mirror of
https://github.com/DoctorWkt/pdp7-unix.git
synced 2026-05-05 07:33:37 +00:00
philbudne
257
src/other/pbsh.s
257
src/other/pbsh.s
@@ -37,9 +37,12 @@ maxargs=8
|
||||
|
||||
newline:
|
||||
lac d1; sys write; prompt; 1 " output prompt
|
||||
jms rline " read line into ibuf
|
||||
lac iipt
|
||||
dac ipt
|
||||
jms rline " read (edited) line into lbuf
|
||||
lac ilpt
|
||||
dac lpt " reset line pointer
|
||||
|
||||
" parse new command from current input line
|
||||
" (after ';' or '&')
|
||||
newcom:
|
||||
dzm char " clear saved char
|
||||
dzm infile " clear input redirect file name
|
||||
@@ -68,12 +71,12 @@ newarg:
|
||||
|
||||
jms blank " skip whitespace
|
||||
jms delim " command sep?
|
||||
jmp eol " yes
|
||||
jmp eoc " yes
|
||||
sad lt " input redirect?
|
||||
jmp redirin
|
||||
jmp redirin " yes
|
||||
sad gt " output redirect?
|
||||
jmp redirout
|
||||
jmp 3f
|
||||
jmp redirout " yes
|
||||
jmp savechar " no: save as filename
|
||||
|
||||
redirin: " saw <
|
||||
dac redirect " flag redirect
|
||||
@@ -87,40 +90,43 @@ redirout: " saw >
|
||||
dac opt
|
||||
" fall
|
||||
|
||||
newchar:
|
||||
newchar: " loop reading a file name
|
||||
jms getc
|
||||
sad o40 " space?
|
||||
jmp eoname " yes
|
||||
jms delim
|
||||
jmp eoname
|
||||
3: jms putc " save
|
||||
jms delim " no: end of line?
|
||||
jmp eoname " yes
|
||||
savechar:
|
||||
jms putc " no: save
|
||||
isz bcount " loop unless full
|
||||
jmp newchar
|
||||
|
||||
" here after 8 chars: discard until terminator seen
|
||||
discard:
|
||||
jms getc
|
||||
1: jms getc
|
||||
jms delim " end of line?
|
||||
jmp eoname
|
||||
jmp 2f
|
||||
sad o40
|
||||
jmp eoname
|
||||
jmp discard
|
||||
jmp 2f
|
||||
jmp 1b
|
||||
|
||||
2:
|
||||
dac char " save terminator
|
||||
jmp full
|
||||
|
||||
" name ended (short) with whitespace or delim
|
||||
" pad out last name to 8 with spaces
|
||||
" XXX check if ANYTHING read
|
||||
eoname:
|
||||
dac char " save terminator
|
||||
1: lac o40
|
||||
jms putc " no: copy into argv
|
||||
jms putc " copy into argv
|
||||
isz bcount " loop until full
|
||||
jmp 1b
|
||||
|
||||
" saw end of name
|
||||
2: lac redirect
|
||||
full:
|
||||
lac redirect
|
||||
sza
|
||||
jmp 2f " last name was a redirect file, skip increment
|
||||
|
||||
" file was not a redirection:
|
||||
lac argc " increment argc
|
||||
tad d4
|
||||
dac argc
|
||||
@@ -131,31 +137,31 @@ eoname:
|
||||
2:
|
||||
dzm redirect " clear redirect flag
|
||||
lac nextarg
|
||||
dac opt
|
||||
dac opt " set output pointer
|
||||
|
||||
lac char
|
||||
jms delim
|
||||
jmp eol
|
||||
lac char " get terminator
|
||||
jms delim " end of command?
|
||||
jmp eoc " yes
|
||||
|
||||
lac argc
|
||||
sad maxargwords
|
||||
skp
|
||||
jmp newarg
|
||||
lac argc " another arg
|
||||
sad maxargwords " full up?
|
||||
skp " yes
|
||||
jmp newarg " no: get another
|
||||
|
||||
" too many args, (complain?). for now eat rest of line
|
||||
" too many args
|
||||
4: jms getc
|
||||
jms delim
|
||||
skp
|
||||
jmp 4b
|
||||
lac d1; sys write; toomany; ltoomany
|
||||
jmp newline
|
||||
jmp newline " ignore rest of line
|
||||
|
||||
" here at end of line
|
||||
eol:
|
||||
sad delimchar " save eol character
|
||||
" here at end of command
|
||||
eoc:
|
||||
dac delimchar " save command delimiter
|
||||
lac argc " check for empty command line
|
||||
sna " get anything?
|
||||
jmp 2f " no, go back for another
|
||||
jmp nextcmd " no, go back for another
|
||||
|
||||
" check for built-in "chdir" command
|
||||
lac argv0
|
||||
@@ -170,40 +176,37 @@ eol:
|
||||
sad chdirstr+2
|
||||
jmp changedir
|
||||
|
||||
1:
|
||||
" comment these out to test "exec" w/o fork
|
||||
sys fork
|
||||
" here to execute command (not a builtin)
|
||||
1: sys fork
|
||||
jmp parent
|
||||
|
||||
child: " debug symbol
|
||||
sys open; argv0; 0 " try cwd (no link required)
|
||||
sma
|
||||
jmp 1f
|
||||
" jmp cmderr
|
||||
sma " error?
|
||||
jmp 1f " no
|
||||
|
||||
sys unlink; exectemp " remove old temp file, if any
|
||||
sys link; system; argv0; exectemp
|
||||
sys link; system; argv0; argv0
|
||||
spa
|
||||
jmp cmderr
|
||||
sys open; exectemp; 0
|
||||
jmp cmderr
|
||||
sys open; argv0; 0
|
||||
spa
|
||||
jmp cmderr
|
||||
jmp cmderr
|
||||
dac cmdfd
|
||||
sys unlink; exectemp
|
||||
sys unlink; argv0
|
||||
skp
|
||||
|
||||
1: dac cmdfd " save command file descriptor
|
||||
cla " check for input redirection
|
||||
sad infile " input redirct?
|
||||
jmp 1f " no
|
||||
sys close " close fd 0
|
||||
sys open; infile; 0 " open redirected
|
||||
spa sna
|
||||
sys open; infile; 0 " open new stdin
|
||||
spa
|
||||
jmp inerror
|
||||
cla
|
||||
1: sad outfile " output redirec?
|
||||
1: sad outfile " output redirect?
|
||||
jmp exec " no
|
||||
lac d1; sys close " close fd 1
|
||||
lac o17; sys creat; outfile " open output redirect
|
||||
lac o17; sys creat; outfile " open new stdout
|
||||
spa
|
||||
jmp outerror
|
||||
|
||||
@@ -225,7 +228,7 @@ exec:
|
||||
|
||||
" copied up to bootloc in high memory (below argc)
|
||||
boot:
|
||||
sys read; userbase; userlen " read executable in
|
||||
sys read; userbase; userlen " read executable in (check for non-zero ret?)
|
||||
lacq " Get the fd back and close the file
|
||||
sys close " close command file
|
||||
jmp userbase " and jump to the beginning of the executable
|
||||
@@ -245,31 +248,34 @@ error: " error in child: filename pointer in AC
|
||||
lac d1; sys write; 1: 0; 4
|
||||
lac d1; sys write; qmnl; 1
|
||||
lac d2; sys close " close executable, if any
|
||||
sys exit
|
||||
sys exit " performs implicit rmes
|
||||
|
||||
" chdir command: executed in shell process
|
||||
" takes a series of directory names to chdir to in turn
|
||||
changedir:
|
||||
" XXX check if argc == 4 (no directories) and complain??
|
||||
lac argc
|
||||
sad d4
|
||||
jmp qm " need at least one arg!
|
||||
lac argv0p
|
||||
skp
|
||||
1: lac 0f " increment argvp
|
||||
1: lac 0f " increment dir pointer
|
||||
tad d4
|
||||
dac 0f
|
||||
-4 " decrement argc
|
||||
tad argc
|
||||
dac argc
|
||||
sna " done?
|
||||
jmp 2f " yes: join parent code
|
||||
jmp nextcmd " yes: join parent code
|
||||
sys chdir; 0:0
|
||||
sma " error?
|
||||
jmp 1b " no: look for another directory
|
||||
|
||||
" chdir call failed
|
||||
lac 0b
|
||||
dac 0f
|
||||
lac d1; sys write; 0:0; 4
|
||||
lac d1; sys write; qmnl; 1
|
||||
jmp 2f " join parent code
|
||||
|
||||
lac 0b " chdir failed: get offending name
|
||||
dac 0f " store for write
|
||||
lac d1; sys write; 0:0; 4 " complain
|
||||
qm:lac d1; sys write; qmnl; 1
|
||||
jmp nextcmd " join parent code
|
||||
|
||||
" here in parent, child pid in AC
|
||||
parent:
|
||||
@@ -290,9 +296,11 @@ parent:
|
||||
jmp newcom " yes: go back without wait
|
||||
lac pid " no: get pid
|
||||
sys smes " hang until child exits
|
||||
2: lac delimchar
|
||||
nop
|
||||
nextcmd:
|
||||
lac delimchar
|
||||
sad o73 " semi?
|
||||
jmp newcom " yes: look for another command w/o prompt
|
||||
jmp newcom " yes: look for another command on line
|
||||
jmp newline " no: output prompt
|
||||
|
||||
" ================
|
||||
@@ -318,46 +326,70 @@ delim: 0
|
||||
isz delim " ran the gauntlet: skip home
|
||||
jmp delim i
|
||||
|
||||
" get character from ibuf
|
||||
" get character from lbuf
|
||||
getc: 0
|
||||
lac ipt i " fetch char
|
||||
isz ipt " increment pointer
|
||||
lac lpt i " fetch char from line buffer
|
||||
isz lpt " increment pointer
|
||||
jmp getc i
|
||||
|
||||
" from init.s rline: read line from tty into ibuf
|
||||
" from init.s rline: read line into lbuf with editing
|
||||
" (store one character per word)
|
||||
rline: 0
|
||||
law ibuf-1 " Store ibuf pointer in location 8
|
||||
law lbuf-1 " pointer in location 8
|
||||
dac 8
|
||||
1:
|
||||
cla; sys read; char; 1 " Read in one character from stdin
|
||||
sna " read ok?
|
||||
jmp quit " no
|
||||
lac char
|
||||
lrss 9 " Get it and shift down 9 bits
|
||||
sad o100 " '@' (kill) character?
|
||||
jmp rline+1 " yes: start from scratch
|
||||
sad o43 " '#' (erase) character?
|
||||
jmp 2f " yes: handle below
|
||||
|
||||
dac 8 i " Store the character in the buffer
|
||||
sad o12 " Newline?
|
||||
jmp rline i " yes: return
|
||||
jmp 1b " no: keep going
|
||||
1: jms readc
|
||||
jmp quit " EOF
|
||||
sad o100 " '@' (kill) character?
|
||||
jmp rline+1 " yes: start from scratch
|
||||
sad o43 " '#' (erase) character?
|
||||
jmp 2f " yes: handle below
|
||||
dac 8 i " Store the character in the buffer
|
||||
sad o12 " Newline?
|
||||
jmp rline i " yes: return
|
||||
jmp 1b " no: keep going
|
||||
2:
|
||||
law ibuf-1 " # handling. Do nothing if at start of the buffer
|
||||
sad 8
|
||||
jmp 1b " and loop back
|
||||
-1
|
||||
tad 8 " Otherwise, move the pointer in location 8 back one
|
||||
law lbuf-1 " # (erase) handling
|
||||
sad 8 " at start?
|
||||
jmp 1b " yes: noop, loop back
|
||||
-1 " no: decrement poiner
|
||||
tad 8
|
||||
dac 8
|
||||
jmp 1b " and loop back
|
||||
jmp 1b
|
||||
|
||||
quit:
|
||||
lac d1; sys smes " wake up init
|
||||
sys exit
|
||||
|
||||
" copied from cat.s:
|
||||
" copied from cat.s
|
||||
|
||||
" was "getc"
|
||||
readc: 0
|
||||
lac ipt " Load the pointer to the next word in the buffer
|
||||
sad eipt
|
||||
jmp 1f " We've reached the end of the buffer, so read more
|
||||
dac 2f " Save the pointer
|
||||
add o400000 " Flip the msb and save into ipt
|
||||
dac ipt
|
||||
ral " Move the msb into the link register
|
||||
lac 2f i " Load the word from the buffer
|
||||
szl " Skip if this is the second character in the word
|
||||
lrss 9 " It's the first char, shift down the top character
|
||||
and o177 " Keep the lowest 7 bits
|
||||
sna
|
||||
jmp readc+1 " Skip a NUL characters and read another one
|
||||
isz readc " give skip return
|
||||
jmp readc i " Return the character from the subroutine
|
||||
1:
|
||||
cla " Buffer is empty, read 64 chars from stdin
|
||||
sys read; iipt+1; 64
|
||||
sna
|
||||
jmp readc i " No characters read: return without skip
|
||||
tad iipt " Add the word count to the base of the buffer
|
||||
dac eipt " and store in the end buffer pointer
|
||||
lac iipt " Reset the ipt to the base of the buffer
|
||||
dac ipt
|
||||
jmp readc+1 " and loop back to get one character
|
||||
|
||||
putc: 0
|
||||
and o177 " Keep the lowest 7 bits and save into 2f+1
|
||||
dac 2f+1
|
||||
@@ -378,17 +410,22 @@ putc: 0
|
||||
jmp putc i " No, so return (more room still in the buffer)
|
||||
|
||||
2: 0;0 " pointer, char
|
||||
ipt: 0 " Current input buffer base
|
||||
eipt: 0 " Pointer to end of data read in input buffer
|
||||
iipt: .+1; .=.+64 " 64 word input buffer and pointer to it
|
||||
" end from cat.s
|
||||
|
||||
" literals
|
||||
d1: 1
|
||||
d2: 2
|
||||
o4:d4: 4
|
||||
dm8: -8
|
||||
o12: 012 " newline
|
||||
o17: 017
|
||||
o40: 040 " space
|
||||
o43: 043 " #
|
||||
o46: 046 " ampersand
|
||||
o73: 046 " semi
|
||||
o73: 073 " semi
|
||||
o74:lt: 074 " <
|
||||
o76:gt: 076 " >
|
||||
o100: 0100 " @
|
||||
@@ -401,9 +438,6 @@ qmnl: <? 012 " question mark, newline
|
||||
system:
|
||||
<sy>;<st>;<em>; 040040
|
||||
|
||||
exectemp:
|
||||
<ex>;<ec>;<te>;<mp> " temporary link for file being exec'ed
|
||||
|
||||
chdirstr:
|
||||
<ch>;<di>;<r 040
|
||||
|
||||
@@ -419,7 +453,7 @@ argcptr: argc
|
||||
infilep: infile
|
||||
outfilep: outfile
|
||||
|
||||
iipt: ibuf
|
||||
ilpt: lbuf " initial line buffer pointer
|
||||
iopt:argv0p: argv0 " initial value for nextarg, opt
|
||||
|
||||
" ################ variables
|
||||
@@ -429,9 +463,9 @@ prompt: <@ 040 " v1 prompt!
|
||||
redirect: .=.+1 " last file was a redirect (lt or gt)
|
||||
nextarg: .=.+1 " next slot in argv to fill
|
||||
bcount: .=.+1 " byte counter for current filename
|
||||
opt: .=.+1 " "output pointer" (may point to in/outfile or into argv)
|
||||
opt: .=.+1 " "output pointer" (in/outfile or into argv)
|
||||
delimchar: .=.+1 " character that terminated line
|
||||
char: .=.+1 " char that terminated word
|
||||
char: .=.+1 " char that terminated word (merge w/ delimchar?)
|
||||
|
||||
outfile: .=.+4 " buffer for output redirect file name
|
||||
infile: .=.+4 " buffer for input redirect file name
|
||||
@@ -439,17 +473,20 @@ pid: .=.+1 " "other" pid
|
||||
cmdfd: .=.+1 " fd for executable
|
||||
bootcount: .=.+1 " loop count for "boot" copy
|
||||
|
||||
ipt: .=.+1 " input buf pointer
|
||||
ibuf: " input line stored here, one character per word
|
||||
lpt: .=.+1 " line buf pointer
|
||||
lbuf: " edited line, one char per word
|
||||
|
||||
" enter addresses into namelist:
|
||||
.=017777 " last word points to argc + argv data
|
||||
argptr:
|
||||
|
||||
.=argptr-maxargs-maxargs-maxargs-maxargs-1 " argc followed by argv
|
||||
argc: .=.+1
|
||||
argv0: " 4 word blocks following argc
|
||||
|
||||
" "bootstrap" (reads executable into userbase) copied JUST below argc
|
||||
.=argc-bootlen
|
||||
bootloc:
|
||||
|
||||
userbase=010000 " user starts at 4K
|
||||
argptr=017777 " last word points to argc + argv data
|
||||
argc=argptr-maxargs-maxargs-maxargs-maxargs-1 " argc followed by argv
|
||||
|
||||
" arguments in 4 word blocks follow argc
|
||||
argv0=argc+1
|
||||
|
||||
" "bootstrap" (reads executable into userbase) JUST below argc
|
||||
bootloc=argc-bootlen " location of bootstrap
|
||||
|
||||
userlen=bootloc-userbase " max executable
|
||||
|
||||
Reference in New Issue
Block a user