Use a single malloc for entry_decode instead of two - partially decode

the entry to get nvals first, so the size can be computed.

servers/slapd/back-bdb/id2entry.c

@@ -18,6 +18,7 @@
 
 #include <stdio.h>
 #include <ac/string.h>
+#include <ac/errno.h>
 
 #include "back-bdb.h"
 
@@ -100,8 +101,9 @@ int bdb_id2entry(
 	DB *db = bdb->bi_id2entry->bdi_db;
 	DBT key, data;
 	DBC *cursor;
-	struct berval bv;
+	EntryHeader eh;
-	int rc = 0;
+	char buf[16];
+	int rc = 0, off;
 	ID nid;
 
 	*e = NULL;
@@ -112,7 +114,7 @@ int bdb_id2entry(
 	BDB_ID2DISK( id, &nid );
 
 	DBTzero( &data );
-	data.flags = DB_DBT_MALLOC;
+	data.flags = DB_DBT_USERMEM | DB_DBT_PARTIAL;
 
 	/* fetch it */
 	rc = db->cursor( db, tid, &cursor, bdb->bi_db_opflags );
@@ -122,19 +124,47 @@ int bdb_id2entry(
 	if ( !tid && locker )
 		cursor->locker = locker;
 
+	/* Get the nattrs / nvals counts first */
+	data.ulen = data.dlen = sizeof(buf);
+	data.data = buf;
 	rc = cursor->c_get( cursor, &key, &data, DB_SET );
+	if ( rc ) goto leave;
+
+	eh.bv.bv_val = buf;
+	eh.bv.bv_len = data.size;
+	rc = entry_header( &eh );
+	if ( rc ) goto leave;
+
+	/* Get the size */
+	data.flags ^= DB_DBT_PARTIAL;
+	data.ulen = 0;
+	rc = cursor->c_get( cursor, &key, &data, DB_CURRENT );
+	if ( rc != ENOMEM ) goto leave;
+
+	/* Allocate a block and retrieve the data */
+	off = eh.data - eh.bv.bv_val;
+	eh.bv.bv_len = eh.nvals * sizeof( struct berval ) + data.size;
+	eh.bv.bv_val = ch_malloc( eh.bv.bv_len );
+	eh.data = eh.bv.bv_val + eh.nvals * sizeof( struct berval );
+	data.data = eh.data;
+	data.ulen = data.size;
+
+	/* skip past already parsed nattr/nvals */
+	eh.data += off;
+
+	rc = cursor->c_get( cursor, &key, &data, DB_CURRENT );
+
+leave:
 	cursor->c_close( cursor );
 
 	if( rc != 0 ) {
 		return rc;
 	}
 
-	DBT2bv( &data, &bv );
-
 #ifdef SLAP_ZONE_ALLOC
-	rc = entry_decode(&bv, e, bdb->bi_cache.c_zctx);
+	rc = entry_decode(&eh, e, bdb->bi_cache.c_zctx);
 #else
-	rc = entry_decode(&bv, e);
+	rc = entry_decode(&eh, e);
 #endif
 
 	if( rc == 0 ) {
@@ -144,11 +174,11 @@ int bdb_id2entry(
 		 * decoded in place.
 		 */
 #ifndef SLAP_ZONE_ALLOC
-		ch_free(data.data);
+		ch_free(eh.bv.bv_val);
 #endif
 	}
 #ifdef SLAP_ZONE_ALLOC
-	ch_free(data.data);
+	ch_free(eh.bv.bv_val);
 #endif
 
 	return rc;

servers/slapd/back-bdb/tools.c

@@ -18,6 +18,7 @@
 
 #include <stdio.h>
 #include <ac/string.h>
+#include <ac/errno.h>
 
 #define AVL_INTERNAL
 #include "back-bdb.h"
@@ -25,6 +26,8 @@
 
 static DBC *cursor = NULL;
 static DBT key, data;
+static EntryHeader eh;
+static int eoff;
 
 typedef struct dn_id {
 	ID id;
@@ -82,7 +85,7 @@ int bdb_tool_entry_open(
 	DBTzero( &key );
 	DBTzero( &data );
 	key.flags = DB_DBT_REALLOC;
-	data.flags = DB_DBT_REALLOC;
+	data.flags = DB_DBT_USERMEM;
 
 	if (cursor == NULL) {
 		int rc = bdb->bi_id2entry->bdi_db->cursor(
@@ -132,9 +135,9 @@ int bdb_tool_entry_close(
 		ch_free( key.data );
 		key.data = NULL;
 	}
-	if( data.data ) {
+	if( eh.bv.bv_val ) {
-		ch_free( data.data );
+		ch_free( eh.bv.bv_val );
-		data.data = NULL;
+		eh.bv.bv_val = NULL;
 	}
 
 	if( cursor ) {
@@ -165,14 +168,19 @@ ID bdb_tool_entry_next(
 	int rc;
 	ID id;
 	struct bdb_info *bdb = (struct bdb_info *) be->be_private;
+	char buf[16], *dptr;
 
 	assert( be != NULL );
 	assert( slapMode & SLAP_TOOL_MODE );
 	assert( bdb != NULL );
 	
+	/* Get the header */
+	data.ulen = data.dlen = sizeof( buf );
+	data.data = buf;
+	data.flags |= DB_DBT_PARTIAL;
 	rc = cursor->c_get( cursor, &key, &data, DB_NEXT );
 
-	if( rc != 0 ) {
+	if( rc ) {
 		/* If we're doing linear indexing and there are more attrs to
 		 * index, and we're at the end of the database, start over.
 		 */
@@ -190,7 +198,13 @@ ID bdb_tool_entry_next(
 		}
 	}
 
-	if( data.data == NULL ) {
+	dptr = eh.bv.bv_val;
+	eh.bv.bv_val = buf;
+	eh.bv.bv_len = data.size;
+	rc = entry_header( &eh );
+	eoff = eh.data - eh.bv.bv_val;
+	eh.bv.bv_val = dptr;
+	if( rc ) {
 		return NOID;
 	}
 
@@ -248,48 +262,64 @@ int bdb_tool_id2entry_get(
 
 Entry* bdb_tool_entry_get( BackendDB *be, ID id )
 {
-	int rc;
+	int rc, off;
 	Entry *e = NULL;
-	struct berval bv;
+	char *dptr;
 
 	assert( be != NULL );
 	assert( slapMode & SLAP_TOOL_MODE );
-	assert( data.data != NULL );
 
-	DBT2bv( &data, &bv );
+	/* Get the size */
+	data.flags ^= DB_DBT_PARTIAL;
+	data.ulen = 0;
+    rc = cursor->c_get( cursor, &key, &data, DB_CURRENT );
+	if ( rc != ENOMEM ) goto leave;
+
+	/* Allocate a block and retrieve the data */
+	eh.bv.bv_len = eh.nvals * sizeof( struct berval ) + data.size;
+	eh.bv.bv_val = ch_realloc( eh.bv.bv_val, eh.bv.bv_len );
+	eh.data = eh.bv.bv_val + eh.nvals * sizeof( struct berval );
+	data.data = eh.data;
+	data.ulen = data.size;
+
+	/* Skip past already parsed nattr/nvals */
+	eh.data += eoff;
+
+    rc = cursor->c_get( cursor, &key, &data, DB_CURRENT );
 
 #ifdef SLAP_ZONE_ALLOC
 	/* FIXME: will add ctx later */
-	rc = entry_decode( &bv, &e, NULL );
+	rc = entry_decode( &eh, &e, NULL );
 #else
-	rc = entry_decode( &bv, &e );
+	rc = entry_decode( &eh, &e );
 #endif
 
 	if( rc == LDAP_SUCCESS ) {
 		e->e_id = id;
-	}
 #ifdef BDB_HIER
-	if ( slapMode & SLAP_TOOL_READONLY ) {
+		if ( slapMode & SLAP_TOOL_READONLY ) {
-		EntryInfo *ei = NULL;
+			EntryInfo *ei = NULL;
-		Operation op = {0};
+			Operation op = {0};
-		Opheader ohdr = {0};
+			Opheader ohdr = {0};
 
-		op.o_hdr = &ohdr;
+			op.o_hdr = &ohdr;
-		op.o_bd = be;
+			op.o_bd = be;
-		op.o_tmpmemctx = NULL;
+			op.o_tmpmemctx = NULL;
-		op.o_tmpmfuncs = &ch_mfuncs;
+			op.o_tmpmfuncs = &ch_mfuncs;
 
-		rc = bdb_cache_find_parent( &op, NULL, cursor->locker, id, &ei );
+			rc = bdb_cache_find_parent( &op, NULL, cursor->locker, id, &ei );
-		if ( rc == LDAP_SUCCESS ) {
+			if ( rc == LDAP_SUCCESS ) {
-			bdb_cache_entryinfo_unlock( ei );
+				bdb_cache_entryinfo_unlock( ei );
-			e->e_private = ei;
+				e->e_private = ei;
-			ei->bei_e = e;
+				ei->bei_e = e;
-			bdb_fix_dn( e, 0 );
+				bdb_fix_dn( e, 0 );
-			ei->bei_e = NULL;
+				ei->bei_e = NULL;
-			e->e_private = NULL;
+				e->e_private = NULL;
+			}
 		}
-	}
 #endif
+	}
+leave:
 	return e;
 }
 

servers/slapd/entry.c

@@ -456,10 +456,6 @@ entry_clean( Entry *e )
 		free( e->e_bv.bv_val );
 	}
 
-	if ( &e->e_abv ) {
-		free( e->e_abv );
-	}
-
 	/* free attributes */
 	attrs_free( e->e_attrs );
 
@@ -720,20 +716,39 @@ int entry_encode(Entry *e, struct berval *bv)
 }
 
 /* Retrieve an Entry that was stored using entry_encode above.
- * We malloc a single block with the size stored above for the Entry
+ * First entry_header must be called to decode the size of the entry.
- * and all of its Attributes. We also must lookup the stored
+ * Then a single block of memory must be malloc'd to accomodate the
- * attribute names to get AttributeDescriptions. To detect if the
+ * bervals and the bulk data. Next the bulk data is retrieved from
- * attributes of an Entry are later modified, we note that e->e_attr
+ * the DB and parsed by entry_decode.
- * is always a constant offset from (e).
  *
  * Note: everything is stored in a single contiguous block, so
  * you can not free individual attributes or names from this
  * structure. Attempting to do so will likely corrupt memory.
  */
+int entry_header(EntryHeader *eh)
+{
+	unsigned char *ptr = (unsigned char *)eh->bv.bv_val;
+
+	eh->nattrs = entry_getlen(&ptr);
+	if ( !eh->nattrs ) {
+		Debug( LDAP_DEBUG_ANY,
+			"entry_header: attribute count was zero\n", 0, 0, 0);
+		return LDAP_OTHER;
+	}
+	eh->nvals = entry_getlen(&ptr);
+	if ( !eh->nvals ) {
+		Debug( LDAP_DEBUG_ANY,
+			"entry_header: value count was zero\n", 0, 0, 0);
+		return LDAP_OTHER;
+	}
+	eh->data = (char *)ptr;
+	return LDAP_SUCCESS;
+}
+
 #ifdef SLAP_ZONE_ALLOC
-int entry_decode(struct berval *bv, Entry **e, void *ctx)
+int entry_decode(EntryHeader *eh, Entry **e, void *ctx)
 #else
-int entry_decode(struct berval *bv, Entry **e)
+int entry_decode(EntryHeader *eh, Entry **e)
 #endif
 {
 	int i, j, count, nattrs, nvals;
@@ -742,24 +757,14 @@ int entry_decode(struct berval *bv, Entry **e)
 	Entry *x;
 	const char *text;
 	AttributeDescription *ad;
-	unsigned char *ptr = (unsigned char *)bv->bv_val;
+	unsigned char *ptr = (unsigned char *)eh->bv.bv_val;
 	BerVarray bptr;
 
-	nattrs = entry_getlen(&ptr);
+	nattrs = eh->nattrs;
-	if (!nattrs) {
+	nvals = eh->nvals;
-		Debug( LDAP_DEBUG_ANY,
-			"entry_decode: attribute count was zero\n", 0, 0, 0);
-		return LDAP_OTHER;
-	}
-	nvals = entry_getlen(&ptr);
-	if (!nvals) {
-		Debug( LDAP_DEBUG_ANY,
-			"entry_decode: value count was zero\n", 0, 0, 0);
-		return LDAP_OTHER;
-	}
 	x = entry_alloc();
 	x->e_attrs = attrs_alloc( nattrs );
-	x->e_abv = ch_malloc( nvals * sizeof( struct berval ));
+	ptr = (unsigned char *)eh->data;
 	i = entry_getlen(&ptr);
 	x->e_name.bv_val = (char *) ptr;
 	x->e_name.bv_len = i;
@@ -771,10 +776,10 @@ int entry_decode(struct berval *bv, Entry **e)
 	Debug( LDAP_DEBUG_TRACE,
 		"entry_decode: \"%s\"\n",
 		x->e_dn, 0, 0 );
-	x->e_bv = *bv;
+	x->e_bv = eh->bv;
 
 	a = x->e_attrs;
-	bptr = x->e_abv;
+	bptr = (BerVarray)eh->bv.bv_val;
 
 	while ((i = entry_getlen(&ptr))) {
 		struct berval bv;
@@ -853,9 +858,6 @@ Entry *entry_dup( Entry *e )
 	ber_dupbv( &ret->e_nname, &e->e_nname );
 	ret->e_attrs = attrs_dup( e->e_attrs );
 	ret->e_ocflags = e->e_ocflags;
-	ret->e_bv.bv_val = NULL;
-	ret->e_bv.bv_len = 0;
-	ret->e_private = NULL;
 
 	return ret;
 }

servers/slapd/proto-slap.h

@@ -853,12 +853,13 @@ LDAP_SLAPD_F (ber_len_t) entry_flatsize LDAP_P(( Entry *e, int norm ));
 LDAP_SLAPD_F (void) entry_partsize LDAP_P(( Entry *e, ber_len_t *len,
 	int *nattrs, int *nvals, int norm ));
 
+LDAP_SLAPD_F (int) entry_header LDAP_P(( EntryHeader *eh ));
 #ifdef SLAP_ZONE_ALLOC
 LDAP_SLAPD_F (int) entry_decode LDAP_P((
-						struct berval *bv, Entry **e, void *ctx ));
+						EntryHeader *eh, Entry **e, void *ctx ));
 #else
 LDAP_SLAPD_F (int) entry_decode LDAP_P((
-						struct berval *bv, Entry **e ));
+						EntryHeader *eh, Entry **e ));
 #endif
 LDAP_SLAPD_F (int) entry_encode LDAP_P(( Entry *e, struct berval *bv ));
 

servers/slapd/slap.h

@@ -1108,6 +1108,13 @@ typedef struct slap_attr {
 typedef unsigned long	ID;
 #define NOID	((ID)~0)
 
+typedef struct slap_entry_header {
+	struct berval bv;
+	char *data;
+	int nattrs;
+	int nvals;
+} EntryHeader;
+
 /*
  * represents an entry in core
  */
@@ -1131,7 +1138,6 @@ typedef struct slap_entry {
 	slap_mask_t	e_ocflags;
 
 	struct berval	e_bv;		/* For entry_encode/entry_decode */
-	struct berval	*e_abv;
 
 	/* for use by the backend for any purpose */
 	void*	e_private;