* miscinit.c
* miscellaneous initialization support stuff
*
- * Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1996-2015, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/utils/init/miscinit.c,v 1.162 2007/02/15 23:23:23 alvherre Exp $
+ * src/backend/utils/init/miscinit.c
*
*-------------------------------------------------------------------------
*/
#include <sys/param.h>
#include <signal.h>
+#include <time.h>
#include <sys/file.h>
#include <sys/stat.h>
#include <sys/time.h>
+#include <sys/types.h>
#include <fcntl.h>
#include <unistd.h>
#include <grp.h>
#include <utime.h>
#endif
+#include "access/htup_details.h"
#include "catalog/pg_authid.h"
+#include "mb/pg_wchar.h"
#include "miscadmin.h"
#include "postmaster/autovacuum.h"
+#include "postmaster/postmaster.h"
#include "storage/fd.h"
#include "storage/ipc.h"
+#include "storage/latch.h"
#include "storage/pg_shmem.h"
#include "storage/proc.h"
#include "storage/procarray.h"
#include "utils/builtins.h"
#include "utils/guc.h"
+#include "utils/memutils.h"
#include "utils/syscache.h"
ProcessingMode Mode = InitProcessing;
-/* Note: we rely on this to initialize as zeroes */
-static char socketLockFile[MAXPGPATH];
+/* List of lock files to be removed at proc exit */
+static List *lock_files = NIL;
+static Latch LocalLatchData;
/* ----------------------------------------------------------------
* ignoring system indexes support stuff
*
* NOTE: "ignoring system indexes" means we do not use the system indexes
* for lookups (either in hardwired catalog accesses or in planner-generated
- * plans). We do, however, still update the indexes when a catalog
+ * plans). We do, however, still update the indexes when a catalog
* modification is made.
* ----------------------------------------------------------------
*/
bool IgnoreSystemIndexes = false;
-/* ----------------------------------------------------------------
- * system index reindexing support
- *
- * When we are busy reindexing a system index, this code provides support
- * for preventing catalog lookups from using that index.
- * ----------------------------------------------------------------
- */
-
-static Oid currentlyReindexedHeap = InvalidOid;
-static Oid currentlyReindexedIndex = InvalidOid;
-
-/*
- * ReindexIsProcessingHeap
- * True if heap specified by OID is currently being reindexed.
- */
-bool
-ReindexIsProcessingHeap(Oid heapOid)
-{
- return heapOid == currentlyReindexedHeap;
-}
-
-/*
- * ReindexIsProcessingIndex
- * True if index specified by OID is currently being reindexed.
- */
-bool
-ReindexIsProcessingIndex(Oid indexOid)
-{
- return indexOid == currentlyReindexedIndex;
-}
-
-/*
- * SetReindexProcessing
- * Set flag that specified heap/index are being reindexed.
- */
-void
-SetReindexProcessing(Oid heapOid, Oid indexOid)
-{
- Assert(OidIsValid(heapOid) && OidIsValid(indexOid));
- /* Reindexing is not re-entrant. */
- if (OidIsValid(currentlyReindexedIndex))
- elog(ERROR, "cannot reindex while reindexing");
- currentlyReindexedHeap = heapOid;
- currentlyReindexedIndex = indexOid;
-}
-
-/*
- * ResetReindexProcessing
- * Unset reindexing status.
- */
-void
-ResetReindexProcessing(void)
-{
- currentlyReindexedHeap = InvalidOid;
- currentlyReindexedIndex = InvalidOid;
-}
/* ----------------------------------------------------------------
* database path / name support stuff
void
SetDatabasePath(const char *path)
{
- if (DatabasePath)
- {
- free(DatabasePath);
- DatabasePath = NULL;
- }
- /* use strdup since this is done before memory contexts are set up */
- if (path)
- {
- DatabasePath = strdup(path);
- AssertState(DatabasePath);
- }
+ /* This should happen only once per process */
+ Assert(!DatabasePath);
+ DatabasePath = MemoryContextStrdup(TopMemoryContext, path);
}
/*
DataDir)));
}
-/*
- * If the given pathname isn't already absolute, make it so, interpreting
- * it relative to the current working directory.
- *
- * Also canonicalizes the path. The result is always a malloc'd copy.
- *
- * Note: interpretation of relative-path arguments during postmaster startup
- * should happen before doing ChangeToDataDir(), else the user will probably
- * not like the results.
- */
-char *
-make_absolute_path(const char *path)
-{
- char *new;
-
- /* Returning null for null input is convenient for some callers */
- if (path == NULL)
- return NULL;
-
- if (!is_absolute_path(path))
- {
- char *buf;
- size_t buflen;
-
- buflen = MAXPGPATH;
- for (;;)
- {
- buf = malloc(buflen);
- if (!buf)
- ereport(FATAL,
- (errcode(ERRCODE_OUT_OF_MEMORY),
- errmsg("out of memory")));
-
- if (getcwd(buf, buflen))
- break;
- else if (errno == ERANGE)
- {
- free(buf);
- buflen *= 2;
- continue;
- }
- else
- {
- free(buf);
- elog(FATAL, "could not get current working directory: %m");
- }
- }
-
- new = malloc(strlen(buf) + strlen(path) + 2);
- if (!new)
- ereport(FATAL,
- (errcode(ERRCODE_OUT_OF_MEMORY),
- errmsg("out of memory")));
- sprintf(new, "%s/%s", buf, path);
- free(buf);
- }
- else
- {
- new = strdup(path);
- if (!new)
- ereport(FATAL,
- (errcode(ERRCODE_OUT_OF_MEMORY),
- errmsg("out of memory")));
- }
-
- /* Make sure punctuation is canonical, too */
- canonicalize_path(new);
-
- return new;
-}
-
/* ----------------------------------------------------------------
* User ID state
* OuterUserId is the current user ID in effect at the "outer level" (outside
* any transaction or function). This is initially the same as SessionUserId,
* but can be changed by SET ROLE to any role that SessionUserId is a
- * member of. We store this mainly so that AtAbort_UserId knows what to
- * reset CurrentUserId to.
+ * member of. (XXX rename to something like CurrentRoleId?)
*
* CurrentUserId is the current effective user ID; this is the one to use
* for all normal permissions-checking purposes. At outer level this will
* be the same as OuterUserId, but it changes during calls to SECURITY
* DEFINER functions, as well as locally in some specialized commands.
+ *
+ * SecurityRestrictionContext holds flags indicating reason(s) for changing
+ * CurrentUserId. In some cases we need to lock down operations that are
+ * not directly controlled by privilege settings, and this provides a
+ * convenient way to do it.
* ----------------------------------------------------------------
*/
static Oid AuthenticatedUserId = InvalidOid;
static bool AuthenticatedUserIsSuperuser = false;
static bool SessionUserIsSuperuser = false;
+static int SecurityRestrictionContext = 0;
+
/* We also remember if a SET ROLE is currently active */
static bool SetRoleIsActive = false;
+/*
+ * Initialize the basic environment for a postmaster child
+ *
+ * Should be called as early as possible after the child's startup.
+ */
+void
+InitPostmasterChild(void)
+{
+ IsUnderPostmaster = true; /* we are a postmaster subprocess now */
+
+ MyProcPid = getpid(); /* reset MyProcPid */
+
+ MyStartTime = time(NULL); /* set our start time in case we call elog */
+
+ /*
+ * make sure stderr is in binary mode before anything can possibly be
+ * written to it, in case it's actually the syslogger pipe, so the pipe
+ * chunking protocol isn't disturbed. Non-logpipe data gets translated on
+ * redirection (e.g. via pg_ctl -l) anyway.
+ */
+#ifdef WIN32
+ _setmode(fileno(stderr), _O_BINARY);
+#endif
+
+ /* We don't want the postmaster's proc_exit() handlers */
+ on_exit_reset();
+
+ /* Initialize process-local latch support */
+ InitializeLatchSupport();
+ MyLatch = &LocalLatchData;
+ InitLatch(MyLatch);
+
+ /*
+ * If possible, make this process a group leader, so that the postmaster
+ * can signal any child processes too. Not all processes will have
+ * children, but for consistency we make all postmaster child processes do
+ * this.
+ */
+#ifdef HAVE_SETSID
+ if (setsid() < 0)
+ elog(FATAL, "setsid() failed: %m");
+#endif
+}
/*
- * GetUserId/SetUserId - get/set the current effective user ID.
+ * Initialize the basic environment for a standalone process.
+ *
+ * argv0 has to be suitable to find the program's executable.
*/
-Oid
-GetUserId(void)
+void
+InitStandaloneProcess(const char *argv0)
{
- AssertState(OidIsValid(CurrentUserId));
- return CurrentUserId;
+ Assert(!IsPostmasterEnvironment);
+
+ MyProcPid = getpid(); /* reset MyProcPid */
+
+ MyStartTime = time(NULL); /* set our start time in case we call elog */
+
+ /* Initialize process-local latch support */
+ InitializeLatchSupport();
+ MyLatch = &LocalLatchData;
+ InitLatch(MyLatch);
+
+ /* Compute paths, no postmaster to inherit from */
+ if (my_exec_path[0] == '\0')
+ {
+ if (find_my_exec(argv0, my_exec_path) < 0)
+ elog(FATAL, "%s: could not locate my own executable path",
+ argv0);
+ }
+
+ if (pkglib_path[0] == '\0')
+ get_pkglib_path(my_exec_path, pkglib_path);
}
+void
+SwitchToSharedLatch(void)
+{
+ Assert(MyLatch == &LocalLatchData);
+ Assert(MyProc != NULL);
+
+ MyLatch = &MyProc->procLatch;
+
+ /*
+ * Set the shared latch as the local one might have been set. This
+ * shouldn't normally be necessary as code is supposed to check the
+ * condition before waiting for the latch, but a bit care can't hurt.
+ */
+ SetLatch(MyLatch);
+}
void
-SetUserId(Oid userid)
+SwitchBackToLocalLatch(void)
{
- AssertArg(OidIsValid(userid));
- CurrentUserId = userid;
+ Assert(MyLatch != &LocalLatchData);
+ Assert(MyProc != NULL && MyLatch == &MyProc->procLatch);
+
+ MyLatch = &LocalLatchData;
+ SetLatch(MyLatch);
+}
+
+/*
+ * GetUserId - get the current effective user ID.
+ *
+ * Note: there's no SetUserId() anymore; use SetUserIdAndSecContext().
+ */
+Oid
+GetUserId(void)
+{
+ AssertState(OidIsValid(CurrentUserId));
+ return CurrentUserId;
}
static void
SetOuterUserId(Oid userid)
{
+ AssertState(SecurityRestrictionContext == 0);
AssertArg(OidIsValid(userid));
OuterUserId = userid;
static void
SetSessionUserId(Oid userid, bool is_superuser)
{
+ AssertState(SecurityRestrictionContext == 0);
AssertArg(OidIsValid(userid));
SessionUserId = userid;
SessionUserIsSuperuser = is_superuser;
CurrentUserId = userid;
}
+/*
+ * GetAuthenticatedUserId - get the authenticated user ID
+ */
+Oid
+GetAuthenticatedUserId(void)
+{
+ AssertState(OidIsValid(AuthenticatedUserId));
+ return AuthenticatedUserId;
+}
+
+
+/*
+ * GetUserIdAndSecContext/SetUserIdAndSecContext - get/set the current user ID
+ * and the SecurityRestrictionContext flags.
+ *
+ * Currently there are three valid bits in SecurityRestrictionContext:
+ *
+ * SECURITY_LOCAL_USERID_CHANGE indicates that we are inside an operation
+ * that is temporarily changing CurrentUserId via these functions. This is
+ * needed to indicate that the actual value of CurrentUserId is not in sync
+ * with guc.c's internal state, so SET ROLE has to be disallowed.
+ *
+ * SECURITY_RESTRICTED_OPERATION indicates that we are inside an operation
+ * that does not wish to trust called user-defined functions at all. This
+ * bit prevents not only SET ROLE, but various other changes of session state
+ * that normally is unprotected but might possibly be used to subvert the
+ * calling session later. An example is replacing an existing prepared
+ * statement with new code, which will then be executed with the outer
+ * session's permissions when the prepared statement is next used. Since
+ * these restrictions are fairly draconian, we apply them only in contexts
+ * where the called functions are really supposed to be side-effect-free
+ * anyway, such as VACUUM/ANALYZE/REINDEX.
+ *
+ * SECURITY_NOFORCE_RLS indicates that we are inside an operation which should
+ * ignore the FORCE ROW LEVEL SECURITY per-table indication. This is used to
+ * ensure that FORCE RLS does not mistakenly break referential integrity
+ * checks. Note that this is intentionally only checked when running as the
+ * owner of the table (which should always be the case for referential
+ * integrity checks).
+ *
+ * Unlike GetUserId, GetUserIdAndSecContext does *not* Assert that the current
+ * value of CurrentUserId is valid; nor does SetUserIdAndSecContext require
+ * the new value to be valid. In fact, these routines had better not
+ * ever throw any kind of error. This is because they are used by
+ * StartTransaction and AbortTransaction to save/restore the settings,
+ * and during the first transaction within a backend, the value to be saved
+ * and perhaps restored is indeed invalid. We have to be able to get
+ * through AbortTransaction without asserting in case InitPostgres fails.
+ */
+void
+GetUserIdAndSecContext(Oid *userid, int *sec_context)
+{
+ *userid = CurrentUserId;
+ *sec_context = SecurityRestrictionContext;
+}
+
+void
+SetUserIdAndSecContext(Oid userid, int sec_context)
+{
+ CurrentUserId = userid;
+ SecurityRestrictionContext = sec_context;
+}
+
+
+/*
+ * InLocalUserIdChange - are we inside a local change of CurrentUserId?
+ */
+bool
+InLocalUserIdChange(void)
+{
+ return (SecurityRestrictionContext & SECURITY_LOCAL_USERID_CHANGE) != 0;
+}
+
+/*
+ * InSecurityRestrictedOperation - are we inside a security-restricted command?
+ */
+bool
+InSecurityRestrictedOperation(void)
+{
+ return (SecurityRestrictionContext & SECURITY_RESTRICTED_OPERATION) != 0;
+}
+
+/*
+ * InNoForceRLSOperation - are we ignoring FORCE ROW LEVEL SECURITY ?
+ */
+bool
+InNoForceRLSOperation(void)
+{
+ return (SecurityRestrictionContext & SECURITY_NOFORCE_RLS) != 0;
+}
+
+
+/*
+ * These are obsolete versions of Get/SetUserIdAndSecContext that are
+ * only provided for bug-compatibility with some rather dubious code in
+ * pljava. We allow the userid to be set, but only when not inside a
+ * security restriction context.
+ */
+void
+GetUserIdAndContext(Oid *userid, bool *sec_def_context)
+{
+ *userid = CurrentUserId;
+ *sec_def_context = InLocalUserIdChange();
+}
+
+void
+SetUserIdAndContext(Oid userid, bool sec_def_context)
+{
+ /* We throw the same error SET ROLE would. */
+ if (InSecurityRestrictedOperation())
+ ereport(ERROR,
+ (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
+ errmsg("cannot set parameter \"%s\" within security-restricted operation",
+ "role")));
+ CurrentUserId = userid;
+ if (sec_def_context)
+ SecurityRestrictionContext |= SECURITY_LOCAL_USERID_CHANGE;
+ else
+ SecurityRestrictionContext &= ~SECURITY_LOCAL_USERID_CHANGE;
+}
+
+
+/*
+ * Check whether specified role has explicit REPLICATION privilege
+ */
+bool
+has_rolreplication(Oid roleid)
+{
+ bool result = false;
+ HeapTuple utup;
+
+ utup = SearchSysCache1(AUTHOID, ObjectIdGetDatum(roleid));
+ if (HeapTupleIsValid(utup))
+ {
+ result = ((Form_pg_authid) GETSTRUCT(utup))->rolreplication;
+ ReleaseSysCache(utup);
+ }
+ return result;
+}
/*
* Initialize user identity during normal backend startup
*/
void
-InitializeSessionUserId(const char *rolename)
+InitializeSessionUserId(const char *rolename, Oid roleid)
{
HeapTuple roleTup;
Form_pg_authid rform;
- Datum datum;
- bool isnull;
- Oid roleid;
/*
* Don't do scans if we're bootstrapping, none of the system catalogs
/* call only once */
AssertState(!OidIsValid(AuthenticatedUserId));
- roleTup = SearchSysCache(AUTHNAME,
- PointerGetDatum(rolename),
- 0, 0, 0);
+ if (rolename != NULL)
+ roleTup = SearchSysCache1(AUTHNAME, PointerGetDatum(rolename));
+ else
+ roleTup = SearchSysCache1(AUTHOID, ObjectIdGetDatum(roleid));
if (!HeapTupleIsValid(roleTup))
ereport(FATAL,
(errcode(ERRCODE_INVALID_AUTHORIZATION_SPECIFICATION),
* These next checks are not enforced when in standalone mode, so that
* there is a way to recover from sillinesses like "UPDATE pg_authid SET
* rolcanlogin = false;".
- *
- * We do not enforce them for the autovacuum process either.
*/
- if (IsUnderPostmaster && !IsAutoVacuumWorkerProcess())
+ if (IsUnderPostmaster)
{
/*
* Is role allowed to login at all?
* Check connection limit for this role.
*
* There is a race condition here --- we create our PGPROC before
- * checking for other PGPROCs. If two backends did this at about the
+ * checking for other PGPROCs. If two backends did this at about the
* same time, they might both think they were over the limit, while
* ideally one should succeed and one fail. Getting that to work
* exactly seems more trouble than it is worth, however; instead we
AuthenticatedUserIsSuperuser ? "on" : "off",
PGC_INTERNAL, PGC_S_OVERRIDE);
- /*
- * Set up user-specific configuration variables. This is a good place to
- * do it so we don't have to read pg_authid twice during session startup.
- */
- datum = SysCacheGetAttr(AUTHNAME, roleTup,
- Anum_pg_authid_rolconfig, &isnull);
- if (!isnull)
- {
- ArrayType *a = DatumGetArrayTypeP(datum);
-
- ProcessGUCArray(a, PGC_S_USER);
- }
-
ReleaseSysCache(roleTup);
}
void
InitializeSessionUserIdStandalone(void)
{
- /* This function should only be called in a single-user backend. */
- AssertState(!IsUnderPostmaster || IsAutoVacuumWorkerProcess());
+ /*
+ * This function should only be called in single-user mode, in autovacuum
+ * workers, and in background workers.
+ */
+ AssertState(!IsUnderPostmaster || IsAutoVacuumWorkerProcess() || IsBackgroundWorker);
/* call only once */
AssertState(!OidIsValid(AuthenticatedUserId));
}
-/*
- * Reset effective userid during AbortTransaction
- *
- * This is essentially SetUserId(GetOuterUserId()), but without the Asserts.
- * The reason is that if a backend's InitPostgres transaction fails (eg,
- * because an invalid user name was given), we have to be able to get through
- * AbortTransaction without asserting.
- */
-void
-AtAbort_UserId(void)
-{
- CurrentUserId = OuterUserId;
-}
-
-
/*
* Change session auth ID while running
*
* Change Role ID while running (SET ROLE)
*
* If roleid is InvalidOid, we are doing SET ROLE NONE: revert to the
- * session user authorization. In this case the is_superuser argument
+ * session user authorization. In this case the is_superuser argument
* is ignored.
*
* When roleid is not InvalidOid, the caller must have checked whether
/*
- * Get user name from user oid
+ * Get user name from user oid, returns NULL for nonexistent roleid if noerr
+ * is true.
*/
char *
-GetUserNameFromId(Oid roleid)
+GetUserNameFromId(Oid roleid, bool noerr)
{
HeapTuple tuple;
char *result;
- tuple = SearchSysCache(AUTHOID,
- ObjectIdGetDatum(roleid),
- 0, 0, 0);
+ tuple = SearchSysCache1(AUTHOID, ObjectIdGetDatum(roleid));
if (!HeapTupleIsValid(tuple))
- ereport(ERROR,
- (errcode(ERRCODE_UNDEFINED_OBJECT),
- errmsg("invalid role OID: %u", roleid)));
-
- result = pstrdup(NameStr(((Form_pg_authid) GETSTRUCT(tuple))->rolname));
-
- ReleaseSysCache(tuple);
+ {
+ if (!noerr)
+ ereport(ERROR,
+ (errcode(ERRCODE_UNDEFINED_OBJECT),
+ errmsg("invalid role OID: %u", roleid)));
+ result = NULL;
+ }
+ else
+ {
+ result = pstrdup(NameStr(((Form_pg_authid) GETSTRUCT(tuple))->rolname));
+ ReleaseSysCache(tuple);
+ }
return result;
}
* Interlock-file support
*
* These routines are used to create both a data-directory lockfile
- * ($DATADIR/postmaster.pid) and a Unix-socket-file lockfile ($SOCKFILE.lock).
- * Both kinds of files contain the same info:
- *
- * Owning process' PID
- * Data directory path
- *
- * By convention, the owning process' PID is negated if it is a standalone
- * backend rather than a postmaster. This is just for informational purposes.
- * The path is also just for informational purposes (so that a socket lockfile
- * can be more easily traced to the associated postmaster).
- *
- * A data-directory lockfile can optionally contain a third line, containing
- * the key and ID for the shared memory block used by this postmaster.
+ * ($DATADIR/postmaster.pid) and Unix-socket-file lockfiles ($SOCKFILE.lock).
+ * Both kinds of files contain the same info initially, although we can add
+ * more information to a data-directory lockfile after it's created, using
+ * AddToDataDirLockFile(). See miscadmin.h for documentation of the contents
+ * of these lockfiles.
*
* On successful lockfile creation, a proc_exit callback to remove the
* lockfile is automatically created.
*/
/*
- * proc_exit callback to remove a lockfile.
+ * proc_exit callback to remove lockfiles.
*/
static void
-UnlinkLockFile(int status, Datum filename)
+UnlinkLockFiles(int status, Datum arg)
{
- char *fname = (char *) DatumGetPointer(filename);
+ ListCell *l;
- if (fname != NULL)
+ foreach(l, lock_files)
{
- if (unlink(fname) != 0)
- {
- /* Should we complain if the unlink fails? */
- }
- free(fname);
+ char *curfile = (char *) lfirst(l);
+
+ unlink(curfile);
+ /* Should we complain if the unlink fails? */
}
+ /* Since we're about to exit, no need to reclaim storage */
+ lock_files = NIL;
}
/*
* Create a lockfile.
*
- * filename is the name of the lockfile to create.
+ * filename is the path name of the lockfile to create.
* amPostmaster is used to determine how to encode the output PID.
+ * socketDir is the Unix socket directory path to include (possibly empty).
* isDDLock and refName are used to determine what error message to produce.
*/
static void
CreateLockFile(const char *filename, bool amPostmaster,
+ const char *socketDir,
bool isDDLock, const char *refName)
{
int fd;
- char buffer[MAXPGPATH + 100];
+ char buffer[MAXPGPATH * 2 + 256];
int ntries;
int len;
int encoded_pid;
pid_t other_pid;
- pid_t my_pid = getpid();
+ pid_t my_pid,
+ my_p_pid,
+ my_gp_pid;
+ const char *envvar;
/*
- * We need a loop here because of race conditions. But don't loop forever
+ * If the PID in the lockfile is our own PID or our parent's or
+ * grandparent's PID, then the file must be stale (probably left over from
+ * a previous system boot cycle). We need to check this because of the
+ * likelihood that a reboot will assign exactly the same PID as we had in
+ * the previous reboot, or one that's only one or two counts larger and
+ * hence the lockfile's PID now refers to an ancestor shell process. We
+ * allow pg_ctl to pass down its parent shell PID (our grandparent PID)
+ * via the environment variable PG_GRANDPARENT_PID; this is so that
+ * launching the postmaster via pg_ctl can be just as reliable as
+ * launching it directly. There is no provision for detecting
+ * further-removed ancestor processes, but if the init script is written
+ * carefully then all but the immediate parent shell will be root-owned
+ * processes and so the kill test will fail with EPERM. Note that we
+ * cannot get a false negative this way, because an existing postmaster
+ * would surely never launch a competing postmaster or pg_ctl process
+ * directly.
+ */
+ my_pid = getpid();
+
+#ifndef WIN32
+ my_p_pid = getppid();
+#else
+
+ /*
+ * Windows hasn't got getppid(), but doesn't need it since it's not using
+ * real kill() either...
+ */
+ my_p_pid = 0;
+#endif
+
+ envvar = getenv("PG_GRANDPARENT_PID");
+ if (envvar)
+ my_gp_pid = atoi(envvar);
+ else
+ my_gp_pid = 0;
+
+ /*
+ * We need a loop here because of race conditions. But don't loop forever
* (for example, a non-writable $PGDATA directory might cause a failure
* that won't go away). 100 tries seems like plenty.
*/
/*
* Try to create the lock file --- O_EXCL makes this atomic.
*
- * Think not to make the file protection weaker than 0600. See
+ * Think not to make the file protection weaker than 0600. See
* comments below.
*/
fd = open(filename, O_RDWR | O_CREAT | O_EXCL, 0600);
filename)));
close(fd);
+ if (len == 0)
+ {
+ ereport(FATAL,
+ (errcode(ERRCODE_LOCK_FILE_EXISTS),
+ errmsg("lock file \"%s\" is empty", filename),
+ errhint("Either another server is starting, or the lock file is the remnant of a previous server startup crash.")));
+ }
+
buffer[len] = '\0';
encoded_pid = atoi(buffer);
/*
* Check to see if the other process still exists
*
- * If the PID in the lockfile is our own PID or our parent's PID, then
- * the file must be stale (probably left over from a previous system
- * boot cycle). We need this test because of the likelihood that a
- * reboot will assign exactly the same PID as we had in the previous
- * reboot. Also, if there is just one more process launch in this
- * reboot than in the previous one, the lockfile might mention our
- * parent's PID. We can reject that since we'd never be launched
- * directly by a competing postmaster. We can't detect grandparent
- * processes unfortunately, but if the init script is written
- * carefully then all but the immediate parent shell will be
- * root-owned processes and so the kill test will fail with EPERM.
+ * Per discussion above, my_pid, my_p_pid, and my_gp_pid can be
+ * ignored as false matches.
+ *
+ * Normally kill() will fail with ESRCH if the given PID doesn't
+ * exist.
*
* We can treat the EPERM-error case as okay because that error
* implies that the existing process has a different userid than we
* do, which means it cannot be a competing postmaster. A postmaster
* cannot successfully attach to a data directory owned by a userid
- * other than its own. (This is now checked directly in
+ * other than its own. (This is now checked directly in
* checkDataDir(), but has been true for a long time because of the
* restriction that the data directory isn't group- or
* world-accessible.) Also, since we create the lockfiles mode 600,
* Unix socket file belonging to an instance of Postgres being run by
* someone else, at least on machines where /tmp hasn't got a
* stickybit.)
- *
- * Windows hasn't got getppid(), but doesn't need it since it's not
- * using real kill() either...
- *
- * Normally kill() will fail with ESRCH if the given PID doesn't
- * exist.
*/
- if (other_pid != my_pid
-#ifndef WIN32
- && other_pid != getppid()
-#endif
- )
+ if (other_pid != my_pid && other_pid != my_p_pid &&
+ other_pid != my_gp_pid)
{
if (kill(other_pid, 0) == 0 ||
(errno != ESRCH && errno != EPERM))
}
/*
- * No, the creating process did not exist. However, it could be that
+ * No, the creating process did not exist. However, it could be that
* the postmaster crashed (or more likely was kill -9'd by a clueless
- * admin) but has left orphan backends behind. Check for this by
+ * admin) but has left orphan backends behind. Check for this by
* looking to see if there is an associated shmem segment that is
* still in use.
+ *
+ * Note: because postmaster.pid is written in multiple steps, we might
+ * not find the shmem ID values in it; we can't treat that as an
+ * error.
*/
if (isDDLock)
{
- char *ptr;
+ char *ptr = buffer;
unsigned long id1,
id2;
+ int lineno;
- ptr = strchr(buffer, '\n');
- if (ptr != NULL &&
- (ptr = strchr(ptr + 1, '\n')) != NULL)
+ for (lineno = 1; lineno < LOCK_FILE_LINE_SHMEM_KEY; lineno++)
{
+ if ((ptr = strchr(ptr, '\n')) == NULL)
+ break;
ptr++;
- if (sscanf(ptr, "%lu %lu", &id1, &id2) == 2)
- {
- if (PGSharedMemoryIsInUse(id1, id2))
- ereport(FATAL,
- (errcode(ERRCODE_LOCK_FILE_EXISTS),
- errmsg("pre-existing shared memory block "
- "(key %lu, ID %lu) is still in use",
- id1, id2),
- errhint("If you're sure there are no old "
- "server processes still running, remove "
- "the shared memory block with "
- "the command \"ipcclean\", \"ipcrm\", "
- "or just delete the file \"%s\".",
- filename)));
- }
+ }
+
+ if (ptr != NULL &&
+ sscanf(ptr, "%lu %lu", &id1, &id2) == 2)
+ {
+ if (PGSharedMemoryIsInUse(id1, id2))
+ ereport(FATAL,
+ (errcode(ERRCODE_LOCK_FILE_EXISTS),
+ errmsg("pre-existing shared memory block "
+ "(key %lu, ID %lu) is still in use",
+ id1, id2),
+ errhint("If you're sure there are no old "
+ "server processes still running, remove "
+ "the shared memory block "
+ "or just delete the file \"%s\".",
+ filename)));
}
}
/*
* Looks like nobody's home. Unlink the file and try again to create
- * it. Need a loop because of possible race condition against other
+ * it. Need a loop because of possible race condition against other
* would-be creators.
*/
if (unlink(filename) < 0)
}
/*
- * Successfully created the file, now fill it.
+ * Successfully created the file, now fill it. See comment in miscadmin.h
+ * about the contents. Note that we write the same first five lines into
+ * both datadir and socket lockfiles; although more stuff may get added to
+ * the datadir lockfile later.
*/
- snprintf(buffer, sizeof(buffer), "%d\n%s\n",
+ snprintf(buffer, sizeof(buffer), "%d\n%s\n%ld\n%d\n%s\n",
amPostmaster ? (int) my_pid : -((int) my_pid),
- DataDir);
+ DataDir,
+ (long) MyStartTime,
+ PostPortNumber,
+ socketDir);
+
+ /*
+ * In a standalone backend, the next line (LOCK_FILE_LINE_LISTEN_ADDR)
+ * will never receive data, so fill it in as empty now.
+ */
+ if (isDDLock && !amPostmaster)
+ strlcat(buffer, "\n", sizeof(buffer));
+
errno = 0;
if (write(fd, buffer, strlen(buffer)) != strlen(buffer))
{
(errcode_for_file_access(),
errmsg("could not write lock file \"%s\": %m", filename)));
}
- if (close(fd))
+ if (pg_fsync(fd) != 0)
{
int save_errno = errno;
+ close(fd);
unlink(filename);
errno = save_errno;
ereport(FATAL,
(errcode_for_file_access(),
errmsg("could not write lock file \"%s\": %m", filename)));
}
+ if (close(fd) != 0)
+ {
+ int save_errno = errno;
+
+ unlink(filename);
+ errno = save_errno;
+ ereport(FATAL,
+ (errcode_for_file_access(),
+ errmsg("could not write lock file \"%s\": %m", filename)));
+ }
+
+ /*
+ * Arrange to unlink the lock file(s) at proc_exit. If this is the first
+ * one, set up the on_proc_exit function to do it; then add this lock file
+ * to the list of files to unlink.
+ */
+ if (lock_files == NIL)
+ on_proc_exit(UnlinkLockFiles, 0);
/*
- * Arrange for automatic removal of lockfile at proc_exit.
+ * Use lcons so that the lock files are unlinked in reverse order of
+ * creation; this is critical!
*/
- on_proc_exit(UnlinkLockFile, PointerGetDatum(strdup(filename)));
+ lock_files = lcons(pstrdup(filename), lock_files);
}
/*
* When this is called, we must have already switched the working
* directory to DataDir, so we can just use a relative path. This
* helps ensure that we are locking the directory we should be.
+ *
+ * Note that the socket directory path line is initially written as empty.
+ * postmaster.c will rewrite it upon creating the first Unix socket.
*/
void
CreateDataDirLockFile(bool amPostmaster)
{
- CreateLockFile(DIRECTORY_LOCK_FILE, amPostmaster, true, DataDir);
+ CreateLockFile(DIRECTORY_LOCK_FILE, amPostmaster, "", true, DataDir);
}
/*
* Create a lockfile for the specified Unix socket file.
*/
void
-CreateSocketLockFile(const char *socketfile, bool amPostmaster)
+CreateSocketLockFile(const char *socketfile, bool amPostmaster,
+ const char *socketDir)
{
char lockfile[MAXPGPATH];
snprintf(lockfile, sizeof(lockfile), "%s.lock", socketfile);
- CreateLockFile(lockfile, amPostmaster, false, socketfile);
- /* Save name of lockfile for TouchSocketLockFile */
- strcpy(socketLockFile, lockfile);
+ CreateLockFile(lockfile, amPostmaster, socketDir, false, socketfile);
}
/*
- * TouchSocketLockFile -- mark socket lock file as recently accessed
+ * TouchSocketLockFiles -- mark socket lock files as recently accessed
*
- * This routine should be called every so often to ensure that the lock file
- * has a recent mod or access date. That saves it
+ * This routine should be called every so often to ensure that the socket
+ * lock files have a recent mod or access date. That saves them
* from being removed by overenthusiastic /tmp-directory-cleaner daemons.
* (Another reason we should never have put the socket file in /tmp...)
*/
void
-TouchSocketLockFile(void)
+TouchSocketLockFiles(void)
{
- /* Do nothing if we did not create a socket... */
- if (socketLockFile[0] != '\0')
+ ListCell *l;
+
+ foreach(l, lock_files)
{
+ char *socketLockFile = (char *) lfirst(l);
+
+ /* No need to touch the data directory lock file, we trust */
+ if (strcmp(socketLockFile, DIRECTORY_LOCK_FILE) == 0)
+ continue;
+
/*
* utime() is POSIX standard, utimes() is a common alternative; if we
* have neither, fall back to actually reading the file (which only
}
}
+
/*
- * Append information about a shared memory segment to the data directory
- * lock file.
+ * Add (or replace) a line in the data directory lock file.
+ * The given string should not include a trailing newline.
*
- * This may be called multiple times in the life of a postmaster, if we
- * delete and recreate shmem due to backend crash. Therefore, be prepared
- * to overwrite existing information. (As of 7.1, a postmaster only creates
- * one shm seg at a time; but for the purposes here, if we did have more than
- * one then any one of them would do anyway.)
+ * Note: because we don't truncate the file, if we were to rewrite a line
+ * with less data than it had before, there would be garbage after the last
+ * line. We don't ever actually do that, so not worth adding another kernel
+ * call to cover the possibility.
*/
void
-RecordSharedMemoryInLockFile(unsigned long id1, unsigned long id2)
+AddToDataDirLockFile(int target_line, const char *str)
{
int fd;
int len;
- char *ptr;
- char buffer[BLCKSZ];
+ int lineno;
+ char *srcptr;
+ char *destptr;
+ char srcbuffer[BLCKSZ];
+ char destbuffer[BLCKSZ];
fd = open(DIRECTORY_LOCK_FILE, O_RDWR | PG_BINARY, 0);
if (fd < 0)
DIRECTORY_LOCK_FILE)));
return;
}
- len = read(fd, buffer, sizeof(buffer) - 100);
+ len = read(fd, srcbuffer, sizeof(srcbuffer) - 1);
if (len < 0)
{
ereport(LOG,
close(fd);
return;
}
- buffer[len] = '\0';
+ srcbuffer[len] = '\0';
/*
- * Skip over first two lines (PID and path).
+ * Advance over lines we are not supposed to rewrite, then copy them to
+ * destbuffer.
*/
- ptr = strchr(buffer, '\n');
- if (ptr == NULL ||
- (ptr = strchr(ptr + 1, '\n')) == NULL)
+ srcptr = srcbuffer;
+ for (lineno = 1; lineno < target_line; lineno++)
{
- elog(LOG, "bogus data in \"%s\"", DIRECTORY_LOCK_FILE);
- close(fd);
- return;
+ if ((srcptr = strchr(srcptr, '\n')) == NULL)
+ {
+ elog(LOG, "incomplete data in \"%s\": found only %d newlines while trying to add line %d",
+ DIRECTORY_LOCK_FILE, lineno - 1, target_line);
+ close(fd);
+ return;
+ }
+ srcptr++;
}
- ptr++;
+ memcpy(destbuffer, srcbuffer, srcptr - srcbuffer);
+ destptr = destbuffer + (srcptr - srcbuffer);
/*
- * Append key information. Format to try to keep it the same length
- * always (trailing junk won't hurt, but might confuse humans).
+ * Write or rewrite the target line.
*/
- sprintf(ptr, "%9lu %9lu\n", id1, id2);
+ snprintf(destptr, destbuffer + sizeof(destbuffer) - destptr, "%s\n", str);
+ destptr += strlen(destptr);
+
+ /*
+ * If there are more lines in the old file, append them to destbuffer.
+ */
+ if ((srcptr = strchr(srcptr, '\n')) != NULL)
+ {
+ srcptr++;
+ snprintf(destptr, destbuffer + sizeof(destbuffer) - destptr, "%s",
+ srcptr);
+ }
/*
* And rewrite the data. Since we write in a single kernel call, this
* update should appear atomic to onlookers.
*/
- len = strlen(buffer);
+ len = strlen(destbuffer);
errno = 0;
if (lseek(fd, (off_t) 0, SEEK_SET) != 0 ||
- (int) write(fd, buffer, len) != len)
+ (int) write(fd, destbuffer, len) != len)
{
/* if write didn't set errno, assume problem is no disk space */
if (errno == 0)
close(fd);
return;
}
- if (close(fd))
+ if (pg_fsync(fd) != 0)
+ {
+ ereport(LOG,
+ (errcode_for_file_access(),
+ errmsg("could not write to file \"%s\": %m",
+ DIRECTORY_LOCK_FILE)));
+ }
+ if (close(fd) != 0)
{
ereport(LOG,
(errcode_for_file_access(),
}
+/*
+ * Recheck that the data directory lock file still exists with expected
+ * content. Return TRUE if the lock file appears OK, FALSE if it isn't.
+ *
+ * We call this periodically in the postmaster. The idea is that if the
+ * lock file has been removed or replaced by another postmaster, we should
+ * do a panic database shutdown. Therefore, we should return TRUE if there
+ * is any doubt: we do not want to cause a panic shutdown unnecessarily.
+ * Transient failures like EINTR or ENFILE should not cause us to fail.
+ * (If there really is something wrong, we'll detect it on a future recheck.)
+ */
+bool
+RecheckDataDirLockFile(void)
+{
+ int fd;
+ int len;
+ long file_pid;
+ char buffer[BLCKSZ];
+
+ fd = open(DIRECTORY_LOCK_FILE, O_RDWR | PG_BINARY, 0);
+ if (fd < 0)
+ {
+ /*
+ * There are many foreseeable false-positive error conditions. For
+ * safety, fail only on enumerated clearly-something-is-wrong
+ * conditions.
+ */
+ switch (errno)
+ {
+ case ENOENT:
+ case ENOTDIR:
+ /* disaster */
+ ereport(LOG,
+ (errcode_for_file_access(),
+ errmsg("could not open file \"%s\": %m",
+ DIRECTORY_LOCK_FILE)));
+ return false;
+ default:
+ /* non-fatal, at least for now */
+ ereport(LOG,
+ (errcode_for_file_access(),
+ errmsg("could not open file \"%s\": %m; continuing anyway",
+ DIRECTORY_LOCK_FILE)));
+ return true;
+ }
+ }
+ len = read(fd, buffer, sizeof(buffer) - 1);
+ if (len < 0)
+ {
+ ereport(LOG,
+ (errcode_for_file_access(),
+ errmsg("could not read from file \"%s\": %m",
+ DIRECTORY_LOCK_FILE)));
+ close(fd);
+ return true; /* treat read failure as nonfatal */
+ }
+ buffer[len] = '\0';
+ close(fd);
+ file_pid = atol(buffer);
+ if (file_pid == getpid())
+ return true; /* all is well */
+
+ /* Trouble: someone's overwritten the lock file */
+ ereport(LOG,
+ (errmsg("lock file \"%s\" contains wrong PID: %ld instead of %ld",
+ DIRECTORY_LOCK_FILE, file_pid, (long) getpid())));
+ return false;
+}
+
+
/*-------------------------------------------------------------------------
* Version checking support
*-------------------------------------------------------------------------
* GUC variables: lists of library names to be preloaded at postmaster
* start and at backend start
*/
+char *session_preload_libraries_string = NULL;
char *shared_preload_libraries_string = NULL;
char *local_preload_libraries_string = NULL;
+/* Flag telling that we are loading shared_preload_libraries */
+bool process_shared_preload_libraries_in_progress = false;
+
/*
* load the shared libraries listed in 'libraries'
*
{
char *expanded;
- expanded = palloc(strlen("$libdir/plugins/") + strlen(filename) + 1);
- strcpy(expanded, "$libdir/plugins/");
- strcat(expanded, filename);
+ expanded = psprintf("$libdir/plugins/%s", filename);
pfree(filename);
filename = expanded;
}
load_file(filename, restricted);
- ereport(LOG,
+ ereport(DEBUG1,
(errmsg("loaded library \"%s\"", filename)));
pfree(filename);
}
void
process_shared_preload_libraries(void)
{
+ process_shared_preload_libraries_in_progress = true;
load_libraries(shared_preload_libraries_string,
"shared_preload_libraries",
false);
+ process_shared_preload_libraries_in_progress = false;
}
/*
* process any libraries that should be preloaded at backend start
*/
void
-process_local_preload_libraries(void)
+process_session_preload_libraries(void)
{
+ load_libraries(session_preload_libraries_string,
+ "session_preload_libraries",
+ false);
load_libraries(local_preload_libraries_string,
"local_preload_libraries",
true);
}
+
+void
+pg_bindtextdomain(const char *domain)
+{
+#ifdef ENABLE_NLS
+ if (my_exec_path[0] != '\0')
+ {
+ char locale_path[MAXPGPATH];
+
+ get_locale_path(my_exec_path, locale_path);
+ bindtextdomain(domain, locale_path);
+ pg_bind_textdomain_codeset(domain);
+ }
+#endif
+}