| 0,0 → 1,229 |
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| ; Splits command line to argv array. |
| ; Uses standard Windows rules: |
| ; * in normal mode, arguments are separated with spaces and tabs, |
| ; duplicate spaces and tabs are ignored |
| ; (two sequential spaces are the same as one); |
| ; * unescaped quote " in normal mode starts quoted mode, |
| ; it does not end the current argument, it is not included in the argument; |
| ; * spaces and tabs in quoted mode are included in the argument as is; |
| ; * unescaped quote " in quoted mode returns to normal mode, |
| ; it does not end the current argument, it is not included in the argument; |
| ; * quotes can be escaped with backslashes \ in both modes |
| ; (the recommended way), \" means copying " to the argument |
| ; without switching modes; |
| ; * backslashes not before a quote are just regular characters, |
| ; backslashes before a quote should be escaped by another backslash: |
| ; " means unescaped quote |
| ; \" means character " |
| ; \\" means character \ plus unescaped quote |
| ; \\\" means characters \" |
| ; and so on; |
| ; * quotes in quoted mode can also be escaped by doubling them, "" |
| ; (the confusing way); note that in normal mode "" means empty argument. |
| ; For example, the command line |
| ; begin"quoted mode"end\ \"escaped" "quotes" "1\" "" """escaped quotes 2""" |
| ; has 4 arguments: |
| ; 1) beginquoted modeend\ |
| ; 2) "escaped quotes 1" |
| ; 3) |
| ; 4) "escaped quotes 2" |
| ; The recommended way to create a command line with the same arguments: |
| ; "beginquoted modeend"\ "\"escaped quotes 1\"" "\"escaped quotes 2\"". |
| ; |
| ; in: esi -> command line |
| ; in: edi -> data for arguments, maybe null |
| ; in: edx -> pointers to arguments, maybe null |
| ; out: ebx = argument count |
| ; |
| ; There are too many branches and labels here, |
| ; isolate some of them into macro. |
| macro start_arg |
| ; Increments argument count; |
| ; if arguments are tracked, stores the current address. |
| { |
| local .label |
| test edx, edx |
| jz .label |
| mov [edx], edi |
| add edx, 4 |
| .label: |
| inc ebx |
| } |
| ; In typical cases decoded arguments and input line have large chunks in common. |
| ; When going through the input string, we do not copy arguments immediately, |
| ; but track size of last chunk that should be copied instead. |
| ; This macros copies the last chunk of data if arguments are tracked. |
| ; If arguments are tracked, ecx is reset to zero; |
| ; otherwise, we do not care about ecx. |
| macro copy_arg_data |
| { |
| local .label |
| test edi, edi |
| jz .label |
| dec esi |
| sub esi, ecx |
| rep movsb |
| inc esi |
| .label: |
| } |
| ; Process backslash. |
| macro process_slash |
| { |
| ; 1. Count number of backslashes. |
| local .label1, .label2 |
| xor ecx, ecx |
| .label1: |
| inc ecx |
| mov al, byte [esi] |
| inc esi |
| cmp al, '\' |
| jz .label1 |
| ; 2. If the next character is not ", backslash is a regular character; |
| ; copy all of them. |
| cmp al, '"' |
| jnz .label2 |
| ; 3. If the next character is ", then only half of backslashes |
| ; should be copied, other are escaping characters. |
| ; If number of backslashes is odd, include " to copied chunk |
| ; and advance to the next character. |
| shr ecx, 1 |
| jnc .label2 |
| mov al, byte [esi] |
| inc esi |
| inc ecx |
| .label2: |
| copy_arg_data |
| } |
| |
| ; Parser procedure. |
| proc parse_cmdline |
| ; Registers: |
| ; ebx = argc = argument count |
| ; ecx = size of last chunk if edi is nonzero, garbage otherwise |
| ; al = current input character = [esi-1] |
| ; esi = pointer to input past the current character |
| ; edi = zero or pointer to the next output data |
| ; edx = zero or pointer to the next output pointer |
| xor ebx, ebx |
| xor ecx, ecx |
| ; There are two large blocks of code for normal and quoted modes. |
| ; We start in normal mode. |
| ; 1. Processing in normal mode. |
| ; 1a. Skip initial spaces and tabs. |
| .skip_spaces: |
| mov al, byte [esi] |
| inc esi |
| cmp al, ' ' |
| jz .skip_spaces |
| cmp al, 9 |
| jz .skip_spaces |
| ; 1b. If the command line has ended, exit. |
| test al, al |
| jz .done |
| ; 1c. Any character in this state starts a new argument. |
| start_arg |
| ; 1d. Loop over the input string, watching for one of: |
| ; (space), (tab), (terminator), ", \ |
| ; All other characters should be copied as is. |
| ; The first character here cannot be (space), (tab) or (terminator), |
| ; but " and \ are possible. For these, skip 1e, because we have nothing |
| ; to copy yet, and go directly where 1f would direct us. |
| cmp al, '"' |
| jz .enter_quoted_mode |
| cmp al, '\' |
| jz .slash_normal |
| .normal_mode: |
| inc ecx |
| .enter_normal_mode: |
| mov al, byte [esi] |
| inc esi |
| .reenter_normal_mode: |
| cmp al, ' ' |
| jz .copydata |
| cmp al, 9 |
| jz .copydata |
| test al, al |
| jz .copydata |
| cmp al, '\' |
| jz .copydata |
| cmp al, '"' |
| jnz .normal_mode |
| .copydata: |
| ; 1e. Copy the found chunk. |
| copy_arg_data |
| ; 1f. One of (space), (tab), (terminator), ", \ is found. |
| ; For terminator, end the current argument and exit. |
| ; For \, go to 1h. |
| ; For ", switch to quoted mode. |
| test al, al |
| jz .done_termarg |
| cmp al, '\' |
| jz .slash_normal |
| cmp al, '"' |
| jz .enter_quoted_mode |
| ; 1g. If we are here, (space) or (tab) has occured in 1d. |
| ; End the current argument and restart processing from 1a. |
| test edi, edi |
| jz .skip_spaces |
| mov byte [edi], 0 |
| inc edi |
| jmp .skip_spaces |
| .done_termarg: |
| test edi, edi |
| jz .done |
| mov byte [edi], 0 |
| inc edi |
| .done: |
| ret |
| .slash_normal: |
| ; 1h. Process chunk of slashes with possible ending " if escaped |
| ; as described in process_slash macros. |
| ; After that, return to loop in 1d; note that the next character can be space. |
| process_slash |
| jmp .reenter_normal_mode |
| ; 2. Processing in quoted mode. |
| ; This block is simpler because the current argument never ends in quoted mode, |
| ; except when the input ends. |
| ; 2a. Loop over the input string, watching for one of: |
| ; (terminator), ", \. |
| .quoted_mode: |
| inc ecx |
| .enter_quoted_mode: |
| mov al, byte [esi] |
| inc esi |
| .reenter_quoted_mode: |
| test al, al |
| jz .copydata2 |
| cmp al, '\' |
| jz .copydata2 |
| cmp al, '"' |
| jnz .quoted_mode |
| .copydata2: |
| ; 2b. Copy the found chunk. |
| copy_arg_data |
| ; 2c. One of (terminator), ", \ is found. |
| ; For terminator, end the current argument and exit. |
| ; For \, go to 2d. |
| test al, al |
| jz .done_termarg |
| cmp al, '\' |
| jz .slash_quoted |
| ; For ", check whether the next character is also ": |
| ; for a single quote, switch to the normal mode 1d, |
| ; for a double quote, skip the first quote |
| ; and start a new chunk from the second one. |
| cmp byte [esi], '"' |
| jnz .enter_normal_mode |
| .double_quote: |
| inc esi |
| jmp .quoted_mode |
| .slash_quoted: |
| ; 2d. Process chunk of slashes with possible ending " if escaped |
| ; as described in process_slash macros. |
| ; After that, return to loop in 2a. |
| process_slash |
| jmp .reenter_quoted_mode |
| endp |
| purge start_arg |
| purge copy_arg_data |
| purge process_slash |
| Property changes: |
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| Added: svn:eol-style |
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| +native |
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| \ No newline at end of property |
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