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Merge branch 'master' of https://github.com/DoctorWkt/pdp7-unix

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This commit is contained in:
Warren Toomey 2016-03-08 16:43:47 +10:00
commit e9c8aae876
7 changed files with 190 additions and 583 deletions
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1
scans/as.s
View File

@ -148,6 +148,7 @@ init: 0
dac fname
-1
dac eofflg
jms nextfil
jms ioinit
dzm savchr
dzm comflg

250
src/other/pbsh.s
View File

@ -1,53 +1,73 @@
" -*-fundamental-*-
" sh -- a shell
" pbsh -- a shell
" started by p budne 3/4/2016
" with code from cat.s, init.s, and looking at the v1 (pdp-11) shell
" with code from init.s, cat.s and looking at the v1 (pdp-11) shell
" XXX cat.s seems to write error output on fd 8
" In particular, the newline/newcom/newarg/newchar processing loop(s)
" are copied from the v1 shell:
" redirection must occur at the start of a name (after whitespace)
start:
" XXX take command line argument (script file to open), suppress prompt??
" NOTE!!! v0 init.s doesn't set up the argv at the top of memory,
" so the v0 shell may not have taken command line arguments!!!
" if non-interactive, "dzm prompt", jump to newcom
" includes ';' and '&' (unknown if available in v0 shell)
" does NOT (yet) include quoting (backslash or single quote)
" no "globbing" (performed by /etc/glob in v1 shell)
interactive:
-1
" v0 cat.s seems to write error output on fd 8, *BUT* shell doesn't
" know what device is on stdout (passed by init, and init doesn't pass
" fd 8), and there isn't a "dup" call, nor does init appear to be an
" "indirect" device like /dev/tty, nor does init make an equivalent link!!
" Arguments for new processes are located at the end of memory.
" Location 17777 points to a word with the argument count (argc),
" followed by blocks of four words with (filename) arguments.
" Currently leave room for ONLY maxargs items.
maxargs=8
" v1 shell expects "-" as argument from init or login, will read
" filename passed as argument. *BUT* v0 init.s doesn't set up the
" argv at the top of memory, so the v0 shell may not have taken
" command line arguments!!!
lac d1
sys intrp " make shell uninterruptable
sys getuid
sma " <0?
jmp newline " no, a mundane
jmp newline " no
lac hash " yes: superuser
dac prompt " change prompt
newline:
lac d1; sys write; prompt; 1 " output prompt
jms rline " read line into ibuf
lac iipt
dac ipt
newcom:
dzm char " clear saved char
dzm infile " clear input redirect file name
dzm outfile " clear output redirect file name
lac iopt " reset output pointer
lac iopt " reset output buffer pointer
dac opt
dac nextarg
" reset high memory
dzm argc " clear arg count
lac argcptr
lac argcptr " (re) set arg pointer
dac argptr
dzm argv0 " clear out argv0 for chdir comparison
dzm argv0+1
dzm argv0+2
" NOTE! behavior copied from v1 shell!!!
" "improvements" here may be non-historic!!
newarg:
-8 " save 8 chars
dac bcount
dzm redirect
dzm redirect " clear redirect flag
lac opt " save start for print (TEMP)
dac nextarg
jms blank " skip whitespace
jms delim " newline?
jms delim " command sep?
jmp eol " yes
sad lt " input redirect?
jmp redirin
@ -59,19 +79,18 @@ redirin: " saw <
dac redirect " flag redirect
lac infilep
dac opt
jmp newchar " v1 behavior? no whitespace eater
jmp newchar
redirout: " saw >
dac redirect " flag redirect
lac outfilep
dac opt
" v1 behavior? no whitespace eater!
" fall
newchar:
jms getc
sad o40 " space?
jmp ws " yes
jmp eoname " yes
jms delim
jmp eoname
3: jms putc " save
@ -81,22 +100,16 @@ newchar:
" here after 8 chars: discard until terminator seen
discard:
jms getc
dac char
sad o4
jmp eof
jms delim " end of line?
jmp eoname
sad o40
jmp eoname
jmp discard
" here with EOF in command: process command?
eof:
sys exit " quit, for now?
" name ended (short) with whitespace or newline
" name ended (short) with whitespace or delim
" pad out last name to 8 with spaces
ws:
" XXX check if ANYTHING read
eoname:
dac char " save terminator
1: lac o40
jms putc " no: copy into argv
@ -104,9 +117,7 @@ ws:
jmp 1b
" saw end of name
eoname:
dac char
lac redirect
2: lac redirect
sza
jmp 2f " last name was a redirect file, skip increment
@ -126,10 +137,10 @@ eoname:
jms delim
jmp eol
-maxargs
tad argc
sza
jmp newarg
lac argc
sad maxargwords
skp
jmp newarg
" too many args, (complain?). for now eat rest of line
4: jms getc
@ -160,69 +171,66 @@ eol:
jmp changedir
1:
" comment these out to test "exec"
" comment these out to test "exec" w/o fork
sys fork
jmp parent
" here in child
lac d2; sys close " close fd 2
sys unlink; exectemp " remove temp file
sys open; argv0; 0 " try cwd (no link required)
sma
jmp 1f
jmp cmderr
" try to link binary from "system" directory to "exectemp" file
" sys unlink; exectemp " remove old temp file, if any
" sys link; system; argv0; exectemp
" spa
" jmp notsys
" jmp cmderr
" sys open; exectemp; 0
" spa
" jmp error
" jmp cmderr
" dac cmdfd
" sys unlink; exectemp
" jmp 1f
"notsys: " not found in "system"
sys open; argv0; 0 " try cwd
spa
jmp cmderr
" skp
1: dac cmdfd " save command file descriptor
cla " check for input redirection
sad infile
jmp 1f
sad infile " input redirct?
jmp 1f " no
sys close " close fd 0
sys open; infile; 0 " open redirected
spa sna
jmp inerror
jmp inerror
cla
1: sad outfile
jmp exec
1: sad outfile " output redirec?
jmp exec " no
lac d1; sys close " close fd 1
lac o17
sys creat; outfile " open output redirect
lac o17; sys creat; outfile " open output redirect
spa
jmp outerror
jmp outerror
" here to "exec" file open on fd 2, adapted from init.s
" here to "exec" file open on cmdfd, adapted from init.s
exec:
law boot-1 " Get source addr
dac 8 " set up index 8 (pre-increments)
dac 8 " set up index (pre-increments)
law bootloc-1 " Copy "boot" code into high memory
dac 9 " set up index 9 (pre-increments)
dac 9 " set up index
-bootlen " isz loop count for bootstrap copy
dac bootcount
1: lac 8 i
dac 9 i
isz bootcount " can only do this once!
jmp 1b
lac cmdfd " get fd for the executable
lmq " Save the fd into MQ
jmp bootloc " and then jump to the code
" copied up to bootloc in high memory (below argc)
boot:
lac d2 " Load fd 2 (the opened executable)
lmq " Save the fd into MQ
sys read; userbase; userlen " read executable in
lacq " Get the fd back and close the file
sys close
sys close " close command file
jmp userbase " and jump to the beginning of the executable
bootlen=.-boot " length of bootstrap
bootcount: -bootlen " isz loop count for bootstrap copy
" error in child process:
inerror: " error opening input redirection
lac infilep
@ -236,7 +244,7 @@ error: " error in child: filename pointer in AC
dac 1f " save filename to complain about
lac d1; sys write; 1: 0; 4
lac d1; sys write; qmnl; 1
lac d2; sys close
lac d2; sys close " close executable, if any
sys exit
" chdir command: executed in shell process
@ -306,46 +314,48 @@ delim: 0
isz delim " ran the gauntlet: skip home
jmp delim i
" from cat.s
" get character from ibuf
getc: 0
lac ipt " Load pointer to next word in the buffer
sad eipt
jmp 1f " end of the buffer, so read more
dac 2f " Save the pointer
add o400000 " flip MSB, increment pointer on overflow
dac ipt
ral " Move the msb into the link register
lac 2f i " Load the word from the buffer
szl " Skip if second character in word
lrss 9 " first char: shift down the top character
and o177 " Keep the lowest 7 bits
sna
jmp getc+1 " Skip a NUL characters and read another one
jmp getc i " Return the character from the subroutine
lac ipt i " fetch char
isz ipt " increment pointer
jmp getc i
" from init.s rline: read line from tty into ibuf
" (store one character per word)
rline: 0
law ibuf-1 " Store ibuf pointer in location 8
dac 8
1:
cla " Buffer is empty, read another 64 characters
sys read; ibuf; 64
sna
jmp 1f " No characters were read in
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 getc+1 " and loop back to get one character
1:
lac o4 " No character, return with ctrl-D
jmp getc i " return from subroutine
cla; sys read; char; 1 " Read in one character from stdin
sna " read ok?
sys exit " EOF: quit
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
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
dac 8
jmp 1b " and loop back
putc: 0
and o177 " Keep the lowest 7 bits and save into 2f+1
dac 2f+1
lac opt " Save the pointer to the empty buffer
dac 2f " position to 2f
add o400000 " Flip the msb and save back into opt
dac opt " This also has the effect of incrementing
" the opt pointer every second addition!
lac opt " get output buffer pos
dac 2f " save
add o400000 " Flip the msb (advance) and save back into opt
dac opt
spa " If the bit was set, we already have one
jmp 1f " character at 2f+1. If no previous character,
lac 2f i " merge the old and new character together
@ -358,11 +368,7 @@ putc: 0
dac 2f i " Save the word into the buffer
jmp putc i " No, so return (more room still in the buffer)
2: 0;0 " Current input and output word pointers
ipt: 0 " Current input buffer base
eipt: 0 " Pointer to end of data read in input buffer
iipt: ibuf
ibuf: .=.+64
2: 0;0 " pointer, char
" literals
d1: 1
@ -371,10 +377,12 @@ o4:d4: 4
o12: 012 " newline
o17: 017
o40: 040 " space
o43: 043 " #
o46: 046 " ampersand
o73: 046 " semi
o74:lt: 074 " <
o76:gt: 076 " >
o100: 0100 " @
o177: 0177 " 7-bit (ASCII) mask
o400000: 0400000 " MSB
@ -396,29 +404,34 @@ star: <*> "
toomany: <to>;<o> ;<ma>;<ny>;< a>;<rg>;<s 012
ltoomany=.-toomany
" ################ variables
prompt: <@> " v1 prompt
pid: 0 " "other" pid
char: 0 " white space char
redirect: 0 " last file was a redirect (lt or gt)
bcount: 0 " byte counter for current filename
delimchar: 0 " character that terminated line
iopt:argv0p: argv0 " initial value for nextarg, opt
nextarg: 0 " next slot in argv to fill
opt: 0 " "output pointer" (may point to in/outfile)
maxargwords: maxargs+maxargs+maxargs+maxargs
argcptr: argc
infilep: infile
outfilep: outfile
iipt: ibuf
iopt:argv0p: argv0 " initial value for nextarg, opt
" ################ variables
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)
delimchar: .=.+1 " character that terminated line
char: .=.+1 " char that terminated word
outfile: .=.+4 " buffer for output redirect file name
infile: .=.+4 " buffer for input redirect file name
pid: .=.+1 " "other" pid
cmdfd: .=.+1 " fd for executable
bootcount: .=.+1 " loop count for "boot" copy
argcptr: argc
" leave room for maxargs items of 4 words each
maxargs=8
ipt: .=.+1 " input buf pointer
ibuf: " input line stored here, one character per word
userbase=010000 " user starts at 4K
argptr=017777 " last word points to argc + argv data
@ -431,4 +444,3 @@ argv0=argc+1
bootloc=argc-bootlen " location of bootstrap
userlen=bootloc-userbase " max executable

434
src/other/sh.s
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@ -1,434 +0,0 @@
" -*-fundamental-*-
" sh -- a shell
" started by p budne 3/4/2016
" with code from cat.s, init.s, and looking at the v1 (pdp-11) shell
" XXX cat.s seems to write error output on fd 8
start:
" XXX take command line argument (script file to open), suppress prompt??
" NOTE!!! v0 init.s doesn't set up the argv at the top of memory,
" so the v0 shell may not have taken command line arguments!!!
" if non-interactive, "dzm prompt", jump to newcom
interactive:
-1
sys intrp " make shell uninterruptable
sys getuid
sma " <0?
jmp newline " no, a mundane
lac hash " yes: superuser
dac prompt " change prompt
newline:
lac d1; sys write; prompt; 1 " output prompt
newcom:
dzm char " clear saved char
dzm infile " clear input redirect file name
dzm outfile " clear output redirect file name
lac iopt " reset output pointer
dac opt
dac nextarg
" reset high memory
dzm argc " clear arg count
lac argcptr
dac argptr
dzm argv0 " clear out argv0 for chdir comparison
dzm argv0+1
dzm argv0+2
newarg:
-8 " save 8 chars
dac bcount
dzm redirect
lac opt " save start for print (TEMP)
dac nextarg
jms blank " skip whitespace
jms delim " newline?
jmp eol " yes
sad lt " input redirect?
jmp redirin
sad gt " output redirect?
jmp redirout
jmp 3f
redirin: " saw <
dac redirect " flag redirect
lac infilep
dac opt
jmp newchar " v1 behavior? no whitespace eater
redirout: " saw >
dac redirect " flag redirect
lac outfilep
dac opt
" v1 behavior? no whitespace eater!
" fall
newchar:
jms getc
sad o40 " space?
jmp ws " yes
jms delim
jmp eoname
3: jms putc " save
isz bcount " loop unless full
jmp newchar
" here after 8 chars: discard until terminator seen
discard:
jms getc
dac char
sad o4
jmp eof
jms delim " end of line?
jmp eoname
sad o40
jmp eoname
jmp discard
" here with EOF in command: process command?
eof:
sys exit " quit, for now?
" name ended (short) with whitespace or newline
" pad out last name to 8 with spaces
ws:
dac char " save terminator
1: lac o40
jms putc " no: copy into argv
isz bcount " loop until full
jmp 1b
" saw end of name
eoname:
dac char
lac redirect
sza
jmp 2f " last name was a redirect file, skip increment
lac argc " increment argc
tad d4
dac argc
lac nextarg
tad d4 " advance nextarg
dac nextarg
2:
dzm redirect " clear redirect flag
lac nextarg
dac opt
lac char
jms delim
jmp eol
-maxargs
tad argc
sza
jmp newarg
" too many args, (complain?). for now eat rest of line
4: jms getc
jms delim
skp
jmp 4b
lac d1; sys write; toomany; ltoomany
jmp newline
" here at end of line
eol:
sad delimchar " save eol character
lac argc " check for empty command line
sna " get anything?
jmp 2f " no, go back for another
" check for built-in "chdir" command
lac argv0
sad chdirstr
skp
jmp 1f
lac argv0+1
sad chdirstr+1
skp
jmp 1f
lac argv0+2
sad chdirstr+2
jmp changedir
1:
" comment these out to test "exec"
sys fork
jmp parent
" here in child
lac d2; sys close " close fd 2
sys unlink; exectemp " remove temp file
" try to link binary from "system" directory to "exectemp" file
" sys link; system; argv0; exectemp
" spa
" jmp notsys
" sys open; exectemp; 0
" spa
" jmp error
" sys unlink; exectemp
" jmp 1f
"notsys: " not found in "system"
sys open; argv0; 0 " try cwd
spa
jmp cmderr
cla " check for input redirection
sad infile
jmp 1f
sys close " close fd 0
sys open; infile; 0 " open redirected
spa sna
jmp inerror
cla
1: sad outfile
jmp exec
lac d1; sys close " close fd 1
lac o17
sys creat; outfile " open output redirect
spa
jmp outerror
" here to "exec" file open on fd 2, adapted from init.s
exec:
law boot-1 " Get source addr
dac 8 " set up index 8 (pre-increments)
law bootloc-1 " Copy "boot" code into high memory
dac 9 " set up index 9 (pre-increments)
1: lac 8 i
dac 9 i
isz bootcount " can only do this once!
jmp 1b
jmp bootloc " and then jump to the code
" copied up to bootloc in high memory (below argc)
boot:
lac d2 " Load fd 2 (the opened executable)
lmq " Save the fd into MQ
sys read; userbase; userlen " read executable in
lacq " Get the fd back and close the file
sys close
jmp userbase " and jump to the beginning of the executable
bootlen=.-boot " length of bootstrap
bootcount: -bootlen " isz loop count for bootstrap copy
" error in child process:
inerror: " error opening input redirection
lac infilep
jmp error
outerror: " error opening new stdout (stdout closed!)
lac outfilep
skp
cmderr: " error opening command
lac argv0p
error: " error in child: filename pointer in AC
dac 1f " save filename to complain about
lac d1; sys write; 1: 0; 4
lac d1; sys write; qmnl; 1
lac d2; sys close
sys exit
" chdir command: executed in shell process
changedir:
" XXX check if argc == 4 (no directories) and complain??
lac argv0p
skp
1: lac 0f " increment argvp
tad d4
sad 0f
-4 " decrement argc
tad argc
dac argc
sna " done?
jmp 2f " 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
" here in parent, child pid in AC
parent:
" https://www.bell-labs.com/usr/dmr/www/hist.html
" The message facility was used as follows: the parent shell, after
" creating a process to execute a command, sent a message to the new
" process by smes; when the command terminated (assuming it did not
" try to read any messages) the shell's blocked smes call returned an
" error indication that the target process did not exist. Thus the
" shell's smes became, in effect, the equivalent of wait.
dac pid
lac delimchar
sad o46 " ampersand?
jmp newcom " yes: go back without wait
lac pid
sys smes " hang until child exits
2: lac delimchar
sad o73 " semi?
jmp newcom " yes: look for another command w/o prompt
jmp newline " no: output prompt
" ================
" subroutines
" eat spaces
" v1 routine name:
blank: 0
1: jms getc
sad o40
jmp 1b
jmp blank i
" give skip return if AC *NOT* a command delimiter
" v1 routine name:
delim: 0
sad o12 " newline
jmp delim i
sad o46 " ampersand
jmp delim i
sad o73 " semi
jmp delim i
isz delim " ran the gauntlet: skip home
jmp delim i
" from cat.s
getc: 0
lac ipt " Load pointer to next word in the buffer
sad eipt
jmp 1f " end of the buffer, so read more
dac 2f " Save the pointer
add o400000 " flip MSB, increment pointer on overflow
dac ipt
ral " Move the msb into the link register
lac 2f i " Load the word from the buffer
szl " Skip if second character in word
lrss 9 " first char: shift down the top character
and o177 " Keep the lowest 7 bits
sna
jmp getc+1 " Skip a NUL characters and read another one
jmp getc i " Return the character from the subroutine
1:
cla " Buffer is empty, read another 64 characters
sys read; ibuf; 64
sna
jmp 1f " No characters were read in
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 getc+1 " and loop back to get one character
1:
lac o4 " No character, return with ctrl-D
jmp getc i " return from subroutine
putc: 0
and o177 " Keep the lowest 7 bits and save into 2f+1
dac 2f+1
lac opt " Save the pointer to the empty buffer
dac 2f " position to 2f
add o400000 " Flip the msb and save back into opt
dac opt " This also has the effect of incrementing
" the opt pointer every second addition!
spa " If the bit was set, we already have one
jmp 1f " character at 2f+1. If no previous character,
lac 2f i " merge the old and new character together
xor 2f+1
jmp 3f " and go to the "save it in buffer" code
1:
lac 2f+1 " Move the character up into the top half
alss 9
3:
dac 2f i " Save the word into the buffer
jmp putc i " No, so return (more room still in the buffer)
2: 0;0 " Current input and output word pointers
ipt: 0 " Current input buffer base
eipt: 0 " Pointer to end of data read in input buffer
iipt: ibuf
ibuf: .=.+64
" literals
d1: 1
d2: 2
o4:d4: 4
o12: 012 " newline
o17: 017
o40: 040 " space
o46: 046 " ampersand
o73: 046 " semi
o74:lt: 074 " <
o76:gt: 076 " >
o177: 0177 " 7-bit (ASCII) mask
o400000: 0400000 " MSB
hash: <#> " superuser prompt
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
" TEMP FOR DEBUG:
star: <*> "
toomany: <to>;<o> ;<ma>;<ny>;< a>;<rg>;<s 012
ltoomany=.-toomany
" ################ variables
prompt: <@> " v1 prompt
pid: 0 " "other" pid
char: 0 " white space char
redirect: 0 " last file was a redirect (lt or gt)
bcount: 0 " byte counter for current filename
delimchar: 0 " character that terminated line
iopt:argv0p: argv0 " initial value for nextarg, opt
nextarg: 0 " next slot in argv to fill
opt: 0 " "output pointer" (may point to in/outfile)
infilep: infile
outfilep: outfile
outfile: .=.+4 " buffer for output redirect file name
infile: .=.+4 " buffer for input redirect file name
argcptr: argc
" leave room for maxargs items of 4 words each
maxargs=8
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

10
src/sys/s3.s
View File

@ -356,12 +356,12 @@ wppto:
jms swap
jmp wppto
" common exit for special file
" common exit for special file input
passone:
sad o4000
jmp okexit
dac u.base i
lac d1
sad o4000 " CTRL/D?
jmp okexit " yes: return zero
dac u.base i " no: save for user
lac d1 " return 1
dac u.ac
jmp sysexit

2
src/sys/s7.s
View File

@ -114,7 +114,7 @@ dsprestart:
isz ttydelay
krb " read keyboard buffer
dac char " save in char
sad o375 " interrupt char ('}'?)
sad o375 " interrupt char (TTY ALT MODE?)
jmp intrp1 " yes
lac d1
jms putchar

2
tools/3dump
View File

@ -14,7 +14,7 @@ while (1) {
my $result= read($IN, my $three, 3);
last if ($result != 3); # Not enough bytes read
my ($b1, $b2, $b3)= unpack("CCC", $three);
my $word= (($b1 & 077) << 12) | ($b2 << 6) | $b3;
my $word= (($b1 & 077) << 12) | (($b2 & 077) << 6) | ($b3 & 077);
my $c1= ($word >> 9) & 0777;
$c1= ($c1 < 0200) ? chr($c1) : " ";

74
tools/a7out
View File

@ -81,6 +81,18 @@ sub load_code {
# Open up the PDP-7 executable file
open( my $IN, "<", $filename ) || die("Unable to open $filename: $!\n");
my $c = getc($IN);
seek $IN, 0, 0;
if ((ord($c) & 0300) == 0200) { # handle "binary paper tape" format
my $addr = 010000; # user programs loaded at 4K mark
while ($addr <= 017777) {
my $result = read_word($IN);
last if ($result == -1);
$Mem[$addr++] = $result;
}
close($IN);
return;
}
while (<$IN>) {
chomp;
@ -98,6 +110,18 @@ sub load_code {
close($IN);
}
### read a word from a file in paper tape binary format
### return -1 on EOF
sub read_word {
my $F = shift;
# Convert three bytes into one 18-bit word
return -1 if ( read( $F, my $three, 3 ) != 3 ); # Not enough bytes read
my ( $b1, $b2, $b3 ) = unpack( "CCC", $three );
return ((($b1 & 077) << 12 ) |
(($b2 & 077) << 6 ) |
($b3 & 077));
}
### Copy the arguments into the PDP-7 memory space, and build
### an array of pointers to these arguments. Build a pointer
### at MAXADDR that points at the array.
@ -711,16 +735,19 @@ sub sys_fork {
return;
}
# Smes system call. Because we fake rmes with wait(),
# there is no need for sms. When the child does
# sys exit, that's going to wake wait() up and do the
# rmes anyway.
# shell depends on smes hanging while child process exists
# https://www.bell-labs.com/usr/dmr/www/hist.html
# The message facility was used as follows: the parent shell, after
# creating a process to execute a command, sent a message to the new
# process by smes; when the command terminated (assuming it did not
# try to read any messages) the shell's blocked smes call returned an
# error indication that the target process did not exist. Thus the
# shell's smes became, in effect, the equivalent of wait.
sub sys_smes {
# For now, do nothing
dprintf("smes system call\n");
waitpid($AC,0);
dprintf("smes returning error\n");
$AC = -1;
$PC += 1;
return;
}
# Rmes system call. We simply call wait and
@ -927,34 +954,35 @@ sub sys_read {
# Read each word in
my $FH = $FD[$fd];
$count = 0;
my $tty = -t $FH;
if (-t $FH) { # TTY?
my $char = getc($FH); # use Term::ReadKey for 'cbreak' mode??
if (defined($char)) {
$Mem[$start] = ord($char) << 9; # only ever returns one char
$AC = 1;
}
else {
$AC = 0; # EOF
}
return;
}
foreach my $addr ( $start .. $end ) {
if ( $ISBINARY[$fd] ) {
# Convert three bytes into one 18-bit word
my $result = read( $FH, my $three, 3 );
last if ( $result != 3 ); # Not enough bytes read
my ( $b1, $b2, $b3 ) = unpack( "CCC", $three );
$Mem[$addr] = ((($b1 & 077) << 12 ) |
(($b2 & 077) << 6 ) |
($b3 & 077));
my $result = read_word($FH);
last if ($result == -1);
$Mem[$addr] = $result;
$count++;
}
else {
# Convert two ASCII characters into one 18-bit word
my $c1 = getc($FH);
my $c2;
last if ( !defined($c1) ); # No character, leave the loop
my $word = ord($c1) << 9;
if ( !$tty || $c1 ne "\n") {
$c2 = getc($FH);
if (defined($c2)) {
$word |= ord($c2);
}
}
my $c2 = getc($FH);
$word |= ord($c2) if (defined($c2));
$Mem[$addr] = $word;
$count++;
last if ($tty && (($c1 && ($c1 eq "\n")) || ($c2 &&($c2 eq "\n"))));
} # ascii
}