** May you share freely, never taking more than you give.
**
*************************************************************************
-** $Id: btree.c,v 1.118 2004/05/09 01:35:06 drh Exp $
+** $Id: btree.c,v 1.119 2004/05/09 11:51:39 drh Exp $
**
** This file implements a external (disk-based) database using BTrees.
** For a detailed discussion of BTrees, refer to
u8 leaf; /* True if leaf flag is set */
u8 zeroData; /* True if zero data flag is set */
u8 hdrOffset; /* 100 for page 1. 0 otherwise */
+ u8 needRelink; /* True if need to run relinkCellList() */
int idxParent; /* Index in pParent->aCell[] of this node */
int nFree; /* Number of free bytes on the page */
int nCell; /* Number of entries on this page */
return n + nPayload;
}
+/*
+** Do sanity checking on a page. Throw an exception if anything is
+** not right.
+**
+** This routine is used for internal error checking only. It is omitted
+** from most builds.
+*/
+#if defined(BTREE_DEBUG) && !defined(NDEBUG) && 0
+static void _pageIntegrity(MemPage *pPage){
+ int pageSize;
+ u8 *data;
+ int i, idx, c, pc, hdr, nFree;
+ u8 used[MX_PAGE_SIZE];
+
+ pageSize = pPage->pBt->pageSize;
+ assert( pPage->aData==&((unsigned char*)pPage)[-pageSize] );
+ hdr = pPage->hdrOffset;
+ assert( hdr==(pPage->pgno==1 ? 100 : 0) );
+ assert( pPage->pgno==sqlite3pager_pagenumber(pPage->aData) );
+ c = pPage->aData[hdr];
+ if( pPage->isInit ){
+ assert( pPage->leaf == ((c & PTF_LEAF)!=0) );
+ assert( pPage->zeroData == ((c & PTF_ZERODATA)!=0) );
+ assert( pPage->intKey == ((c & PTF_INTKEY)!=0) );
+ }
+ data = pPage->aData;
+ memset(used, 0, pageSize);
+ for(i=0; i<hdr+10-pPage->leaf*4; i++) used[i] = 1;
+ nFree = 0;
+ pc = get2byte(&data[hdr+1]);
+ while( pc ){
+ int size;
+ assert( pc>0 && pc<pageSize-4 );
+ size = get2byte(&data[pc+2]);
+ assert( pc+size<=pageSize );
+ nFree += size;
+ for(i=pc; i<pc+size; i++){
+ assert( used[i]==0 );
+ used[i] = 1;
+ }
+ pc = get2byte(&data[pc]);
+ }
+ assert( pPage->isInit==0 || pPage->nFree==nFree+data[hdr+5] );
+ idx = 0;
+ pc = get2byte(&data[hdr+3]);
+ while( pc ){
+ int size;
+ assert( pPage->isInit==0 || idx<pPage->nCell );
+ assert( pc>0 && pc<pageSize-4 );
+ assert( pPage->isInit==0 || pPage->aCell[idx]==&data[pc] );
+ size = cellSize(pPage, &data[pc]);
+ assert( pc+size<=pageSize );
+ for(i=pc; i<pc+size; i++){
+ assert( used[i]==0 );
+ used[i] = 1;
+ }
+ pc = get2byte(&data[pc]);
+ idx++;
+ }
+ assert( idx==pPage->nCell );
+ nFree = 0;
+ for(i=0; i<pageSize; i++){
+ assert( used[i]<=1 );
+ if( used[i]==0 ) nFree++;
+ }
+ assert( nFree==data[hdr+5] );
+}
+#define pageIntegrity(X) _pageIntegrity(X)
+#else
+# define pageIntegrity(X)
+#endif
+
/*
** Defragment the page given. All Cells are moved to the
** beginning of the page and all free space is collected
assert( sqlite3pager_iswriteable(pPage->aData) );
assert( pPage->pBt!=0 );
assert( pPage->pBt->pageSize <= MX_PAGE_SIZE );
+ assert( !pPage->needRelink );
+ assert( !pPage->isOverfull );
oldPage = pPage->aData;
hdr = pPage->hdrOffset;
addr = 3+hdr;
size = cellSize(pPage, &oldPage[pc]);
memcpy(&newPage[n], &oldPage[pc], size);
put2byte(&newPage[addr],n);
+ assert( pPage->aCell[i]==&oldPage[pc] );
pPage->aCell[i++] = &oldPage[n];
+ addr = n;
n += size;
- addr = pc;
pc = get2byte(&oldPage[pc]);
}
assert( i==pPage->nCell );
assert( pParent==0 || pParent->pBt==pPage->pBt );
assert( pPage->pgno==sqlite3pager_pagenumber(pPage->aData) );
assert( pPage->aData == &((unsigned char*)pPage)[-pPage->pBt->pageSize] );
- assert( pPage->isInit==0 || pPage->pParent==pParent );
- if( pPage->isInit ) return SQLITE_OK;
- assert( pPage->pParent==0 );
- pPage->pParent = pParent;
- if( pParent ){
+ assert( pPage->pParent==0 || pPage->pParent==pParent );
+ if( pPage->pParent==0 && pParent!=0 ){
+ pPage->pParent = pParent;
sqlite3pager_ref(pParent->aData);
}
+ if( pPage->isInit ) return SQLITE_OK;
pPage->nCell = pPage->nCellAlloc = 0;
assert( pPage->hdrOffset==(pPage->pgno==1 ? 100 : 0) );
hdr = pPage->hdrOffset;
pPage->zeroData = (c & PTF_ZERODATA)!=0;
pPage->leaf = (c & PTF_LEAF)!=0;
pPage->isOverfull = 0;
+ pPage->needRelink = 0;
pPage->idxShift = 0;
pageSize = pPage->pBt->pageSize;
}
pPage->isInit = 1;
+ pageIntegrity(pPage);
return SQLITE_OK;
}
int hdr = pPage->hdrOffset;
int first;
+ assert( sqlite3pager_pagenumber(data)==pPage->pgno );
+ assert( &data[pBt->pageSize] == (unsigned char*)pPage );
assert( sqlite3pager_iswriteable(data) );
memset(&data[hdr], 0, pBt->pageSize - hdr);
data[hdr] = flags;
pPage->leaf = (flags & PTF_LEAF)!=0;
pPage->zeroData = (flags & PTF_ZERODATA)!=0;
pPage->hdrOffset = hdr;
+ pPage->isOverfull = 0;
+ pPage->needRelink = 0;
+ pPage->idxShift = 0;
+ pPage->isInit = 1;
+ pageIntegrity(pPage);
}
/*
*/
static void pageDestructor(void *pData){
MemPage *pPage = (MemPage*)&((char*)pData)[SQLITE_PAGE_SIZE];
+ assert( pPage->isInit==0 || pPage->needRelink==0 );
if( pPage->pParent ){
MemPage *pParent = pPage->pParent;
pPage->pParent = 0;
BtCursor *pCur;
for(pCur=pBt->pCursor; pCur; pCur=pCur->pNext){
MemPage *pPage = pCur->pPage;
- if( pPage && !pPage->isInit ){
+ if( pPage /* && !pPage->isInit */ ){
+ pageIntegrity(pPage);
releasePage(pPage);
pCur->pPage = 0;
pCur->isValid = 0;
}
}
+#ifdef SQLITE_TEST
+/*
+** Print debugging information about all cursors to standard output.
+*/
+void sqlite3BtreeCursorList(Btree *pBt){
+ BtCursor *pCur;
+ for(pCur=pBt->pCursor; pCur; pCur=pCur->pNext){
+ MemPage *pPage = pCur->pPage;
+ char *zMode = pCur->wrFlag ? "rw" : "ro";
+ printf("CURSOR %08x rooted at %4d(%s) currently at %d.%d%s\n",
+ (int)pCur, pCur->pgnoRoot, zMode,
+ pPage ? pPage->pgno : 0, pCur->idx,
+ pCur->isValid ? "" : " eof"
+ );
+ }
+}
+#endif
+
/*
** Rollback the transaction in progress. All cursors will be
** invalided by this operation. Any attempt to use a cursor
*pSize = 0;
}else{
pPage = pCur->pPage;
+ pageIntegrity(pPage);
assert( pPage!=0 );
assert( pCur->idx>=0 && pCur->idx<pPage->nCell );
cell = pPage->aCell[pCur->idx];
assert( pCur->isValid );
pBt = pCur->pBt;
pPage = pCur->pPage;
+ pageIntegrity(pPage);
assert( pCur->idx>=0 && pCur->idx<pPage->nCell );
aPayload = pPage->aCell[pCur->idx];
aPayload += 2; /* Skip the next cell index */
assert( pCur->idx>=0 && pCur->idx<pCur->pPage->nCell );
pBt = pCur->pBt;
pPage = pCur->pPage;
+ pageIntegrity(pPage);
assert( pCur->idx>=0 && pCur->idx<pPage->nCell );
assert( pPage->intKey==0 );
aPayload = pPage->aCell[pCur->idx];
pPage = pCur->pPage;
assert( pPage!=0 );
assert( pPage->isInit );
+ pageIntegrity(pPage);
if( pPage->zeroData ){
*pSize = 0;
}else{
assert( pCur->isValid );
rc = getAndInitPage(pBt, newPgno, &pNewPage, pCur->pPage);
if( rc ) return rc;
+ pageIntegrity(pNewPage);
pNewPage->idxParent = pCur->idx;
pOldPage = pCur->pPage;
pOldPage->idxShift = 0;
*/
static int isRootPage(MemPage *pPage){
MemPage *pParent = pPage->pParent;
- assert( pParent==0 || pParent->isInit );
- if( pParent==0 || (pParent->pgno==1 && pParent->nCell==0) ) return 1;
+ if( pParent==0 ) return 1;
+ if( pParent->pgno>1 ) return 0;
+ if( get2byte(&pParent->aData[pParent->hdrOffset+3])==0 ) return 1;
return 0;
}
pPage = pCur->pPage;
assert( pPage!=0 );
assert( !isRootPage(pPage) );
+ pageIntegrity(pPage);
pParent = pPage->pParent;
assert( pParent!=0 );
+ pageIntegrity(pParent);
idxParent = pPage->idxParent;
sqlite3pager_ref(pParent->aData);
oldPgno = pPage->pgno;
return rc;
}
releasePage(pCur->pPage);
+ pageIntegrity(pRoot);
pCur->pPage = pRoot;
pCur->idx = 0;
if( pRoot->nCell==0 && !pRoot->leaf ){
int c = -1; /* pRes return if table is empty must be -1 */
lwr = 0;
upr = pPage->nCell-1;
+ pageIntegrity(pPage);
while( lwr<=upr ){
void *pCellKey;
u64 nCellKey;
if( n==0 ){
/* This is the first free page */
+ rc = sqlite3pager_write(pPage->aData);
+ if( rc ) return rc;
memset(pPage->aData, 0, 8);
put4byte(&pPage1->aData[32], pPage->pgno);
}else{
if( pgno==0 ) return;
assert( pBt->pPager!=0 );
aData = sqlite3pager_lookup(pBt->pPager, pgno);
- pThis = (MemPage*)&aData[pBt->pageSize];
- if( pThis && pThis->isInit ){
- if( pThis->pParent!=pNewParent ){
- if( pThis->pParent ) sqlite3pager_unref(pThis->pParent->aData);
- pThis->pParent = pNewParent;
- if( pNewParent ) sqlite3pager_ref(pNewParent->aData);
- }
- pThis->idxParent = idx;
+ if( aData ){
+ pThis = (MemPage*)&aData[pBt->pageSize];
+ if( pThis->isInit ){
+ if( pThis->pParent!=pNewParent ){
+ if( pThis->pParent ) sqlite3pager_unref(pThis->pParent->aData);
+ pThis->pParent = pNewParent;
+ if( pNewParent ) sqlite3pager_ref(pNewParent->aData);
+ }
+ pThis->idxParent = idx;
+ }
sqlite3pager_unref(aData);
}
}
**
** "sz" must be the number of bytes in the cell.
**
-** Do not bother maintaining the integrity of the linked list of Cells.
-** Only the pPage->aCell[] array is important. The relinkCellList()
-** routine will be called soon after this routine in order to rebuild
-** the linked list.
+** Try to maintain the integrity of the linked list of cells. But if
+** the cell being inserted does not fit on the page, this will not be
+** possible. If the linked list is not maintained, then just update
+** pPage->aCell[] and set the pPage->needRelink flag so that we will
+** know to rebuild the linked list later.
*/
static void dropCell(MemPage *pPage, int idx, int sz){
int j, pc;
+ u8 *data;
assert( idx>=0 && idx<pPage->nCell );
assert( sz==cellSize(pPage, pPage->aCell[idx]) );
assert( sqlite3pager_iswriteable(pPage->aData) );
assert( pPage->aCell[idx]>=pPage->aData );
assert( pPage->aCell[idx]<&pPage->aData[pPage->pBt->pageSize-sz] );
- pc = Addr(pPage->aCell[idx]) - Addr(pPage->aData);
+ data = pPage->aData;
+ pc = Addr(pPage->aCell[idx]) - Addr(data);
assert( pc>pPage->hdrOffset && pc+sz<=pPage->pBt->pageSize );
freeSpace(pPage, pc, sz);
for(j=idx; j<pPage->nCell-1; j++){
pPage->aCell[j] = pPage->aCell[j+1];
}
pPage->nCell--;
+ if( !pPage->isOverfull && !pPage->needRelink ){
+ u8 *pPrev;
+ if( idx==0 ){
+ pPrev = &data[pPage->hdrOffset+3];
+ }else{
+ pPrev = pPage->aCell[idx-1];
+ }
+ if( idx<pPage->nCell ){
+ pc = Addr(pPage->aCell[idx]) - Addr(data);
+ }else{
+ pc = 0;
+ }
+ put2byte(pPrev, pc);
+ pageIntegrity(pPage);
+ }else{
+ pPage->needRelink = 1;
+ }
pPage->idxShift = 1;
}
** will not fit, then just make pPage->aCell[i] point to the content
** and set pPage->isOverfull.
**
-** Do not bother maintaining the integrity of the linked list of Cells.
-** Only the pPage->aCell[] array is important. The relinkCellList()
-** routine will be called soon after this routine in order to rebuild
-** the linked list.
+** Try to maintain the integrity of the linked list of cells. But if
+** the cell being inserted does not fit on the page, this will not be
+** possible. If the linked list is not maintained, then just update
+** pPage->aCell[] and set the pPage->needRelink flag so that we will
+** know to rebuild the linked list later.
*/
static void insertCell(MemPage *pPage, int i, unsigned char *pCell, int sz){
int idx, j;
assert( i>=0 && i<=pPage->nCell );
assert( sz==cellSize(pPage, pCell) );
assert( sqlite3pager_iswriteable(pPage->aData) );
- idx = allocateSpace(pPage, sz);
+ idx = pPage->needRelink ? 0 : allocateSpace(pPage, sz);
resizeCellArray(pPage, pPage->nCell+1);
for(j=pPage->nCell; j>i; j--){
pPage->aCell[j] = pPage->aCell[j-1];
pPage->isOverfull = 1;
pPage->aCell[i] = pCell;
}else{
- memcpy(&pPage->aData[idx], pCell, sz);
- pPage->aCell[i] = &pPage->aData[idx];
+ u8 *data = pPage->aData;
+ memcpy(&data[idx], pCell, sz);
+ pPage->aCell[i] = &data[idx];
+ }
+ if( !pPage->isOverfull && !pPage->needRelink ){
+ u8 *pPrev;
+ int pc;
+ if( i==0 ){
+ pPrev = &pPage->aData[pPage->hdrOffset+3];
+ }else{
+ pPrev = pPage->aCell[i-1];
+ }
+ pc = get2byte(pPrev);
+ put2byte(pPrev, idx);
+ put2byte(pPage->aCell[i], pc);
+ pageIntegrity(pPage);
+ }else{
+ pPage->needRelink = 1;
}
pPage->idxShift = 1;
}
static void relinkCellList(MemPage *pPage){
int i, idxFrom;
assert( sqlite3pager_iswriteable(pPage->aData) );
+ if( !pPage->needRelink ) return;
idxFrom = pPage->hdrOffset+3;
for(i=0; i<pPage->nCell; i++){
int idx = Addr(pPage->aCell[i]) - Addr(pPage->aData);
idxFrom = idx;
}
put2byte(&pPage->aData[idxFrom], 0);
+ pPage->needRelink = 0;
}
/*
**
** Over this operation completes, the meta data for pFrom is zeroed.
*/
-static void copyPage(MemPage *pTo, MemPage *pFrom){
+static void movePage(MemPage *pTo, MemPage *pFrom){
uptr from, to;
int i;
int pageSize;
}
}
+/*
+** For debugging...
+*/
+#if 1
+# define TRACE(X) if( pager3_refinfo_enable ) printf X
+#else
+# define TRACE(X)
+#endif
+
/*
** The following parameters determine how many adjacent pages get involved
** in a balancing operation. NN is the number of neighbors on either side
int usableSpace; /* Bytes in pPage beyond the header */
int pageFlags; /* Value of pPage->aData[0] */
int subtotal; /* Subtotal of bytes in cells on one page */
+ MemPage *extraUnref = 0; /* Unref this page if not zero */
MemPage *apOld[NB]; /* pPage and up to two siblings */
Pgno pgnoOld[NB]; /* Page numbers for each page in apOld[] */
MemPage *apCopy[NB]; /* Private copies of apOld[] pages */
** it means this page is the root page and special rules apply.
*/
pParent = pPage->pParent;
+ TRACE(("BALANCE: begin page %d\n", pPage->pgno));
if( pParent==0 ){
Pgno pgnoChild;
MemPage *pChild;
if( pPage->leaf ){
/* The table is completely empty */
relinkCellList(pPage);
+ TRACE(("BALANCE: empty table\n"));
}else{
/* The root page is empty but has one child. Transfer the
** information from that one child into the root page if it
cellSize(pChild, pChild->aCell[i]));
}
freePage(pChild);
+ TRACE(("BALANCE: child %d transfer to page 1\n", pChild->pgno));
}else{
/* The child has more information that will fit on the root.
** The tree is already balanced. Do nothing. */
+ TRACE(("BALANCE: child %d will not fit on page 1\n", pChild->pgno));
}
}else{
memcpy(pPage, pChild, pBt->pageSize);
rc = initPage(pPage, 0);
assert( rc==SQLITE_OK );
freePage(pChild);
+ TRACE(("BALANCE: transfer child %d into root\n", pChild->pgno));
}
reparentChildPages(pPage);
releasePage(pChild);
/* It is OK for the root page to be less than half full.
*/
relinkCellList(pPage);
+ TRACE(("BALANCE: Root page is underfull but that is ok\n"));
return SQLITE_OK;
}
/*
rc = allocatePage(pBt, &pChild, &pgnoChild, pPage->pgno);
if( rc ) return rc;
assert( sqlite3pager_iswriteable(pChild->aData) );
- copyPage(pChild, pPage);
+ movePage(pChild, pPage);
assert( pChild->aData[0]==pPage->aData[pPage->hdrOffset] );
pChild->pParent = pPage;
- pChild->idxParent = 0;
sqlite3pager_ref(pPage->aData);
+ pChild->idxParent = 0;
pChild->isOverfull = 1;
zeroPage(pPage, pChild->aData[0] & ~PTF_LEAF);
put4byte(&pPage->aData[pPage->hdrOffset+6], pChild->pgno);
pParent = pPage;
pPage = pChild;
- initPage(pParent, 0);
+ extraUnref = pChild;
+ TRACE(("BALANCE: Copy root into %d and blance\n", pPage->pgno));
}
rc = sqlite3pager_write(pParent->aData);
if( rc ) return rc;
for(i=0; i<nOld; i++){
MemPage *p = apCopy[i] = (MemPage*)&aCopy[i+1][-sizeof(MemPage)];
p->aData = &((u8*)p)[-pBt->pageSize];
- copyPage(p, apOld[i]);
+ p->aCell = 0;
+ p->hdrOffset = 0;
+ movePage(p, apOld[i]);
}
/*
nCell++;
}
if( i<nOld-1 ){
- szCell[nCell] = cellSize(pParent, apDiv[i]) - leafCorrection;
- memcpy(aTemp[i], apDiv[i], szCell[nCell] + leafCorrection);
+ szCell[nCell] = cellSize(pParent, apDiv[i]);
+ memcpy(aTemp[i], apDiv[i], szCell[nCell]);
apCell[nCell] = &aTemp[i][leafCorrection];
dropCell(pParent, nxDiv, szCell[nCell]);
- assert( get4byte(&apCell[nCell][2])==pgnoOld[i] );
+ szCell[nCell] -= leafCorrection;
+ assert( get4byte(&aTemp[i][2])==pgnoOld[i] );
if( !pOld->leaf ){
assert( leafCorrection==0 );
/* The right pointer of the child page pOld becomes the left
assert( pPage->pgno>1 );
pageFlags = pPage->aData[0];
for(i=0; i<k; i++){
+ MemPage *pNew;
if( i<nOld ){
- apNew[i] = apOld[i];
+ pNew = apNew[i] = apOld[i];
pgnoNew[i] = pgnoOld[i];
apOld[i] = 0;
- sqlite3pager_write(apNew[i]->aData);
+ sqlite3pager_write(pNew->aData);
}else{
- rc = allocatePage(pBt, &apNew[i], &pgnoNew[i], pgnoNew[i-1]);
+ rc = allocatePage(pBt, &pNew, &pgnoNew[i], pgnoNew[i-1]);
if( rc ) goto balance_cleanup;
+ apNew[i] = pNew;
}
nNew++;
- zeroPage(apNew[i], pageFlags);
- apNew[i]->isInit = 1;
+ zeroPage(pNew, pageFlags);
}
/* Free any old pages that were not reused as new pages.
while( i<nOld ){
rc = freePage(apOld[i]);
if( rc ) goto balance_cleanup;
- sqlite3pager_unref(apOld[i]->aData);
+ releasePage(apOld[i]);
apOld[i] = 0;
i++;
}
/*
** balance the parent page.
*/
+ assert( pPage->isInit );
+ assert( pParent->isInit );
+ pageIntegrity(pPage);
rc = balance(pParent);
+
/*
** Cleanup before returning.
for(i=0; i<nOld; i++){
releasePage(apOld[i]);
if( apCopy[i] ){
- releasePage(apCopy[i]->pParent);
sqliteFree(apCopy[i]->aCell);
}
}
releasePage(apNew[i]);
}
releasePage(pParent);
+ releasePage(extraUnref);
+ TRACE(("BALANCE: Finished with %d\n", pPage->pgno));
return rc;
}
unsigned char *pNext;
int szNext;
int notUsed;
+ unsigned char tempbuf[4];
getTempCursor(pCur, &leafCur);
rc = sqlite3BtreeNext(&leafCur, ¬Used);
if( rc!=SQLITE_OK ){
dropCell(pPage, pCur->idx, cellSize(pPage, pCell));
pNext = leafCur.pPage->aCell[leafCur.idx];
szNext = cellSize(leafCur.pPage, pNext);
- insertCell(pPage, pCur->idx, &pNext[-4], szNext+4);
+ memcpy(tempbuf, &pNext[-2], 4);
put4byte(&pNext[-2], pgnoChild);
+ insertCell(pPage, pCur->idx, &pNext[-4], szNext+4);
rc = balance(pPage);
if( rc ) return rc;
+ memcpy(&pNext[-2], tempbuf, 4);
dropCell(leafCur.pPage, leafCur.idx, szNext);
rc = balance(leafCur.pPage);
releaseTempCursor(&leafCur);
if( pBt->readOnly ){
return SQLITE_READONLY;
}
- rc = allocatePage(pBt, &pRoot, &pgnoRoot, 0);
+ rc = allocatePage(pBt, &pRoot, &pgnoRoot, 1);
if( rc ) return rc;
assert( sqlite3pager_iswriteable(pRoot->aData) );
zeroPage(pRoot, flags | PTF_LEAF);
pPage->intKey = (c & PTF_INTKEY)!=0;
pPage->zeroData = (c & PTF_ZERODATA)!=0;
pPage->leaf = (c & PTF_LEAF)!=0;
- printf("PAGE %d: flags=0x%02x frag=%d\n", pgno,
- data[hdr], data[hdr+5]);
+ printf("PAGE %d: flags=0x%02x frag=%d parent=%d\n", pgno,
+ data[hdr], data[hdr+5],
+ (pPage->isInit && pPage->pParent) ? pPage->pParent->pgno : 0);
i = 0;
assert( hdr == (pgno==1 ? 100 : 0) );
idx = get2byte(&data[hdr+3]);
**
** This routine is used for testing and debugging only.
*/
-int sqlite3BtreeCursorDump(BtCursor *pCur, int *aResult){
+int sqlite3BtreeCursorInfo(BtCursor *pCur, int *aResult){
int cnt, idx;
MemPage *pPage = pCur->pPage;
+
+ pageIntegrity(pPage);
assert( pPage->isInit );
aResult[0] = sqlite3pager_pagenumber(pPage->aData);
assert( aResult[0]==pPage->pgno );
**
** 1. Make sure that cells and freeblocks do not overlap
** but combine to completely cover the page.
-** 2. Make sure cell keys are in order.
-** 3. Make sure no key is less than or equal to zLowerBound.
-** 4. Make sure no key is greater than or equal to zUpperBound.
+** NO 2. Make sure cell keys are in order.
+** NO 3. Make sure no key is less than or equal to zLowerBound.
+** NO 4. Make sure no key is greater than or equal to zUpperBound.
** 5. Check the integrity of overflow pages.
** 6. Recursively call checkTreePage on all children.
** 7. Verify that the depth of all children is the same.
int nUpper /* Number of characters in zUpperBound */
){
MemPage *pPage;
- int i, rc, depth, d2, pgno;
+ int i, rc, depth, d2, pgno, cnt;
+ int hdr;
+ u8 *data;
char *zKey1, *zKey2;
int nKey1, nKey2;
BtCursor cur;
Btree *pBt;
+ int maxLocal, pageSize;
char zMsg[100];
char zContext[100];
- char hit[SQLITE_USABLE_SIZE];
+ char hit[MX_PAGE_SIZE];
/* Check that the page exists
*/
cur.pBt = pBt = pCheck->pBt;
+ maxLocal = pBt->maxLocal;
+ pageSize = pBt->pageSize;
if( iPage==0 ) return 0;
if( checkRef(pCheck, iPage, zParentContext) ) return 0;
sprintf(zContext, "On tree page %d: ", iPage);
return 0;
}
-#if 0
-
/* Check out all the cells.
*/
depth = 0;
- if( zLowerBound ){
- zKey1 = sqliteMalloc( nLower+1 );
- memcpy(zKey1, zLowerBound, nLower);
- zKey1[nLower] = 0;
- }else{
- zKey1 = 0;
- }
- nKey1 = nLower;
cur.pPage = pPage;
for(i=0; i<pPage->nCell; i++){
- Cell *pCell = pPage->aCell[i];
- int sz;
+ u8 *pCell = pPage->aCell[i];
+ u64 nKey, nData;
+ int sz, nHeader;
/* Check payload overflow pages
*/
- nKey2 = NKEY(pBt, pCell->h);
- sz = nKey2 + NDATA(pBt, pCell->h);
- sprintf(zContext, "On page %d cell %d: ", iPage, i);
- if( sz>MX_LOCAL_PAYLOAD ){
- int nPage = (sz - MX_LOCAL_PAYLOAD + OVERFLOW_SIZE - 1)/OVERFLOW_SIZE;
- checkList(pCheck, 0, SWAB32(pBt, pCell->ovfl), nPage, zContext);
- }
-
- /* Check that keys are in the right order
- */
- cur.idx = i;
- zKey2 = sqliteMallocRaw( nKey2+1 );
- getPayload(&cur, 0, nKey2, zKey2);
- if( zKey1 && keyCompare(zKey1, nKey1, zKey2, nKey2)>=0 ){
- checkAppendMsg(pCheck, zContext, "Key is out of order");
+ parseCellHeader(pPage, pCell, &nData, &nKey, &nHeader);
+ sz = nData;
+ if( !pPage->intKey ) sz += nKey;
+ if( sz>maxLocal ){
+ int nPage = (sz - maxLocal + pageSize - 5)/(pageSize - 4);
+ checkList(pCheck, 0, get4byte(&pCell[nHeader+maxLocal]),nPage,zContext);
}
/* Check sanity of left child page.
*/
- pgno = SWAB32(pBt, pCell->h.leftChild);
- d2 = checkTreePage(pCheck, pgno, pPage, zContext, zKey1,nKey1,zKey2,nKey2);
- if( i>0 && d2!=depth ){
- checkAppendMsg(pCheck, zContext, "Child page depth differs");
- }
- depth = d2;
- sqliteFree(zKey1);
- zKey1 = zKey2;
- nKey1 = nKey2;
- }
- pgno = SWAB32(pBt, pPage->u.hdr.rightChild);
- sprintf(zContext, "On page %d at right child: ", iPage);
- checkTreePage(pCheck, pgno, pPage, zContext, zKey1,nKey1,zUpperBound,nUpper);
- sqliteFree(zKey1);
+ if( !pPage->leaf ){
+ pgno = get4byte(&pCell[2]);
+ d2 = checkTreePage(pCheck,pgno,pPage,zContext,0,0,0,0);
+ if( i>0 && d2!=depth ){
+ checkAppendMsg(pCheck, zContext, "Child page depth differs");
+ }
+ depth = d2;
+ }
+ }
+ if( !pPage->leaf ){
+ pgno = get4byte(&pPage->aData[pPage->hdrOffset+6]);
+ sprintf(zContext, "On page %d at right child: ", iPage);
+ checkTreePage(pCheck, pgno, pPage, zContext,0,0,0,0);
+ }
/* Check for complete coverage of the page
*/
- memset(hit, 0, sizeof(hit));
- memset(hit, 1, sizeof(PageHdr));
- for(i=SWAB16(pBt, pPage->u.hdr.firstCell); i>0 && i<SQLITE_USABLE_SIZE; ){
- Cell *pCell = (Cell*)&pPage->u.aDisk[i];
+ memset(hit, 0, pageSize);
+ memset(hit, 1, pPage->hdrOffset+10-4*(pPage->leaf));
+ data = pPage->aData;
+ hdr = pPage->hdrOffset;
+ for(cnt=0, i=get2byte(&data[hdr+3]); i>0 && i<pageSize && cnt<10000; cnt++){
+ int size = cellSize(pPage, &data[i]);
int j;
- for(j=i+cellSize(pBt, pCell)-1; j>=i; j--) hit[j]++;
- i = SWAB16(pBt, pCell->h.iNext);
+ for(j=i+size-1; j>=i; j--) hit[j]++;
+ i = get2byte(&data[i]);
}
- for(i=SWAB16(pBt,pPage->u.hdr.firstFree); i>0 && i<SQLITE_USABLE_SIZE; ){
- FreeBlk *pFBlk = (FreeBlk*)&pPage->u.aDisk[i];
+ for(cnt=0, i=get2byte(&data[hdr+1]); i>0 && i<pageSize && cnt<10000; cnt++){
+ int size = get2byte(&data[i+2]);
int j;
- for(j=i+SWAB16(pBt,pFBlk->iSize)-1; j>=i; j--) hit[j]++;
- i = SWAB16(pBt,pFBlk->iNext);
+ for(j=i+size-1; j>=i; j--) hit[j]++;
+ i = get2byte(&data[i]);
}
- for(i=0; i<SQLITE_USABLE_SIZE; i++){
+ for(i=cnt=0; i<pageSize; i++){
if( hit[i]==0 ){
- sprintf(zMsg, "Unused space at byte %d of page %d", i, iPage);
- checkAppendMsg(pCheck, zMsg, 0);
- break;
+ cnt++;
}else if( hit[i]>1 ){
sprintf(zMsg, "Multiple uses for byte %d of page %d", i, iPage);
checkAppendMsg(pCheck, zMsg, 0);
break;
}
}
-
-#endif
+ if( cnt!=data[hdr+5] ){
+ sprintf(zMsg, "Fragmented space is %d byte reported as %d on page %d",
+ cnt, data[hdr+5], iPage);
+ checkAppendMsg(pCheck, zMsg, 0);
+ }
releasePage(pPage);
- return depth;
+ return depth+1;
}
/*
return 0;
}
sCheck.anRef = sqliteMallocRaw( (sCheck.nPage+1)*sizeof(sCheck.anRef[0]) );
- sCheck.anRef[1] = 1;
- for(i=2; i<=sCheck.nPage; i++){ sCheck.anRef[i] = 0; }
+ for(i=0; i<=sCheck.nPage; i++){ sCheck.anRef[i] = 0; }
sCheck.zErrMsg = 0;
/* Check the integrity of the freelist
projects / thirdparty / sqlite.git / commitdiff
