Preliminary backend overlay support, based on backglue, not tested...

servers/slapd/Makefile.in

@@ -23,7 +23,7 @@ SRCS	= main.c globals.c config.c daemon.c \
 		oidm.c starttls.c index.c sets.c referral.c root_dse.c \
 		sasl.c module.c mra.c mods.c sl_malloc.c limits.c \
 		backglue.c operational.c matchedValues.c cancel.c syncrepl.c \
-		$(@PLAT@_SRCS)
+		backover.c $(@PLAT@_SRCS)
 
 OBJS	= main.o globals.o config.o daemon.o \
 		connection.o search.o filter.o add.o cr.o \
@@ -37,7 +37,7 @@ OBJS	= main.o globals.o config.o daemon.o \
 		oidm.o starttls.o index.o sets.o referral.o root_dse.o \
 		sasl.o module.o mra.o mods.o sl_malloc.o limits.o \
 		backglue.o operational.o matchedValues.o cancel.o syncrepl.o \
-		$(@PLAT@_OBJS)
+		backover.o $(@PLAT@_OBJS)
 
 LDAP_INCDIR= ../../include -I$(srcdir)/slapi
 LDAP_LIBDIR= ../../libraries

servers/slapd/backover.c

@@ -0,0 +1,317 @@
+/* backover.c - backend overlay routines */
+/* $OpenLDAP$ */
+/*
+ * Copyright 2003 The OpenLDAP Foundation, All Rights Reserved.
+ * COPYING RESTRICTIONS APPLY, see COPYRIGHT file
+ */
+
+/*
+ * Functions to overlay other modules over a backend.
+ *
+ *  -- Howard Chu
+ */
+
+#include "portable.h"
+
+#include <stdio.h>
+
+#include <ac/string.h>
+#include <ac/socket.h>
+
+#define SLAPD_TOOLS
+#include "slap.h"
+
+static slap_overinst *overlays;
+
+enum db_which { db_open = 0, db_close, db_destroy };
+
+static int
+over_db_func(
+	BackendDB *be,
+	enum db_which which
+)
+{
+	slap_overinfo *oi = (slap_overinfo *) be->bd_info;
+	slap_overinst *on = oi->oi_list;
+	BackendDB bd;
+	BI_db_open **func;
+	int rc = 0;
+
+	func = &oi->oi_bi.bi_db_open;
+	if ( func[which] ) {
+		rc = func[which]( &oi->oi_bd );
+		if ( rc ) return rc;
+	}
+
+	bd = *be;
+	for (; on; on=on->on_next) {
+		bd.bd_info = &on->on_bi;
+		func = &on->on_bi.bi_db_open;
+		if (func[which]) {
+			rc = func[which]( &bd );
+			if ( rc ) break;
+		}
+	}
+	return rc;
+}
+
+static int
+over_db_config(
+	BackendDB *be,
+	const char *fname,
+	int lineno,
+	int argc,
+	char **argv
+)
+{
+	slap_overinfo *oi = (slap_overinfo *) be->bd_info;
+	slap_overinst *on = oi->oi_list;
+	BackendDB bd;
+	int rc = 0;
+
+	if ( oi->oi_bi.bi_db_config ) {
+		rc = oi->oi_bi.bi_db_config( &oi->oi_bd, fname, lineno,
+			argc, argv );
+		if ( rc ) return rc;
+	}
+
+	bd = *be;
+	for (; on; on=on->on_next) {
+		bd.bd_info = &on->on_bi;
+		if (on->on_bi.bi_db_config) {
+			rc = on->on_bi.bi_db_config( &bd, fname, lineno,
+				argc, argv );
+			if ( rc ) break;
+		}
+	}
+	return rc;
+}
+
+static int
+over_db_open(
+	BackendDB *be
+)
+{
+	return over_db_func( be, db_open );
+}
+
+static int
+over_db_close(
+	BackendDB *be
+)
+{
+	return over_db_func( be, db_close );
+}
+
+static int
+over_db_destroy(
+	BackendDB *be
+)
+{
+	slap_overinfo *oi = (slap_overinfo *) be->bd_info;
+	slap_overinst *on = oi->oi_list, *next;
+	int rc;
+
+	rc = over_db_func( be, db_destroy );
+
+	for (next = on->on_next; on; on=next) {
+		next = on->on_next;
+		free( on );
+	}
+	free( oi );
+	return rc;
+}
+
+static int
+over_back_response ( Operation *op, SlapReply *rs )
+{
+	slap_overinfo *oi = (slap_overinfo *) op->o_bd->bd_info;
+	slap_overinst *on = oi->oi_list;
+	int rc = 0;
+	BackendDB *be = op->o_bd, db = *op->o_bd;
+
+	op->o_bd = &db;
+	for (; on; on=on->on_next ) {
+		if ( on->on_response ) {
+			db.bd_info = (BackendInfo *)on;
+			rc = on->on_response( op, rs );
+			if ( rc ) break;
+		}
+	}
+	op->o_bd = be;
+	return rc;
+}
+
+enum op_which { op_bind = 0, op_unbind, op_search, op_compare,
+	op_modify, op_modrdn, op_add, op_delete, op_abandon,
+	op_cancel, op_extended };
+
+static int
+over_op_func(
+	Operation *op,
+	SlapReply *rs,
+	enum op_which which
+)
+{
+	slap_overinfo *oi = (slap_overinfo *) op->o_bd->bd_info;
+	slap_overinst *on = oi->oi_list;
+	int rc = 0;
+	BackendDB *be = op->o_bd, db = *op->o_bd;
+	BI_op_bind **func;
+	slap_callback cb = {over_back_response, NULL};
+
+	op->o_bd = &db;
+	for (; on; on=on->on_next ) {
+		func = &on->on_bi.bi_op_bind;
+		if ( func[which] ) {
+			db.bd_info = (BackendInfo *)on;
+			rc = func[which]( op, rs );
+			if ( rc ) break;
+		}
+	}
+	func = &oi->oi_bi.bi_op_bind;
+	if ( func[which] ) {
+		rc = func[which]( op, rs );
+	}
+
+	op->o_bd = be;
+	return rc;
+}
+
+static int
+over_op_bind( Operation *op, SlapReply *rs )
+{
+	return over_op_func( op, rs, op_bind );
+}
+
+static int
+over_op_unbind( Operation *op, SlapReply *rs )
+{
+	return over_op_func( op, rs, op_unbind );
+}
+
+static int
+over_op_search( Operation *op, SlapReply *rs )
+{
+	return over_op_func( op, rs, op_search );
+}
+
+static int
+over_op_compare( Operation *op, SlapReply *rs )
+{
+	return over_op_func( op, rs, op_compare );
+}
+
+static int
+over_op_modify( Operation *op, SlapReply *rs )
+{
+	return over_op_func( op, rs, op_modify );
+}
+
+static int
+over_op_modrdn( Operation *op, SlapReply *rs )
+{
+	return over_op_func( op, rs, op_modrdn );
+}
+
+static int
+over_op_add( Operation *op, SlapReply *rs )
+{
+	return over_op_func( op, rs, op_add );
+}
+
+static int
+over_op_delete( Operation *op, SlapReply *rs )
+{
+	return over_op_func( op, rs, op_delete );
+}
+
+static int
+over_op_abandon( Operation *op, SlapReply *rs )
+{
+	return over_op_func( op, rs, op_abandon );
+}
+
+static int
+over_op_cancel( Operation *op, SlapReply *rs )
+{
+	return over_op_func( op, rs, op_cancel );
+}
+
+static int
+over_op_extended( Operation *op, SlapReply *rs )
+{
+	return over_op_func( op, rs, op_extended );
+}
+
+int
+overlay_register(
+	slap_overinst *on
+)
+{
+	on->on_next = overlays;
+	overlays = on;
+	return 0;
+}
+
+static const char overtype[] = "over";
+
+/* add an overlay to a particular backend. */
+int
+overlay_config( BackendDB *be, const char *ov )
+{
+	slap_overinst *on, *on2, *prev;
+	slap_overinfo *oi;
+	BackendInfo *bi;
+
+	for ( on = overlays; on; on=on->on_next ) {
+		if (!strcmp( ov, on->on_bi.bi_type ) )
+			break;
+	}
+	if (!on) {
+		Debug( LDAP_DEBUG_ANY, "overlay %s not found\n", ov, 0, 0 );
+		return 1;
+	}
+
+	if ( be->bd_info->bi_type != overtype ) {
+		oi = ch_malloc( sizeof(slap_overinfo) );
+		oi->oi_bd = *be;
+		oi->oi_bi = *be->bd_info;
+		oi->oi_list = NULL;
+		bi = (BackendInfo *)oi;
+
+		bi->bi_type = (char *)overtype;
+
+		bi->bi_db_config = over_db_config;
+		bi->bi_db_open = over_db_open;
+		bi->bi_db_close = over_db_close;
+		bi->bi_db_destroy = over_db_destroy;
+
+		bi->bi_op_bind = over_op_bind;
+		bi->bi_op_unbind = over_op_unbind;
+		bi->bi_op_search = over_op_search;
+		bi->bi_op_compare = over_op_compare;
+		bi->bi_op_modify = over_op_modify;
+		bi->bi_op_modrdn = over_op_modrdn;
+		bi->bi_op_add = over_op_add;
+		bi->bi_op_delete = over_op_delete;
+		bi->bi_op_abandon = over_op_abandon;
+		bi->bi_op_cancel = over_op_cancel;
+		bi->bi_extended = over_op_extended;
+
+		be->bd_info = bi;
+	}
+
+	oi = (slap_overinfo *) be->bd_info;
+	for ( prev=NULL, on2 = oi->oi_list; on2; prev=on2, on2=on2->on_next );
+	on2 = ch_malloc( sizeof(slap_overinst) );
+	if ( !prev ) {
+		oi->oi_list = on2;
+	} else {
+		prev->on_next = on2;
+	}
+	*on2 = *on;
+
+	return 0;
+}
+

servers/slapd/config.c

@@ -910,7 +910,7 @@ read_config( const char *fname, int depth )
 					"subordinate keyword must appear inside a database "
 					"definition.\n", fname, lineno, 0 );
 #else
-				Debug( LDAP_DEBUG_ANY, "%s: line %d: suffix line "
+				Debug( LDAP_DEBUG_ANY, "%s: line %d: subordinate keyword "
 					"must appear inside a database definition.\n",
 				    fname, lineno, 0 );
 #endif
@@ -921,6 +921,24 @@ read_config( const char *fname, int depth )
 				num_subordinates++;
 			}
 
+		/* add an overlay to this backend */
+		} else if ( strcasecmp( cargv[0], "overlay" ) == 0 ) {
+			if ( be == NULL ) {
+#ifdef NEW_LOGGING
+				LDAP_LOG( CONFIG, INFO, "%s: line %d: "
+					"overlay keyword must appear inside a database "
+					"definition.\n", fname, lineno, 0 );
+#else
+				Debug( LDAP_DEBUG_ANY, "%s: line %d: overlay keyword "
+					"must appear inside a database definition.\n",
+				    fname, lineno, 0 );
+#endif
+				return 1;
+
+			} else {
+				return overlay_config( be, cargv[1] );
+			}
+
 		/* set database suffix */
 		} else if ( strcasecmp( cargv[0], "suffix" ) == 0 ) {
 			Backend *tmp_be;

servers/slapd/proto-slap.h

@@ -253,6 +253,13 @@ LDAP_SLAPD_F (Attribute *) backend_operational(
 LDAP_SLAPD_F (int) glue_back_initialize( BackendInfo *bi );
 LDAP_SLAPD_F (int) glue_sub_init( void );
 
+/*
+ * backover.c
+ */
+
+LDAP_SLAPD_F (int) overlay_register( slap_overinst *on );
+LDAP_SLAPD_F (int) overlay_config( BackendDB *be, const char *ov );
+
 /*
  * ch_malloc.c
  */

servers/slapd/slap.h

@@ -1763,6 +1763,22 @@ typedef struct slap_callback {
 	void *sc_private;
 } slap_callback;
 
+struct slap_overinfo;
+
+typedef struct slap_overinst {
+	BackendInfo on_bi;
+	slap_response *on_response;
+	void *on_private;
+	struct slap_overinfo *on_info;
+	struct slap_overinst *on_next;
+} slap_overinst;
+
+typedef struct slap_overinfo {
+	BackendInfo oi_bi;
+	BackendDB oi_bd;
+	slap_overinst *oi_list;
+} slap_overinfo;
+
 /*
  * Paged Results state
  */

servers/slapd/tools/Makefile.in

@@ -46,7 +46,7 @@ SLAPD_OBJS = ../globals.o ../config.o ../ch_malloc.o ../cr.o ../backend.o \
 		../init.o ../controls.o ../kerberos.o ../passwd.o \
 		../index.o ../extended.o ../starttls.o ../sets.o ../mra.o \
 		../referral.o ../backglue.o ../oidm.o ../mods.o ../operation.o \
-		../cancel.o ../sl_malloc.o
+		../cancel.o ../sl_malloc.o ../backover.o
 
 SLAPOBJS = $(SLAPD_OBJS) slapcommon.o mimic.o