extern int ZEXPORT unzOpenCurrentFile3()

in zlib/contrib/minizip/unzip.c [1339:1507]

• 134 lines of code
• 26 McCabe index (conditional complexity)

extern int ZEXPORT unzOpenCurrentFile3(unzFile file, int* method,
                                       int* level, int raw, const char* password) {
    int err=UNZ_OK;
    uInt iSizeVar;
    unz64_s* s;
    file_in_zip64_read_info_s* pfile_in_zip_read_info;
    ZPOS64_T offset_local_extrafield;  /* offset of the local extra field */
    uInt  size_local_extrafield;    /* size of the local extra field */
#    ifndef NOUNCRYPT
    char source[12];
#    else
    if (password != NULL)
        return UNZ_PARAMERROR;
#    endif

    if (file==NULL)
        return UNZ_PARAMERROR;
    s=(unz64_s*)file;
    if (!s->current_file_ok)
        return UNZ_PARAMERROR;

    if (s->pfile_in_zip_read != NULL)
        unzCloseCurrentFile(file);

    if (unz64local_CheckCurrentFileCoherencyHeader(s,&iSizeVar, &offset_local_extrafield,&size_local_extrafield)!=UNZ_OK)
        return UNZ_BADZIPFILE;

    pfile_in_zip_read_info = (file_in_zip64_read_info_s*)ALLOC(sizeof(file_in_zip64_read_info_s));
    if (pfile_in_zip_read_info==NULL)
        return UNZ_INTERNALERROR;

    pfile_in_zip_read_info->read_buffer=(char*)ALLOC(UNZ_BUFSIZE);
    pfile_in_zip_read_info->offset_local_extrafield = offset_local_extrafield;
    pfile_in_zip_read_info->size_local_extrafield = size_local_extrafield;
    pfile_in_zip_read_info->pos_local_extrafield=0;
    pfile_in_zip_read_info->raw=raw;

    if (pfile_in_zip_read_info->read_buffer==NULL)
    {
        free(pfile_in_zip_read_info);
        return UNZ_INTERNALERROR;
    }

    pfile_in_zip_read_info->stream_initialised=0;

    if (method!=NULL)
        *method = (int)s->cur_file_info.compression_method;

    if (level!=NULL)
    {
        *level = 6;
        switch (s->cur_file_info.flag & 0x06)
        {
          case 6 : *level = 1; break;
          case 4 : *level = 2; break;
          case 2 : *level = 9; break;
        }
    }

    if ((s->cur_file_info.compression_method!=0) &&
/* #ifdef HAVE_BZIP2 */
        (s->cur_file_info.compression_method!=Z_BZIP2ED) &&
/* #endif */
        (s->cur_file_info.compression_method!=Z_DEFLATED))

        err=UNZ_BADZIPFILE;

    pfile_in_zip_read_info->crc32_wait=s->cur_file_info.crc;
    pfile_in_zip_read_info->crc32=0;
    pfile_in_zip_read_info->total_out_64=0;
    pfile_in_zip_read_info->compression_method = s->cur_file_info.compression_method;
    pfile_in_zip_read_info->filestream=s->filestream;
    pfile_in_zip_read_info->z_filefunc=s->z_filefunc;
    pfile_in_zip_read_info->byte_before_the_zipfile=s->byte_before_the_zipfile;

    pfile_in_zip_read_info->stream.total_out = 0;

    if ((s->cur_file_info.compression_method==Z_BZIP2ED) && (!raw))
    {
#ifdef HAVE_BZIP2
      pfile_in_zip_read_info->bstream.bzalloc = (void *(*) (void *, int, int))0;
      pfile_in_zip_read_info->bstream.bzfree = (free_func)0;
      pfile_in_zip_read_info->bstream.opaque = (voidpf)0;
      pfile_in_zip_read_info->bstream.state = (voidpf)0;

      pfile_in_zip_read_info->stream.zalloc = (alloc_func)0;
      pfile_in_zip_read_info->stream.zfree = (free_func)0;
      pfile_in_zip_read_info->stream.opaque = (voidpf)0;
      pfile_in_zip_read_info->stream.next_in = (voidpf)0;
      pfile_in_zip_read_info->stream.avail_in = 0;

      err=BZ2_bzDecompressInit(&pfile_in_zip_read_info->bstream, 0, 0);
      if (err == Z_OK)
        pfile_in_zip_read_info->stream_initialised=Z_BZIP2ED;
      else
      {
        free(pfile_in_zip_read_info->read_buffer);
        free(pfile_in_zip_read_info);
        return err;
      }
#else
      pfile_in_zip_read_info->raw=1;
#endif
    }
    else if ((s->cur_file_info.compression_method==Z_DEFLATED) && (!raw))
    {
      pfile_in_zip_read_info->stream.zalloc = (alloc_func)0;
      pfile_in_zip_read_info->stream.zfree = (free_func)0;
      pfile_in_zip_read_info->stream.opaque = (voidpf)0;
      pfile_in_zip_read_info->stream.next_in = 0;
      pfile_in_zip_read_info->stream.avail_in = 0;

      err=inflateInit2(&pfile_in_zip_read_info->stream, -MAX_WBITS);
      if (err == Z_OK)
        pfile_in_zip_read_info->stream_initialised=Z_DEFLATED;
      else
      {
        free(pfile_in_zip_read_info->read_buffer);
        free(pfile_in_zip_read_info);
        return err;
      }
        /* windowBits is passed < 0 to tell that there is no zlib header.
         * Note that in this case inflate *requires* an extra "dummy" byte
         * after the compressed stream in order to complete decompression and
         * return Z_STREAM_END.
         * In unzip, i don't wait absolutely Z_STREAM_END because I known the
         * size of both compressed and uncompressed data
         */
    }
    pfile_in_zip_read_info->rest_read_compressed =
            s->cur_file_info.compressed_size ;
    pfile_in_zip_read_info->rest_read_uncompressed =
            s->cur_file_info.uncompressed_size ;


    pfile_in_zip_read_info->pos_in_zipfile =
            s->cur_file_info_internal.offset_curfile + SIZEZIPLOCALHEADER +
              iSizeVar;

    pfile_in_zip_read_info->stream.avail_in = (uInt)0;

    s->pfile_in_zip_read = pfile_in_zip_read_info;
                s->encrypted = 0;

#    ifndef NOUNCRYPT
    if (password != NULL)
    {
        int i;
        s->pcrc_32_tab = get_crc_table();
        init_keys(password,s->keys,s->pcrc_32_tab);
        if (ZSEEK64(s->z_filefunc, s->filestream,
                  s->pfile_in_zip_read->pos_in_zipfile +
                     s->pfile_in_zip_read->byte_before_the_zipfile,
                  SEEK_SET)!=0)
            return UNZ_INTERNALERROR;
        if(ZREAD64(s->z_filefunc, s->filestream,source, 12)<12)
            return UNZ_INTERNALERROR;

        for (i = 0; i<12; i++)
            zdecode(s->keys,s->pcrc_32_tab,source[i]);

        s->pfile_in_zip_read->pos_in_zipfile+=12;
        s->encrypted=1;
    }
#    endif


    return UNZ_OK;
}