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   1 ;
   2 ; oscli.s
   3 ;
   4 ; OSCLI and system support for DLLs and clients
   5 ;
   6 ; © 1994 Straylight
   7 ;
   8
   9 ;----- Standard header ------------------------------------------------------
  10
  11                 GET     libs:swis
  12                 GET     libs:header
  13
  14 ;----- External dependencies ------------------------------------------------
  15
  16                 IMPORT  system
  17                 IMPORT  |_kernel_system|
  18                 IMPORT  |x$stack_overflow|
  19
  20 ;----- Main code ------------------------------------------------------------
  21
  22                 AREA    |DLL$$Code|,CODE,READONLY
  23
  24 ; --- _dll_system ---
  25 ;
  26 ; On entry:     a1 == pointer to command line string (passed to system)
  27 ; On exit:      a1 == return code, as for system()
  28
  29                 EXPORT  |_dll_system|
  30 |_dll_system|   ROUT
  31
  32                 ; --- Standard APCS bit on the top ---
  33
  34                 MOV     ip,sp                   ;Keep current stack pointer
  35                 STMFD   sp!,{v1,v2,fp,ip,lr,pc} ;Create new stack frame
  36                 SUB     fp,ip,#4                ;Point fp at new stack frame
  37                 CMP     sp,sl                   ;Is there enough stack?
  38                 BLLT    |x$stack_overflow|      ;No -- create some more
  39
  40                 ; --- Preserve the old application handle ---
  41
  42                 MOV     v2,a1                   ;Preserve string pointer
  43                 SWI     DLL_SaveHandle          ;Get the current handle
  44                 MOV     v1,a1                   ;Preserve its value
  45
  46                 ; --- Call the actual command ---
  47
  48                 MOV     a1,v2                   ;Restore string pointer
  49                 BL      system                  ;Do whatever it is we do
  50
  51                 ; --- Restore the handle and exit ---
  52
  53                 MOV     v2,a1                   ;Keep hold of return value
  54                 MOV     a1,v1                   ;Transfer old handle
  55                 SWI     DLL_RestoreHandle       ;Set up the handle again
  56                 MOV     a1,v2                   ;Reinstate the return value
  57                 LDMDB   fp,{v1,v2,fp,sp,pc}^    ;Return to caller
  58
  59                 LTORG
  60
  61 ; --- _dll_ksystem ---
  62 ;
  63 ; On entry:     R0 == pointer to command to execute
  64 ;               R1 == 0 to run as a subprocess, nonzero to replace
  65 ; On exit:      >=0 for success, <0 for failure
  66
  67                 EXPORT  |_dll_ksystem|
  68 |_dll_ksystem|  ROUT
  69
  70                 ; --- Standard APCS bit on the top ---
  71
  72                 MOV     ip,sp                   ;Keep current stack pointer
  73                 STMFD   sp!,{v1,v2,fp,ip,lr,pc} ;Create new stack frame
  74                 SUB     fp,ip,#4                ;Point fp at new stack frame
  75                 CMP     sp,sl                   ;Is there enough stack?
  76                 BLLT    |x$stack_overflow|      ;No -- create some more
  77
  78                 ; --- Preserve the old application handle ---
  79
  80                 MOV     v2,a1                   ;Preserve string pointer
  81                 SWI     DLL_SaveHandle          ;Get the current handle
  82                 MOV     v1,a1                   ;Preserve its value
  83
  84                 ; --- Call the actual command ---
  85
  86                 MOV     a1,v2                   ;Restore string pointer
  87                 BL      |_kernel_system|        ;Do whatever it is we do
  88
  89                 ; --- Restore the handle and exit ---
  90
  91                 MOV     v2,a1                   ;Keep hold of return value
  92                 MOV     a1,v1                   ;Transfer old handle
  93                 SWI     DLL_RestoreHandle       ;Set up the handle again
  94                 MOV     a1,v2                   ;Reinstate the return value
  95                 LDMDB   fp,{v1,v2,fp,sp,pc}^    ;Return to caller
  96
  97                 LTORG
  98
  99 ; --- _dll_oscli ---
 100 ;
 101 ; On entry:     R0 == pointer to command string for OS_CLI
 102 ; On exit:      R0 == pointer to error, or 0
 103
 104                 EXPORT  |_dll_oscli|
 105 |_dll_oscli|    ROUT
 106
 107                 MOV     ip,lr                   ;Keep link register
 108                 MOV     a2,a1                   ;Keep pointer to string
 109                 SWI     DLL_SaveHandle          ;Get our current handle
 110                 MOV     a3,a1                   ;Save it away
 111                 MOV     a1,a2                   ;Restore pointer to command
 112                 SWI     XOS_CLI                 ;Do the actual command
 113                 MOVVS   a2,a1                   ;Save error ptr if it failed
 114                 MOVVC   a2,#0                   ;Otherwise remember it worked
 115                 MOV     a1,a3                   ;Restore the old handle
 116                 SWI     DLL_RestoreHandle       ;Resinstate the handle
 117                 MOV     a1,a2                   ;Point at error block
 118                 MOVS    pc,ip                   ;And return to caller
 119
 120                 LTORG
 121
 122 ; --- _dll_starttask ---
 123 ;
 124 ; On entry:     R0 == pointer to command to run as a separate task
 125 ; On exit:      R0 == pointer to error, or 0
 126
 127                 EXPORT  |_dll_starttask|
 128 |_dll_starttask| ROUT
 129
 130                 MOV     ip,lr                   ;Keep link register
 131                 MOV     a2,a1                   ;Keep pointer to string
 132                 SWI     DLL_SaveHandle          ;Get our current handle
 133                 MOV     a3,a1                   ;Save it away
 134                 MOV     a1,a2                   ;Restore pointer to command
 135                 SWI     XWimp_StartTask         ;Do the actual command
 136                 MOVVS   a2,a1                   ;Save error ptr if it failed
 137                 MOVVC   a2,#0                   ;Otherwise remember it worked
 138                 MOV     a1,a3                   ;Restore the old handle
 139                 SWI     DLL_RestoreHandle       ;Resinstate the handle
 140                 MOV     a1,a2                   ;Point at error block
 141                 MOVS    pc,ip                   ;And return to caller
 142
 143                 LTORG
 144
 145 ;----- That's all, folks ----------------------------------------------------
 146
 147                 END