Separate verbs of sqlite3_config() and sqlite3_db_config() into their
own namespaces. Allow SQLITE3_DBCONFIG_LOOKASIDE to specific an external
memory buffer. (CVS 5536)
FossilOrigin-Name: 5dd865da5e787c10ef4c9e96647724bfab9dea01
diff --git a/src/main.c b/src/main.c
index 8400dae..68500eb 100644
--- a/src/main.c
+++ b/src/main.c
@@ -14,7 +14,7 @@
** other files are for internal use by SQLite and should not be
** accessed by users of the library.
**
-** $Id: main.c,v 1.485 2008/08/01 18:47:02 drh Exp $
+** $Id: main.c,v 1.486 2008/08/04 20:13:27 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>
@@ -294,8 +294,14 @@
** Set up the lookaside buffers for a database connection.
** Return SQLITE_OK on success.
** If lookaside is already active, return SQLITE_BUSY.
+**
+** The sz parameter is the number of bytes in each lookaside slot.
+** The cnt parameter is the number of slots. If pStart is NULL the
+** space for the lookaside memory is obtained from sqlite3_malloc().
+** If pStart is not NULL then it is sz*cnt bytes of memory to use for
+** the lookaside memory.
*/
-static int setupLookaside(sqlite3 *db, int sz, int cnt){
+static int setupLookaside(sqlite3 *db, void *pBuf, int sz, int cnt){
void *pStart;
if( db->lookaside.nOut ){
return SQLITE_BUSY;
@@ -303,13 +309,20 @@
if( sz<0 ) sz = 0;
if( cnt<0 ) cnt = 0;
sz = (sz+7)&~7;
- sqlite3BeginBenignMalloc();
- pStart = sqlite3Malloc( sz*cnt );
- sqlite3EndBenignMalloc();
- sqlite3_free(db->lookaside.pStart);
+ if( pBuf==0 ){
+ sqlite3BeginBenignMalloc();
+ pStart = sqlite3Malloc( sz*cnt );
+ sqlite3EndBenignMalloc();
+ }else{
+ pStart = pBuf;
+ }
+ if( db->lookaside.bMalloced ){
+ sqlite3_free(db->lookaside.pStart);
+ }
db->lookaside.pStart = pStart;
db->lookaside.pFree = 0;
db->lookaside.sz = sz;
+ db->lookaside.bMalloced = pBuf==0;
if( pStart ){
int i;
LookasideSlot *p;
@@ -336,10 +349,11 @@
int rc;
va_start(ap, op);
switch( op ){
- case SQLITE_CONFIG_LOOKASIDE: {
+ case SQLITE_DBCONFIG_LOOKASIDE: {
+ void *pBuf = va_arg(ap, void*);
int sz = va_arg(ap, int);
int cnt = va_arg(ap, int);
- rc = setupLookaside(db, sz, cnt);
+ rc = setupLookaside(db, pBuf, sz, cnt);
break;
}
default: {
@@ -545,7 +559,9 @@
sqlite3_mutex_leave(db->mutex);
db->magic = SQLITE_MAGIC_CLOSED;
sqlite3_mutex_free(db->mutex);
- sqlite3_free(db->lookaside.pStart);
+ if( db->lookaside.bMalloced ){
+ sqlite3_free(db->lookaside.pStart);
+ }
sqlite3_free(db);
return SQLITE_OK;
}
@@ -1523,7 +1539,7 @@
#endif
/* Enable the lookaside-malloc subsystem */
- setupLookaside(db, sqlite3Config.szLookaside, sqlite3Config.nLookaside);
+ setupLookaside(db, 0, sqlite3Config.szLookaside, sqlite3Config.nLookaside);
opendb_out:
if( db ){
diff --git a/src/sqlite.h.in b/src/sqlite.h.in
index 0ee086b..5df36cc 100644
--- a/src/sqlite.h.in
+++ b/src/sqlite.h.in
@@ -30,7 +30,7 @@
** the version number) and changes its name to "sqlite3.h" as
** part of the build process.
**
-** @(#) $Id: sqlite.h.in,v 1.385 2008/08/04 13:44:57 drh Exp $
+** @(#) $Id: sqlite.h.in,v 1.386 2008/08/04 20:13:27 drh Exp $
*/
#ifndef _SQLITE3_H_
#define _SQLITE3_H_
@@ -983,8 +983,9 @@
** The second argument to sqlite3_db_config(D,V,...) is the
** configuration verb - an integer code that indicates what
** aspect of the [database connection] is being configured.
-** Choices for this value are [SQLITE_CONFIG_LOOKASIDE].
+** The only choice for this value is [SQLITE_DBCONFIG_LOOKASIDE].
** New verbs are likely to be added in future releases of SQLite.
+** Additional arguments depend on the verb.
*/
int sqlite3_db_config(sqlite3*, int op, ...);
@@ -1192,6 +1193,36 @@
#define SQLITE_CONFIG_CHUNKALLOC 12 /* int threshold */
#define SQLITE_CONFIG_LOOKASIDE 13 /* int int */
+/*
+** CAPI3REF: Configuration Options {H10170} <S20000>
+** EXPERIMENTAL
+**
+** These constants are the available integer configuration options that
+** can be passed as the second argument to the [sqlite3_db_config()] interface.
+**
+** New configuration options may be added in future releases of SQLite.
+** Existing configuration options might be discontinued. Applications
+** should check the return code from [sqlite3_db_config()] to make sure that
+** the call worked. The [sqlite3_db_config()] interface will return a
+** non-zero [error code] if a discontinued or unsupported configuration option
+** is invoked.
+**
+** <dl>
+** <dt>SQLITE_DBCONFIG_LOOKASIDE</dt>
+** <dd>This option takes three additional arguments that determine the
+** [lookaside memory allocator] configuration for the [database connection].
+** The first argument (the third parameter to [sqlite3_db_config()] is a
+** pointer to a memory buffer to use for lookaside memory. The first
+** argument may be NULL in which case SQLite will allocate the lookaside
+** buffer itself using [sqlite3_malloc()]. The second argument is the
+** size of each lookaside buffer slot and the third argument is the number of
+** slots. The size of the buffer in the first argument must be greater than
+** or equal to the product of the second and third arguments.</dd>
+**
+** </dl>
+*/
+#define SQLITE_DBCONFIG_LOOKASIDE 1001 /* void* int int */
+
/*
** CAPI3REF: Enable Or Disable Extended Result Codes {H12200} <S10700>
diff --git a/src/sqliteInt.h b/src/sqliteInt.h
index 6897671..68de4a1 100644
--- a/src/sqliteInt.h
+++ b/src/sqliteInt.h
@@ -11,7 +11,7 @@
*************************************************************************
** Internal interface definitions for SQLite.
**
-** @(#) $Id: sqliteInt.h,v 1.751 2008/08/02 15:32:40 danielk1977 Exp $
+** @(#) $Id: sqliteInt.h,v 1.752 2008/08/04 20:13:27 drh Exp $
*/
#ifndef _SQLITEINT_H_
#define _SQLITEINT_H_
@@ -575,6 +575,7 @@
struct Lookaside {
u16 sz; /* Size of each buffer in bytes */
u8 bEnabled; /* True if use lookaside. False to ignore it */
+ u8 bMalloced; /* True if pStart obtained from sqlite3_malloc() */
int nOut; /* Number of buffers currently checked out */
int mxOut; /* Highwater mark for nOut */
LookasideSlot *pFree; /* List if available buffers */
diff --git a/src/test_malloc.c b/src/test_malloc.c
index 8eb73d8..449cdb2 100644
--- a/src/test_malloc.c
+++ b/src/test_malloc.c
@@ -13,7 +13,7 @@
** This file contains code used to implement test interfaces to the
** memory allocation subsystem.
**
-** $Id: test_malloc.c,v 1.45 2008/08/01 16:31:14 drh Exp $
+** $Id: test_malloc.c,v 1.46 2008/08/04 20:13:27 drh Exp $
*/
#include "sqliteInt.h"
#include "tcl.h"
@@ -1005,8 +1005,11 @@
/*
-** Usage: sqlite3_db_config_lookaside CONNECTION SIZE COUNT
+** Usage: sqlite3_db_config_lookaside CONNECTION BUFID SIZE COUNT
**
+** There are two static buffers with BUFID 1 and 2. Each static buffer
+** is 10KB in size. A BUFID of 0 indicates that the buffer should be NULL
+** which will cause sqlite3_db_config() to allocate space on its own.
*/
static int test_db_config_lookaside(
void * clientData,
@@ -1017,15 +1020,25 @@
int rc;
int sz, cnt;
sqlite3 *db;
+ int bufid;
+ static char azBuf[2][10000];
int getDbPointer(Tcl_Interp*, const char*, sqlite3**);
- if( objc!=4 ){
- Tcl_WrongNumArgs(interp, 1, objv, "SIZE COUNT");
+ if( objc!=5 ){
+ Tcl_WrongNumArgs(interp, 1, objv, "BUFID SIZE COUNT");
return TCL_ERROR;
}
if( getDbPointer(interp, Tcl_GetString(objv[1]), &db) ) return TCL_ERROR;
- if( Tcl_GetIntFromObj(interp, objv[2], &sz) ) return TCL_ERROR;
- if( Tcl_GetIntFromObj(interp, objv[3], &cnt) ) return TCL_ERROR;
- rc = sqlite3_db_config(db, SQLITE_CONFIG_LOOKASIDE, sz, cnt);
+ if( Tcl_GetIntFromObj(interp, objv[2], &bufid) ) return TCL_ERROR;
+ if( Tcl_GetIntFromObj(interp, objv[3], &sz) ) return TCL_ERROR;
+ if( Tcl_GetIntFromObj(interp, objv[4], &cnt) ) return TCL_ERROR;
+ if( bufid==0 ){
+ rc = sqlite3_db_config(db, SQLITE_DBCONFIG_LOOKASIDE, 0, sz, cnt);
+ }else if( bufid>=1 && bufid<=2 && sz*cnt<=sizeof(azBuf[0]) ){
+ rc = sqlite3_db_config(db, SQLITE_DBCONFIG_LOOKASIDE, azBuf[bufid], sz,cnt);
+ }else{
+ Tcl_AppendResult(interp, "illegal arguments - see documentation", (char*)0);
+ return TCL_ERROR;
+ }
Tcl_SetObjResult(interp, Tcl_NewIntObj(rc));
return TCL_OK;
}