuxProcType;
410
411#define AmBootstrapProcess() (MyAuxProcType == BootstrapProcess)
412#define AmStartupProcess() (MyAuxProcType == StartupProcess)
413#define AmBackgroundWriterProcess() (MyAuxProcType == BgWriterProcess)
414#define AmCheckpointerProcess() (MyAuxProcType == CheckpointerProcess)
415#define AmWalWriterProcess() (MyAuxProcType == WalWriterProcess)
416#define AmWalReceiverProcess() (MyAuxProcType == WalReceiverProcess)
417
418
419/*****************************************************************************
420 * pinit.h -- *
421 * POSTGRES initialization and cleanup definitions. *
422 *****************************************************************************/
423
424/* in utils/init/postinit.c */
425extern void pg_split_opts(char **argv, int *argcp, const char *optstr);
426extern void InitializeMaxBackends(void);
427extern void InitPostgres(const char *in_dbname, Oid dboid, const char *username,
428 Oid useroid, char *out_dbname, bool override_allow_connections);
429extern void BaseInit(void);
430
431/* in utils/init/miscinit.c */
432extern bool IgnoreSystemIndexes;
433extern PGDLLIMPORT bool process_shared_preload_libraries_in_progress;
434extern char *session_preload_libraries_string;
435extern char *shared_preload_libraries_string;
436extern char *local_preload_libraries_string;
437
438extern void CreateDataDirLockFile(bool amPostmaster);
439extern void CreateSocketLockFile(const char *socketfile, bool amPostmaster,
440 const char *socketDir);
441extern void TouchSocketLockFiles(void);
442extern void AddToDataDirLockFile(int target_line, const char *str);
443extern bool RecheckDataDirLockFile(void);
444extern void ValidatePgVersion(const char *path);
445extern void process_shared_preload_libraries(void);
446extern void process_session_preload_libraries(void);
447extern void pg_bindtextdomain(const char *domain);
448extern bool has_rolreplication(Oid roleid);
449
450/* in access/transam/xlog.c */
451extern bool BackupInProgress(void);
452extern void CancelBackup(void);
453
454#endif /* MISCADMIN_H */
455