| /*------------------------------------------------------------------------- |
| * |
| * miscinit.c |
| * miscellaneous initialization support stuff |
| * |
| * Portions Copyright (c) 1996-2009, PostgreSQL Global Development Group |
| * Portions Copyright (c) 1994, Regents of the University of California |
| * |
| * |
| * IDENTIFICATION |
| * $PostgreSQL: pgsql/src/backend/utils/init/miscinit.c,v 1.159 2006/10/04 00:30:02 momjian Exp $ |
| * |
| *------------------------------------------------------------------------- |
| */ |
| #include "postgres.h" |
| |
| #include <sys/param.h> |
| #include <signal.h> |
| #include <sys/file.h> |
| #include <sys/stat.h> |
| #include <sys/time.h> |
| #include <fcntl.h> |
| #include <unistd.h> |
| #include <grp.h> |
| #include <pwd.h> |
| #include <netinet/in.h> |
| #include <arpa/inet.h> |
| #ifdef HAVE_UTIME_H |
| #include <utime.h> |
| #endif |
| |
| #include "catalog/catquery.h" |
| #include "catalog/pg_authid.h" |
| #include "cdb/cdbvars.h" |
| #include "mb/pg_wchar.h" |
| #include "miscadmin.h" |
| #include "postmaster/autovacuum.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/resscheduler.h" |
| #include "utils/syscache.h" |
| |
| |
| #define DIRECTORY_LOCK_FILE "postmaster.pid" |
| |
| ProcessingMode Mode = InitProcessing; |
| |
| /* Note: we rely on this to initialize as zeroes */ |
| static char socketLockFile[MAXPGPATH]; |
| |
| |
| /* ---------------------------------------------------------------- |
| * 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 |
| * 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; |
| TempPath = NULL; |
| } |
| /* use strdup since this is done before memory contexts are set up */ |
| if (path) |
| { |
| DatabasePath = strdup(path); |
| if(!DatabasePath) |
| ereport(ERROR, (errcode(ERRCODE_OUT_OF_MEMORY), |
| errmsg("Set database path failed: out of memory"))); |
| TempPath = DatabasePath; |
| AssertState(DatabasePath); |
| } |
| } |
| |
| /* |
| * Set data directory, but make sure it's an absolute path. Use this, |
| * never set DataDir directly. |
| */ |
| void |
| SetDataDir(const char *dir) |
| { |
| char *new; |
| |
| AssertArg(dir); |
| |
| /* If presented path is relative, convert to absolute */ |
| new = make_absolute_path(dir); |
| |
| if (DataDir) |
| free(DataDir); |
| DataDir = new; |
| } |
| |
| /* |
| * 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 |
| ChangeToDataDir(void) |
| { |
| AssertState(DataDir); |
| |
| if (chdir(DataDir) < 0) |
| ereport(FATAL, |
| (errcode_for_file_access(), |
| errmsg("could not change directory to \"%s\": %m", |
| 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 |
| * |
| * We have to track several different values associated with the concept |
| * of "user ID". |
| * |
| * 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. |
| * |
| * SecurityDefinerContext is TRUE if we are within a SECURITY DEFINER function |
| * or another context that temporarily changes CurrentUserId. |
| * ---------------------------------------------------------------- |
| */ |
| 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 bool SecurityDefinerContext = false; |
| |
| /* We also remember if a SET ROLE is currently active */ |
| static bool SetRoleIsActive = false; |
| |
| |
| /* |
| * GetUserId - get the current effective user ID. |
| * |
| * Note: there's no SetUserId() anymore; use SetUserIdAndContext(). |
| */ |
| Oid |
| GetUserId(void) |
| { |
| AssertState(OidIsValid(CurrentUserId)); |
| return CurrentUserId; |
| } |
| |
| |
| /* |
| * GetOuterUserId/SetOuterUserId - get/set the outer-level user ID. |
| */ |
| Oid |
| GetOuterUserId(void) |
| { |
| AssertState(OidIsValid(OuterUserId)); |
| return OuterUserId; |
| } |
| |
| |
| static void |
| SetOuterUserId(Oid userid) |
| { |
| AssertState(!SecurityDefinerContext); |
| AssertArg(OidIsValid(userid)); |
| OuterUserId = userid; |
| |
| /* We force the effective user ID to match, too */ |
| CurrentUserId = userid; |
| } |
| |
| |
| /* |
| * GetSessionUserId/SetSessionUserId - get/set the session user ID. |
| */ |
| Oid |
| GetSessionUserId(void) |
| { |
| AssertState(OidIsValid(SessionUserId)); |
| return SessionUserId; |
| } |
| |
| /* extern so DispatchAgent can use this (postgres.c) */ |
| extern void |
| SetSessionUserId(Oid userid, bool is_superuser) |
| { |
| AssertState(!SecurityDefinerContext); |
| AssertArg(OidIsValid(userid)); |
| SessionUserId = userid; |
| SessionUserIsSuperuser = is_superuser; |
| SetRoleIsActive = false; |
| |
| /* We force the effective user IDs to match, too */ |
| OuterUserId = userid; |
| CurrentUserId = userid; |
| } |
| |
| bool |
| IsAuthenticatedUserSuperUser() |
| { |
| AssertState(OidIsValid(AuthenticatedUserId)); |
| return AuthenticatedUserIsSuperuser; |
| } |
| |
| /* |
| * GetAuthenticatedUserId |
| */ |
| Oid |
| GetAuthenticatedUserId(void) |
| { |
| AssertState(OidIsValid(AuthenticatedUserId)); |
| return AuthenticatedUserId; |
| } |
| |
| /* |
| * GetUserIdAndContext/SetUserIdAndContext - get/set the current user ID |
| * and the SecurityDefinerContext flag. |
| * |
| * Unlike GetUserId, GetUserIdAndContext does *not* Assert that the current |
| * value of CurrentUserId is valid; nor does SetUserIdAndContext 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 |
| GetUserIdAndContext(Oid *userid, bool *sec_def_context) |
| { |
| *userid = CurrentUserId; |
| *sec_def_context = SecurityDefinerContext; |
| } |
| |
| void |
| SetUserIdAndContext(Oid userid, bool sec_def_context) |
| { |
| CurrentUserId = userid; |
| SecurityDefinerContext = sec_def_context; |
| } |
| |
| |
| /* |
| * InSecurityDefinerContext - are we inside a SECURITY DEFINER context? |
| */ |
| bool |
| InSecurityDefinerContext(void) |
| { |
| return SecurityDefinerContext; |
| } |
| |
| |
| /* |
| * Initialize user identity during normal backend startup |
| */ |
| void |
| InitializeSessionUserId(const char *rolename) |
| { |
| HeapTuple roleTup; |
| Form_pg_authid rform; |
| Datum datum; |
| bool isnull; |
| Oid roleid; |
| cqContext *pcqCtx; |
| /* |
| * Don't do scans if we're bootstrapping, none of the system catalogs |
| * exist yet, and they should be owned by postgres anyway. |
| */ |
| AssertState(!IsBootstrapProcessingMode()); |
| |
| /* call only once */ |
| AssertState(!OidIsValid(AuthenticatedUserId)); |
| |
| pcqCtx = caql_beginscan( |
| NULL, |
| cql("SELECT * FROM pg_authid " |
| " WHERE rolname = :1 ", |
| PointerGetDatum((char *) rolename))); |
| |
| roleTup = caql_getnext(pcqCtx); |
| |
| if (!HeapTupleIsValid(roleTup)) |
| ereport(FATAL, |
| (errcode(ERRCODE_INVALID_AUTHORIZATION_SPECIFICATION), |
| errmsg("role \"%s\" does not exist", rolename), |
| errOmitLocation(true), errSendAlert(false))); |
| |
| rform = (Form_pg_authid) GETSTRUCT(roleTup); |
| roleid = HeapTupleGetOid(roleTup); |
| |
| AuthenticatedUserId = roleid; |
| AuthenticatedUserIsSuperuser = rform->rolsuper; |
| |
| /* This sets OuterUserId/CurrentUserId too */ |
| SetSessionUserId(roleid, AuthenticatedUserIsSuperuser); |
| |
| /* 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; |
| |
| /* |
| * 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 && !IsAutoVacuumProcess()) |
| { |
| /* |
| * 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), |
| errOmitLocation(true))); |
| |
| /* |
| * In Upgrade Mode, normal connection (i.e. dispatch mode) |
| * is disallowed unless it's the bootstrap user and |
| * gp_maintenance_conn GUC is set. |
| */ |
| if (gp_upgrade_mode && Gp_role == GP_ROLE_DISPATCH && |
| !(roleid==BOOTSTRAP_SUPERUSERID && gp_maintenance_conn)) |
| { |
| ereport(FATAL, |
| (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE), |
| errmsg("Upgrade in progress, connection refused"), |
| errOmitLocation(true), |
| errSendAlert(false))); |
| } |
| |
| /* |
| * Maintenance Mode: allow superuser to connect when |
| * gp_maintenance_conn GUC is set |
| */ |
| if (gp_maintenance_mode && Gp_role == GP_ROLE_DISPATCH && |
| !(superuser() && gp_maintenance_conn)) |
| { |
| ereport(FATAL, |
| (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE), |
| errmsg("Maintenance mode: connected by superuser only"), |
| errOmitLocation(true), |
| errSendAlert(false))); |
| } |
| |
| /* |
| * 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. |
| * |
| * We do not want to do this for QEs since a single QD might initialise |
| * many connections to each segment to execute a non-trivial plan and |
| * the user connection limit does not map, semantically, to that idea. |
| */ |
| if (Gp_role == GP_ROLE_DISPATCH && rform->rolconnlimit >= 0 && |
| !AuthenticatedUserIsSuperuser && |
| CountUserBackends(roleid) > rform->rolconnlimit) |
| ereport(FATAL, |
| (errcode(ERRCODE_TOO_MANY_CONNECTIONS), |
| errmsg("too many connections for role \"%s\"", |
| rolename), |
| errOmitLocation(true))); |
| } |
| |
| /* 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); |
| |
| /* |
| * 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 = caql_getattr(pcqCtx, |
| Anum_pg_authid_rolconfig, &isnull); |
| if (!isnull) |
| { |
| ArrayType *a = DatumGetArrayTypeP(datum); |
| |
| ProcessGUCArray(a, PGC_S_USER); |
| } |
| |
| caql_endscan(pcqCtx); |
| } |
| |
| |
| /* |
| * Initialize user identity during special backend startup |
| */ |
| void |
| InitializeSessionUserIdStandalone(void) |
| { |
| /* This function should only be called in a single-user backend. */ |
| AssertState(!IsUnderPostmaster || IsAutoVacuumProcess()); |
| |
| /* call only once */ |
| AssertState(!OidIsValid(AuthenticatedUserId)); |
| |
| AuthenticatedUserId = BOOTSTRAP_SUPERUSERID; |
| AuthenticatedUserIsSuperuser = true; |
| |
| SetSessionUserId(BOOTSTRAP_SUPERUSERID, true); |
| } |
| |
| |
| /* |
| * Change session auth ID while running |
| * |
| * Only a superuser may set auth ID to something other than himself. Note |
| * 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(Oid userid, bool is_superuser) |
| { |
| /* Must have authenticated already, else can't make permission check */ |
| AssertState(OidIsValid(AuthenticatedUserId)); |
| |
| if (userid != AuthenticatedUserId && |
| !AuthenticatedUserIsSuperuser) |
| ereport(ERROR, |
| (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE), |
| errmsg("permission denied to set session authorization"), |
| errOmitLocation(true))); |
| |
| 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; |
| |
| SetOuterUserId(roleid); |
| |
| SetConfigOption("is_superuser", |
| is_superuser ? "on" : "off", |
| PGC_INTERNAL, PGC_S_OVERRIDE); |
| } |
| |
| |
| /* |
| * Get user name from user oid |
| */ |
| char * |
| GetUserNameFromId(Oid roleid) |
| { |
| char *result; |
| int fetchCount; |
| |
| result = caql_getcstring_plus( |
| NULL, |
| &fetchCount, |
| NULL, |
| cql("SELECT rolname FROM pg_authid " |
| " WHERE oid = :1 ", |
| ObjectIdGetDatum(roleid))); |
| |
| if (!fetchCount) |
| ereport(ERROR, |
| (errcode(ERRCODE_UNDEFINED_OBJECT), |
| errmsg("invalid role OID: %u", roleid))); |
| |
| 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. |
| * |
| * On successful lockfile creation, a proc_exit callback to remove the |
| * lockfile is automatically created. |
| *------------------------------------------------------------------------- |
| */ |
| |
| /* |
| * proc_exit callback to remove a lockfile. |
| */ |
| static void |
| UnlinkLockFile(int status, Datum filename) |
| { |
| char *fname = (char *) DatumGetPointer(filename); |
| |
| if (fname != NULL) |
| { |
| if (unlink(fname) != 0) |
| { |
| /* Should we complain if the unlink fails? */ |
| } |
| free(fname); |
| } |
| } |
| |
| /* |
| * Create a lockfile. |
| * |
| * filename is the name of the lockfile to create. |
| * amPostmaster is used to determine how to encode the output PID. |
| * isDDLock and refName are used to determine what error message to produce. |
| */ |
| static void |
| CreateLockFile(const char *filename, bool amPostmaster, |
| bool isDDLock, const char *refName) |
| { |
| int fd; |
| char buffer[MAXPGPATH + 100]; |
| int ntries; |
| int len; |
| int encoded_pid; |
| pid_t other_pid; |
| pid_t my_pid = getpid(); |
| |
| /* |
| * 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) |
| break; /* Success; exit the retry loop */ |
| |
| /* |
| * Couldn't create the pid file. Probably it already exists. |
| */ |
| if ((errno != EEXIST && errno != EACCES) || ntries > 100) |
| ereport(FATAL, |
| (errcode_for_file_access(), |
| errmsg("could not create lock file \"%s\": %m", |
| filename))); |
| |
| /* |
| * Read the file to get the old owner's PID. Note race condition |
| * here: file might have been deleted since we tried to create it. |
| */ |
| fd = open(filename, O_RDONLY, 0600); |
| if (fd < 0) |
| { |
| if (errno == ENOENT) |
| continue; /* race condition; try again */ |
| ereport(FATAL, |
| (errcode_for_file_access(), |
| errmsg("could not open lock file \"%s\": %m", |
| filename))); |
| } |
| if ((len = read(fd, buffer, sizeof(buffer) - 1)) < 0) |
| ereport(FATAL, |
| (errcode_for_file_access(), |
| errmsg("could not read lock file \"%s\": %m", |
| filename))); |
| close(fd); |
| |
| buffer[len] = '\0'; |
| encoded_pid = atoi(buffer); |
| |
| /* if pid < 0, the pid is for postgres, not postmaster */ |
| other_pid = (pid_t) (encoded_pid < 0 ? -encoded_pid : encoded_pid); |
| |
| if (other_pid <= 0) |
| elog(FATAL, "bogus data in lock file \"%s\": \"%s\"", |
| filename, 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. |
| * |
| * 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.) |
| * |
| * 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 (kill(other_pid, 0) == 0 || |
| (errno != ESRCH && errno != EPERM)) |
| { |
| /* lockfile belongs to a live process */ |
| ereport(FATAL, |
| (errcode(ERRCODE_LOCK_FILE_EXISTS), |
| errmsg("lock file \"%s\" already exists", |
| filename), |
| isDDLock ? |
| (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)), |
| errOmitLocation(true))); |
| } |
| } |
| |
| /* |
| * 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. |
| */ |
| if (isDDLock) |
| { |
| char *ptr; |
| unsigned long id1, |
| id2; |
| |
| ptr = strchr(buffer, '\n'); |
| if (ptr != NULL && |
| (ptr = strchr(ptr + 1, '\n')) != NULL) |
| { |
| 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))); |
| } |
| } |
| } |
| |
| /* |
| * 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, |
| (errcode_for_file_access(), |
| errmsg("could not remove old lock file \"%s\": %m", |
| filename), |
| errhint("The file seems accidentally left over, but " |
| "it could not be removed. Please remove the file " |
| "by hand and try again."))); |
| } |
| |
| /* |
| * Successfully created the file, now fill it. |
| */ |
| snprintf(buffer, sizeof(buffer), "%d\n%s\n", |
| amPostmaster ? (int) my_pid : -((int) my_pid), |
| DataDir); |
| errno = 0; |
| if (write(fd, buffer, strlen(buffer)) != strlen(buffer)) |
| { |
| int save_errno = errno; |
| |
| close(fd); |
| unlink(filename); |
| /* if write didn't set errno, assume problem is no disk space */ |
| errno = save_errno ? save_errno : ENOSPC; |
| ereport(FATAL, |
| (errcode_for_file_access(), |
| errmsg("could not write lock file \"%s\": %m", filename))); |
| } |
| if (close(fd)) |
| { |
| 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 for automatic removal of lockfile at proc_exit. |
| */ |
| { |
| char *tmpptr = strdup(filename); |
| if(!tmpptr) |
| ereport(ERROR, (errcode(ERRCODE_OUT_OF_MEMORY), |
| errmsg("Create lock file failed: out of memory"))); |
| on_proc_exit(UnlinkLockFile, PointerGetDatum(tmpptr)); |
| } |
| } |
| |
| /* |
| * 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(bool amPostmaster) |
| { |
| CreateLockFile(DIRECTORY_LOCK_FILE, amPostmaster, true, DataDir); |
| } |
| |
| /* |
| * Create a lockfile for the specified Unix socket file. |
| */ |
| void |
| CreateSocketLockFile(const char *socketfile, bool amPostmaster) |
| { |
| char lockfile[MAXPGPATH]; |
| |
| snprintf(lockfile, sizeof(lockfile), "%s.lock", socketfile); |
| CreateLockFile(lockfile, amPostmaster, false, socketfile); |
| /* Save name of lockfile for TouchSocketLockFile */ |
| strcpy(socketLockFile, lockfile); |
| } |
| |
| /* |
| * TouchSocketLockFile -- mark socket lock file 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 |
| * from being removed by overenthusiastic /tmp-directory-cleaner daemons. |
| * (Another reason we should never have put the socket file in /tmp...) |
| */ |
| void |
| TouchSocketLockFile(void) |
| { |
| /* Do nothing if we did not create a socket... */ |
| 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. |
| */ |
| #ifdef HAVE_UTIME |
| utime(socketLockFile, NULL); |
| #else /* !HAVE_UTIME */ |
| #ifdef HAVE_UTIMES |
| utimes(socketLockFile, NULL); |
| #else /* !HAVE_UTIMES */ |
| int fd; |
| char buffer[1]; |
| |
| fd = open(socketLockFile, O_RDONLY | PG_BINARY, 0); |
| if (fd >= 0) |
| { |
| read(fd, buffer, sizeof(buffer)); |
| close(fd); |
| } |
| #endif /* HAVE_UTIMES */ |
| #endif /* HAVE_UTIME */ |
| } |
| } |
| |
| /* |
| * Append information about a shared memory segment to the data directory |
| * lock file. |
| * |
| * 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.) |
| */ |
| void |
| RecordSharedMemoryInLockFile(unsigned long id1, unsigned long id2) |
| { |
| int fd; |
| int len; |
| char *ptr; |
| char buffer[BLCKSZ]; |
| |
| fd = open(DIRECTORY_LOCK_FILE, O_RDWR | PG_BINARY, 0); |
| if (fd < 0) |
| { |
| ereport(LOG, |
| (errcode_for_file_access(), |
| errmsg("could not open file \"%s\": %m", |
| DIRECTORY_LOCK_FILE))); |
| return; |
| } |
| len = read(fd, buffer, sizeof(buffer) - 100); |
| if (len < 0) |
| { |
| ereport(LOG, |
| (errcode_for_file_access(), |
| 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). |
| */ |
| ptr = strchr(buffer, '\n'); |
| if (ptr == NULL || |
| (ptr = strchr(ptr + 1, '\n')) == NULL) |
| { |
| elog(LOG, "bogus data in \"%s\"", DIRECTORY_LOCK_FILE); |
| close(fd); |
| return; |
| } |
| ptr++; |
| |
| /* |
| * Append key information. Format to try to keep it the same length |
| * always (trailing junk won't hurt, but might confuse humans). |
| */ |
| sprintf(ptr, "%9lu %9lu\n", id1, id2); |
| |
| /* |
| * And rewrite the data. Since we write in a single kernel call, this |
| * update should appear atomic to onlookers. |
| */ |
| len = strlen(buffer); |
| errno = 0; |
| if (lseek(fd, (off_t) 0, SEEK_SET) != 0 || |
| (int) write(fd, buffer, len) != len) |
| { |
| /* if write didn't set errno, assume problem is no disk space */ |
| if (errno == 0) |
| errno = ENOSPC; |
| ereport(LOG, |
| (errcode_for_file_access(), |
| errmsg("could not write to file \"%s\": %m", |
| DIRECTORY_LOCK_FILE))); |
| close(fd); |
| return; |
| } |
| if (close(fd)) |
| { |
| ereport(LOG, |
| (errcode_for_file_access(), |
| errmsg("could not write to file \"%s\": %m", |
| DIRECTORY_LOCK_FILE))); |
| } |
| } |
| |
| |
| /*------------------------------------------------------------------------- |
| * Version checking support |
| *------------------------------------------------------------------------- |
| */ |
| |
| /* |
| * Determine whether the PG_VERSION file in directory `path' indicates |
| * a data version compatible with the version of this program. |
| * |
| * If compatible, return. Otherwise, ereport(FATAL). |
| */ |
| void |
| ValidatePgVersion(const char *path) |
| { |
| char full_path[MAXPGPATH]; |
| FILE *file; |
| int ret; |
| long file_major, |
| file_minor; |
| long my_major = 0, |
| my_minor = 0; |
| char *endptr; |
| const char *version_string = PG_VERSION; |
| |
| my_major = strtol(version_string, &endptr, 10); |
| if (*endptr == '.') |
| my_minor = strtol(endptr + 1, NULL, 10); |
| |
| snprintf(full_path, sizeof(full_path), "%s/PG_VERSION", path); |
| |
| file = AllocateFile(full_path, "r"); |
| if (!file) |
| { |
| if (errno == ENOENT) |
| ereport(FATAL, |
| (errcode(ERRCODE_INVALID_PARAMETER_VALUE), |
| errmsg("\"%s\" is not a valid data directory", |
| path), |
| errdetail("File \"%s\" is missing.", full_path))); |
| else |
| ereport(FATAL, |
| (errcode_for_file_access(), |
| errmsg("could not open file \"%s\": %m", full_path))); |
| } |
| |
| ret = fscanf(file, "%ld.%ld", &file_major, &file_minor); |
| if (ret != 2) |
| ereport(FATAL, |
| (errcode(ERRCODE_INVALID_PARAMETER_VALUE), |
| errmsg("\"%s\" is not a valid data directory", |
| path), |
| errdetail("File \"%s\" does not contain valid data.", |
| full_path), |
| errhint("You may need to run gprecoversegment.sh"))); |
| |
| FreeFile(file); |
| |
| if (my_major != file_major || my_minor != file_minor) |
| ereport(FATAL, |
| (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.", |
| file_major, file_minor, version_string))); |
| } |
| |
| /*------------------------------------------------------------------------- |
| * Library preload support |
| *------------------------------------------------------------------------- |
| */ |
| |
| /* |
| * 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; |
| |
| /* Flag telling that we are loading shared_preload_libraries */ |
| bool process_shared_preload_libraries_in_progress = false; |
| |
| /* |
| * 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/ |
| */ |
| static void |
| load_libraries(const char *libraries, const char *gucname, bool restricted) |
| { |
| char *rawstring; |
| List *elemlist; |
| int elevel; |
| ListCell *l; |
| |
| if (libraries == NULL || libraries[0] == '\0') |
| return; /* nothing to do */ |
| |
| /* Need a modifiable copy of string */ |
| rawstring = pstrdup(libraries); |
| |
| /* Parse string into list of identifiers */ |
| if (!SplitIdentifierString(rawstring, ',', &elemlist)) |
| { |
| /* syntax error in list */ |
| pfree(rawstring); |
| list_free(elemlist); |
| ereport(LOG, |
| (errcode(ERRCODE_SYNTAX_ERROR), |
| 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 *filename; |
| |
| filename = pstrdup(tok); |
| canonicalize_path(filename); |
| /* If restricting, insert $libdir/plugins if not mentioned already */ |
| if (restricted && first_dir_separator(filename) == NULL) |
| { |
| char *expanded; |
| |
| expanded = palloc(strlen("$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); |
| } |
| |
| pfree(rawstring); |
| 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 |
| } |