-; prompt for user
-; no args - reads from globals
-repl:
-
- %define CMDSTR 4 ; the previous line read from user
-
- push ebp
- mov ebp, esp
-
- sub esp, 4
-
- _repl_loop:
-
- ; print the prompt
- push prompt_str
- call printf
- push DWORD [stdout]
- call fflush
-
- ; read line from stdin
- push 0
- call readLine
-
- mov DWORD [ebp-CMDSTR], eax
-
- ; commands are single char for now
- cmp ecx, 1
- jne _repl_invalid_cmd
-
- ; parse commands
- mov eax, DWORD [ebp-CMDSTR]
- mov eax, [eax]
-
- ; q exists program =-=-=-=-=-=-=-=-=-=-=-=-=
- mov eax, DWORD [ebp-CMDSTR]
- cmp BYTE [eax], 'q'
- jne _repl_cmd_quit_end
- jmp _repl_exit
- _repl_cmd_quit_end:
-
- ; p prints current line =-=-=-=-=-=-=-=-=-=-=
- mov eax, DWORD [ebp-CMDSTR]
- cmp BYTE [eax], 'p'
- jne _repl_cmd_print_end
-
- mov eax, DWORD [cur_line]
- mov ecx, 4
- mul ecx
- add eax, [buffer]
- push DWORD [eax]
- push echo_str
- call printf
- jmp _repl_continue
- _repl_cmd_print_end:
-
- ; n prints the current line number =-=-=-=-=-=-=-=
- mov eax, DWORD [ebp-CMDSTR]
- cmp BYTE [eax], 'n'
- jne _repl_cmd_number_end
-
- push DWORD [cur_line]
- push currentline_str
- call printf
-
- jmp _repl_continue
- _repl_cmd_number_end:
-
- ; - goes to prev line =-=-=-=-=-=-=-=-=-=-=-=-=
- mov eax, DWORD [ebp-CMDSTR]
- cmp BYTE [eax], '-'
- jne _repl_cmd_decline_end
-
- ; make sure we are within bounds
- mov eax, DWORD [cur_line]
- sub eax, 1
- cmp eax, 0
- jl _repl_invalid_addr
-
- sub DWORD [cur_line], 1
-
- jmp _repl_continue
- _repl_cmd_decline_end:
-
- ; + goes to next line =-=-=-=-=-=-=-=-=-=-=-=-=
- mov eax, DWORD [ebp-CMDSTR]
- cmp BYTE [eax], '+'
- jne _repl_cmd_incline_end
-
- ; make sure we are within bounds
- mov eax, DWORD [cur_line]
- add eax, 1
- cmp eax, [buffer_lines]
- jge _repl_invalid_addr
-
- add DWORD [cur_line], 1
-
- jmp _repl_continue
- _repl_cmd_incline_end:
-
- ; g goes to first line =-=-=-=-=-=-=-=-=-=-=-=-=
- mov eax, DWORD [ebp-CMDSTR]
- cmp BYTE [eax], 'g'
- jne _repl_cmd_jumptop_end
-
- mov DWORD [cur_line], 0x00
-
- jmp _repl_continue
- _repl_cmd_jumptop_end:
-
- ; G goes to last line =-=-=-=-=-=-=-=-=-=-=-=-=
- mov eax, DWORD [ebp-CMDSTR]
- cmp BYTE [eax], 'G'
- jne _repl_cmd_jumpbot_end
-
- mov eax, DWORD [buffer_lines]
- sub eax, 1
- mov DWORD [cur_line], eax
-
- jmp _repl_continue
- _repl_cmd_jumpbot_end:
-
- ; c changes the current line =-=-=-=-=-=-=-=-=-=
- mov eax, DWORD [ebp-CMDSTR]
- cmp BYTE [eax], 'c'
- jne _repl_cmd_change_end
-
- ; read a new line to use
- push 0
- call readLine
-
- mov esi, eax
-
- ; free old string
- mov eax, [cur_line]
- mov ecx, 4
- mul ecx
- add eax, [buffer]
- push DWORD [eax]
- call free
-
- ; insert new string
- mov eax, [cur_line]
- mov ecx, 4
- mul ecx
- add eax, DWORD [buffer]
- mov [eax], esi
-
- jmp _repl_continue
- _repl_cmd_change_end:
-
-
- jmp _repl_invalid_cmd
-
- ; some error messages
- _repl_invalid_cmd:
- push invalidcmd_str
- call printf
- jmp _repl_continue
-
- _repl_invalid_addr:
- push invalidaddr_str
- call printf
- jmp _repl_continue
-
- _repl_continue:
- jmp _repl_loop
-
- _repl_exit:
-
- %undef CMDSTR
-
- mov esp, ebp
- pop ebp
- ret
-