u32 szUncompressed;
  u16 nFile;
  u16 nExtra;
};

typedef struct ZipfileEntry ZipfileEntry;
struct ZipfileEntry {
  char *zPath;               /* Path of zipfile entry */
  u8 *aCdsEntry;             /* Buffer containing entire CDS entry */
  int nCdsEntry;             /* Size of buffer aCdsEntry[] in bytes */
  int bDeleted;              /* True if entry has been deleted */
  ZipfileEntry *pNext;       /* Next element in in-memory CDS */
};

/* 
** Cursor type for recursively iterating through a directory structure.
*/
typedef struct ZipfileCsr ZipfileCsr;
struct ZipfileCsr {
  sqlite3_vtab_cursor base;  /* Base class - must be first */
  i64 iId;                   /* Cursor ID */
  int bEof;                  /* True when at EOF */


  /* Used outside of write transactions */
  FILE *pFile;               /* Zip file */
  i64 iNextOff;              /* Offset of next record in central directory */
  ZipfileEOCD eocd;          /* Parse of central directory record */

  /* Used inside write transactions */
  ZipfileEntry *pCurrent;

  ZipfileCDS cds;            /* Central Directory Structure */
  ZipfileLFH lfh;            /* Local File Header for current entry */
  i64 iDataOff;              /* Offset in zipfile to data */
  u32 mTime;                 /* Extended mtime value */
  int flags;                 /* Flags byte (see below for bits) */
  ZipfileCsr *pCsrNext;      /* Next cursor on same virtual table */
};







/*
** Values for ZipfileCsr.flags.
*/
#define ZIPFILE_MTIME_VALID 0x0001

typedef struct ZipfileTab ZipfileTab;
struct ZipfileTab {
  sqlite3_vtab base;         /* Base class - must be first */
  char *zFile;               /* Zip file this table accesses (may be NULL) */
  u8 *aBuffer;               /* Temporary buffer used for various tasks */

................................................................................
      memcpy(pNew->zFile, zFile, nFile);
      zipfileDequote(pNew->zFile);
    }
  }
  *ppVtab = (sqlite3_vtab*)pNew;
  return rc;
}


























/*
** This method is the destructor for zipfile vtab objects.
*/
static int zipfileDisconnect(sqlite3_vtab *pVtab){

  sqlite3_free(pVtab);
  return SQLITE_OK;
}

/*
** Constructor for a new ZipfileCsr object.
*/
................................................................................
}

/*
** Reset a cursor back to the state it was in when first returned
** by zipfileOpen().
*/
static void zipfileResetCursor(ZipfileCsr *pCsr){
  sqlite3_free(pCsr->cds.zFile);
  pCsr->cds.zFile = 0;
  pCsr->bEof = 0;
  if( pCsr->pFile ){
    fclose(pCsr->pFile);
    pCsr->pFile = 0;


  }
}

/*
** Destructor for an ZipfileCsr.
*/
static int zipfileClose(sqlite3_vtab_cursor *cur){
................................................................................
    assert( aRead==&aBuf[ZIPFILE_CDS_FIXED_SZ] );
  }

  return rc;
}

/*
** Read the CDS record for the current entry from disk into pCsr->cds.
*/
static int zipfileCsrReadCDS(ZipfileCsr *pCsr){
  char **pzErr = &pCsr->base.pVtab->zErrMsg;
  u8 *aRead;
  int rc = SQLITE_OK;

  sqlite3_free(pCsr->cds.zFile);
  pCsr->cds.zFile = 0;

  if( pCsr->pCurrent==0 ){
    aRead = zipfileCsrBuffer(pCsr);
    rc = zipfileReadData(
        pCsr->pFile, aRead, ZIPFILE_CDS_FIXED_SZ, pCsr->iNextOff, pzErr
    );
  }else{
    aRead = pCsr->pCurrent->aCdsEntry;
  }

  if( rc==SQLITE_OK ){
    rc = zipfileReadCDS(aRead, &pCsr->cds);
    if( rc!=SQLITE_OK ){
      assert( pCsr->pCurrent==0 );
      zipfileSetErrmsg(pCsr,"failed to read CDS at offset %lld",pCsr->iNextOff);
    }else{
      int nRead;
      if( pCsr->pCurrent==0 ){
        nRead = pCsr->cds.nFile + pCsr->cds.nExtra;
        aRead = zipfileCsrBuffer(pCsr);
        pCsr->iNextOff += ZIPFILE_CDS_FIXED_SZ;
        rc = zipfileReadData(pCsr->pFile, aRead, nRead, pCsr->iNextOff, pzErr);
      }else{
        aRead = &aRead[ZIPFILE_CDS_FIXED_SZ];
      }

      if( rc==SQLITE_OK ){
        pCsr->cds.zFile = sqlite3_mprintf("%.*s", (int)pCsr->cds.nFile, aRead);
        pCsr->iNextOff += pCsr->cds.nFile;
        pCsr->iNextOff += pCsr->cds.nExtra;
        pCsr->iNextOff += pCsr->cds.nComment;
      }

      /* Scan the cds.nExtra bytes of "extra" fields for any that can
      ** be interpreted. The general format of an extra field is:
      **
      **   Header ID    2 bytes
      **   Data Size    2 bytes
      **   Data         N bytes
      **
      */
      if( rc==SQLITE_OK ){
        u8 *p = &aRead[pCsr->cds.nFile];



        u8 *pEnd = &p[pCsr->cds.nExtra];

        while( p<pEnd ){
          u16 id = zipfileRead16(p);
          u16 nByte = zipfileRead16(p);

          switch( id ){
            case ZIPFILE_EXTRA_TIMESTAMP: {
              u8 b = p[0];
              if( b & 0x01 ){     /* 0x01 -> modtime is present */
                pCsr->mTime = zipfileGetU32(&p[1]);
                pCsr->flags |= ZIPFILE_MTIME_VALID;

              }
              break;
            }
          }

          p += nByte;
        }

      }


















































































    }
  }

  return rc;
}

static FILE *zipfileGetFd(ZipfileCsr *pCsr){
................................................................................
  return rc;
}

static int zipfileCsrReadLFH(ZipfileCsr *pCsr){
  FILE *pFile = zipfileGetFd(pCsr);
  char **pzErr = &pCsr->base.pVtab->zErrMsg;
  u8 *aRead = zipfileCsrBuffer(pCsr);

  int rc = zipfileReadLFH(pFile, pCsr->cds.iOffset, aRead, &pCsr->lfh, pzErr);
  pCsr->iDataOff =  pCsr->cds.iOffset + ZIPFILE_LFH_FIXED_SZ;
  pCsr->iDataOff += pCsr->lfh.nFile+pCsr->lfh.nExtra;
  return rc;
}


/*
** Advance an ZipfileCsr to its next row of output.
*/
static int zipfileNext(sqlite3_vtab_cursor *cur){
  ZipfileCsr *pCsr = (ZipfileCsr*)cur;
  int rc = SQLITE_OK;
  pCsr->flags = 0;

  if( pCsr->pCurrent==0 ){
    i64 iEof = pCsr->eocd.iOffset + pCsr->eocd.nSize;


    if( pCsr->iNextOff>=iEof ){
      pCsr->bEof = 1;







    }


  }else{
    assert( pCsr->pFile==0 );
    do {

      pCsr->pCurrent = pCsr->pCurrent->pNext;
    }while( pCsr->pCurrent && pCsr->pCurrent->bDeleted );

    if( pCsr->pCurrent==0 ){
      pCsr->bEof = 1;
    }
  }

  if( pCsr->bEof==0 ){
    rc = zipfileCsrReadCDS(pCsr);
    if( rc==SQLITE_OK ){
      rc = zipfileCsrReadLFH(pCsr);
    }
  }

  return rc;
}

/*
** "Standard" MS-DOS time format:
**
**   File modification time:
**     Bits 00-04: seconds divided by 2
**     Bits 05-10: minute
**     Bits 11-15: hour
**   File modification date:
**     Bits 00-04: day
**     Bits 05-08: month (1-12)
**     Bits 09-15: years from 1980 
*/
static time_t zipfileMtime(ZipfileCsr *pCsr){
  struct tm t;
  memset(&t, 0, sizeof(t));
  t.tm_sec = (pCsr->cds.mTime & 0x1F)*2;
  t.tm_min = (pCsr->cds.mTime >> 5) & 0x2F;
  t.tm_hour = (pCsr->cds.mTime >> 11) & 0x1F;

  t.tm_mday = (pCsr->cds.mDate & 0x1F);
  t.tm_mon = ((pCsr->cds.mDate >> 5) & 0x0F) - 1;
  t.tm_year = 80 + ((pCsr->cds.mDate >> 9) & 0x7F);

  return mktime(&t);
}

static void zipfileMtimeToDos(ZipfileCDS *pCds, u32 mTime){
  time_t t = (time_t)mTime;
  struct tm res;

#if !defined(_WIN32) && !defined(WIN32)
  localtime_r(&t, &res);
#else
................................................................................
*/
static int zipfileColumn(
  sqlite3_vtab_cursor *cur,   /* The cursor */
  sqlite3_context *ctx,       /* First argument to sqlite3_result_...() */
  int i                       /* Which column to return */
){
  ZipfileCsr *pCsr = (ZipfileCsr*)cur;

  int rc = SQLITE_OK;
  switch( i ){
    case 0:   /* name */
      sqlite3_result_text(ctx, pCsr->cds.zFile, -1, SQLITE_TRANSIENT);
      break;
    case 1:   /* mode */
      /* TODO: Whether or not the following is correct surely depends on
      ** the platform on which the archive was created.  */
      sqlite3_result_int(ctx, pCsr->cds.iExternalAttr >> 16);
      break;
    case 2: { /* mtime */
      if( pCsr->flags & ZIPFILE_MTIME_VALID ){
        sqlite3_result_int64(ctx, pCsr->mTime);
      }else{
        sqlite3_result_int64(ctx, zipfileMtime(pCsr));
      }
      break;
    }
    case 3: { /* sz */
      if( sqlite3_vtab_nochange(ctx)==0 ){
        sqlite3_result_int64(ctx, pCsr->cds.szUncompressed);
      }
      break;
    }
    case 4:   /* rawdata */
      if( sqlite3_vtab_nochange(ctx) ) break;
    case 5: { /* data */
      if( i==4 || pCsr->cds.iCompression==0 || pCsr->cds.iCompression==8 ){
        int sz = pCsr->cds.szCompressed;
        int szFinal = pCsr->cds.szUncompressed;
        if( szFinal>0 ){
          u8 *aBuf = sqlite3_malloc(sz);
          if( aBuf==0 ){
            rc = SQLITE_NOMEM;
          }else{
            FILE *pFile = zipfileGetFd(pCsr);
            rc = zipfileReadData(pFile, aBuf, sz, pCsr->iDataOff,
                &pCsr->base.pVtab->zErrMsg
            );
          }
          if( rc==SQLITE_OK ){
            if( i==5 && pCsr->cds.iCompression ){
              zipfileInflate(ctx, aBuf, sz, szFinal);
            }else{
              sqlite3_result_blob(ctx, aBuf, sz, SQLITE_TRANSIENT);
            }
            sqlite3_free(aBuf);
          }
        }else{
          /* Figure out if this is a directory or a zero-sized file. Consider
          ** it to be a directory either if the mode suggests so, or if
          ** the final character in the name is '/'.  */
          u32 mode = pCsr->cds.iExternalAttr >> 16;
          if( !(mode & S_IFDIR) && pCsr->cds.zFile[pCsr->cds.nFile-1]!='/' ){
            sqlite3_result_blob(ctx, "", 0, SQLITE_STATIC);
          }
        }
      }
      break;
    }
    case 6:   /* method */
      sqlite3_result_int(ctx, pCsr->cds.iCompression);
      break;
    case 7:   /* z */
      sqlite3_result_int64(ctx, pCsr->iId);
      break;
  }

  return rc;
................................................................................
  int idxNum, const char *idxStr,
  int argc, sqlite3_value **argv
){
  ZipfileTab *pTab = (ZipfileTab*)cur->pVtab;
  ZipfileCsr *pCsr = (ZipfileCsr*)cur;
  const char *zFile;              /* Zip file to scan */
  int rc = SQLITE_OK;             /* Return Code */


  zipfileResetCursor(pCsr);

  if( pTab->zFile ){
    zFile = pTab->zFile;
  }else if( idxNum==0 ){
    /* Error. This is an eponymous virtual table and the user has not 
    ** supplied a file name. */
    zipfileSetErrmsg(pCsr, "table function zipfile() requires an argument");
    return SQLITE_ERROR;

  }else{
    zFile = (const char*)sqlite3_value_text(argv[0]);
  }

  if( pTab->pWriteFd==0 ){
    pCsr->pFile = fopen(zFile, "rb");
    if( pCsr->pFile==0 ){
      zipfileSetErrmsg(pCsr, "cannot open file: %s", zFile);
      rc = SQLITE_ERROR;
    }else{
      rc = zipfileReadEOCD(pTab, pCsr->pFile, &pCsr->eocd);
      if( rc==SQLITE_OK ){
................................................................................
        }else{
          pCsr->iNextOff = pCsr->eocd.iOffset;
          rc = zipfileNext(cur);
        }
      }
    }
  }else{
    ZipfileEntry e;
    memset(&e, 0, sizeof(e));
    e.pNext = pTab->pFirstEntry;
    pCsr->pCurrent = &e;
    rc = zipfileNext(cur);
    assert( pCsr->pCurrent!=&e );
  }

  return rc;
}

/*
** xBestIndex callback.
................................................................................
    *pp = pNew;
  }
}

static int zipfileLoadDirectory(ZipfileTab *pTab){
  ZipfileEOCD eocd;
  int rc;

  rc = zipfileReadEOCD(pTab, pTab->pWriteFd, &eocd);
  if( rc==SQLITE_OK && eocd.nEntry>0 ){
    int i;
    int iOff = 0;
    u8 *aBuf = sqlite3_malloc(eocd.nSize);
    if( aBuf==0 ){
      rc = SQLITE_NOMEM;
    }else{
      rc = zipfileReadData(
          pTab->pWriteFd, aBuf, eocd.nSize, eocd.iOffset, &pTab->base.zErrMsg
      );
    }



    for(i=0; rc==SQLITE_OK && i<eocd.nEntry; i++){
      u16 nFile;
      u16 nExtra;
      u16 nComment;
      ZipfileEntry *pNew;
      u8 *aRec = &aBuf[iOff];


      nFile = zipfileGetU16(&aRec[ZIPFILE_CDS_NFILE_OFF]);
      nExtra = zipfileGetU16(&aRec[ZIPFILE_CDS_NFILE_OFF+2]);
      nComment = zipfileGetU16(&aRec[ZIPFILE_CDS_NFILE_OFF+4]);

      pNew = sqlite3_malloc(
          sizeof(ZipfileEntry) 
        + nFile+1 
        + ZIPFILE_CDS_FIXED_SZ+nFile+nExtra+nComment
      );
      if( pNew==0 ){
        rc = SQLITE_NOMEM;
      }else{
        memset(pNew, 0, sizeof(ZipfileEntry));
        pNew->zPath = (char*)&pNew[1];
        memcpy(pNew->zPath, &aRec[ZIPFILE_CDS_FIXED_SZ], nFile);
        pNew->zPath[nFile] = '\0';
        pNew->aCdsEntry = (u8*)&pNew->zPath[nFile+1];
        pNew->nCdsEntry = ZIPFILE_CDS_FIXED_SZ+nFile+nExtra+nComment;
        memcpy(pNew->aCdsEntry, aRec, pNew->nCdsEntry);
        zipfileAddEntry(pTab, 0, pNew);
      }

      iOff += ZIPFILE_CDS_FIXED_SZ+nFile+nExtra+nComment;

    }

    sqlite3_free(aBuf);
  }

  return rc;
}

static ZipfileEntry *zipfileNewEntry(
  ZipfileCDS *pCds,               /* Values for fixed size part of CDS */
  const char *zPath,              /* Path for new entry */
  int nPath,                      /* strlen(zPath) */
  u32 mTime                       /* Modification time (or 0) */
){
  u8 *aWrite;
  ZipfileEntry *pNew;
  pCds->nFile = (u16)nPath;
  pCds->nExtra = mTime ? 9 : 0;
  pNew = (ZipfileEntry*)sqlite3_malloc(
    sizeof(ZipfileEntry) + 
    nPath+1 + 
    ZIPFILE_CDS_FIXED_SZ + nPath + pCds->nExtra
  );

  if( pNew ){
    memset(pNew, 0, sizeof(ZipfileEntry));
    pNew->zPath = (char*)&pNew[1];
    pNew->aCdsEntry = (u8*)&pNew->zPath[nPath+1];
    pNew->nCdsEntry = ZIPFILE_CDS_FIXED_SZ + nPath + pCds->nExtra;
    memcpy(pNew->zPath, zPath, nPath+1);





    aWrite = pNew->aCdsEntry;
    zipfileWrite32(aWrite, ZIPFILE_SIGNATURE_CDS);
    zipfileWrite16(aWrite, pCds->iVersionMadeBy);
    zipfileWrite16(aWrite, pCds->iVersionExtract);
    zipfileWrite16(aWrite, pCds->flags);
    zipfileWrite16(aWrite, pCds->iCompression);
    zipfileWrite16(aWrite, pCds->mTime);
    zipfileWrite16(aWrite, pCds->mDate);
    zipfileWrite32(aWrite, pCds->crc32);
    zipfileWrite32(aWrite, pCds->szCompressed);
    zipfileWrite32(aWrite, pCds->szUncompressed);
    zipfileWrite16(aWrite, pCds->nFile);
    zipfileWrite16(aWrite, pCds->nExtra);
    zipfileWrite16(aWrite, pCds->nComment);      assert( pCds->nComment==0 );
    zipfileWrite16(aWrite, pCds->iDiskStart);
    zipfileWrite16(aWrite, pCds->iInternalAttr);
    zipfileWrite32(aWrite, pCds->iExternalAttr);
    zipfileWrite32(aWrite, pCds->iOffset);
    assert( aWrite==&pNew->aCdsEntry[ZIPFILE_CDS_FIXED_SZ] );
    memcpy(aWrite, zPath, nPath);
    if( pCds->nExtra ){
      aWrite += nPath;
      zipfileWrite16(aWrite, ZIPFILE_EXTRA_TIMESTAMP);
      zipfileWrite16(aWrite, 5);
      *aWrite++ = 0x01;
      zipfileWrite32(aWrite, mTime);
    }
  }

  return pNew;
}

static int zipfileAppendEntry(
  ZipfileTab *pTab,
  ZipfileCDS *pCds,
  const char *zPath,              /* Path for new entry */
................................................................................
  int nPath,                      /* strlen(zPath) */
  const u8 *pData,
  int nData,
  u32 mTime
){
  u8 *aBuf = pTab->aBuffer;
  int rc;



  zipfileWrite32(aBuf, ZIPFILE_SIGNATURE_LFH);
  zipfileWrite16(aBuf, pCds->iVersionExtract);
  zipfileWrite16(aBuf, pCds->flags);
  zipfileWrite16(aBuf, pCds->iCompression);
  zipfileWrite16(aBuf, pCds->mTime);
  zipfileWrite16(aBuf, pCds->mDate);
................................................................................
  const char *zPath = 0;          /* Path for new entry */
  int nPath = 0;                  /* strlen(zPath) */
  const u8 *pData = 0;            /* Pointer to buffer containing content */
  int nData = 0;                  /* Size of pData buffer in bytes */
  int iMethod = 0;                /* Compression method for new entry */
  u8 *pFree = 0;                  /* Free this */
  char *zFree = 0;                /* Also free this */
  ZipfileCDS cds;                 /* New Central Directory Structure entry */
  ZipfileEntry *pOld = 0;
  int bIsDir = 0;
  u32 iCrc32 = 0;

  assert( pTab->zFile );
  assert( pTab->pWriteFd );


  if( sqlite3_value_type(apVal[0])!=SQLITE_NULL ){
    const char *zDelete = (const char*)sqlite3_value_text(apVal[0]);
    int nDelete = (int)strlen(zDelete);
    for(pOld=pTab->pFirstEntry; 1; pOld=pOld->pNext){
      if( pOld->bDeleted ) continue;
      if( zipfileComparePath(pOld->zPath, zDelete, nDelete)==0 ){
        pOld->bDeleted = 1;
        break;
      }
      assert( pOld->pNext );
    }
    if( nVal==1 ) return SQLITE_OK;
  }


  /* Check that "sz" and "rawdata" are both NULL: */
  if( sqlite3_value_type(apVal[5])!=SQLITE_NULL
   || sqlite3_value_type(apVal[6])!=SQLITE_NULL
  ){
    rc = SQLITE_CONSTRAINT;
  }

  if( rc==SQLITE_OK ){
    if( sqlite3_value_type(apVal[7])==SQLITE_NULL ){
      /* data=NULL. A directory */
      bIsDir = 1;
    }else{
      /* Value specified for "data", and possibly "method". This must be
      ** a regular file or a symlink. */
      const u8 *aIn = sqlite3_value_blob(apVal[7]);
      int nIn = sqlite3_value_bytes(apVal[7]);
      int bAuto = sqlite3_value_type(apVal[8])==SQLITE_NULL;

      iMethod = sqlite3_value_int(apVal[8]);
      sz = nIn;
      pData = aIn;
      nData = nIn;
      if( iMethod!=0 && iMethod!=8 ){
        rc = SQLITE_CONSTRAINT;
      }else{
        if( bAuto || iMethod ){
          int nCmp;
          rc = zipfileDeflate(pTab, aIn, nIn, &pFree, &nCmp);
          if( rc==SQLITE_OK ){
            if( iMethod || nCmp<nIn ){
              iMethod = 8;
              pData = pFree;
              nData = nCmp;
            }
          }
        }
        iCrc32 = crc32(0, aIn, nIn);
      }
    }
  }

  if( rc==SQLITE_OK ){
    rc = zipfileGetMode(pTab, apVal[3], 
        (bIsDir ? (S_IFDIR + 0755) : (S_IFREG + 0644)), &mode
    );
    if( rc==SQLITE_OK && (bIsDir == ((mode & S_IFDIR)==0)) ){
      /* The "mode" attribute is a directory, but data has been specified.
      ** Or vice-versa - no data but "mode" is a file or symlink.  */
      rc = SQLITE_CONSTRAINT;
    }
  }

  if( rc==SQLITE_OK ){
    zPath = (const char*)sqlite3_value_text(apVal[2]);
    nPath = (int)strlen(zPath);
    if( sqlite3_value_type(apVal[4])==SQLITE_NULL ){
      mTime = (sqlite3_int64)time(0);
    }else{
      mTime = sqlite3_value_int64(apVal[4]);
    }
  }

  if( rc==SQLITE_OK && bIsDir ){
    /* For a directory, check that the last character in the path is a
    ** '/'. This appears to be required for compatibility with info-zip
    ** (the unzip command on unix). It does not create directories
    ** otherwise.  */
    if( zPath[nPath-1]!='/' ){
      zFree = sqlite3_mprintf("%s/", zPath);
      if( zFree==0 ){ rc = SQLITE_NOMEM; }
      zPath = (const char*)zFree;
      nPath++;
    }
  }

  /* Check that we're not inserting a duplicate entry */
  if( rc==SQLITE_OK ){
    ZipfileEntry *p;
    for(p=pTab->pFirstEntry; p; p=p->pNext){
      if( p->bDeleted ) continue;
      if( zipfileComparePath(p->zPath, zPath, nPath)==0 ){
        rc = SQLITE_CONSTRAINT;
        break;
      }
    }
  }

  if( rc==SQLITE_OK ){
    /* Create the new CDS record. */

    memset(&cds, 0, sizeof(cds));


    cds.iVersionMadeBy = ZIPFILE_NEWENTRY_MADEBY;
    cds.iVersionExtract = ZIPFILE_NEWENTRY_REQUIRED;
    cds.flags = ZIPFILE_NEWENTRY_FLAGS;
    cds.iCompression = (u16)iMethod;
    zipfileMtimeToDos(&cds, (u32)mTime);
    cds.crc32 = iCrc32;
    cds.szCompressed = nData;
    cds.szUncompressed = (u32)sz;
    cds.iExternalAttr = (mode<<16);
    cds.iOffset = (u32)pTab->szCurrent;
    pNew = zipfileNewEntry(&cds, zPath, nPath, (u32)mTime);
    if( pNew==0 ){
      rc = SQLITE_NOMEM;
    }else{



      zipfileAddEntry(pTab, pOld, pNew);
    }
  }

  /* Append the new header+file to the archive */

  if( rc==SQLITE_OK ){
    rc = zipfileAppendEntry(pTab, &cds, zPath, nPath, pData, nData, (u32)mTime);






  }

  if( rc!=SQLITE_OK && pOld ){
    pOld->bDeleted = 0;



  }

  sqlite3_free(pFree);
  sqlite3_free(zFree);
  return rc;
}

static int zipfileAppendEOCD(ZipfileTab *pTab, ZipfileEOCD *p){
  u8 *aBuf = pTab->aBuffer;
................................................................................
  zipfileWrite32(aBuf, p->iOffset);
  zipfileWrite16(aBuf, 0);        /* Size of trailing comment in bytes*/

  assert( (aBuf-pTab->aBuffer)==22 );
  return zipfileAppendData(pTab, pTab->aBuffer, (int)(aBuf - pTab->aBuffer));
}

static void zipfileCleanupTransaction(ZipfileTab *pTab){
  ZipfileEntry *pEntry;
  ZipfileEntry *pNext;

  for(pEntry=pTab->pFirstEntry; pEntry; pEntry=pNext){
    pNext = pEntry->pNext;
    sqlite3_free(pEntry);
  }
  pTab->pFirstEntry = 0;
  pTab->pLastEntry = 0;
  fclose(pTab->pWriteFd);
  pTab->pWriteFd = 0;
  pTab->szCurrent = 0;
  pTab->szOrig = 0;
}

static int zipfileBegin(sqlite3_vtab *pVtab){
  ZipfileTab *pTab = (ZipfileTab*)pVtab;
  int rc = SQLITE_OK;

  assert( pTab->pWriteFd==0 );

  /* This table is only writable if a default archive path was specified 
................................................................................

  if( rc!=SQLITE_OK ){
    zipfileCleanupTransaction(pTab);
  }

  return rc;
}


















































static int zipfileCommit(sqlite3_vtab *pVtab){
  ZipfileTab *pTab = (ZipfileTab*)pVtab;
  int rc = SQLITE_OK;
  if( pTab->pWriteFd ){
    i64 iOffset = pTab->szCurrent;
    ZipfileEntry *p;
    ZipfileEOCD eocd;
    int nEntry = 0;

    /* Write out all undeleted entries */
    for(p=pTab->pFirstEntry; rc==SQLITE_OK && p; p=p->pNext){
      if( p->bDeleted ) continue;
      rc = zipfileAppendData(pTab, p->aCdsEntry, p->nCdsEntry);
      nEntry++;
    }

    /* Write out the EOCD record */
    eocd.iDisk = 0;
    eocd.iFirstDisk = 0;
    eocd.nEntry = (u16)nEntry;
................................................................................
){
  ZipfileCsr *pCsr;
  ZipfileTab *pTab = (ZipfileTab*)sqlite3_user_data(context);
  assert( argc>0 );

  pCsr = zipfileFindCursor(pTab, sqlite3_value_int64(argv[0]));
  if( pCsr ){
    ZipfileCDS *p = &pCsr->cds;
    char *zRes = sqlite3_mprintf("{"
        "\"version-made-by\" : %u, "
        "\"version-to-extract\" : %u, "
        "\"flags\" : %u, "
        "\"compression\" : %u, "
        "\"time\" : %u, "
        "\"date\" : %u, "

  u32 szUncompressed;
  u16 nFile;
  u16 nExtra;
};

typedef struct ZipfileEntry ZipfileEntry;
struct ZipfileEntry {
  ZipfileCDS cds;            /* Parsed CDS record */
  u32 mUnixTime;             /* Modification time, in UNIX format */
  u8 *aExtra;                /* cds.nExtra+cds.nComment bytes of extra data */

  ZipfileEntry *pNext;       /* Next element in in-memory CDS */
};

/* 
** Cursor type for recursively iterating through a directory structure.
*/
typedef struct ZipfileCsr ZipfileCsr;
struct ZipfileCsr {
  sqlite3_vtab_cursor base;  /* Base class - must be first */
  i64 iId;                   /* Cursor ID */
  u8 bEof;                   /* True when at EOF */
  u8 bNoop;                  /* If next xNext() call is no-op */

  /* Used outside of write transactions */
  FILE *pFile;               /* Zip file */
  i64 iNextOff;              /* Offset of next record in central directory */
  ZipfileEOCD eocd;          /* Parse of central directory record */


  ZipfileEntry *pCurrent;    /* Current entry */


  ZipfileLFH lfh;            /* Local File Header for current entry */
  i64 iDataOff;              /* Offset in zipfile to data */


  ZipfileCsr *pCsrNext;      /* Next cursor on same virtual table */
};

/*
** Possible values for ZipfileCsr.eType. Set in zipfileFilter().
*/
#define ZIPFILE_CSR_LIST 1        /* Cursor reads from ZipfileTab.pFirstEntry */
#define ZIPFILE_CSR_FILE 2        /* Cursor reads from file on disk */

/*
** Values for ZipfileCsr.flags.
*/
#define ZIPFILE_NOOP_NEXT   0x0002     /* Next xNext() is a no-op */

typedef struct ZipfileTab ZipfileTab;
struct ZipfileTab {
  sqlite3_vtab base;         /* Base class - must be first */
  char *zFile;               /* Zip file this table accesses (may be NULL) */
  u8 *aBuffer;               /* Temporary buffer used for various tasks */

................................................................................
      memcpy(pNew->zFile, zFile, nFile);
      zipfileDequote(pNew->zFile);
    }
  }
  *ppVtab = (sqlite3_vtab*)pNew;
  return rc;
}

static void zipfileEntryFree(ZipfileEntry *p){
  if( p ){
    sqlite3_free(p->cds.zFile);
    sqlite3_free(p);
  }
}

static void zipfileCleanupTransaction(ZipfileTab *pTab){
  ZipfileEntry *pEntry;
  ZipfileEntry *pNext;

  if( pTab->pWriteFd ){
    fclose(pTab->pWriteFd);
    pTab->pWriteFd = 0;
  }
  for(pEntry=pTab->pFirstEntry; pEntry; pEntry=pNext){
    pNext = pEntry->pNext;
    zipfileEntryFree(pEntry);
  }
  pTab->pFirstEntry = 0;
  pTab->pLastEntry = 0;
  pTab->szCurrent = 0;
  pTab->szOrig = 0;
}

/*
** This method is the destructor for zipfile vtab objects.
*/
static int zipfileDisconnect(sqlite3_vtab *pVtab){
  zipfileCleanupTransaction((ZipfileTab*)pVtab);
  sqlite3_free(pVtab);
  return SQLITE_OK;
}

/*
** Constructor for a new ZipfileCsr object.
*/
................................................................................
}

/*
** Reset a cursor back to the state it was in when first returned
** by zipfileOpen().
*/
static void zipfileResetCursor(ZipfileCsr *pCsr){


  pCsr->bEof = 0;
  if( pCsr->pFile ){
    fclose(pCsr->pFile);
    pCsr->pFile = 0;
    zipfileEntryFree(pCsr->pCurrent);
    pCsr->pCurrent = 0;
  }
}

/*
** Destructor for an ZipfileCsr.
*/
static int zipfileClose(sqlite3_vtab_cursor *cur){
................................................................................
    assert( aRead==&aBuf[ZIPFILE_CDS_FIXED_SZ] );
  }

  return rc;
}

/*











































** The general format of an extra field is:
**
**   Header ID    2 bytes
**   Data Size    2 bytes
**   Data         N bytes

*/


static int zipfileScanExtra(u8 *aExtra, int nExtra, u32 *pmTime){
  int ret = 0;
  u8 *p = aExtra;
  u8 *pEnd = &aExtra[nExtra];

  while( p<pEnd ){
    u16 id = zipfileRead16(p);
    u16 nByte = zipfileRead16(p);

    switch( id ){
      case ZIPFILE_EXTRA_TIMESTAMP: {
        u8 b = p[0];
        if( b & 0x01 ){     /* 0x01 -> modtime is present */
          *pmTime = zipfileGetU32(&p[1]);

          ret = 1;
        }
        break;
      }
    }

    p += nByte;
  }
  return ret;
}

/*
** "Standard" MS-DOS time format:
**
**   File modification time:
**     Bits 00-04: seconds divided by 2
**     Bits 05-10: minute
**     Bits 11-15: hour
**   File modification date:
**     Bits 00-04: day
**     Bits 05-08: month (1-12)
**     Bits 09-15: years from 1980 
*/
static time_t zipfileMtime(ZipfileCDS *pCDS){
  struct tm t;
  memset(&t, 0, sizeof(t));
  t.tm_sec = (pCDS->mTime & 0x1F)*2;
  t.tm_min = (pCDS->mTime >> 5) & 0x2F;
  t.tm_hour = (pCDS->mTime >> 11) & 0x1F;

  t.tm_mday = (pCDS->mDate & 0x1F);
  t.tm_mon = ((pCDS->mDate >> 5) & 0x0F) - 1;
  t.tm_year = 80 + ((pCDS->mDate >> 9) & 0x7F);

  return mktime(&t);
}

/*
** Read a Zip archive CDS header from offset iOff of file pFile. Return
** SQLITE_OK if successful, or an SQLite error code otherwise.
*/
static int zipfileGetEntry(
  ZipfileTab *pTab,               /* Store any error message here */
  FILE *pFile,
  i64 iOff,
  ZipfileEntry **ppEntry
){
  u8 *aRead = pTab->aBuffer;
  char **pzErr = &pTab->base.zErrMsg;
  int rc;

  rc = zipfileReadData(pFile, aRead, ZIPFILE_CDS_FIXED_SZ, iOff, pzErr);
  if( rc==SQLITE_OK ){
    if( rc!=SQLITE_OK ){
      *pzErr = sqlite3_mprintf("failed to read CDS at offset %lld", iOff);
    }else{
      ZipfileEntry *pNew;

      int nFile = zipfileGetU16(&aRead[ZIPFILE_CDS_NFILE_OFF]);
      int nExtra = zipfileGetU16(&aRead[ZIPFILE_CDS_NFILE_OFF+2]);
      nExtra += zipfileGetU16(&aRead[ZIPFILE_CDS_NFILE_OFF+4]);

      pNew = (ZipfileEntry*)sqlite3_malloc(sizeof(ZipfileEntry) + nExtra);
      if( pNew==0 ){
        rc = SQLITE_NOMEM;
      }else{
        memset(pNew, 0, sizeof(ZipfileEntry));
        rc = zipfileReadCDS(aRead, &pNew->cds);
        if( rc!=SQLITE_OK ){
          *pzErr = sqlite3_mprintf("failed to read CDS at offset %lld", iOff);
        }else{
          rc = zipfileReadData(
              pFile, aRead, nExtra+nFile, iOff+ZIPFILE_CDS_FIXED_SZ, pzErr
          );
        }
      }

      if( rc==SQLITE_OK ){
        u32 *pt = &pNew->mUnixTime;
        pNew->cds.zFile = sqlite3_mprintf("%.*s", nFile, aRead); 
        if( pNew->cds.zFile==0 ){
          rc = SQLITE_NOMEM;
        }else if( 0==zipfileScanExtra(&aRead[nFile], pNew->cds.nExtra, pt) ){
          pNew->mUnixTime = zipfileMtime(&pNew->cds);
        }
      }

      if( rc!=SQLITE_OK ){
        zipfileEntryFree(pNew);
      }else{
        *ppEntry = pNew;
      }
    }
  }

  return rc;
}

static FILE *zipfileGetFd(ZipfileCsr *pCsr){
................................................................................
  return rc;
}

static int zipfileCsrReadLFH(ZipfileCsr *pCsr){
  FILE *pFile = zipfileGetFd(pCsr);
  char **pzErr = &pCsr->base.pVtab->zErrMsg;
  u8 *aRead = zipfileCsrBuffer(pCsr);
  ZipfileCDS *pCDS = &pCsr->pCurrent->cds;
  int rc = zipfileReadLFH(pFile, pCDS->iOffset, aRead, &pCsr->lfh, pzErr);
  pCsr->iDataOff =  pCDS->iOffset + ZIPFILE_LFH_FIXED_SZ;
  pCsr->iDataOff += pCsr->lfh.nFile+pCsr->lfh.nExtra;
  return rc;
}


/*
** Advance an ZipfileCsr to its next row of output.
*/
static int zipfileNext(sqlite3_vtab_cursor *cur){
  ZipfileCsr *pCsr = (ZipfileCsr*)cur;
  int rc = SQLITE_OK;


  if( pCsr->pFile ){
    i64 iEof = pCsr->eocd.iOffset + pCsr->eocd.nSize;
    zipfileEntryFree(pCsr->pCurrent);
    pCsr->pCurrent = 0;
    if( pCsr->iNextOff>=iEof ){
      pCsr->bEof = 1;
    }else{
      ZipfileEntry *p = 0;
      ZipfileTab *pTab = (ZipfileTab*)(cur->pVtab);
      rc = zipfileGetEntry(pTab, pCsr->pFile, pCsr->iNextOff, &p);
      if( rc==SQLITE_OK ){
        pCsr->iNextOff += ZIPFILE_CDS_FIXED_SZ;
        pCsr->iNextOff += (int)p->cds.nExtra + p->cds.nFile + p->cds.nComment;
      }
      pCsr->pCurrent = p;
    }
  }else{


    if( !pCsr->bNoop ){
      pCsr->pCurrent = pCsr->pCurrent->pNext;

    }
    if( pCsr->pCurrent==0 ){
      pCsr->bEof = 1;
    }
  }

  pCsr->bNoop = 0;

  if( rc==SQLITE_OK && pCsr->bEof==0 ){
    rc = zipfileCsrReadLFH(pCsr);

  }

  return rc;
}



























static void zipfileMtimeToDos(ZipfileCDS *pCds, u32 mTime){
  time_t t = (time_t)mTime;
  struct tm res;

#if !defined(_WIN32) && !defined(WIN32)
  localtime_r(&t, &res);
#else
................................................................................
*/
static int zipfileColumn(
  sqlite3_vtab_cursor *cur,   /* The cursor */
  sqlite3_context *ctx,       /* First argument to sqlite3_result_...() */
  int i                       /* Which column to return */
){
  ZipfileCsr *pCsr = (ZipfileCsr*)cur;
  ZipfileCDS *pCDS = &pCsr->pCurrent->cds;
  int rc = SQLITE_OK;
  switch( i ){
    case 0:   /* name */
      sqlite3_result_text(ctx, pCDS->zFile, -1, SQLITE_TRANSIENT);
      break;
    case 1:   /* mode */
      /* TODO: Whether or not the following is correct surely depends on
      ** the platform on which the archive was created.  */
      sqlite3_result_int(ctx, pCDS->iExternalAttr >> 16);
      break;
    case 2: { /* mtime */

      sqlite3_result_int64(ctx, pCsr->pCurrent->mUnixTime);



      break;
    }
    case 3: { /* sz */
      if( sqlite3_vtab_nochange(ctx)==0 ){
        sqlite3_result_int64(ctx, pCDS->szUncompressed);
      }
      break;
    }
    case 4:   /* rawdata */
      if( sqlite3_vtab_nochange(ctx) ) break;
    case 5: { /* data */
      if( i==4 || pCDS->iCompression==0 || pCDS->iCompression==8 ){
        int sz = pCDS->szCompressed;
        int szFinal = pCDS->szUncompressed;
        if( szFinal>0 ){
          u8 *aBuf = sqlite3_malloc(sz);
          if( aBuf==0 ){
            rc = SQLITE_NOMEM;
          }else{
            FILE *pFile = zipfileGetFd(pCsr);
            rc = zipfileReadData(pFile, aBuf, sz, pCsr->iDataOff,
                &pCsr->base.pVtab->zErrMsg
            );
          }
          if( rc==SQLITE_OK ){
            if( i==5 && pCDS->iCompression ){
              zipfileInflate(ctx, aBuf, sz, szFinal);
            }else{
              sqlite3_result_blob(ctx, aBuf, sz, SQLITE_TRANSIENT);
            }
            sqlite3_free(aBuf);
          }
        }else{
          /* Figure out if this is a directory or a zero-sized file. Consider
          ** it to be a directory either if the mode suggests so, or if
          ** the final character in the name is '/'.  */
          u32 mode = pCDS->iExternalAttr >> 16;
          if( !(mode & S_IFDIR) && pCDS->zFile[pCDS->nFile-1]!='/' ){
            sqlite3_result_blob(ctx, "", 0, SQLITE_STATIC);
          }
        }
      }
      break;
    }
    case 6:   /* method */
      sqlite3_result_int(ctx, pCDS->iCompression);
      break;
    case 7:   /* z */
      sqlite3_result_int64(ctx, pCsr->iId);
      break;
  }

  return rc;
................................................................................
  int idxNum, const char *idxStr,
  int argc, sqlite3_value **argv
){
  ZipfileTab *pTab = (ZipfileTab*)cur->pVtab;
  ZipfileCsr *pCsr = (ZipfileCsr*)cur;
  const char *zFile;              /* Zip file to scan */
  int rc = SQLITE_OK;             /* Return Code */
  int bInMemory = 0;              /* True for an in-memory zipfile */

  zipfileResetCursor(pCsr);

  if( pTab->zFile ){
    zFile = pTab->zFile;
  }else if( idxNum==0 ){
    /* Error. This is an eponymous virtual table and the user has not 
    ** supplied a file name. */
    zipfileSetErrmsg(pCsr, "table function zipfile() requires an argument");
    return SQLITE_ERROR;
  }else if( sqlite3_value_type(argv[0])==SQLITE_BLOB ){
  }else{
    zFile = (const char*)sqlite3_value_text(argv[0]);
  }

  if( 0==pTab->pWriteFd && 0==bInMemory ){
    pCsr->pFile = fopen(zFile, "rb");
    if( pCsr->pFile==0 ){
      zipfileSetErrmsg(pCsr, "cannot open file: %s", zFile);
      rc = SQLITE_ERROR;
    }else{
      rc = zipfileReadEOCD(pTab, pCsr->pFile, &pCsr->eocd);
      if( rc==SQLITE_OK ){
................................................................................
        }else{
          pCsr->iNextOff = pCsr->eocd.iOffset;
          rc = zipfileNext(cur);
        }
      }
    }
  }else{
    pCsr->bNoop = 1;

    pCsr->pCurrent = pTab->pFirstEntry;

    rc = zipfileNext(cur);

  }

  return rc;
}

/*
** xBestIndex callback.
................................................................................
    *pp = pNew;
  }
}

static int zipfileLoadDirectory(ZipfileTab *pTab){
  ZipfileEOCD eocd;
  int rc;



  int i;
  i64 iOff;









  rc = zipfileReadEOCD(pTab, pTab->pWriteFd, &eocd);
  iOff = eocd.iOffset;
  for(i=0; rc==SQLITE_OK && i<eocd.nEntry; i++){



    ZipfileEntry *pNew = 0;

    rc = zipfileGetEntry(pTab, pTab->pWriteFd, iOff, &pNew);











    if( rc==SQLITE_OK ){








      zipfileAddEntry(pTab, 0, pNew);


      iOff += ZIPFILE_CDS_FIXED_SZ;
      iOff += (int)pNew->cds.nExtra + pNew->cds.nFile + pNew->cds.nComment;
    }
  }



  return rc;
}

static ZipfileEntry *zipfileNewEntry(const char *zPath){






  ZipfileEntry *pNew;



  pNew = sqlite3_malloc(sizeof(ZipfileEntry));




  if( pNew ){
    memset(pNew, 0, sizeof(ZipfileEntry));




    pNew->cds.zFile = sqlite3_mprintf("%s", zPath);
    if( pNew->cds.zFile==0 ){
      sqlite3_free(pNew);
      pNew = 0;
    }


























  }


  return pNew;
}

static int zipfileAppendEntry(
  ZipfileTab *pTab,
  ZipfileCDS *pCds,
  const char *zPath,              /* Path for new entry */
................................................................................
  int nPath,                      /* strlen(zPath) */
  const u8 *pData,
  int nData,
  u32 mTime
){
  u8 *aBuf = pTab->aBuffer;
  int rc;

  pCds->nExtra = 9;

  zipfileWrite32(aBuf, ZIPFILE_SIGNATURE_LFH);
  zipfileWrite16(aBuf, pCds->iVersionExtract);
  zipfileWrite16(aBuf, pCds->flags);
  zipfileWrite16(aBuf, pCds->iCompression);
  zipfileWrite16(aBuf, pCds->mTime);
  zipfileWrite16(aBuf, pCds->mDate);
................................................................................
  const char *zPath = 0;          /* Path for new entry */
  int nPath = 0;                  /* strlen(zPath) */
  const u8 *pData = 0;            /* Pointer to buffer containing content */
  int nData = 0;                  /* Size of pData buffer in bytes */
  int iMethod = 0;                /* Compression method for new entry */
  u8 *pFree = 0;                  /* Free this */
  char *zFree = 0;                /* Also free this */

  ZipfileEntry *pOld = 0;
  int bIsDir = 0;
  u32 iCrc32 = 0;

  assert( pTab->zFile );
  assert( pTab->pWriteFd );

  /* If this is a DELETE or UPDATE, find the archive entry to delete. */
  if( sqlite3_value_type(apVal[0])!=SQLITE_NULL ){
    const char *zDelete = (const char*)sqlite3_value_text(apVal[0]);
    int nDelete = (int)strlen(zDelete);
    for(pOld=pTab->pFirstEntry; 1; pOld=pOld->pNext){

      if( zipfileComparePath(pOld->cds.zFile, zDelete, nDelete)==0 ){

        break;
      }
      assert( pOld->pNext );
    }

  }

  if( nVal>1 ){
    /* Check that "sz" and "rawdata" are both NULL: */
    if( sqlite3_value_type(apVal[5])!=SQLITE_NULL
     || sqlite3_value_type(apVal[6])!=SQLITE_NULL
    ){
      rc = SQLITE_CONSTRAINT;
    }

    if( rc==SQLITE_OK ){
      if( sqlite3_value_type(apVal[7])==SQLITE_NULL ){
        /* data=NULL. A directory */
        bIsDir = 1;
      }else{
        /* Value specified for "data", and possibly "method". This must be
        ** a regular file or a symlink. */
        const u8 *aIn = sqlite3_value_blob(apVal[7]);
        int nIn = sqlite3_value_bytes(apVal[7]);
        int bAuto = sqlite3_value_type(apVal[8])==SQLITE_NULL;

        iMethod = sqlite3_value_int(apVal[8]);
        sz = nIn;
        pData = aIn;
        nData = nIn;
        if( iMethod!=0 && iMethod!=8 ){
          rc = SQLITE_CONSTRAINT;
        }else{
          if( bAuto || iMethod ){
            int nCmp;
            rc = zipfileDeflate(pTab, aIn, nIn, &pFree, &nCmp);
            if( rc==SQLITE_OK ){
              if( iMethod || nCmp<nIn ){
                iMethod = 8;
                pData = pFree;
                nData = nCmp;
              }
            }
          }
          iCrc32 = crc32(0, aIn, nIn);
        }
      }
    }

    if( rc==SQLITE_OK ){
      rc = zipfileGetMode(pTab, apVal[3], 
          (bIsDir ? (S_IFDIR + 0755) : (S_IFREG + 0644)), &mode
      );
      if( rc==SQLITE_OK && (bIsDir == ((mode & S_IFDIR)==0)) ){
        /* The "mode" attribute is a directory, but data has been specified.
        ** Or vice-versa - no data but "mode" is a file or symlink.  */
        rc = SQLITE_CONSTRAINT;
      }
    }

    if( rc==SQLITE_OK ){
      zPath = (const char*)sqlite3_value_text(apVal[2]);
      nPath = (int)strlen(zPath);
      if( sqlite3_value_type(apVal[4])==SQLITE_NULL ){
        mTime = (sqlite3_int64)time(0);
      }else{
        mTime = sqlite3_value_int64(apVal[4]);
      }
    }

    if( rc==SQLITE_OK && bIsDir ){
      /* For a directory, check that the last character in the path is a
      ** '/'. This appears to be required for compatibility with info-zip
      ** (the unzip command on unix). It does not create directories
      ** otherwise.  */
      if( zPath[nPath-1]!='/' ){
        zFree = sqlite3_mprintf("%s/", zPath);
        if( zFree==0 ){ rc = SQLITE_NOMEM; }
        zPath = (const char*)zFree;
        nPath++;
      }
    }

    /* Check that we're not inserting a duplicate entry */
    if( pOld==0 && rc==SQLITE_OK ){
      ZipfileEntry *p;
      for(p=pTab->pFirstEntry; p; p=p->pNext){

        if( zipfileComparePath(p->cds.zFile, zPath, nPath)==0 ){
          rc = SQLITE_CONSTRAINT;
          break;
        }
      }
    }

    if( rc==SQLITE_OK ){
      /* Create the new CDS record. */
      pNew = zipfileNewEntry(zPath);
      if( pNew==0 ){
        rc = SQLITE_NOMEM;
      }else{
        pNew->cds.iVersionMadeBy = ZIPFILE_NEWENTRY_MADEBY;
        pNew->cds.iVersionExtract = ZIPFILE_NEWENTRY_REQUIRED;
        pNew->cds.flags = ZIPFILE_NEWENTRY_FLAGS;
        pNew->cds.iCompression = (u16)iMethod;
        zipfileMtimeToDos(&pNew->cds, (u32)mTime);
        pNew->cds.crc32 = iCrc32;
        pNew->cds.szCompressed = nData;
        pNew->cds.szUncompressed = (u32)sz;
        pNew->cds.iExternalAttr = (mode<<16);
        pNew->cds.iOffset = (u32)pTab->szCurrent;


        pNew->cds.nFile = nPath;
        pNew->mUnixTime = (u32)mTime;
        rc = zipfileAppendEntry(
            pTab, &pNew->cds, zPath, nPath, pData, nData, pNew->mUnixTime
        );
        zipfileAddEntry(pTab, pOld, pNew);
      }
    }
  }


  if( rc==SQLITE_OK && pOld ){

    ZipfileEntry **pp;
    ZipfileCsr *pCsr;
    for(pCsr=pTab->pCsrList; pCsr; pCsr=pCsr->pCsrNext){
      if( pCsr->pCurrent==pOld ){
        pCsr->pCurrent = pOld->pNext;
        pCsr->bNoop = 1;
      }
    }


    for(pp=&pTab->pFirstEntry; (*pp)!=pOld; pp=&((*pp)->pNext));
    *pp = (*pp)->pNext;
    zipfileEntryFree(pOld);
  }

  sqlite3_free(pFree);
  sqlite3_free(zFree);
  return rc;
}

static int zipfileAppendEOCD(ZipfileTab *pTab, ZipfileEOCD *p){
  u8 *aBuf = pTab->aBuffer;
................................................................................
  zipfileWrite32(aBuf, p->iOffset);
  zipfileWrite16(aBuf, 0);        /* Size of trailing comment in bytes*/

  assert( (aBuf-pTab->aBuffer)==22 );
  return zipfileAppendData(pTab, pTab->aBuffer, (int)(aBuf - pTab->aBuffer));
}

















static int zipfileBegin(sqlite3_vtab *pVtab){
  ZipfileTab *pTab = (ZipfileTab*)pVtab;
  int rc = SQLITE_OK;

  assert( pTab->pWriteFd==0 );

  /* This table is only writable if a default archive path was specified 
................................................................................

  if( rc!=SQLITE_OK ){
    zipfileCleanupTransaction(pTab);
  }

  return rc;
}

/*
** Serialize the CDS structure into buffer aBuf[]. Return the number
** of bytes written.
*/
static int zipfileSerializeCDS(ZipfileEntry *pEntry, u8 *aBuf){
  u8 *a = aBuf;
  ZipfileCDS *pCDS = &pEntry->cds;

  if( pEntry->aExtra==0 ){
    pCDS->nExtra = 9;
  }

  zipfileWrite32(a, ZIPFILE_SIGNATURE_CDS);
  zipfileWrite16(a, pCDS->iVersionMadeBy);
  zipfileWrite16(a, pCDS->iVersionExtract);
  zipfileWrite16(a, pCDS->flags);
  zipfileWrite16(a, pCDS->iCompression);
  zipfileWrite16(a, pCDS->mTime);
  zipfileWrite16(a, pCDS->mDate);
  zipfileWrite32(a, pCDS->crc32);
  zipfileWrite32(a, pCDS->szCompressed);
  zipfileWrite32(a, pCDS->szUncompressed);
  assert( a==&aBuf[ZIPFILE_CDS_NFILE_OFF] );
  zipfileWrite16(a, pCDS->nFile);
  zipfileWrite16(a, pCDS->nExtra);
  zipfileWrite16(a, pCDS->nComment);
  zipfileWrite16(a, pCDS->iDiskStart);
  zipfileWrite16(a, pCDS->iInternalAttr);
  zipfileWrite32(a, pCDS->iExternalAttr);
  zipfileWrite32(a, pCDS->iOffset);

  memcpy(a, pCDS->zFile, pCDS->nFile);
  a += pCDS->nFile;

  if( pEntry->aExtra ){
    int n = (int)pCDS->nExtra + (int)pCDS->nComment;
    memcpy(a, pEntry->aExtra, n);
    a += n;
  }else{
    assert( pCDS->nExtra==9 );
    zipfileWrite16(a, ZIPFILE_EXTRA_TIMESTAMP);
    zipfileWrite16(a, 5);
    *a++ = 0x01;
    zipfileWrite32(a, pEntry->mUnixTime);
  }

  return a-aBuf;
}

static int zipfileCommit(sqlite3_vtab *pVtab){
  ZipfileTab *pTab = (ZipfileTab*)pVtab;
  int rc = SQLITE_OK;
  if( pTab->pWriteFd ){
    i64 iOffset = pTab->szCurrent;
    ZipfileEntry *p;
    ZipfileEOCD eocd;
    int nEntry = 0;

    /* Write out all entries */
    for(p=pTab->pFirstEntry; rc==SQLITE_OK && p; p=p->pNext){
      int n = zipfileSerializeCDS(p, pTab->aBuffer);
      rc = zipfileAppendData(pTab, pTab->aBuffer, n);
      nEntry++;
    }

    /* Write out the EOCD record */
    eocd.iDisk = 0;
    eocd.iFirstDisk = 0;
    eocd.nEntry = (u16)nEntry;
................................................................................
){
  ZipfileCsr *pCsr;
  ZipfileTab *pTab = (ZipfileTab*)sqlite3_user_data(context);
  assert( argc>0 );

  pCsr = zipfileFindCursor(pTab, sqlite3_value_int64(argv[0]));
  if( pCsr ){
    ZipfileCDS *p = &pCsr->pCurrent->cds;
    char *zRes = sqlite3_mprintf("{"
        "\"version-made-by\" : %u, "
        "\"version-to-extract\" : %u, "
        "\"flags\" : %u, "
        "\"compression\" : %u, "
        "\"time\" : %u, "
        "\"date\" : %u, "