ABAP_GZIP

CLASS zcl_abap_gzip DEFINITION PUBLIC. * RFC 1952 - GZIP file format specification version 4.3 * http://www.faqs.org/rfcs/rfc1952.html * Author: Otto Frost * Possible improvements * Check input * ID1, ID2, has correct values * CM is correct * Name, within ISO-8859-1 charset encoding * Comment, within ISO-8859-1 charset encoding * Set mtime to processingtime * Check that length of xlen < 256 * Handle CRC16 * Error handling * Tested with * gnu gzip/gunzip 1.3.5 under cygwin * winzip 8.1 SR1 can open the produced file * Test run on SAP XI 3.0 SP14, on windows platform. * Function modules gui_upload and gui_download may be used for * up and download of data * See example method for how to use the class PUBLIC SECTION. TYPES: t_flg(1) TYPE x. * flags CONSTANTS: ftext TYPE i VALUE 0. CONSTANTS: fhcrc TYPE i VALUE 1. CONSTANTS: fextra TYPE i VALUE 2. CONSTANTS: fname TYPE i VALUE 3. CONSTANTS: fcomment TYPE i VALUE 4. * 5, 6, 7 are reserved CONSTANTS: null(1) TYPE x VALUE '00'. TYPES: BEGIN OF t_file, id1(1) TYPE x, id2(1) TYPE x, cm(1) TYPE x, flg TYPE t_flg, mtime(4) TYPE x, xfl(1) TYPE x, os(1) TYPE x, xlen TYPE i, " 2 bytes xlenbytes TYPE xstring, name TYPE string, " zero terminated comment TYPE string, " zero terminated namex TYPE xstring, " zero terminated commentx TYPE xstring, " zero terminated crc16(2) TYPE x, compress TYPE xstring, crc32(4) TYPE x, isize TYPE i, " 4 bytes END OF t_file . DATA file TYPE t_file. METHODS constructor. METHODS: gzip IMPORTING raw_in TYPE xstring RETURNING value(gzip_out) TYPE xstring EXCEPTIONS zip_parse_error cx_parameter_invalid_range cx_sy_buffer_overflow. METHODS: gunzip IMPORTING gzip_in TYPE xstring RETURNING value(raw_out) TYPE xstring EXCEPTIONS zip_decompression_error cx_parameter_invalid_range cx_sy_buffer_overflow. METHODS: bit_swap IMPORTING x TYPE t_flg RETURNING value(y) TYPE t_flg. METHODS: get_flagbit IMPORTING x TYPE t_flg flag TYPE i RETURNING value(b) TYPE i. METHODS: set_flagbit IMPORTING x TYPE t_flg flag TYPE i RETURNING value(y) TYPE i. METHODS: get_file_attributes RETURNING value(file_attributes) TYPE t_file. METHODS set_name IMPORTING name TYPE string. METHODS set_comment IMPORTING comment TYPE string. METHODS set_xlenbytes IMPORTING xlenbytes TYPE xstring. METHODS set_mtime IMPORTING mtime TYPE xstring. METHODS set_compress_level IMPORTING compress_level TYPE i. METHODS example. PROTECTED SECTION. PRIVATE SECTION. DATA compress_level TYPE i. ENDCLASS. CLASS ZCL_ABAP_GZIP IMPLEMENTATION. * <SIGNATURE>---------------------------------------------------------------------------------------+ * | Instance Public Method ZCL_ABAP_GZIP->CONSTRUCTOR * +-------------------------------------------------------------------------------------------------+ * +--------------------------------------------------------------------------------------</SIGNATURE> METHOD constructor. compress_level = 6. ENDMETHOD. "constructor * <SIGNATURE>---------------------------------------------------------------------------------------+ * | Instance Public Method ZCL_ABAP_GZIP->GZIP * +-------------------------------------------------------------------------------------------------+ * | [--->] RAW_IN TYPE XSTRING * | [<-()] GZIP_OUT TYPE XSTRING * | [EXC!] ZIP_PARSE_ERROR * | [EXC!] CX_PARAMETER_INVALID_RANGE * | [EXC!] CX_SY_BUFFER_OVERFLOW * +--------------------------------------------------------------------------------------</SIGNATURE> METHOD gzip. DATA: x2(2) TYPE x, x4(4) TYPE x. DEFINE writex4. " write xstring x4 = &2. concatenate &1 x4 into &1 in byte mode. END-OF-DEFINITION. DEFINE write2. " write two bytes from integer x2 = &2. concatenate &1 x2+1(1) x2+0(1) into &1 in byte mode. END-OF-DEFINITION. DEFINE write4. " write four bytes from integer x4 = &2. concatenate &1 x4+3(1) x4+2(1) x4+1(1) x4+0(1) into &1 in byte mode. END-OF-DEFINITION. DATA oconv TYPE REF TO cl_abap_conv_out_ce. * TRY. CALL METHOD cl_abap_conv_out_ce=>create EXPORTING encoding = 'UTF-8' * ENDIAN = * REPLACEMENT = '#' * IGNORE_CERR = ABAP_FALSE RECEIVING conv = oconv. . * CATCH CX_PARAMETER_INVALID_RANGE . * CATCH CX_SY_CODEPAGE_CONVERTER_INIT . * ENDTRY. file-id1 = '1F'. file-id2 = '8B'. file-cm = '08'. file-os = 'FF'. " 255 Unknown ( ABAP ) file-isize = XSTRLEN( raw_in ). * TRY. CALL METHOD cl_abap_gzip=>compress_binary EXPORTING raw_in = raw_in raw_in_len = file-isize compress_level = compress_level IMPORTING gzip_out = file-compress * GZIP_OUT_LEN = . * CATCH CX_PARAMETER_INVALID_RANGE . * CATCH CX_SY_BUFFER_OVERFLOW . * ENDTRY. file-crc32 = cl_abap_zip=>crc32( raw_in ). CONCATENATE file-id1 file-id2 file-cm file-flg INTO gzip_out IN BYTE MODE. write4 gzip_out file-mtime. CONCATENATE gzip_out file-xfl file-os INTO gzip_out IN BYTE MODE. IF 1 = me->get_flagbit( x = file-flg flag = fextra ). file-xlen = XSTRLEN( file-xlenbytes ). write2 gzip_out file-xlen. CONCATENATE gzip_out file-xlenbytes INTO gzip_out IN BYTE MODE. ENDIF. IF 1 = me->get_flagbit( x = file-flg flag = fname ). * TRY. CALL METHOD oconv->convert EXPORTING data = file-name * N = -1 IMPORTING buffer = file-namex * LEN = . * CATCH CX_SY_CODEPAGE_CONVERTER_INIT . * CATCH CX_SY_CONVERSION_CODEPAGE . * CATCH CX_PARAMETER_INVALID_TYPE . * ENDTRY. CONCATENATE gzip_out file-namex null INTO gzip_out IN BYTE MODE. ENDIF. IF 1 = me->get_flagbit( x = file-flg flag = fcomment ). * TRY. CALL METHOD oconv->convert EXPORTING data = file-comment * N = -1 IMPORTING buffer = file-commentx * LEN = . * CATCH CX_SY_CODEPAGE_CONVERTER_INIT . * CATCH CX_SY_CONVERSION_CODEPAGE . * CATCH CX_PARAMETER_INVALID_TYPE . * ENDTRY. CONCATENATE gzip_out file-commentx null INTO gzip_out IN BYTE MODE. ENDIF. CONCATENATE gzip_out file-compress INTO gzip_out IN BYTE MODE. CLEAR file-compress. write4 gzip_out file-crc32. write4 gzip_out file-isize. ENDMETHOD. "gunzip * <SIGNATURE>---------------------------------------------------------------------------------------+ * | Instance Public Method ZCL_ABAP_GZIP->GUNZIP * +-------------------------------------------------------------------------------------------------+ * | [--->] GZIP_IN TYPE XSTRING * | [<-()] RAW_OUT TYPE XSTRING * | [EXC!] ZIP_DECOMPRESSION_ERROR * | [EXC!] CX_PARAMETER_INVALID_RANGE * | [EXC!] CX_SY_BUFFER_OVERFLOW * +--------------------------------------------------------------------------------------</SIGNATURE> METHOD gunzip. DATA: offset TYPE i. DEFINE next. " move offset offset = offset + &1. END-OF-DEFINITION. DATA: l1(1) TYPE x, h1(1) TYPE x, l2(1) TYPE x, h2(1) TYPE x, xstr TYPE xstring. DEFINE read2. " read two bytes as integer and move offset l1 = gzip_in+offset(1). offset = offset + 1. h1 = gzip_in+offset(1). offset = offset + 1. concatenate h1 l1 into xstr in byte mode. &1 = xstr. END-OF-DEFINITION. DEFINE read4. " read four bytes as integer and move offset l1 = gzip_in+offset(1). offset = offset + 1. h1 = gzip_in+offset(1). offset = offset + 1. l2 = gzip_in+offset(1). offset = offset + 1. h2 = gzip_in+offset(1). offset = offset + 1. concatenate h2 l2 h1 l1 into xstr in byte mode. &1 = xstr. END-OF-DEFINITION. * We convert all names from xstring into string DATA: conv TYPE REF TO cl_abap_conv_in_ce. conv = cl_abap_conv_in_ce=>create( ). DATA: msdos_date TYPE i, msdos_time TYPE i. * FIELD-SYMBOLS: <file> TYPE t_file, * <ext> TYPE t_ext. DATA b TYPE i. " BIT DATA: max_length TYPE i. DATA file TYPE t_file. DATA crc32 TYPE i. file-id1 = gzip_in+offset(1). next 1. file-id2 = gzip_in+offset(1). next 1. file-cm = gzip_in+offset(1). next 1. file-flg = gzip_in+offset(1). next 1. read4 file-mtime. file-xfl = gzip_in+offset(1). next 1. file-os = gzip_in+offset(1). next 1. * DO 8 TIMES. * GET BIT sy-index OF file-flg INTO b. * WRITE b NO-GAP. * ENDDO. b = me->get_flagbit( x = file-flg flag = fextra ). IF b = 1. read2 file-xlen. file-xlenbytes = gzip_in+offset(file-xlen). next file-xlen. ENDIF. b = me->get_flagbit( x = file-flg flag = fname ). IF b = 1. WHILE gzip_in+offset(1) <> '00'. CONCATENATE file-namex gzip_in+offset(1) INTO file-namex IN BYTE MODE. next 1. ENDWHILE. next 1. " skip 00 conv->convert( EXPORTING input = file-namex IMPORTING data = file-name ). ENDIF. b = me->get_flagbit( x = file-flg flag = fcomment ). IF b = 1. WHILE gzip_in+offset(1) <> '00'. CONCATENATE file-commentx gzip_in+offset(1) INTO file-commentx IN BYTE MODE. next 1. ENDWHILE. next 1. " skip 00 conv->convert( EXPORTING input = file-commentx IMPORTING data = file-comment ). ENDIF. b = me->get_flagbit( x = file-flg flag = fhcrc ). IF b = 1. read2 file-crc16. ENDIF. max_length = XSTRLEN( gzip_in ). max_length = max_length - offset. max_length = max_length - 8. " trailer length file-compress = gzip_in+offset(max_length). next max_length. read4 file-crc32. read4 file-isize. cl_abap_gzip=>decompress_binary( EXPORTING gzip_in = file-compress gzip_in_len = max_length IMPORTING raw_out = raw_out ). crc32 = cl_abap_zip=>crc32( raw_out ). IF crc32 <> file-crc32. RAISE zip_decompression_error. ENDIF. CLEAR file-compress. me->file = file. ENDMETHOD. "gunzip * <SIGNATURE>---------------------------------------------------------------------------------------+ * | Instance Public Method ZCL_ABAP_GZIP->BIT_SWAP * +-------------------------------------------------------------------------------------------------+ * | [--->] X TYPE T_FLG * | [<-()] Y TYPE T_FLG * +--------------------------------------------------------------------------------------</SIGNATURE> METHOD bit_swap. * in abap bytes are indexed * 1,2,3,4,5,6,7,8 * in gzip spec * 7,6,5,4,3,2,1,0 * why order is reversed * and 1 added to index in get_flagbit method DATA b TYPE i. " BIT DATA i TYPE i. i = 8. DO 8 TIMES. GET BIT sy-index OF x INTO b. SET BIT i OF y TO b. i = i - 1. ENDDO. ENDMETHOD. "bit_swap * <SIGNATURE>---------------------------------------------------------------------------------------+ * | Instance Public Method ZCL_ABAP_GZIP->GET_FLAGBIT * +-------------------------------------------------------------------------------------------------+ * | [--->] X TYPE T_FLG * | [--->] FLAG TYPE I * | [<-()] B TYPE I * +--------------------------------------------------------------------------------------</SIGNATURE> METHOD get_flagbit. DATA byte(1) TYPE x. DATA index TYPE i. byte = me->bit_swap( x = x ). index = 1 + flag. GET BIT index OF byte INTO b. ENDMETHOD. "get_flagbit * <SIGNATURE>---------------------------------------------------------------------------------------+ * | Instance Public Method ZCL_ABAP_GZIP->SET_FLAGBIT * +-------------------------------------------------------------------------------------------------+ * | [--->] X TYPE T_FLG * | [--->] FLAG TYPE I * | [<-()] Y TYPE I * +--------------------------------------------------------------------------------------</SIGNATURE> METHOD set_flagbit. DATA index TYPE i. DATA byte(1) TYPE x. index = flag + 1. byte = me->bit_swap( x = x ). SET BIT index OF byte. byte = me->bit_swap( x = byte ). y = byte. ENDMETHOD. "set_flagbit * <SIGNATURE>---------------------------------------------------------------------------------------+ * | Instance Public Method ZCL_ABAP_GZIP->GET_FILE_ATTRIBUTES * +-------------------------------------------------------------------------------------------------+ * | [<-()] FILE_ATTRIBUTES TYPE T_FILE * +--------------------------------------------------------------------------------------</SIGNATURE> METHOD get_file_attributes. file_attributes = me->file. ENDMETHOD. "get_file_attributes * <SIGNATURE>---------------------------------------------------------------------------------------+ * | Instance Public Method ZCL_ABAP_GZIP->SET_NAME * +-------------------------------------------------------------------------------------------------+ * | [--->] NAME TYPE STRING * +--------------------------------------------------------------------------------------</SIGNATURE> METHOD set_name. * methods set_name importing name type string. file-name = name. file-flg = me->set_flagbit( x = file-flg flag = fname ). ENDMETHOD. "set_name * <SIGNATURE>---------------------------------------------------------------------------------------+ * | Instance Public Method ZCL_ABAP_GZIP->SET_COMMENT * +-------------------------------------------------------------------------------------------------+ * | [--->] COMMENT TYPE STRING * +--------------------------------------------------------------------------------------</SIGNATURE> METHOD set_comment. * methods set_comment importing comment type string. file-comment = comment. file-flg = me->set_flagbit( x = file-flg flag = fcomment ). ENDMETHOD. "set_comment * <SIGNATURE>---------------------------------------------------------------------------------------+ * | Instance Public Method ZCL_ABAP_GZIP->SET_XLENBYTES * +-------------------------------------------------------------------------------------------------+ * | [--->] XLENBYTES TYPE XSTRING * +--------------------------------------------------------------------------------------</SIGNATURE> METHOD set_xlenbytes. * methods set_xlenbytes importing xlenbytes type xstring. file-xlenbytes = xlenbytes. file-flg = me->set_flagbit( x = file-flg flag = fextra ). ENDMETHOD. "set_xlenbytes * <SIGNATURE>---------------------------------------------------------------------------------------+ * | Instance Public Method ZCL_ABAP_GZIP->SET_MTIME * +-------------------------------------------------------------------------------------------------+ * | [--->] MTIME TYPE XSTRING * +--------------------------------------------------------------------------------------</SIGNATURE> METHOD set_mtime. file-mtime = mtime. ENDMETHOD. "set_mtime * <SIGNATURE>---------------------------------------------------------------------------------------+ * | Instance Public Method ZCL_ABAP_GZIP->SET_COMPRESS_LEVEL * +-------------------------------------------------------------------------------------------------+ * | [--->] COMPRESS_LEVEL TYPE I * +--------------------------------------------------------------------------------------</SIGNATURE> METHOD set_compress_level. me->compress_level = compress_level. IF compress_level = 9. file-xfl = '02'. ELSEIF compress_level = 1. file-xfl = '04'. ENDIF. ENDMETHOD. "set_compress_level * <SIGNATURE>---------------------------------------------------------------------------------------+ * | Static Public Method ZCL_ABAP_GZIP=>EXAMPLE * +-------------------------------------------------------------------------------------------------+ * +--------------------------------------------------------------------------------------</SIGNATURE> METHOD example. * You may use gui_upload and gui_download to * transfer the data, but that is not included * in this example DATA xstringin TYPE xstring. DATA xstringout TYPE xstring. DATA file TYPE zcl_abap_gzip=>t_file. DATA obj TYPE REF TO zcl_abap_gzip. CREATE OBJECT obj. * file without filename with content AAAAAA xstringin = '1F8B0800FBAF0D44020373740401007EDE1CAA06000000'. * a gzipped file with filename testa.txt, with content AAAAAA and a char with hex val x0A xstringin = '1F8B0808B4331044020374657374612E74787400737404012E007646C08507000000'. xstringout = obj->gunzip( gzip_in = xstringin ) . file = obj->get_file_attributes( ). xstringin = xstringout. CREATE OBJECT obj. obj->set_name( name = file-name ). obj->set_compress_level( 9 ). xstringout = obj->gzip( raw_in = xstringin ). ENDMETHOD. "example ENDCLASS.