* miscinit.c
* miscellaneous initialization support stuff
*
- * Portions Copyright (c) 1996-2003, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1996-2012, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/utils/init/miscinit.c,v 1.114 2003/09/24 18:54:01 tgl Exp $
+ * src/backend/utils/init/miscinit.c
*
*-------------------------------------------------------------------------
*/
#include <unistd.h>
#include <grp.h>
#include <pwd.h>
-#include <errno.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#ifdef HAVE_UTIME_H
#include <utime.h>
#endif
-#include "catalog/catname.h"
-#include "catalog/pg_shadow.h"
-#include "libpq/libpq-be.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/pg_shmem.h"
+#include "storage/proc.h"
+#include "storage/procarray.h"
#include "utils/builtins.h"
#include "utils/guc.h"
-#include "utils/lsyscache.h"
+#include "utils/memutils.h"
#include "utils/syscache.h"
+#define DIRECTORY_LOCK_FILE "postmaster.pid"
+
ProcessingMode Mode = InitProcessing;
-/* Note: we rely on these to initialize as zeroes */
-static char directoryLockFile[MAXPGPATH];
+/* Note: we rely on this to initialize as zeroes */
static char socketLockFile[MAXPGPATH];
*
* 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.
* ----------------------------------------------------------------
*/
-static bool isIgnoringSystemIndexes = false;
+bool IgnoreSystemIndexes = false;
-/*
- * IsIgnoringSystemIndexes
- * True if ignoring system indexes.
- */
-bool
-IsIgnoringSystemIndexes(void)
-{
- return isIgnoringSystemIndexes;
-}
-
-/*
- * IgnoreSystemIndexes
- * Set true or false whether PostgreSQL ignores system indexes.
- */
-void
-IgnoreSystemIndexes(bool mode)
-{
- isIgnoringSystemIndexes = mode;
-}
/* ----------------------------------------------------------------
- * system index reindexing support
- *
- * When we are busy reindexing a system index, this code provides support
- * for preventing catalog lookups from using that index.
+ * database path / name support stuff
* ----------------------------------------------------------------
*/
-static Oid currentlyReindexedHeap = InvalidOid;
-static Oid currentlyReindexedIndex = InvalidOid;
-
-/*
- * ReindexIsProcessingHeap
- * True if heap specified by OID is currently being reindexed.
- */
-bool
-ReindexIsProcessingHeap(Oid heapOid)
+void
+SetDatabasePath(const char *path)
{
- return heapOid == currentlyReindexedHeap;
+ /* This should happen only once per process */
+ Assert(!DatabasePath);
+ DatabasePath = MemoryContextStrdup(TopMemoryContext, path);
}
/*
- * ReindexIsProcessingIndex
- * True if index specified by OID is currently being reindexed.
+ * Set data directory, but make sure it's an absolute path. Use this,
+ * never set DataDir directly.
*/
-bool
-ReindexIsProcessingIndex(Oid indexOid)
+void
+SetDataDir(const char *dir)
{
- return indexOid == currentlyReindexedIndex;
+ char *new;
+
+ AssertArg(dir);
+
+ /* If presented path is relative, convert to absolute */
+ new = make_absolute_path(dir);
+
+ if (DataDir)
+ free(DataDir);
+ DataDir = new;
}
/*
- * SetReindexProcessing
- * Set flag that specified heap/index are being reindexed.
- * Pass InvalidOid to indicate that reindexing is not active.
+ * Change working directory to DataDir. Most of the postmaster and backend
+ * code assumes that we are in DataDir so it can use relative paths to access
+ * stuff in and under the data directory. For convenience during path
+ * setup, however, we don't force the chdir to occur during SetDataDir.
*/
void
-SetReindexProcessing(Oid heapOid, Oid indexOid)
+ChangeToDataDir(void)
{
- /* Args should be both, or neither, InvalidOid */
- Assert((heapOid == InvalidOid) == (indexOid == InvalidOid));
- /* Reindexing is not re-entrant. */
- Assert(indexOid == InvalidOid || currentlyReindexedIndex == InvalidOid);
- currentlyReindexedHeap = heapOid;
- currentlyReindexedIndex = indexOid;
-}
-
-/* ----------------------------------------------------------------
- * database path / name support stuff
- * ----------------------------------------------------------------
- */
+ AssertState(DataDir);
-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);
- }
+ if (chdir(DataDir) < 0)
+ ereport(FATAL,
+ (errcode_for_file_access(),
+ errmsg("could not change directory to \"%s\": %m",
+ DataDir)));
}
/*
- * Set data directory, but make sure it's an absolute path. Use this,
- * never set DataDir directly.
+ * 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.
*/
-void
-SetDataDir(const char *dir)
+char *
+make_absolute_path(const char *path)
{
char *new;
- int newlen;
- AssertArg(dir);
+ /* Returning null for null input is convenient for some callers */
+ if (path == NULL)
+ return NULL;
- /* If presented path is relative, convert to absolute */
- if (!is_absolute_path(dir))
+ if (!is_absolute_path(path))
{
char *buf;
size_t buflen;
}
}
- new = malloc(strlen(buf) + 1 + strlen(dir) + 1);
+ 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, dir);
+ sprintf(new, "%s/%s", buf, path);
free(buf);
}
else
{
- new = strdup(dir);
+ new = strdup(path);
if (!new)
ereport(FATAL,
(errcode(ERRCODE_OUT_OF_MEMORY),
errmsg("out of memory")));
}
- /*
- * Strip any trailing slash. Not strictly necessary, but avoids
- * generating funny-looking paths to individual files.
- */
- newlen = strlen(new);
- if (newlen > 1 && new[newlen - 1] == '/'
-#ifdef WIN32
- || new[newlen - 1] == '\\'
-#endif
- )
- new[newlen - 1] = '\0';
+ /* Make sure punctuation is canonical, too */
+ canonicalize_path(new);
- if (DataDir)
- free(DataDir);
- DataDir = new;
+ return new;
}
/* ----------------------------------------------------------------
- * User ID things
+ * User ID state
+ *
+ * We have to track several different values associated with the concept
+ * of "user ID".
*
- * The authenticated user is determined at connection start and never
- * changes. The session user can be changed only by SET SESSION
- * AUTHORIZATION. The current user may change when "setuid" functions
- * are implemented. Conceptually there is a stack, whose bottom
- * is the session user. You are yourself responsible to save and
- * restore the current user id if you need to change it.
+ * AuthenticatedUserId is determined at connection start and never changes.
+ *
+ * SessionUserId is initially the same as AuthenticatedUserId, but can be
+ * changed by SET SESSION AUTHORIZATION (if AuthenticatedUserIsSuperuser).
+ * This is the ID reported by the SESSION_USER SQL function.
+ *
+ * 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. (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 AclId AuthenticatedUserId = 0;
-static AclId SessionUserId = 0;
-static AclId CurrentUserId = 0;
+static Oid AuthenticatedUserId = InvalidOid;
+static Oid SessionUserId = InvalidOid;
+static Oid OuterUserId = InvalidOid;
+static Oid CurrentUserId = InvalidOid;
+/* We also have to remember the superuser state of some of these levels */
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;
+
/*
- * This function is relevant for all privilege checks.
+ * GetUserId - get the current effective user ID.
+ *
+ * Note: there's no SetUserId() anymore; use SetUserIdAndSecContext().
*/
-AclId
+Oid
GetUserId(void)
{
- AssertState(AclIdIsValid(CurrentUserId));
+ AssertState(OidIsValid(CurrentUserId));
return CurrentUserId;
}
-void
-SetUserId(AclId newid)
+/*
+ * GetOuterUserId/SetOuterUserId - get/set the outer-level user ID.
+ */
+Oid
+GetOuterUserId(void)
+{
+ AssertState(OidIsValid(OuterUserId));
+ return OuterUserId;
+}
+
+
+static void
+SetOuterUserId(Oid userid)
{
- AssertArg(AclIdIsValid(newid));
- CurrentUserId = newid;
+ AssertState(SecurityRestrictionContext == 0);
+ AssertArg(OidIsValid(userid));
+ OuterUserId = userid;
+
+ /* We force the effective user ID to match, too */
+ CurrentUserId = userid;
}
/*
- * This value is only relevant for informational purposes.
+ * GetSessionUserId/SetSessionUserId - get/set the session user ID.
*/
-AclId
+Oid
GetSessionUserId(void)
{
- AssertState(AclIdIsValid(SessionUserId));
+ AssertState(OidIsValid(SessionUserId));
return SessionUserId;
}
+static void
+SetSessionUserId(Oid userid, bool is_superuser)
+{
+ AssertState(SecurityRestrictionContext == 0);
+ AssertArg(OidIsValid(userid));
+ SessionUserId = userid;
+ SessionUserIsSuperuser = is_superuser;
+ SetRoleIsActive = false;
+
+ /* We force the effective user IDs to match, too */
+ OuterUserId = userid;
+ CurrentUserId = userid;
+}
+
+
+/*
+ * GetUserIdAndSecContext/SetUserIdAndSecContext - get/set the current user ID
+ * and the SecurityRestrictionContext flags.
+ *
+ * Currently there are two 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.
+ *
+ * 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;
+}
+
+
+/*
+ * 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
-SetSessionUserId(AclId newid)
+GetUserIdAndContext(Oid *userid, bool *sec_def_context)
{
- AssertArg(AclIdIsValid(newid));
- SessionUserId = newid;
- /* Current user defaults to session user. */
- if (!AclIdIsValid(CurrentUserId))
- CurrentUserId = newid;
+ *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 if the authenticated user is a replication role
+ */
+bool
+is_authenticated_user_replication_role(void)
+{
+ bool result = false;
+ HeapTuple utup;
+
+ utup = SearchSysCache1(AUTHOID, ObjectIdGetDatum(AuthenticatedUserId));
+ 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 *username)
+InitializeSessionUserId(const char *rolename)
{
- HeapTuple userTup;
- Datum datum;
- bool isnull;
- AclId usesysid;
+ HeapTuple roleTup;
+ Form_pg_authid rform;
+ Oid roleid;
/*
* Don't do scans if we're bootstrapping, none of the system catalogs
/* call only once */
AssertState(!OidIsValid(AuthenticatedUserId));
- userTup = SearchSysCache(SHADOWNAME,
- PointerGetDatum(username),
- 0, 0, 0);
- if (!HeapTupleIsValid(userTup))
+ roleTup = SearchSysCache1(AUTHNAME, PointerGetDatum(rolename));
+ if (!HeapTupleIsValid(roleTup))
ereport(FATAL,
- (errcode(ERRCODE_UNDEFINED_OBJECT),
- errmsg("user \"%s\" does not exist", username)));
+ (errcode(ERRCODE_INVALID_AUTHORIZATION_SPECIFICATION),
+ errmsg("role \"%s\" does not exist", rolename)));
- usesysid = ((Form_pg_shadow) GETSTRUCT(userTup))->usesysid;
+ rform = (Form_pg_authid) GETSTRUCT(roleTup);
+ roleid = HeapTupleGetOid(roleTup);
- AuthenticatedUserId = usesysid;
- AuthenticatedUserIsSuperuser = ((Form_pg_shadow) GETSTRUCT(userTup))->usesuper;
+ AuthenticatedUserId = roleid;
+ AuthenticatedUserIsSuperuser = rform->rolsuper;
- SetSessionUserId(usesysid); /* sets CurrentUserId too */
+ /* This sets OuterUserId/CurrentUserId too */
+ SetSessionUserId(roleid, AuthenticatedUserIsSuperuser);
- /* Record username and superuser status as GUC settings too */
- SetConfigOption("session_authorization", username,
- PGC_BACKEND, PGC_S_OVERRIDE);
- SetConfigOption("is_superuser",
- AuthenticatedUserIsSuperuser ? "on" : "off",
- PGC_INTERNAL, PGC_S_OVERRIDE);
+ /* Also mark our PGPROC entry with the authenticated user id */
+ /* (We assume this is an atomic store so no lock is needed) */
+ MyProc->roleId = roleid;
/*
- * Set up user-specific configuration variables. This is a good place
- * to do it so we don't have to read pg_shadow twice during session
- * startup.
+ * 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;".
*/
- datum = SysCacheGetAttr(SHADOWNAME, userTup,
- Anum_pg_shadow_useconfig, &isnull);
- if (!isnull)
+ if (IsUnderPostmaster)
{
- ArrayType *a = DatumGetArrayTypeP(datum);
+ /*
+ * Is role allowed to login at all?
+ */
+ if (!rform->rolcanlogin)
+ ereport(FATAL,
+ (errcode(ERRCODE_INVALID_AUTHORIZATION_SPECIFICATION),
+ errmsg("role \"%s\" is not permitted to log in",
+ rolename)));
- ProcessGUCArray(a, PGC_S_USER);
+ /*
+ * 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
+ * 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
+ * just document that the connection limit is approximate.
+ */
+ if (rform->rolconnlimit >= 0 &&
+ !AuthenticatedUserIsSuperuser &&
+ CountUserBackends(roleid) > rform->rolconnlimit)
+ ereport(FATAL,
+ (errcode(ERRCODE_TOO_MANY_CONNECTIONS),
+ errmsg("too many connections for role \"%s\"",
+ rolename)));
}
- ReleaseSysCache(userTup);
+ /* Record username and superuser status as GUC settings too */
+ SetConfigOption("session_authorization", rolename,
+ PGC_BACKEND, PGC_S_OVERRIDE);
+ SetConfigOption("is_superuser",
+ AuthenticatedUserIsSuperuser ? "on" : "off",
+ PGC_INTERNAL, PGC_S_OVERRIDE);
+
+ ReleaseSysCache(roleTup);
}
+/*
+ * Initialize user identity during special backend startup
+ */
void
InitializeSessionUserIdStandalone(void)
{
- /* This function should only be called in a single-user backend. */
- AssertState(!IsUnderPostmaster);
+ /*
+ * This function should only be called in single-user mode and in
+ * autovacuum workers.
+ */
+ AssertState(!IsUnderPostmaster || IsAutoVacuumWorkerProcess());
/* call only once */
AssertState(!OidIsValid(AuthenticatedUserId));
- AuthenticatedUserId = BOOTSTRAP_USESYSID;
+ AuthenticatedUserId = BOOTSTRAP_SUPERUSERID;
AuthenticatedUserIsSuperuser = true;
- SetSessionUserId(BOOTSTRAP_USESYSID);
+ SetSessionUserId(BOOTSTRAP_SUPERUSERID, true);
}
* that in case of multiple SETs in a single session, the original userid's
* superuserness is what matters. But we set the GUC variable is_superuser
* to indicate whether the *current* session userid is a superuser.
+ *
+ * Note: this is not an especially clean place to do the permission check.
+ * It's OK because the check does not require catalog access and can't
+ * fail during an end-of-transaction GUC reversion, but we may someday
+ * have to push it up into assign_session_authorization.
*/
void
-SetSessionAuthorization(AclId userid, bool is_superuser)
+SetSessionAuthorization(Oid userid, bool is_superuser)
{
/* Must have authenticated already, else can't make permission check */
- AssertState(AclIdIsValid(AuthenticatedUserId));
+ AssertState(OidIsValid(AuthenticatedUserId));
if (userid != AuthenticatedUserId &&
!AuthenticatedUserIsSuperuser)
ereport(ERROR,
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
- errmsg("permission denied to set session authorization")));
+ errmsg("permission denied to set session authorization")));
+
+ SetSessionUserId(userid, is_superuser);
+
+ SetConfigOption("is_superuser",
+ is_superuser ? "on" : "off",
+ PGC_INTERNAL, PGC_S_OVERRIDE);
+}
+
+/*
+ * Report current role id
+ * This follows the semantics of SET ROLE, ie return the outer-level ID
+ * not the current effective ID, and return InvalidOid when the setting
+ * is logically SET ROLE NONE.
+ */
+Oid
+GetCurrentRoleId(void)
+{
+ if (SetRoleIsActive)
+ return OuterUserId;
+ else
+ return InvalidOid;
+}
+
+/*
+ * 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
+ * is ignored.
+ *
+ * When roleid is not InvalidOid, the caller must have checked whether
+ * the session user has permission to become that role. (We cannot check
+ * here because this routine must be able to execute in a failed transaction
+ * to restore a prior value of the ROLE GUC variable.)
+ */
+void
+SetCurrentRoleId(Oid roleid, bool is_superuser)
+{
+ /*
+ * Get correct info if it's SET ROLE NONE
+ *
+ * If SessionUserId hasn't been set yet, just do nothing --- the eventual
+ * SetSessionUserId call will fix everything. This is needed since we
+ * will get called during GUC initialization.
+ */
+ if (!OidIsValid(roleid))
+ {
+ if (!OidIsValid(SessionUserId))
+ return;
+
+ roleid = SessionUserId;
+ is_superuser = SessionUserIsSuperuser;
+
+ SetRoleIsActive = false;
+ }
+ else
+ SetRoleIsActive = true;
- SetSessionUserId(userid);
- SetUserId(userid);
+ SetOuterUserId(roleid);
SetConfigOption("is_superuser",
is_superuser ? "on" : "off",
/*
- * Get user name from user id
+ * Get user name from user oid
*/
char *
-GetUserNameFromId(AclId userid)
+GetUserNameFromId(Oid roleid)
{
HeapTuple tuple;
char *result;
- tuple = SearchSysCache(SHADOWSYSID,
- ObjectIdGetDatum(userid),
- 0, 0, 0);
+ tuple = SearchSysCache1(AUTHOID, ObjectIdGetDatum(roleid));
if (!HeapTupleIsValid(tuple))
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_OBJECT),
- errmsg("invalid user id: %d", userid)));
+ errmsg("invalid role OID: %u", roleid)));
- result = pstrdup(NameStr(((Form_pg_shadow) GETSTRUCT(tuple))->usename));
+ 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.
+ * 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.
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;
+
+ /*
+ * 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
/*
- * 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.
+ * 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.
*/
for (ntries = 0;; ntries++)
{
/*
* Try to create the lock file --- O_EXCL makes this atomic.
+ *
+ * Think not to make the file protection weaker than 0600. See
+ * comments below.
*/
fd = open(filename, O_RDWR | O_CREAT | O_EXCL, 0600);
if (fd >= 0)
errmsg("could not open lock file \"%s\": %m",
filename)));
}
- if ((len = read(fd, buffer, sizeof(buffer) - 1)) <= 0)
+ if ((len = read(fd, buffer, sizeof(buffer) - 1)) < 0)
ereport(FATAL,
(errcode_for_file_access(),
errmsg("could not read lock file \"%s\": %m",
other_pid = (pid_t) (encoded_pid < 0 ? -encoded_pid : encoded_pid);
if (other_pid <= 0)
- elog(FATAL, "bogus data in lock file \"%s\"", filename);
+ elog(FATAL, "bogus data in lock file \"%s\": \"%s\"",
+ filename, buffer);
/*
* Check to see if the other process still exists
*
+ * 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. BeOS returns EINVAL for some silly reason, however.
+ * 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
+ * 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,
+ * we'd have failed above if the lockfile belonged to another userid
+ * --- which means that whatever process kill() is reporting about
+ * isn't the one that made the lockfile. (NOTE: this last
+ * consideration is the only one that keeps us from blowing away a
+ * 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.)
*/
- if (other_pid != my_pid)
+ if (other_pid != my_pid && other_pid != my_p_pid &&
+ other_pid != my_gp_pid)
{
if (kill(other_pid, 0) == 0 ||
- (errno != ESRCH
-#ifdef __BEOS__
- && errno != EINVAL
-#endif
- ))
+ (errno != ESRCH && errno != EPERM))
{
/* lockfile belongs to a live process */
ereport(FATAL,
errmsg("lock file \"%s\" already exists",
filename),
isDDLock ?
- errhint("Is another %s (pid %d) running in \"%s\"?",
- (encoded_pid < 0 ? "postgres" : "postmaster"),
- (int) other_pid, refName) :
- errhint("Is another %s (pid %d) using \"%s\"?",
- (encoded_pid < 0 ? "postgres" : "postmaster"),
- (int) other_pid, refName)));
+ (encoded_pid < 0 ?
+ errhint("Is another postgres (PID %d) running in data directory \"%s\"?",
+ (int) other_pid, refName) :
+ errhint("Is another postmaster (PID %d) running in data directory \"%s\"?",
+ (int) other_pid, refName)) :
+ (encoded_pid < 0 ?
+ errhint("Is another postgres (PID %d) using socket file \"%s\"?",
+ (int) other_pid, refName) :
+ errhint("Is another postmaster (PID %d) using socket file \"%s\"?",
+ (int) other_pid, refName))));
}
}
/*
- * 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 looking to see if there is an associated shmem segment
- * that is still in use.
+ * 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
+ * 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 "
- "backends still running, remove "
- "the shared memory block with "
- "ipcrm(1), or just delete \"%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 would-be creators.
+ * Looks like nobody's home. Unlink the file and try again to create
+ * it. Need a loop because of possible race condition against other
+ * would-be creators.
*/
if (unlink(filename) < 0)
ereport(FATAL,
errmsg("could not remove old lock file \"%s\": %m",
filename),
errhint("The file seems accidentally left over, but "
- "I couldn't remove it. Please remove the file "
+ "it could not be removed. Please remove the file "
"by hand and try again.")));
}
/*
- * 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 info 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,
+#ifdef HAVE_UNIX_SOCKETS
+ (*UnixSocketDir != '\0') ? UnixSocketDir : DEFAULT_PGSOCKET_DIR
+#else
+ ""
+#endif
+ );
+
errno = 0;
if (write(fd, buffer, strlen(buffer)) != strlen(buffer))
{
errno = save_errno ? save_errno : ENOSPC;
ereport(FATAL,
(errcode_for_file_access(),
- errmsg("could not write lock file \"%s\": %m", filename)));
+ errmsg("could not write lock file \"%s\": %m", filename)));
+ }
+ 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)));
}
- close(fd);
/*
* Arrange for automatic removal of lockfile at proc_exit.
on_proc_exit(UnlinkLockFile, PointerGetDatum(strdup(filename)));
}
+/*
+ * Create the data directory lockfile.
+ *
+ * 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.
+ */
void
-CreateDataDirLockFile(const char *datadir, bool amPostmaster)
+CreateDataDirLockFile(bool amPostmaster)
{
- char lockfile[MAXPGPATH];
-
- snprintf(lockfile, sizeof(lockfile), "%s/postmaster.pid", datadir);
- CreateLockFile(lockfile, amPostmaster, true, datadir);
- /* Save name of lockfile for RecordSharedMemoryInLockFile */
- strcpy(directoryLockFile, lockfile);
+ CreateLockFile(DIRECTORY_LOCK_FILE, amPostmaster, true, DataDir);
}
+/*
+ * Create a lockfile for the specified Unix socket file.
+ */
void
CreateSocketLockFile(const char *socketfile, bool amPostmaster)
{
if (socketLockFile[0] != '\0')
{
/*
- * utime() is POSIX standard, utimes() is a common alternative; if
- * we have neither, fall back to actually reading the file (which
- * only sets the access time not mod time, but that should be
- * enough in most cases). In all paths, we ignore errors.
+ * utime() is POSIX standard, utimes() is a common alternative; if we
+ * have neither, fall back to actually reading the file (which only
+ * sets the access time not mod time, but that should be enough in
+ * most cases). In all paths, we ignore errors.
*/
#ifdef HAVE_UTIME
utime(socketLockFile, NULL);
}
}
+
/*
- * Append information about a shared memory segment to the data directory
- * lock file (if we have created one).
+ * 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.)
+ * Caution: this erases all following lines. In current usage that is OK
+ * because lines are added in order. We could improve it if needed.
*/
void
-RecordSharedMemoryInLockFile(unsigned long id1, unsigned long id2)
+AddToDataDirLockFile(int target_line, const char *str)
{
int fd;
int len;
+ int lineno;
char *ptr;
char buffer[BLCKSZ];
- /*
- * Do nothing if we did not create a lockfile (probably because we are
- * running standalone).
- */
- if (directoryLockFile[0] == '\0')
- return;
-
- fd = open(directoryLockFile, O_RDWR | PG_BINARY, 0);
+ fd = open(DIRECTORY_LOCK_FILE, O_RDWR | PG_BINARY, 0);
if (fd < 0)
{
ereport(LOG,
(errcode_for_file_access(),
- errmsg("could not rewrite \"%s\": %m",
- directoryLockFile)));
+ errmsg("could not open file \"%s\": %m",
+ DIRECTORY_LOCK_FILE)));
return;
}
- len = read(fd, buffer, sizeof(buffer) - 100);
- if (len <= 0)
+ len = read(fd, buffer, sizeof(buffer) - 1);
+ if (len < 0)
{
ereport(LOG,
(errcode_for_file_access(),
- errmsg("could not read \"%s\": %m",
- directoryLockFile)));
+ errmsg("could not read from file \"%s\": %m",
+ DIRECTORY_LOCK_FILE)));
close(fd);
return;
}
buffer[len] = '\0';
/*
- * Skip over first two lines (PID and path).
+ * Skip over lines we are not supposed to rewrite.
*/
- ptr = strchr(buffer, '\n');
- if (ptr == NULL ||
- (ptr = strchr(ptr + 1, '\n')) == NULL)
+ ptr = buffer;
+ for (lineno = 1; lineno < target_line; lineno++)
{
- elog(LOG, "bogus data in \"%s\"", directoryLockFile);
- close(fd);
- return;
+ if ((ptr = strchr(ptr, '\n')) == NULL)
+ {
+ elog(LOG, "bogus data in \"%s\"", DIRECTORY_LOCK_FILE);
+ close(fd);
+ return;
+ }
+ ptr++;
}
- ptr++;
/*
- * 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(ptr, buffer + sizeof(buffer) - ptr, "%s\n", str);
/*
* And rewrite the data. Since we write in a single kernel call, this
errno = ENOSPC;
ereport(LOG,
(errcode_for_file_access(),
- errmsg("could not write \"%s\": %m",
- directoryLockFile)));
+ errmsg("could not write to file \"%s\": %m",
+ DIRECTORY_LOCK_FILE)));
close(fd);
return;
}
- 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(),
+ errmsg("could not write to file \"%s\": %m",
+ DIRECTORY_LOCK_FILE)));
+ }
}
else
ereport(FATAL,
(errcode_for_file_access(),
- errmsg("could not open \"%s\": %m", full_path)));
+ errmsg("could not open file \"%s\": %m", full_path)));
}
ret = fscanf(file, "%ld.%ld", &file_major, &file_minor);
path),
errdetail("File \"%s\" does not contain valid data.",
full_path),
- errhint("You may need to initdb.")));
+ errhint("You might need to initdb.")));
FreeFile(file);
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("database files are incompatible with server"),
errdetail("The data directory was initialized by PostgreSQL version %ld.%ld, "
- "which is not compatible with this version %s.",
+ "which is not compatible with this version %s.",
file_major, file_minor, version_string)));
}
*-------------------------------------------------------------------------
*/
-#if defined(__mc68000__) && defined(__ELF__)
-typedef int32 ((*func_ptr) ());
+/*
+ * GUC variables: lists of library names to be preloaded at postmaster
+ * start and at backend start
+ */
+char *shared_preload_libraries_string = NULL;
+char *local_preload_libraries_string = NULL;
-#else
-typedef char *((*func_ptr) ());
-#endif
+/* Flag telling that we are loading shared_preload_libraries */
+bool process_shared_preload_libraries_in_progress = false;
/*
- * process any libraries that should be preloaded and
- * optionally pre-initialized
+ * load the shared libraries listed in 'libraries'
+ *
+ * 'gucname': name of GUC variable, for error reports
+ * 'restricted': if true, force libraries to be in $libdir/plugins/
*/
-void
-process_preload_libraries(char *preload_libraries_string)
+static void
+load_libraries(const char *libraries, const char *gucname, bool restricted)
{
char *rawstring;
List *elemlist;
- List *l;
+ int elevel;
+ ListCell *l;
- if (preload_libraries_string == NULL)
- return;
+ if (libraries == NULL || libraries[0] == '\0')
+ return; /* nothing to do */
/* Need a modifiable copy of string */
- rawstring = pstrdup(preload_libraries_string);
+ rawstring = pstrdup(libraries);
/* Parse string into list of identifiers */
if (!SplitIdentifierString(rawstring, ',', &elemlist))
{
/* syntax error in list */
pfree(rawstring);
- freeList(elemlist);
+ list_free(elemlist);
ereport(LOG,
(errcode(ERRCODE_SYNTAX_ERROR),
- errmsg("invalid list syntax for preload_libraries configuration option")));
+ errmsg("invalid list syntax in parameter \"%s\"",
+ gucname)));
return;
}
+ /*
+ * Choose notice level: avoid repeat messages when re-loading a library
+ * that was preloaded into the postmaster. (Only possible in EXEC_BACKEND
+ * configurations)
+ */
+#ifdef EXEC_BACKEND
+ if (IsUnderPostmaster && process_shared_preload_libraries_in_progress)
+ elevel = DEBUG2;
+ else
+#endif
+ elevel = LOG;
+
foreach(l, elemlist)
{
char *tok = (char *) lfirst(l);
- char *sep = strstr(tok, ":");
- char *filename = NULL;
- char *funcname = NULL;
- func_ptr initfunc;
+ char *filename;
- if (sep)
+ filename = pstrdup(tok);
+ canonicalize_path(filename);
+ /* If restricting, insert $libdir/plugins if not mentioned already */
+ if (restricted && first_dir_separator(filename) == NULL)
{
- /*
- * a colon separator implies there is an initialization
- * function that we need to run in addition to loading the
- * library
- */
- size_t filename_len = sep - tok;
- size_t funcname_len = strlen(tok) - filename_len - 1;
-
- filename = (char *) palloc(filename_len + 1);
- memcpy(filename, tok, filename_len);
- filename[filename_len] = '\0';
-
- funcname = (char *) palloc(funcname_len + 1);
- strcpy(funcname, sep + 1);
- }
- else
- {
- /*
- * no separator -- just load the library
- */
- filename = pstrdup(tok);
- funcname = NULL;
- }
-
- initfunc = (func_ptr) load_external_function(filename, funcname,
- true, NULL);
- if (initfunc)
- (*initfunc) ();
-
- if (funcname)
- ereport(LOG,
- (errmsg("preloaded library \"%s\" with initialization function \"%s\"",
- filename, funcname)));
- else
- ereport(LOG,
- (errmsg("preloaded library \"%s\"",
- filename)));
+ char *expanded;
+ expanded = palloc(strlen("$libdir/plugins/") + strlen(filename) + 1);
+ strcpy(expanded, "$libdir/plugins/");
+ strcat(expanded, filename);
+ pfree(filename);
+ filename = expanded;
+ }
+ load_file(filename, restricted);
+ ereport(elevel,
+ (errmsg("loaded library \"%s\"", filename)));
pfree(filename);
- if (funcname)
- pfree(funcname);
}
pfree(rawstring);
- freeList(elemlist);
+ list_free(elemlist);
+}
+
+/*
+ * process any libraries that should be preloaded at postmaster start
+ */
+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)
+{
+ 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
}
projects / postgresql / blobdiff