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-rw-r--r--ext/recover/dbdata.c200
1 files changed, 124 insertions, 76 deletions
diff --git a/ext/recover/dbdata.c b/ext/recover/dbdata.c
index ca63710..109aeef 100644
--- a/ext/recover/dbdata.c
+++ b/ext/recover/dbdata.c
@@ -88,6 +88,15 @@ typedef unsigned int u32;
typedef struct DbdataTable DbdataTable;
typedef struct DbdataCursor DbdataCursor;
+typedef struct DbdataBuffer DbdataBuffer;
+
+/*
+** Buffer type.
+*/
+struct DbdataBuffer {
+ u8 *aBuf;
+ sqlite3_int64 nBuf;
+};
/* Cursor object */
struct DbdataCursor {
@@ -104,7 +113,7 @@ struct DbdataCursor {
sqlite3_int64 iRowid;
/* Only for the sqlite_dbdata table */
- u8 *pRec; /* Buffer containing current record */
+ DbdataBuffer rec;
sqlite3_int64 nRec; /* Size of pRec[] in bytes */
sqlite3_int64 nHdr; /* Size of header in bytes */
int iField; /* Current field number */
@@ -150,6 +159,31 @@ struct DbdataTable {
")"
/*
+** Ensure the buffer passed as the first argument is at least nMin bytes
+** in size. If an error occurs while attempting to resize the buffer,
+** SQLITE_NOMEM is returned. Otherwise, SQLITE_OK.
+*/
+static int dbdataBufferSize(DbdataBuffer *pBuf, sqlite3_int64 nMin){
+ if( nMin>pBuf->nBuf ){
+ sqlite3_int64 nNew = nMin+16384;
+ u8 *aNew = (u8*)sqlite3_realloc64(pBuf->aBuf, nNew);
+
+ if( aNew==0 ) return SQLITE_NOMEM;
+ pBuf->aBuf = aNew;
+ pBuf->nBuf = nNew;
+ }
+ return SQLITE_OK;
+}
+
+/*
+** Release the allocation managed by buffer pBuf.
+*/
+static void dbdataBufferFree(DbdataBuffer *pBuf){
+ sqlite3_free(pBuf->aBuf);
+ memset(pBuf, 0, sizeof(*pBuf));
+}
+
+/*
** Connect to an sqlite_dbdata (pAux==0) or sqlite_dbptr (pAux!=0) virtual
** table.
*/
@@ -289,9 +323,9 @@ static void dbdataResetCursor(DbdataCursor *pCsr){
pCsr->iField = 0;
pCsr->bOnePage = 0;
sqlite3_free(pCsr->aPage);
- sqlite3_free(pCsr->pRec);
- pCsr->pRec = 0;
+ dbdataBufferFree(&pCsr->rec);
pCsr->aPage = 0;
+ pCsr->nRec = 0;
}
/*
@@ -433,63 +467,75 @@ static void dbdataValue(
u8 *pData,
sqlite3_int64 nData
){
- if( eType>=0 && dbdataValueBytes(eType)<=nData ){
- switch( eType ){
- case 0:
- case 10:
- case 11:
- sqlite3_result_null(pCtx);
- break;
-
- case 8:
- sqlite3_result_int(pCtx, 0);
- break;
- case 9:
- sqlite3_result_int(pCtx, 1);
- break;
-
- case 1: case 2: case 3: case 4: case 5: case 6: case 7: {
- sqlite3_uint64 v = (signed char)pData[0];
- pData++;
- switch( eType ){
- case 7:
- case 6: v = (v<<16) + (pData[0]<<8) + pData[1]; pData += 2;
- case 5: v = (v<<16) + (pData[0]<<8) + pData[1]; pData += 2;
- case 4: v = (v<<8) + pData[0]; pData++;
- case 3: v = (v<<8) + pData[0]; pData++;
- case 2: v = (v<<8) + pData[0]; pData++;
- }
-
- if( eType==7 ){
- double r;
- memcpy(&r, &v, sizeof(r));
- sqlite3_result_double(pCtx, r);
- }else{
- sqlite3_result_int64(pCtx, (sqlite3_int64)v);
+ if( eType>=0 ){
+ if( dbdataValueBytes(eType)<=nData ){
+ switch( eType ){
+ case 0:
+ case 10:
+ case 11:
+ sqlite3_result_null(pCtx);
+ break;
+
+ case 8:
+ sqlite3_result_int(pCtx, 0);
+ break;
+ case 9:
+ sqlite3_result_int(pCtx, 1);
+ break;
+
+ case 1: case 2: case 3: case 4: case 5: case 6: case 7: {
+ sqlite3_uint64 v = (signed char)pData[0];
+ pData++;
+ switch( eType ){
+ case 7:
+ case 6: v = (v<<16) + (pData[0]<<8) + pData[1]; pData += 2;
+ case 5: v = (v<<16) + (pData[0]<<8) + pData[1]; pData += 2;
+ case 4: v = (v<<8) + pData[0]; pData++;
+ case 3: v = (v<<8) + pData[0]; pData++;
+ case 2: v = (v<<8) + pData[0]; pData++;
+ }
+
+ if( eType==7 ){
+ double r;
+ memcpy(&r, &v, sizeof(r));
+ sqlite3_result_double(pCtx, r);
+ }else{
+ sqlite3_result_int64(pCtx, (sqlite3_int64)v);
+ }
+ break;
}
- break;
- }
-
- default: {
- int n = ((eType-12) / 2);
- if( eType % 2 ){
- switch( enc ){
-#ifndef SQLITE_OMIT_UTF16
- case SQLITE_UTF16BE:
- sqlite3_result_text16be(pCtx, (void*)pData, n, SQLITE_TRANSIENT);
- break;
- case SQLITE_UTF16LE:
- sqlite3_result_text16le(pCtx, (void*)pData, n, SQLITE_TRANSIENT);
- break;
-#endif
- default:
- sqlite3_result_text(pCtx, (char*)pData, n, SQLITE_TRANSIENT);
- break;
+
+ default: {
+ int n = ((eType-12) / 2);
+ if( eType % 2 ){
+ switch( enc ){
+ #ifndef SQLITE_OMIT_UTF16
+ case SQLITE_UTF16BE:
+ sqlite3_result_text16be(pCtx, (void*)pData, n, SQLITE_TRANSIENT);
+ break;
+ case SQLITE_UTF16LE:
+ sqlite3_result_text16le(pCtx, (void*)pData, n, SQLITE_TRANSIENT);
+ break;
+ #endif
+ default:
+ sqlite3_result_text(pCtx, (char*)pData, n, SQLITE_TRANSIENT);
+ break;
+ }
+ }else{
+ sqlite3_result_blob(pCtx, pData, n, SQLITE_TRANSIENT);
}
- }else{
- sqlite3_result_blob(pCtx, pData, n, SQLITE_TRANSIENT);
}
}
+ }else{
+ if( eType==7 ){
+ sqlite3_result_double(pCtx, 0.0);
+ }else if( eType<7 ){
+ sqlite3_result_int(pCtx, 0);
+ }else if( eType%2 ){
+ sqlite3_result_text(pCtx, "", 0, SQLITE_STATIC);
+ }else{
+ sqlite3_result_blob(pCtx, "", 0, SQLITE_STATIC);
+ }
}
}
}
@@ -551,7 +597,8 @@ static int dbdataNext(sqlite3_vtab_cursor *pCursor){
}
}else{
/* If there is no record loaded, load it now. */
- if( pCsr->pRec==0 ){
+ assert( pCsr->rec.aBuf!=0 || pCsr->nRec==0 );
+ if( pCsr->nRec==0 ){
int bHasRowid = 0;
int nPointer = 0;
sqlite3_int64 nPayload = 0;
@@ -595,6 +642,7 @@ static int dbdataNext(sqlite3_vtab_cursor *pCursor){
}else{
iOff += dbdataGetVarintU32(&pCsr->aPage[iOff], &nPayload);
if( nPayload>0x7fffff00 ) nPayload &= 0x3fff;
+ if( nPayload==0 ) nPayload = 1;
}
/* If this is a leaf intkey cell, load the rowid */
@@ -629,13 +677,12 @@ static int dbdataNext(sqlite3_vtab_cursor *pCursor){
/* Allocate space for payload. And a bit more to catch small buffer
** overruns caused by attempting to read a varint or similar from
** near the end of a corrupt record. */
- pCsr->pRec = (u8*)sqlite3_malloc64(nPayload+DBDATA_PADDING_BYTES);
- if( pCsr->pRec==0 ) return SQLITE_NOMEM;
- memset(pCsr->pRec, 0, nPayload+DBDATA_PADDING_BYTES);
- pCsr->nRec = nPayload;
+ rc = dbdataBufferSize(&pCsr->rec, nPayload+DBDATA_PADDING_BYTES);
+ if( rc!=SQLITE_OK ) return rc;
+ assert( nPayload!=0 );
/* Load the nLocal bytes of payload */
- memcpy(pCsr->pRec, &pCsr->aPage[iOff], nLocal);
+ memcpy(pCsr->rec.aBuf, &pCsr->aPage[iOff], nLocal);
iOff += nLocal;
/* Load content from overflow pages */
@@ -653,19 +700,22 @@ static int dbdataNext(sqlite3_vtab_cursor *pCursor){
nCopy = U-4;
if( nCopy>nRem ) nCopy = nRem;
- memcpy(&pCsr->pRec[nPayload-nRem], &aOvfl[4], nCopy);
+ memcpy(&pCsr->rec.aBuf[nPayload-nRem], &aOvfl[4], nCopy);
nRem -= nCopy;
pgnoOvfl = get_uint32(aOvfl);
sqlite3_free(aOvfl);
}
+ nPayload -= nRem;
}
+ memset(&pCsr->rec.aBuf[nPayload], 0, DBDATA_PADDING_BYTES);
+ pCsr->nRec = nPayload;
- iHdr = dbdataGetVarintU32(pCsr->pRec, &nHdr);
+ iHdr = dbdataGetVarintU32(pCsr->rec.aBuf, &nHdr);
if( nHdr>nPayload ) nHdr = 0;
pCsr->nHdr = nHdr;
- pCsr->pHdrPtr = &pCsr->pRec[iHdr];
- pCsr->pPtr = &pCsr->pRec[pCsr->nHdr];
+ pCsr->pHdrPtr = &pCsr->rec.aBuf[iHdr];
+ pCsr->pPtr = &pCsr->rec.aBuf[pCsr->nHdr];
pCsr->iField = (bHasRowid ? -1 : 0);
}
}
@@ -673,7 +723,7 @@ static int dbdataNext(sqlite3_vtab_cursor *pCursor){
pCsr->iField++;
if( pCsr->iField>0 ){
sqlite3_int64 iType;
- if( pCsr->pHdrPtr>=&pCsr->pRec[pCsr->nRec]
+ if( pCsr->pHdrPtr>=&pCsr->rec.aBuf[pCsr->nRec]
|| pCsr->iField>=DBDATA_MX_FIELD
){
bNextPage = 1;
@@ -681,8 +731,8 @@ static int dbdataNext(sqlite3_vtab_cursor *pCursor){
int szField = 0;
pCsr->pHdrPtr += dbdataGetVarintU32(pCsr->pHdrPtr, &iType);
szField = dbdataValueBytes(iType);
- if( (pCsr->nRec - (pCsr->pPtr - pCsr->pRec))<szField ){
- pCsr->pPtr = &pCsr->pRec[pCsr->nRec];
+ if( (pCsr->nRec - (pCsr->pPtr - pCsr->rec.aBuf))<szField ){
+ pCsr->pPtr = &pCsr->rec.aBuf[pCsr->nRec];
}else{
pCsr->pPtr += szField;
}
@@ -692,20 +742,18 @@ static int dbdataNext(sqlite3_vtab_cursor *pCursor){
if( bNextPage ){
sqlite3_free(pCsr->aPage);
- sqlite3_free(pCsr->pRec);
pCsr->aPage = 0;
- pCsr->pRec = 0;
+ pCsr->nRec = 0;
if( pCsr->bOnePage ) return SQLITE_OK;
pCsr->iPgno++;
}else{
- if( pCsr->iField<0 || pCsr->pHdrPtr<&pCsr->pRec[pCsr->nHdr] ){
+ if( pCsr->iField<0 || pCsr->pHdrPtr<&pCsr->rec.aBuf[pCsr->nHdr] ){
return SQLITE_OK;
}
/* Advance to the next cell. The next iteration of the loop will load
** the record and so on. */
- sqlite3_free(pCsr->pRec);
- pCsr->pRec = 0;
+ pCsr->nRec = 0;
pCsr->iCell++;
}
}
@@ -895,12 +943,12 @@ static int dbdataColumn(
case DBDATA_COLUMN_VALUE: {
if( pCsr->iField<0 ){
sqlite3_result_int64(ctx, pCsr->iIntkey);
- }else if( &pCsr->pRec[pCsr->nRec] >= pCsr->pPtr ){
+ }else if( &pCsr->rec.aBuf[pCsr->nRec] >= pCsr->pPtr ){
sqlite3_int64 iType;
dbdataGetVarintU32(pCsr->pHdrPtr, &iType);
dbdataValue(
ctx, pCsr->enc, iType, pCsr->pPtr,
- &pCsr->pRec[pCsr->nRec] - pCsr->pPtr
+ &pCsr->rec.aBuf[pCsr->nRec] - pCsr->pPtr
);
}
break;
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-01 07:43:34 +0000