#include "sqliteInt.h"
#include "pager.h"
#include "btree.h"
#include "os.h"
#include <assert.h>
#define ROUND8(x) ((x+7)&~7)
#define MX_CELL_SIZE(pBt) (pBt->pageSize-8)
#define MX_CELL(pBt) ((pBt->pageSize-8)/3)
typedef struct MemPage MemPage;
typedef struct BtLock BtLock;
#ifndef SQLITE_FILE_HEADER
# define SQLITE_FILE_HEADER "SQLite format 3"
#endif
static const char zMagicHeader[] = SQLITE_FILE_HEADER;
#define PTF_INTKEY 0x01
#define PTF_ZERODATA 0x02
#define PTF_LEAFDATA 0x04
#define PTF_LEAF 0x08
struct MemPage {
u8 isInit;
u8 idxShift;
u8 nOverflow;
u8 intKey;
u8 leaf;
u8 zeroData;
u8 leafData;
u8 hasData;
u8 hdrOffset;
u8 childPtrSize;
u16 maxLocal;
u16 minLocal;
u16 cellOffset;
u16 idxParent;
u16 nFree;
u16 nCell;
struct _OvflCell {
u8 *pCell;
u16 idx;
} aOvfl[5];
BtShared *pBt;
u8 *aData;
DbPage *pDbPage;
Pgno pgno;
MemPage *pParent;
};
#define EXTRA_SIZE sizeof(MemPage)
struct Btree {
sqlite3 *pSqlite;
BtShared *pBt;
u8 inTrans;
};
#define TRANS_NONE 0
#define TRANS_READ 1
#define TRANS_WRITE 2
struct BtShared {
Pager *pPager;
BtCursor *pCursor;
MemPage *pPage1;
u8 inStmt;
u8 readOnly;
u8 maxEmbedFrac;
u8 minEmbedFrac;
u8 minLeafFrac;
u8 pageSizeFixed;
#ifndef SQLITE_OMIT_AUTOVACUUM
u8 autoVacuum;
#endif
u16 pageSize;
u16 usableSize;
int maxLocal;
int minLocal;
int maxLeaf;
int minLeaf;
BusyHandler *pBusyHandler;
u8 inTransaction;
int nRef;
int nTransaction;
void *pSchema;
void (*xFreeSchema)(void*);
#ifndef SQLITE_OMIT_SHARED_CACHE
BtLock *pLock;
BtShared *pNext;
#endif
};
typedef struct CellInfo CellInfo;
struct CellInfo {
u8 *pCell;
i64 nKey;
u32 nData;
u32 nPayload;
u16 nHeader;
u16 nLocal;
u16 iOverflow;
u16 nSize;
};
struct BtCursor {
Btree *pBtree;
BtCursor *pNext, *pPrev;
int (*xCompare)(void*,int,const void*,int,const void*);
void *pArg;
Pgno pgnoRoot;
MemPage *pPage;
int idx;
CellInfo info;
u8 wrFlag;
u8 eState;
void *pKey;
i64 nKey;
int skip;
};
#define CURSOR_INVALID 0
#define CURSOR_VALID 1
#define CURSOR_REQUIRESEEK 2
#if SQLITE_TEST
# define TRACE(X) if( sqlite3_btree_trace )\
\
{ printf X; fflush(stdout); }
int sqlite3_btree_trace=0;
#else
# define TRACE(X)
#endif
static int checkReadLocks(Btree*,Pgno,BtCursor*);
static u32 get2byte(unsigned char *p){
return (p[0]<<8) | p[1];
}
static u32 get4byte(unsigned char *p){
return (p[0]<<24) | (p[1]<<16) | (p[2]<<8) | p[3];
}
static void put2byte(unsigned char *p, u32 v){
p[0] = v>>8;
p[1] = v;
}
static void put4byte(unsigned char *p, u32 v){
p[0] = v>>24;
p[1] = v>>16;
p[2] = v>>8;
p[3] = v;
}
#define getVarint sqlite3GetVarint
#define getVarint32(A,B) ((*B=*(A))<=0x7f?1:sqlite3GetVarint32(A,B))
#define putVarint sqlite3PutVarint
#ifdef SQLITE_OMIT_DISKIO
# define PENDING_BYTE_PAGE(pBt) 0x7fffffff
#else
# define PENDING_BYTE_PAGE(pBt) ((PENDING_BYTE/(pBt)->pageSize)+1)
#endif
struct BtLock {
Btree *pBtree;
Pgno iTable;
u8 eLock;
BtLock *pNext;
};
#define READ_LOCK 1
#define WRITE_LOCK 2
#ifdef SQLITE_OMIT_SHARED_CACHE
#define queryTableLock(a,b,c) SQLITE_OK
#define lockTable(a,b,c) SQLITE_OK
#define unlockAllTables(a)
#else
static int queryTableLock(Btree *p, Pgno iTab, u8 eLock){
BtShared *pBt = p->pBt;
BtLock *pIter;
if( 0==sqlite3ThreadDataReadOnly()->useSharedData ){
return SQLITE_OK;
}
if(
!p->pSqlite ||
0==(p->pSqlite->flags&SQLITE_ReadUncommitted) ||
eLock==WRITE_LOCK ||
iTab==MASTER_ROOT
){
for(pIter=pBt->pLock; pIter; pIter=pIter->pNext){
if( pIter->pBtree!=p && pIter->iTable==iTab &&
(pIter->eLock!=eLock || eLock!=READ_LOCK) ){
return SQLITE_LOCKED;
}
}
}
return SQLITE_OK;
}
static int lockTable(Btree *p, Pgno iTable, u8 eLock){
BtShared *pBt = p->pBt;
BtLock *pLock = 0;
BtLock *pIter;
if( 0==sqlite3ThreadDataReadOnly()->useSharedData ){
return SQLITE_OK;
}
assert( SQLITE_OK==queryTableLock(p, iTable, eLock) );
if(
(p->pSqlite) &&
(p->pSqlite->flags&SQLITE_ReadUncommitted) &&
(eLock==READ_LOCK) &&
iTable!=MASTER_ROOT
){
return SQLITE_OK;
}
for(pIter=pBt->pLock; pIter; pIter=pIter->pNext){
if( pIter->iTable==iTable && pIter->pBtree==p ){
pLock = pIter;
break;
}
}
if( !pLock ){
pLock = (BtLock *)sqliteMalloc(sizeof(BtLock));
if( !pLock ){
return SQLITE_NOMEM;
}
pLock->iTable = iTable;
pLock->pBtree = p;
pLock->pNext = pBt->pLock;
pBt->pLock = pLock;
}
assert( WRITE_LOCK>READ_LOCK );
if( eLock>pLock->eLock ){
pLock->eLock = eLock;
}
return SQLITE_OK;
}
static void unlockAllTables(Btree *p){
BtLock **ppIter = &p->pBt->pLock;
assert( sqlite3ThreadDataReadOnly()->useSharedData || 0==*ppIter );
while( *ppIter ){
BtLock *pLock = *ppIter;
if( pLock->pBtree==p ){
*ppIter = pLock->pNext;
sqliteFree(pLock);
}else{
ppIter = &pLock->pNext;
}
}
}
#endif
static void releasePage(MemPage *pPage);
static int saveCursorPosition(BtCursor *pCur){
int rc;
assert( CURSOR_VALID==pCur->eState );
assert( 0==pCur->pKey );
rc = sqlite3BtreeKeySize(pCur, &pCur->nKey);
if( rc==SQLITE_OK && 0==pCur->pPage->intKey){
void *pKey = sqliteMalloc(pCur->nKey);
if( pKey ){
rc = sqlite3BtreeKey(pCur, 0, pCur->nKey, pKey);
if( rc==SQLITE_OK ){
pCur->pKey = pKey;
}else{
sqliteFree(pKey);
}
}else{
rc = SQLITE_NOMEM;
}
}
assert( !pCur->pPage->intKey || !pCur->pKey );
if( rc==SQLITE_OK ){
releasePage(pCur->pPage);
pCur->pPage = 0;
pCur->eState = CURSOR_REQUIRESEEK;
}
return rc;
}
static int saveAllCursors(BtShared *pBt, Pgno iRoot, BtCursor *pExcept){
BtCursor *p;
for(p=pBt->pCursor; p; p=p->pNext){
if( p!=pExcept && (0==iRoot || p->pgnoRoot==iRoot) &&
p->eState==CURSOR_VALID ){
int rc = saveCursorPosition(p);
if( SQLITE_OK!=rc ){
return rc;
}
}
}
return SQLITE_OK;
}
static void clearCursorPosition(BtCursor *pCur){
sqliteFree(pCur->pKey);
pCur->pKey = 0;
pCur->eState = CURSOR_INVALID;
}
static int restoreOrClearCursorPositionX(BtCursor *pCur){
int rc;
assert( pCur->eState==CURSOR_REQUIRESEEK );
pCur->eState = CURSOR_INVALID;
rc = sqlite3BtreeMoveto(pCur, pCur->pKey, pCur->nKey, 0, &pCur->skip);
if( rc==SQLITE_OK ){
sqliteFree(pCur->pKey);
pCur->pKey = 0;
assert( pCur->eState==CURSOR_VALID || pCur->eState==CURSOR_INVALID );
}
return rc;
}
#define restoreOrClearCursorPosition(p) \
(p->eState==CURSOR_REQUIRESEEK?restoreOrClearCursorPositionX(p):SQLITE_OK)
#ifndef SQLITE_OMIT_AUTOVACUUM
#define PTRMAP_PAGENO(pBt, pgno) ptrmapPageno(pBt, pgno)
#define PTRMAP_PTROFFSET(pBt, pgno) (5*(pgno-ptrmapPageno(pBt, pgno)-1))
#define PTRMAP_ISPAGE(pBt, pgno) (PTRMAP_PAGENO((pBt),(pgno))==(pgno))
static Pgno ptrmapPageno(BtShared *pBt, Pgno pgno){
int nPagesPerMapPage = (pBt->usableSize/5)+1;
int iPtrMap = (pgno-2)/nPagesPerMapPage;
int ret = (iPtrMap*nPagesPerMapPage) + 2;
if( ret==PENDING_BYTE_PAGE(pBt) ){
ret++;
}
return ret;
}
#define PTRMAP_ROOTPAGE 1
#define PTRMAP_FREEPAGE 2
#define PTRMAP_OVERFLOW1 3
#define PTRMAP_OVERFLOW2 4
#define PTRMAP_BTREE 5
static int ptrmapPut(BtShared *pBt, Pgno key, u8 eType, Pgno parent){
DbPage *pDbPage;
u8 *pPtrmap;
Pgno iPtrmap;
int offset;
int rc;
assert( 0==PTRMAP_ISPAGE(pBt, PENDING_BYTE_PAGE(pBt)) );
assert( pBt->autoVacuum );
if( key==0 ){
return SQLITE_CORRUPT_BKPT;
}
iPtrmap = PTRMAP_PAGENO(pBt, key);
rc = sqlite3PagerGet(pBt->pPager, iPtrmap, &pDbPage);
if( rc!=SQLITE_OK ){
return rc;
}
offset = PTRMAP_PTROFFSET(pBt, key);
pPtrmap = (u8 *)sqlite3PagerGetData(pDbPage);
if( eType!=pPtrmap[offset] || get4byte(&pPtrmap[offset+1])!=parent ){
TRACE(("PTRMAP_UPDATE: %d->(%d,%d)\n", key, eType, parent));
rc = sqlite3PagerWrite(pDbPage);
if( rc==SQLITE_OK ){
pPtrmap[offset] = eType;
put4byte(&pPtrmap[offset+1], parent);
}
}
sqlite3PagerUnref(pDbPage);
return rc;
}
static int ptrmapGet(BtShared *pBt, Pgno key, u8 *pEType, Pgno *pPgno){
DbPage *pDbPage;
int iPtrmap;
u8 *pPtrmap;
int offset;
int rc;
iPtrmap = PTRMAP_PAGENO(pBt, key);
rc = sqlite3PagerGet(pBt->pPager, iPtrmap, &pDbPage);
if( rc!=0 ){
return rc;
}
pPtrmap = (u8 *)sqlite3PagerGetData(pDbPage);
offset = PTRMAP_PTROFFSET(pBt, key);
assert( pEType!=0 );
*pEType = pPtrmap[offset];
if( pPgno ) *pPgno = get4byte(&pPtrmap[offset+1]);
sqlite3PagerUnref(pDbPage);
if( *pEType<1 || *pEType>5 ) return SQLITE_CORRUPT_BKPT;
return SQLITE_OK;
}
#endif
static u8 *findCell(MemPage *pPage, int iCell){
u8 *data = pPage->aData;
assert( iCell>=0 );
assert( iCell<get2byte(&data[pPage->hdrOffset+3]) );
return data + get2byte(&data[pPage->cellOffset+2*iCell]);
}
static u8 *findOverflowCell(MemPage *pPage, int iCell){
int i;
for(i=pPage->nOverflow-1; i>=0; i--){
int k;
struct _OvflCell *pOvfl;
pOvfl = &pPage->aOvfl[i];
k = pOvfl->idx;
if( k<=iCell ){
if( k==iCell ){
return pOvfl->pCell;
}
iCell--;
}
}
return findCell(pPage, iCell);
}
static void parseCellPtr(
MemPage *pPage,
u8 *pCell,
CellInfo *pInfo
){
int n;
u32 nPayload;
pInfo->pCell = pCell;
assert( pPage->leaf==0 || pPage->leaf==1 );
n = pPage->childPtrSize;
assert( n==4-4*pPage->leaf );
if( pPage->hasData ){
n += getVarint32(&pCell[n], &nPayload);
}else{
nPayload = 0;
}
pInfo->nData = nPayload;
if( pPage->intKey ){
n += getVarint(&pCell[n], (u64 *)&pInfo->nKey);
}else{
u32 x;
n += getVarint32(&pCell[n], &x);
pInfo->nKey = x;
nPayload += x;
}
pInfo->nPayload = nPayload;
pInfo->nHeader = n;
if( nPayload<=pPage->maxLocal ){
int nSize;
pInfo->nLocal = nPayload;
pInfo->iOverflow = 0;
nSize = nPayload + n;
if( nSize<4 ){
nSize = 4;
}
pInfo->nSize = nSize;
}else{
int minLocal;
int maxLocal;
int surplus;
minLocal = pPage->minLocal;
maxLocal = pPage->maxLocal;
surplus = minLocal + (nPayload - minLocal)%(pPage->pBt->usableSize - 4);
if( surplus <= maxLocal ){
pInfo->nLocal = surplus;
}else{
pInfo->nLocal = minLocal;
}
pInfo->iOverflow = pInfo->nLocal + n;
pInfo->nSize = pInfo->iOverflow + 4;
}
}
static void parseCell(
MemPage *pPage,
int iCell,
CellInfo *pInfo
){
parseCellPtr(pPage, findCell(pPage, iCell), pInfo);
}
#ifndef NDEBUG
static int cellSize(MemPage *pPage, int iCell){
CellInfo info;
parseCell(pPage, iCell, &info);
return info.nSize;
}
#endif
static int cellSizePtr(MemPage *pPage, u8 *pCell){
CellInfo info;
parseCellPtr(pPage, pCell, &info);
return info.nSize;
}
#ifndef SQLITE_OMIT_AUTOVACUUM
static int ptrmapPutOvflPtr(MemPage *pPage, u8 *pCell){
if( pCell ){
CellInfo info;
parseCellPtr(pPage, pCell, &info);
assert( (info.nData+(pPage->intKey?0:info.nKey))==info.nPayload );
if( (info.nData+(pPage->intKey?0:info.nKey))>info.nLocal ){
Pgno ovfl = get4byte(&pCell[info.iOverflow]);
return ptrmapPut(pPage->pBt, ovfl, PTRMAP_OVERFLOW1, pPage->pgno);
}
}
return SQLITE_OK;
}
static int ptrmapPutOvfl(MemPage *pPage, int iCell){
u8 *pCell;
pCell = findOverflowCell(pPage, iCell);
return ptrmapPutOvflPtr(pPage, pCell);
}
#endif
#define btreeIntegrity(p) \
assert( p->inTrans!=TRANS_NONE || p->pBt->nTransaction<p->pBt->nRef ); \
assert( p->pBt->nTransaction<=p->pBt->nRef ); \
assert( p->pBt->inTransaction!=TRANS_NONE || p->pBt->nTransaction==0 ); \
assert( p->pBt->inTransaction>=p->inTrans );
static int defragmentPage(MemPage *pPage){
int i;
int pc;
int addr;
int hdr;
int size;
int usableSize;
int cellOffset;
int brk;
int nCell;
unsigned char *data;
unsigned char *temp;
assert( sqlite3PagerIswriteable(pPage->pDbPage) );
assert( pPage->pBt!=0 );
assert( pPage->pBt->usableSize <= SQLITE_MAX_PAGE_SIZE );
assert( pPage->nOverflow==0 );
temp = sqliteMalloc( pPage->pBt->pageSize );
if( temp==0 ) return SQLITE_NOMEM;
data = pPage->aData;
hdr = pPage->hdrOffset;
cellOffset = pPage->cellOffset;
nCell = pPage->nCell;
assert( nCell==get2byte(&data[hdr+3]) );
usableSize = pPage->pBt->usableSize;
brk = get2byte(&data[hdr+5]);
memcpy(&temp[brk], &data[brk], usableSize - brk);
brk = usableSize;
for(i=0; i<nCell; i++){
u8 *pAddr;
pAddr = &data[cellOffset + i*2];
pc = get2byte(pAddr);
assert( pc<pPage->pBt->usableSize );
size = cellSizePtr(pPage, &temp[pc]);
brk -= size;
memcpy(&data[brk], &temp[pc], size);
put2byte(pAddr, brk);
}
assert( brk>=cellOffset+2*nCell );
put2byte(&data[hdr+5], brk);
data[hdr+1] = 0;
data[hdr+2] = 0;
data[hdr+7] = 0;
addr = cellOffset+2*nCell;
memset(&data[addr], 0, brk-addr);
sqliteFree(temp);
return SQLITE_OK;
}
static int allocateSpace(MemPage *pPage, int nByte){
int addr, pc, hdr;
int size;
int nFrag;
int top;
int nCell;
int cellOffset;
unsigned char *data;
data = pPage->aData;
assert( sqlite3PagerIswriteable(pPage->pDbPage) );
assert( pPage->pBt );
if( nByte<4 ) nByte = 4;
if( pPage->nFree<nByte || pPage->nOverflow>0 ) return 0;
pPage->nFree -= nByte;
hdr = pPage->hdrOffset;
nFrag = data[hdr+7];
if( nFrag<60 ){
addr = hdr+1;
while( (pc = get2byte(&data[addr]))>0 ){
size = get2byte(&data[pc+2]);
if( size>=nByte ){
if( size<nByte+4 ){
memcpy(&data[addr], &data[pc], 2);
data[hdr+7] = nFrag + size - nByte;
return pc;
}else{
put2byte(&data[pc+2], size-nByte);
return pc + size - nByte;
}
}
addr = pc;
}
}
top = get2byte(&data[hdr+5]);
nCell = get2byte(&data[hdr+3]);
cellOffset = pPage->cellOffset;
if( nFrag>=60 || cellOffset + 2*nCell > top - nByte ){
if( defragmentPage(pPage) ) return 0;
top = get2byte(&data[hdr+5]);
}
top -= nByte;
assert( cellOffset + 2*nCell <= top );
put2byte(&data[hdr+5], top);
return top;
}
static void freeSpace(MemPage *pPage, int start, int size){
int addr, pbegin, hdr;
unsigned char *data = pPage->aData;
assert( pPage->pBt!=0 );
assert( sqlite3PagerIswriteable(pPage->pDbPage) );
assert( start>=pPage->hdrOffset+6+(pPage->leaf?0:4) );
assert( (start + size)<=pPage->pBt->usableSize );
if( size<4 ) size = 4;
#ifdef SQLITE_SECURE_DELETE
memset(&data[start], 0, size);
#endif
hdr = pPage->hdrOffset;
addr = hdr + 1;
while( (pbegin = get2byte(&data[addr]))<start && pbegin>0 ){
assert( pbegin<=pPage->pBt->usableSize-4 );
assert( pbegin>addr );
addr = pbegin;
}
assert( pbegin<=pPage->pBt->usableSize-4 );
assert( pbegin>addr || pbegin==0 );
put2byte(&data[addr], start);
put2byte(&data[start], pbegin);
put2byte(&data[start+2], size);
pPage->nFree += size;
addr = pPage->hdrOffset + 1;
while( (pbegin = get2byte(&data[addr]))>0 ){
int pnext, psize;
assert( pbegin>addr );
assert( pbegin<=pPage->pBt->usableSize-4 );
pnext = get2byte(&data[pbegin]);
psize = get2byte(&data[pbegin+2]);
if( pbegin + psize + 3 >= pnext && pnext>0 ){
int frag = pnext - (pbegin+psize);
assert( frag<=data[pPage->hdrOffset+7] );
data[pPage->hdrOffset+7] -= frag;
put2byte(&data[pbegin], get2byte(&data[pnext]));
put2byte(&data[pbegin+2], pnext+get2byte(&data[pnext+2])-pbegin);
}else{
addr = pbegin;
}
}
if( data[hdr+1]==data[hdr+5] && data[hdr+2]==data[hdr+6] ){
int top;
pbegin = get2byte(&data[hdr+1]);
memcpy(&data[hdr+1], &data[pbegin], 2);
top = get2byte(&data[hdr+5]);
put2byte(&data[hdr+5], top + get2byte(&data[pbegin+2]));
}
}
static void decodeFlags(MemPage *pPage, int flagByte){
BtShared *pBt;
assert( pPage->hdrOffset==(pPage->pgno==1 ? 100 : 0) );
pPage->intKey = (flagByte & (PTF_INTKEY|PTF_LEAFDATA))!=0;
pPage->zeroData = (flagByte & PTF_ZERODATA)!=0;
pPage->leaf = (flagByte & PTF_LEAF)!=0;
pPage->childPtrSize = 4*(pPage->leaf==0);
pBt = pPage->pBt;
if( flagByte & PTF_LEAFDATA ){
pPage->leafData = 1;
pPage->maxLocal = pBt->maxLeaf;
pPage->minLocal = pBt->minLeaf;
}else{
pPage->leafData = 0;
pPage->maxLocal = pBt->maxLocal;
pPage->minLocal = pBt->minLocal;
}
pPage->hasData = !(pPage->zeroData || (!pPage->leaf && pPage->leafData));
}
static int initPage(
MemPage *pPage,
MemPage *pParent
){
int pc;
int hdr;
u8 *data;
BtShared *pBt;
int usableSize;
int cellOffset;
int nFree;
int top;
pBt = pPage->pBt;
assert( pBt!=0 );
assert( pParent==0 || pParent->pBt==pBt );
assert( pPage->pgno==sqlite3PagerPagenumber(pPage->pDbPage) );
assert( pPage->aData == &((unsigned char*)pPage)[-pBt->pageSize] );
if( pPage->pParent!=pParent && (pPage->pParent!=0 || pPage->isInit) ){
return SQLITE_CORRUPT_BKPT;
}
if( pPage->isInit ) return SQLITE_OK;
if( pPage->pParent==0 && pParent!=0 ){
pPage->pParent = pParent;
sqlite3PagerRef(pParent->pDbPage);
}
hdr = pPage->hdrOffset;
data = pPage->aData;
decodeFlags(pPage, data[hdr]);
pPage->nOverflow = 0;
pPage->idxShift = 0;
usableSize = pBt->usableSize;
pPage->cellOffset = cellOffset = hdr + 12 - 4*pPage->leaf;
top = get2byte(&data[hdr+5]);
pPage->nCell = get2byte(&data[hdr+3]);
if( pPage->nCell>MX_CELL(pBt) ){
return SQLITE_CORRUPT_BKPT;
}
if( pPage->nCell==0 && pParent!=0 && pParent->pgno!=1 ){
return SQLITE_CORRUPT_BKPT;
}
pc = get2byte(&data[hdr+1]);
nFree = data[hdr+7] + top - (cellOffset + 2*pPage->nCell);
while( pc>0 ){
int next, size;
if( pc>usableSize-4 ){
return SQLITE_CORRUPT_BKPT;
}
next = get2byte(&data[pc]);
size = get2byte(&data[pc+2]);
if( next>0 && next<=pc+size+3 ){
return SQLITE_CORRUPT_BKPT;
}
nFree += size;
pc = next;
}
pPage->nFree = nFree;
if( nFree>=usableSize ){
return SQLITE_CORRUPT_BKPT;
}
pPage->isInit = 1;
return SQLITE_OK;
}
static void zeroPage(MemPage *pPage, int flags){
unsigned char *data = pPage->aData;
BtShared *pBt = pPage->pBt;
int hdr = pPage->hdrOffset;
int first;
assert( sqlite3PagerPagenumber(pPage->pDbPage)==pPage->pgno );
assert( &data[pBt->pageSize] == (unsigned char*)pPage );
assert( sqlite3PagerIswriteable(pPage->pDbPage) );
memset(&data[hdr], 0, pBt->usableSize - hdr);
data[hdr] = flags;
first = hdr + 8 + 4*((flags&PTF_LEAF)==0);
memset(&data[hdr+1], 0, 4);
data[hdr+7] = 0;
put2byte(&data[hdr+5], pBt->usableSize);
pPage->nFree = pBt->usableSize - first;
decodeFlags(pPage, flags);
pPage->hdrOffset = hdr;
pPage->cellOffset = first;
pPage->nOverflow = 0;
pPage->idxShift = 0;
pPage->nCell = 0;
pPage->isInit = 1;
}
static int getPage(BtShared *pBt, Pgno pgno, MemPage **ppPage, int noContent){
int rc;
MemPage *pPage;
DbPage *pDbPage;
rc = sqlite3PagerAcquire(pBt->pPager, pgno, (DbPage**)&pDbPage, noContent);
if( rc ) return rc;
pPage = (MemPage *)sqlite3PagerGetExtra(pDbPage);
pPage->aData = sqlite3PagerGetData(pDbPage);
pPage->pDbPage = pDbPage;
pPage->pBt = pBt;
pPage->pgno = pgno;
pPage->hdrOffset = pPage->pgno==1 ? 100 : 0;
*ppPage = pPage;
return SQLITE_OK;
}
static int getAndInitPage(
BtShared *pBt,
Pgno pgno,
MemPage **ppPage,
MemPage *pParent
){
int rc;
if( pgno==0 ){
return SQLITE_CORRUPT_BKPT;
}
rc = getPage(pBt, pgno, ppPage, 0);
if( rc==SQLITE_OK && (*ppPage)->isInit==0 ){
rc = initPage(*ppPage, pParent);
}
return rc;
}
static void releasePage(MemPage *pPage){
if( pPage ){
assert( pPage->aData );
assert( pPage->pBt );
assert( &pPage->aData[pPage->pBt->pageSize]==(unsigned char*)pPage );
sqlite3PagerUnref(pPage->pDbPage);
}
}
static void pageDestructor(DbPage *pData, int pageSize){
MemPage *pPage;
assert( (pageSize & 7)==0 );
pPage = (MemPage *)sqlite3PagerGetExtra(pData);
if( pPage->pParent ){
MemPage *pParent = pPage->pParent;
pPage->pParent = 0;
releasePage(pParent);
}
pPage->isInit = 0;
}
static void pageReinit(DbPage *pData, int pageSize){
MemPage *pPage;
assert( (pageSize & 7)==0 );
pPage = (MemPage *)sqlite3PagerGetExtra(pData);
if( pPage->isInit ){
pPage->isInit = 0;
initPage(pPage, pPage->pParent);
}
}
int sqlite3BtreeOpen(
const char *zFilename,
sqlite3 *pSqlite,
Btree **ppBtree,
int flags
){
BtShared *pBt;
Btree *p;
int rc;
int nReserve;
unsigned char zDbHeader[100];
#if !defined(SQLITE_OMIT_SHARED_CACHE) && !defined(SQLITE_OMIT_DISKIO)
const ThreadData *pTsdro;
#endif
#if !defined(SQLITE_OMIT_SHARED_CACHE) || !defined(SQLITE_OMIT_AUTOVACUUM)
#ifdef SQLITE_OMIT_MEMORYDB
const int isMemdb = 0;
#else
const int isMemdb = zFilename && !strcmp(zFilename, ":memory:");
#endif
#endif
p = sqliteMalloc(sizeof(Btree));
if( !p ){
return SQLITE_NOMEM;
}
p->inTrans = TRANS_NONE;
p->pSqlite = pSqlite;
#if !defined(SQLITE_OMIT_SHARED_CACHE) && !defined(SQLITE_OMIT_DISKIO)
pTsdro = sqlite3ThreadDataReadOnly();
if( pTsdro->useSharedData && zFilename && !isMemdb ){
char *zFullPathname = sqlite3OsFullPathname(zFilename);
if( !zFullPathname ){
sqliteFree(p);
return SQLITE_NOMEM;
}
for(pBt=pTsdro->pBtree; pBt; pBt=pBt->pNext){
assert( pBt->nRef>0 );
if( 0==strcmp(zFullPathname, sqlite3PagerFilename(pBt->pPager)) ){
p->pBt = pBt;
*ppBtree = p;
pBt->nRef++;
sqliteFree(zFullPathname);
return SQLITE_OK;
}
}
sqliteFree(zFullPathname);
}
#endif
assert( sizeof(i64)==8 || sizeof(i64)==4 );
assert( sizeof(u64)==8 || sizeof(u64)==4 );
assert( sizeof(u32)==4 );
assert( sizeof(u16)==2 );
assert( sizeof(Pgno)==4 );
pBt = sqliteMalloc( sizeof(*pBt) );
if( pBt==0 ){
*ppBtree = 0;
sqliteFree(p);
return SQLITE_NOMEM;
}
rc = sqlite3PagerOpen(&pBt->pPager, zFilename, EXTRA_SIZE, flags);
if( rc==SQLITE_OK ){
rc = sqlite3PagerReadFileheader(pBt->pPager,sizeof(zDbHeader),zDbHeader);
}
if( rc!=SQLITE_OK ){
if( pBt->pPager ){
sqlite3PagerClose(pBt->pPager);
}
sqliteFree(pBt);
sqliteFree(p);
*ppBtree = 0;
return rc;
}
p->pBt = pBt;
sqlite3PagerSetDestructor(pBt->pPager, pageDestructor);
sqlite3PagerSetReiniter(pBt->pPager, pageReinit);
pBt->pCursor = 0;
pBt->pPage1 = 0;
pBt->readOnly = sqlite3PagerIsreadonly(pBt->pPager);
pBt->pageSize = get2byte(&zDbHeader[16]);
if( pBt->pageSize<512 || pBt->pageSize>SQLITE_MAX_PAGE_SIZE
|| ((pBt->pageSize-1)&pBt->pageSize)!=0 ){
pBt->pageSize = SQLITE_DEFAULT_PAGE_SIZE;
pBt->maxEmbedFrac = 64;
pBt->minEmbedFrac = 32;
pBt->minLeafFrac = 32;
#ifndef SQLITE_OMIT_AUTOVACUUM
if( zFilename && !isMemdb ){
pBt->autoVacuum = SQLITE_DEFAULT_AUTOVACUUM;
}
#endif
nReserve = 0;
}else{
nReserve = zDbHeader[20];
pBt->maxEmbedFrac = zDbHeader[21];
pBt->minEmbedFrac = zDbHeader[22];
pBt->minLeafFrac = zDbHeader[23];
pBt->pageSizeFixed = 1;
#ifndef SQLITE_OMIT_AUTOVACUUM
pBt->autoVacuum = (get4byte(&zDbHeader[36 + 4*4])?1:0);
#endif
}
pBt->usableSize = pBt->pageSize - nReserve;
assert( (pBt->pageSize & 7)==0 );
sqlite3PagerSetPagesize(pBt->pPager, pBt->pageSize);
#if !defined(SQLITE_OMIT_SHARED_CACHE) && !defined(SQLITE_OMIT_DISKIO)
if( pTsdro->useSharedData && zFilename && !isMemdb ){
pBt->pNext = pTsdro->pBtree;
sqlite3ThreadData()->pBtree = pBt;
}
#endif
pBt->nRef = 1;
*ppBtree = p;
return SQLITE_OK;
}
int sqlite3BtreeClose(Btree *p){
BtShared *pBt = p->pBt;
BtCursor *pCur;
#ifndef SQLITE_OMIT_SHARED_CACHE
ThreadData *pTsd;
#endif
pCur = pBt->pCursor;
while( pCur ){
BtCursor *pTmp = pCur;
pCur = pCur->pNext;
if( pTmp->pBtree==p ){
sqlite3BtreeCloseCursor(pTmp);
}
}
sqlite3BtreeRollback(p);
sqliteFree(p);
#ifndef SQLITE_OMIT_SHARED_CACHE
assert( pBt->nRef>0 );
pBt->nRef--;
if( pBt->nRef ){
return SQLITE_OK;
}
pTsd = (ThreadData *)sqlite3ThreadDataReadOnly();
if( pTsd->pBtree==pBt ){
assert( pTsd==sqlite3ThreadData() );
pTsd->pBtree = pBt->pNext;
}else{
BtShared *pPrev;
for(pPrev=pTsd->pBtree; pPrev && pPrev->pNext!=pBt; pPrev=pPrev->pNext){}
if( pPrev ){
assert( pTsd==sqlite3ThreadData() );
pPrev->pNext = pBt->pNext;
}
}
#endif
assert( !pBt->pCursor );
sqlite3PagerClose(pBt->pPager);
if( pBt->xFreeSchema && pBt->pSchema ){
pBt->xFreeSchema(pBt->pSchema);
}
sqliteFree(pBt->pSchema);
sqliteFree(pBt);
return SQLITE_OK;
}
int sqlite3BtreeSetBusyHandler(Btree *p, BusyHandler *pHandler){
BtShared *pBt = p->pBt;
pBt->pBusyHandler = pHandler;
sqlite3PagerSetBusyhandler(pBt->pPager, pHandler);
return SQLITE_OK;
}
int sqlite3BtreeSetCacheSize(Btree *p, int mxPage){
BtShared *pBt = p->pBt;
sqlite3PagerSetCachesize(pBt->pPager, mxPage);
return SQLITE_OK;
}
#ifndef SQLITE_OMIT_PAGER_PRAGMAS
int sqlite3BtreeSetSafetyLevel(Btree *p, int level, int fullSync){
BtShared *pBt = p->pBt;
sqlite3PagerSetSafetyLevel(pBt->pPager, level, fullSync);
return SQLITE_OK;
}
#endif
int sqlite3BtreeSyncDisabled(Btree *p){
BtShared *pBt = p->pBt;
assert( pBt && pBt->pPager );
return sqlite3PagerNosync(pBt->pPager);
}
#if !defined(SQLITE_OMIT_PAGER_PRAGMAS) || !defined(SQLITE_OMIT_VACUUM)
int sqlite3BtreeSetPageSize(Btree *p, int pageSize, int nReserve){
BtShared *pBt = p->pBt;
if( pBt->pageSizeFixed ){
return SQLITE_READONLY;
}
if( nReserve<0 ){
nReserve = pBt->pageSize - pBt->usableSize;
}
if( pageSize>=512 && pageSize<=SQLITE_MAX_PAGE_SIZE &&
((pageSize-1)&pageSize)==0 ){
assert( (pageSize & 7)==0 );
assert( !pBt->pPage1 && !pBt->pCursor );
pBt->pageSize = sqlite3PagerSetPagesize(pBt->pPager, pageSize);
}
pBt->usableSize = pBt->pageSize - nReserve;
return SQLITE_OK;
}
int sqlite3BtreeGetPageSize(Btree *p){
return p->pBt->pageSize;
}
int sqlite3BtreeGetReserve(Btree *p){
return p->pBt->pageSize - p->pBt->usableSize;
}
#endif
int sqlite3BtreeSetAutoVacuum(Btree *p, int autoVacuum){
BtShared *pBt = p->pBt;;
#ifdef SQLITE_OMIT_AUTOVACUUM
return SQLITE_READONLY;
#else
if( pBt->pageSizeFixed ){
return SQLITE_READONLY;
}
pBt->autoVacuum = (autoVacuum?1:0);
return SQLITE_OK;
#endif
}
int sqlite3BtreeGetAutoVacuum(Btree *p){
#ifdef SQLITE_OMIT_AUTOVACUUM
return 0;
#else
return p->pBt->autoVacuum;
#endif
}
static int lockBtree(BtShared *pBt){
int rc, pageSize;
MemPage *pPage1;
if( pBt->pPage1 ) return SQLITE_OK;
rc = getPage(pBt, 1, &pPage1, 0);
if( rc!=SQLITE_OK ) return rc;
rc = SQLITE_NOTADB;
if( sqlite3PagerPagecount(pBt->pPager)>0 ){
u8 *page1 = pPage1->aData;
if( memcmp(page1, zMagicHeader, 16)!=0 ){
goto page1_init_failed;
}
if( page1[18]>1 ){
pBt->readOnly = 1;
}
if( page1[19]>1 ){
goto page1_init_failed;
}
pageSize = get2byte(&page1[16]);
if( ((pageSize-1)&pageSize)!=0 || pageSize<512 ){
goto page1_init_failed;
}
assert( (pageSize & 7)==0 );
pBt->pageSize = pageSize;
pBt->usableSize = pageSize - page1[20];
if( pBt->usableSize<500 ){
goto page1_init_failed;
}
pBt->maxEmbedFrac = page1[21];
pBt->minEmbedFrac = page1[22];
pBt->minLeafFrac = page1[23];
#ifndef SQLITE_OMIT_AUTOVACUUM
pBt->autoVacuum = (get4byte(&page1[36 + 4*4])?1:0);
#endif
}
pBt->maxLocal = (pBt->usableSize-12)*pBt->maxEmbedFrac/255 - 23;
pBt->minLocal = (pBt->usableSize-12)*pBt->minEmbedFrac/255 - 23;
pBt->maxLeaf = pBt->usableSize - 35;
pBt->minLeaf = (pBt->usableSize-12)*pBt->minLeafFrac/255 - 23;
if( pBt->minLocal>pBt->maxLocal || pBt->maxLocal<0 ){
goto page1_init_failed;
}
assert( pBt->maxLeaf + 23 <= MX_CELL_SIZE(pBt) );
pBt->pPage1 = pPage1;
return SQLITE_OK;
page1_init_failed:
releasePage(pPage1);
pBt->pPage1 = 0;
return rc;
}
static int lockBtreeWithRetry(Btree *pRef){
int rc = SQLITE_OK;
if( pRef->inTrans==TRANS_NONE ){
u8 inTransaction = pRef->pBt->inTransaction;
btreeIntegrity(pRef);
rc = sqlite3BtreeBeginTrans(pRef, 0);
pRef->pBt->inTransaction = inTransaction;
pRef->inTrans = TRANS_NONE;
if( rc==SQLITE_OK ){
pRef->pBt->nTransaction--;
}
btreeIntegrity(pRef);
}
return rc;
}
static void unlockBtreeIfUnused(BtShared *pBt){
if( pBt->inTransaction==TRANS_NONE && pBt->pCursor==0 && pBt->pPage1!=0 ){
if( sqlite3PagerRefcount(pBt->pPager)>=1 ){
if( pBt->pPage1->aData==0 ){
MemPage *pPage = pBt->pPage1;
pPage->aData = &((u8*)pPage)[-pBt->pageSize];
pPage->pBt = pBt;
pPage->pgno = 1;
}
releasePage(pBt->pPage1);
}
pBt->pPage1 = 0;
pBt->inStmt = 0;
}
}
static int newDatabase(BtShared *pBt){
MemPage *pP1;
unsigned char *data;
int rc;
if( sqlite3PagerPagecount(pBt->pPager)>0 ) return SQLITE_OK;
pP1 = pBt->pPage1;
assert( pP1!=0 );
data = pP1->aData;
rc = sqlite3PagerWrite(pP1->pDbPage);
if( rc ) return rc;
memcpy(data, zMagicHeader, sizeof(zMagicHeader));
assert( sizeof(zMagicHeader)==16 );
put2byte(&data[16], pBt->pageSize);
data[18] = 1;
data[19] = 1;
data[20] = pBt->pageSize - pBt->usableSize;
data[21] = pBt->maxEmbedFrac;
data[22] = pBt->minEmbedFrac;
data[23] = pBt->minLeafFrac;
memset(&data[24], 0, 100-24);
zeroPage(pP1, PTF_INTKEY|PTF_LEAF|PTF_LEAFDATA );
pBt->pageSizeFixed = 1;
#ifndef SQLITE_OMIT_AUTOVACUUM
if( pBt->autoVacuum ){
put4byte(&data[36 + 4*4], 1);
}
#endif
return SQLITE_OK;
}
int sqlite3BtreeBeginTrans(Btree *p, int wrflag){
BtShared *pBt = p->pBt;
int rc = SQLITE_OK;
btreeIntegrity(p);
if( p->inTrans==TRANS_WRITE || (p->inTrans==TRANS_READ && !wrflag) ){
return SQLITE_OK;
}
if( pBt->readOnly && wrflag ){
return SQLITE_READONLY;
}
if( pBt->inTransaction==TRANS_WRITE && wrflag ){
return SQLITE_BUSY;
}
do {
if( pBt->pPage1==0 ){
rc = lockBtree(pBt);
}
if( rc==SQLITE_OK && wrflag ){
if( pBt->readOnly ){
rc = SQLITE_READONLY;
}else{
rc = sqlite3PagerBegin(pBt->pPage1->pDbPage, wrflag>1);
if( rc==SQLITE_OK ){
rc = newDatabase(pBt);
}
}
}
if( rc==SQLITE_OK ){
if( wrflag ) pBt->inStmt = 0;
}else{
unlockBtreeIfUnused(pBt);
}
}while( rc==SQLITE_BUSY && pBt->inTransaction==TRANS_NONE &&
sqlite3InvokeBusyHandler(pBt->pBusyHandler) );
if( rc==SQLITE_OK ){
if( p->inTrans==TRANS_NONE ){
pBt->nTransaction++;
}
p->inTrans = (wrflag?TRANS_WRITE:TRANS_READ);
if( p->inTrans>pBt->inTransaction ){
pBt->inTransaction = p->inTrans;
}
}
btreeIntegrity(p);
return rc;
}
#ifndef SQLITE_OMIT_AUTOVACUUM
static int setChildPtrmaps(MemPage *pPage){
int i;
int nCell;
int rc = SQLITE_OK;
BtShared *pBt = pPage->pBt;
int isInitOrig = pPage->isInit;
Pgno pgno = pPage->pgno;
initPage(pPage, 0);
nCell = pPage->nCell;
for(i=0; i<nCell; i++){
u8 *pCell = findCell(pPage, i);
rc = ptrmapPutOvflPtr(pPage, pCell);
if( rc!=SQLITE_OK ){
goto set_child_ptrmaps_out;
}
if( !pPage->leaf ){
Pgno childPgno = get4byte(pCell);
rc = ptrmapPut(pBt, childPgno, PTRMAP_BTREE, pgno);
if( rc!=SQLITE_OK ) goto set_child_ptrmaps_out;
}
}
if( !pPage->leaf ){
Pgno childPgno = get4byte(&pPage->aData[pPage->hdrOffset+8]);
rc = ptrmapPut(pBt, childPgno, PTRMAP_BTREE, pgno);
}
set_child_ptrmaps_out:
pPage->isInit = isInitOrig;
return rc;
}
static int modifyPagePointer(MemPage *pPage, Pgno iFrom, Pgno iTo, u8 eType){
if( eType==PTRMAP_OVERFLOW2 ){
if( get4byte(pPage->aData)!=iFrom ){
return SQLITE_CORRUPT_BKPT;
}
put4byte(pPage->aData, iTo);
}else{
int isInitOrig = pPage->isInit;
int i;
int nCell;
initPage(pPage, 0);
nCell = pPage->nCell;
for(i=0; i<nCell; i++){
u8 *pCell = findCell(pPage, i);
if( eType==PTRMAP_OVERFLOW1 ){
CellInfo info;
parseCellPtr(pPage, pCell, &info);
if( info.iOverflow ){
if( iFrom==get4byte(&pCell[info.iOverflow]) ){
put4byte(&pCell[info.iOverflow], iTo);
break;
}
}
}else{
if( get4byte(pCell)==iFrom ){
put4byte(pCell, iTo);
break;
}
}
}
if( i==nCell ){
if( eType!=PTRMAP_BTREE ||
get4byte(&pPage->aData[pPage->hdrOffset+8])!=iFrom ){
return SQLITE_CORRUPT_BKPT;
}
put4byte(&pPage->aData[pPage->hdrOffset+8], iTo);
}
pPage->isInit = isInitOrig;
}
return SQLITE_OK;
}
static int relocatePage(
BtShared *pBt,
MemPage *pDbPage,
u8 eType,
Pgno iPtrPage,
Pgno iFreePage
){
MemPage *pPtrPage;
Pgno iDbPage = pDbPage->pgno;
Pager *pPager = pBt->pPager;
int rc;
assert( eType==PTRMAP_OVERFLOW2 || eType==PTRMAP_OVERFLOW1 ||
eType==PTRMAP_BTREE || eType==PTRMAP_ROOTPAGE );
TRACE(("AUTOVACUUM: Moving %d to free page %d (ptr page %d type %d)\n",
iDbPage, iFreePage, iPtrPage, eType));
rc = sqlite3PagerMovepage(pPager, pDbPage->pDbPage, iFreePage);
if( rc!=SQLITE_OK ){
return rc;
}
pDbPage->pgno = iFreePage;
if( eType==PTRMAP_BTREE || eType==PTRMAP_ROOTPAGE ){
rc = setChildPtrmaps(pDbPage);
if( rc!=SQLITE_OK ){
return rc;
}
}else{
Pgno nextOvfl = get4byte(pDbPage->aData);
if( nextOvfl!=0 ){
rc = ptrmapPut(pBt, nextOvfl, PTRMAP_OVERFLOW2, iFreePage);
if( rc!=SQLITE_OK ){
return rc;
}
}
}
if( eType!=PTRMAP_ROOTPAGE ){
rc = getPage(pBt, iPtrPage, &pPtrPage, 0);
if( rc!=SQLITE_OK ){
return rc;
}
rc = sqlite3PagerWrite(pPtrPage->pDbPage);
if( rc!=SQLITE_OK ){
releasePage(pPtrPage);
return rc;
}
rc = modifyPagePointer(pPtrPage, iDbPage, iFreePage, eType);
releasePage(pPtrPage);
if( rc==SQLITE_OK ){
rc = ptrmapPut(pBt, iFreePage, eType, iPtrPage);
}
}
return rc;
}
static int allocateBtreePage(BtShared *, MemPage **, Pgno *, Pgno, u8);
static int autoVacuumCommit(BtShared *pBt, Pgno *pnTrunc){
Pager *pPager = pBt->pPager;
Pgno nFreeList;
int nPtrMap;
Pgno origSize;
Pgno finSize;
int rc;
u8 eType;
int pgsz = pBt->pageSize;
Pgno iDbPage;
MemPage *pDbMemPage = 0;
Pgno iPtrPage;
Pgno iFreePage;
MemPage *pFreeMemPage = 0;
#ifndef NDEBUG
int nRef = sqlite3PagerRefcount(pPager);
#endif
assert( pBt->autoVacuum );
if( PTRMAP_ISPAGE(pBt, sqlite3PagerPagecount(pPager)) ){
return SQLITE_CORRUPT_BKPT;
}
nFreeList = get4byte(&pBt->pPage1->aData[36]);
if( nFreeList==0 ){
*pnTrunc = 0;
return SQLITE_OK;
}
origSize = sqlite3PagerPagecount(pPager);
if( origSize==PENDING_BYTE_PAGE(pBt) ){
origSize--;
}
nPtrMap = (nFreeList-origSize+PTRMAP_PAGENO(pBt, origSize)+pgsz/5)/(pgsz/5);
finSize = origSize - nFreeList - nPtrMap;
if( origSize>PENDING_BYTE_PAGE(pBt) && finSize<=PENDING_BYTE_PAGE(pBt) ){
finSize--;
}
while( PTRMAP_ISPAGE(pBt, finSize) || finSize==PENDING_BYTE_PAGE(pBt) ){
finSize--;
}
TRACE(("AUTOVACUUM: Begin (db size %d->%d)\n", origSize, finSize));
for( iDbPage=finSize+1; iDbPage<=origSize; iDbPage++ ){
if( PTRMAP_ISPAGE(pBt, iDbPage) || iDbPage==PENDING_BYTE_PAGE(pBt) ){
continue;
}
rc = ptrmapGet(pBt, iDbPage, &eType, &iPtrPage);
if( rc!=SQLITE_OK ) goto autovacuum_out;
if( eType==PTRMAP_ROOTPAGE ){
rc = SQLITE_CORRUPT_BKPT;
goto autovacuum_out;
}
if( eType==PTRMAP_FREEPAGE ){
continue;
}
rc = getPage(pBt, iDbPage, &pDbMemPage, 0);
if( rc!=SQLITE_OK ) goto autovacuum_out;
do{
if( pFreeMemPage ){
releasePage(pFreeMemPage);
pFreeMemPage = 0;
}
rc = allocateBtreePage(pBt, &pFreeMemPage, &iFreePage, 0, 0);
if( rc!=SQLITE_OK ){
releasePage(pDbMemPage);
goto autovacuum_out;
}
assert( iFreePage<=origSize );
}while( iFreePage>finSize );
releasePage(pFreeMemPage);
pFreeMemPage = 0;
rc = relocatePage(pBt, pDbMemPage, eType, iPtrPage, iFreePage);
releasePage(pDbMemPage);
if( rc!=SQLITE_OK ) goto autovacuum_out;
}
rc = sqlite3PagerWrite(pBt->pPage1->pDbPage);
if( rc!=SQLITE_OK ) goto autovacuum_out;
put4byte(&pBt->pPage1->aData[32], 0);
put4byte(&pBt->pPage1->aData[36], 0);
*pnTrunc = finSize;
assert( finSize!=PENDING_BYTE_PAGE(pBt) );
autovacuum_out:
assert( nRef==sqlite3PagerRefcount(pPager) );
if( rc!=SQLITE_OK ){
sqlite3PagerRollback(pPager);
}
return rc;
}
#endif
int sqlite3BtreeCommitPhaseOne(Btree *p, const char *zMaster){
int rc = SQLITE_OK;
if( p->inTrans==TRANS_WRITE ){
BtShared *pBt = p->pBt;
Pgno nTrunc = 0;
#ifndef SQLITE_OMIT_AUTOVACUUM
if( pBt->autoVacuum ){
rc = autoVacuumCommit(pBt, &nTrunc);
if( rc!=SQLITE_OK ){
return rc;
}
}
#endif
rc = sqlite3PagerCommitPhaseOne(pBt->pPager, zMaster, nTrunc);
}
return rc;
}
int sqlite3BtreeCommitPhaseTwo(Btree *p){
BtShared *pBt = p->pBt;
btreeIntegrity(p);
if( p->inTrans==TRANS_WRITE ){
int rc;
assert( pBt->inTransaction==TRANS_WRITE );
assert( pBt->nTransaction>0 );
rc = sqlite3PagerCommitPhaseTwo(pBt->pPager);
if( rc!=SQLITE_OK ){
return rc;
}
pBt->inTransaction = TRANS_READ;
pBt->inStmt = 0;
}
unlockAllTables(p);
if( p->inTrans!=TRANS_NONE ){
pBt->nTransaction--;
if( 0==pBt->nTransaction ){
pBt->inTransaction = TRANS_NONE;
}
}
p->inTrans = TRANS_NONE;
unlockBtreeIfUnused(pBt);
btreeIntegrity(p);
return SQLITE_OK;
}
int sqlite3BtreeCommit(Btree *p){
int rc;
rc = sqlite3BtreeCommitPhaseOne(p, 0);
if( rc==SQLITE_OK ){
rc = sqlite3BtreeCommitPhaseTwo(p);
}
return rc;
}
#ifndef NDEBUG
static int countWriteCursors(BtShared *pBt){
BtCursor *pCur;
int r = 0;
for(pCur=pBt->pCursor; pCur; pCur=pCur->pNext){
if( pCur->wrFlag ) r++;
}
return r;
}
#endif
#if defined(SQLITE_TEST) || defined(SQLITE_DEBUG)
void sqlite3BtreeCursorList(Btree *p){
BtCursor *pCur;
BtShared *pBt = p->pBt;
for(pCur=pBt->pCursor; pCur; pCur=pCur->pNext){
MemPage *pPage = pCur->pPage;
char *zMode = pCur->wrFlag ? "rw" : "ro";
sqlite3DebugPrintf("CURSOR %p rooted at %4d(%s) currently at %d.%d%s\n",
pCur, pCur->pgnoRoot, zMode,
pPage ? pPage->pgno : 0, pCur->idx,
(pCur->eState==CURSOR_VALID) ? "" : " eof"
);
}
}
#endif
int sqlite3BtreeRollback(Btree *p){
int rc;
BtShared *pBt = p->pBt;
MemPage *pPage1;
rc = saveAllCursors(pBt, 0, 0);
#ifndef SQLITE_OMIT_SHARED_CACHE
if( rc!=SQLITE_OK ){
while( pBt->pCursor ){
sqlite3 *db = pBt->pCursor->pBtree->pSqlite;
if( db ){
sqlite3AbortOtherActiveVdbes(db, 0);
}
}
}
#endif
btreeIntegrity(p);
unlockAllTables(p);
if( p->inTrans==TRANS_WRITE ){
int rc2;
assert( TRANS_WRITE==pBt->inTransaction );
rc2 = sqlite3PagerRollback(pBt->pPager);
if( rc2!=SQLITE_OK ){
rc = rc2;
}
if( getPage(pBt, 1, &pPage1, 0)==SQLITE_OK ){
releasePage(pPage1);
}
assert( countWriteCursors(pBt)==0 );
pBt->inTransaction = TRANS_READ;
}
if( p->inTrans!=TRANS_NONE ){
assert( pBt->nTransaction>0 );
pBt->nTransaction--;
if( 0==pBt->nTransaction ){
pBt->inTransaction = TRANS_NONE;
}
}
p->inTrans = TRANS_NONE;
pBt->inStmt = 0;
unlockBtreeIfUnused(pBt);
btreeIntegrity(p);
return rc;
}
int sqlite3BtreeBeginStmt(Btree *p){
int rc;
BtShared *pBt = p->pBt;
if( (p->inTrans!=TRANS_WRITE) || pBt->inStmt ){
return pBt->readOnly ? SQLITE_READONLY : SQLITE_ERROR;
}
assert( pBt->inTransaction==TRANS_WRITE );
rc = pBt->readOnly ? SQLITE_OK : sqlite3PagerStmtBegin(pBt->pPager);
pBt->inStmt = 1;
return rc;
}
int sqlite3BtreeCommitStmt(Btree *p){
int rc;
BtShared *pBt = p->pBt;
if( pBt->inStmt && !pBt->readOnly ){
rc = sqlite3PagerStmtCommit(pBt->pPager);
}else{
rc = SQLITE_OK;
}
pBt->inStmt = 0;
return rc;
}
int sqlite3BtreeRollbackStmt(Btree *p){
int rc = SQLITE_OK;
BtShared *pBt = p->pBt;
sqlite3MallocDisallow();
if( pBt->inStmt && !pBt->readOnly ){
rc = sqlite3PagerStmtRollback(pBt->pPager);
assert( countWriteCursors(pBt)==0 );
pBt->inStmt = 0;
}
sqlite3MallocAllow();
return rc;
}
static int dfltCompare(
void *NotUsed,
int n1, const void *p1,
int n2, const void *p2
){
int c;
c = memcmp(p1, p2, n1<n2 ? n1 : n2);
if( c==0 ){
c = n1 - n2;
}
return c;
}
int sqlite3BtreeCursor(
Btree *p,
int iTable,
int wrFlag,
int (*xCmp)(void*,int,const void*,int,const void*),
void *pArg,
BtCursor **ppCur
){
int rc;
BtCursor *pCur;
BtShared *pBt = p->pBt;
*ppCur = 0;
if( wrFlag ){
if( pBt->readOnly ){
return SQLITE_READONLY;
}
if( checkReadLocks(p, iTable, 0) ){
return SQLITE_LOCKED;
}
}
if( pBt->pPage1==0 ){
rc = lockBtreeWithRetry(p);
if( rc!=SQLITE_OK ){
return rc;
}
if( pBt->readOnly && wrFlag ){
return SQLITE_READONLY;
}
}
pCur = sqliteMalloc( sizeof(*pCur) );
if( pCur==0 ){
rc = SQLITE_NOMEM;
goto create_cursor_exception;
}
pCur->pgnoRoot = (Pgno)iTable;
if( iTable==1 && sqlite3PagerPagecount(pBt->pPager)==0 ){
rc = SQLITE_EMPTY;
goto create_cursor_exception;
}
rc = getAndInitPage(pBt, pCur->pgnoRoot, &pCur->pPage, 0);
if( rc!=SQLITE_OK ){
goto create_cursor_exception;
}
pCur->xCompare = xCmp ? xCmp : dfltCompare;
pCur->pArg = pArg;
pCur->pBtree = p;
pCur->wrFlag = wrFlag;
pCur->pNext = pBt->pCursor;
if( pCur->pNext ){
pCur->pNext->pPrev = pCur;
}
pBt->pCursor = pCur;
pCur->eState = CURSOR_INVALID;
*ppCur = pCur;
return SQLITE_OK;
create_cursor_exception:
if( pCur ){
releasePage(pCur->pPage);
sqliteFree(pCur);
}
unlockBtreeIfUnused(pBt);
return rc;
}
#if 0
void sqlite3BtreeSetCompare(
BtCursor *pCur,
int(*xCmp)(void*,int,const void*,int,const void*),
void *pArg
){
pCur->xCompare = xCmp ? xCmp : dfltCompare;
pCur->pArg = pArg;
}
#endif
int sqlite3BtreeCloseCursor(BtCursor *pCur){
BtShared *pBt = pCur->pBtree->pBt;
clearCursorPosition(pCur);
if( pCur->pPrev ){
pCur->pPrev->pNext = pCur->pNext;
}else{
pBt->pCursor = pCur->pNext;
}
if( pCur->pNext ){
pCur->pNext->pPrev = pCur->pPrev;
}
releasePage(pCur->pPage);
unlockBtreeIfUnused(pBt);
sqliteFree(pCur);
return SQLITE_OK;
}
static void getTempCursor(BtCursor *pCur, BtCursor *pTempCur){
memcpy(pTempCur, pCur, sizeof(*pCur));
pTempCur->pNext = 0;
pTempCur->pPrev = 0;
if( pTempCur->pPage ){
sqlite3PagerRef(pTempCur->pPage->pDbPage);
}
}
static void releaseTempCursor(BtCursor *pCur){
if( pCur->pPage ){
sqlite3PagerUnref(pCur->pPage->pDbPage);
}
}
static void getCellInfo(BtCursor *pCur){
if( pCur->info.nSize==0 ){
parseCell(pCur->pPage, pCur->idx, &pCur->info);
}else{
#ifndef NDEBUG
CellInfo info;
memset(&info, 0, sizeof(info));
parseCell(pCur->pPage, pCur->idx, &info);
assert( memcmp(&info, &pCur->info, sizeof(info))==0 );
#endif
}
}
int sqlite3BtreeKeySize(BtCursor *pCur, i64 *pSize){
int rc = restoreOrClearCursorPosition(pCur);
if( rc==SQLITE_OK ){
assert( pCur->eState==CURSOR_INVALID || pCur->eState==CURSOR_VALID );
if( pCur->eState==CURSOR_INVALID ){
*pSize = 0;
}else{
getCellInfo(pCur);
*pSize = pCur->info.nKey;
}
}
return rc;
}
int sqlite3BtreeDataSize(BtCursor *pCur, u32 *pSize){
int rc = restoreOrClearCursorPosition(pCur);
if( rc==SQLITE_OK ){
assert( pCur->eState==CURSOR_INVALID || pCur->eState==CURSOR_VALID );
if( pCur->eState==CURSOR_INVALID ){
*pSize = 0;
}else{
getCellInfo(pCur);
*pSize = pCur->info.nData;
}
}
return rc;
}
static int getPayload(
BtCursor *pCur,
int offset,
int amt,
unsigned char *pBuf,
int skipKey
){
unsigned char *aPayload;
Pgno nextPage;
int rc;
MemPage *pPage;
BtShared *pBt;
int ovflSize;
u32 nKey;
assert( pCur!=0 && pCur->pPage!=0 );
assert( pCur->eState==CURSOR_VALID );
pBt = pCur->pBtree->pBt;
pPage = pCur->pPage;
assert( pCur->idx>=0 && pCur->idx<pPage->nCell );
getCellInfo(pCur);
aPayload = pCur->info.pCell + pCur->info.nHeader;
if( pPage->intKey ){
nKey = 0;
}else{
nKey = pCur->info.nKey;
}
assert( offset>=0 );
if( skipKey ){
offset += nKey;
}
if( offset+amt > nKey+pCur->info.nData ){
return SQLITE_ERROR;
}
if( offset<pCur->info.nLocal ){
int a = amt;
if( a+offset>pCur->info.nLocal ){
a = pCur->info.nLocal - offset;
}
memcpy(pBuf, &aPayload[offset], a);
if( a==amt ){
return SQLITE_OK;
}
offset = 0;
pBuf += a;
amt -= a;
}else{
offset -= pCur->info.nLocal;
}
ovflSize = pBt->usableSize - 4;
if( amt>0 ){
nextPage = get4byte(&aPayload[pCur->info.nLocal]);
while( amt>0 && nextPage ){
DbPage *pDbPage;
rc = sqlite3PagerGet(pBt->pPager, nextPage, &pDbPage);
if( rc!=0 ){
return rc;
}
aPayload = sqlite3PagerGetData(pDbPage);
nextPage = get4byte(aPayload);
if( offset<ovflSize ){
int a = amt;
if( a + offset > ovflSize ){
a = ovflSize - offset;
}
memcpy(pBuf, &aPayload[offset+4], a);
offset = 0;
amt -= a;
pBuf += a;
}else{
offset -= ovflSize;
}
sqlite3PagerUnref(pDbPage);
}
}
if( amt>0 ){
return SQLITE_CORRUPT_BKPT;
}
return SQLITE_OK;
}
int sqlite3BtreeKey(BtCursor *pCur, u32 offset, u32 amt, void *pBuf){
int rc = restoreOrClearCursorPosition(pCur);
if( rc==SQLITE_OK ){
assert( pCur->eState==CURSOR_VALID );
assert( pCur->pPage!=0 );
if( pCur->pPage->intKey ){
return SQLITE_CORRUPT_BKPT;
}
assert( pCur->pPage->intKey==0 );
assert( pCur->idx>=0 && pCur->idx<pCur->pPage->nCell );
rc = getPayload(pCur, offset, amt, (unsigned char*)pBuf, 0);
}
return rc;
}
int sqlite3BtreeData(BtCursor *pCur, u32 offset, u32 amt, void *pBuf){
int rc = restoreOrClearCursorPosition(pCur);
if( rc==SQLITE_OK ){
assert( pCur->eState==CURSOR_VALID );
assert( pCur->pPage!=0 );
assert( pCur->idx>=0 && pCur->idx<pCur->pPage->nCell );
rc = getPayload(pCur, offset, amt, pBuf, 1);
}
return rc;
}
static const unsigned char *fetchPayload(
BtCursor *pCur,
int *pAmt,
int skipKey
){
unsigned char *aPayload;
MemPage *pPage;
u32 nKey;
int nLocal;
assert( pCur!=0 && pCur->pPage!=0 );
assert( pCur->eState==CURSOR_VALID );
pPage = pCur->pPage;
assert( pCur->idx>=0 && pCur->idx<pPage->nCell );
getCellInfo(pCur);
aPayload = pCur->info.pCell;
aPayload += pCur->info.nHeader;
if( pPage->intKey ){
nKey = 0;
}else{
nKey = pCur->info.nKey;
}
if( skipKey ){
aPayload += nKey;
nLocal = pCur->info.nLocal - nKey;
}else{
nLocal = pCur->info.nLocal;
if( nLocal>nKey ){
nLocal = nKey;
}
}
*pAmt = nLocal;
return aPayload;
}
const void *sqlite3BtreeKeyFetch(BtCursor *pCur, int *pAmt){
if( pCur->eState==CURSOR_VALID ){
return (const void*)fetchPayload(pCur, pAmt, 0);
}
return 0;
}
const void *sqlite3BtreeDataFetch(BtCursor *pCur, int *pAmt){
if( pCur->eState==CURSOR_VALID ){
return (const void*)fetchPayload(pCur, pAmt, 1);
}
return 0;
}
static int moveToChild(BtCursor *pCur, u32 newPgno){
int rc;
MemPage *pNewPage;
MemPage *pOldPage;
BtShared *pBt = pCur->pBtree->pBt;
assert( pCur->eState==CURSOR_VALID );
rc = getAndInitPage(pBt, newPgno, &pNewPage, pCur->pPage);
if( rc ) return rc;
pNewPage->idxParent = pCur->idx;
pOldPage = pCur->pPage;
pOldPage->idxShift = 0;
releasePage(pOldPage);
pCur->pPage = pNewPage;
pCur->idx = 0;
pCur->info.nSize = 0;
if( pNewPage->nCell<1 ){
return SQLITE_CORRUPT_BKPT;
}
return SQLITE_OK;
}
static int isRootPage(MemPage *pPage){
MemPage *pParent = pPage->pParent;
if( pParent==0 ) return 1;
if( pParent->pgno>1 ) return 0;
if( get2byte(&pParent->aData[pParent->hdrOffset+3])==0 ) return 1;
return 0;
}
static void moveToParent(BtCursor *pCur){
MemPage *pParent;
MemPage *pPage;
int idxParent;
assert( pCur->eState==CURSOR_VALID );
pPage = pCur->pPage;
assert( pPage!=0 );
assert( !isRootPage(pPage) );
pParent = pPage->pParent;
assert( pParent!=0 );
idxParent = pPage->idxParent;
sqlite3PagerRef(pParent->pDbPage);
releasePage(pPage);
pCur->pPage = pParent;
pCur->info.nSize = 0;
assert( pParent->idxShift==0 );
pCur->idx = idxParent;
}
static int moveToRoot(BtCursor *pCur){
MemPage *pRoot;
int rc = SQLITE_OK;
BtShared *pBt = pCur->pBtree->pBt;
if( pCur->eState==CURSOR_REQUIRESEEK ){
clearCursorPosition(pCur);
}
pRoot = pCur->pPage;
if( pRoot && pRoot->pgno==pCur->pgnoRoot ){
assert( pRoot->isInit );
}else{
if(
SQLITE_OK!=(rc = getAndInitPage(pBt, pCur->pgnoRoot, &pRoot, 0))
){
pCur->eState = CURSOR_INVALID;
return rc;
}
releasePage(pCur->pPage);
pCur->pPage = pRoot;
}
pCur->idx = 0;
pCur->info.nSize = 0;
if( pRoot->nCell==0 && !pRoot->leaf ){
Pgno subpage;
assert( pRoot->pgno==1 );
subpage = get4byte(&pRoot->aData[pRoot->hdrOffset+8]);
assert( subpage>0 );
pCur->eState = CURSOR_VALID;
rc = moveToChild(pCur, subpage);
}
pCur->eState = ((pCur->pPage->nCell>0)?CURSOR_VALID:CURSOR_INVALID);
return rc;
}
static int moveToLeftmost(BtCursor *pCur){
Pgno pgno;
int rc;
MemPage *pPage;
assert( pCur->eState==CURSOR_VALID );
while( !(pPage = pCur->pPage)->leaf ){
assert( pCur->idx>=0 && pCur->idx<pPage->nCell );
pgno = get4byte(findCell(pPage, pCur->idx));
rc = moveToChild(pCur, pgno);
if( rc ) return rc;
}
return SQLITE_OK;
}
static int moveToRightmost(BtCursor *pCur){
Pgno pgno;
int rc;
MemPage *pPage;
assert( pCur->eState==CURSOR_VALID );
while( !(pPage = pCur->pPage)->leaf ){
pgno = get4byte(&pPage->aData[pPage->hdrOffset+8]);
pCur->idx = pPage->nCell;
rc = moveToChild(pCur, pgno);
if( rc ) return rc;
}
pCur->idx = pPage->nCell - 1;
pCur->info.nSize = 0;
return SQLITE_OK;
}
int sqlite3BtreeFirst(BtCursor *pCur, int *pRes){
int rc;
rc = moveToRoot(pCur);
if( rc ) return rc;
if( pCur->eState==CURSOR_INVALID ){
assert( pCur->pPage->nCell==0 );
*pRes = 1;
return SQLITE_OK;
}
assert( pCur->pPage->nCell>0 );
*pRes = 0;
rc = moveToLeftmost(pCur);
return rc;
}
int sqlite3BtreeLast(BtCursor *pCur, int *pRes){
int rc;
rc = moveToRoot(pCur);
if( rc ) return rc;
if( CURSOR_INVALID==pCur->eState ){
assert( pCur->pPage->nCell==0 );
*pRes = 1;
return SQLITE_OK;
}
assert( pCur->eState==CURSOR_VALID );
*pRes = 0;
rc = moveToRightmost(pCur);
return rc;
}
int sqlite3BtreeMoveto(
BtCursor *pCur,
const void *pKey,
i64 nKey,
int biasRight,
int *pRes
){
int rc;
rc = moveToRoot(pCur);
if( rc ) return rc;
assert( pCur->pPage );
assert( pCur->pPage->isInit );
if( pCur->eState==CURSOR_INVALID ){
*pRes = -1;
assert( pCur->pPage->nCell==0 );
return SQLITE_OK;
}
for(;;){
int lwr, upr;
Pgno chldPg;
MemPage *pPage = pCur->pPage;
int c = -1;
lwr = 0;
upr = pPage->nCell-1;
if( !pPage->intKey && pKey==0 ){
return SQLITE_CORRUPT_BKPT;
}
if( biasRight ){
pCur->idx = upr;
}else{
pCur->idx = (upr+lwr)/2;
}
if( lwr<=upr ) for(;;){
void *pCellKey;
i64 nCellKey;
pCur->info.nSize = 0;
if( pPage->intKey ){
u8 *pCell;
pCell = findCell(pPage, pCur->idx) + pPage->childPtrSize;
if( pPage->hasData ){
u32 dummy;
pCell += getVarint32(pCell, &dummy);
}
getVarint(pCell, (u64 *)&nCellKey);
if( nCellKey<nKey ){
c = -1;
}else if( nCellKey>nKey ){
c = +1;
}else{
c = 0;
}
}else{
int available;
pCellKey = (void *)fetchPayload(pCur, &available, 0);
nCellKey = pCur->info.nKey;
if( available>=nCellKey ){
c = pCur->xCompare(pCur->pArg, nCellKey, pCellKey, nKey, pKey);
}else{
pCellKey = sqliteMallocRaw( nCellKey );
if( pCellKey==0 ) return SQLITE_NOMEM;
rc = sqlite3BtreeKey(pCur, 0, nCellKey, (void *)pCellKey);
c = pCur->xCompare(pCur->pArg, nCellKey, pCellKey, nKey, pKey);
sqliteFree(pCellKey);
if( rc ) return rc;
}
}
if( c==0 ){
if( pPage->leafData && !pPage->leaf ){
lwr = pCur->idx;
upr = lwr - 1;
break;
}else{
if( pRes ) *pRes = 0;
return SQLITE_OK;
}
}
if( c<0 ){
lwr = pCur->idx+1;
}else{
upr = pCur->idx-1;
}
if( lwr>upr ){
break;
}
pCur->idx = (lwr+upr)/2;
}
assert( lwr==upr+1 );
assert( pPage->isInit );
if( pPage->leaf ){
chldPg = 0;
}else if( lwr>=pPage->nCell ){
chldPg = get4byte(&pPage->aData[pPage->hdrOffset+8]);
}else{
chldPg = get4byte(findCell(pPage, lwr));
}
if( chldPg==0 ){
assert( pCur->idx>=0 && pCur->idx<pCur->pPage->nCell );
if( pRes ) *pRes = c;
return SQLITE_OK;
}
pCur->idx = lwr;
pCur->info.nSize = 0;
rc = moveToChild(pCur, chldPg);
if( rc ){
return rc;
}
}
}
int sqlite3BtreeEof(BtCursor *pCur){
return (CURSOR_VALID!=pCur->eState);
}
int sqlite3BtreeNext(BtCursor *pCur, int *pRes){
int rc;
MemPage *pPage;
rc = restoreOrClearCursorPosition(pCur);
if( rc!=SQLITE_OK ){
return rc;
}
assert( pRes!=0 );
pPage = pCur->pPage;
if( CURSOR_INVALID==pCur->eState ){
*pRes = 1;
return SQLITE_OK;
}
if( pCur->skip>0 ){
pCur->skip = 0;
*pRes = 0;
return SQLITE_OK;
}
pCur->skip = 0;
assert( pPage->isInit );
assert( pCur->idx<pPage->nCell );
pCur->idx++;
pCur->info.nSize = 0;
if( pCur->idx>=pPage->nCell ){
if( !pPage->leaf ){
rc = moveToChild(pCur, get4byte(&pPage->aData[pPage->hdrOffset+8]));
if( rc ) return rc;
rc = moveToLeftmost(pCur);
*pRes = 0;
return rc;
}
do{
if( isRootPage(pPage) ){
*pRes = 1;
pCur->eState = CURSOR_INVALID;
return SQLITE_OK;
}
moveToParent(pCur);
pPage = pCur->pPage;
}while( pCur->idx>=pPage->nCell );
*pRes = 0;
if( pPage->leafData ){
rc = sqlite3BtreeNext(pCur, pRes);
}else{
rc = SQLITE_OK;
}
return rc;
}
*pRes = 0;
if( pPage->leaf ){
return SQLITE_OK;
}
rc = moveToLeftmost(pCur);
return rc;
}
int sqlite3BtreePrevious(BtCursor *pCur, int *pRes){
int rc;
Pgno pgno;
MemPage *pPage;
rc = restoreOrClearCursorPosition(pCur);
if( rc!=SQLITE_OK ){
return rc;
}
if( CURSOR_INVALID==pCur->eState ){
*pRes = 1;
return SQLITE_OK;
}
if( pCur->skip<0 ){
pCur->skip = 0;
*pRes = 0;
return SQLITE_OK;
}
pCur->skip = 0;
pPage = pCur->pPage;
assert( pPage->isInit );
assert( pCur->idx>=0 );
if( !pPage->leaf ){
pgno = get4byte( findCell(pPage, pCur->idx) );
rc = moveToChild(pCur, pgno);
if( rc ) return rc;
rc = moveToRightmost(pCur);
}else{
while( pCur->idx==0 ){
if( isRootPage(pPage) ){
pCur->eState = CURSOR_INVALID;
*pRes = 1;
return SQLITE_OK;
}
moveToParent(pCur);
pPage = pCur->pPage;
}
pCur->idx--;
pCur->info.nSize = 0;
if( pPage->leafData && !pPage->leaf ){
rc = sqlite3BtreePrevious(pCur, pRes);
}else{
rc = SQLITE_OK;
}
}
*pRes = 0;
return rc;
}
static int allocateBtreePage(
BtShared *pBt,
MemPage **ppPage,
Pgno *pPgno,
Pgno nearby,
u8 exact
){
MemPage *pPage1;
int rc;
int n;
int k;
MemPage *pTrunk = 0;
MemPage *pPrevTrunk = 0;
pPage1 = pBt->pPage1;
n = get4byte(&pPage1->aData[36]);
if( n>0 ){
Pgno iTrunk;
u8 searchList = 0;
#ifndef SQLITE_OMIT_AUTOVACUUM
if( exact ){
u8 eType;
assert( nearby>0 );
assert( pBt->autoVacuum );
rc = ptrmapGet(pBt, nearby, &eType, 0);
if( rc ) return rc;
if( eType==PTRMAP_FREEPAGE ){
searchList = 1;
}
*pPgno = nearby;
}
#endif
rc = sqlite3PagerWrite(pPage1->pDbPage);
if( rc ) return rc;
put4byte(&pPage1->aData[36], n-1);
do {
pPrevTrunk = pTrunk;
if( pPrevTrunk ){
iTrunk = get4byte(&pPrevTrunk->aData[0]);
}else{
iTrunk = get4byte(&pPage1->aData[32]);
}
rc = getPage(pBt, iTrunk, &pTrunk, 0);
if( rc ){
pTrunk = 0;
goto end_allocate_page;
}
k = get4byte(&pTrunk->aData[4]);
if( k==0 && !searchList ){
assert( pPrevTrunk==0 );
rc = sqlite3PagerWrite(pTrunk->pDbPage);
if( rc ){
goto end_allocate_page;
}
*pPgno = iTrunk;
memcpy(&pPage1->aData[32], &pTrunk->aData[0], 4);
*ppPage = pTrunk;
pTrunk = 0;
TRACE(("ALLOCATE: %d trunk - %d free pages left\n", *pPgno, n-1));
}else if( k>pBt->usableSize/4 - 8 ){
rc = SQLITE_CORRUPT_BKPT;
goto end_allocate_page;
#ifndef SQLITE_OMIT_AUTOVACUUM
}else if( searchList && nearby==iTrunk ){
assert( *pPgno==iTrunk );
*ppPage = pTrunk;
searchList = 0;
rc = sqlite3PagerWrite(pTrunk->pDbPage);
if( rc ){
goto end_allocate_page;
}
if( k==0 ){
if( !pPrevTrunk ){
memcpy(&pPage1->aData[32], &pTrunk->aData[0], 4);
}else{
memcpy(&pPrevTrunk->aData[0], &pTrunk->aData[0], 4);
}
}else{
MemPage *pNewTrunk;
Pgno iNewTrunk = get4byte(&pTrunk->aData[8]);
rc = getPage(pBt, iNewTrunk, &pNewTrunk, 0);
if( rc!=SQLITE_OK ){
goto end_allocate_page;
}
rc = sqlite3PagerWrite(pNewTrunk->pDbPage);
if( rc!=SQLITE_OK ){
releasePage(pNewTrunk);
goto end_allocate_page;
}
memcpy(&pNewTrunk->aData[0], &pTrunk->aData[0], 4);
put4byte(&pNewTrunk->aData[4], k-1);
memcpy(&pNewTrunk->aData[8], &pTrunk->aData[12], (k-1)*4);
releasePage(pNewTrunk);
if( !pPrevTrunk ){
put4byte(&pPage1->aData[32], iNewTrunk);
}else{
rc = sqlite3PagerWrite(pPrevTrunk->pDbPage);
if( rc ){
goto end_allocate_page;
}
put4byte(&pPrevTrunk->aData[0], iNewTrunk);
}
}
pTrunk = 0;
TRACE(("ALLOCATE: %d trunk - %d free pages left\n", *pPgno, n-1));
#endif
}else{
int closest;
Pgno iPage;
unsigned char *aData = pTrunk->aData;
rc = sqlite3PagerWrite(pTrunk->pDbPage);
if( rc ){
goto end_allocate_page;
}
if( nearby>0 ){
int i, dist;
closest = 0;
dist = get4byte(&aData[8]) - nearby;
if( dist<0 ) dist = -dist;
for(i=1; i<k; i++){
int d2 = get4byte(&aData[8+i*4]) - nearby;
if( d2<0 ) d2 = -d2;
if( d2<dist ){
closest = i;
dist = d2;
}
}
}else{
closest = 0;
}
iPage = get4byte(&aData[8+closest*4]);
if( !searchList || iPage==nearby ){
*pPgno = iPage;
if( *pPgno>sqlite3PagerPagecount(pBt->pPager) ){
return SQLITE_CORRUPT_BKPT;
}
TRACE(("ALLOCATE: %d was leaf %d of %d on trunk %d"
": %d more free pages\n",
*pPgno, closest+1, k, pTrunk->pgno, n-1));
if( closest<k-1 ){
memcpy(&aData[8+closest*4], &aData[4+k*4], 4);
}
put4byte(&aData[4], k-1);
rc = getPage(pBt, *pPgno, ppPage, 1);
if( rc==SQLITE_OK ){
sqlite3PagerDontRollback((*ppPage)->pDbPage);
rc = sqlite3PagerWrite((*ppPage)->pDbPage);
if( rc!=SQLITE_OK ){
releasePage(*ppPage);
}
}
searchList = 0;
}
}
releasePage(pPrevTrunk);
pPrevTrunk = 0;
}while( searchList );
}else{
*pPgno = sqlite3PagerPagecount(pBt->pPager) + 1;
#ifndef SQLITE_OMIT_AUTOVACUUM
if( pBt->autoVacuum && PTRMAP_ISPAGE(pBt, *pPgno) ){
TRACE(("ALLOCATE: %d from end of file (pointer-map page)\n", *pPgno));
assert( *pPgno!=PENDING_BYTE_PAGE(pBt) );
(*pPgno)++;
}
#endif
assert( *pPgno!=PENDING_BYTE_PAGE(pBt) );
rc = getPage(pBt, *pPgno, ppPage, 0);
if( rc ) return rc;
rc = sqlite3PagerWrite((*ppPage)->pDbPage);
if( rc!=SQLITE_OK ){
releasePage(*ppPage);
}
TRACE(("ALLOCATE: %d from end of file\n", *pPgno));
}
assert( *pPgno!=PENDING_BYTE_PAGE(pBt) );
end_allocate_page:
releasePage(pTrunk);
releasePage(pPrevTrunk);
return rc;
}
static int freePage(MemPage *pPage){
BtShared *pBt = pPage->pBt;
MemPage *pPage1 = pBt->pPage1;
int rc, n, k;
assert( pPage->pgno>1 );
pPage->isInit = 0;
releasePage(pPage->pParent);
pPage->pParent = 0;
rc = sqlite3PagerWrite(pPage1->pDbPage);
if( rc ) return rc;
n = get4byte(&pPage1->aData[36]);
put4byte(&pPage1->aData[36], n+1);
#ifdef SQLITE_SECURE_DELETE
rc = sqlite3PagerWrite(pPage->pDbPage);
if( rc ) return rc;
memset(pPage->aData, 0, pPage->pBt->pageSize);
#endif
#ifndef SQLITE_OMIT_AUTOVACUUM
if( pBt->autoVacuum ){
rc = ptrmapPut(pBt, pPage->pgno, PTRMAP_FREEPAGE, 0);
if( rc ) return rc;
}
#endif
if( n==0 ){
rc = sqlite3PagerWrite(pPage->pDbPage);
if( rc ) return rc;
memset(pPage->aData, 0, 8);
put4byte(&pPage1->aData[32], pPage->pgno);
TRACE(("FREE-PAGE: %d first\n", pPage->pgno));
}else{
MemPage *pTrunk;
rc = getPage(pBt, get4byte(&pPage1->aData[32]), &pTrunk, 0);
if( rc ) return rc;
k = get4byte(&pTrunk->aData[4]);
if( k>=pBt->usableSize/4 - 8 ){
rc = sqlite3PagerWrite(pPage->pDbPage);
if( rc ) return rc;
put4byte(pPage->aData, pTrunk->pgno);
put4byte(&pPage->aData[4], 0);
put4byte(&pPage1->aData[32], pPage->pgno);
TRACE(("FREE-PAGE: %d new trunk page replacing %d\n",
pPage->pgno, pTrunk->pgno));
}else{
rc = sqlite3PagerWrite(pTrunk->pDbPage);
if( rc==SQLITE_OK ){
put4byte(&pTrunk->aData[4], k+1);
put4byte(&pTrunk->aData[8+k*4], pPage->pgno);
#ifndef SQLITE_SECURE_DELETE
sqlite3PagerDontWrite(pPage->pDbPage);
#endif
}
TRACE(("FREE-PAGE: %d leaf on trunk page %d\n",pPage->pgno,pTrunk->pgno));
}
releasePage(pTrunk);
}
return rc;
}
static int clearCell(MemPage *pPage, unsigned char *pCell){
BtShared *pBt = pPage->pBt;
CellInfo info;
Pgno ovflPgno;
int rc;
int nOvfl;
int ovflPageSize;
parseCellPtr(pPage, pCell, &info);
if( info.iOverflow==0 ){
return SQLITE_OK;
}
ovflPgno = get4byte(&pCell[info.iOverflow]);
ovflPageSize = pBt->usableSize - 4;
nOvfl = (info.nPayload - info.nLocal + ovflPageSize - 1)/ovflPageSize;
assert( ovflPgno==0 || nOvfl>0 );
while( nOvfl-- ){
MemPage *pOvfl;
if( ovflPgno==0 || ovflPgno>sqlite3PagerPagecount(pBt->pPager) ){
return SQLITE_CORRUPT_BKPT;
}
rc = getPage(pBt, ovflPgno, &pOvfl, nOvfl==0);
if( rc ) return rc;
if( nOvfl ){
ovflPgno = get4byte(pOvfl->aData);
}
rc = freePage(pOvfl);
sqlite3PagerUnref(pOvfl->pDbPage);
if( rc ) return rc;
}
return SQLITE_OK;
}
static int fillInCell(
MemPage *pPage,
unsigned char *pCell,
const void *pKey, i64 nKey,
const void *pData,int nData,
int *pnSize
){
int nPayload;
const u8 *pSrc;
int nSrc, n, rc;
int spaceLeft;
MemPage *pOvfl = 0;
MemPage *pToRelease = 0;
unsigned char *pPrior;
unsigned char *pPayload;
BtShared *pBt = pPage->pBt;
Pgno pgnoOvfl = 0;
int nHeader;
CellInfo info;
nHeader = 0;
if( !pPage->leaf ){
nHeader += 4;
}
if( pPage->hasData ){
nHeader += putVarint(&pCell[nHeader], nData);
}else{
nData = 0;
}
nHeader += putVarint(&pCell[nHeader], *(u64*)&nKey);
parseCellPtr(pPage, pCell, &info);
assert( info.nHeader==nHeader );
assert( info.nKey==nKey );
assert( info.nData==nData );
nPayload = nData;
if( pPage->intKey ){
pSrc = pData;
nSrc = nData;
nData = 0;
}else{
nPayload += nKey;
pSrc = pKey;
nSrc = nKey;
}
*pnSize = info.nSize;
spaceLeft = info.nLocal;
pPayload = &pCell[nHeader];
pPrior = &pCell[info.iOverflow];
while( nPayload>0 ){
if( spaceLeft==0 ){
#ifndef SQLITE_OMIT_AUTOVACUUM
Pgno pgnoPtrmap = pgnoOvfl;
#endif
rc = allocateBtreePage(pBt, &pOvfl, &pgnoOvfl, pgnoOvfl, 0);
#ifndef SQLITE_OMIT_AUTOVACUUM
if( pBt->autoVacuum && pgnoPtrmap!=0 && rc==SQLITE_OK ){
rc = ptrmapPut(pBt, pgnoOvfl, PTRMAP_OVERFLOW2, pgnoPtrmap);
}
#endif
if( rc ){
releasePage(pToRelease);
return rc;
}
put4byte(pPrior, pgnoOvfl);
releasePage(pToRelease);
pToRelease = pOvfl;
pPrior = pOvfl->aData;
put4byte(pPrior, 0);
pPayload = &pOvfl->aData[4];
spaceLeft = pBt->usableSize - 4;
}
n = nPayload;
if( n>spaceLeft ) n = spaceLeft;
if( n>nSrc ) n = nSrc;
assert( pSrc );
memcpy(pPayload, pSrc, n);
nPayload -= n;
pPayload += n;
pSrc += n;
nSrc -= n;
spaceLeft -= n;
if( nSrc==0 ){
nSrc = nData;
pSrc = pData;
}
}
releasePage(pToRelease);
return SQLITE_OK;
}
static int reparentPage(BtShared *pBt, Pgno pgno, MemPage *pNewParent, int idx){
MemPage *pThis;
DbPage *pDbPage;
assert( pNewParent!=0 );
if( pgno==0 ) return SQLITE_OK;
assert( pBt->pPager!=0 );
pDbPage = sqlite3PagerLookup(pBt->pPager, pgno);
if( pDbPage ){
pThis = (MemPage *)sqlite3PagerGetExtra(pDbPage);
if( pThis->isInit ){
assert( pThis->aData==(sqlite3PagerGetData(pDbPage)) );
if( pThis->pParent!=pNewParent ){
if( pThis->pParent ) sqlite3PagerUnref(pThis->pParent->pDbPage);
pThis->pParent = pNewParent;
sqlite3PagerRef(pNewParent->pDbPage);
}
pThis->idxParent = idx;
}
sqlite3PagerUnref(pDbPage);
}
#ifndef SQLITE_OMIT_AUTOVACUUM
if( pBt->autoVacuum ){
return ptrmapPut(pBt, pgno, PTRMAP_BTREE, pNewParent->pgno);
}
#endif
return SQLITE_OK;
}
static int reparentChildPages(MemPage *pPage){
int i;
BtShared *pBt = pPage->pBt;
int rc = SQLITE_OK;
if( pPage->leaf ) return SQLITE_OK;
for(i=0; i<pPage->nCell; i++){
u8 *pCell = findCell(pPage, i);
if( !pPage->leaf ){
rc = reparentPage(pBt, get4byte(pCell), pPage, i);
if( rc!=SQLITE_OK ) return rc;
}
}
if( !pPage->leaf ){
rc = reparentPage(pBt, get4byte(&pPage->aData[pPage->hdrOffset+8]),
pPage, i);
pPage->idxShift = 0;
}
return rc;
}
static void dropCell(MemPage *pPage, int idx, int sz){
int i;
int pc;
u8 *data;
u8 *ptr;
assert( idx>=0 && idx<pPage->nCell );
assert( sz==cellSize(pPage, idx) );
assert( sqlite3PagerIswriteable(pPage->pDbPage) );
data = pPage->aData;
ptr = &data[pPage->cellOffset + 2*idx];
pc = get2byte(ptr);
assert( pc>10 && pc+sz<=pPage->pBt->usableSize );
freeSpace(pPage, pc, sz);
for(i=idx+1; i<pPage->nCell; i++, ptr+=2){
ptr[0] = ptr[2];
ptr[1] = ptr[3];
}
pPage->nCell--;
put2byte(&data[pPage->hdrOffset+3], pPage->nCell);
pPage->nFree += 2;
pPage->idxShift = 1;
}
static int insertCell(
MemPage *pPage,
int i,
u8 *pCell,
int sz,
u8 *pTemp,
u8 nSkip
){
int idx;
int j;
int top;
int end;
int ins;
int hdr;
int cellOffset;
u8 *data;
u8 *ptr;
assert( i>=0 && i<=pPage->nCell+pPage->nOverflow );
assert( sz==cellSizePtr(pPage, pCell) );
assert( sqlite3PagerIswriteable(pPage->pDbPage) );
if( pPage->nOverflow || sz+2>pPage->nFree ){
if( pTemp ){
memcpy(pTemp+nSkip, pCell+nSkip, sz-nSkip);
pCell = pTemp;
}
j = pPage->nOverflow++;
assert( j<sizeof(pPage->aOvfl)/sizeof(pPage->aOvfl[0]) );
pPage->aOvfl[j].pCell = pCell;
pPage->aOvfl[j].idx = i;
pPage->nFree = 0;
}else{
data = pPage->aData;
hdr = pPage->hdrOffset;
top = get2byte(&data[hdr+5]);
cellOffset = pPage->cellOffset;
end = cellOffset + 2*pPage->nCell + 2;
ins = cellOffset + 2*i;
if( end > top - sz ){
int rc = defragmentPage(pPage);
if( rc!=SQLITE_OK ) return rc;
top = get2byte(&data[hdr+5]);
assert( end + sz <= top );
}
idx = allocateSpace(pPage, sz);
assert( idx>0 );
assert( end <= get2byte(&data[hdr+5]) );
pPage->nCell++;
pPage->nFree -= 2;
memcpy(&data[idx+nSkip], pCell+nSkip, sz-nSkip);
for(j=end-2, ptr=&data[j]; j>ins; j-=2, ptr-=2){
ptr[0] = ptr[-2];
ptr[1] = ptr[-1];
}
put2byte(&data[ins], idx);
put2byte(&data[hdr+3], pPage->nCell);
pPage->idxShift = 1;
#ifndef SQLITE_OMIT_AUTOVACUUM
if( pPage->pBt->autoVacuum ){
CellInfo info;
parseCellPtr(pPage, pCell, &info);
assert( (info.nData+(pPage->intKey?0:info.nKey))==info.nPayload );
if( (info.nData+(pPage->intKey?0:info.nKey))>info.nLocal ){
Pgno pgnoOvfl = get4byte(&pCell[info.iOverflow]);
int rc = ptrmapPut(pPage->pBt, pgnoOvfl, PTRMAP_OVERFLOW1, pPage->pgno);
if( rc!=SQLITE_OK ) return rc;
}
}
#endif
}
return SQLITE_OK;
}
static void assemblePage(
MemPage *pPage,
int nCell,
u8 **apCell,
int *aSize
){
int i;
int totalSize;
int hdr;
int cellptr;
int cellbody;
u8 *data;
assert( pPage->nOverflow==0 );
totalSize = 0;
for(i=0; i<nCell; i++){
totalSize += aSize[i];
}
assert( totalSize+2*nCell<=pPage->nFree );
assert( pPage->nCell==0 );
cellptr = pPage->cellOffset;
data = pPage->aData;
hdr = pPage->hdrOffset;
put2byte(&data[hdr+3], nCell);
if( nCell ){
cellbody = allocateSpace(pPage, totalSize);
assert( cellbody>0 );
assert( pPage->nFree >= 2*nCell );
pPage->nFree -= 2*nCell;
for(i=0; i<nCell; i++){
put2byte(&data[cellptr], cellbody);
memcpy(&data[cellbody], apCell[i], aSize[i]);
cellptr += 2;
cellbody += aSize[i];
}
assert( cellbody==pPage->pBt->usableSize );
}
pPage->nCell = nCell;
}
#define NN 1
#define NB (NN*2+1)
static int balance(MemPage*, int);
#ifndef SQLITE_OMIT_QUICKBALANCE
static int balance_quick(MemPage *pPage, MemPage *pParent){
int rc;
MemPage *pNew;
Pgno pgnoNew;
u8 *pCell;
int szCell;
CellInfo info;
BtShared *pBt = pPage->pBt;
int parentIdx = pParent->nCell;
int parentSize;
u8 parentCell[64];
rc = allocateBtreePage(pBt, &pNew, &pgnoNew, 0, 0);
if( rc!=SQLITE_OK ){
return rc;
}
pCell = pPage->aOvfl[0].pCell;
szCell = cellSizePtr(pPage, pCell);
zeroPage(pNew, pPage->aData[0]);
assemblePage(pNew, 1, &pCell, &szCell);
pPage->nOverflow = 0;
pNew->pParent = pParent;
sqlite3PagerRef(pParent->pDbPage);
assert( pPage->nCell>0 );
parseCellPtr(pPage, findCell(pPage, pPage->nCell-1), &info);
rc = fillInCell(pParent, parentCell, 0, info.nKey, 0, 0, &parentSize);
if( rc!=SQLITE_OK ){
return rc;
}
assert( parentSize<64 );
rc = insertCell(pParent, parentIdx, parentCell, parentSize, 0, 4);
if( rc!=SQLITE_OK ){
return rc;
}
put4byte(findOverflowCell(pParent,parentIdx), pPage->pgno);
put4byte(&pParent->aData[pParent->hdrOffset+8], pgnoNew);
#ifndef SQLITE_OMIT_AUTOVACUUM
if( pBt->autoVacuum ){
rc = ptrmapPut(pBt, pgnoNew, PTRMAP_BTREE, pParent->pgno);
if( rc!=SQLITE_OK ){
return rc;
}
rc = ptrmapPutOvfl(pNew, 0);
if( rc!=SQLITE_OK ){
return rc;
}
}
#endif
releasePage(pNew);
return balance(pParent, 0);
}
#endif
#ifndef SQLITE_OMIT_AUTOVACUUM
#define ISAUTOVACUUM (pBt->autoVacuum)
#else
#define ISAUTOVACUUM 0
#endif
static int balance_nonroot(MemPage *pPage){
MemPage *pParent;
BtShared *pBt;
int nCell = 0;
int nMaxCells = 0;
int nOld;
int nNew;
int nDiv;
int i, j, k;
int idx;
int nxDiv;
int rc;
int leafCorrection;
int leafData;
int usableSpace;
int pageFlags;
int subtotal;
int iSpace = 0;
MemPage *apOld[NB];
Pgno pgnoOld[NB];
MemPage *apCopy[NB];
MemPage *apNew[NB+2];
Pgno pgnoNew[NB+2];
u8 *apDiv[NB];
int cntNew[NB+2];
int szNew[NB+2];
u8 **apCell = 0;
int *szCell;
u8 *aCopy[NB];
u8 *aSpace;
#ifndef SQLITE_OMIT_AUTOVACUUM
u8 *aFrom = 0;
#endif
assert( pPage->isInit );
assert( sqlite3PagerIswriteable(pPage->pDbPage) );
pBt = pPage->pBt;
pParent = pPage->pParent;
assert( pParent );
if( SQLITE_OK!=(rc = sqlite3PagerWrite(pParent->pDbPage)) ){
return rc;
}
TRACE(("BALANCE: begin page %d child of %d\n", pPage->pgno, pParent->pgno));
#ifndef SQLITE_OMIT_QUICKBALANCE
if( pPage->leaf &&
pPage->intKey &&
pPage->leafData &&
pPage->nOverflow==1 &&
pPage->aOvfl[0].idx==pPage->nCell &&
pPage->pParent->pgno!=1 &&
get4byte(&pParent->aData[pParent->hdrOffset+8])==pPage->pgno
){
return balance_quick(pPage, pParent);
}
#endif
if( pParent->idxShift ){
Pgno pgno;
pgno = pPage->pgno;
assert( pgno==sqlite3PagerPagenumber(pPage->pDbPage) );
for(idx=0; idx<pParent->nCell; idx++){
if( get4byte(findCell(pParent, idx))==pgno ){
break;
}
}
assert( idx<pParent->nCell
|| get4byte(&pParent->aData[pParent->hdrOffset+8])==pgno );
}else{
idx = pPage->idxParent;
}
nOld = nNew = 0;
sqlite3PagerRef(pParent->pDbPage);
nxDiv = idx - NN;
if( nxDiv + NB > pParent->nCell ){
nxDiv = pParent->nCell - NB + 1;
}
if( nxDiv<0 ){
nxDiv = 0;
}
nDiv = 0;
for(i=0, k=nxDiv; i<NB; i++, k++){
if( k<pParent->nCell ){
apDiv[i] = findCell(pParent, k);
nDiv++;
assert( !pParent->leaf );
pgnoOld[i] = get4byte(apDiv[i]);
}else if( k==pParent->nCell ){
pgnoOld[i] = get4byte(&pParent->aData[pParent->hdrOffset+8]);
}else{
break;
}
rc = getAndInitPage(pBt, pgnoOld[i], &apOld[i], pParent);
if( rc ) goto balance_cleanup;
apOld[i]->idxParent = k;
apCopy[i] = 0;
assert( i==nOld );
nOld++;
nMaxCells += 1+apOld[i]->nCell+apOld[i]->nOverflow;
}
nMaxCells = (nMaxCells + 1)&~1;
apCell = sqliteMallocRaw(
nMaxCells*sizeof(u8*)
+ nMaxCells*sizeof(int)
+ ROUND8(sizeof(MemPage))*NB
+ pBt->pageSize*(5+NB)
+ (ISAUTOVACUUM ? nMaxCells : 0)
);
if( apCell==0 ){
rc = SQLITE_NOMEM;
goto balance_cleanup;
}
szCell = (int*)&apCell[nMaxCells];
aCopy[0] = (u8*)&szCell[nMaxCells];
assert( ((aCopy[0] - (u8*)apCell) & 7)==0 );
for(i=1; i<NB; i++){
aCopy[i] = &aCopy[i-1][pBt->pageSize+ROUND8(sizeof(MemPage))];
assert( ((aCopy[i] - (u8*)apCell) & 7)==0 );
}
aSpace = &aCopy[NB-1][pBt->pageSize+ROUND8(sizeof(MemPage))];
assert( ((aSpace - (u8*)apCell) & 7)==0 );
#ifndef SQLITE_OMIT_AUTOVACUUM
if( pBt->autoVacuum ){
aFrom = &aSpace[5*pBt->pageSize];
}
#endif
for(i=0; i<nOld; i++){
MemPage *p = apCopy[i] = (MemPage*)&aCopy[i][pBt->pageSize];
p->aData = &((u8*)p)[-pBt->pageSize];
memcpy(p->aData, apOld[i]->aData, pBt->pageSize + sizeof(MemPage));
p->aData = &((u8*)p)[-pBt->pageSize];
}
nCell = 0;
leafCorrection = pPage->leaf*4;
leafData = pPage->leafData && pPage->leaf;
for(i=0; i<nOld; i++){
MemPage *pOld = apCopy[i];
int limit = pOld->nCell+pOld->nOverflow;
for(j=0; j<limit; j++){
assert( nCell<nMaxCells );
apCell[nCell] = findOverflowCell(pOld, j);
szCell[nCell] = cellSizePtr(pOld, apCell[nCell]);
#ifndef SQLITE_OMIT_AUTOVACUUM
if( pBt->autoVacuum ){
int a;
aFrom[nCell] = i;
for(a=0; a<pOld->nOverflow; a++){
if( pOld->aOvfl[a].pCell==apCell[nCell] ){
aFrom[nCell] = 0xFF;
break;
}
}
}
#endif
nCell++;
}
if( i<nOld-1 ){
int sz = cellSizePtr(pParent, apDiv[i]);
if( leafData ){
dropCell(pParent, nxDiv, sz);
}else{
u8 *pTemp;
assert( nCell<nMaxCells );
szCell[nCell] = sz;
pTemp = &aSpace[iSpace];
iSpace += sz;
assert( iSpace<=pBt->pageSize*5 );
memcpy(pTemp, apDiv[i], sz);
apCell[nCell] = pTemp+leafCorrection;
#ifndef SQLITE_OMIT_AUTOVACUUM
if( pBt->autoVacuum ){
aFrom[nCell] = 0xFF;
}
#endif
dropCell(pParent, nxDiv, sz);
szCell[nCell] -= leafCorrection;
assert( get4byte(pTemp)==pgnoOld[i] );
if( !pOld->leaf ){
assert( leafCorrection==0 );
memcpy(apCell[nCell], &pOld->aData[pOld->hdrOffset+8], 4);
}else{
assert( leafCorrection==4 );
}
nCell++;
}
}
}
usableSpace = pBt->usableSize - 12 + leafCorrection;
for(subtotal=k=i=0; i<nCell; i++){
assert( i<nMaxCells );
subtotal += szCell[i] + 2;
if( subtotal > usableSpace ){
szNew[k] = subtotal - szCell[i];
cntNew[k] = i;
if( leafData ){ i--; }
subtotal = 0;
k++;
}
}
szNew[k] = subtotal;
cntNew[k] = nCell;
k++;
for(i=k-1; i>0; i--){
int szRight = szNew[i];
int szLeft = szNew[i-1];
int r;
int d;
r = cntNew[i-1] - 1;
d = r + 1 - leafData;
assert( d<nMaxCells );
assert( r<nMaxCells );
while( szRight==0 || szRight+szCell[d]+2<=szLeft-(szCell[r]+2) ){
szRight += szCell[d] + 2;
szLeft -= szCell[r] + 2;
cntNew[i-1]--;
r = cntNew[i-1] - 1;
d = r + 1 - leafData;
}
szNew[i] = szRight;
szNew[i-1] = szLeft;
}
assert( cntNew[0]>0 || (pParent->pgno==1 && pParent->nCell==0) );
assert( pPage->pgno>1 );
pageFlags = pPage->aData[0];
for(i=0; i<k; i++){
MemPage *pNew;
if( i<nOld ){
pNew = apNew[i] = apOld[i];
pgnoNew[i] = pgnoOld[i];
apOld[i] = 0;
rc = sqlite3PagerWrite(pNew->pDbPage);
nNew++;
if( rc ) goto balance_cleanup;
}else{
assert( i>0 );
rc = allocateBtreePage(pBt, &pNew, &pgnoNew[i], pgnoNew[i-1], 0);
if( rc ) goto balance_cleanup;
apNew[i] = pNew;
nNew++;
}
zeroPage(pNew, pageFlags);
}
while( i<nOld ){
rc = freePage(apOld[i]);
if( rc ) goto balance_cleanup;
releasePage(apOld[i]);
apOld[i] = 0;
i++;
}
for(i=0; i<k-1; i++){
int minV = pgnoNew[i];
int minI = i;
for(j=i+1; j<k; j++){
if( pgnoNew[j]<(unsigned)minV ){
minI = j;
minV = pgnoNew[j];
}
}
if( minI>i ){
int t;
MemPage *pT;
t = pgnoNew[i];
pT = apNew[i];
pgnoNew[i] = pgnoNew[minI];
apNew[i] = apNew[minI];
pgnoNew[minI] = t;
apNew[minI] = pT;
}
}
TRACE(("BALANCE: old: %d %d %d new: %d(%d) %d(%d) %d(%d) %d(%d) %d(%d)\n",
pgnoOld[0],
nOld>=2 ? pgnoOld[1] : 0,
nOld>=3 ? pgnoOld[2] : 0,
pgnoNew[0], szNew[0],
nNew>=2 ? pgnoNew[1] : 0, nNew>=2 ? szNew[1] : 0,
nNew>=3 ? pgnoNew[2] : 0, nNew>=3 ? szNew[2] : 0,
nNew>=4 ? pgnoNew[3] : 0, nNew>=4 ? szNew[3] : 0,
nNew>=5 ? pgnoNew[4] : 0, nNew>=5 ? szNew[4] : 0));
j = 0;
for(i=0; i<nNew; i++){
MemPage *pNew = apNew[i];
assert( j<nMaxCells );
assert( pNew->pgno==pgnoNew[i] );
assemblePage(pNew, cntNew[i]-j, &apCell[j], &szCell[j]);
assert( pNew->nCell>0 || (nNew==1 && cntNew[0]==0) );
assert( pNew->nOverflow==0 );
#ifndef SQLITE_OMIT_AUTOVACUUM
if( pBt->autoVacuum ){
for(k=j; k<cntNew[i]; k++){
assert( k<nMaxCells );
if( aFrom[k]==0xFF || apCopy[aFrom[k]]->pgno!=pNew->pgno ){
rc = ptrmapPutOvfl(pNew, k-j);
if( rc!=SQLITE_OK ){
goto balance_cleanup;
}
}
}
}
#endif
j = cntNew[i];
if( i<nNew-1 && j<nCell ){
u8 *pCell;
u8 *pTemp;
int sz;
assert( j<nMaxCells );
pCell = apCell[j];
sz = szCell[j] + leafCorrection;
if( !pNew->leaf ){
memcpy(&pNew->aData[8], pCell, 4);
pTemp = 0;
}else if( leafData ){
CellInfo info;
j--;
parseCellPtr(pNew, apCell[j], &info);
pCell = &aSpace[iSpace];
fillInCell(pParent, pCell, 0, info.nKey, 0, 0, &sz);
iSpace += sz;
assert( iSpace<=pBt->pageSize*5 );
pTemp = 0;
}else{
pCell -= 4;
pTemp = &aSpace[iSpace];
iSpace += sz;
assert( iSpace<=pBt->pageSize*5 );
}
rc = insertCell(pParent, nxDiv, pCell, sz, pTemp, 4);
if( rc!=SQLITE_OK ) goto balance_cleanup;
put4byte(findOverflowCell(pParent,nxDiv), pNew->pgno);
#ifndef SQLITE_OMIT_AUTOVACUUM
if( pBt->autoVacuum && !leafData ){
rc = ptrmapPutOvfl(pParent, nxDiv);
if( rc!=SQLITE_OK ){
goto balance_cleanup;
}
}
#endif
j++;
nxDiv++;
}
}
assert( j==nCell );
assert( nOld>0 );
assert( nNew>0 );
if( (pageFlags & PTF_LEAF)==0 ){
memcpy(&apNew[nNew-1]->aData[8], &apCopy[nOld-1]->aData[8], 4);
}
if( nxDiv==pParent->nCell+pParent->nOverflow ){
put4byte(&pParent->aData[pParent->hdrOffset+8], pgnoNew[nNew-1]);
}else{
put4byte(findOverflowCell(pParent, nxDiv), pgnoNew[nNew-1]);
}
for(i=0; i<nNew; i++){
rc = reparentChildPages(apNew[i]);
if( rc!=SQLITE_OK ) goto balance_cleanup;
}
rc = reparentChildPages(pParent);
if( rc!=SQLITE_OK ) goto balance_cleanup;
assert( pParent->isInit );
rc = balance(pParent, 0);
balance_cleanup:
sqliteFree(apCell);
for(i=0; i<nOld; i++){
releasePage(apOld[i]);
}
for(i=0; i<nNew; i++){
releasePage(apNew[i]);
}
releasePage(pParent);
TRACE(("BALANCE: finished with %d: old=%d new=%d cells=%d\n",
pPage->pgno, nOld, nNew, nCell));
return rc;
}
static int balance_shallower(MemPage *pPage){
MemPage *pChild;
Pgno pgnoChild;
int rc = SQLITE_OK;
BtShared *pBt;
int mxCellPerPage;
u8 **apCell;
int *szCell;
assert( pPage->pParent==0 );
assert( pPage->nCell==0 );
pBt = pPage->pBt;
mxCellPerPage = MX_CELL(pBt);
apCell = sqliteMallocRaw( mxCellPerPage*(sizeof(u8*)+sizeof(int)) );
if( apCell==0 ) return SQLITE_NOMEM;
szCell = (int*)&apCell[mxCellPerPage];
if( pPage->leaf ){
TRACE(("BALANCE: empty table %d\n", pPage->pgno));
}else{
pgnoChild = get4byte(&pPage->aData[pPage->hdrOffset+8]);
assert( pgnoChild>0 );
assert( pgnoChild<=sqlite3PagerPagecount(pPage->pBt->pPager) );
rc = getPage(pPage->pBt, pgnoChild, &pChild, 0);
if( rc ) goto end_shallow_balance;
if( pPage->pgno==1 ){
rc = initPage(pChild, pPage);
if( rc ) goto end_shallow_balance;
assert( pChild->nOverflow==0 );
if( pChild->nFree>=100 ){
int i;
zeroPage(pPage, pChild->aData[0]);
for(i=0; i<pChild->nCell; i++){
apCell[i] = findCell(pChild,i);
szCell[i] = cellSizePtr(pChild, apCell[i]);
}
assemblePage(pPage, pChild->nCell, apCell, szCell);
put4byte(&pPage->aData[pPage->hdrOffset+8],
get4byte(&pChild->aData[pChild->hdrOffset+8]));
freePage(pChild);
TRACE(("BALANCE: child %d transfer to page 1\n", pChild->pgno));
}else{
TRACE(("BALANCE: child %d will not fit on page 1\n", pChild->pgno));
}
}else{
memcpy(pPage->aData, pChild->aData, pPage->pBt->usableSize);
pPage->isInit = 0;
pPage->pParent = 0;
rc = initPage(pPage, 0);
assert( rc==SQLITE_OK );
freePage(pChild);
TRACE(("BALANCE: transfer child %d into root %d\n",
pChild->pgno, pPage->pgno));
}
rc = reparentChildPages(pPage);
assert( pPage->nOverflow==0 );
#ifndef SQLITE_OMIT_AUTOVACUUM
if( pBt->autoVacuum ){
int i;
for(i=0; i<pPage->nCell; i++){
rc = ptrmapPutOvfl(pPage, i);
if( rc!=SQLITE_OK ){
goto end_shallow_balance;
}
}
}
#endif
if( rc!=SQLITE_OK ) goto end_shallow_balance;
releasePage(pChild);
}
end_shallow_balance:
sqliteFree(apCell);
return rc;
}
static int balance_deeper(MemPage *pPage){
int rc;
MemPage *pChild;
Pgno pgnoChild;
BtShared *pBt;
int usableSize;
u8 *data;
u8 *cdata;
int hdr;
int brk;
assert( pPage->pParent==0 );
assert( pPage->nOverflow>0 );
pBt = pPage->pBt;
rc = allocateBtreePage(pBt, &pChild, &pgnoChild, pPage->pgno, 0);
if( rc ) return rc;
assert( sqlite3PagerIswriteable(pChild->pDbPage) );
usableSize = pBt->usableSize;
data = pPage->aData;
hdr = pPage->hdrOffset;
brk = get2byte(&data[hdr+5]);
cdata = pChild->aData;
memcpy(cdata, &data[hdr], pPage->cellOffset+2*pPage->nCell-hdr);
memcpy(&cdata[brk], &data[brk], usableSize-brk);
assert( pChild->isInit==0 );
rc = initPage(pChild, pPage);
if( rc ) goto balancedeeper_out;
memcpy(pChild->aOvfl, pPage->aOvfl, pPage->nOverflow*sizeof(pPage->aOvfl[0]));
pChild->nOverflow = pPage->nOverflow;
if( pChild->nOverflow ){
pChild->nFree = 0;
}
assert( pChild->nCell==pPage->nCell );
zeroPage(pPage, pChild->aData[0] & ~PTF_LEAF);
put4byte(&pPage->aData[pPage->hdrOffset+8], pgnoChild);
TRACE(("BALANCE: copy root %d into %d\n", pPage->pgno, pChild->pgno));
#ifndef SQLITE_OMIT_AUTOVACUUM
if( pBt->autoVacuum ){
int i;
rc = ptrmapPut(pBt, pChild->pgno, PTRMAP_BTREE, pPage->pgno);
if( rc ) goto balancedeeper_out;
for(i=0; i<pChild->nCell; i++){
rc = ptrmapPutOvfl(pChild, i);
if( rc!=SQLITE_OK ){
return rc;
}
}
}
#endif
rc = balance_nonroot(pChild);
balancedeeper_out:
releasePage(pChild);
return rc;
}
static int balance(MemPage *pPage, int insert){
int rc = SQLITE_OK;
if( pPage->pParent==0 ){
if( pPage->nOverflow>0 ){
rc = balance_deeper(pPage);
}
if( rc==SQLITE_OK && pPage->nCell==0 ){
rc = balance_shallower(pPage);
}
}else{
if( pPage->nOverflow>0 ||
(!insert && pPage->nFree>pPage->pBt->usableSize*2/3) ){
rc = balance_nonroot(pPage);
}
}
return rc;
}
static int checkReadLocks(Btree *pBtree, Pgno pgnoRoot, BtCursor *pExclude){
BtCursor *p;
BtShared *pBt = pBtree->pBt;
sqlite3 *db = pBtree->pSqlite;
for(p=pBt->pCursor; p; p=p->pNext){
if( p==pExclude ) continue;
if( p->eState!=CURSOR_VALID ) continue;
if( p->pgnoRoot!=pgnoRoot ) continue;
if( p->wrFlag==0 ){
sqlite3 *dbOther = p->pBtree->pSqlite;
if( dbOther==0 ||
(dbOther!=db && (dbOther->flags & SQLITE_ReadUncommitted)==0) ){
return SQLITE_LOCKED;
}
}else if( p->pPage->pgno!=p->pgnoRoot ){
moveToRoot(p);
}
}
return SQLITE_OK;
}
int sqlite3BtreeInsert(
BtCursor *pCur,
const void *pKey, i64 nKey,
const void *pData, int nData,
int appendBias
){
int rc;
int loc;
int szNew;
MemPage *pPage;
BtShared *pBt = pCur->pBtree->pBt;
unsigned char *oldCell;
unsigned char *newCell = 0;
if( pBt->inTransaction!=TRANS_WRITE ){
return pBt->readOnly ? SQLITE_READONLY : SQLITE_ERROR;
}
assert( !pBt->readOnly );
if( !pCur->wrFlag ){
return SQLITE_PERM;
}
if( checkReadLocks(pCur->pBtree, pCur->pgnoRoot, pCur) ){
return SQLITE_LOCKED;
}
clearCursorPosition(pCur);
if(
SQLITE_OK!=(rc = saveAllCursors(pBt, pCur->pgnoRoot, pCur)) ||
SQLITE_OK!=(rc = sqlite3BtreeMoveto(pCur, pKey, nKey, appendBias, &loc))
){
return rc;
}
pPage = pCur->pPage;
assert( pPage->intKey || nKey>=0 );
assert( pPage->leaf || !pPage->leafData );
TRACE(("INSERT: table=%d nkey=%lld ndata=%d page=%d %s\n",
pCur->pgnoRoot, nKey, nData, pPage->pgno,
loc==0 ? "overwrite" : "new entry"));
assert( pPage->isInit );
rc = sqlite3PagerWrite(pPage->pDbPage);
if( rc ) return rc;
newCell = sqliteMallocRaw( MX_CELL_SIZE(pBt) );
if( newCell==0 ) return SQLITE_NOMEM;
rc = fillInCell(pPage, newCell, pKey, nKey, pData, nData, &szNew);
if( rc ) goto end_insert;
assert( szNew==cellSizePtr(pPage, newCell) );
assert( szNew<=MX_CELL_SIZE(pBt) );
if( loc==0 && CURSOR_VALID==pCur->eState ){
int szOld;
assert( pCur->idx>=0 && pCur->idx<pPage->nCell );
oldCell = findCell(pPage, pCur->idx);
if( !pPage->leaf ){
memcpy(newCell, oldCell, 4);
}
szOld = cellSizePtr(pPage, oldCell);
rc = clearCell(pPage, oldCell);
if( rc ) goto end_insert;
dropCell(pPage, pCur->idx, szOld);
}else if( loc<0 && pPage->nCell>0 ){
assert( pPage->leaf );
pCur->idx++;
pCur->info.nSize = 0;
}else{
assert( pPage->leaf );
}
rc = insertCell(pPage, pCur->idx, newCell, szNew, 0, 0);
if( rc!=SQLITE_OK ) goto end_insert;
rc = balance(pPage, 1);
if( rc==SQLITE_OK ){
moveToRoot(pCur);
}
end_insert:
sqliteFree(newCell);
return rc;
}
int sqlite3BtreeDelete(BtCursor *pCur){
MemPage *pPage = pCur->pPage;
unsigned char *pCell;
int rc;
Pgno pgnoChild = 0;
BtShared *pBt = pCur->pBtree->pBt;
assert( pPage->isInit );
if( pBt->inTransaction!=TRANS_WRITE ){
return pBt->readOnly ? SQLITE_READONLY : SQLITE_ERROR;
}
assert( !pBt->readOnly );
if( pCur->idx >= pPage->nCell ){
return SQLITE_ERROR;
}
if( !pCur->wrFlag ){
return SQLITE_PERM;
}
if( checkReadLocks(pCur->pBtree, pCur->pgnoRoot, pCur) ){
return SQLITE_LOCKED;
}
if(
(rc = restoreOrClearCursorPosition(pCur))!=0 ||
(rc = saveAllCursors(pBt, pCur->pgnoRoot, pCur))!=0 ||
(rc = sqlite3PagerWrite(pPage->pDbPage))!=0
){
return rc;
}
pCell = findCell(pPage, pCur->idx);
if( !pPage->leaf ){
pgnoChild = get4byte(pCell);
}
rc = clearCell(pPage, pCell);
if( rc ) return rc;
if( !pPage->leaf ){
BtCursor leafCur;
unsigned char *pNext;
int szNext;
int notUsed;
unsigned char *tempCell = 0;
assert( !pPage->leafData );
getTempCursor(pCur, &leafCur);
rc = sqlite3BtreeNext(&leafCur, ¬Used);
if( rc==SQLITE_OK ){
rc = sqlite3PagerWrite(leafCur.pPage->pDbPage);
}
if( rc==SQLITE_OK ){
TRACE(("DELETE: table=%d delete internal from %d replace from leaf %d\n",
pCur->pgnoRoot, pPage->pgno, leafCur.pPage->pgno));
dropCell(pPage, pCur->idx, cellSizePtr(pPage, pCell));
pNext = findCell(leafCur.pPage, leafCur.idx);
szNext = cellSizePtr(leafCur.pPage, pNext);
assert( MX_CELL_SIZE(pBt)>=szNext+4 );
tempCell = sqliteMallocRaw( MX_CELL_SIZE(pBt) );
if( tempCell==0 ){
rc = SQLITE_NOMEM;
}
}
if( rc==SQLITE_OK ){
rc = insertCell(pPage, pCur->idx, pNext-4, szNext+4, tempCell, 0);
}
if( rc==SQLITE_OK ){
put4byte(findOverflowCell(pPage, pCur->idx), pgnoChild);
rc = balance(pPage, 0);
}
if( rc==SQLITE_OK ){
dropCell(leafCur.pPage, leafCur.idx, szNext);
rc = balance(leafCur.pPage, 0);
}
sqliteFree(tempCell);
releaseTempCursor(&leafCur);
}else{
TRACE(("DELETE: table=%d delete from leaf %d\n",
pCur->pgnoRoot, pPage->pgno));
dropCell(pPage, pCur->idx, cellSizePtr(pPage, pCell));
rc = balance(pPage, 0);
}
if( rc==SQLITE_OK ){
moveToRoot(pCur);
}
return rc;
}
int sqlite3BtreeCreateTable(Btree *p, int *piTable, int flags){
BtShared *pBt = p->pBt;
MemPage *pRoot;
Pgno pgnoRoot;
int rc;
if( pBt->inTransaction!=TRANS_WRITE ){
return pBt->readOnly ? SQLITE_READONLY : SQLITE_ERROR;
}
assert( !pBt->readOnly );
if( pBt->pCursor ){
return SQLITE_LOCKED;
}
#ifdef SQLITE_OMIT_AUTOVACUUM
rc = allocateBtreePage(pBt, &pRoot, &pgnoRoot, 1, 0);
if( rc ) return rc;
#else
if( pBt->autoVacuum ){
Pgno pgnoMove;
MemPage *pPageMove;
rc = sqlite3BtreeGetMeta(p, 4, &pgnoRoot);
if( rc!=SQLITE_OK ) return rc;
pgnoRoot++;
if( pgnoRoot==PTRMAP_PAGENO(pBt, pgnoRoot) ||
pgnoRoot==PENDING_BYTE_PAGE(pBt) ){
pgnoRoot++;
}
assert( pgnoRoot>=3 );
rc = allocateBtreePage(pBt, &pPageMove, &pgnoMove, pgnoRoot, 1);
if( rc!=SQLITE_OK ){
return rc;
}
if( pgnoMove!=pgnoRoot ){
u8 eType;
Pgno iPtrPage;
releasePage(pPageMove);
rc = getPage(pBt, pgnoRoot, &pRoot, 0);
if( rc!=SQLITE_OK ){
return rc;
}
rc = ptrmapGet(pBt, pgnoRoot, &eType, &iPtrPage);
if( rc!=SQLITE_OK || eType==PTRMAP_ROOTPAGE || eType==PTRMAP_FREEPAGE ){
releasePage(pRoot);
return rc;
}
assert( eType!=PTRMAP_ROOTPAGE );
assert( eType!=PTRMAP_FREEPAGE );
rc = sqlite3PagerWrite(pRoot->pDbPage);
if( rc!=SQLITE_OK ){
releasePage(pRoot);
return rc;
}
rc = relocatePage(pBt, pRoot, eType, iPtrPage, pgnoMove);
releasePage(pRoot);
if( rc!=SQLITE_OK ){
return rc;
}
rc = getPage(pBt, pgnoRoot, &pRoot, 0);
if( rc!=SQLITE_OK ){
return rc;
}
rc = sqlite3PagerWrite(pRoot->pDbPage);
if( rc!=SQLITE_OK ){
releasePage(pRoot);
return rc;
}
}else{
pRoot = pPageMove;
}
rc = ptrmapPut(pBt, pgnoRoot, PTRMAP_ROOTPAGE, 0);
if( rc ){
releasePage(pRoot);
return rc;
}
rc = sqlite3BtreeUpdateMeta(p, 4, pgnoRoot);
if( rc ){
releasePage(pRoot);
return rc;
}
}else{
rc = allocateBtreePage(pBt, &pRoot, &pgnoRoot, 1, 0);
if( rc ) return rc;
}
#endif
assert( sqlite3PagerIswriteable(pRoot->pDbPage) );
zeroPage(pRoot, flags | PTF_LEAF);
sqlite3PagerUnref(pRoot->pDbPage);
*piTable = (int)pgnoRoot;
return SQLITE_OK;
}
static int clearDatabasePage(
BtShared *pBt,
Pgno pgno,
MemPage *pParent,
int freePageFlag
){
MemPage *pPage = 0;
int rc;
unsigned char *pCell;
int i;
if( pgno>sqlite3PagerPagecount(pBt->pPager) ){
return SQLITE_CORRUPT_BKPT;
}
rc = getAndInitPage(pBt, pgno, &pPage, pParent);
if( rc ) goto cleardatabasepage_out;
for(i=0; i<pPage->nCell; i++){
pCell = findCell(pPage, i);
if( !pPage->leaf ){
rc = clearDatabasePage(pBt, get4byte(pCell), pPage->pParent, 1);
if( rc ) goto cleardatabasepage_out;
}
rc = clearCell(pPage, pCell);
if( rc ) goto cleardatabasepage_out;
}
if( !pPage->leaf ){
rc = clearDatabasePage(pBt, get4byte(&pPage->aData[8]), pPage->pParent, 1);
if( rc ) goto cleardatabasepage_out;
}
if( freePageFlag ){
rc = freePage(pPage);
}else if( (rc = sqlite3PagerWrite(pPage->pDbPage))==0 ){
zeroPage(pPage, pPage->aData[0] | PTF_LEAF);
}
cleardatabasepage_out:
releasePage(pPage);
return rc;
}
int sqlite3BtreeClearTable(Btree *p, int iTable){
int rc;
BtShared *pBt = p->pBt;
if( p->inTrans!=TRANS_WRITE ){
return pBt->readOnly ? SQLITE_READONLY : SQLITE_ERROR;
}
rc = checkReadLocks(p, iTable, 0);
if( rc ){
return rc;
}
if( SQLITE_OK!=(rc = saveAllCursors(pBt, iTable, 0)) ){
return rc;
}
return clearDatabasePage(pBt, (Pgno)iTable, 0, 0);
}
int sqlite3BtreeDropTable(Btree *p, int iTable, int *piMoved){
int rc;
MemPage *pPage = 0;
BtShared *pBt = p->pBt;
if( p->inTrans!=TRANS_WRITE ){
return pBt->readOnly ? SQLITE_READONLY : SQLITE_ERROR;
}
if( pBt->pCursor ){
return SQLITE_LOCKED;
}
rc = getPage(pBt, (Pgno)iTable, &pPage, 0);
if( rc ) return rc;
rc = sqlite3BtreeClearTable(p, iTable);
if( rc ){
releasePage(pPage);
return rc;
}
*piMoved = 0;
if( iTable>1 ){
#ifdef SQLITE_OMIT_AUTOVACUUM
rc = freePage(pPage);
releasePage(pPage);
#else
if( pBt->autoVacuum ){
Pgno maxRootPgno;
rc = sqlite3BtreeGetMeta(p, 4, &maxRootPgno);
if( rc!=SQLITE_OK ){
releasePage(pPage);
return rc;
}
if( iTable==maxRootPgno ){
rc = freePage(pPage);
releasePage(pPage);
if( rc!=SQLITE_OK ){
return rc;
}
}else{
MemPage *pMove;
releasePage(pPage);
rc = getPage(pBt, maxRootPgno, &pMove, 0);
if( rc!=SQLITE_OK ){
return rc;
}
rc = relocatePage(pBt, pMove, PTRMAP_ROOTPAGE, 0, iTable);
releasePage(pMove);
if( rc!=SQLITE_OK ){
return rc;
}
rc = getPage(pBt, maxRootPgno, &pMove, 0);
if( rc!=SQLITE_OK ){
return rc;
}
rc = freePage(pMove);
releasePage(pMove);
if( rc!=SQLITE_OK ){
return rc;
}
*piMoved = maxRootPgno;
}
maxRootPgno--;
if( maxRootPgno==PENDING_BYTE_PAGE(pBt) ){
maxRootPgno--;
}
if( maxRootPgno==PTRMAP_PAGENO(pBt, maxRootPgno) ){
maxRootPgno--;
}
assert( maxRootPgno!=PENDING_BYTE_PAGE(pBt) );
rc = sqlite3BtreeUpdateMeta(p, 4, maxRootPgno);
}else{
rc = freePage(pPage);
releasePage(pPage);
}
#endif
}else{
zeroPage(pPage, PTF_INTKEY|PTF_LEAF );
releasePage(pPage);
}
return rc;
}
int sqlite3BtreeGetMeta(Btree *p, int idx, u32 *pMeta){
DbPage *pDbPage;
int rc;
unsigned char *pP1;
BtShared *pBt = p->pBt;
rc = queryTableLock(p, 1, READ_LOCK);
if( rc!=SQLITE_OK ){
return rc;
}
assert( idx>=0 && idx<=15 );
rc = sqlite3PagerGet(pBt->pPager, 1, &pDbPage);
if( rc ) return rc;
pP1 = (unsigned char *)sqlite3PagerGetData(pDbPage);
*pMeta = get4byte(&pP1[36 + idx*4]);
sqlite3PagerUnref(pDbPage);
#ifdef SQLITE_OMIT_AUTOVACUUM
if( idx==4 && *pMeta>0 ) pBt->readOnly = 1;
#endif
rc = lockTable(p, 1, READ_LOCK);
return rc;
}
int sqlite3BtreeUpdateMeta(Btree *p, int idx, u32 iMeta){
BtShared *pBt = p->pBt;
unsigned char *pP1;
int rc;
assert( idx>=1 && idx<=15 );
if( p->inTrans!=TRANS_WRITE ){
return pBt->readOnly ? SQLITE_READONLY : SQLITE_ERROR;
}
assert( pBt->pPage1!=0 );
pP1 = pBt->pPage1->aData;
rc = sqlite3PagerWrite(pBt->pPage1->pDbPage);
if( rc ) return rc;
put4byte(&pP1[36 + idx*4], iMeta);
return SQLITE_OK;
}
int sqlite3BtreeFlags(BtCursor *pCur){
MemPage *pPage = pCur->pPage;
return pPage ? pPage->aData[pPage->hdrOffset] : 0;
}
#ifdef SQLITE_DEBUG
static int btreePageDump(BtShared *pBt, int pgno, int recursive, MemPage *pParent){
int rc;
MemPage *pPage;
int i, j, c;
int nFree;
u16 idx;
int hdr;
int nCell;
int isInit;
unsigned char *data;
char range[20];
unsigned char payload[20];
rc = getPage(pBt, (Pgno)pgno, &pPage, 0);
isInit = pPage->isInit;
if( pPage->isInit==0 ){
initPage(pPage, pParent);
}
if( rc ){
return rc;
}
hdr = pPage->hdrOffset;
data = pPage->aData;
c = data[hdr];
pPage->intKey = (c & (PTF_INTKEY|PTF_LEAFDATA))!=0;
pPage->zeroData = (c & PTF_ZERODATA)!=0;
pPage->leafData = (c & PTF_LEAFDATA)!=0;
pPage->leaf = (c & PTF_LEAF)!=0;
pPage->hasData = !(pPage->zeroData || (!pPage->leaf && pPage->leafData));
nCell = get2byte(&data[hdr+3]);
sqlite3DebugPrintf("PAGE %d: flags=0x%02x frag=%d parent=%d\n", pgno,
data[hdr], data[hdr+7],
(pPage->isInit && pPage->pParent) ? pPage->pParent->pgno : 0);
assert( hdr == (pgno==1 ? 100 : 0) );
idx = hdr + 12 - pPage->leaf*4;
for(i=0; i<nCell; i++){
CellInfo info;
Pgno child;
unsigned char *pCell;
int sz;
int addr;
addr = get2byte(&data[idx + 2*i]);
pCell = &data[addr];
parseCellPtr(pPage, pCell, &info);
sz = info.nSize;
sprintf(range,"%d..%d", addr, addr+sz-1);
if( pPage->leaf ){
child = 0;
}else{
child = get4byte(pCell);
}
sz = info.nData;
if( !pPage->intKey ) sz += info.nKey;
if( sz>sizeof(payload)-1 ) sz = sizeof(payload)-1;
memcpy(payload, &pCell[info.nHeader], sz);
for(j=0; j<sz; j++){
if( payload[j]<0x20 || payload[j]>0x7f ) payload[j] = '.';
}
payload[sz] = 0;
sqlite3DebugPrintf(
"cell %2d: i=%-10s chld=%-4d nk=%-4lld nd=%-4d payload=%s\n",
i, range, child, info.nKey, info.nData, payload
);
}
if( !pPage->leaf ){
sqlite3DebugPrintf("right_child: %d\n", get4byte(&data[hdr+8]));
}
nFree = 0;
i = 0;
idx = get2byte(&data[hdr+1]);
while( idx>0 && idx<pPage->pBt->usableSize ){
int sz = get2byte(&data[idx+2]);
sprintf(range,"%d..%d", idx, idx+sz-1);
nFree += sz;
sqlite3DebugPrintf("freeblock %2d: i=%-10s size=%-4d total=%d\n",
i, range, sz, nFree);
idx = get2byte(&data[idx]);
i++;
}
if( idx!=0 ){
sqlite3DebugPrintf("ERROR: next freeblock index out of range: %d\n", idx);
}
if( recursive && !pPage->leaf ){
for(i=0; i<nCell; i++){
unsigned char *pCell = findCell(pPage, i);
btreePageDump(pBt, get4byte(pCell), 1, pPage);
idx = get2byte(pCell);
}
btreePageDump(pBt, get4byte(&data[hdr+8]), 1, pPage);
}
pPage->isInit = isInit;
sqlite3PagerUnref(pPage->pDbPage);
fflush(stdout);
return SQLITE_OK;
}
int sqlite3BtreePageDump(Btree *p, int pgno, int recursive){
return btreePageDump(p->pBt, pgno, recursive, 0);
}
#endif
#if defined(SQLITE_TEST) || defined(SQLITE_DEBUG)
int sqlite3BtreeCursorInfo(BtCursor *pCur, int *aResult, int upCnt){
int cnt, idx;
MemPage *pPage = pCur->pPage;
BtCursor tmpCur;
int rc = restoreOrClearCursorPosition(pCur);
if( rc!=SQLITE_OK ){
return rc;
}
assert( pPage->isInit );
getTempCursor(pCur, &tmpCur);
while( upCnt-- ){
moveToParent(&tmpCur);
}
pPage = tmpCur.pPage;
aResult[0] = sqlite3PagerPagenumber(pPage->pDbPage);
assert( aResult[0]==pPage->pgno );
aResult[1] = tmpCur.idx;
aResult[2] = pPage->nCell;
if( tmpCur.idx>=0 && tmpCur.idx<pPage->nCell ){
getCellInfo(&tmpCur);
aResult[3] = tmpCur.info.nSize;
aResult[6] = tmpCur.info.nData;
aResult[7] = tmpCur.info.nHeader;
aResult[8] = tmpCur.info.nLocal;
}else{
aResult[3] = 0;
aResult[6] = 0;
aResult[7] = 0;
aResult[8] = 0;
}
aResult[4] = pPage->nFree;
cnt = 0;
idx = get2byte(&pPage->aData[pPage->hdrOffset+1]);
while( idx>0 && idx<pPage->pBt->usableSize ){
cnt++;
idx = get2byte(&pPage->aData[idx]);
}
aResult[5] = cnt;
if( pPage->pParent==0 || isRootPage(pPage) ){
aResult[9] = 0;
}else{
aResult[9] = pPage->pParent->pgno;
}
if( tmpCur.info.iOverflow ){
aResult[10] = get4byte(&tmpCur.info.pCell[tmpCur.info.iOverflow]);
}else{
aResult[10] = 0;
}
releaseTempCursor(&tmpCur);
return SQLITE_OK;
}
#endif
Pager *sqlite3BtreePager(Btree *p){
return p->pBt->pPager;
}
typedef struct IntegrityCk IntegrityCk;
struct IntegrityCk {
BtShared *pBt;
Pager *pPager;
int nPage;
int *anRef;
int mxErr;
char *zErrMsg;
int nErr;
};
#ifndef SQLITE_OMIT_INTEGRITY_CHECK
static void checkAppendMsg(
IntegrityCk *pCheck,
char *zMsg1,
const char *zFormat,
...
){
va_list ap;
char *zMsg2;
if( !pCheck->mxErr ) return;
pCheck->mxErr--;
pCheck->nErr++;
va_start(ap, zFormat);
zMsg2 = sqlite3VMPrintf(zFormat, ap);
va_end(ap);
if( zMsg1==0 ) zMsg1 = "";
if( pCheck->zErrMsg ){
char *zOld = pCheck->zErrMsg;
pCheck->zErrMsg = 0;
sqlite3SetString(&pCheck->zErrMsg, zOld, "\n", zMsg1, zMsg2, (char*)0);
sqliteFree(zOld);
}else{
sqlite3SetString(&pCheck->zErrMsg, zMsg1, zMsg2, (char*)0);
}
sqliteFree(zMsg2);
}
#endif
#ifndef SQLITE_OMIT_INTEGRITY_CHECK
static int checkRef(IntegrityCk *pCheck, int iPage, char *zContext){
if( iPage==0 ) return 1;
if( iPage>pCheck->nPage || iPage<0 ){
checkAppendMsg(pCheck, zContext, "invalid page number %d", iPage);
return 1;
}
if( pCheck->anRef[iPage]==1 ){
checkAppendMsg(pCheck, zContext, "2nd reference to page %d", iPage);
return 1;
}
return (pCheck->anRef[iPage]++)>1;
}
#ifndef SQLITE_OMIT_AUTOVACUUM
static void checkPtrmap(
IntegrityCk *pCheck,
Pgno iChild,
u8 eType,
Pgno iParent,
char *zContext
){
int rc;
u8 ePtrmapType;
Pgno iPtrmapParent;
rc = ptrmapGet(pCheck->pBt, iChild, &ePtrmapType, &iPtrmapParent);
if( rc!=SQLITE_OK ){
checkAppendMsg(pCheck, zContext, "Failed to read ptrmap key=%d", iChild);
return;
}
if( ePtrmapType!=eType || iPtrmapParent!=iParent ){
checkAppendMsg(pCheck, zContext,
"Bad ptr map entry key=%d expected=(%d,%d) got=(%d,%d)",
iChild, eType, iParent, ePtrmapType, iPtrmapParent);
}
}
#endif
static void checkList(
IntegrityCk *pCheck,
int isFreeList,
int iPage,
int N,
char *zContext
){
int i;
int expected = N;
int iFirst = iPage;
while( N-- > 0 && pCheck->mxErr ){
DbPage *pOvflPage;
unsigned char *pOvflData;
if( iPage<1 ){
checkAppendMsg(pCheck, zContext,
"%d of %d pages missing from overflow list starting at %d",
N+1, expected, iFirst);
break;
}
if( checkRef(pCheck, iPage, zContext) ) break;
if( sqlite3PagerGet(pCheck->pPager, (Pgno)iPage, &pOvflPage) ){
checkAppendMsg(pCheck, zContext, "failed to get page %d", iPage);
break;
}
pOvflData = (unsigned char *)sqlite3PagerGetData(pOvflPage);
if( isFreeList ){
int n = get4byte(&pOvflData[4]);
#ifndef SQLITE_OMIT_AUTOVACUUM
if( pCheck->pBt->autoVacuum ){
checkPtrmap(pCheck, iPage, PTRMAP_FREEPAGE, 0, zContext);
}
#endif
if( n>pCheck->pBt->usableSize/4-8 ){
checkAppendMsg(pCheck, zContext,
"freelist leaf count too big on page %d", iPage);
N--;
}else{
for(i=0; i<n; i++){
Pgno iFreePage = get4byte(&pOvflData[8+i*4]);
#ifndef SQLITE_OMIT_AUTOVACUUM
if( pCheck->pBt->autoVacuum ){
checkPtrmap(pCheck, iFreePage, PTRMAP_FREEPAGE, 0, zContext);
}
#endif
checkRef(pCheck, iFreePage, zContext);
}
N -= n;
}
}
#ifndef SQLITE_OMIT_AUTOVACUUM
else{
if( pCheck->pBt->autoVacuum && N>0 ){
i = get4byte(pOvflData);
checkPtrmap(pCheck, i, PTRMAP_OVERFLOW2, iPage, zContext);
}
}
#endif
iPage = get4byte(pOvflData);
sqlite3PagerUnref(pOvflPage);
}
}
#endif
#ifndef SQLITE_OMIT_INTEGRITY_CHECK
static int checkTreePage(
IntegrityCk *pCheck,
int iPage,
MemPage *pParent,
char *zParentContext
){
MemPage *pPage;
int i, rc, depth, d2, pgno, cnt;
int hdr, cellStart;
int nCell;
u8 *data;
BtShared *pBt;
int usableSize;
char zContext[100];
char *hit;
sprintf(zContext, "Page %d: ", iPage);
pBt = pCheck->pBt;
usableSize = pBt->usableSize;
if( iPage==0 ) return 0;
if( checkRef(pCheck, iPage, zParentContext) ) return 0;
if( (rc = getPage(pBt, (Pgno)iPage, &pPage, 0))!=0 ){
checkAppendMsg(pCheck, zContext,
"unable to get the page. error code=%d", rc);
return 0;
}
if( (rc = initPage(pPage, pParent))!=0 ){
checkAppendMsg(pCheck, zContext, "initPage() returns error code %d", rc);
releasePage(pPage);
return 0;
}
depth = 0;
for(i=0; i<pPage->nCell && pCheck->mxErr; i++){
u8 *pCell;
int sz;
CellInfo info;
sprintf(zContext, "On tree page %d cell %d: ", iPage, i);
pCell = findCell(pPage,i);
parseCellPtr(pPage, pCell, &info);
sz = info.nData;
if( !pPage->intKey ) sz += info.nKey;
assert( sz==info.nPayload );
if( sz>info.nLocal ){
int nPage = (sz - info.nLocal + usableSize - 5)/(usableSize - 4);
Pgno pgnoOvfl = get4byte(&pCell[info.iOverflow]);
#ifndef SQLITE_OMIT_AUTOVACUUM
if( pBt->autoVacuum ){
checkPtrmap(pCheck, pgnoOvfl, PTRMAP_OVERFLOW1, iPage, zContext);
}
#endif
checkList(pCheck, 0, pgnoOvfl, nPage, zContext);
}
if( !pPage->leaf ){
pgno = get4byte(pCell);
#ifndef SQLITE_OMIT_AUTOVACUUM
if( pBt->autoVacuum ){
checkPtrmap(pCheck, pgno, PTRMAP_BTREE, iPage, zContext);
}
#endif
d2 = checkTreePage(pCheck,pgno,pPage,zContext);
if( i>0 && d2!=depth ){
checkAppendMsg(pCheck, zContext, "Child page depth differs");
}
depth = d2;
}
}
if( !pPage->leaf ){
pgno = get4byte(&pPage->aData[pPage->hdrOffset+8]);
sprintf(zContext, "On page %d at right child: ", iPage);
#ifndef SQLITE_OMIT_AUTOVACUUM
if( pBt->autoVacuum ){
checkPtrmap(pCheck, pgno, PTRMAP_BTREE, iPage, 0);
}
#endif
checkTreePage(pCheck, pgno, pPage, zContext);
}
data = pPage->aData;
hdr = pPage->hdrOffset;
hit = sqliteMalloc( usableSize );
if( hit ){
memset(hit, 1, get2byte(&data[hdr+5]));
nCell = get2byte(&data[hdr+3]);
cellStart = hdr + 12 - 4*pPage->leaf;
for(i=0; i<nCell; i++){
int pc = get2byte(&data[cellStart+i*2]);
int size = cellSizePtr(pPage, &data[pc]);
int j;
if( (pc+size-1)>=usableSize || pc<0 ){
checkAppendMsg(pCheck, 0,
"Corruption detected in cell %d on page %d",i,iPage,0);
}else{
for(j=pc+size-1; j>=pc; j--) hit[j]++;
}
}
for(cnt=0, i=get2byte(&data[hdr+1]); i>0 && i<usableSize && cnt<10000;
cnt++){
int size = get2byte(&data[i+2]);
int j;
if( (i+size-1)>=usableSize || i<0 ){
checkAppendMsg(pCheck, 0,
"Corruption detected in cell %d on page %d",i,iPage,0);
}else{
for(j=i+size-1; j>=i; j--) hit[j]++;
}
i = get2byte(&data[i]);
}
for(i=cnt=0; i<usableSize; i++){
if( hit[i]==0 ){
cnt++;
}else if( hit[i]>1 ){
checkAppendMsg(pCheck, 0,
"Multiple uses for byte %d of page %d", i, iPage);
break;
}
}
if( cnt!=data[hdr+7] ){
checkAppendMsg(pCheck, 0,
"Fragmented space is %d byte reported as %d on page %d",
cnt, data[hdr+7], iPage);
}
}
sqliteFree(hit);
releasePage(pPage);
return depth+1;
}
#endif
#ifndef SQLITE_OMIT_INTEGRITY_CHECK
char *sqlite3BtreeIntegrityCheck(
Btree *p,
int *aRoot,
int nRoot,
int mxErr,
int *pnErr
){
int i;
int nRef;
IntegrityCk sCheck;
BtShared *pBt = p->pBt;
nRef = sqlite3PagerRefcount(pBt->pPager);
if( lockBtreeWithRetry(p)!=SQLITE_OK ){
return sqliteStrDup("Unable to acquire a read lock on the database");
}
sCheck.pBt = pBt;
sCheck.pPager = pBt->pPager;
sCheck.nPage = sqlite3PagerPagecount(sCheck.pPager);
sCheck.mxErr = mxErr;
sCheck.nErr = 0;
*pnErr = 0;
if( sCheck.nPage==0 ){
unlockBtreeIfUnused(pBt);
return 0;
}
sCheck.anRef = sqliteMallocRaw( (sCheck.nPage+1)*sizeof(sCheck.anRef[0]) );
if( !sCheck.anRef ){
unlockBtreeIfUnused(pBt);
*pnErr = 1;
return sqlite3MPrintf("Unable to malloc %d bytes",
(sCheck.nPage+1)*sizeof(sCheck.anRef[0]));
}
for(i=0; i<=sCheck.nPage; i++){ sCheck.anRef[i] = 0; }
i = PENDING_BYTE_PAGE(pBt);
if( i<=sCheck.nPage ){
sCheck.anRef[i] = 1;
}
sCheck.zErrMsg = 0;
checkList(&sCheck, 1, get4byte(&pBt->pPage1->aData[32]),
get4byte(&pBt->pPage1->aData[36]), "Main freelist: ");
for(i=0; i<nRoot && sCheck.mxErr; i++){
if( aRoot[i]==0 ) continue;
#ifndef SQLITE_OMIT_AUTOVACUUM
if( pBt->autoVacuum && aRoot[i]>1 ){
checkPtrmap(&sCheck, aRoot[i], PTRMAP_ROOTPAGE, 0, 0);
}
#endif
checkTreePage(&sCheck, aRoot[i], 0, "List of tree roots: ");
}
for(i=1; i<=sCheck.nPage && sCheck.mxErr; i++){
#ifdef SQLITE_OMIT_AUTOVACUUM
if( sCheck.anRef[i]==0 ){
checkAppendMsg(&sCheck, 0, "Page %d is never used", i);
}
#else
if( sCheck.anRef[i]==0 &&
(PTRMAP_PAGENO(pBt, i)!=i || !pBt->autoVacuum) ){
checkAppendMsg(&sCheck, 0, "Page %d is never used", i);
}
if( sCheck.anRef[i]!=0 &&
(PTRMAP_PAGENO(pBt, i)==i && pBt->autoVacuum) ){
checkAppendMsg(&sCheck, 0, "Pointer map page %d is referenced", i);
}
#endif
}
unlockBtreeIfUnused(pBt);
if( nRef != sqlite3PagerRefcount(pBt->pPager) ){
checkAppendMsg(&sCheck, 0,
"Outstanding page count goes from %d to %d during this analysis",
nRef, sqlite3PagerRefcount(pBt->pPager)
);
}
sqliteFree(sCheck.anRef);
*pnErr = sCheck.nErr;
return sCheck.zErrMsg;
}
#endif
const char *sqlite3BtreeGetFilename(Btree *p){
assert( p->pBt->pPager!=0 );
return sqlite3PagerFilename(p->pBt->pPager);
}
const char *sqlite3BtreeGetDirname(Btree *p){
assert( p->pBt->pPager!=0 );
return sqlite3PagerDirname(p->pBt->pPager);
}
const char *sqlite3BtreeGetJournalname(Btree *p){
assert( p->pBt->pPager!=0 );
return sqlite3PagerJournalname(p->pBt->pPager);
}
#ifndef SQLITE_OMIT_VACUUM
int sqlite3BtreeCopyFile(Btree *pTo, Btree *pFrom){
int rc = SQLITE_OK;
Pgno i, nPage, nToPage, iSkip;
BtShared *pBtTo = pTo->pBt;
BtShared *pBtFrom = pFrom->pBt;
if( pTo->inTrans!=TRANS_WRITE || pFrom->inTrans!=TRANS_WRITE ){
return SQLITE_ERROR;
}
if( pBtTo->pCursor ) return SQLITE_BUSY;
nToPage = sqlite3PagerPagecount(pBtTo->pPager);
nPage = sqlite3PagerPagecount(pBtFrom->pPager);
iSkip = PENDING_BYTE_PAGE(pBtTo);
for(i=1; rc==SQLITE_OK && i<=nPage; i++){
DbPage *pDbPage;
if( i==iSkip ) continue;
rc = sqlite3PagerGet(pBtFrom->pPager, i, &pDbPage);
if( rc ) break;
rc = sqlite3PagerOverwrite(pBtTo->pPager, i, sqlite3PagerGetData(pDbPage));
sqlite3PagerUnref(pDbPage);
}
for(i=nPage+1; rc==SQLITE_OK && i<=nToPage; i++){
DbPage *pDbPage;
if( i==iSkip ) continue;
rc = sqlite3PagerGet(pBtTo->pPager, i, &pDbPage);
if( rc ) break;
rc = sqlite3PagerWrite(pDbPage);
sqlite3PagerDontWrite(pDbPage);
sqlite3PagerUnref(pDbPage);
}
if( !rc && nPage<nToPage ){
rc = sqlite3PagerTruncate(pBtTo->pPager, nPage);
}
if( rc ){
sqlite3BtreeRollback(pTo);
}
return rc;
}
#endif
int sqlite3BtreeIsInTrans(Btree *p){
return (p && (p->inTrans==TRANS_WRITE));
}
int sqlite3BtreeIsInStmt(Btree *p){
return (p->pBt && p->pBt->inStmt);
}
int sqlite3BtreeIsInReadTrans(Btree *p){
return (p && (p->inTrans!=TRANS_NONE));
}
void *sqlite3BtreeSchema(Btree *p, int nBytes, void(*xFree)(void *)){
BtShared *pBt = p->pBt;
if( !pBt->pSchema ){
pBt->pSchema = sqliteMalloc(nBytes);
pBt->xFreeSchema = xFree;
}
return pBt->pSchema;
}
int sqlite3BtreeSchemaLocked(Btree *p){
return (queryTableLock(p, MASTER_ROOT, READ_LOCK)!=SQLITE_OK);
}
#ifndef SQLITE_OMIT_SHARED_CACHE
int sqlite3BtreeLockTable(Btree *p, int iTab, u8 isWriteLock){
int rc = SQLITE_OK;
u8 lockType = (isWriteLock?WRITE_LOCK:READ_LOCK);
rc = queryTableLock(p, iTab, lockType);
if( rc==SQLITE_OK ){
rc = lockTable(p, iTab, lockType);
}
return rc;
}
#endif
#if defined(SQLITE_DEBUG) && defined(TCLSH)
#include <tcl.h>
int sqlite3_shared_cache_report(
void * clientData,
Tcl_Interp *interp,
int objc,
Tcl_Obj *CONST objv[]
){
#ifndef SQLITE_OMIT_SHARED_CACHE
const ThreadData *pTd = sqlite3ThreadDataReadOnly();
if( pTd->useSharedData ){
BtShared *pBt;
Tcl_Obj *pRet = Tcl_NewObj();
for(pBt=pTd->pBtree; pBt; pBt=pBt->pNext){
const char *zFile = sqlite3PagerFilename(pBt->pPager);
Tcl_ListObjAppendElement(interp, pRet, Tcl_NewStringObj(zFile, -1));
Tcl_ListObjAppendElement(interp, pRet, Tcl_NewIntObj(pBt->nRef));
}
Tcl_SetObjResult(interp, pRet);
}
#endif
return TCL_OK;
}
#endif