diff --git a/src/backend/access/nbtree/nbtree.c b/src/backend/access/nbtree/nbtree.c
index 24f9b4c77b21ca1d2cbff8c492862c8ed61fde06..06278afc6af1317297a5d95d21ab0e8011c11561 100644
--- a/src/backend/access/nbtree/nbtree.c
+++ b/src/backend/access/nbtree/nbtree.c
@@ -12,7 +12,7 @@
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/access/nbtree/nbtree.c,v 1.158 2008/04/13 19:18:14 tgl Exp $
+ * $PostgreSQL: pgsql/src/backend/access/nbtree/nbtree.c,v 1.159 2008/04/16 23:59:39 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -24,6 +24,7 @@
#include "commands/vacuum.h"
#include "miscadmin.h"
#include "storage/freespace.h"
+#include "storage/ipc.h"
#include "storage/lmgr.h"
#include "utils/memutils.h"
@@ -530,21 +531,15 @@ btbulkdelete(PG_FUNCTION_ARGS)
stats = (IndexBulkDeleteResult *) palloc0(sizeof(IndexBulkDeleteResult));
/* Establish the vacuum cycle ID to use for this scan */
- PG_TRY();
+ /* The ENSURE stuff ensures we clean up shared memory on failure */
+ PG_ENSURE_ERROR_CLEANUP(_bt_end_vacuum_callback, PointerGetDatum(rel));
{
cycleid = _bt_start_vacuum(rel);
btvacuumscan(info, stats, callback, callback_state, cycleid);
-
- _bt_end_vacuum(rel);
- }
- PG_CATCH();
- {
- /* Make sure shared memory gets cleaned up */
- _bt_end_vacuum(rel);
- PG_RE_THROW();
}
- PG_END_TRY();
+ PG_END_ENSURE_ERROR_CLEANUP(_bt_end_vacuum_callback, PointerGetDatum(rel));
+ _bt_end_vacuum(rel);
PG_RETURN_POINTER(stats);
}
diff --git a/src/backend/access/nbtree/nbtutils.c b/src/backend/access/nbtree/nbtutils.c
index 6f88a34488e2f050cf3fd2df24f3777421aa137b..6759ce6f2b2dd37215f45e0ffb17fb8eae92248e 100644
--- a/src/backend/access/nbtree/nbtutils.c
+++ b/src/backend/access/nbtree/nbtutils.c
@@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/access/nbtree/nbtutils.c,v 1.88 2008/01/01 19:45:46 momjian Exp $
+ * $PostgreSQL: pgsql/src/backend/access/nbtree/nbtutils.c,v 1.89 2008/04/16 23:59:40 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -1252,8 +1252,11 @@ _bt_vacuum_cycleid(Relation rel)
/*
* _bt_start_vacuum --- assign a cycle ID to a just-starting VACUUM operation
*
- * Note: the caller must guarantee (via PG_TRY) that it will eventually call
- * _bt_end_vacuum, else we'll permanently leak an array slot.
+ * Note: the caller must guarantee that it will eventually call
+ * _bt_end_vacuum, else we'll permanently leak an array slot. To ensure
+ * that this happens even in elog(FATAL) scenarios, the appropriate coding
+ * is not just a PG_TRY, but
+ * PG_ENSURE_ERROR_CLEANUP(_bt_end_vacuum_callback, PointerGetDatum(rel))
*/
BTCycleId
_bt_start_vacuum(Relation rel)
@@ -1337,6 +1340,15 @@ _bt_end_vacuum(Relation rel)
LWLockRelease(BtreeVacuumLock);
}
+/*
+ * _bt_end_vacuum wrapped as an on_shmem_exit callback function
+ */
+void
+_bt_end_vacuum_callback(int code, Datum arg)
+{
+ _bt_end_vacuum((Relation) DatumGetPointer(arg));
+}
+
/*
* BTreeShmemSize --- report amount of shared memory space needed
*/
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index b059e49bc3dfc5598704904ac4c85c7e89ab3c33..bb8f3d4761f37cfb847467dd3b50dc6591cc0f1f 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -7,7 +7,7 @@
* Portions Copyright (c) 1996-2008, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
- * $PostgreSQL: pgsql/src/backend/access/transam/xlog.c,v 1.296 2008/04/05 01:34:06 momjian Exp $
+ * $PostgreSQL: pgsql/src/backend/access/transam/xlog.c,v 1.297 2008/04/16 23:59:40 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -43,6 +43,7 @@
#include "postmaster/bgwriter.h"
#include "storage/bufpage.h"
#include "storage/fd.h"
+#include "storage/ipc.h"
#include "storage/pmsignal.h"
#include "storage/procarray.h"
#include "storage/smgr.h"
@@ -419,11 +420,11 @@ static void writeTimeLineHistory(TimeLineID newTLI, TimeLineID parentTLI,
static void WriteControlFile(void);
static void ReadControlFile(void);
static char *str_time(pg_time_t tnow);
-static void issue_xlog_fsync(void);
-
#ifdef WAL_DEBUG
static void xlog_outrec(StringInfo buf, XLogRecord *record);
#endif
+static void issue_xlog_fsync(void);
+static void pg_start_backup_callback(int code, Datum arg);
static bool read_backup_label(XLogRecPtr *checkPointLoc,
XLogRecPtr *minRecoveryLoc);
static void rm_redo_error_callback(void *arg);
@@ -6442,8 +6443,8 @@ pg_start_backup(PG_FUNCTION_ARGS)
XLogCtl->Insert.forcePageWrites = true;
LWLockRelease(WALInsertLock);
- /* Use a TRY block to ensure we release forcePageWrites if fail below */
- PG_TRY();
+ /* Ensure we release forcePageWrites if fail below */
+ PG_ENSURE_ERROR_CLEANUP(pg_start_backup_callback, (Datum) 0);
{
/*
* Force a CHECKPOINT. Aside from being necessary to prevent torn
@@ -6515,16 +6516,7 @@ pg_start_backup(PG_FUNCTION_ARGS)
errmsg("could not write file \"%s\": %m",
BACKUP_LABEL_FILE)));
}
- PG_CATCH();
- {
- /* Turn off forcePageWrites on failure */
- LWLockAcquire(WALInsertLock, LW_EXCLUSIVE);
- XLogCtl->Insert.forcePageWrites = false;
- LWLockRelease(WALInsertLock);
-
- PG_RE_THROW();
- }
- PG_END_TRY();
+ PG_END_ENSURE_ERROR_CLEANUP(pg_start_backup_callback, (Datum) 0);
/*
* We're done. As a convenience, return the starting WAL location.
@@ -6534,6 +6526,16 @@ pg_start_backup(PG_FUNCTION_ARGS)
PG_RETURN_TEXT_P(cstring_to_text(xlogfilename));
}
+/* Error cleanup callback for pg_start_backup */
+static void
+pg_start_backup_callback(int code, Datum arg)
+{
+ /* Turn off forcePageWrites on failure */
+ LWLockAcquire(WALInsertLock, LW_EXCLUSIVE);
+ XLogCtl->Insert.forcePageWrites = false;
+ LWLockRelease(WALInsertLock);
+}
+
/*
* pg_stop_backup: finish taking an on-line backup dump
*
diff --git a/src/backend/commands/dbcommands.c b/src/backend/commands/dbcommands.c
index b7bd041e3a24e9bd868e49145a69c22637e1086f..857db388a8fe8251cdb92de583585e9ffa84b2a8 100644
--- a/src/backend/commands/dbcommands.c
+++ b/src/backend/commands/dbcommands.c
@@ -13,7 +13,7 @@
*
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/commands/dbcommands.c,v 1.205 2008/03/26 21:10:37 alvherre Exp $
+ * $PostgreSQL: pgsql/src/backend/commands/dbcommands.c,v 1.206 2008/04/16 23:59:40 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -41,6 +41,7 @@
#include "pgstat.h"
#include "postmaster/bgwriter.h"
#include "storage/freespace.h"
+#include "storage/ipc.h"
#include "storage/procarray.h"
#include "storage/smgr.h"
#include "utils/acl.h"
@@ -53,7 +54,14 @@
#include "utils/tqual.h"
+typedef struct
+{
+ Oid src_dboid; /* source (template) DB */
+ Oid dest_dboid; /* DB we are trying to create */
+} createdb_failure_params;
+
/* non-export function prototypes */
+static void createdb_failure_callback(int code, Datum arg);
static bool get_db_info(const char *name, LOCKMODE lockmode,
Oid *dbIdP, Oid *ownerIdP,
int *encodingP, bool *dbIsTemplateP, bool *dbAllowConnP,
@@ -99,6 +107,7 @@ createdb(const CreatedbStmt *stmt)
int encoding = -1;
int dbconnlimit = -1;
int ctype_encoding;
+ createdb_failure_params fparms;
/* Extract options from the statement node tree */
foreach(option, stmt->options)
@@ -449,12 +458,15 @@ createdb(const CreatedbStmt *stmt)
/*
* Once we start copying subdirectories, we need to be able to clean 'em
- * up if we fail. Establish a TRY block to make sure this happens. (This
+ * up if we fail. Use an ENSURE block to make sure this happens. (This
* is not a 100% solution, because of the possibility of failure during
* transaction commit after we leave this routine, but it should handle
* most scenarios.)
*/
- PG_TRY();
+ fparms.src_dboid = src_dboid;
+ fparms.dest_dboid = dboid;
+ PG_ENSURE_ERROR_CLEANUP(createdb_failure_callback,
+ PointerGetDatum(&fparms));
{
/*
* Iterate through all tablespaces of the template database, and copy
@@ -565,18 +577,25 @@ createdb(const CreatedbStmt *stmt)
*/
database_file_update_needed();
}
- PG_CATCH();
- {
- /* Release lock on source database before doing recursive remove */
- UnlockSharedObject(DatabaseRelationId, src_dboid, 0,
- ShareLock);
+ PG_END_ENSURE_ERROR_CLEANUP(createdb_failure_callback,
+ PointerGetDatum(&fparms));
+}
+
+/* Error cleanup callback for createdb */
+static void
+createdb_failure_callback(int code, Datum arg)
+{
+ createdb_failure_params *fparms = (createdb_failure_params *) DatumGetPointer(arg);
- /* Throw away any successfully copied subdirectories */
- remove_dbtablespaces(dboid);
+ /*
+ * Release lock on source database before doing recursive remove.
+ * This is not essential but it seems desirable to release the lock
+ * as soon as possible.
+ */
+ UnlockSharedObject(DatabaseRelationId, fparms->src_dboid, 0, ShareLock);
- PG_RE_THROW();
- }
- PG_END_TRY();
+ /* Throw away any successfully copied subdirectories */
+ remove_dbtablespaces(fparms->dest_dboid);
}
diff --git a/src/backend/port/ipc_test.c b/src/backend/port/ipc_test.c
index c4a6f487db5cc2aa8a8780ea2fd9d6365cad3fd8..a9e133a2657948d42d643a9973010c3ff8feb8b6 100644
--- a/src/backend/port/ipc_test.c
+++ b/src/backend/port/ipc_test.c
@@ -21,7 +21,7 @@
*
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/port/ipc_test.c,v 1.24 2008/03/24 18:08:47 tgl Exp $
+ * $PostgreSQL: pgsql/src/backend/port/ipc_test.c,v 1.25 2008/04/16 23:59:40 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -58,7 +58,7 @@ char *DataDir = ".";
static struct ONEXIT
{
- void (*function) (int code, Datum arg);
+ pg_on_exit_callback function;
Datum arg;
} on_proc_exit_list[MAX_ON_EXITS], on_shmem_exit_list[MAX_ON_EXITS];
@@ -85,7 +85,7 @@ shmem_exit(int code)
}
void
- on_shmem_exit(void (*function) (int code, Datum arg), Datum arg)
+on_shmem_exit(pg_on_exit_callback function, Datum arg)
{
if (on_shmem_exit_index >= MAX_ON_EXITS)
elog(FATAL, "out of on_shmem_exit slots");
@@ -114,9 +114,9 @@ ProcessInterrupts(void)
}
int
-ExceptionalCondition(char *conditionName,
- char *errorType,
- char *fileName,
+ExceptionalCondition(const char *conditionName,
+ const char *errorType,
+ const char *fileName,
int lineNumber)
{
fprintf(stderr, "TRAP: %s(\"%s\", File: \"%s\", Line: %d)\n",
diff --git a/src/backend/storage/ipc/ipc.c b/src/backend/storage/ipc/ipc.c
index 91fbea2ea4fbfce376834c66b051fa1d076f8c2c..ccfa8a27bf2e2900398aef8a4d7bda70d9786bf9 100644
--- a/src/backend/storage/ipc/ipc.c
+++ b/src/backend/storage/ipc/ipc.c
@@ -13,7 +13,7 @@
*
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/storage/ipc/ipc.c,v 1.100 2008/01/01 19:45:51 momjian Exp $
+ * $PostgreSQL: pgsql/src/backend/storage/ipc/ipc.c,v 1.101 2008/04/16 23:59:40 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -56,7 +56,7 @@ bool proc_exit_inprogress = false;
static struct ONEXIT
{
- void (*function) (int code, Datum arg);
+ pg_on_exit_callback function;
Datum arg;
} on_proc_exit_list[MAX_ON_EXITS], on_shmem_exit_list[MAX_ON_EXITS];
@@ -184,7 +184,7 @@ shmem_exit(int code)
* ----------------------------------------------------------------
*/
void
- on_proc_exit(void (*function) (int code, Datum arg), Datum arg)
+on_proc_exit(pg_on_exit_callback function, Datum arg)
{
if (on_proc_exit_index >= MAX_ON_EXITS)
ereport(FATAL,
@@ -205,7 +205,7 @@ void
* ----------------------------------------------------------------
*/
void
- on_shmem_exit(void (*function) (int code, Datum arg), Datum arg)
+on_shmem_exit(pg_on_exit_callback function, Datum arg)
{
if (on_shmem_exit_index >= MAX_ON_EXITS)
ereport(FATAL,
@@ -218,6 +218,24 @@ void
++on_shmem_exit_index;
}
+/* ----------------------------------------------------------------
+ * cancel_shmem_exit
+ *
+ * this function removes an entry, if present, from the list of
+ * functions to be invoked by shmem_exit(). For simplicity,
+ * only the latest entry can be removed. (We could work harder
+ * but there is no need for current uses.)
+ * ----------------------------------------------------------------
+ */
+void
+cancel_shmem_exit(pg_on_exit_callback function, Datum arg)
+{
+ if (on_shmem_exit_index > 0 &&
+ on_shmem_exit_list[on_shmem_exit_index - 1].function == function &&
+ on_shmem_exit_list[on_shmem_exit_index - 1].arg == arg)
+ --on_shmem_exit_index;
+}
+
/* ----------------------------------------------------------------
* on_exit_reset
*
diff --git a/src/include/access/nbtree.h b/src/include/access/nbtree.h
index 1422994506d539c685ab2f907cd6944cecf8fe08..ec3ac5fbf7acc7f503cce415d3e66cacc42184d9 100644
--- a/src/include/access/nbtree.h
+++ b/src/include/access/nbtree.h
@@ -7,7 +7,7 @@
* Portions Copyright (c) 1996-2008, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
- * $PostgreSQL: pgsql/src/include/access/nbtree.h,v 1.117 2008/04/10 22:25:25 tgl Exp $
+ * $PostgreSQL: pgsql/src/include/access/nbtree.h,v 1.118 2008/04/16 23:59:40 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -574,6 +574,7 @@ extern void _bt_killitems(IndexScanDesc scan, bool haveLock);
extern BTCycleId _bt_vacuum_cycleid(Relation rel);
extern BTCycleId _bt_start_vacuum(Relation rel);
extern void _bt_end_vacuum(Relation rel);
+extern void _bt_end_vacuum_callback(int code, Datum arg);
extern Size BTreeShmemSize(void);
extern void BTreeShmemInit(void);
diff --git a/src/include/storage/ipc.h b/src/include/storage/ipc.h
index eb89f9a7daebac1383dacc2e5d40d78c67e557e4..2123852bb73e7b857270702659d8f42134f8400c 100644
--- a/src/include/storage/ipc.h
+++ b/src/include/storage/ipc.h
@@ -11,21 +11,63 @@
* Portions Copyright (c) 1996-2008, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
- * $PostgreSQL: pgsql/src/include/storage/ipc.h,v 1.74 2008/01/01 19:45:59 momjian Exp $
+ * $PostgreSQL: pgsql/src/include/storage/ipc.h,v 1.75 2008/04/16 23:59:40 tgl Exp $
*
*-------------------------------------------------------------------------
*/
#ifndef IPC_H
#define IPC_H
+typedef void (*pg_on_exit_callback) (int code, Datum arg);
+
+/*----------
+ * API for handling cleanup that must occur during either ereport(ERROR)
+ * or ereport(FATAL) exits from a block of code. (Typical examples are
+ * undoing transient changes to shared-memory state.)
+ *
+ * PG_ENSURE_ERROR_CLEANUP(cleanup_function, arg);
+ * {
+ * ... code that might throw ereport(ERROR) or ereport(FATAL) ...
+ * }
+ * PG_END_ENSURE_ERROR_CLEANUP(cleanup_function, arg);
+ *
+ * where the cleanup code is in a function declared per pg_on_exit_callback.
+ * The Datum value "arg" can carry any information the cleanup function
+ * needs.
+ *
+ * This construct ensures that cleanup_function() will be called during
+ * either ERROR or FATAL exits. It will not be called on successful
+ * exit from the controlled code. (If you want it to happen then too,
+ * call the function yourself from just after the construct.)
+ *
+ * Note: the macro arguments are multiply evaluated, so avoid side-effects.
+ *----------
+ */
+#define PG_ENSURE_ERROR_CLEANUP(cleanup_function, arg) \
+ do { \
+ on_shmem_exit(cleanup_function, arg); \
+ PG_TRY()
+
+#define PG_END_ENSURE_ERROR_CLEANUP(cleanup_function, arg) \
+ cancel_shmem_exit(cleanup_function, arg); \
+ PG_CATCH(); \
+ { \
+ cancel_shmem_exit(cleanup_function, arg); \
+ cleanup_function (0, arg); \
+ PG_RE_THROW(); \
+ } \
+ PG_END_TRY(); \
+ } while (0)
+
/* ipc.c */
extern bool proc_exit_inprogress;
extern void proc_exit(int code);
extern void shmem_exit(int code);
-extern void on_proc_exit(void (*function) (int code, Datum arg), Datum arg);
-extern void on_shmem_exit(void (*function) (int code, Datum arg), Datum arg);
+extern void on_proc_exit(pg_on_exit_callback function, Datum arg);
+extern void on_shmem_exit(pg_on_exit_callback function, Datum arg);
+extern void cancel_shmem_exit(pg_on_exit_callback function, Datum arg);
extern void on_exit_reset(void);
/* ipci.c */
diff --git a/src/include/utils/elog.h b/src/include/utils/elog.h
index 3b980cae79a462f1d7b0d3419fa2738c4c6a3833..b7777e8f5f95f470c1ba259fb4f1bdf81b4db34d 100644
--- a/src/include/utils/elog.h
+++ b/src/include/utils/elog.h
@@ -7,7 +7,7 @@
* Portions Copyright (c) 1996-2008, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
- * $PostgreSQL: pgsql/src/include/utils/elog.h,v 1.92 2008/03/24 18:08:47 tgl Exp $
+ * $PostgreSQL: pgsql/src/include/utils/elog.h,v 1.93 2008/04/16 23:59:40 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -204,6 +204,13 @@ extern PGDLLIMPORT ErrorContextCallback *error_context_stack;
* of levels this will work for. It's best to keep the error recovery
* section simple enough that it can't generate any new errors, at least
* not before popping the error stack.
+ *
+ * Note: an ereport(FATAL) will not be caught by this construct; control will
+ * exit straight through proc_exit(). Therefore, do NOT put any cleanup
+ * of non-process-local resources into the error recovery section, at least
+ * not without taking thought for what will happen during ereport(FATAL).
+ * The PG_ENSURE_ERROR_CLEANUP macros provided by storage/ipc.h may be
+ * helpful in such cases.
*----------
*/
#define PG_TRY() \