gno/bin/gsh/invoke.asm
tribby e586eeefeb Changes for gsh version 2.0d9:
Added additional optional debug code. A version of gsh with the memory
checking debug code turned on is available as an exe file.

Lock and unlock the hash mutual exclusion key in when disposing of the
hash table.

Allow five digits rather than four when printing the process number in
the ps command.

Piping the output of a command into a non-executable file no longer
causes gsh to hang.
1999-01-14 17:44:25 +00:00

867 lines
16 KiB
NASM

*************************************************************************
*
* The GNO Shell Project
*
* Developed by:
* Jawaid Bazyar
* Tim Meekins
*
* $Id: invoke.asm,v 1.11 1999/01/14 17:44:25 tribby Exp $
*
**************************************************************************
*
* INVOKE.ASM
* By Tim Meekins
* Modified by Dave Tribby for GNO 2.0.6
*
* Command invocation routines.
*
* Note: text set up for tabs at col 16, 22, 41, 49, 57, 65
* | | | | | |
* ^ ^ ^ ^ ^ ^
**************************************************************************
*
* Interfaces defined in this file:
*
* redirect subroutine (4:sfile,4:dfile,4:efile,2:app,2:eapp,2:pipein,
* 2:pipeout,2:pipein2,2:pipeout2)
* returns with carry set/clear to indicate failure/success
*
* invoke subroutine (2:argc,4:argv,4:sfile,4:dfile,4:efile,2:app,
* 2:eapp,2:bg,4:cline,2:jobflag,2:pipein,2:pipeout,
* 2:pipein2,2:pipeout2,4:pipesem,4:awaitstatus)
* return 2:rtnval
*
**************************************************************************
mcopy /obj/gno/bin/gsh/invoke.mac
dummyinvoke start ; ends up in .root
end
setcom 60
SIGINT gequ 2
SIGKILL gequ 9
SIGTERM gequ 15
SIGSTOP gequ 17
SIGTSTP gequ 18
SIGCONT gequ 19
SIGCHLD gequ 20
SIGTTIN gequ 21
SIGTTOU gequ 22
**************************************************************************
*
* Redirect
*
**************************************************************************
redirect START
space equ 1
pipeout2 equ space+3
pipein2 equ pipeout2+2
pipeout equ pipein2+2
pipein equ pipeout+2
eapp equ pipein+2
app equ eapp+2
efile equ app+2
dfile equ efile+4
sfile equ dfile+4
end equ sfile+4
; subroutine (4:sfile,4:dfile,4:efile,2:app,2:eapp,2:pipein,2:pipeout,2:pipein2,2:pipeout2),space
* NOTE: only called from invoke, after fork_mutex is locked
tsc
phd
tcd
;
; Redirect standard input
;
ora2 sfile,sfile+2,@a If no name provided,
beq execa skip it.
pei (sfile+2) Convert c-string
pei (sfile) filename to
jsr c2gsstr GS/OS string.
sta RedirectFile Store filename pointer
stx RedirectFile+2 in parameter block.
stz RedirectDev stdin devnum = 0.
stz RedirectApp Cannot append.
RedirectGS RedirectParm
php
ph4 RedirectFile Free allocated GS/OS string.
jsl nullfree
plp
bcc execa If RedirectGS failed,
ldx #^err1 print error message:
lda #err1 'Error redirecting standard input.'
jmp badbye and quit.
;
; Redirect standard output
;
execa ora2 dfile,dfile+2,@a
beq execb
pei (dfile+2)
pei (dfile)
jsr c2gsstr
sta RedirectFile
stx RedirectFile+2
ld2 1,RedirectDev stdout devnum = 1
mv2 app,RedirectApp
RedirectGS RedirectParm
php
ph4 RedirectFile
jsl nullfree
plp
bcc execb
ldx #^err2 Print error message:
lda #err2 'Error redirecting standard output.'
jmp badbye
;
; Redirect standard error
;
execb ora2 efile,efile+2,@a
beq execc
pei (efile+2)
pei (efile)
jsr c2gsstr
sta RedirectFile
stx RedirectFile+2
ld2 2,RedirectDev
mv2 eapp,RedirectApp
RedirectGS RedirectParm
php
ph4 RedirectFile
jsl nullfree
plp
bcc execc
ldx #^err3 Print error message:
lda #err3 'Error redirecting standard error.'
jmp badbye
;
; Is input piped in?
;
execc lda pipein
beq execd
dup2 (pipein,#1)
mv2 pipein2,CloseRef
Close CloseParm
ldx #0
lda pipein
SetInputDevice (#3,@xa)
;
; Is output piped?
;
execd lda pipeout
beq exece
dup2 (pipeout,#2)
mv2 pipeout2,CloseRef
Close CloseParm
ldx #0
lda pipeout
SetOutputDevice (#3,@xa)
exece anop
;
; All the file and pipe redirection has been handled. Time to say goodbye.
;
goodbye ldy #0
bra exit
badbye jsr errputs
cop $7F ; get out of the way
ldy #1
exit lda space
sta end-3
lda space+1
sta end-2
pld
tsc
clc
adc #end-4
tcs
cpy #1 Clear/set carry for success/failure.
rtl
;
; Parameter block for shell call to redirect I/O (ORCA/M manual p.425)
;
RedirectParm dc i2'3' pCount
RedirectDev ds 2 Dev num (0=stdin,1=stdout,2=errout)
RedirectApp ds 2 Append flag (0=delete)
RedirectFile ds 4 File name (GS/OS input string)
;
; Parameter block for GS/OS call to close a file
;
CloseParm dc i'1' pCount
CloseRef dc i'0' refNum
err1 dc c'gsh: Error redirecting standard input.',h'0d00'
err2 dc c'gsh: Error redirecting standard output.',h'0d00'
err3 dc c'gsh: Error redirecting standard error.',h'0d00'
END
**************************************************************************
*
* Invoke a command (PHASE 0)
*
**************************************************************************
invoke START
using hashdata
using vardata
using global
using pdata
p equ 0
biflag equ p+4
ptr equ biflag+2
rtnval equ ptr+4 Return pid, -1 (error), or 0 (no fork)
cpath equ rtnval+2
hpath equ cpath+4
space equ hpath+4
subroutine (2:argc,4:argv,4:sfile,4:dfile,4:efile,2:app,2:eapp,2:bg,4:cline,2:jobflag,2:pipein,2:pipeout,2:pipein2,2:pipeout2,4:pipesem,4:awaitstatus),space
ld2 -1,rtnval
stz biflag Clear built-in flag
stz hpath and address from hash table.
stz hpath+2
lda argc If number of arguments == 0,
bne chknull nothing to do. (Shouldn't happen
nulldone jmp done because invoke checks argc==0).
;
; Check for null command
;
chknull ldy #2 Move 1st argument
lda [argv] pointer to
sta cpath cpath (4 bytes).
lda [argv],y
sta cpath+2 If pointer == NULL
ora cpath
beq nulldone all done.
lda [cpath] If first character == '\0',
and #$FF
beq nulldone all done.
;
; Check command: is it builtin, in hash table, etc?
;
pei (cpath+2) IsBuiltin returns
pei (cpath) 0 if forked built-in
jsl IsBuiltin 1 if non-forked built-in
cmp #-1 -1 if not a built-in
jne trybuiltin
;
; Command is not listed in the built-in table. See if it was hashed
;
pei (cpath+2)
pei (cpath)
ph4 hash_table
ph4 #hash_paths
jsl search
cmp #0
bne changeit
cpx #0
beq noentry
changeit sta cpath Use full path from
stx cpath+2 hash table.
sta hpath Save adddress for deallocation.
stx hpath+2
;
; Get information about the command's filename
;
noentry lock info_mutex
pei (cpath+2)
pei (cpath)
jsr c2gsstr
sta GRecPath
sta ptr
stx GRecPath+2
stx ptr+2
GetFileInfo GRec
unlock info_mutex
jcs notfound If error getting info, print error.
; Is file type $B5: GS/OS Shell application (EXE)?
if2 GRecFileType,eq,#$B5,doExec
; Is file type $B3: GS/OS application (S16)?
if2 @a,eq,#$B3,doExec
ldx vardirexec If $NODIREXEC isn't set, and
bne ft02
cmp #$0F
jeq doDir file is a directory: change to it.
; Is file type $B0: source code file (SRC)?
ft02 if2 @a,ne,#$B0,badfile
; Type $B0, Aux $00000006 is a shell command file (EXEC)
if2 GRecAuxType,ne,#6,badfile
if2 GRecAuxType+2,ne,#0,badfile
jmp doShell
;
; Command file is not an appropriate type
;
badfile ldx cpath+2
lda cpath
jsr errputs
ldx #^err1 Print error message:
lda #err1 'Not executable.'
jsr errputs
pei (ptr+2) Free memory used to hold
pei (ptr) GS/OS string with path.
jsl nullfree
jmp chkpipe If pipe was allocated, clean up.
*
* ---------------------------------------------------------------
*
* Launch an executable (EXE or S16 file)
doExec pei (ptr+2)
pei (ptr)
jsl nullfree
jsr prefork
fork #invoke0
jsr postfork
jmp done
;
; Forked shell starts here...
;
invoke0 phk Make sure data bank register
plb is the same as program bank.
;
; Make copies of command line (cline) and path (cpath) for child
;
pha
pha
tsc
phd
tcd
ldx #0
tsc
FindHandle @xa,1
ldy #6
lda [1],y ;This is the UserID!
and #$F0FF
pha
ph4 _cline
jsr cstrlen
inc a
ply
pha
ldx #0
NewHandle (@xa,@y,#$4018,#0),1
ply
ldx #0
PtrToHand (_cline,1,@xy)
ldy #2
lda [1],y
tax
lda [1]
pld
ply
ply
phx ;_cline
pha
;
pha
pha
tsc
phd
tcd
ldx #0
tsc
FindHandle @xa,1
ldy #6
lda [1],y ;This is the UserID!
and #$F0FF
pha
ph4 _cpath
jsr cstrlen
inc a
ply
pha
ldx #0
NewHandle (@xa,@y,#$4018,#0),1
ply
ldx #0
PtrToHand (_cpath,1,@xy)
ldy #2
lda [1],y
tax
lda [1]
pld
ply
ply
phx ;_cpath
pha
jsl infork
bcs invoke1
;
; Call _execve(_cpath,_cline) to replace forked shell with executable file
;
case on
jsl _execve For 2.0.6: call _execve, not execve
case off
rtl
;
; Error reported by infork; clean up stack and return to caller
;
invoke1 pla
pla
pla
pla
rtl
*
* ---------------------------------------------------------------
*
* Next command is a directory name, so change to that directory
doDir lock cdmutex
mv4 GRecPath,PRecPath
SetPrefix PRec
unlock cdmutex
pei (ptr+2) Free memory used to hold
pei (ptr) GS/OS string with path.
jsl nullfree
lda #0 Completion status = 0.
;
; Rest of cleanup is shared with non-forked builtin
;
jmp nfcleanup
*
* ---------------------------------------------------------------
*
* Next command is a shell command file: fork a shell script
doShell anop
inc biflag ;don't free argv...
jsr prefork
* int fork2(void *subr, int stack, int prio, char *name, word argc, ...)
pea 0
ldy #2
lda [argv],y
pha
lda [argv]
pha
pea 0
pea 1024
ph4 #exec0
case on
jsl fork2
case off
jsr postfork
pei (ptr+2) Free memory used to hold
pei (ptr) GS/OS string with path.
jsl nullfree
jmp done
;
; Forked shell starts here...
;
exec0 anop
ph4 _hpath argfree parameters.
ph2 _argc
ph4 _argv
ph4 _cpath ShellExec parameters
ph2 _argc
ph4 _argv
jsl infork
bcs exec0c
signal (#SIGCHLD,#0)
PushVariablesGS NullPB
pea 1 jobflag = 1
jsl ShellExec
jsl argfree
PopVariablesGS NullPB
rtl
;
; Error reported by infork; clean up stack and return to caller
;
exec0c pla
pla
pla
pla
pla
pla
pla
pla
rtl
; Null parameter block used for shell calls PushVariables
; (ORCA/M manual p.420) and PopVariablesGS (p. 419)
NullPB dc i2'0' pCount
*
* ---------------------------------------------------------------
*
* File name was found in the built-in table
trybuiltin inc biflag It's a built-in. Which type?
cmp #1 Either fork or don't fork.
beq noforkbuiltin
;
; It's a forked builtin
;
jsr prefork
fork #forkbuiltin
jsr postfork
jmp done
;
; Control transfers here for a forked built-in command
;
forkbuiltin anop
cop $7F Give palloc a chance
ph2 _argc
ph4 _argv
jsl infork
bcs fork0c
jsl builtin
rtl
;
; Error reported by infork; clean up stack and return to caller
;
fork0c pla
pla
pla
rtl
* ---------------------------------------------------------------
;
; It's a non-forked builtin
;
noforkbuiltin anop
pei (argc)
pei (argv+2)
pei (argv)
jsl builtin
and #$00FF Make return status look like result of
xba wait(): high-order byte = status.
nfcleanup anop
sta [awaitstatus]
stz rtnval Return value (pid) = no fork done.
;
; There might be a process waiting on a pipe
;
lda [pipesem]
sta _semaphore
bra chkpipe
*
* ---------------------------------------------------------------
*
* Command was not found as built-in or as a file
notfound pei (ptr+2)
pei (ptr)
jsl nullfree
ldy #2
lda [argv],y
tax
lda [argv]
jsr errputs
ldx #^err2 Print error message:
lda #err2 'Command not found.'
jsr errputs
chkpipe lda pipein
beq done
; Input being piped into a command that was not found.
ssignal _semaphore
sdelete _semaphore
mv4 pjoblist,p
ldy #16 ;p_jobid
lda [p],y Get forked process's pid.
_getpgrp @a Get forked process's group number.
eor #$FFFF
inc a
kill (@a,#9) Kill all processes in that group.
sigpause #0
done cop $7F
lda biflag If built-in flag is clear,
bne skipfrarg
pei (hpath+2) Free arguments.
pei (hpath)
pei (argc)
pei (argv+2)
pei (argv)
jsl argfree
skipfrarg pei (cline+2) Free command-line.
pei (cline)
jsl nullfree
return 2:rtnval
* ---------------------------------------------------------------
*
* Support routines
*
* ---------------------------------------------------------------
;
; Tasks to do just before forking
;
prefork lock fork_mutex Lock the fork mutual exclusion.
SetInGlobals (#$FF,#00)
;
; Move essential parameters from stack to mutual-exclusion protected memory
;
mv4 sfile,_sfile
mv4 dfile,_dfile
mv4 efile,_efile
mv2 app,_app
mv2 eapp,_eapp
mv4 cline,_cline
mv4 cpath,_cpath
mv4 hpath,_hpath
mv2 argc,_argc
mv4 argv,_argv
mv2 pipein,_pipein
mv2 pipeout,_pipeout
mv2 pipein2,_pipein2
mv2 pipeout2,_pipeout2
mv2 bg,_bg
mv2 jobflag,_jobflag
lda [pipesem]
sta _semaphore
lda pipesem Set address of
sta putsem+1 semaphone in
lda pipesem+1 LDA instruction.
sta putsem+2
rts
* ---------------------------------------------------------------
;
; Tasks the parent process does right after forking
;
postfork sta rtnval Save pid as return value.
lda pipein If pipein != 0,
beq postfork2
sta CloseRef
Close CloseParm close pipein.
postfork2 lda pipeout If pipeout != 0,
beq postfork3
sta CloseRef
Close CloseParm close pipeout.
postfork3 lda rtnval If return value == -1,
cmp #-1
bne postfork4
ldx #^deadstr Print error message:
lda #deadstr 'Cannot fork (too many processes?)'
jsr errputs
unlock fork_mutex Unlock the fork mutual exclusion.
jmp postfork6 Return to caller.
postfork4 ldx jobflag
dex
beq postfork5 If jobflag == 1,
pha
pei (bg)
pei (cline+2)
pei (cline)
lda pipein if pipein == 0,
bne postfork4a
jsl palloc palloc(0,cline)
bra postfork5 else
postfork4a jsl pallocpipe pallocpipe(0,cline)
postfork5 anop
;
; Wait for fork mutual exclusion lock to clear (cleared by infork)
;
lda >fork_mutex ;DANGER!!!!! Assumes knowledge of
beq postfork6 ;lock/unlock structure!!!!!!!!
cop $7F
bra postfork5
postfork6 rts
* ---------------------------------------------------------------
;
; Startup tasks by forked process
;
infork phk Make sure data bank register
plb is the same as program bank.
;
; NOTE: next two lines were added for v2.0.6 in order to prevent background
; processes from being waited on when they are kicked off from an
; exec file. The side effect of having the process become owned by
; the null process may not be desired. (Perhaps there is a better way!)
;
lda _bg If in background
bne optty
lda _jobflag or jobflag == 0,
bne infork0b
optty Open ttyopen Open tty.
jcs errinfork
lda _pipein
bne infork0a If not in pipeline,
tcnewpgrp ttyref allocate new process group.
infork0a settpgrp ttyref Set current process to have proc group.
lda _bg If in background,
beq infork0b
tctpgrp (gshtty,gshpid) reset tty to the shell process group.
infork0b ph4 _sfile Redirect I/O
ph4 _dfile
ph4 _efile
ph2 _app
ph2 _eapp
ph2 _pipein
ph2 _pipeout
ph2 _pipein2
ph2 _pipeout2
jsl redirect
jcs errinfork
unlock fork_mutex
;
; Wait on appropriate pipe semaphores
;
lda _pipein
bne infork0c
lda _pipeout
beq clean_exit
;
; _pipein == 0 && _pipeout != 0
;
screate #0 Create a semaphore with count=0.
putsem sta >$FFFFFF Store semaphore number in pipesem.
swait @a Block on semaphore until ssignal.
bra clean_exit
infork0c lda _pipeout
bne clean_exit
;
; _pipein != 0 && _pipeout != 0
;
waitsemy lda _semaphore While _semaphore == 0,
bne goodsemy
cop $7F allow other processes to run.
bra waitsemy
goodsemy ssignal _semaphore Release _semaphore
sdelete _semaphore and delete it.
clean_exit anop
clc
bra indone
;
; Arrive at "errinfork" if ttyopen or redirect didn't work.
;
errinfork unlock fork_mutex
; sec Note: carry already set
indone rtl Return to caller; status in carry.
fork_mutex key Mutual exclusion for forking
info_mutex key Mutual exclusion for GetFileInfo
cdmutex key Mutual exclusion for SetPrefix
;
; Variables protected by fork_mutex (set by parent, used by child process)
;
_argc dc i2'0'
_argv dc i4'0'
_sfile dc i4'0'
_dfile dc i4'0'
_efile dc i4'0'
_app dc i2'0'
_eapp dc i2'0'
_cline dc i4'0'
_cpath dc i4'0'
_hpath dc i4'0'
_pipein dc i2'0'
_pipeout dc i2'0'
_pipein2 dc i2'0'
_pipeout2 dc i2'0'
_bg dc i2'0'
_jobflag dc i2'0'
_semaphore dc i2'0'
;
; String constants
;
str dc c'[0]',h'0d00'
err1 dc c': Not executable.',h'0d00'
err2 dc c': Command not found.',h'0d00'
deadstr dc c'Cannot fork (too many processes?)',h'0d00' ;try a spoon
; Parameter block for GS/OS call GetFileInfo
GRec dc i'4' pCount (# of parameters)
GRecPath ds 4 pathname (input; ptr to GS/OS string)
ds 2 access (access attributes)
GRecFileType ds 2 fileType (file type attribute)
GRecAuxType ds 4 auxType (auxiliary type attribute)
PRec dc i'2'
PRecNum dc i'0'
PRecPath ds 4
CloseParm dc i2'1'
CloseRef dc i2'0'
Err dc i2'0'
; Parameter block for opening tty
ttyopen dc i2'2'
ttyref dc i2'0'
dc i4'ttyname'
ttyname gsstr '.tty'
END