** Variables in which to accumulate a growing ZIP archive.
*/
static Blob body;    /* The body of the ZIP archive */
static Blob toc;     /* The table of contents */
static int nEntry;   /* Number of files */
static int dosTime;  /* DOS-format time */
static int dosDate;  /* DOS-format date */
static int unixTime; /* Seconds since 1970 */
static int nDir;     /* Number of entries in azDir[] */
static char **azDir; /* Directory names already added to the archive */

/*
** Initialize a new ZIP archive.
*/
void zip_open(void){
  blob_zero(&body);
  blob_zero(&toc);
  nEntry = 0;
  dosTime = 0;
  dosDate = 0;
  unixTime = 0;
}

/*
** Set the date and time values from an ISO8601 date string.
*/
void zip_set_timedate_from_str(const char *zDate){
  int y, m, d;

/*
** Set the date and time from a julian day number.
*/
void zip_set_timedate(double rDate){
  char *zDate = db_text(0, "SELECT datetime(%.17g)", rDate);
  zip_set_timedate_from_str(zDate);
  free(zDate);
  unixTime = (rDate - 2440587.5)*86400.0;
}

/*
** If the given filename includes one or more directory entries, make
** sure the directories are already in the archive.  If they are not
** in the archive, add them.
*/
void zip_add_folders(char *zName){
  int i, c;
  int j;
  for(i=0; zName[i]; i++){
    if( zName[i]=='/' ){
      c = zName[i+1];
      zName[i+1] = 0;
      for(j=0; j<nDir; j++){
        if( strcmp(zName, azDir[j])==0 ) break;
      }
      if( j>=nDir ){
        nDir++;
        azDir = realloc(azDir, nDir);
        azDir[j] = sqlite3_mprintf("%s", zName);
        zip_add_file(zName, 0);
      }
      zName[i+1] = c;
    }
  }
}

/*
** Append a single file to a growing ZIP archive.
**
** pFile is the file to be appended.  zName is the name
** that the file should be saved as.
*/
void zip_add_file(const char *zName, const Blob *pFile){
  z_stream stream;
  int nameLen;
  int skip;
  int toOut;
  int iStart;
  int iCRC = 0;
  int nByte = 0;
  int nByteCompr = 0;
  int nBlob;                 /* Size of the blob */
  int iMethod;               /* Compression method. */
  int iMode = 0644;          /* Access permissions */
  char *z;
  char zHdr[30];
  char zExTime[13];
  char zBuf[100];
  char zOutBuf[100000];

  /* Fill in as much of the header as we know.
  */
  nBlob = pFile ? blob_size(pFile) : 0;
  if( nBlob>0 ){
    iMethod = 8;
    iMode = 0100644;
  }else{
    iMethod = 0;
    iMode = 040755;
  }
  nameLen = strlen(zName);
  memset(zHdr, 0, sizeof(zHdr));
  put32(&zHdr[0], 0x04034b50);
  put16(&zHdr[4], 0x000a);
  put16(&zHdr[6], 0);
  put16(&zHdr[8], iMethod);
  put16(&zHdr[10], dosTime);
  put16(&zHdr[12], dosDate);
  put16(&zHdr[26], nameLen);
  put16(&zHdr[28], 13);
  
  put16(&zExTime[0], 0x5455);
  put16(&zExTime[2], 9);
  zExTime[4] = 3;
  put32(&zExTime[5], unixTime);
  put32(&zExTime[9], unixTime);
  

  /* Write the header and filename.
  */
  iStart = blob_size(&body);
  blob_append(&body, zHdr, 30);
  blob_append(&body, zName, nameLen);
  blob_append(&body, zExTime, 13);

  if( nBlob>0 ){
    /* The first two bytes that come out of the deflate compressor are
    ** some kind of header that ZIP does not use.  So skip the first two
    ** output bytes.
    */
    skip = 2;
  
    /* Write the compressed file.  Compute the CRC as we progress.
    */
    stream.zalloc = (alloc_func)0;
    stream.zfree = (free_func)0;
    stream.opaque = 0;
    stream.avail_in = blob_size(pFile);
    stream.next_in = (unsigned char*)blob_buffer(pFile);
    stream.avail_out = sizeof(zOutBuf);
    stream.next_out = (unsigned char*)zOutBuf;
    deflateInit(&stream, 9);
    iCRC = crc32(0, stream.next_in, stream.avail_in);
    while( stream.avail_in>0 ){
      deflate(&stream, 0);
      toOut = sizeof(zOutBuf) - stream.avail_out;
      if( toOut>skip ){
        blob_append(&body, &zOutBuf[skip], toOut - skip);
        skip = 0;
      }else{
        skip -= toOut;
      }
      stream.avail_out = sizeof(zOutBuf);
      stream.next_out = (unsigned char*)zOutBuf;
    }
    do{
      stream.avail_out = sizeof(zOutBuf);
      stream.next_out = (unsigned char*)zOutBuf;
      deflate(&stream, Z_FINISH);
      toOut = sizeof(zOutBuf) - stream.avail_out;
      if( toOut>skip ){
        blob_append(&body, &zOutBuf[skip], toOut - skip);
        skip = 0;
      }else{
        skip -= toOut;
      }
    }while( stream.avail_out==0 );
    nByte = stream.total_in;
    nByteCompr = stream.total_out - 2;
    deflateEnd(&stream);
  
    /* Go back and write the header, now that we know the compressed file size.
    */
    z = &blob_buffer(&body)[iStart];
    put32(&z[14], iCRC);
    put32(&z[18], nByteCompr);
    put32(&z[22], nByte);
  }
  
  /* Make an entry in the tables of contents
  */
  memset(zBuf, 0, sizeof(zBuf));
  put32(&zBuf[0], 0x02014b50);
  put16(&zBuf[4], 0x0317);
  put16(&zBuf[6], 0x000a);
  put16(&zBuf[8], 0);
  put16(&zBuf[10], iMethod);
  put16(&zBuf[12], dosTime);
  put16(&zBuf[14], dosDate);
  put32(&zBuf[16], iCRC);
  put32(&zBuf[20], nByteCompr);
  put32(&zBuf[24], nByte);
  put16(&zBuf[28], nameLen);
  put16(&zBuf[30], 9);
  put16(&zBuf[32], 0);
  put16(&zBuf[34], 0);
  put16(&zBuf[36], 0);
  put32(&zBuf[38], ((unsigned)iMode)<<16);
  put32(&zBuf[42], iStart);
  blob_append(&toc, zBuf, 46);
  blob_append(&toc, zName, nameLen);
  put16(&zExTime[2], 5);
  blob_append(&toc, zExTime, 9);
  nEntry++;
}


/*
** Write the ZIP archive into the given BLOB.
*/
void zip_close(Blob *pZip){
  int iTocStart;
  int iTocEnd;
  int i;
  char zBuf[30];

  iTocStart = blob_size(&body);
  blob_append(&body, blob_buffer(&toc), blob_size(&toc));
  iTocEnd = blob_size(&body);

  memset(zBuf, 0, sizeof(zBuf));
  put32(&zBuf[0], 0x06054b50);
  put16(&zBuf[4], 0);
  put16(&zBuf[6], 0);
  put16(&zBuf[8], nEntry);
  put16(&zBuf[10], nEntry);
  put32(&zBuf[12], iTocEnd - iTocStart);
  put32(&zBuf[16], iTocStart);
  put16(&zBuf[20], 0);
  blob_append(&body, zBuf, 22);
  blob_reset(&toc);
  *pZip = body;
  blob_zero(&body);
  nEntry = 0;
  for(i=0; i<nDir; i++){
    sqlite3_free(azDir[i]);
  }
  free(azDir);
  nDir = 0;
  azDir = 0;
}

/*
** COMMAND: test-filezip
**
** Generate a ZIP archive specified by the first argument that
** contains files given in the second and subsequent arguments.

  if( zDir && zDir[0] ){
    blob_appendf(&filename, "%s/", zDir);
  }
  nPrefix = blob_size(&filename);

  if( manifest_parse(&m, &mfile) ){
    char *zName;
    zip_set_timedate(m.rDate);
    blob_append(&filename, "manifest", -1);
    zName = blob_str(&filename);
    zip_add_folders(zName);
    zip_add_file(zName, &file);
    sha1sum_blob(&file, &hash);
    blob_reset(&file);
    blob_append(&hash, "\n", 1);
    blob_resize(&filename, nPrefix);
    blob_append(&filename, "manifest.uuid", -1);
    zName = blob_str(&filename);
    zip_add_file(zName, &hash);
    blob_reset(&hash);
    for(i=0; i<m.nFile; i++){
      int fid = uuid_to_rid(m.aFile[i].zUuid, 0);
      if( fid ){
        content_get(fid, &file);
        blob_resize(&filename, nPrefix);
        blob_append(&filename, m.aFile[i].zName, -1);
        zName = blob_str(&filename);
        zip_add_folders(zName);
        zip_add_file(zName, &file);
        blob_reset(&file);
      }
    }
    manifest_clear(&m);
  }else{
    blob_reset(&mfile);
    blob_reset(&file);