gno/bin/gsh/shell.asm
tribby 05d82736bc Changes for gsh version 2.0d10:
Add check for buffer overflow when globbing, expanding variables, or
inserting aliases (PR#110).  Increase buffer size from 1024 to 4096.

Increase buffer for reading commands from 256 to 1024 bytes in order
to match the maximum length used when reading.
1999-02-08 17:26:51 +00:00

639 lines
13 KiB
NASM

**************************************************************************
*
* The GNO Shell Project
*
* Developed by:
* Jawaid Bazyar
* Tim Meekins
*
* $Id: shell.asm,v 1.10 1999/02/08 17:26:51 tribby Exp $
*
**************************************************************************
*
* SHELL.ASM
* By Tim Meekins
* Modified by Dave Tribby for GNO 2.0.6
*
* This is the main routines for the shell.
*
* Note: text set up for tabs at col 16, 22, 41, 49, 57, 65
* | | | | | |
* ^ ^ ^ ^ ^ ^
**************************************************************************
*
* Interfaces defined in this file:
*
* shell subroutine (0:dummy)
* NOTE: gnoloop is an entry defined in shell.
*
* AppendHome subroutine (4:str)
* return 4:outPtr
*
* Dogshrc jsr with no parameters
*
* signal2 subroutine (4:fubar)
*
* signal18 subroutine (4:fubar)
*
**************************************************************************
mcopy /obj/gno/bin/gsh/shell.mac
dummyshell start ; ends up in .root
end
setcom 60
SIGINT gequ 2
SIGTSTP gequ 18
SIGCHLD gequ 20
cmdbuflen gequ 1024
**************************************************************************
*
* shell: entry point for acting upon commands
*
**************************************************************************
case on
shell start
case off
using global
using pdata
using HistoryData
using termdata
p equ 0 General pointer
cflag equ p+4 Flag: set when path converted
space equ cflag+2
subroutine (0:dummy),space
tsc Save stack pointer
sta cmdcontext in cmdcontext
tdc and direct page reg
sta cmddp in cmddp.
PushVariablesGS NullPB Save environment variables.
Open ttyopen Open tty,
bcc settty checking for error.
ErrWriteCString #ttyerr
jmp quit
ttyerr dc c'gsh: Failed opening tty.',h'0d00'
settty mv2 ttyref,gshtty
tcnewpgrp gshtty
settpgrp gshtty
getpid
sta gshpid
jsr InitTerm
lda FastFlag If FastFlag is set,
bne fastskip1 skip copyright message.
lda gshpid Only print the copyright msg
cmp #2 if not using login
bne fastskip1
ldx #^gnostr
lda #gnostr
jsr puts
fastskip1 anop
;
; Set up signal handlers
;
signal (#SIGINT,#signal2)
signal (#SIGTSTP,#signal18)
signal (#SIGCHLD,#pchild)
;
; Set entry point for users calling system
;
setsystemvector #system
;
; Initialize some stuff
;
jsr initalias Set all AliasTable entries to 0.
jsr InitDStack Zero out directory stack.
jsr InitVars Set value of all env var flags.
;
; Check for login shell (argv[0] starts with '-')
;
mv4 ~COMMANDLINE,p Copy commandline addr to dir page.
ldy #8 Skip over shell identifier
lda [p],y to get first char of
and #$FF command name.
cmp #'-' If not '-',
bne nologin_init skip over login initialization.
; Change ":" to " " in $PATH if it doesn't start with ":" or contain a " "
ph4 #pathname Get $PATH environment variable string
jsl getenv
sta p Save address of allocated buffer.
stx p+2 in direct page variable
ora p+2 If null,
beq nopathconv no need to convert
stz cflag Initialize conversion flag = false.
ldy #4 Index over GS/OS length fields.
short m Use 8-bit mode.
lda [p],y
beq endpathconv If null string, or
cmp #':' if first character is ':',
beq endpathconv don't do the conversion.
bumpit iny
lda [p],y
beq endpathconv If at end of string, all done.
cmp #' ' If $PATH contains a space,
bne chkcolon
stz cflag abort the conversion.
bra endpathconv
chkcolon cmp #':' If next character is ':',
bne bumpit
lda #' ' change it to ' ', and
sta [p],y
sta cflag set conversion flag = true.
bra bumpit
endpathconv long m Back to 16-bit mode.
lda cflag If there was no conversion,
beq freepath skip the setting of $PATH.
clc Address of $PATH as a GS/OS
lda p output string is 2 bytes
adc #2 beyond the input string
sta SetValue starting address.
lda p+2
adc #0
sta SetValue+2
SetGS SetPB Set $PATH to the converted value.
freepath ph4 p Free the $PATH C string.
jsl nullfree
nopathconv anop
; Read and execute /etc/glogin
ph4 #etcglogin path = "/etc/glogin"
lda #0
pha argc = 0
pha argv = NULL
pha
lda #$8000
pha jobflag = $8000
jsl ShellExec
; Read and execute $HOME/glogin
jsr Doglogin
;
; Initialization that is not specific to login shells
;
nologin_init anop
lda FastFlag If fast startup flag isn't set,
bne fastskip2
jsr InitHistory Init: historyFN->"$HOME/history",
jsr ReadHistory read in history from disk,
jsr Dogshrc and read $HOME/gshrc.
jsr newline
fastskip2 anop
lda didReadTerm
bne didit
jsr readterm
didit anop
jsr dispose_hash Remove old table (if set in
jsl hashpath login files) and hash $PATH.
ld2 1,done_init Set initialization done flag.
;
; Check for command-line arguments -c and -e
;
lda CmdFlag
beq cmdskip
;
; The -c flag is set: execute remaining arguments as a command file and exit.
;
mv4 CmdArgV,p
ldy #2
lda [p],y
pha
lda [p]
pha
ph2 CmdArgc argc
pei (p+2) argv
pei (p)
pea 0 jobflag = 0
jsl ShellExec
jmp done1
cmdskip lda ExecFlag
beq execskip
;
; The -e flag is set: execute remaining arguments as a command and exit.
;
ph4 ExecCmd cmdline
ph2 #0 jobflag = 0
jsl execute
jmp done1
;
; Parameter block for shell SetGS calls (p 427 in ORCA/M manual)
;
SetPB dc i2'3' pCount
dc i4'pathname' Name (pointer to GS/OS string)
SetValue ds 4 Value (pointer to GS/OS string)
dc i2'1' Export flag
pathname gsstr 'path' GS/OS string
etcglogin dc c'/etc/glogin',h'00'
execskip anop
****************************************************************
*
* Main loop for reading and executing commands
*
****************************************************************
stz lastabort
gnoloop entry
;
; Set the fundamental registers.
;
phk Copy Program Bank register
plb into Data Bank register.
lda cmdcontext Set Stack Pointer and
tcs Direct Page register
lda cmddp to values saved when
tcd entering shell.
jsl WritePrompt Print prompt.
jsr GetCmdLine Get response.
bcs done
jsr newline
lda cmdlen Check for empty string.
beq gnoloop
jsr cursoron
jsr newlineX
jsr flush
ph4 #cmdline execute(cmdline,0)
ph2 #0 jobflag = 0
jsl execute
lda exit_requested
bne done1
jsr newlineX
stz lastabort
bra gnoloop
;
; shut down gsh
;
done jsr newline
jsr newlineX
done1 ora2 pjoblist,pjoblist+2,@a
beq done2
lda lastabort
bne donekiller
inc lastabort
stz exit_requested
ldx #^stopstr Print message:
lda #stopstr "There are stopped jobs"
jsr puts
jsr newlineX
bra gnoloop Continue getting commands.
donekiller jsl jobkiller
done2 lda FastFlag
bne fastskip5
jsl SaveHistory
fastskip5 jsr dispose_hash
quit PopVariablesGS NullPB
Quit QuitParm
QuitParm dc i'0'
; Null parameter block used for shell calls PushVariables
; (ORCA/M manual p.420) and PopVariablesGS (p. 419)
NullPB dc i2'0' pCount
gnostr dc h'0d',c'GNO/Shell 2.0.6',h'0d'
dc c'Copyright 1991-1993, Procyon, Inc. & Tim Meekins. '
dc c'ALL RIGHTS RESERVED',h'0d'
dc h'0d00'
stopstr dc c'gsh: There are stopped jobs.',h'0d00'
ttyopen dc i2'2'
ttyref dc i2'0'
dc i4'ttyname'
ttyname gsstr '.tty'
exitstr dc c'000000',h'0d00'
lastabort ds 2
END
;=========================================================================
;
; Interpret the login file (gshrc).
; If $HOME is set, we presume the gshrc file is there. If not,
; or if an error occurs getting the $HOME variable, we use
; @:gshrc.
;
;=========================================================================
Dogshrc START
ph4 #gshrcName
bra doit
; Alternate entry point: execute $HOME/glogin
Doglogin ENTRY
ph4 #gloginName
doit jsl AppendHome
phx Save pointer to GS/OS input
pha string for later.
clc Adjust the pointer
adc #2 to skip the length word
bcc no_ovf so it's a C string.
inx
no_ovf phx
pha
* ShellExec subroutine (4:path,2:argc,4:argv,2:jobflag)
; (ptr to $HOME/gshrc is on stack)
lda #0
pha argc = 0
pha argv = NULL
pha
lda #$8000
pha jobflag = $8000
jsl ShellExec
; Dispose $HOME/gshrc string
pla Get address of
plx GS/OS input string.
sec Subtract two bytes to get
sbc #2 addr of original output buffer.
bcs no_undf
dex
no_undf phx
pha
jsl nullfree
rts
gshrcName dc c'/gshrc',h'00'
gloginName dc c'/glogin',h'00'
END
;=========================================================================
;
; Append a C string to the value of the $HOME variable. If $HOME is
; not set, then it appends the C string to the string '@/'. Returns
; a pointer to a GS/OS input string.
;
;=========================================================================
AppendHome START
outPtr equ 0 Pointer into allocated memory
str_len equ outPtr+4 Length of string parameter
buf_len equ str_len+2 Size of GS/OS buffer
space equ buf_len+2
subroutine (4:str),space
lock mutex
;
; Get the variable's length using ReadVariableGS
;
ld4 TempResultBuf,RVresult Use temporary result buf.
ReadVariableGS ReadVar Get length.
;
; Allocate memory for value string
;
pei (str+2) Get length of
pei (str) string to be
jsr cstrlen appended.
sta str_len
lda TempRBlen Get length of value.
bne notnull If 0,
inc a increment because "@" will be used.
notnull inc2 a Add 4 bytes for result buf len words.
inc2 a
clc Add length of string parameter.
adc str_len
sta buf_len Save result buf length.
inc a Add 1 more for terminating null byte.
pea 0
pha
~NEW Request the memory.
sta RVresult Store address in ReadVariable
stx RVresult+2 parameter block and
sta outPtr direct page pointer.
stx outPtr+2
ora outPtr+2 If address == NULL,
beq exit return NULL to user.
lda buf_len Store result buffer length
sta [outPtr] at beginning of buf.
;
; Read the full value into the allocated memory
;
ReadVariableGS ReadVar ReadVariable $HOME
bcs doAtSign If error, use @/
ldy #2 Get length of
lda [outPtr],y GS/OS string.
beq doAtSign If $HOME not defined, use "@".
clc
adc #4 Turn into a c-string
tay by storing a 0 byte
short m after the last $HOME
lda #0 character.
sta [outPtr],y
long m
bra doAppend
;
; $HOME is null string or not defined. Use @
;
doAtSign lda atSign
ldy #4
sta [outPtr],y
lda #1 Set GS/OS buffer
ldy #2 string length word
sta [outPtr],y to 1.
doAppend anop
ldy #4 Start index beyond length words.
short m
lp lda [outPtr],y
beq noSep
cmp #':'
beq foundSep
cmp #'/'
beq foundSep
iny
bra lp
noSep lda #':' No separator found; use ":".
foundSep sta [str] Store sep at start of appended string.
long m
pei (str+2)
pei (str)
ldx outPtr+2
lda outPtr
clc
adc #4
bcc pushptr
inx
pushptr phx
pha
case on
jsl strcat
case off
clc Add 2 bytes to address of
lda outPtr GS/OS output buffer to
adc #2 get address of GS/OS
bcc no_ovf input string.
inc outPtr+2
no_ovf sta outPtr
lda [outPtr] Adjust string length
clc to include appended
adc str_len string (parameter).
sta [outPtr]
;
; NOTE: The returned value points to a GS/OS string, two bytes offset
; from the allocated memory for a GS/OS result buffer. When the
; memory is deallocated, the address must be adjusted back.
;
exit unlock mutex
return 4:outPtr
mutex key
atSign dc c'@',i1'0'
;
; Parameter block for Shell call ReadVariable (p 423 in ORCA/M reference)
;
ReadVar anop
dc i2'3' pCount
dc a4'home' address of variable's name
RVresult ds 4 GS/OS Output buffer ptr
ds 2 export flag (returned)
;
; GS/OS result buffer for getting the full length of the HOME env var.
;
TempResultBuf dc i2'5' Only five bytes total.
TempRBlen ds 2 Value's length returned here.
ds 1 Only 1 byte for value.
;
; "HOME" as a GS/OS string
;
home gsstr 'HOME'
END
;=========================================================================
;
; GLOBAL data
;
;=========================================================================
global DATA
ID ds 2
GSOSDP ds 2
cmdloc ds 2
cmdlen ds 2
cmdline ds cmdbuflen
wordlen ds 2
nummatch ds 2
matchbuf ds 512*4
cmdcontext ds 2
cmddp ds 2
gshtty ds 2
gshpid ds 2
exit_requested dc i'0' ;!=0 if exit
signalled dc i'0'
done_init dc i2'0' 0 until init is complete
FastFlag dc i'0'
CmdFlag dc i'0'
CmdArgV ds 4
CmdArgC ds 2
ExecFlag dc i'0'
ExecCmd ds 4
END
;=========================================================================
;
; SIGINT handler when typed at command-line
;
;=========================================================================
signal2 START
using global
subroutine (4:fubar),0
WriteCString #msg
inc signalled
; ld2 $80,$E0C000
return
msg dc c'^C',h'0d0a00'
END
;=========================================================================
;
; SIGTSTP handler when typed at command-line
;
;=========================================================================
signal18 START
using global
subroutine (4:fubar),0
WriteCString #msg
inc signalled
; ld2 $80,$E0C000
return
msg dc c'^Z',h'0d0a00'
END