SQLite

  int bEof;                  /* True when at EOF */
  i64 iNextOff;              /* Offset of next record in central directory */
  ZipfileEOCD eocd;          /* Parse of central directory record */
  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) */
};

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

typedef struct ZipfileEntry ZipfileEntry;
struct ZipfileEntry {
  char *zPath;               /* Path of zipfile entry */
  i64 iRowid;                /* Rowid for this value if queried */
  u8 *aCdsEntry;             /* Buffer containing entire CDS entry */
  int nCdsEntry;             /* Size of buffer aCdsEntry[] in bytes */
  ZipfileEntry *pNext;       /* Next element in in-memory CDS */
};

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 */

  /* The following are used by write transactions only */
  ZipfileEntry *pFirstEntry; /* Linked list of all files (if pWriteFd!=0) */
  ZipfileEntry *pLastEntry;  /* Last element in pFirstEntry list */
  FILE *pWriteFd;            /* File handle open on zip archive */
  i64 szCurrent;             /* Current size of zip archive */
  i64 szOrig;                /* Size of archive at start of transaction */
};

static void zipfileDequote(char *zIn){
  char q = zIn[0];

  }else{
    pIdxInfo->estimatedCost = (double)(((sqlite3_int64)1) << 50);
    pIdxInfo->idxNum = 0;
  }

  return SQLITE_OK;
}

/*
** Add object pNew to the end of the linked list that begins at
** ZipfileTab.pFirstEntry and ends with pLastEntry.
*/
static void zipfileAddEntry(ZipfileTab *pTab, ZipfileEntry *pNew){
  assert( (pTab->pFirstEntry==0)==(pTab->pLastEntry==0) );
  assert( pNew->pNext==0 );
  if( pTab->pFirstEntry==0 ){
    pTab->pFirstEntry = pTab->pLastEntry = pNew;
  }else{
    assert( pTab->pLastEntry->pNext==0 );
    pTab->pLastEntry->pNext = pNew;
    pTab->pLastEntry = pNew;
  }
}

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

  rc = zipfileReadEOCD(pTab, pTab->pWriteFd, &eocd);
  if( rc==SQLITE_OK ){

        rc = SQLITE_NOMEM;
      }else{
        pNew->zPath = (char*)&pNew[1];
        memcpy(pNew->zPath, &aBuf[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;
        pNew->pNext = 0;
        memcpy(pNew->aCdsEntry, aRec, pNew->nCdsEntry);
        zipfileAddEntry(pTab, pNew);


      }

      iOff += ZIPFILE_CDS_FIXED_SZ+nFile+nExtra+nComment;
    }

    sqlite3_free(aBuf);
  }else if( rc==SQLITE_EMPTY ){

    ZIPFILE_CDS_FIXED_SZ + nPath + pCds->nExtra
  );

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

    cds.szUncompressed = sz;
    cds.iExternalAttr = (mode<<16);
    cds.iOffset = pTab->szCurrent;
    pNew = zipfileNewEntry(&cds, zPath, nPath, (u32)mTime);
    if( pNew==0 ){
      rc = SQLITE_NOMEM;
    }else{

      zipfileAddEntry(pTab, pNew);
    }
  }

  /* Append the new header+file to the archive */
  if( rc==SQLITE_OK ){
    rc = zipfileAppendEntry(pTab, &cds, zPath, nPath, pData, nData, (u32)mTime);
  }

  return zipfileAppendData(pTab, pTab->aBuffer, 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){
  return SQLITE_OK;
}

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){
      rc = zipfileAppendData(pTab, p->aCdsEntry, p->nCdsEntry);
      nEntry++;
    }

    /* Write out the EOCD record */
    eocd.iDisk = 0;
    eocd.iFirstDisk = 0;
    eocd.nEntry = nEntry;

  INSERT INTO zz VALUES('f.txt', '-rw-r--r--', 1000000000, 5, 'abcde', 0);
  INSERT INTO zz VALUES('g.txt', '-rw-r--r--', 1000000002, 5, '12345', 0);
}

do_execsql_test 1.2 {
  SELECT name, mtime, data FROM zipfile('test.zip');
} {
  f.txt 1000000000 abcde 
  g.txt 1000000002 12345
}

do_execsql_test 1.3 {
  INSERT INTO zz VALUES('h.txt', 
    '-rw-r--r--', 1000000004, 20, 'aaaaaaaaaabbbbbbbbbb', NULL
  );
}

do_execsql_test 1.4 {
  SELECT name, mtime, zipfile_uncompress(data, sz, method), method
  FROM zipfile('test.zip');
} {

  f.txt 1000000000 abcde 0
  g.txt 1000000002 12345 0
  h.txt 1000000004 aaaaaaaaaabbbbbbbbbb 8
}

finish_test