; **************************************************************************** ; SH.ASM (sh8086.asm) - Retro Unix 8086 v1 Shell - /bin/sh ; ---------------------------------------------------------------------------- ; ; RETRO UNIX 8086 (Retro Unix == Turkish Rational Unix) ; Operating System Project (v0.1) by ERDOGAN TAN (Beginning: 11/07/2012) ; Retro UNIX 8086 v1 - /bin/sh file ; ; [ Last Modification: 23/06/2022 ] ; ; Derivation from UNIX Operating System (v1.0 for PDP-11) ; (Original) Source Code by Ken Thompson (Bell Laboratories, 1971-1972) ; ; **************************************************************************** ; ; ; ; ; ; SHELL03.ASM, 27/06/2014 ; ; **************************************************************************** ; SHELL05.ASM (modified SHELL04.ASM) - 19/06/2022 - ; Assembler: MASM 6.14 ; masm sh8086.asm sh8086.obj sh8086.lst ; link /t sh8086.obj ; ; (sh8086.bin) ; SHELL05.ASM - 19/06/2022 (sh.asm, Retro UNIX 8086 v1, MASM 6.14) ; sh6.s (17/06/2022, Retro UNIX 386 v1) -- (modified sh2.s) -- ; sh5.s (17/06/2022, Retro UNIX 386 v1.1) -- (modified sh2.s) -- ; sh4.s (13/06/2022, Retro UNIX 386 v1.2) -- (modified sh2.s) --- ; SHELL04.ASM - 29/05/2022 (sh.asm, Retro UNIX 8086 v1, MASM 6.14) ; sh3.s (29/05/2022, Retro UNIX 386 v1) -- (modified sh0.s) --- ; sh2.s (29/05/2022, Retro UNIX 386 v1.1 & v1.2) -- (modified sh1.s) -- ; sh1.s (03/01/2016, Retro UNIX 386 v1.1) ; sh0.s (28/12/2015, Retro UNIX 386 v1, NASM 2.11, 32 bit version of 'sh.asm') ; SHELL03.ASM, 13/11/2013 - 27/06/2014 (sh.asm, Retro UNIX 8086 v1, MASM 6.11) .8086 ; 12/01/2022 (Retro UNIX 386 v1.2) ; 13/10/2015 ; 27/08/2015 ; 24/08/2015 ; 08/04/2014 ; 13/11/2013 ; UNIX v1 system calls _rele equ 0 _exit equ 1 _fork equ 2 _read equ 3 _write equ 4 _open equ 5 _close equ 6 _wait equ 7 _creat equ 8 _link equ 9 _unlink equ 10 _exec equ 11 _chdir equ 12 _time equ 13 _mkdir equ 14 _chmod equ 15 _chown equ 16 _break equ 17 _stat equ 18 _seek equ 19 _tell equ 20 _mount equ 21 _umount equ 22 _setuid equ 23 _getuid equ 24 _stime equ 25 _quit equ 26 _intr equ 27 _fstat equ 28 _emt equ 29 _mdate equ 30 _stty equ 31 _gtty equ 32 _ilgins equ 33 _sleep equ 34 ; Retro UNIX 8086 v1 feature only ! _msg equ 35 ; Retro UNIX 386 v1 feature only ! _geterr equ 36 ; Retro UNIX 386 v1 feature only ! ; 12/01/2022 - Retro UNIX 386 v1.2 ; Retro UNIX 386 v2 system calls _setgid equ 37 _getgid equ 38 _sysver equ 39 ; (get) Retro Unix 386 version ;;; sys macro syscallnumber, arg1, arg2, arg3 ; Retro UNIX 8086 v1 system call. ifnb mov bx, arg1 endif ifnb mov cx, arg2 endif ifnb mov dx, arg3 endif mov ax, syscallnumber int 20h endm ; 19/06/2022 ;sysstat structure stat_inode equ 0 stat_mode equ 2 stat_nlinks equ 4 stat_uid equ 5 stat_size equ 6 stat_dskptr equ 8 stat_ctime equ 24 stat_mtime equ 28 stat_rsvd equ 32 parbuf equ bssstart ; 1000 bytes param equ bssstart+1000 ; 2 bytes glflag equ bssstart+1002 ; 2 bytes infile equ bssstart+1004 ; 2 bytes outfile equ bssstart+1006 ; 2 bytes parp_2 equ bssstart+1008 ; 2 bytes parp equ bssstart+1010 ; 200 bytes inbuf equ bssstart+1210 ; 256 bytes inbufp equ bssstart+1466 ; 2 bytes einbuf equ bssstart+1468 ; 2 bytes och equ bssstart+1470 ; 2 bytes shellarg equ bssstart+1472 ; 2 bytes escap equ bssstart+1474 ; 2 bytes stbuf equ bssstart+1476 ; 34 bytes bssend equ bssstart+1510 ; Retro UNIX 8086 v1 system call format: ; sys systemcall (ax) , , ;----------------------------------------------------------------- ; CODE ;----------------------------------------------------------------- UNIX SEGMENT PUBLIC 'CODE' assume cs:UNIX,ds:UNIX,es:UNIX,ss:UNIX START_CODE: ;/ sh -- command interpreter ; 19/06/2022 ;;clear BSS ;mov cx, ((bss_end - bss_start) + 1) / 2 ;sub ax, ax ;mov di, bss_start ;rep stosw s0: ; 19/06/2022 - Retro UNIX 8086 v1 (2022 modification) ;mov byte ptr [_echo], 1 ; 06/12/2013 mov bp, sp ; mov sp,r5 mov word ptr [shellarg], bp ; mov r5,shellarg / save orig sp in shellarg mov bx, word ptr [BP]+2 cmp byte ptr [BX], '-' ; cmpb *2(r5),$'- / was this sh called by init or login jne short s1 ; bne 2f / no sys _intr, 0 ; sys intr; 0 / yes, turn off interrupts sys _quit, 0 ; sys quit; 0 sys _write, 1, msg_unix_sh, msgsh_size s1: ;2: sys _getuid ; sys getuid / who is user ;and ax, ax and al, al ; tst r0 / is it superuser jnz short s2 ; bne 2f / no mov byte ptr [at], '#' ; movb $'#,at / yes, set new prompt symbol s2: ;2: cmp word ptr [BP], 1 ; cmp (r5),$1 / tty input? jna short newline ; ble newline / yes, call with '-' (or with no command ; / file name) xor bx, bx ; clr r0 / no, set tty sys _close ; sys close / close it mov bx, word ptr [BP]+4 ; arg 1 ; mov 4(r5),0f / get new file name xor cx, cx ; arg 2 sys _open ; sys open; 0:..; 0 / open it jnc short s3 ; bec 1f / branch if no error mov si, offset msgNotFound call error ; jsr r5,error / error in file name ; ; .even sys _exit ; sys exit s3: ;1: mov byte ptr [at], 0 ; clr at / clear prompt character, if reading non-tty ; / input file jmp short newcom newline: cmp byte ptr [at], 0 ; tst at / is there a prompt symbol jna short newcom ; beq newcom / no ; mov $1,r0 / yes nl: sys _write, 1, prompt, p_size ;sys _write, 1, at, 2 ; sys write; at; 2. / print prompt newcom: mov sp, word ptr [shellarg] ; mov shellarg,sp / ;mov si, offset parbuf mov si, parbuf ; 19/06/2022 ; mov $parbuf,r3 / initialize command list area ;mov di, offset parp mov di, parp ; 19/06/2022 ; mov $parp,r4 / initialize command list pointers xor ax, ax mov word ptr [infile], ax ; 0 ; clr infile / initialize alternate input mov word ptr [outfile], ax ; 0 ; clr outfile / initialize alternate output mov byte ptr [glflag], al ; 0 ;mov word ptr [glflag], ax ; 0 ; clr glflag / initialize global flag ; 19/06/2022 mov byte ptr [FCAT], al ; 0 newarg: call blank ; jsr pc,blank / squeeze out leading blanks call delim je short nch4 ; '\n', ';', '&' ; jsr r5,delim / is new character a ; \n or & ; br 2f / yes push si ; mov r3,-(sp) / no, push arg pointer onto stack mov bp, sp cmp al, '<' ; cmp r0,$'< / new input file? jne short na1 ; bne 1f / no mov word ptr [infile], si ; mov (sp),infile / yes, save arg pointer ; 19/06/2022 ;jmp short na4 jmp short na3 ;mov word ptr [BP], 0 ; clr (sp) / clear pointer ;jmp short nch1 ; br 3f na1: ;1: cmp al, '>' ; cmp r0,$'> / new output file? jne short nch0 ;jne short newchar ; bne newchar / no mov word ptr [outfile], si ; mov (sp),outfile / yes, save arg pointer ; 19/06/2022 call getc cmp al, '>' jne short na2 ; mov byte ptr [FCAT], al ; '>>' jmp short na3 na2: cmp al, 20h ; ' ' jne short na4 na3: call blank na4: mov word ptr [BP], 0 ; clr (sp) / clear pointer ;jmp short nch1 ; br 3f ; 23/06/2022 jmp short nch10 newchar: cmp al, 20h ; cmp $' ,r0 / is character a blank je short nch2 ; beq 1f / branch if it is (blank as arg separator) cmp al, 8Dh ; 128 + 13 je short nch2 ; cmp $'\n+200,r0 / treat \n preceded by \ ; beq 1f / as blank nch0: call putc ; jsr pc,putc / put this character in parbuf list nch1: ;3: call getc ; jsr pc,getc / get next character nch10: call delim jne short newchar ;jz short nch2 ; '\n', ';', '&' ; jsr r5,delim / is char a ; \n or &, ; br 1f / yes ;jmp short newchar ; br newchar / no, start new character tests nch2: ;1: mov byte ptr [SI], 0 inc si ; clrb (r3)+ / end name with \0 when read blank, ; or delim pop bx mov word ptr [DI], bx ; mov (sp)+,(r4)+ / move arg ptr to parp location or bx, bx jz short nch3 ;jnz short nch3 ; bne 1f / if (sp)=0, in file or out file points ; to arg inc di inc di ; tst -(r4) / so ignore dummy (0), in pointer list nch3: ;1: call delim jne short newarg ;jz short nch4 ; '\n', ';', '&' ; jsr r5,delim / is char a ; \n or &. ; br 2f / yes ;jmp short newarg ; br newarg / no, start newarg processing nch4: ;2: mov word ptr [DI], 0 ; clr (r4) / \n, &, or ; takes to here ; / (end of arg list) after 'delim' call push ax ; mov r0,-(sp) / save delimiter in stack call docom ; jsr pc,docom / go to exec command in parbuf mov bp, sp cmp byte ptr [BP], '&' ; cmpb (sp),$'& / get a new command without wait? ;je short newcom ; beq newcom / yes ; 19/06/2022 jne short nch9 jmp newcom nch9: and dx, dx ; tst r1 / was chdir just executed or line ended ; / with ampersand? jz short nch6 ; beq 2f / yes nch5: ;1: sys _wait ; sys wait / no, wait for new process to terminate ; / command executed) jc short nch6 ; bcs 2f / no, children not previously waited for cmp ax, dx ; cmp r0,r1 / is this my child jne short nch5 ; bne 1b nch6: ;2: cmp byte ptr [BP], 0 ; 27/06/2014 (EOT, COM1/COM2) ;je newline ; 29/05/2022 jne short nch8 nch7: jmp newline nch8: cmp byte ptr [BP], 0Dh ;cmp byte ptr [BP], 0Ah ; cmp (sp),$'\n / was delimiter a new line ;je newline ; ; beq newline / yes ;jmp newcom ; ; br newcom / no, pick up next command ; 29/05/2022 je short nch7 jmp newcom docom: ;sub di, offset parp sub di, parp ; 19/06/2022 ; sub $parp,r4 / out arg count in r4 jnz short dcom1 ; bne 1f / any arguments? dcom0: sub dx, dx ; 0 ; clr r1 / no, line ended with ampersand retn ; rts pc / return from call dcom1: ;1: mov bx, di ; 06/12/2013 mov si, offset qecho call chcom jnz short dcom7 cmp bl, 4 jne short dcom8 mov bx, word ptr [parp+2] cmp byte ptr [BX], 'o' jne short dcom9 inc bx sub al, al ; 23/06/2022 cmp byte ptr [BX], 'n' jne short dcom10 inc bx ;cmp byte ptr [BX], 0 ; 23/06/2022 cmp byte ptr [BX], al ; 0 ? ja short dcom9 ;mov byte ptr [_echo], 1 inc al ; al = 1 dcom13: mov byte ptr [_echo], al jmp short dcom0 dcom10: ; 06/12/2013 cmp word ptr [BX], 'ff' jne short dcom9 inc bx inc bx ;cmp byte ptr [BX], 0 ;ja short dcom9 ;mov byte ptr [_echo], 0 ;jmp short dcom0 ; 23/06/2022 ; al = 0 cmp byte ptr [BX], al ; 0 ? jna short dcom13 dcom9: ; 06/12/2013 mov si, offset msgNoCmd call error jmp short dcom0 dcom7: mov si, offset qchdir call chcom jnz short dcom4 ; jsr r5,chcom; qchdir / is command chdir? ; br 2f / command not chdir dcom12: cmp bl, 4 ;cmp bx, 4 ; cmp r4,$4 / prepare to exec chdir, ; 4=arg count x 2 je short dcom2 ; beq 3f dcom8: mov si, offset msgArgCount call error ; jsr r5,error / go to print error ; ; .even ;jmp short dcom3 ; br 4f jmp short dcom0 dcom2: ;3: ;mov parp+2,0f / more directory name to sys call mov bx, word ptr [parp+2] sys _chdir ; sys chdir; 0:0 / exec chdir jnc short dcom3 ; bec 4f / no error exit mov si, msgBadDir call error ; jsr r5,error / go to print error ; ; .even ; / this diagnostic dcom3: ;4: xor dx, dx ; 0 ; clr r1 / set r1 to zero to skip wait retn ; rts pc / and return dcom4: ;2: ; 06/12/2013 mov si, offset qcd call chcom jz short dcom12 dcom11: mov si, offset glogin call chcom jnz short dcom5 ; jsr r5,chcom; glogin / is command login? ; br 2f / not loqin, go to fork sys _exec, parbuf, parp ; sys exec; parbuf; parp / exec login sys _exec, binpb, parp ; sys exec; binpb; parp / or /bin/login dcom5: ;2: / no error return?? mov bx, offset newproc ; child process will return to 'newproc' address sys _fork ; sys fork / generate sh child process ; for command ; br newproc / exec command with ; new process ; parent process will return here jnc short dcom6 ; bec 1f / no error exit, old process mov si, offset msgTryAgain call error ; jsr r5,error / go to print error ; ; .even / this diagnostic jmp newline ; jmp newline / and return for next try dcom6: ;1: mov dx, ax ; child process ID ; mov r0,r1 / save id of child sh retn ; rts pc / return to "jsr pc, docom" call ; in parent sh error: sys _write, 1, nextline, 2 s4: lodsb mov byte ptr [och], al ; movb (r5)+,och / pick up diagnostic character and al, al jz short s5 ; beq 1f / 0 is end of line sys _write, 1, och, 1 ; mov $1,r0 / set for tty output ; sys write; och; 1 / print it jmp short s4 ;jmp short error ; br error / continue to get characters s5: ;1: ;inc si ; inc r5 / inc r5 to point to return ;and si, 0FFFEh ;shr si, 1 ;shl si, 1 ; bic $1,r5 / make it even sys _seek, 0, 0, 2 ; clr r0 / set for input ; sys seek; 0; 2 / exit from runcom. skip to ; / end of input file retn ;; rts r5 ; unix v2 shell ; 29/05/2022 ;; (not in original unix v1 'sh.s') chcom: ; / has no effect if tty input ; mov (r5)+,r1 / glogin gchdir r1, bump r5 ;mov di, offset parbuf mov di, parbuf ; 19/06/2022 ; mov $parbuf,r2 / command address r2 'login' s6: ;1: lodsb ; movb (r1)+,r0 / is this command 'chdir' scasb ; cmpb (r2)+,r0 / compare command name byte ; / with 'login' or 'chdir' jne short s7 ; bne 1f / doesn't compare or al, al ; tst r0 / is this jnz short s6 ; bne 1b / end of names ; tst (r5)+ / yes, bump r5 again to execute ; / login or chdir s7: ;1: retn ; rts r5 / no, return to exec command putc: cmp al, 27h ; ' ; cmp r0,$'' / single quote? je short pch1 ; beq 1f / yes cmp al, 22h ; " ; cmp r0,$'" / double quote je short pch1 ; beq 1f / yes and al, 7Fh ; bic $!177,r0 / no, remove 200, if present mov byte ptr [SI], al inc si ; movb r0,(r3)+ / store character in parbuf retn ; rts pc pch1: ;1: push ax ; mov r0,-(sp) / push quote mark onto stack pch2: ;1: call getc ; jsr pc,getc / get a quoted character test al, al ; 27/06/2014 (0 = EOT, COM1/COM2) jz short s8 cmp al, 0Dh ;cmp al, 0Ah ; \n ; cmp r0,$'\n / is it end or line jne short pch3 ; bne 2f / no s8: mov si, offset msgImbalance call error ; jsr r5,error / yes, indicate missing ; quote mark ; <"' imbalance\n\0>; .even jmp newline ; jmp newline / ask for new line pch3: ;2: mov bp, sp cmp byte ptr [BP], al ; cmp r0,(sp) / is this closing quote mark je short pch4 ; beq 1f / yes and al, 7Fh ; bic $!177,r0 / no, strip off 200 ; if present mov byte ptr [SI], al inc si ; movb r0,(r3)+ / store quoted character ; in parbuf jmp short pch2 ; br 1b / continue pch4: ;1: pop ax ; tst (sp)+ / pop quote mark off stack retn ; rts pc / return ; / thp`e new process newproc: mov si, word ptr [infile] or si, si jz short np2 ; mov infile,0f / move pointer to new file name ; beq 1f / branch if no alternate read file given cmp byte ptr [SI], 0 ; tstb *0f jna short np1 ; beq 3f / branch if no file name given ; 19/06/2022 - Retro UNIX 8086 v1 (2022 modification) sys _stat, si, stbuf ; get file (inode) status jc short np1 ; ; (regular files, disk blocks may be used as input source) ; ((pseudo tty input redirection not allowed)) mov ax, word ptr [stbuf] ; inode number cmp ax, 19 ; > tty9 inode number (regular file) ? ja short np13 ; yes cmp al, 10 ; < tty0 ? jnb short np1 ; yes cmp al, 1 je short np1 np13: sys _close, 0 ; clr r0 / set tty input file name ; sys close / close it sys _open, si, 0 ; sys open; 0:..; 0 / open new input file ; for reading jnc short np2 ; bcc 1f / branch if input file ok np1: ;3: mov si, offset msgInputFile call error ; jsr r5,error / file not ok, print error ; ; .even / this diagnostic sys _exit ; sys exit / terminate this process ; and make parent sh np2: ;1: mov si, word ptr [outfile] ; mov outfile,r2 / more pointer to new file name and si, si jz short np6 ; beq 1f / branch if no alternate write file ; 19/06/2022 np11: cmp byte ptr [SI], 0 jna short np4 ;cmp byte ptr [SI], '>' ; cmpb (r2),$'> / is > at beqinning of file name? ;jne short np3 ; bne 4f / branch if it isn't ;inc si ; inc r2 / yes, increment pointer ; 23/06/2022 sys _stat, si, stbuf ; get file (inode) status jc short np3 ; 19/06/2022 ; Block devices and dirs must not be target test byte ptr [stbuf+stat_mode+1], 40h ; directory ? jnz short np4 ; yes ; error mov ax, word ptr [stbuf] ; inode number cmp ax, 41 ; regular file ? ja short np14 ; yes cmp al, 8 ; > hd3 inode number ? ja short np12 ; yes ; character device cmp al, 3 ; >= fd0 inode number ? jnb short np4 ; yes ; output file error np12: sys _open, si, 1 ; mov r2,0f ; sys open; 0:..; 1 / open file for writing jnc short np5 ; bec 3f / if no error ; 19/06/2022 np4: ;2: mov si, offset msgOutputFile call error ; jsr r5,error ; ; .even sys _exit ; sys exit ;jmp short np4 ; 19/06/2022 np14: cmp byte ptr [FCAT], '>' ; '>>' ? je short np12 ; no, '>' np3: ;4: sys _creat, si, 15 ; Decimal 15 = Octal 17 ; mov r2,0f ; sys creat; 0:..; 17 / create new file ; with this name ;jnc short np5 ; bec 3f / branch if no error ; 19/06/2022 jc short np4 np5: ;3: sys _close, ax ; sys close / close the new write file ; mov r2,0f / move new name to open np10: sys _close, 1 ; mov $1,r0 / set tty file name ; sys close / close it sys _open, si, 1 ; sys open; 0:..; 1 / open new output file, ; /it now has file descriptor 1 ; 19/06/2022 cmp byte ptr [FCAT], '>' ; '>>' jne short np6 sys _seek, ax, 0, 2 ; sys seek; 0; 2 / set pointer to ; current end of file np6: ;1: cmp byte ptr [glflag], 0 ; tst glflag / was *, ? or [ encountered? ja short np9 ; bne 1f / yes sys _exec, parbuf, parp ; sys exec; parbuf; parp / no, execute ; this command sys _exec, binpb, parp ; sys exec; binpb; parp / or /bin/this command ;------ 29/05/2022 - unix v2 shell ; (source code from disassembled /bin/sh binary) ; following part is not existing in v2 shell ; ;np7: ;2: ; sys _stat, binpb, inbuf ; ; sys stat; binpb; inbuf / if can't execute ; ; / does it exist? ; jc short np8 ; ; bes 2f / branch if it doesn't ; mov si, offset parp-2 ; mov word ptr [SI], offset shell ; ; mov $shell,parp-2 / does exist, ; ; not executable ; mov ax, offset binpb ; mov word ptr [parp], ax ; ; mov $binpb,parp / so it must be ; sys _exec, shell, si ; ; sys exec; shell; parp-2 / a command file, ; ; / get it with sh /bin/x (if x name of file) ; ----- np8: ;2: mov si, offset msgNoCmd call error ; jsr r5,error / a return for exec ; is the diagnostic ; ; .even mov sp, word ptr [shellarg] sys _exit ; sys exit np9: ;1: ;mov si, offset parp-2 mov si, parp-2 ; 19/06/2022 mov word ptr [SI], offset glob ; mov $glob,parp-2 / prepare to process *,? sys _exec, glob, si ; sys exec; glob; parp-2 ; / execute modified command jmp short np8 ; br 2b delim: test al, al ; 27/06/2014 (EOT signal, COM1/COM2) jz short dlim2 cmp al, 0Dh ; carriage return je short dlim2 ;cmp al, 0Ah ; cmp r0,$'\n / is character a newline ;je short dlim2 ; beq 1f cmp al, '&' ; cmp r0,$'& / is it & je short dlim2 ; beq 1f / yes cmp al, ';' ; cmp r0,$'; / is it ; je short dlim2 ; beq 1f / yes cmp al, '?' ; cmp r0,$'? / is it ? je short dlim1 ; beq 3f ; ;------ 29/05/2022 - unix v2 shell ; (source code from disassembled /bin/sh binary) cmp al, '*' ; cmp r0,$'* / is it * je short dlim1 ; beq 3f cmp al, '[' ; cmp r0,$'[ / is it beginning of character string ; / (for glob) jne short dlim2 ; bne 2f dlim1: ;3: inc byte ptr [glflag] ; inc glflag / ? or * or [ set flag ;2: ;tst (r5)+ / bump to process all except \n,;,& dlim2: ;1: ; zf = 1 if the char is '\n' or ';' or '&' retn ; rts r5 blank: call getc ; jsr pc,getc / get next character cmp al, 20h ; cmp $' ,r0 / leading blanks je short blank ; beq blank / yes, 'squeeze out' cmp al, 8Dh ; 80h + 0Dh ;cmp al, 8Ah ; 80h + 0Ah je short blank ; cmp r0,$200+'\n / new-line preceded by \ ; is translated ; beq blank / into blank ; 19/06/2022 cmp al, 0Ah je short blank ; retn ; rts pc getc: cmp word ptr [param], 0 ; tst param / are we substituting for $n ja short gch3 ; bne 2f/ yes gch0: mov bx, word ptr [inbufp] ; mov inbufp,r1 / no, move normal input pointer to r1 s9: cmp bx, word ptr [einbuf] ; cmp r1,einbuf / end of input line? jb short gch1 ; bne 1f / no call getbuf ; jsr pc,getbuf / yes, put next console line ; in buffer jmp short gch0 ; br getc gch1: ;1: mov al, byte ptr [BX] inc bx ; movb (r1)+,r0 / move byte from input buffer to r0 mov word ptr [inbufp], bx ; mov r1,inbufp / increment routine or al, byte ptr [escap] ;or ax, escap ; bis escap,r0 / if last character was \ this adds ; / 200 to current character ;mov byte ptr [escap], 0 ;mov word ptr [escap], 0 ; clr escap / clear, so escap normally zero cmp al, '\' ; cmp r0,$'\\ / note that \\ is equal \ in as je short gch2 ; beq 1f mov byte ptr [escap], 0 cmp al, '$' ; cmp r0,$'$ / is it $ je short gch5 ; beq 3f / yes retn ; rts pc / no gch2: ;1: mov byte ptr [escap], 80h ;mov word ptr [escap], 128 ; mov $200,escap / mark presence of \ in command line jmp short s9 ;jmp short gch0 ; br getc / get next character gch3: ;2: mov bx, word ptr [param] mov al, byte ptr [BX] ; movb *param,r0 / pick up substitution character ; / put in r0 or al, al jz short gch4 ; beq 1f / if end of substitution arg, branch inc word ptr [param] ; inc param / if not end, set for next character retn ; rts pc / return as though character in ro is normal ; / input gch4: ;1: mov word ptr [param], 0 ; clr param / unset substitution pointer jmp short gch0 ; br getc / get next char in normal input gch5: ;3: call gch0 ;call getc ; jsr pc,getc / get digit after $ sub al, '0' ; sub $'0,r0 / strip off zone bits cmp al, 9 ; cmp r0,$9. / compare with digit 9 jna short gch6 ; blos 1f / less than or equal 9 mov al, 9 ; mov $9.,r0 / if larger than 9, force 9 gch6: ;1: mov bx, word ptr [shellarg] ; mov shellarg,r1 / get pointer to stack for ; / this call of shell cbw ; al->ax (ah=0) inc al ;inc ax ; inc r0 / digit +1 cmp ax, word ptr [BX] ; cmp r0,(r1) / is it less than # of args ; in this call jnb short gch0 ; bge getc / no, ignore it. so this $n is not replaced shl ax, 1 ; asl r0 / yes, multiply by 2 (to skip words) add bx, ax ; add r1,r0 / form pointer to arg pointer (-2) mov ax, word ptr [BX]+2 mov word ptr [param], ax ; mov 2(r0),param / move arg pointer to param jmp short getc ; br getc / go to get substitution arg for $n getbuf: ;mov cx, offset inbuf mov cx, inbuf ; 23/06/2022 ; mov $inbuf,r0 / move input buffer address mov word ptr [inbufp], cx ; mov r0,inbufp / to input buffer pointer mov word ptr [einbuf], cx ; mov r0,einbuf / and initialize pointer to end of ; / character string dec cx ; dec r0 / decrement pointer so can utilize normal ; / 100p starting at 1f ; mov r0,0f / initialize address for reading 1st char mov dx, 1 gbuf0: ;1: inc cx ; inc 0f / this routine filles inbuf with line from ; / console - if there is cnc push cx ; dx = 1 sys _read, 0, och pop cx ;xor bx, bx ; 0 ;sys _read ; sys _read, bx, cx, dx ; bx = 0, dx = 1 ; sys read; 0:0; 1 / read next char into inbuf jc short xit1 ; 29/05/2022 ; bcs xit1 / error exit and ax, ax ; tst r0 / a zero input is end of file jz short xit1 ; beq xit1 / exit inc word ptr [einbuf] ; 08/04/2014 mov al, byte ptr [och] cmp byte ptr [at], 0 jna short gbuf1 cmp al, 8 ; backspace je short gbuf3 cmp al, 127 ; delete je short gbuf6 ; 06/12/2013 gbuf1: ;mov bx, cx ;inc word ptr [einbuf] ; inc einbuf / eventually einbuf points to \n ; / (+1) of this line ;cmp cx, offset inbuf + 256 cmp cx, inbuf+256 ; 19/06/2022 ; cmp 0b,$inbuf+256. / have we exceeded ; input buffer size jnb short xit1 ; bhis xit1 / if so, exit assume some sort of binary ; 27/06/2014 test al, al ; 0, EOT (COM1/COM2) jz short gbuf9 ; 19/06/2022 ; 08/04/2014 cmp al, 0Dh jne short gbuf8 gbuf9: mov bx, word ptr [einbuf] dec bx mov byte ptr [BX], al retn ; 29/05/2022 xit1: sys _exit ; sys exit gbuf8: mov bx, cx mov byte ptr [BX], al ;cmp al, 0Ah ; \n ; cmpb *0b,$'\n / end of line? ;je short gbuf5 ;jne short gbuf1 ; bne 1b / no, go to get next char ;cmp al, 0Dh ; ENTER ;je short gbuf5 cmp byte ptr [at], 0 ; at > 0 --> tty input jna short gbuf0 cmp al, 1Bh ; ESC jne short gbuf2 ;mov ax, offset inbuf mov ax, inbuf ; 19/06/2022 mov word ptr [inbufp], ax mov word ptr [einbuf], ax jmp nl ; cancel current command, new line gbuf2: ; 06/12/2013 cmp byte ptr [at], 0 ja short gbuf7 cmp byte ptr [_echo], 0 jna short gbuf0 gbuf7: push cx ;mov byte ptr [och], al ; DX = 1 sys _write, 1, och ;sys _write, 1, och, 1 ; echo (write char on tty) pop cx jmp short gbuf0 gbuf6: ; DELETE key -> BACKSPACE key ;mov al, 8 mov byte ptr [och], 8 ; 06/12/2013 gbuf3: ; 08/04/2014 dec word ptr [einbuf] ; 12/12/2013 dec cx ;cmp cx, offset inbuf cmp cx, inbuf ; 19/06/2022 jb short gbuf4 dec cx ; 08/04/2014 ;jmp short gbuf2 jmp short gbuf7 gbuf4: ;mov al, 7 mov byte ptr [och], 07h ; beep ; 08/04/2014 ;jmp short gbuf2 jmp short gbuf7 ;gbuf5: ; retn ; rts pc / yes, return ; 29/05/2022 ;xit1: ; sys _exit ; ; sys exit ;----------------------------------------------------------------- ; DATA - initialized data ;----------------------------------------------------------------- ; /// Messages msg_unix_sh: db 0Dh, 0Ah db 'Retro Unix 8086 v1 - shell' ;db 0Dh, 0Ah msgsh_size equ $ - offset msg_unix_sh ;db 0 db '23/06/2022' nextline: db 0Dh, 0Ah, 0 ;Error messages: msgNotFound: db 'Input not found', 0 msgArgCount: db 'Arg count', 0 msgBadDir: db 'Bad directory', 0 msgTryAgain: db 'Try again', 0 msgImbalance: db 22h, 27h, 20h, 'imbalance', 0 msgInputFile: db 'Input file', 0 msgOutputFile: db 'Output file', 0 msgNoCmd: db 'No command', 0 ; /// Commands, files, parameters ; 19/06/2022 FCAT: ; '>>' db 0 ;quest: ;db '?', 0Dh, 0Ah ; prompt: db 0Dh, 0Ah at: db '@ ' ;<@ > p_size equ $ - offset prompt db 0 ; 23/06/2022 (bss, parbuf' word alignment ) ; 06/12/2013 _echo: db 1 qecho: db 'echo', 0 ; qcd: db 'cd', 0 ; ; qchdir: db 'chdir', 0 ; glogin: db 'login', 0 ; shell: db '/bin/sh', 0 ; glob: db '/etc/glob', 0 ; binpb: db '/bin/' ; ;parbuf: ; db 1000 dup(0) ; ; .=.+1000. ;EVEN ; ;.even ;param: ; dw 0 ; ;.=.+2 ;glflag: ; db 0 ; db 0 ; ;.=.+2 ;infile: ; dw 0 ; ; .=.+2 ;outfile: ; dw 0 ; ;.=.+2 ; dw 0 ; ;.=.+2 / room for glob ;parp: ; db 200 dup(0) ; ;.=.+200. ;inbuf: ; db 256 dup(0) ; ;.=.+256. ;;escap: ; ;dw 0 ; ;.=.+2 ;inbufp: ; dw 0 ; ;.=.+2 ;einbuf: ; dw 0 ; ;.=.+2 ;och: ; dw 0 ; ;.=.+2 ;shellarg: ; dw 0 ; ;.=.+2 ;escap: ; db 0 ; ; ; db 0 ;----------------------------------------------------------------- ; bss - uninitialized data ;----------------------------------------------------------------- ; 23/06/2022 ;align 2 bssstart: db 0 UNIX ends end START_CODE ; ---------------------------------------------------------------- ; 29/05/2022 ;----------------------------------------------------------------- ; Original UNIX v2 - shell - PDP-11 assembly source code (sh.s) ;----------------------------------------------------------------- ; UNIX V2 source code: see www.tuhs.org for details. ;----------------------------------------------------------------- ; /// Modified unix v1 shell (sh.s) source code by Erdogan Tan /// ;----------------------------------------------------------------- ; s2.tar.gz - \bin\sh ; ; Source code modified via disassembled unix v2 /bin/sh binary file ; Dissasembler: Hex-Rays Interactive Disassembler (IDA) ; ;/ sh -- command interpreter ; mov sp,r5 ; mov r5,shellarg / save orig sp in shellarg ; cmpb *2(r5),$'- / was this sh called by init or login ; bne 2f / no ; sys intr; 0 / yes, turn off interrupts ; sys quit; 0 ;2: ; sys getuid / who is user ; tst r0 / is it superuser ; bne 2f / no ; movb $'#,at / yes, set new prompt symbol ;2: ; cmp (r5),$1 / tty input? ; ble newline / yes, call with '-' (or with no command ; / file name) ; clr r0 / no, set ttv ; sys close / close it ; mov 4(r5),0f / get new file name ; sys open; 0:..; 0 / open it ; bec 1f / branch if no error ; jsr r5,error / error in file name ; ; .even ; sys exit ;1: ; clr at / clear prompt character, if reading non-tty ; / input file ;newline: ; tst at / is there a prompt symbol ; beq newcom / no ; mov $1,r0 / yes ; sys write; at; 2. / print prompt ;newcom: ; mov shellarg,sp / ; mov $parbuf,r3 / initialize command list area ; mov $parp,r4 / initialize command list pointers ; clr infile / initialize alternate input ; clr outfile / initialize alternate output ; clr glflag / initialize global flag ;newarg: ; jsr pc,blank / squeeze out leading blanks ; jsr r5,delim / is new character a ; \n or & ; br 2f / yes ; mov r3,-(sp) / no, push arg pointer onto stack ; cmp r0,$'< / new input file? ; bne 1f / no ; mov (sp),infile / yes, save arg pointer ; clr (sp) / clear pointer ; br 3f ;1: ; cmp r0,$'> / new output file? ; bne newchar / no ; mov (sp),outfile / yes, save arg pointer ; clr (sp) / clear pointer ; br 3f ;newchar: ; cmp $' ,r0 / is character a blank ; beq 1f / branch if it is (blank as arg separator) ; cmp $'\n+200,r0 / treat \n preceded by \ ; beq 1f / as blank ; jsr pc,putc / put this character in parbuf list ;3: ; jsr pc,getc / get next character ; jsr r5,delim / is char a ; \n or &, ; br 1f / yes ; br newchar / no, start new character tests ;1: ; clrb (r3)+ / end name with \0 when read blank, or ; / delim ; mov (sp)+,(r4)+ / move arg ptr to parp location ; bne 1f / if (sp)=0, in file or out file points to arg ; tst -(r4) / so ignore dummy (0), in pointer list ;1: ; jsr r5,delim / is char a ; \n or &. ; br 2f / yes ; br newarg / no, start newarg processing ;2: ; clr (r4) / \n, &, or ; takes to here (end of arg list) ; / after 'delim' call ; mov r0,-(sp) / save delimiter in stack ; jsr pc,docom / go to exec command in parbuf ; cmpb (sp),$'& / get a new command without wait? ; beq newcom / yes ; tst r1 / was chdir just executed or line ended with ; / ampersand? ; beq 2f / yes ;1: ; sys wait / no, wait for new process to terminate ; / command executed) ; bcs 2f / no, children not previously waited for ; cmp r0,r1 / is this my child ; bne 1b ;2: ; cmp (sp),$'\n / was delimiter a new line ; beq newline / yes ; br newcom / no, pick up next command ;docom: ; sub $parp,r4 / out arg count in r4 ; bne 1f / any arguments? ; clr r1 / no, line ended with ampersand ; rts pc / return from call ;1: ; jsr r5,chcom; qchdir / is command chdir? ; br 2f / command not chdir ; cmp r4,$4 / prepare to exec chdir, 4=arg count x 2 ; beq 3f ; jsr r5,error / go to print error ; ; .even ; br 4f ;3: ; mov parp+2,0f / more directory name to sys coll ; sys chdir; 0:0 / exec chdir ; bec 4f / no error exit ; jsr r5,error / go to print error ; ; .even / this diagnostic ;4: ; clr r1 / set r1 to zero to dkip wait ; rts pc / and return ;2: ; jsr r5,chcom; glogin / is command login? ; br 2f / not loqin, go to fork ; sys exec; parbuf; parp / exec login ; sys exec; binpb; parp / or /bin/login ;2: / no error return?? ; sys fork / generate sh child process for command ; br newproc / exec command with new process ; bec 1f / no error exit, old orocess ; jsr r5,error / go to print error ; ; .even / this diaonostic ; jmp newline / and return for next try ;1: ; mov r0,r1 / save id of child sh ; rts pc / return to "jsr pc, docom" call in parent sh ; ;error: ; movb (r5)+,och / pick up diagnostic character ; beq 1f / 0 is end of line ; mov $1,r0 / set for tty output ; sys write; och; 1 / print it ; br error / continue to get characters ;1: ; inc r5 / inc r5 to point to return ; bic $1,r5 / make it even ; clr r0 / set for input ; sys seek; 0; 2 / exit from runcom. skip to end of ; / input file ; ;/------ 29/05/2022 - unix v2 shell ;/ (source code from disassembled /bin/sh binary) ; rts r5 ; ;chcom: / has no effect if tty input ; mov (r5)+,r1 / glogin gchdir r1, bump r5 ; mov $parbuf,r2 / command address r2 'login' ;1: ; movb (r1)+,r0 / is this command 'chdir' ; cmpb (r2)+,r0 / compare command name byte with 'login' ; / or 'chdir' ; bne 1f / doesn't compare ; tst r0 / is this ; bne 1b / end of names ; tst (r5)+ / yes, bump r5 again to execute login ; / chdir ;1: ; rts r5 / no, return to exec command ; ;putc: ; cmp r0,$'' / single quote? ; beq 1f / yes ; cmp r0,$'" / double quote ; beq 1f / yes ; bic $!177,r0 / no, remove 200, if present ; movb r0,(r3)+ / store character in parbuf ; rts pc ;1: ; mov r0,-(sp) / push quote mark onto stack ;1: ; jsr pc,getc / get a quoted character ; cmp r0,$'\n / is it end or line ; bne 2f / no ; jsr r5,error / yes, indicate missing quote mark ; <"' imbalance\n\0>; .even ; jmp newline / ask for new line ;2: ; cmp r0,(sp) / is this closing quote mark ; beq 1f / yes ; bic $!177,r0 / no, strip off 200 if present ; movb r0,(r3)+ / store quoted character in parbuf ; br 1b / continue ;1: ; tst (sp)+ / pop quote mark off stack ; rts pc / return ; ;/ thp`e new process ; ;newproc: ; mov infile,0f / move pointer to new file name ; beq 1f / branch if no alternate read file given ; tstb *0f ; beq 3f / branch if no file name miven ; clr r0 / set tty input file name ; sys close / close it ; sys open; 0:..; 0 / open new input file for reading ; bcc 1f / branch if input file ok ;3: ; jsr r5,error / file not ok, print error ; ; .even / this diagnostic ; sys exit / terminate this process and make parent sh ;1: ; mov outfile,r2 / more pointer to new file name ; beq 1f / branch if no alternate write file ; cmpb (r2),$'> / is > at beqinning of file name? ; bne 4f / branch if it isn't ; inc r2 / yes, increment pointer ; mov r2,0f ; sys open; 0:..; 1 / open file for writing ; bec 3f / if no error ;4: ; mov r2,0f ; sys creat; 0:..; 17 / create new file with this name ; bec 3f / branch if no error ;2: ; jsr r5,error ; ; .even ; sys exit ;3: ; sys close / close the new write file ; mov r2,0f / move new name to open ; mov $1,r0 / set ttv file name ; sys close / close it ; sys open; 0:..; 1 / open new output file, it now has ; / file descriptor 1 ; sys seek; 0; 2 / set pointer to current end of file ;1: ; tst glflag / was *, ? or [ encountered? ; bne 1f / yes ; sys exec; parbuf; parp / no, execute this commend ; sys exec; binpb; parp / or /bin/this command ; ;/------ 29/05/2022 - unix v2 shell ;/ (source code from disassembled /bin/sh binary) ;/ following part is not existing in v2 shell ; ;/2: ;/ sys stat; binpb; inbuf / if can't execute does it ;/ / exist? ;/ bes 2f / branch if it doesn't ;/ mov $shell,parp-2 / does exist, not executable ;/ mov $binpb,parp / so it must be ;/ sys exec; shell; parp-2 / a command file, get it with ;/ / sh /bin/x (if x name of file) ;/------ ;2: ; jsr r5,error / a return for exec is the diagnostic ; ; .even ; sys exit ;1: ; mov $glob,parp-2 / prepare to process *,? ; sys exec; glob; parp-2 / execute modified command ; br 2b ; ;delim: ; cmp r0,$'\n / is character a newline ; beq 1f ; cmp r0,$'& / is it & ; beq 1f / yes ; cmp r0,$'; / is it ; ; beq 1f / yes ; cmp r0,$'? / is it ? ; beq 3f ; ;/------ 29/05/2022 - unix v2 shell ;/ (source code from disassembled /bin/sh binary) ; cmp r0,$'* / is it * ; beq 3f ; ; cmp r0,$'[ / is it beginning of character string ; / (for glob) ; bne 2f ;3: ; inc glflag / ? or * or [ set flag ;2: ; tst (r5)+ / bump to process all except \n,;,& ;1: ; rts r5 ; ;blank: ; jsr pc,getc / get next character ; cmp $' ,r0 / leading blanks ; beq blank / yes, 'squeeze out' ; cmp r0,$200+'\n / new-line preceded by \ is translated ; beq blank / into blank ; rts pc ;getc: ; tst param / are we substituting for $n ; bne 2f/ yes ; mov inbufp,r1 / no, move normal input pointer to r1 ; cmp r1,einbuf / end of input line? ; bne 1f / no ; jsr pc,getbuf / yes, put next console line in buffer ; br getc ;1: ; movb (r1)+,r0 / move byte from input buffer to r0 ; mov r1,inbufp / increment routine ; bis escap,r0 / if last character was \ this adds ; / 200 to current character ; clr escap / clear, so escap normally zero ; cmp r0,$'\\ / note that \\ is equal \ in as ; beq 1f ; cmp r0,$'$ / is it $ ; beq 3f / yes ; rts pc / no ;1: ; mov $200,escap / mark presence of \ in command line ; br getc / get next character ;2: ; movb *param,r0 / pick up substitution character put in ; / r0 ; beq 1f / if end of substitution arg, branch ; inc param / if not end, set for next character ; rts pc / return as though character in ro is normal ; / input ;1: ; clr param / unset substitution pointer ; br getc / get next char in normal input ;3: ; jsr pc,getc / get digit after $ ; sub $'0,r0 / strip off zone bits ; cmp r0,$9. / compare with digit 9 ; blos 1f / less than or equal 9 ; mov $9.,r0 / if larger than 9, force 9 ;1: ; mov shellarg,r1 / get pointer to stack for ; / this call of shell ; inc r0 / digit +1 ; cmp r0,(r1) / is it less than # of args in this call ; bge getc / no, ignore it. so this $n is not replaced ; asl r0 / yes, multiply by 2 (to skip words) ; add r1,r0 / form pointer to arg pointer (-2) ; mov 2(r0),param / move arg pointer to param ; br getc / go to get substitution arg for $n ;getbuf: ; mov $inbuf,r0 / move input buffer address ; mov r0,inbufp / to input buffer pointer ; mov r0,einbuf / and initialize pointer to end of ; / character string ; dec r0 / decrement pointer so can utilize normal ; / 100p starting at 1f ; mov r0,0f / initialize address for reading 1st char ;1: ; inc 0f / this routine filles inbuf with line from ; / console - if there is cnc ; clr r0 / set for tty input ; sys read; 0:0; 1 / read next char into inbuf ; bcs xit1 / error exit ; tst r0 / a zero input is end of file ; beq xit1 / exit ; inc einbuf / eventually einbuf points to \n ; / (+1) of this line ; cmp 0b,$inbuf+256. / have we exceeded input buffer size ; bhis xit1 / if so, exit assume some sort of binary ; cmpb *0b,$'\n / end of line? ; bne 1b / no, go to get next char ; rts pc / yes, return ; ;xit1: ; sys exit ; ;quest: ; ; ;at: ; <@ > ; ;qchdir: ; ;glogin: ; ;shell: ; ;glob: ; ;binpb: ; ;parbuf: .=.+1000. ; .even ;param: .=.+2 ;glflag: .=.+2 ;infile: .=.+2 ;outfile:.=.+2 ; .=.+2 / room for glob ;parp: .=.+200. ;inbuf: .=.+256. ;escap: .=.+2 ;inbufp: .=.+2 ;einbuf: .=.+2 ;och: .=.+2 ;shellarg:.=.+2 ; 29/05/2022 ;----------------------------------------------------------------- ; Original UNIX v1 - shell - PDP-11 assembly source code (sh.s) ;----------------------------------------------------------------- ; UNIX V1 source code: see www.tuhs.org for details. ;----------------------------------------------------------------- ; PreliminaryUnixImplementationDocument_Jun72.pdf - Section: E11 ;----------------------------------------------------------------- ; https://minnie.tuhs.org/cgi-bin/utree.pl?file=V1/sh.s ; ;/ sh -- command interpreter ; mov sp,r5 ; mov r5,shellarg / save orig sp in shellarg ; cmpb *2(r5),$'- / was this sh called by init or login ; bne 2f / no ; sys intr; 0 / yes, turn off interrupts ; sys quit; 0 ;2: ; sys getuid / who is user ; tst r0 / is it superuser ; bne 2f / no ; movb $'#,at / yes, set new prompt symbol ;2: ; cmp (r5),$1 / tty input? ; ble newline / yes, call with '-' (or with no command ; / file name) ; clr r0 / no, set ttv ; sys close / close it ; mov 4(r5),0f / get new file name ; sys open; 0:..; 0 / open it ; bec 1f / branch if no error ; jsr r5,error / error in file name ; ; .even ; sys exit ;1: ; clr at / clear prompt character, if reading non-tty ; / input file ;newline: ; tst at / is there a prompt symbol ; beq newcom / no ; mov $1,r0 / yes ; sys write; at; 2. / print prompt ;newcom: ; mov shellarg,sp / ; mov $parbuf,r3 / initialize command list area ; mov $parp,r4 / initialize command list pointers ; clr infile / initialize alternate input ; clr outfile / initialize alternate output ; clr glflag / initialize global flag ;newarg: ; jsr pc,blank / squeeze out leading blanks ; jsr r5,delim / is new character a ; \n or & ; br 2f / yes ; mov r3,-(sp) / no, push arg pointer onto stack ; cmp r0,$'< / new input file? ; bne 1f / no ; mov (sp),infile / yes, save arg pointer ; clr (sp) / clear pointer ; br 3f ;1: ; cmp r0,$'> / new output file? ; bne newchar / no ; mov (sp),outfile / yes, save arg pointer ; clr (sp) / clear pointer ; br 3f ;newchar: ; cmp $' ,r0 / is character a blank ; beq 1f / branch if it is (blank as arg separator) ; cmp $'\n+200,r0 / treat \n preceded by \ ; beq 1f / as blank ; jsr pc,putc / put this character in parbuf list ;3: ; jsr pc,getc / get next character ; jsr r5,delim / is char a ; \n or &, ; br 1f / yes ; br newchar / no, start new character tests ;1: ; clrb (r3)+ / end name with \0 when read blank, or ; / delim ; mov (sp)+,(r4)+ / move arg ptr to parp location ; bne 1f / if (sp)=0, in file or out file points to arg ; tst -(r4) / so ignore dummy (0), in pointer list ;1: ; jsr r5,delim / is char a ; \n or &. ; br 2f / yes ; br newarg / no, start newarg processing ;2: ; clr (r4) / \n, &, or ; takes to here (end of arg list) ; / after 'delim' call ; mov r0,-(sp) / save delimiter in stack ; jsr pc,docom / go to exec command in parbuf ; cmpb (sp),$'& / get a new command without wait? ; beq newcom / yes ; tst r1 / was chdir just executed or line ended with ; / ampersand? ; beq 2f / yes ;1: ; sys wait / no, wait for new process to terminate ; / command executed) ; bcs 2f / no, children not previously waited for ; cmp r0,r1 / is this my child ; bne 1b ;2: ; cmp (sp),$'\n / was delimiter a new line ; beq newline / yes ; br newcom / no, pick up next command ;docom: ; sub $parp,r4 / out arg count in r4 ; bne 1f / any arguments? ; clr r1 / no, line ended with ampersand ; rts pc / return from call ;1: ; jsr r5,chcom; qchdir / is command chdir? ; br 2f / command not chdir ; cmp r4,$4 / prepare to exec chdir, 4=arg count x 2 ; beq 3f ; jsr r5,error / go to print error ; ; .even ; br 4f ;3: ; mov parp+2,0f / more directory name to sys coll ; sys chdir; 0:0 / exec chdir ; bec 4f / no error exit ; jsr r5,error / go to print error ; ; .even / this diagnostic ;4: ; clr r1 / set r1 to zero to dkip wait ; rts pc / and return ;2: ; jsr r5,chcom; glogin / is command login? ; br 2f / not loqin, go to fork ; sys exec; parbuf; parp / exec login ; sys exec; binpb; parp / or /bin/login ;2: / no error return?? ; sys fork / generate sh child process for command ; br newproc / exec command with new process ; bec 1f / no error exit, old orocess ; jsr r5,error / go to print error ; ; .even / this diaonostic ; jmp newline / and return for next try ;1: ; mov r0,r1 / save id of child sh ; rts pc / return to "jsr pc, docom" call in parent sh ; ;error: ; movb (r5)+,och / pick up diagnostic character ; beq 1f / 0 is end of line ; mov $1,r0 / set for tty output ; sys write; och; 1 / print it ; br error / continue to get characters ;1: ; inc r5 / inc r5 to point to return ; bic $1,r5 / make it even ; clr r0 / set for input ; sys seek; 0; 2 / exit from runcom. skip to end of ; / input file ;chcom: / has no effect if tty input ; mov (r5)+,r1 / glogin gchdir r1, bump r5 ; mov $parbuf,r2 / command address r2 'login' ;1: ; movb (r1)+,r0 / is this command 'chdir' ; cmpb (r2)+,r0 / compare command name byte with 'login' ; / or 'chdir' ; bne 1f / doesn't compare ; tst r0 / is this ; bne 1b / end of names ; tst (r5)+ / yes, bump r5 again to execute login ; / chdir ;1: ; rts r5 / no, return to exec command ; ;putc: ; cmp r0,$'' / single quote? ; beq 1f / yes ; cmp r0,$'" / double quote ; beq 1f / yes ; bic $!177,r0 / no, remove 200, if present ; movb r0,(r3)+ / store character in parbuf ; rts pc ;1: ; mov r0,-(sp) / push quote mark onto stack ;1: ; jsr pc,getc / get a quoted character ; cmp r0,$'\n / is it end or line ; bne 2f / no ; jsr r5,error / yes, indicate missing quote mark ; <"' imbalance\n\0>; .even ; jmp newline / ask for new line ;2: ; cmp r0,(sp) / is this closing quote mark ; beq 1f / yes ; bic $!177,r0 / no, strip off 200 if present ; movb r0,(r3)+ / store quoted character in parbuf ; br 1b / continue ;1: ; tst (sp)+ / pop quote mark off stack ; rts pc / return ; ;/ thp`e new process ; ;newproc: ; mov infile,0f / move pointer to new file name ; beq 1f / branch if no alternate read file given ; tstb *0f ; beq 3f / branch if no file name miven ; clr r0 / set tty input file name ; sys close / close it ; sys open; 0:..; 0 / open new input file for reading ; bcc 1f / branch if input file ok ;3: ; jsr r5,error / file not ok, print error ; ; .even / this diagnostic ; sys exit / terminate this process and make parent sh ;1: ; mov outfile,r2 / more pointer to new file name ; beq 1f / branch if no alternate write file ; cmpb (r2),$'> / is > at beqinning of file name? ; bne 4f / branch if it isn't ; inc r2 / yes, increment pointer ; mov r2,0f ; sys open; 0:..; 1 / open file for writing ; bec 3f / if no error ;4: ; mov r2,0f ; sys creat; 0:..; 17 / create new file with this name ; bec 3f / branch if no error ;2: ; jsr r5,error ; ; .even ; sys exit ;3: ; sys close / close the new write file ; mov r2,0f / move new name to open ; mov $1,r0 / set ttv file name ; sys close / close it ; sys open; 0:..; 1 / open new output file, it now has ; / file descriptor 1 ; sys seek; 0; 2 / set pointer to current end of file ;1: ; tst glflag / was *, ? or [ encountered? ; bne 1f / yes ; sys exec; parbuf; parp / no, execute this commend ; sys exec; binpb; parp / or /bin/this command ;2: ; sys stat; binpb; inbuf / if can't execute does it ; / exist? ; bes 2f / branch if it doesn't ; mov $shell,parp-2 / does exist, not executable ; mov $binpb,parp / so it must be ; sys exec; shell; parp-2 / a command file, get it with ; / sh /bin/x (if x name of file) ;2: ; jsr r5,error / a return for exec is the diagnostic ; ; .even ; sys exit ;1: ; mov $glob,parp-2 / prepare to process *,? ; sys exec; glob; parp-2 / execute modified command ; br 2b ; ;delim: ; cmp r0,$'\n / is character a newline ; beq 1f ; cmp r0,$'& / is it & ; beq 1f / yes ; cmp r0,$'; / is it ; ; beq 1f / yes ; cmp r0,$'? / is it ? ; beq 3f ; cmp r0,$'[ / is it beginning of character string ; / (for glob) ; bne 2f ;3: ; inc glflag / ? or * or [ set flag ;2: ; tst (r5)+ / bump to process all except \n,;,& ;1: ; rts r5 ; ;blank: ; jsr pc,getc / get next character ; cmp $' ,r0 / leading blanks ; beq blank / yes, 'squeeze out' ; cmp r0,$200+'\n / new-line preceded by \ is translated ; beq blank / into blank ; rts pc ;getc: ; tst param / are we substituting for $n ; bne 2f/ yes ; mov inbufp,r1 / no, move normal input pointer to r1 ; cmp r1,einbuf / end of input line? ; bne 1f / no ; jsr pc,getbuf / yes, put next console line in buffer ; br getc ;1: ; movb (r1)+,r0 / move byte from input buffer to r0 ; mov r1,inbufp / increment routine ; bis escap,r0 / if last character was \ this adds ; / 200 to current character ; clr escap / clear, so escap normally zero ; cmp r0,$'\\ / note that \\ is equal \ in as ; beq 1f ; cmp r0,$'$ / is it $ ; beq 3f / yes ; rts pc / no ;1: ; mov $200,escap / mark presence of \ in command line ; br getc / get next character ;2: ; movb *param,r0 / pick up substitution character put in ; / r0 ; beq 1f / if end of substitution arg, branch ; inc param / if not end, set for next character ; rts pc / return as though character in ro is normal ; / input ;1: ; clr param / unset substitution pointer ; br getc / get next char in normal input ;3: ; jsr pc,getc / get digit after $ ; sub $'0,r0 / strip off zone bits ; cmp r0,$9. / compare with digit 9 ; blos 1f / less than or equal 9 ; mov $9.,r0 / if larger than 9, force 9 ;1: ; mov shellarg,r1 / get pointer to stack for ; / this call of shell ; inc r0 / digit +1 ; cmp r0,(r1) / is it less than # of args in this call ; bge getc / no, ignore it. so this $n is not replaced ; asl r0 / yes, multiply by 2 (to skip words) ; add r1,r0 / form pointer to arg pointer (-2) ; mov 2(r0),param / move arg pointer to param ; br getc / go to get substitution arg for $n ;getbuf: ; mov $inbuf,r0 / move input buffer address ; mov r0,inbufp / to input buffer pointer ; mov r0,einbuf / and initialize pointer to end of ; / character string ; dec r0 / decrement pointer so can utilize normal ; / 100p starting at 1f ; mov r0,0f / initialize address for reading 1st char ;1: ; inc 0f / this routine filles inbuf with line from ; / console - if there is cnc ; clr r0 / set for tty input ; sys read; 0:0; 1 / read next char into inbuf ; bcs xit1 / error exit ; tst r0 / a zero input is end of file ; beq xit1 / exit ; inc einbuf / eventually einbuf points to \n ; / (+1) of this line ; cmp 0b,$inbuf+256. / have we exceeded input buffer size ; bhis xit1 / if so, exit assume some sort of binary ; cmpb *0b,$'\n / end of line? ; bne 1b / no, go to get next char ; rts pc / yes, return ; ;xit1: ; sys exit ; ;quest: ; ; ;at: ; <@ > ; ;qchdir: ; ;glogin: ; ;shell: ; ;glob: ; ;binpb: ; ;parbuf: .=.+1000. ; .even ;param: .=.+2 ;glflag: .=.+2 ;infile: .=.+2 ;outfile:.=.+2 ; .=.+2 / room for glob ;parp: .=.+200. ;inbuf: .=.+256. ;escap: .=.+2 ;inbufp: .=.+2 ;einbuf: .=.+2 ;och: .=.+2 ;shellarg:.=.+2