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Diffstat (limited to 'src/backend/utils/init/flatfiles.c')
| -rw-r--r-- | src/backend/utils/init/flatfiles.c | 931 |
1 files changed, 0 insertions, 931 deletions
diff --git a/src/backend/utils/init/flatfiles.c b/src/backend/utils/init/flatfiles.c deleted file mode 100644 index 38271653f6d..00000000000 --- a/src/backend/utils/init/flatfiles.c +++ /dev/null @@ -1,931 +0,0 @@ -/*------------------------------------------------------------------------- - * - * flatfiles.c - * Routines for maintaining "flat file" images of the shared catalogs. - * - * We use flat files so that the postmaster and not-yet-fully-started - * backends can look at the contents of pg_database, pg_authid, and - * pg_auth_members for authentication purposes. This module is - * responsible for keeping the flat-file images as nearly in sync with - * database reality as possible. - * - * The tricky part of the write_xxx_file() routines in this module is that - * they need to be able to operate in the context of the database startup - * process (which calls BuildFlatFiles()) as well as a normal backend. - * This means for example that we can't assume a fully functional relcache - * and we can't use syscaches at all. The major restriction imposed by - * all that is that there's no way to read an out-of-line-toasted datum, - * because the tuptoaster.c code is not prepared to cope with such an - * environment. Fortunately we can design the shared catalogs in such - * a way that this is OK. - * - * - * Portions Copyright (c) 1996-2009, PostgreSQL Global Development Group - * Portions Copyright (c) 1994, Regents of the University of California - * - * $PostgreSQL: pgsql/src/backend/utils/init/flatfiles.c,v 1.39 2009/08/31 02:23:22 tgl Exp $ - * - *------------------------------------------------------------------------- - */ -#include "postgres.h" - -#include <sys/stat.h> -#include <unistd.h> - -#include "access/heapam.h" -#include "access/transam.h" -#include "access/twophase_rmgr.h" -#include "access/xact.h" -#include "access/xlogutils.h" -#include "catalog/pg_auth_members.h" -#include "catalog/pg_authid.h" -#include "catalog/pg_database.h" -#include "catalog/pg_namespace.h" -#include "catalog/pg_tablespace.h" -#include "commands/trigger.h" -#include "miscadmin.h" -#include "storage/bufmgr.h" -#include "storage/fd.h" -#include "storage/lmgr.h" -#include "storage/pmsignal.h" -#include "utils/builtins.h" -#include "utils/flatfiles.h" -#include "utils/resowner.h" -#include "utils/tqual.h" - - -/* Actual names of the flat files (within $PGDATA) */ -#define DATABASE_FLAT_FILE "global/pg_database" -#define AUTH_FLAT_FILE "global/pg_auth" - -/* Info bits in a flatfiles 2PC record */ -#define FF_BIT_DATABASE 1 -#define FF_BIT_AUTH 2 - - -/* - * The need-to-update-files flags are SubTransactionIds that show - * what level of the subtransaction tree requested the update. To register - * an update, the subtransaction saves its own SubTransactionId in the flag, - * unless the value was already set to a valid SubTransactionId (which implies - * that it or a parent level has already requested the same). If it aborts - * and the value is its SubTransactionId, it resets the flag to - * InvalidSubTransactionId. If it commits, it changes the value to its - * parent's SubTransactionId. This way the value is propagated up to the - * top-level transaction, which will update the files if a valid - * SubTransactionId is seen at top-level commit. - */ -static SubTransactionId database_file_update_subid = InvalidSubTransactionId; -static SubTransactionId auth_file_update_subid = InvalidSubTransactionId; - - -/* - * Mark flat database file as needing an update (because pg_database changed) - */ -void -database_file_update_needed(void) -{ - if (database_file_update_subid == InvalidSubTransactionId) - database_file_update_subid = GetCurrentSubTransactionId(); -} - -/* - * Mark flat auth file as needing an update (because pg_authid or - * pg_auth_members changed) - */ -void -auth_file_update_needed(void) -{ - if (auth_file_update_subid == InvalidSubTransactionId) - auth_file_update_subid = GetCurrentSubTransactionId(); -} - - -/* - * database_getflatfilename --- get pathname of database file - * - * Note that result string is palloc'd, and should be freed by the caller. - * (This convention is not really needed anymore, since the relative path - * is fixed.) - */ -char * -database_getflatfilename(void) -{ - return pstrdup(DATABASE_FLAT_FILE); -} - -/* - * auth_getflatfilename --- get pathname of auth file - * - * Note that result string is palloc'd, and should be freed by the caller. - * (This convention is not really needed anymore, since the relative path - * is fixed.) - */ -char * -auth_getflatfilename(void) -{ - return pstrdup(AUTH_FLAT_FILE); -} - - -/* - * fputs_quote - * - * Outputs string in quotes, with double-quotes duplicated. - * We could use quote_ident(), but that expects a TEXT argument. - */ -static void -fputs_quote(const char *str, FILE *fp) -{ - fputc('"', fp); - while (*str) - { - fputc(*str, fp); - if (*str == '"') - fputc('"', fp); - str++; - } - fputc('"', fp); -} - -/* - * name_okay - * - * We must disallow newlines in role names because - * hba.c's parser won't handle fields split across lines, even if quoted. - */ -static bool -name_okay(const char *str) -{ - int i; - - i = strcspn(str, "\r\n"); - return (str[i] == '\0'); -} - - -/* - * write_database_file: update the flat database file - */ -static void -write_database_file(Relation drel) -{ - char *filename, - *tempname; - int bufsize; - FILE *fp; - mode_t oumask; - HeapScanDesc scan; - HeapTuple tuple; - - /* - * Create a temporary filename to be renamed later. This prevents the - * backend from clobbering the flat file while the postmaster might be - * reading from it. - */ - filename = database_getflatfilename(); - bufsize = strlen(filename) + 12; - tempname = (char *) palloc(bufsize); - snprintf(tempname, bufsize, "%s.%d", filename, MyProcPid); - - oumask = umask((mode_t) 077); - fp = AllocateFile(tempname, "w"); - umask(oumask); - if (fp == NULL) - ereport(ERROR, - (errcode_for_file_access(), - errmsg("could not write to temporary file \"%s\": %m", - tempname))); - - /* - * Read pg_database and write the file. - */ - scan = heap_beginscan(drel, SnapshotNow, 0, NULL); - while ((tuple = heap_getnext(scan, ForwardScanDirection)) != NULL) - { - Form_pg_database dbform = (Form_pg_database) GETSTRUCT(tuple); - char *datname; - Oid datoid; - Oid dattablespace; - TransactionId datfrozenxid; - - datname = NameStr(dbform->datname); - datoid = HeapTupleGetOid(tuple); - dattablespace = dbform->dattablespace; - datfrozenxid = dbform->datfrozenxid; - - /* - * Check for illegal characters in the database name. - */ - if (!name_okay(datname)) - { - ereport(LOG, - (errmsg("invalid database name \"%s\"", datname))); - continue; - } - - /* - * The file format is: "dbname" oid tablespace frozenxid - * - * The xids are not needed for backend startup, but are of use to - * autovacuum, and might also be helpful for forensic purposes. - */ - fputs_quote(datname, fp); - fprintf(fp, " %u %u %u\n", - datoid, dattablespace, datfrozenxid); - } - heap_endscan(scan); - - if (FreeFile(fp)) - ereport(ERROR, - (errcode_for_file_access(), - errmsg("could not write to temporary file \"%s\": %m", - tempname))); - - /* - * Rename the temp file to its final name, deleting the old flat file. We - * expect that rename(2) is an atomic action. - */ - if (rename(tempname, filename)) - ereport(ERROR, - (errcode_for_file_access(), - errmsg("could not rename file \"%s\" to \"%s\": %m", - tempname, filename))); -} - - -/* - * Support for write_auth_file - * - * The format for the flat auth file is - * "rolename" "password" "validuntil" "memberof" "memberof" ... - * Each role's line lists all the roles (groups) of which it is directly - * or indirectly a member, except for itself. - * - * The postmaster expects the file to be sorted by rolename. There is not - * any special ordering of the membership lists. - * - * To construct this information, we scan pg_authid and pg_auth_members, - * and build data structures in-memory before writing the file. - */ - -typedef struct -{ - Oid roleid; - char *rolname; - char *rolpassword; - char *rolvaliduntil; - List *member_of; -} auth_entry; - -typedef struct -{ - Oid roleid; - Oid memberid; -} authmem_entry; - - -/* qsort comparator for sorting auth_entry array by roleid */ -static int -oid_compar(const void *a, const void *b) -{ - const auth_entry *a_auth = (const auth_entry *) a; - const auth_entry *b_auth = (const auth_entry *) b; - - if (a_auth->roleid < b_auth->roleid) - return -1; - if (a_auth->roleid > b_auth->roleid) - return 1; - return 0; -} - -/* qsort comparator for sorting auth_entry array by rolname */ -static int -name_compar(const void *a, const void *b) -{ - const auth_entry *a_auth = (const auth_entry *) a; - const auth_entry *b_auth = (const auth_entry *) b; - - return strcmp(a_auth->rolname, b_auth->rolname); -} - -/* qsort comparator for sorting authmem_entry array by memberid */ -static int -mem_compar(const void *a, const void *b) -{ - const authmem_entry *a_auth = (const authmem_entry *) a; - const authmem_entry *b_auth = (const authmem_entry *) b; - - if (a_auth->memberid < b_auth->memberid) - return -1; - if (a_auth->memberid > b_auth->memberid) - return 1; - return 0; -} - - -/* - * write_auth_file: update the flat auth file - */ -static void -write_auth_file(Relation rel_authid, Relation rel_authmem) -{ - char *filename, - *tempname; - int bufsize; - BlockNumber totalblocks; - FILE *fp; - mode_t oumask; - HeapScanDesc scan; - HeapTuple tuple; - int curr_role = 0; - int total_roles = 0; - int curr_mem = 0; - int total_mem = 0; - int est_rows; - auth_entry *auth_info; - authmem_entry *authmem_info; - - /* - * Create a temporary filename to be renamed later. This prevents the - * backend from clobbering the flat file while the postmaster might be - * reading from it. - */ - filename = auth_getflatfilename(); - bufsize = strlen(filename) + 12; - tempname = (char *) palloc(bufsize); - snprintf(tempname, bufsize, "%s.%d", filename, MyProcPid); - - oumask = umask((mode_t) 077); - fp = AllocateFile(tempname, "w"); - umask(oumask); - if (fp == NULL) - ereport(ERROR, - (errcode_for_file_access(), - errmsg("could not write to temporary file \"%s\": %m", - tempname))); - - /* - * Read pg_authid and fill temporary data structures. - */ - totalblocks = RelationGetNumberOfBlocks(rel_authid); - totalblocks = totalblocks ? totalblocks : 1; - est_rows = totalblocks * (BLCKSZ / (sizeof(HeapTupleHeaderData) + sizeof(FormData_pg_authid))); - auth_info = (auth_entry *) palloc(est_rows * sizeof(auth_entry)); - - scan = heap_beginscan(rel_authid, SnapshotNow, 0, NULL); - while ((tuple = heap_getnext(scan, ForwardScanDirection)) != NULL) - { - Form_pg_authid aform = (Form_pg_authid) GETSTRUCT(tuple); - HeapTupleHeader tup = tuple->t_data; - char *tp; /* ptr to tuple data */ - long off; /* offset in tuple data */ - bits8 *bp = tup->t_bits; /* ptr to null bitmask in tuple */ - Datum datum; - - if (curr_role >= est_rows) - { - est_rows *= 2; - auth_info = (auth_entry *) - repalloc(auth_info, est_rows * sizeof(auth_entry)); - } - - auth_info[curr_role].roleid = HeapTupleGetOid(tuple); - auth_info[curr_role].rolname = pstrdup(NameStr(aform->rolname)); - auth_info[curr_role].member_of = NIL; - - /* - * We can't use heap_getattr() here because during startup we will not - * have any tupdesc for pg_authid. Fortunately it's not too hard to - * work around this. rolpassword is the first possibly-null field so - * we can compute its offset directly. Note that this only works - * reliably because the preceding field (rolconnlimit) is int4, and - * therefore rolpassword is always 4-byte-aligned, and will be at the - * same offset no matter whether it uses 1-byte or 4-byte header. - */ - tp = (char *) tup + tup->t_hoff; - off = offsetof(FormData_pg_authid, rolpassword); - - if (HeapTupleHasNulls(tuple) && - att_isnull(Anum_pg_authid_rolpassword - 1, bp)) - { - /* passwd is null, emit as an empty string */ - auth_info[curr_role].rolpassword = pstrdup(""); - } - else - { - /* assume passwd is pass-by-ref */ - datum = PointerGetDatum(tp + off); - - /* - * The password probably shouldn't ever be out-of-line toasted; if - * it is, ignore it, since we can't handle that in startup mode. - * - * It is entirely likely that it's 1-byte format not 4-byte, and - * theoretically possible that it's compressed inline, but - * text_to_cstring should be able to handle those cases even in - * startup mode. - */ - if (VARATT_IS_EXTERNAL(DatumGetPointer(datum))) - auth_info[curr_role].rolpassword = pstrdup(""); - else - auth_info[curr_role].rolpassword = TextDatumGetCString(datum); - - /* assume passwd has attlen -1 */ - off = att_addlength_pointer(off, -1, tp + off); - } - - if (HeapTupleHasNulls(tuple) && - att_isnull(Anum_pg_authid_rolvaliduntil - 1, bp)) - { - /* rolvaliduntil is null, emit as an empty string */ - auth_info[curr_role].rolvaliduntil = pstrdup(""); - } - else - { - TimestampTz *rvup; - - /* Assume timestamptz has double alignment */ - off = att_align_nominal(off, 'd'); - rvup = (TimestampTz *) (tp + off); - auth_info[curr_role].rolvaliduntil = - DatumGetCString(DirectFunctionCall1(timestamptz_out, - TimestampTzGetDatum(*rvup))); - } - - /* - * Check for illegal characters in the user name and password. - */ - if (!name_okay(auth_info[curr_role].rolname)) - { - ereport(LOG, - (errmsg("invalid role name \"%s\"", - auth_info[curr_role].rolname))); - continue; - } - if (!name_okay(auth_info[curr_role].rolpassword)) - { - ereport(LOG, - (errmsg("invalid role password \"%s\"", - auth_info[curr_role].rolpassword))); - continue; - } - - curr_role++; - total_roles++; - } - heap_endscan(scan); - - /* - * Read pg_auth_members into temporary data structure, too - */ - totalblocks = RelationGetNumberOfBlocks(rel_authmem); - totalblocks = totalblocks ? totalblocks : 1; - est_rows = totalblocks * (BLCKSZ / (sizeof(HeapTupleHeaderData) + sizeof(FormData_pg_auth_members))); - authmem_info = (authmem_entry *) palloc(est_rows * sizeof(authmem_entry)); - - scan = heap_beginscan(rel_authmem, SnapshotNow, 0, NULL); - while ((tuple = heap_getnext(scan, ForwardScanDirection)) != NULL) - { - Form_pg_auth_members memform = (Form_pg_auth_members) GETSTRUCT(tuple); - - if (curr_mem >= est_rows) - { - est_rows *= 2; - authmem_info = (authmem_entry *) - repalloc(authmem_info, est_rows * sizeof(authmem_entry)); - } - - authmem_info[curr_mem].roleid = memform->roleid; - authmem_info[curr_mem].memberid = memform->member; - curr_mem++; - total_mem++; - } - heap_endscan(scan); - - /* - * Search for memberships. We can skip all this if pg_auth_members is - * empty. - */ - if (total_mem > 0) - { - /* - * Sort auth_info by roleid and authmem_info by memberid. - */ - qsort(auth_info, total_roles, sizeof(auth_entry), oid_compar); - qsort(authmem_info, total_mem, sizeof(authmem_entry), mem_compar); - - /* - * For each role, find what it belongs to. - */ - for (curr_role = 0; curr_role < total_roles; curr_role++) - { - List *roles_list; - List *roles_names_list = NIL; - ListCell *mem; - - /* - * This search algorithm is the same as in is_member_of_role; we - * are just working with a different input data structure. - */ - roles_list = list_make1_oid(auth_info[curr_role].roleid); - - foreach(mem, roles_list) - { - authmem_entry key; - authmem_entry *found_mem; - int first_found, - last_found, - i; - - key.memberid = lfirst_oid(mem); - found_mem = bsearch(&key, authmem_info, total_mem, - sizeof(authmem_entry), mem_compar); - if (!found_mem) - continue; - - /* - * bsearch found a match for us; but if there were multiple - * matches it could have found any one of them. Locate first - * and last match. - */ - first_found = last_found = (found_mem - authmem_info); - while (first_found > 0 && - mem_compar(&key, &authmem_info[first_found - 1]) == 0) - first_found--; - while (last_found + 1 < total_mem && - mem_compar(&key, &authmem_info[last_found + 1]) == 0) - last_found++; - - /* - * Now add all the new roles to roles_list. - */ - for (i = first_found; i <= last_found; i++) - roles_list = list_append_unique_oid(roles_list, - authmem_info[i].roleid); - } - - /* - * Convert list of role Oids to list of role names. We must do - * this before re-sorting auth_info. - * - * We skip the first list element (curr_role itself) since there - * is no point in writing that a role is a member of itself. - */ - for_each_cell(mem, lnext(list_head(roles_list))) - { - auth_entry key_auth; - auth_entry *found_role; - - key_auth.roleid = lfirst_oid(mem); - found_role = bsearch(&key_auth, auth_info, total_roles, - sizeof(auth_entry), oid_compar); - if (found_role) /* paranoia */ - roles_names_list = lappend(roles_names_list, - found_role->rolname); - } - auth_info[curr_role].member_of = roles_names_list; - list_free(roles_list); - } - } - - /* - * Now sort auth_info into rolname order for output, and write the file. - */ - qsort(auth_info, total_roles, sizeof(auth_entry), name_compar); - - for (curr_role = 0; curr_role < total_roles; curr_role++) - { - auth_entry *arole = &auth_info[curr_role]; - ListCell *mem; - - fputs_quote(arole->rolname, fp); - fputs(" ", fp); - fputs_quote(arole->rolpassword, fp); - fputs(" ", fp); - fputs_quote(arole->rolvaliduntil, fp); - - foreach(mem, arole->member_of) - { - fputs(" ", fp); - fputs_quote((char *) lfirst(mem), fp); - } - - fputs("\n", fp); - } - - if (FreeFile(fp)) - ereport(ERROR, - (errcode_for_file_access(), - errmsg("could not write to temporary file \"%s\": %m", - tempname))); - - /* - * Rename the temp file to its final name, deleting the old flat file. We - * expect that rename(2) is an atomic action. - */ - if (rename(tempname, filename)) - ereport(ERROR, - (errcode_for_file_access(), - errmsg("could not rename file \"%s\" to \"%s\": %m", - tempname, filename))); -} - - -/* - * This routine is called once during database startup, after completing - * WAL replay if needed. Its purpose is to sync the flat files with the - * current state of the database tables. This is particularly important - * during PITR operation, since the flat files will come from the - * base backup which may be far out of sync with the current state. - * - * In theory we could skip rebuilding the flat files if no WAL replay - * occurred, but it seems best to just do it always. We have to - * scan pg_database to compute the XID wrap limit anyway. Also, this - * policy means we need not force initdb to change the format of the - * flat files. - * - * In a standalone backend we pass database_only = true to skip processing - * the auth file. We won't need it, and building it could fail if there's - * something corrupt in the authid/authmem catalogs. - */ -void -BuildFlatFiles(bool database_only) -{ - ResourceOwner owner; - RelFileNode rnode; - Relation rel_db, - rel_authid, - rel_authmem; - - /* Need a resowner to keep the heapam and buffer code happy */ - owner = ResourceOwnerCreate(NULL, "BuildFlatFiles"); - CurrentResourceOwner = owner; - - /* hard-wired path to pg_database */ - rnode.spcNode = GLOBALTABLESPACE_OID; - rnode.dbNode = 0; - rnode.relNode = DatabaseRelationId; - - /* - * We don't have any hope of running a real relcache, but we can use the - * same fake-relcache facility that WAL replay uses. - * - * No locking is needed because no one else is alive yet. - */ - rel_db = CreateFakeRelcacheEntry(rnode); - write_database_file(rel_db); - FreeFakeRelcacheEntry(rel_db); - - if (!database_only) - { - /* hard-wired path to pg_authid */ - rnode.spcNode = GLOBALTABLESPACE_OID; - rnode.dbNode = 0; - rnode.relNode = AuthIdRelationId; - rel_authid = CreateFakeRelcacheEntry(rnode); - - /* hard-wired path to pg_auth_members */ - rnode.spcNode = GLOBALTABLESPACE_OID; - rnode.dbNode = 0; - rnode.relNode = AuthMemRelationId; - rel_authmem = CreateFakeRelcacheEntry(rnode); - - write_auth_file(rel_authid, rel_authmem); - FreeFakeRelcacheEntry(rel_authid); - FreeFakeRelcacheEntry(rel_authmem); - } - - CurrentResourceOwner = NULL; - ResourceOwnerDelete(owner); -} - - -/* - * This routine is called during transaction commit or abort. - * - * On commit, if we've written any of the critical database tables during - * the current transaction, update the flat files and signal the postmaster. - * - * On abort, just reset the static flags so we don't try to do it on the - * next successful commit. - * - * NB: this should be the last step before actual transaction commit. - * If any error aborts the transaction after we run this code, the postmaster - * will still have received and cached the changed data; so minimize the - * window for such problems. - */ -void -AtEOXact_UpdateFlatFiles(bool isCommit) -{ - Relation drel = NULL; - Relation arel = NULL; - Relation mrel = NULL; - - if (database_file_update_subid == InvalidSubTransactionId && - auth_file_update_subid == InvalidSubTransactionId) - return; /* nothing to do */ - - if (!isCommit) - { - database_file_update_subid = InvalidSubTransactionId; - auth_file_update_subid = InvalidSubTransactionId; - return; - } - - /* - * Advance command counter to be certain we see all effects of the current - * transaction. - */ - CommandCounterIncrement(); - - /* - * Open and lock the needed catalog(s). - * - * Even though we only need AccessShareLock, this could theoretically fail - * due to deadlock. In practice, however, our transaction already holds - * RowExclusiveLock or better (it couldn't have updated the catalog - * without such a lock). This implies that dbcommands.c and other places - * that force flat-file updates must not follow the common practice of - * dropping catalog locks before commit. - */ - if (database_file_update_subid != InvalidSubTransactionId) - drel = heap_open(DatabaseRelationId, AccessShareLock); - - if (auth_file_update_subid != InvalidSubTransactionId) - { - arel = heap_open(AuthIdRelationId, AccessShareLock); - mrel = heap_open(AuthMemRelationId, AccessShareLock); - } - - /* - * Obtain special locks to ensure that two transactions don't try to write - * the same flat file concurrently. Quite aside from any direct risks of - * corrupted output, the winning writer probably wouldn't have seen the - * other writer's updates. By taking a lock and holding it till commit, - * we ensure that whichever updater goes second will see the other - * updater's changes as committed, and thus the final state of the file - * will include all updates. - * - * We use a lock on "database 0" to protect writing the pg_database flat - * file, and a lock on "role 0" to protect the auth file. This is a bit - * ugly but it's not worth inventing any more-general convention. (Any - * two locktags that are never used for anything else would do.) - * - * This is safe against deadlock as long as these are the very last locks - * acquired during the transaction. - */ - if (database_file_update_subid != InvalidSubTransactionId) - LockSharedObject(DatabaseRelationId, InvalidOid, 0, - AccessExclusiveLock); - - if (auth_file_update_subid != InvalidSubTransactionId) - LockSharedObject(AuthIdRelationId, InvalidOid, 0, - AccessExclusiveLock); - - /* Okay to write the files */ - if (database_file_update_subid != InvalidSubTransactionId) - { - database_file_update_subid = InvalidSubTransactionId; - write_database_file(drel); - heap_close(drel, NoLock); - } - - if (auth_file_update_subid != InvalidSubTransactionId) - { - auth_file_update_subid = InvalidSubTransactionId; - write_auth_file(arel, mrel); - heap_close(arel, NoLock); - heap_close(mrel, NoLock); - } - - /* - * Force synchronous commit, to minimize the window between changing the - * flat files on-disk and marking the transaction committed. It's not - * great that there is any window at all, but definitely we don't want to - * make it larger than necessary. - */ - ForceSyncCommit(); -} - - -/* - * This routine is called during transaction prepare. - * - * Record which files need to be refreshed if this transaction later - * commits. - * - * Note: it's OK to clear the flags immediately, since if the PREPARE fails - * further on, we'd only reset the flags anyway. So there's no need for a - * separate PostPrepare call. - */ -void -AtPrepare_UpdateFlatFiles(void) -{ - uint16 info = 0; - - if (database_file_update_subid != InvalidSubTransactionId) - { - database_file_update_subid = InvalidSubTransactionId; - info |= FF_BIT_DATABASE; - } - if (auth_file_update_subid != InvalidSubTransactionId) - { - auth_file_update_subid = InvalidSubTransactionId; - info |= FF_BIT_AUTH; - } - if (info != 0) - RegisterTwoPhaseRecord(TWOPHASE_RM_FLATFILES_ID, info, - NULL, 0); -} - - -/* - * AtEOSubXact_UpdateFlatFiles - * - * Called at subtransaction end, this routine resets or updates the - * need-to-update-files flags. - */ -void -AtEOSubXact_UpdateFlatFiles(bool isCommit, - SubTransactionId mySubid, - SubTransactionId parentSubid) -{ - if (isCommit) - { - if (database_file_update_subid == mySubid) - database_file_update_subid = parentSubid; - - if (auth_file_update_subid == mySubid) - auth_file_update_subid = parentSubid; - } - else - { - if (database_file_update_subid == mySubid) - database_file_update_subid = InvalidSubTransactionId; - - if (auth_file_update_subid == mySubid) - auth_file_update_subid = InvalidSubTransactionId; - } -} - - -/* - * This trigger is fired whenever someone modifies pg_database, pg_authid - * or pg_auth_members via general-purpose INSERT/UPDATE/DELETE commands. - * - * It is sufficient for this to be a STATEMENT trigger since we don't - * care which individual rows changed. It doesn't much matter whether - * it's a BEFORE or AFTER trigger. - */ -Datum -flatfile_update_trigger(PG_FUNCTION_ARGS) -{ - TriggerData *trigdata = (TriggerData *) fcinfo->context; - - if (!CALLED_AS_TRIGGER(fcinfo)) - elog(ERROR, - "flatfile_update_trigger was not called by trigger manager"); - - if (RelationGetNamespace(trigdata->tg_relation) != PG_CATALOG_NAMESPACE) - elog(ERROR, "flatfile_update_trigger was called for wrong table"); - - switch (RelationGetRelid(trigdata->tg_relation)) - { - case DatabaseRelationId: - database_file_update_needed(); - break; - case AuthIdRelationId: - case AuthMemRelationId: - auth_file_update_needed(); - break; - default: - elog(ERROR, "flatfile_update_trigger was called for wrong table"); - break; - } - - return PointerGetDatum(NULL); -} - - -/* - * 2PC processing routine for COMMIT PREPARED case. - * - * (We don't have to do anything for ROLLBACK PREPARED.) - */ -void -flatfile_twophase_postcommit(TransactionId xid, uint16 info, - void *recdata, uint32 len) -{ - /* - * Set flags to do the needed file updates at the end of my own current - * transaction. (XXX this has some issues if my own transaction later - * rolls back, or if there is any significant delay before I commit. OK - * for now because we disallow COMMIT PREPARED inside a transaction - * block.) - */ - if (info & FF_BIT_DATABASE) - database_file_update_needed(); - if (info & FF_BIT_AUTH) - auth_file_update_needed(); -} |