1 /*-------------------------------------------------------------------------
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().
13 * Portions Copyright (c) 1996-2013, PostgreSQL Global Development Group
14 * Portions Copyright (c) 1994, Regents of the University of California
16 * src/include/miscadmin.h
19 * some of the information in this file should be moved to other files.
21 *-------------------------------------------------------------------------
26 #include "pgtime.h" /* for pg_time_t */
29 #define PG_BACKEND_VERSIONSTR "postgres (PostgreSQL) " PG_VERSION "\n"
31 #define InvalidPid (-1)
34 /*****************************************************************************
35 * System interrupt and critical section handling
37 * There are two types of interrupts that a running backend needs to accept
38 * without messing up its state: QueryCancel (SIGINT) and ProcDie (SIGTERM).
39 * In both cases, we need to be able to clean up the current transaction
40 * gracefully, so we can't respond to the interrupt instantaneously ---
41 * there's no guarantee that internal data structures would be self-consistent
42 * if the code is interrupted at an arbitrary instant. Instead, the signal
43 * handlers set flags that are checked periodically during execution.
45 * The CHECK_FOR_INTERRUPTS() macro is called at strategically located spots
46 * where it is normally safe to accept a cancel or die interrupt. In some
47 * cases, we invoke CHECK_FOR_INTERRUPTS() inside low-level subroutines that
48 * might sometimes be called in contexts that do *not* want to allow a cancel
49 * or die interrupt. The HOLD_INTERRUPTS() and RESUME_INTERRUPTS() macros
50 * allow code to ensure that no cancel or die interrupt will be accepted,
51 * even if CHECK_FOR_INTERRUPTS() gets called in a subroutine. The interrupt
52 * will be held off until CHECK_FOR_INTERRUPTS() is done outside any
53 * HOLD_INTERRUPTS() ... RESUME_INTERRUPTS() section.
55 * Special mechanisms are used to let an interrupt be accepted when we are
56 * waiting for a lock or when we are waiting for command input (but, of
57 * course, only if the interrupt holdoff counter is zero). See the
58 * related code for details.
60 * A lost connection is handled similarly, although the loss of connection
61 * does not raise a signal, but is detected when we fail to write to the
62 * socket. If there was a signal for a broken connection, we could make use of
63 * it by setting ClientConnectionLost in the signal handler.
65 * A related, but conceptually distinct, mechanism is the "critical section"
66 * mechanism. A critical section not only holds off cancel/die interrupts,
67 * but causes any ereport(ERROR) or ereport(FATAL) to become ereport(PANIC)
68 * --- that is, a system-wide reset is forced. Needless to say, only really
69 * *critical* code should be marked as a critical section! Currently, this
70 * mechanism is only used for XLOG-related code.
72 *****************************************************************************/
75 /* these are marked volatile because they are set by signal handlers: */
76 extern PGDLLIMPORT volatile bool InterruptPending;
77 extern volatile bool QueryCancelPending;
78 extern volatile bool ProcDiePending;
80 extern volatile bool ClientConnectionLost;
82 /* these are marked volatile because they are examined by signal handlers: */
83 extern volatile bool ImmediateInterruptOK;
84 extern PGDLLIMPORT volatile uint32 InterruptHoldoffCount;
85 extern PGDLLIMPORT volatile uint32 CritSectionCount;
87 /* in tcop/postgres.c */
88 extern void ProcessInterrupts(void);
92 #define CHECK_FOR_INTERRUPTS() \
94 if (InterruptPending) \
95 ProcessInterrupts(); \
99 #define CHECK_FOR_INTERRUPTS() \
101 if (UNBLOCKED_SIGNAL_QUEUE()) \
102 pgwin32_dispatch_queued_signals(); \
103 if (InterruptPending) \
104 ProcessInterrupts(); \
109 #define HOLD_INTERRUPTS() (InterruptHoldoffCount++)
111 #define RESUME_INTERRUPTS() \
113 Assert(InterruptHoldoffCount > 0); \
114 InterruptHoldoffCount--; \
117 #define START_CRIT_SECTION() (CritSectionCount++)
119 #define END_CRIT_SECTION() \
121 Assert(CritSectionCount > 0); \
122 CritSectionCount--; \
126 /*****************************************************************************
128 *****************************************************************************/
131 * from utils/init/globals.c
133 extern pid_t PostmasterPid;
134 extern bool IsPostmasterEnvironment;
135 extern PGDLLIMPORT bool IsUnderPostmaster;
136 extern bool IsBackgroundWorker;
137 extern bool IsBinaryUpgrade;
139 extern bool ExitOnAnyError;
141 extern PGDLLIMPORT char *DataDir;
143 extern PGDLLIMPORT int NBuffers;
144 extern int MaxBackends;
145 extern int MaxConnections;
146 extern int max_worker_processes;
148 extern PGDLLIMPORT int MyProcPid;
149 extern PGDLLIMPORT pg_time_t MyStartTime;
150 extern PGDLLIMPORT struct Port *MyProcPort;
151 extern long MyCancelKey;
152 extern int MyPMChildSlot;
154 extern char OutputFileName[];
155 extern PGDLLIMPORT char my_exec_path[];
156 extern char pkglib_path[];
159 extern char postgres_exec_path[];
163 * done in storage/backendid.h for now.
165 * extern BackendId MyBackendId;
167 extern PGDLLIMPORT Oid MyDatabaseId;
169 extern PGDLLIMPORT Oid MyDatabaseTableSpace;
172 * Date/Time Configuration
174 * DateStyle defines the output formatting choice for date/time types:
175 * USE_POSTGRES_DATES specifies traditional Postgres format
176 * USE_ISO_DATES specifies ISO-compliant format
177 * USE_SQL_DATES specifies Oracle/Ingres-compliant format
178 * USE_GERMAN_DATES specifies German-style dd.mm/yyyy
180 * DateOrder defines the field order to be assumed when reading an
181 * ambiguous date (anything not in YYYY-MM-DD format, with a four-digit
182 * year field first, is taken to be ambiguous):
183 * DATEORDER_YMD specifies field order yy-mm-dd
184 * DATEORDER_DMY specifies field order dd-mm-yy ("European" convention)
185 * DATEORDER_MDY specifies field order mm-dd-yy ("US" convention)
187 * In the Postgres and SQL DateStyles, DateOrder also selects output field
188 * order: day comes before month in DMY style, else month comes before day.
190 * The user-visible "DateStyle" run-time parameter subsumes both of these.
193 /* valid DateStyle values */
194 #define USE_POSTGRES_DATES 0
195 #define USE_ISO_DATES 1
196 #define USE_SQL_DATES 2
197 #define USE_GERMAN_DATES 3
198 #define USE_XSD_DATES 4
200 /* valid DateOrder values */
201 #define DATEORDER_YMD 0
202 #define DATEORDER_DMY 1
203 #define DATEORDER_MDY 2
205 extern int DateStyle;
206 extern int DateOrder;
210 * INTSTYLE_POSTGRES Like Postgres < 8.4 when DateStyle = 'iso'
211 * INTSTYLE_POSTGRES_VERBOSE Like Postgres < 8.4 when DateStyle != 'iso'
212 * INTSTYLE_SQL_STANDARD SQL standard interval literals
213 * INTSTYLE_ISO_8601 ISO-8601-basic formatted intervals
215 #define INTSTYLE_POSTGRES 0
216 #define INTSTYLE_POSTGRES_VERBOSE 1
217 #define INTSTYLE_SQL_STANDARD 2
218 #define INTSTYLE_ISO_8601 3
220 extern int IntervalStyle;
223 * HasCTZSet is true if user has set timezone as a numeric offset from UTC.
224 * If so, CTimeZone is the timezone offset in seconds (using the Unix-ish
225 * sign convention, ie, positive offset is west of UTC, rather than the
226 * SQL-ish convention that positive is east of UTC).
228 extern bool HasCTZSet;
229 extern int CTimeZone;
231 #define MAXTZLEN 10 /* max TZ name len, not counting tr. null */
233 extern bool enableFsync;
234 extern bool allowSystemTableMods;
235 extern PGDLLIMPORT int work_mem;
236 extern PGDLLIMPORT int maintenance_work_mem;
238 extern int VacuumCostPageHit;
239 extern int VacuumCostPageMiss;
240 extern int VacuumCostPageDirty;
241 extern int VacuumCostLimit;
242 extern int VacuumCostDelay;
244 extern int VacuumPageHit;
245 extern int VacuumPageMiss;
246 extern int VacuumPageDirty;
248 extern int VacuumCostBalance;
249 extern bool VacuumCostActive;
252 /* in tcop/postgres.c */
254 #if defined(__ia64__) || defined(__ia64)
257 char *stack_base_ptr;
258 char *register_stack_base_ptr;
261 typedef char *pg_stack_base_t;
264 extern pg_stack_base_t set_stack_base(void);
265 extern void restore_stack_base(pg_stack_base_t base);
266 extern void check_stack_depth(void);
268 /* in tcop/utility.c */
269 extern void PreventCommandIfReadOnly(const char *cmdname);
270 extern void PreventCommandDuringRecovery(const char *cmdname);
272 /* in utils/misc/guc.c */
273 extern int trace_recovery_messages;
274 extern int trace_recovery(int trace_level);
276 /*****************************************************************************
278 * POSTGRES directory path definitions. *
279 *****************************************************************************/
281 /* flags to be OR'd to form sec_context */
282 #define SECURITY_LOCAL_USERID_CHANGE 0x0001
283 #define SECURITY_RESTRICTED_OPERATION 0x0002
285 extern char *DatabasePath;
287 /* now in utils/init/miscinit.c */
288 extern void SetDatabasePath(const char *path);
290 extern char *GetUserNameFromId(Oid roleid);
291 extern Oid GetUserId(void);
292 extern Oid GetOuterUserId(void);
293 extern Oid GetSessionUserId(void);
294 extern void GetUserIdAndSecContext(Oid *userid, int *sec_context);
295 extern void SetUserIdAndSecContext(Oid userid, int sec_context);
296 extern bool InLocalUserIdChange(void);
297 extern bool InSecurityRestrictedOperation(void);
298 extern void GetUserIdAndContext(Oid *userid, bool *sec_def_context);
299 extern void SetUserIdAndContext(Oid userid, bool sec_def_context);
300 extern void InitializeSessionUserId(const char *rolename);
301 extern void InitializeSessionUserIdStandalone(void);
302 extern void SetSessionAuthorization(Oid userid, bool is_superuser);
303 extern Oid GetCurrentRoleId(void);
304 extern void SetCurrentRoleId(Oid roleid, bool is_superuser);
306 extern void SetDataDir(const char *dir);
307 extern void ChangeToDataDir(void);
308 extern char *make_absolute_path(const char *path);
310 /* in utils/misc/superuser.c */
311 extern bool superuser(void); /* current user is superuser */
312 extern bool superuser_arg(Oid roleid); /* given user is superuser */
315 /*****************************************************************************
317 * POSTGRES processing mode definitions. *
318 *****************************************************************************/
322 * There are three processing modes in POSTGRES. They are
323 * BootstrapProcessing or "bootstrap," InitProcessing or
324 * "initialization," and NormalProcessing or "normal."
326 * The first two processing modes are used during special times. When the
327 * system state indicates bootstrap processing, transactions are all given
328 * transaction id "one" and are consequently guaranteed to commit. This mode
329 * is used during the initial generation of template databases.
331 * Initialization mode: used while starting a backend, until all normal
332 * initialization is complete. Some code behaves differently when executed
333 * in this mode to enable system bootstrapping.
335 * If a POSTGRES backend process is in normal mode, then all code may be
339 typedef enum ProcessingMode
341 BootstrapProcessing, /* bootstrap creation of template database */
342 InitProcessing, /* initializing system */
343 NormalProcessing /* normal processing */
346 extern ProcessingMode Mode;
348 #define IsBootstrapProcessingMode() (Mode == BootstrapProcessing)
349 #define IsInitProcessingMode() (Mode == InitProcessing)
350 #define IsNormalProcessingMode() (Mode == NormalProcessing)
352 #define GetProcessingMode() Mode
354 #define SetProcessingMode(mode) \
356 AssertArg((mode) == BootstrapProcessing || \
357 (mode) == InitProcessing || \
358 (mode) == NormalProcessing); \
364 * Auxiliary-process type identifiers. These used to be in bootstrap.h
365 * but it seems saner to have them here, with the ProcessingMode stuff.
366 * The MyAuxProcType global is defined and set in bootstrap.c.
371 NotAnAuxProcess = -1,
380 NUM_AUXPROCTYPES /* Must be last! */
383 extern AuxProcType MyAuxProcType;
385 #define AmBootstrapProcess() (MyAuxProcType == BootstrapProcess)
386 #define AmStartupProcess() (MyAuxProcType == StartupProcess)
387 #define AmBackgroundWriterProcess() (MyAuxProcType == BgWriterProcess)
388 #define AmCheckpointerProcess() (MyAuxProcType == CheckpointerProcess)
389 #define AmWalWriterProcess() (MyAuxProcType == WalWriterProcess)
390 #define AmWalReceiverProcess() (MyAuxProcType == WalReceiverProcess)
393 /*****************************************************************************
395 * POSTGRES initialization and cleanup definitions. *
396 *****************************************************************************/
398 /* in utils/init/postinit.c */
399 extern void pg_split_opts(char **argv, int *argcp, char *optstr);
400 extern void InitializeMaxBackends(void);
401 extern void InitPostgres(const char *in_dbname, Oid dboid, const char *username,
403 extern void BaseInit(void);
405 /* in utils/init/miscinit.c */
406 extern bool IgnoreSystemIndexes;
407 extern PGDLLIMPORT bool process_shared_preload_libraries_in_progress;
408 extern char *session_preload_libraries_string;
409 extern char *shared_preload_libraries_string;
410 extern char *local_preload_libraries_string;
413 * As of 9.1, the contents of the data-directory lock file are:
416 * 1 postmaster PID (or negative of a standalone backend's PID)
417 * 2 data directory path
418 * 3 postmaster start timestamp (time_t representation)
420 * 5 first Unix socket directory path (empty if none)
421 * 6 first listen_address (IP address or "*"; empty if no TCP port)
422 * 7 shared memory key (not present on Windows)
424 * Lines 6 and up are added via AddToDataDirLockFile() after initial file
427 * The socket lock file, if used, has the same contents as lines 1-5.
429 #define LOCK_FILE_LINE_PID 1
430 #define LOCK_FILE_LINE_DATA_DIR 2
431 #define LOCK_FILE_LINE_START_TIME 3
432 #define LOCK_FILE_LINE_PORT 4
433 #define LOCK_FILE_LINE_SOCKET_DIR 5
434 #define LOCK_FILE_LINE_LISTEN_ADDR 6
435 #define LOCK_FILE_LINE_SHMEM_KEY 7
437 extern void CreateDataDirLockFile(bool amPostmaster);
438 extern void CreateSocketLockFile(const char *socketfile, bool amPostmaster,
439 const char *socketDir);
440 extern void TouchSocketLockFiles(void);
441 extern void AddToDataDirLockFile(int target_line, const char *str);
442 extern void ValidatePgVersion(const char *path);
443 extern void process_shared_preload_libraries(void);
444 extern void process_session_preload_libraries(void);
445 extern void pg_bindtextdomain(const char *domain);
446 extern bool has_rolreplication(Oid roleid);
448 /* in access/transam/xlog.c */
449 extern bool BackupInProgress(void);
450 extern void CancelBackup(void);
452 #endif /* MISCADMIN_H */