SQLite

/*
** 2003 Feb 4
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** $Id: btree_rb.c,v 1.23 2004/02/12 15:31:21 drh Exp $
**
** This file implements an in-core database using Red-Black balanced
** binary trees.
** 
** It was contributed to SQLite by anonymous on 2003-Feb-04 23:24:49 UTC.
*/
#include "btree.h"

/*
 * A string-manipulation helper function for check_redblack_tree(). If (orig ==
 * NULL) a copy of val is returned. If (orig != NULL) then a copy of the *
 * concatenation of orig and val is returned. The original orig is deleted
 * (using sqliteFree()).
 */
static char *append_val(char * orig, char const * val)
{

  if( !orig ){
    return sqliteStrDup( val );
  } else{
    char * ret = 0;
    sqliteSetString(&ret, orig, val, (char*)0);
    sqliteFree( orig );
    return ret;
  }
  assert(0);
}

/*
 * Append a string representation of the entire node to orig and return it.
 * This is used to produce debugging information if check_redblack_tree() finds
 * a problem with a red-black binary tree.
 */

}

static int memRbtreeKey(RbtCursor* pCur, int offset, int amt, char *zBuf)
{
  if( !pCur->pNode ) return 0;
  if( !pCur->pNode->pKey || ((amt + offset) <= pCur->pNode->nKey) ){
    memcpy(zBuf, ((char*)pCur->pNode->pKey)+offset, amt);
    return amt;
  }else{
    memcpy(zBuf, ((char*)pCur->pNode->pKey)+offset, pCur->pNode->nKey-offset);
    return pCur->pNode->nKey-offset;
  }
  assert(0);
}

static int memRbtreeDataSize(RbtCursor* pCur, int *pSize)
{
  if( pCur->pNode ){
    *pSize = pCur->pNode->nData;
  }else{
    *pSize = 0;
  }
  return SQLITE_OK;
}

static int memRbtreeData(RbtCursor *pCur, int offset, int amt, char *zBuf)
{
  if( !pCur->pNode ) return 0;
  if( (amt + offset) <= pCur->pNode->nData ){
    memcpy(zBuf, ((char*)pCur->pNode->pData)+offset, amt);
    return amt;
  }else{
    memcpy(zBuf, ((char*)pCur->pNode->pData)+offset ,pCur->pNode->nData-offset);
    return pCur->pNode->nData-offset;
  }
  assert(0);
}

static int memRbtreeCloseCursor(RbtCursor* pCur)
{
  if( pCur->pTree->pCursors==pCur ){
    pCur->pTree->pCursors = pCur->pShared;
  }else{

** the LockFileEx() API.  But we can still statically link against that
** API as long as we don't call it win running Win95/98/ME.  A call to
** this routine is used to determine if the host is Win95/98/ME or
** WinNT/2K/XP so that we will know whether or not we can safely call
** the LockFileEx() API.
*/
int isNT(void){
  static osType = 0;   /* 0=unknown 1=win95 2=winNT */
  if( osType==0 ){
    OSVERSIONINFO sInfo;
    sInfo.dwOSVersionInfoSize = sizeof(sInfo);
    GetVersionEx(&sInfo);
    osType = sInfo.dwPlatformId==VER_PLATFORM_WIN32_NT ? 2 : 1;
  }
  return osType==2;

          }else if( flag_plussign )  prefix = '+';
          else if( flag_blanksign )  prefix = ' ';
          else                       prefix = 0;
        }else                        prefix = 0;
        if( flag_zeropad && precision<width-(prefix!=0) ){
          precision = width-(prefix!=0);
        }
        bufpt = &buf[etBUFSIZE];
        {
          register char *cset;      /* Use registers for speed */
          register int base;
          cset = infop->charset;
          base = infop->base;
          do{                                           /* Convert to ascii */
            *(--bufpt) = cset[longvalue%base];
            longvalue = longvalue/base;
          }while( longvalue>0 );
        }
        length = &buf[etBUFSIZE]-bufpt;
        for(idx=precision-length; idx>0; idx--){
          *(--bufpt) = '0';                             /* Zero pad */
        }
        if( prefix ) *(--bufpt) = prefix;               /* Add sign */
        if( flag_alternateform && infop->prefix ){      /* Add "0" or "0x" */
          char *pre, x;
          pre = infop->prefix;
          if( *bufpt!=pre[0] ){
            for(pre=infop->prefix; (x=(*pre))!=0; pre++) *(--bufpt) = x;
          }
        }
        length = &buf[etBUFSIZE]-bufpt;
        break;
      case etFLOAT:
      case etEXP:
      case etGENERIC:
        realvalue = va_arg(ap,double);
#ifndef etNOFLOATINGPOINT
        if( precision<0 ) precision = 6;         /* Set default precision */