Header And Logo
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#include "postgres.h"#include <sys/file.h>#include <signal.h>#include <dirent.h>#include <math.h>#include <unistd.h>#include "catalog/catalog.h"#include "catalog/pg_tablespace.h"#include "catalog/pg_type.h"#include "commands/dbcommands.h"#include "common/relpath.h"#include "funcapi.h"#include "miscadmin.h"#include "parser/keywords.h"#include "postmaster/syslogger.h"#include "rewrite/rewriteHandler.h"#include "storage/fd.h"#include "storage/pmsignal.h"#include "storage/proc.h"#include "storage/procarray.h"#include "utils/lsyscache.h"#include "tcop/tcopprot.h"#include "utils/builtins.h"#include "utils/timestamp.h"
Go to the source code of this file.
Data Structures | |
| struct | ts_db_fctx |
Defines | |
| #define | atooid(x) ((Oid) strtoul((x), NULL, 10)) |
| #define | SIGNAL_BACKEND_SUCCESS 0 |
| #define | SIGNAL_BACKEND_ERROR 1 |
| #define | SIGNAL_BACKEND_NOPERMISSION 2 |
| #define | GetNowFloat() GetCurrentTimestamp() |
Functions | |
| Datum | current_database (PG_FUNCTION_ARGS) |
| Datum | current_query (PG_FUNCTION_ARGS) |
| static int | pg_signal_backend (int pid, int sig) |
| Datum | pg_cancel_backend (PG_FUNCTION_ARGS) |
| Datum | pg_terminate_backend (PG_FUNCTION_ARGS) |
| Datum | pg_reload_conf (PG_FUNCTION_ARGS) |
| Datum | pg_rotate_logfile (PG_FUNCTION_ARGS) |
| Datum | pg_tablespace_databases (PG_FUNCTION_ARGS) |
| Datum | pg_tablespace_location (PG_FUNCTION_ARGS) |
| Datum | pg_sleep (PG_FUNCTION_ARGS) |
| Datum | pg_get_keywords (PG_FUNCTION_ARGS) |
| Datum | pg_typeof (PG_FUNCTION_ARGS) |
| Datum | pg_collation_for (PG_FUNCTION_ARGS) |
| Datum | pg_view_is_insertable (PG_FUNCTION_ARGS) |
| Datum | pg_view_is_updatable (PG_FUNCTION_ARGS) |
| #define atooid | ( | x | ) | ((Oid) strtoul((x), NULL, 10)) |
Definition at line 42 of file misc.c.
Referenced by pg_tablespace_databases().
| #define GetNowFloat | ( | ) | GetCurrentTimestamp() |
Referenced by pg_sleep().
| #define SIGNAL_BACKEND_NOPERMISSION 2 |
Definition at line 90 of file misc.c.
Referenced by pg_cancel_backend(), and pg_terminate_backend().
| #define SIGNAL_BACKEND_SUCCESS 0 |
Definition at line 88 of file misc.c.
Referenced by pg_cancel_backend(), and pg_terminate_backend().
| Datum current_database | ( | PG_FUNCTION_ARGS | ) |
Definition at line 50 of file misc.c.
References get_database_name(), MyDatabaseId, NAMEDATALEN, namestrcpy(), palloc(), and PG_RETURN_NAME.
{
Name db;
db = (Name) palloc(NAMEDATALEN);
namestrcpy(db, get_database_name(MyDatabaseId));
PG_RETURN_NAME(db);
}
| Datum current_query | ( | PG_FUNCTION_ARGS | ) |
Definition at line 67 of file misc.c.
References cstring_to_text(), debug_query_string, PG_RETURN_NULL, and PG_RETURN_TEXT_P.
Referenced by dblink_current_query().
{
/* there is no easy way to access the more concise 'query_string' */
if (debug_query_string)
PG_RETURN_TEXT_P(cstring_to_text(debug_query_string));
else
PG_RETURN_NULL();
}
| Datum pg_cancel_backend | ( | PG_FUNCTION_ARGS | ) |
Definition at line 147 of file misc.c.
References ereport, errcode(), errmsg(), ERROR, PG_GETARG_INT32, PG_RETURN_BOOL, pg_signal_backend(), SIGNAL_BACKEND_NOPERMISSION, and SIGNAL_BACKEND_SUCCESS.
{
int r = pg_signal_backend(PG_GETARG_INT32(0), SIGINT);
if (r == SIGNAL_BACKEND_NOPERMISSION)
ereport(ERROR,
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
(errmsg("must be superuser or have the same role to cancel queries running in other server processes"))));
PG_RETURN_BOOL(r == SIGNAL_BACKEND_SUCCESS);
}
| Datum pg_collation_for | ( | PG_FUNCTION_ARGS | ) |
Definition at line 509 of file misc.c.
References cstring_to_text(), ereport, errcode(), errmsg(), ERROR, format_type_be(), generate_collation_name(), get_fn_expr_argtype(), PG_GET_COLLATION, PG_RETURN_NULL, PG_RETURN_TEXT_P, type_is_collatable(), and UNKNOWNOID.
{
Oid typeid;
Oid collid;
typeid = get_fn_expr_argtype(fcinfo->flinfo, 0);
if (!typeid)
PG_RETURN_NULL();
if (!type_is_collatable(typeid) && typeid != UNKNOWNOID)
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
errmsg("collations are not supported by type %s",
format_type_be(typeid))));
collid = PG_GET_COLLATION();
if (!collid)
PG_RETURN_NULL();
PG_RETURN_TEXT_P(cstring_to_text(generate_collation_name(collid)));
}
| Datum pg_get_keywords | ( | PG_FUNCTION_ARGS | ) |
Definition at line 426 of file misc.c.
References _, FuncCallContext::attinmeta, BuildTupleFromCStrings(), FuncCallContext::call_cntr, ScanKeyword::category, CHAROID, COL_NAME_KEYWORD, CreateTemplateTupleDesc(), HeapTupleGetDatum, MemoryContextSwitchTo(), FuncCallContext::multi_call_memory_ctx, ScanKeyword::name, NumScanKeywords, RESERVED_KEYWORD, ScanKeywords, SRF_FIRSTCALL_INIT, SRF_IS_FIRSTCALL, SRF_PERCALL_SETUP, SRF_RETURN_DONE, SRF_RETURN_NEXT, TEXTOID, TupleDescGetAttInMetadata(), TupleDescInitEntry(), TYPE_FUNC_NAME_KEYWORD, UNRESERVED_KEYWORD, and values.
{
FuncCallContext *funcctx;
if (SRF_IS_FIRSTCALL())
{
MemoryContext oldcontext;
TupleDesc tupdesc;
funcctx = SRF_FIRSTCALL_INIT();
oldcontext = MemoryContextSwitchTo(funcctx->multi_call_memory_ctx);
tupdesc = CreateTemplateTupleDesc(3, false);
TupleDescInitEntry(tupdesc, (AttrNumber) 1, "word",
TEXTOID, -1, 0);
TupleDescInitEntry(tupdesc, (AttrNumber) 2, "catcode",
CHAROID, -1, 0);
TupleDescInitEntry(tupdesc, (AttrNumber) 3, "catdesc",
TEXTOID, -1, 0);
funcctx->attinmeta = TupleDescGetAttInMetadata(tupdesc);
MemoryContextSwitchTo(oldcontext);
}
funcctx = SRF_PERCALL_SETUP();
if (funcctx->call_cntr < NumScanKeywords)
{
char *values[3];
HeapTuple tuple;
/* cast-away-const is ugly but alternatives aren't much better */
values[0] = (char *) ScanKeywords[funcctx->call_cntr].name;
switch (ScanKeywords[funcctx->call_cntr].category)
{
case UNRESERVED_KEYWORD:
values[1] = "U";
values[2] = _("unreserved");
break;
case COL_NAME_KEYWORD:
values[1] = "C";
values[2] = _("unreserved (cannot be function or type name)");
break;
case TYPE_FUNC_NAME_KEYWORD:
values[1] = "T";
values[2] = _("reserved (can be function or type name)");
break;
case RESERVED_KEYWORD:
values[1] = "R";
values[2] = _("reserved");
break;
default: /* shouldn't be possible */
values[1] = NULL;
values[2] = NULL;
break;
}
tuple = BuildTupleFromCStrings(funcctx->attinmeta, values);
SRF_RETURN_NEXT(funcctx, HeapTupleGetDatum(tuple));
}
SRF_RETURN_DONE(funcctx);
}
| Datum pg_reload_conf | ( | PG_FUNCTION_ARGS | ) |
Definition at line 180 of file misc.c.
References ereport, errcode(), errmsg(), ERROR, PG_RETURN_BOOL, PostmasterPid, SIGHUP, superuser(), and WARNING.
{
if (!superuser())
ereport(ERROR,
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
(errmsg("must be superuser to signal the postmaster"))));
if (kill(PostmasterPid, SIGHUP))
{
ereport(WARNING,
(errmsg("failed to send signal to postmaster: %m")));
PG_RETURN_BOOL(false);
}
PG_RETURN_BOOL(true);
}
| Datum pg_rotate_logfile | ( | PG_FUNCTION_ARGS | ) |
Definition at line 202 of file misc.c.
References ereport, errcode(), errmsg(), ERROR, Logging_collector, PG_RETURN_BOOL, PMSIGNAL_ROTATE_LOGFILE, SendPostmasterSignal(), superuser(), and WARNING.
{
if (!superuser())
ereport(ERROR,
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
(errmsg("must be superuser to rotate log files"))));
if (!Logging_collector)
{
ereport(WARNING,
(errmsg("rotation not possible because log collection not active")));
PG_RETURN_BOOL(false);
}
SendPostmasterSignal(PMSIGNAL_ROTATE_LOGFILE);
PG_RETURN_BOOL(true);
}
| static int pg_signal_backend | ( | int | pid, | |
| int | sig | |||
| ) | [static] |
Definition at line 92 of file misc.c.
References BackendPidGetProc(), ereport, errmsg(), GetUserId(), NULL, PGPROC::roleId, superuser(), and WARNING.
Referenced by pg_cancel_backend(), and pg_terminate_backend().
{
PGPROC *proc = BackendPidGetProc(pid);
/*
* BackendPidGetProc returns NULL if the pid isn't valid; but by the time
* we reach kill(), a process for which we get a valid proc here might have
* terminated on its own. There's no way to acquire a lock on an arbitrary
* process to prevent that. But since so far all the callers of this
* mechanism involve some request for ending the process anyway, that it
* might end on its own first is not a problem.
*/
if (proc == NULL)
{
/*
* This is just a warning so a loop-through-resultset will not abort
* if one backend terminated on its own during the run.
*/
ereport(WARNING,
(errmsg("PID %d is not a PostgreSQL server process", pid)));
return SIGNAL_BACKEND_ERROR;
}
if (!(superuser() || proc->roleId == GetUserId()))
return SIGNAL_BACKEND_NOPERMISSION;
/*
* Can the process we just validated above end, followed by the pid being
* recycled for a new process, before reaching here? Then we'd be trying
* to kill the wrong thing. Seems near impossible when sequential pid
* assignment and wraparound is used. Perhaps it could happen on a system
* where pid re-use is randomized. That race condition possibility seems
* too unlikely to worry about.
*/
/* If we have setsid(), signal the backend's whole process group */
#ifdef HAVE_SETSID
if (kill(-pid, sig))
#else
if (kill(pid, sig))
#endif
{
/* Again, just a warning to allow loops */
ereport(WARNING,
(errmsg("could not send signal to process %d: %m", pid)));
return SIGNAL_BACKEND_ERROR;
}
return SIGNAL_BACKEND_SUCCESS;
}
| Datum pg_sleep | ( | PG_FUNCTION_ARGS | ) |
Definition at line 381 of file misc.c.
References CHECK_FOR_INTERRUPTS, GetNowFloat, PG_GETARG_FLOAT8, PG_RETURN_VOID, and pg_usleep().
{
float8 secs = PG_GETARG_FLOAT8(0);
float8 endtime;
/*
* We break the requested sleep into segments of no more than 1 second, to
* put an upper bound on how long it will take us to respond to a cancel
* or die interrupt. (Note that pg_usleep is interruptible by signals on
* some platforms but not others.) Also, this method avoids exposing
* pg_usleep's upper bound on allowed delays.
*
* By computing the intended stop time initially, we avoid accumulation of
* extra delay across multiple sleeps. This also ensures we won't delay
* less than the specified time if pg_usleep is interrupted by other
* signals such as SIGHUP.
*/
#ifdef HAVE_INT64_TIMESTAMP
#define GetNowFloat() ((float8) GetCurrentTimestamp() / 1000000.0)
#else
#define GetNowFloat() GetCurrentTimestamp()
#endif
endtime = GetNowFloat() + secs;
for (;;)
{
float8 delay;
CHECK_FOR_INTERRUPTS();
delay = endtime - GetNowFloat();
if (delay >= 1.0)
pg_usleep(1000000L);
else if (delay > 0.0)
pg_usleep((long) ceil(delay * 1000000.0));
else
break;
}
PG_RETURN_VOID();
}
| Datum pg_tablespace_databases | ( | PG_FUNCTION_ARGS | ) |
Definition at line 229 of file misc.c.
References AllocateDir(), atooid, dirent::d_name, DEFAULTTABLESPACE_OID, ts_db_fctx::dirdesc, ereport, errcode_for_file_access(), errmsg(), ERROR, FreeDir(), GLOBALTABLESPACE_OID, ts_db_fctx::location, MemoryContextSwitchTo(), FuncCallContext::multi_call_memory_ctx, NULL, ObjectIdGetDatum, OIDCHARS, palloc(), pfree(), PG_GETARG_OID, ReadDir(), SRF_FIRSTCALL_INIT, SRF_IS_FIRSTCALL, SRF_PERCALL_SETUP, SRF_RETURN_DONE, SRF_RETURN_NEXT, TABLESPACE_VERSION_DIRECTORY, FuncCallContext::user_fctx, and WARNING.
{
FuncCallContext *funcctx;
struct dirent *de;
ts_db_fctx *fctx;
if (SRF_IS_FIRSTCALL())
{
MemoryContext oldcontext;
Oid tablespaceOid = PG_GETARG_OID(0);
funcctx = SRF_FIRSTCALL_INIT();
oldcontext = MemoryContextSwitchTo(funcctx->multi_call_memory_ctx);
fctx = palloc(sizeof(ts_db_fctx));
/*
* size = tablespace dirname length + dir sep char + oid + terminator
*/
fctx->location = (char *) palloc(9 + 1 + OIDCHARS + 1 +
strlen(TABLESPACE_VERSION_DIRECTORY) + 1);
if (tablespaceOid == GLOBALTABLESPACE_OID)
{
fctx->dirdesc = NULL;
ereport(WARNING,
(errmsg("global tablespace never has databases")));
}
else
{
if (tablespaceOid == DEFAULTTABLESPACE_OID)
sprintf(fctx->location, "base");
else
sprintf(fctx->location, "pg_tblspc/%u/%s", tablespaceOid,
TABLESPACE_VERSION_DIRECTORY);
fctx->dirdesc = AllocateDir(fctx->location);
if (!fctx->dirdesc)
{
/* the only expected error is ENOENT */
if (errno != ENOENT)
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not open directory \"%s\": %m",
fctx->location)));
ereport(WARNING,
(errmsg("%u is not a tablespace OID", tablespaceOid)));
}
}
funcctx->user_fctx = fctx;
MemoryContextSwitchTo(oldcontext);
}
funcctx = SRF_PERCALL_SETUP();
fctx = (ts_db_fctx *) funcctx->user_fctx;
if (!fctx->dirdesc) /* not a tablespace */
SRF_RETURN_DONE(funcctx);
while ((de = ReadDir(fctx->dirdesc, fctx->location)) != NULL)
{
char *subdir;
DIR *dirdesc;
Oid datOid = atooid(de->d_name);
/* this test skips . and .., but is awfully weak */
if (!datOid)
continue;
/* if database subdir is empty, don't report tablespace as used */
/* size = path length + dir sep char + file name + terminator */
subdir = palloc(strlen(fctx->location) + 1 + strlen(de->d_name) + 1);
sprintf(subdir, "%s/%s", fctx->location, de->d_name);
dirdesc = AllocateDir(subdir);
while ((de = ReadDir(dirdesc, subdir)) != NULL)
{
if (strcmp(de->d_name, ".") != 0 && strcmp(de->d_name, "..") != 0)
break;
}
FreeDir(dirdesc);
pfree(subdir);
if (!de)
continue; /* indeed, nothing in it */
SRF_RETURN_NEXT(funcctx, ObjectIdGetDatum(datOid));
}
FreeDir(fctx->dirdesc);
SRF_RETURN_DONE(funcctx);
}
| Datum pg_tablespace_location | ( | PG_FUNCTION_ARGS | ) |
Definition at line 327 of file misc.c.
References cstring_to_text(), DEFAULTTABLESPACE_OID, ereport, errcode(), errmsg(), ERROR, GLOBALTABLESPACE_OID, InvalidOid, MyDatabaseTableSpace, PG_GETARG_OID, PG_RETURN_NULL, PG_RETURN_TEXT_P, and snprintf().
{
Oid tablespaceOid = PG_GETARG_OID(0);
char sourcepath[MAXPGPATH];
char targetpath[MAXPGPATH];
int rllen;
/*
* It's useful to apply this function to pg_class.reltablespace, wherein
* zero means "the database's default tablespace". So, rather than
* throwing an error for zero, we choose to assume that's what is meant.
*/
if (tablespaceOid == InvalidOid)
tablespaceOid = MyDatabaseTableSpace;
/*
* Return empty string for the cluster's default tablespaces
*/
if (tablespaceOid == DEFAULTTABLESPACE_OID ||
tablespaceOid == GLOBALTABLESPACE_OID)
PG_RETURN_TEXT_P(cstring_to_text(""));
#if defined(HAVE_READLINK) || defined(WIN32)
/*
* Find the location of the tablespace by reading the symbolic link that
* is in pg_tblspc/<oid>.
*/
snprintf(sourcepath, sizeof(sourcepath), "pg_tblspc/%u", tablespaceOid);
rllen = readlink(sourcepath, targetpath, sizeof(targetpath));
if (rllen < 0)
ereport(ERROR,
(errmsg("could not read symbolic link \"%s\": %m",
sourcepath)));
else if (rllen >= sizeof(targetpath))
ereport(ERROR,
(errmsg("symbolic link \"%s\" target is too long",
sourcepath)));
targetpath[rllen] = '\0';
PG_RETURN_TEXT_P(cstring_to_text(targetpath));
#else
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("tablespaces are not supported on this platform")));
PG_RETURN_NULL();
#endif
}
| Datum pg_terminate_backend | ( | PG_FUNCTION_ARGS | ) |
Definition at line 164 of file misc.c.
References ereport, errcode(), errmsg(), ERROR, PG_GETARG_INT32, PG_RETURN_BOOL, pg_signal_backend(), SIGNAL_BACKEND_NOPERMISSION, and SIGNAL_BACKEND_SUCCESS.
{
int r = pg_signal_backend(PG_GETARG_INT32(0), SIGTERM);
if (r == SIGNAL_BACKEND_NOPERMISSION)
ereport(ERROR,
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
(errmsg("must be superuser or have the same role to terminate other server processes"))));
PG_RETURN_BOOL(r == SIGNAL_BACKEND_SUCCESS);
}
| Datum pg_typeof | ( | PG_FUNCTION_ARGS | ) |
Definition at line 498 of file misc.c.
References get_fn_expr_argtype(), and PG_RETURN_OID.
{
PG_RETURN_OID(get_fn_expr_argtype(fcinfo->flinfo, 0));
}
| Datum pg_view_is_insertable | ( | PG_FUNCTION_ARGS | ) |
Definition at line 542 of file misc.c.
References PG_GETARG_OID, PG_RETURN_BOOL, and relation_is_updatable().
{
Oid viewoid = PG_GETARG_OID(0);
int req_events = (1 << CMD_INSERT);
PG_RETURN_BOOL(relation_is_updatable(viewoid, req_events));
}
| Datum pg_view_is_updatable | ( | PG_FUNCTION_ARGS | ) |
Definition at line 551 of file misc.c.
References CMD_DELETE, PG_GETARG_OID, PG_RETURN_BOOL, and relation_is_updatable().
{
Oid viewoid = PG_GETARG_OID(0);
int req_events = (1 << CMD_UPDATE) | (1 << CMD_DELETE);
PG_RETURN_BOOL(relation_is_updatable(viewoid, req_events));
}
1.7.1