Add WAL logging for CREATE/DROP DATABASE and CREATE/DROP TABLESPACE.

[postgresql] / src / backend / commands / dbcommands.c

diff --git a/src/backend/commands/dbcommands.c b/src/backend/commands/dbcommands.c
index f7ef440b02e7774799a527b40a4024c5a8afec7f..aa95d97d0e29e01e1dd126fe9586a72d30a67d91 100644 (file)
--- a/src/backend/commands/dbcommands.c
+++ b/src/backend/commands/dbcommands.c
@@ -9,7 +9,7 @@
  *
  *
  * IDENTIFICATION
- *       $PostgreSQL: pgsql/src/backend/commands/dbcommands.c,v 1.141 2004/08/29 05:06:41 momjian Exp $
+ *       $PostgreSQL: pgsql/src/backend/commands/dbcommands.c,v 1.142 2004/08/29 21:08:47 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -385,6 +385,30 @@ createdb(const CreatedbStmt *stmt)
                                        (errmsg("could not initialize database directory")));
                }
 #endif   /* WIN32 */
+
+               /* Record the filesystem change in XLOG */
+               {
+                       xl_dbase_create_rec xlrec;
+                       XLogRecData rdata[3];
+
+                       xlrec.db_id = dboid;
+                       rdata[0].buffer = InvalidBuffer;
+                       rdata[0].data = (char *) &xlrec;
+                       rdata[0].len = offsetof(xl_dbase_create_rec, src_path);
+                       rdata[0].next = &(rdata[1]);
+
+                       rdata[1].buffer = InvalidBuffer;
+                       rdata[1].data = (char *) srcpath;
+                       rdata[1].len = strlen(srcpath) + 1;
+                       rdata[1].next = &(rdata[2]);
+
+                       rdata[2].buffer = InvalidBuffer;
+                       rdata[2].data = (char *) dstpath;
+                       rdata[2].len = strlen(dstpath) + 1;
+                       rdata[2].next = NULL;
+
+                       (void) XLogInsert(RM_DBASE_ID, XLOG_DBASE_CREATE, rdata);
+               }
        }
        heap_endscan(scan);
        heap_close(rel, AccessShareLock);
@@ -970,11 +994,27 @@ remove_dbtablespaces(Oid db_id)
                }
 
                if (!rmtree(dstpath, true))
-               {
                        ereport(WARNING,
                                        (errmsg("could not remove database directory \"%s\"",
-                                                       dstpath),
-                                        errhint("Look in the postmaster's stderr log for more information.")));
+                                                       dstpath)));
+
+               /* Record the filesystem change in XLOG */
+               {
+                       xl_dbase_drop_rec xlrec;
+                       XLogRecData rdata[2];
+
+                       xlrec.db_id = db_id;
+                       rdata[0].buffer = InvalidBuffer;
+                       rdata[0].data = (char *) &xlrec;
+                       rdata[0].len = offsetof(xl_dbase_drop_rec, dir_path);
+                       rdata[0].next = &(rdata[1]);
+
+                       rdata[1].buffer = InvalidBuffer;
+                       rdata[1].data = (char *) dstpath;
+                       rdata[1].len = strlen(dstpath) + 1;
+                       rdata[1].next = NULL;
+
+                       (void) XLogInsert(RM_DBASE_ID, XLOG_DBASE_DROP, rdata);
                }
 
                pfree(dstpath);
@@ -1063,3 +1103,105 @@ get_database_name(Oid dbid)
 
        return result;
 }
+
+/*
+ * DATABASE resource manager's routines
+ */
+void
+dbase_redo(XLogRecPtr lsn, XLogRecord *record)
+{
+       uint8           info = record->xl_info & ~XLR_INFO_MASK;
+
+       if (info == XLOG_DBASE_CREATE)
+       {
+               xl_dbase_create_rec *xlrec = (xl_dbase_create_rec *) XLogRecGetData(record);
+               char       *dst_path = xlrec->src_path + strlen(xlrec->src_path) + 1;
+               struct stat st;
+#ifndef WIN32
+               char            buf[2 * MAXPGPATH + 100];
+#endif
+
+               /*
+                * Our theory for replaying a CREATE is to forcibly drop the target
+                * subdirectory if present, then re-copy the source data.  This
+                * may be more work than needed, but it is simple to implement.
+                */
+               if (stat(dst_path, &st) == 0 && S_ISDIR(st.st_mode))
+               {
+                       if (!rmtree(dst_path, true))
+                               ereport(WARNING,
+                                               (errmsg("could not remove database directory \"%s\"",
+                                                               dst_path)));
+               }
+
+#ifndef WIN32
+               /*
+                * Copy this subdirectory to the new location
+                *
+                * XXX use of cp really makes this code pretty grotty, particularly
+                * with respect to lack of ability to report errors well.  Someday
+                * rewrite to do it for ourselves.
+                */
+
+               /* We might need to use cp -R one day for portability */
+               snprintf(buf, sizeof(buf), "cp -r '%s' '%s'",
+                                xlrec->src_path, dst_path);
+               if (system(buf) != 0)
+                       ereport(ERROR,
+                                       (errmsg("could not initialize database directory"),
+                                        errdetail("Failing system command was: %s", buf),
+                                        errhint("Look in the postmaster's stderr log for more information.")));
+#else                                                  /* WIN32 */
+               if (copydir(xlrec->src_path, dst_path) != 0)
+               {
+                       /* copydir should already have given details of its troubles */
+                       ereport(ERROR,
+                                       (errmsg("could not initialize database directory")));
+               }
+#endif   /* WIN32 */
+       }
+       else if (info == XLOG_DBASE_DROP)
+       {
+               xl_dbase_drop_rec *xlrec = (xl_dbase_drop_rec *) XLogRecGetData(record);
+
+               /* Drop pages for this database that are in the shared buffer cache */
+               DropBuffers(xlrec->db_id);
+
+               if (!rmtree(xlrec->dir_path, true))
+                       ereport(WARNING,
+                                       (errmsg("could not remove database directory \"%s\"",
+                                                       xlrec->dir_path)));
+       }
+       else
+               elog(PANIC, "dbase_redo: unknown op code %u", info);
+}
+
+void
+dbase_undo(XLogRecPtr lsn, XLogRecord *record)
+{
+       elog(PANIC, "dbase_undo: unimplemented");
+}
+
+void
+dbase_desc(char *buf, uint8 xl_info, char *rec)
+{
+       uint8           info = xl_info & ~XLR_INFO_MASK;
+
+       if (info == XLOG_DBASE_CREATE)
+       {
+               xl_dbase_create_rec *xlrec = (xl_dbase_create_rec *) rec;
+               char       *dst_path = xlrec->src_path + strlen(xlrec->src_path) + 1;
+
+               sprintf(buf + strlen(buf), "create db: %u copy \"%s\" to \"%s\"",
+                               xlrec->db_id, xlrec->src_path, dst_path);
+       }
+       else if (info == XLOG_DBASE_DROP)
+       {
+               xl_dbase_drop_rec *xlrec = (xl_dbase_drop_rec *) rec;
+
+               sprintf(buf + strlen(buf), "drop db: %u directory: \"%s\"",
+                               xlrec->db_id, xlrec->dir_path);
+       }
+       else
+               strcat(buf, "UNKNOWN");
+}