COMMENT | Program to test string procedures STR_TEST.ASM Objective: To test all string processing procedures in STRING.ASM and to illustrate how indirect procedure call can be used. Inputs: As per queries. | Outputs: Displayed on the screen. CR EQU 0DH LF EQU 0AH STR_MAX EQU 128 .MODEL SMALL .STACK 100H .DATA proc_ptr_table DW str_len_fun,str_cpy_fun,str_cat_fun DW str_cmp_fun,str_chr_fun,str_cnv_fun DW str_mov_fun MAX_FUNCTIONS EQU ($ - proc_ptr_table)/2 choice_prompt DB 'You can test several functions.',CR,LF DB ' To test enter',CR,LF DB 'String length 1',CR,LF DB 'String copy 2',CR,LF DB 'String concatenate 3',CR,LF DB 'String compare 4',CR,LF DB 'Locate character 5',CR,LF DB 'Convert string 6',CR,LF DB 'Move string 7',CR,LF DB 'Invalid response terminates program.',CR,LF DB 'Please enter your choice: ',0 invalid_choice DB 'Invalid chioce - program terminates.',0 string0_msg DB 'Please enter a string: ',0 string1_msg DB 'Please enter the first string: ',0 string2_msg DB 'Please enter the second string: ',0 char_msg DB 'Please enter a search character: ',0 number_msg DB 'Please enter # places to move: ',0 string1 DB STR_MAX DUP (?) string2 DB STR_MAX DUP (?) str_len_msg DB 'String length = ',0 str_cpy_msg DB 'The copied string is: ',0 str_cat_msg DB 'First string now contains: ',0 str_match_msg DB 'Both strings match.',0 str1_below_msg DB 'First string is less than second string.',0 str1_above_msg DB 'First string is greater than second string.',0 str_chr_msg DB 'The character is located at: ',0 str_chr_err_msg DB 'No character match!',0 str_cnv_msg DB 'The converted string is: ',0 str_mov_msg DB 'The updated string is: ',0 no_string_msg DB 'Error: Not a string!',0 str_len_hdr_msg DB 'String length function selected.',0 str_cpy_hdr_msg DB 'String copy function selected.',0 str_cat_hdr_msg DB 'String concatenate function selected.',0 str_cmp_hdr_msg DB 'String compare function selected.',0 str_chr_hdr_msg DB 'Locate character function selected.',0 str_cnv_hdr_msg DB 'Convert string function selected.',0 str_mov_hdr_msg DB 'Move string function selected.',0 .CODE .486 INCLUDE io.mac EXTRN str_len:PROC, str_cpy:PROC EXTRN str_cat:PROC, str_cmp:PROC EXTRN str_chr:PROC, str_cnv:PROC EXTRN str_mov:PROC main PROC .STARTUP mov AX,DS mov ES,AX query_choice: xor BX,BX PutStr choice_prompt ; display menu GetCh BL ; read response nwln sub BL,'1' cmp BL,0 jb invalid_response cmp BL,MAX_FUNCTIONS jb response_ok invalid_response: PutStr invalid_choice jmp SHORT done response_ok: shl BL,1 ; multiply BL by 2 call proc_ptr_table[BX] ; indirect call jmp query_choice done: .EXIT main ENDP str_len_fun PROC PutStr str_len_hdr_msg nwln PutStr string0_msg GetStr string1,STR_MAX nwln push DS push OFFSET string1 call str_len call error1 PutStr str_len_msg PutInt AX nwln ret str_len_fun ENDP str_cpy_fun PROC PutStr str_cpy_hdr_msg nwln PutStr string0_msg GetStr string2,STR_MAX nwln push DS push OFFSET string2 push ES push OFFSET string1 call str_cpy call error1 PutStr str_cpy_msg PutStr string1 nwln ret str_cpy_fun ENDP str_cat_fun PROC PutStr str_cat_hdr_msg nwln PutStr string1_msg GetStr string1,STR_MAX nwln PutStr string2_msg GetStr string2,STR_MAX nwln push DS push OFFSET string2 push ES push OFFSET string1 call str_cat call error1 PutStr str_cat_msg PutStr string1 nwln ret str_cat_fun ENDP str_cmp_fun PROC PutStr str_cmp_hdr_msg nwln PutStr string1_msg GetStr string1,STR_MAX nwln PutStr string2_msg GetStr string2,STR_MAX nwln push DS push OFFSET string2 push ES push OFFSET string1 call str_cmp call error1 cmp AX,0 je str_match jg str1_above str1_below: PutStr str1_below_msg jmp SHORT sm_skip str_match: PutStr str_match_msg jmp SHORT sm_skip str1_above: PutStr Str1_above_msg sm_skip: nwln ret str_cmp_fun ENDP str_chr_fun PROC PutStr str_chr_hdr_msg nwln PutStr string0_msg GetStr string1,STR_MAX nwln PutStr char_msg GetCh AL nwln xor AH,AH push AX push DS push OFFSET string1 call str_chr call error1 cmp AX,0 jne skip_err PutStr str_chr_err_msg jmp SHORT finished skip_err: PutStr str_chr_msg sub AX,OFFSET string1-1 PutInt AX finished: nwln ret str_chr_fun ENDP str_cnv_fun PROC PutStr str_cnv_hdr_msg nwln PutStr string0_msg GetStr string2,STR_MAX nwln push DS push OFFSET string2 push ES push OFFSET string1 call str_cnv call error1 PutStr str_cnv_msg PutStr string1 nwln ret str_cnv_fun ENDP str_mov_fun PROC PutStr str_mov_hdr_msg nwln PutStr string0_msg GetStr string1,STR_MAX nwln PutStr number_msg GetInt DX nwln push DX push DS mov AX,OFFSET string1 cmp DX,0 jge skip1 sub AX,DX skip1: push AX call str_mov call error1 PutStr str_mov_msg PutStr string1 nwln ret str_mov_fun ENDP error1 PROC push AX jnc no_error PutStr no_string_msg nwln mov AX,4C01H ; return to DOS int 21H ; with error code 1 no_error: pop AX ret error1 ENDP END main