Beispiel #1
0
/*
** Malloc function used within this file to allocate space from the buffer
** configured using sqlite3_config(SQLITE_CONFIG_PAGECACHE) option. If no
** such buffer exists or there is no space left in it, this function falls
** back to sqlite3Malloc().
**
** Multiple threads can run this routine at the same time.  Global variables
** in pcache1 need to be protected via mutex.
*/
static void *pcache1Alloc(int nByte){
  void *p = 0;
  assert( sqlite3_mutex_notheld(pcache1.grp.mutex) );
  if( nByte<=pcache1.szSlot ){
    sqlite3_mutex_enter(pcache1.mutex);
    p = (PgHdr1 *)pcache1.pFree;
    if( p ){
      pcache1.pFree = pcache1.pFree->pNext;
      pcache1.nFreeSlot--;
      pcache1.bUnderPressure = pcache1.nFreeSlot<pcache1.nReserve;
      assert( pcache1.nFreeSlot>=0 );
      sqlite3StatusHighwater(SQLITE_STATUS_PAGECACHE_SIZE, nByte);
      sqlite3StatusUp(SQLITE_STATUS_PAGECACHE_USED, 1);
    }
    sqlite3_mutex_leave(pcache1.mutex);
  }
  if( p==0 ){
    /* Memory is not available in the SQLITE_CONFIG_PAGECACHE pool.  Get
    ** it from sqlite3Malloc instead.
    */
    p = sqlite3Malloc(nByte);
#ifndef SQLITE_DISABLE_PAGECACHE_OVERFLOW_STATS
    if( p ){
      int sz = sqlite3MallocSize(p);
      sqlite3_mutex_enter(pcache1.mutex);
      sqlite3StatusHighwater(SQLITE_STATUS_PAGECACHE_SIZE, nByte);
      sqlite3StatusUp(SQLITE_STATUS_PAGECACHE_OVERFLOW, sz);
      sqlite3_mutex_leave(pcache1.mutex);
    }
#endif
    sqlite3MemdebugSetType(p, MEMTYPE_PCACHE);
  }
  return p;
}
/*
** Do a memory allocation with statistics and alarms.  Assume the
** lock is already held.
*/
static int mallocWithAlarm(int n, void **pp){
  int nFull;
  void *p;
  assert( sqlite3_mutex_held(mem0.mutex) );
  nFull = sqlite3GlobalConfig.m.xRoundup(n);
  sqlite3StatusHighwater(SQLITE_STATUS_MALLOC_SIZE, n);
  if( mem0.alarmThreshold>0 ){
    sqlite3_int64 nUsed = sqlite3StatusValue(SQLITE_STATUS_MEMORY_USED);
    if( nUsed >= mem0.alarmThreshold - nFull ){
      mem0.nearlyFull = 1;
      sqlite3MallocAlarm(nFull);
    }else{
      mem0.nearlyFull = 0;
    }
  }
  p = sqlite3GlobalConfig.m.xMalloc(nFull);
#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
  if( p==0 && mem0.alarmThreshold>0 ){
    sqlite3MallocAlarm(nFull);
    p = sqlite3GlobalConfig.m.xMalloc(nFull);
  }
#endif
  if( p ){
    nFull = sqlite3MallocSize(p);
    sqlite3StatusUp(SQLITE_STATUS_MEMORY_USED, nFull);
    sqlite3StatusUp(SQLITE_STATUS_MALLOC_COUNT, 1);
  }
  *pp = p;
  return nFull;
}
/*
** Change the size of an existing memory allocation
*/
void *sqlite3Realloc(void *pOld, u64 nBytes){
  int nOld, nNew, nDiff;
  void *pNew;
  assert( sqlite3MemdebugHasType(pOld, MEMTYPE_HEAP) );
  assert( sqlite3MemdebugNoType(pOld, (u8)~MEMTYPE_HEAP) );
  if( pOld==0 ){
    return sqlite3Malloc(nBytes); /* IMP: R-04300-56712 */
  }
  if( nBytes==0 ){
    sqlite3_free(pOld); /* IMP: R-26507-47431 */
    return 0;
  }
  if( nBytes>=0x7fffff00 ){
    /* The 0x7ffff00 limit term is explained in comments on sqlite3Malloc() */
    return 0;
  }
  nOld = sqlite3MallocSize(pOld);
  /* IMPLEMENTATION-OF: R-46199-30249 SQLite guarantees that the second
  ** argument to xRealloc is always a value returned by a prior call to
  ** xRoundup. */
  nNew = sqlite3GlobalConfig.m.xRoundup((int)nBytes);
  if( nOld==nNew ){
    pNew = pOld;
  }else if( sqlite3GlobalConfig.bMemstat ){
    sqlite3_mutex_enter(mem0.mutex);
    sqlite3StatusHighwater(SQLITE_STATUS_MALLOC_SIZE, (int)nBytes);
    nDiff = nNew - nOld;
    if( sqlite3StatusValue(SQLITE_STATUS_MEMORY_USED) >= 
          mem0.alarmThreshold-nDiff ){
      sqlite3MallocAlarm(nDiff);
    }
    pNew = sqlite3GlobalConfig.m.xRealloc(pOld, nNew);
    if( pNew==0 && mem0.alarmThreshold>0 ){
      sqlite3MallocAlarm((int)nBytes);
      pNew = sqlite3GlobalConfig.m.xRealloc(pOld, nNew);
    }
    if( pNew ){
      nNew = sqlite3MallocSize(pNew);
      sqlite3StatusUp(SQLITE_STATUS_MEMORY_USED, nNew-nOld);
    }
    sqlite3_mutex_leave(mem0.mutex);
  }else{
    pNew = sqlite3GlobalConfig.m.xRealloc(pOld, nNew);
  }
  assert( EIGHT_BYTE_ALIGNMENT(pNew) ); /* IMP: R-11148-40995 */
  return pNew;
}
Beispiel #4
0
/*
** Do a memory allocation with statistics and alarms.  Assume the
** lock is already held.
*/
static void mallocWithAlarm(int n, void **pp){
  void *p;
  int nFull;
  assert( sqlite3_mutex_held(mem0.mutex) );
  assert( n>0 );

  /* In Firefox (circa 2017-02-08), xRoundup() is remapped to an internal
  ** implementation of malloc_good_size(), which must be called in debug
  ** mode and specifically when the DMD "Dark Matter Detector" is enabled
  ** or else a crash results.  Hence, do not attempt to optimize out the
  ** following xRoundup() call. */
  nFull = sqlite3GlobalConfig.m.xRoundup(n);

#ifdef SQLITE_MAX_MEMORY
  if( sqlite3StatusValue(SQLITE_STATUS_MEMORY_USED)+nFull>SQLITE_MAX_MEMORY ){
    *pp = 0;
    return;
  }
#endif

  sqlite3StatusHighwater(SQLITE_STATUS_MALLOC_SIZE, n);
  if( mem0.alarmThreshold>0 ){
    sqlite3_int64 nUsed = sqlite3StatusValue(SQLITE_STATUS_MEMORY_USED);
    if( nUsed >= mem0.alarmThreshold - nFull ){
      mem0.nearlyFull = 1;
      sqlite3MallocAlarm(nFull);
    }else{
      mem0.nearlyFull = 0;
    }
  }
  p = sqlite3GlobalConfig.m.xMalloc(nFull);
#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
  if( p==0 && mem0.alarmThreshold>0 ){
    sqlite3MallocAlarm(nFull);
    p = sqlite3GlobalConfig.m.xMalloc(nFull);
  }
#endif
  if( p ){
    nFull = sqlite3MallocSize(p);
    sqlite3StatusUp(SQLITE_STATUS_MEMORY_USED, nFull);
    sqlite3StatusUp(SQLITE_STATUS_MALLOC_COUNT, 1);
  }
  *pp = p;
}
/*
** Allocate memory that is to be used and released right away.
** This routine is similar to alloca() in that it is not intended
** for situations where the memory might be held long-term.  This
** routine is intended to get memory to old large transient data
** structures that would not normally fit on the stack of an
** embedded processor.
*/
void *sqlite3ScratchMalloc(int n){
  void *p;
  assert( n>0 );

  sqlite3_mutex_enter(mem0.mutex);
  sqlite3StatusHighwater(SQLITE_STATUS_SCRATCH_SIZE, n);
  if( mem0.nScratchFree && sqlite3GlobalConfig.szScratch>=n ){
    p = mem0.pScratchFree;
    mem0.pScratchFree = mem0.pScratchFree->pNext;
    mem0.nScratchFree--;
    sqlite3StatusUp(SQLITE_STATUS_SCRATCH_USED, 1);
    sqlite3_mutex_leave(mem0.mutex);
  }else{
    sqlite3_mutex_leave(mem0.mutex);
    p = sqlite3Malloc(n);
    if( sqlite3GlobalConfig.bMemstat && p ){
      sqlite3_mutex_enter(mem0.mutex);
      sqlite3StatusUp(SQLITE_STATUS_SCRATCH_OVERFLOW, sqlite3MallocSize(p));
      sqlite3_mutex_leave(mem0.mutex);
    }
    sqlite3MemdebugSetType(p, MEMTYPE_SCRATCH);
  }
  assert( sqlite3_mutex_notheld(mem0.mutex) );


#if SQLITE_THREADSAFE==0 && !defined(NDEBUG)
  /* EVIDENCE-OF: R-12970-05880 SQLite will not use more than one scratch
  ** buffers per thread.
  **
  ** This can only be checked in single-threaded mode.
  */
  assert( scratchAllocOut==0 );
  if( p ) scratchAllocOut++;
#endif

  return p;
}
Beispiel #6
0
/*
** Run the parser on the given SQL string.  The parser structure is
** passed in.  An SQLITE_ status code is returned.  If an error occurs
** then an and attempt is made to write an error message into 
** memory obtained from sqlite3_malloc() and to make *pzErrMsg point to that
** error message.
*/
int sqlite3RunParser(Parse *pParse, const char *zSql, char **pzErrMsg){
  int nErr = 0;                   /* Number of errors encountered */
  void *pEngine;                  /* The LEMON-generated LALR(1) parser */
  int n = 0;                      /* Length of the next token token */
  int tokenType;                  /* type of the next token */
  int lastTokenParsed = -1;       /* type of the previous token */
  sqlite3 *db = pParse->db;       /* The database connection */
  int mxSqlLen;                   /* Max length of an SQL string */
#ifdef sqlite3Parser_ENGINEALWAYSONSTACK
  yyParser sEngine;    /* Space to hold the Lemon-generated Parser object */
#endif

  assert( zSql!=0 );
  mxSqlLen = db->aLimit[SQLITE_LIMIT_SQL_LENGTH];
  if( db->nVdbeActive==0 ){
    db->u1.isInterrupted = 0;
  }
  pParse->rc = SQLITE_OK;
  pParse->zTail = zSql;
  assert( pzErrMsg!=0 );
#ifdef SQLITE_DEBUG
  if( db->flags & SQLITE_ParserTrace ){
    printf("parser: [[[%s]]]\n", zSql);
    sqlite3ParserTrace(stdout, "parser: ");
  }else{
    sqlite3ParserTrace(0, 0);
  }
#endif
#ifdef sqlite3Parser_ENGINEALWAYSONSTACK
  pEngine = &sEngine;
  sqlite3ParserInit(pEngine, pParse);
#else
  pEngine = sqlite3ParserAlloc(sqlite3Malloc, pParse);
  if( pEngine==0 ){
    sqlite3OomFault(db);
    return SQLITE_NOMEM_BKPT;
  }
#endif
  assert( pParse->pNewTable==0 );
  assert( pParse->pNewTrigger==0 );
  assert( pParse->nVar==0 );
  assert( pParse->pVList==0 );
  while( 1 ){
    n = sqlite3GetToken((u8*)zSql, &tokenType);
    mxSqlLen -= n;
    if( mxSqlLen<0 ){
      pParse->rc = SQLITE_TOOBIG;
      break;
    }
#ifndef SQLITE_OMIT_WINDOWFUNC
    if( tokenType>=TK_WINDOW ){
      assert( tokenType==TK_SPACE || tokenType==TK_OVER || tokenType==TK_FILTER
           || tokenType==TK_ILLEGAL || tokenType==TK_WINDOW 
      );
#else
    if( tokenType>=TK_SPACE ){
      assert( tokenType==TK_SPACE || tokenType==TK_ILLEGAL );
#endif /* SQLITE_OMIT_WINDOWFUNC */
      if( db->u1.isInterrupted ){
        pParse->rc = SQLITE_INTERRUPT;
        break;
      }
      if( tokenType==TK_SPACE ){
        zSql += n;
        continue;
      }
      if( zSql[0]==0 ){
        /* Upon reaching the end of input, call the parser two more times
        ** with tokens TK_SEMI and 0, in that order. */
        if( lastTokenParsed==TK_SEMI ){
          tokenType = 0;
        }else if( lastTokenParsed==0 ){
          break;
        }else{
          tokenType = TK_SEMI;
        }
        n = 0;
#ifndef SQLITE_OMIT_WINDOWFUNC
      }else if( tokenType==TK_WINDOW ){
        assert( n==6 );
        tokenType = analyzeWindowKeyword((const u8*)&zSql[6]);
      }else if( tokenType==TK_OVER ){
        assert( n==4 );
        tokenType = analyzeOverKeyword((const u8*)&zSql[4], lastTokenParsed);
      }else if( tokenType==TK_FILTER ){
        assert( n==6 );
        tokenType = analyzeFilterKeyword((const u8*)&zSql[6], lastTokenParsed);
#endif /* SQLITE_OMIT_WINDOWFUNC */
      }else{
        sqlite3ErrorMsg(pParse, "unrecognized token: \"%.*s\"", n, zSql);
        break;
      }
    }
    pParse->sLastToken.z = zSql;
    pParse->sLastToken.n = n;
    sqlite3Parser(pEngine, tokenType, pParse->sLastToken);
    lastTokenParsed = tokenType;
    zSql += n;
    if( pParse->rc!=SQLITE_OK || db->mallocFailed ) break;
  }
  assert( nErr==0 );
#ifdef YYTRACKMAXSTACKDEPTH
  sqlite3_mutex_enter(sqlite3MallocMutex());
  sqlite3StatusHighwater(SQLITE_STATUS_PARSER_STACK,
      sqlite3ParserStackPeak(pEngine)
  );
  sqlite3_mutex_leave(sqlite3MallocMutex());
#endif /* YYDEBUG */
#ifdef sqlite3Parser_ENGINEALWAYSONSTACK
  sqlite3ParserFinalize(pEngine);
#else
  sqlite3ParserFree(pEngine, sqlite3_free);
#endif
  if( db->mallocFailed ){
    pParse->rc = SQLITE_NOMEM_BKPT;
  }
  if( pParse->rc!=SQLITE_OK && pParse->rc!=SQLITE_DONE && pParse->zErrMsg==0 ){
    pParse->zErrMsg = sqlite3MPrintf(db, "%s", sqlite3ErrStr(pParse->rc));
  }
  assert( pzErrMsg!=0 );
  if( pParse->zErrMsg ){
    *pzErrMsg = pParse->zErrMsg;
    sqlite3_log(pParse->rc, "%s in \"%s\"", 
                *pzErrMsg, pParse->zTail);
    pParse->zErrMsg = 0;
    nErr++;
  }
  pParse->zTail = zSql;
  if( pParse->pVdbe && pParse->nErr>0 && pParse->nested==0 ){
    sqlite3VdbeDelete(pParse->pVdbe);
    pParse->pVdbe = 0;
  }
#ifndef SQLITE_OMIT_SHARED_CACHE
  if( pParse->nested==0 ){
    sqlite3DbFree(db, pParse->aTableLock);
    pParse->aTableLock = 0;
    pParse->nTableLock = 0;
  }
#endif
#ifndef SQLITE_OMIT_VIRTUALTABLE
  sqlite3_free(pParse->apVtabLock);
#endif

  if( !IN_SPECIAL_PARSE ){
    /* If the pParse->declareVtab flag is set, do not delete any table 
    ** structure built up in pParse->pNewTable. The calling code (see vtab.c)
    ** will take responsibility for freeing the Table structure.
    */
    sqlite3DeleteTable(db, pParse->pNewTable);
  }
  if( !IN_RENAME_OBJECT ){
    sqlite3DeleteTrigger(db, pParse->pNewTrigger);
  }

  if( pParse->pWithToFree ) sqlite3WithDelete(db, pParse->pWithToFree);
  sqlite3DbFree(db, pParse->pVList);
  while( pParse->pAinc ){
    AutoincInfo *p = pParse->pAinc;
    pParse->pAinc = p->pNext;
    sqlite3DbFreeNN(db, p);
  }
  while( pParse->pZombieTab ){
    Table *p = pParse->pZombieTab;
    pParse->pZombieTab = p->pNextZombie;
    sqlite3DeleteTable(db, p);
  }
  assert( nErr==0 || pParse->rc!=SQLITE_OK );
  return nErr;
}


#ifdef SQLITE_ENABLE_NORMALIZE
/*
** Insert a single space character into pStr if the current string
** ends with an identifier
*/
static void addSpaceSeparator(sqlite3_str *pStr){
  if( pStr->nChar && sqlite3IsIdChar(pStr->zText[pStr->nChar-1]) ){
    sqlite3_str_append(pStr, " ", 1);
  }
}

/*
** Compute a normalization of the SQL given by zSql[0..nSql-1].  Return
** the normalization in space obtained from sqlite3DbMalloc().  Or return
** NULL if anything goes wrong or if zSql is NULL.
*/
char *sqlite3Normalize(
  Vdbe *pVdbe,       /* VM being reprepared */
  const char *zSql   /* The original SQL string */
){
  sqlite3 *db;       /* The database connection */
  int i;             /* Next unread byte of zSql[] */
  int n;             /* length of current token */
  int tokenType;     /* type of current token */
  int prevType = 0;  /* Previous non-whitespace token */
  int nParen;        /* Number of nested levels of parentheses */
  int iStartIN;      /* Start of RHS of IN operator in z[] */
  int nParenAtIN;    /* Value of nParent at start of RHS of IN operator */
  int j;             /* Bytes of normalized SQL generated so far */
  sqlite3_str *pStr; /* The normalized SQL string under construction */

  db = sqlite3VdbeDb(pVdbe);
  tokenType = -1;
  nParen = iStartIN = nParenAtIN = 0;
  pStr = sqlite3_str_new(db);
  assert( pStr!=0 );  /* sqlite3_str_new() never returns NULL */
  for(i=0; zSql[i] && pStr->accError==0; i+=n){
    if( tokenType!=TK_SPACE ){
      prevType = tokenType;
    }
    n = sqlite3GetToken((unsigned char*)zSql+i, &tokenType);
    if( NEVER(n<=0) ) break;
    switch( tokenType ){
      case TK_SPACE: {
        break;
      }
      case TK_NULL: {
        if( prevType==TK_IS || prevType==TK_NOT ){
          sqlite3_str_append(pStr, " NULL", 5);
          break;
        }
        /* Fall through */
      }
      case TK_STRING:
      case TK_INTEGER:
      case TK_FLOAT:
      case TK_VARIABLE:
      case TK_BLOB: {
        sqlite3_str_append(pStr, "?", 1);
        break;
      }
      case TK_LP: {
        nParen++;
        if( prevType==TK_IN ){
          iStartIN = pStr->nChar;
          nParenAtIN = nParen;
        }
        sqlite3_str_append(pStr, "(", 1);
        break;
      }
      case TK_RP: {
        if( iStartIN>0 && nParen==nParenAtIN ){
          assert( pStr->nChar>=iStartIN );
          pStr->nChar = iStartIN+1;
          sqlite3_str_append(pStr, "?,?,?", 5);
          iStartIN = 0;
        }
        nParen--;
        sqlite3_str_append(pStr, ")", 1);
        break;
      }
      case TK_ID: {
        iStartIN = 0;
        j = pStr->nChar;
        if( sqlite3Isquote(zSql[i]) ){
          char *zId = sqlite3DbStrNDup(db, zSql+i, n);
          int nId;
          int eType = 0;
          if( zId==0 ) break;
          sqlite3Dequote(zId);
          if( zSql[i]=='"' && sqlite3VdbeUsesDoubleQuotedString(pVdbe, zId) ){
            sqlite3_str_append(pStr, "?", 1);
            sqlite3DbFree(db, zId);
            break;
          }
          nId = sqlite3Strlen30(zId);
          if( sqlite3GetToken((u8*)zId, &eType)==nId && eType==TK_ID ){
            addSpaceSeparator(pStr);
            sqlite3_str_append(pStr, zId, nId);
          }else{
            sqlite3_str_appendf(pStr, "\"%w\"", zId);
          }
          sqlite3DbFree(db, zId);
        }else{
          addSpaceSeparator(pStr);
          sqlite3_str_append(pStr, zSql+i, n);
        }
        while( j<pStr->nChar ){
          pStr->zText[j] = sqlite3Tolower(pStr->zText[j]);
          j++;
        }
        break;
      }
      case TK_SELECT: {
        iStartIN = 0;
        /* fall through */
      }
      default: {
        if( sqlite3IsIdChar(zSql[i]) ) addSpaceSeparator(pStr);
        j = pStr->nChar;
        sqlite3_str_append(pStr, zSql+i, n);
        while( j<pStr->nChar ){
          pStr->zText[j] = sqlite3Toupper(pStr->zText[j]);
          j++;
        }
        break;
      }
    }
  }
  if( tokenType!=TK_SEMI ) sqlite3_str_append(pStr, ";", 1);
  return sqlite3_str_finish(pStr);
}