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   1 ;
   2 ; xcommon.s
   3 ;
   4 ; Common stuff for application and module stubs
   5 ;
   6 ; © 1993-1998 Straylight
   7 ;
   8
   9 ;----- Licensing note -------------------------------------------------------
  10 ;
  11 ; This file is part of Straylight's C library stubs (xstubs).
  12 ;
  13 ; xstubs is free software; you can redistribute it and/or modify
  14 ; it under the terms of the GNU General Public License as published by
  15 ; the Free Software Foundation; either version 2, or (at your option)
  16 ; any later version.
  17 ;
  18 ; xstubs is distributed in the hope that it will be useful,
  19 ; but WITHOUT ANY WARRANTY; without even the implied warranty of
  20 ; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21 ; GNU General Public License for more details.
  22 ;
  23 ; You should have received a copy of the GNU General Public License
  24 ; along with xstubs.  If not, write to the Free Software Foundation,
  25 ; 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  26
  27 ;----- Standard header ------------------------------------------------------
  28
  29                 GET     libs:header
  30
  31 ;----- External dependencies ------------------------------------------------
  32
  33                 IMPORT  |_clib_initialise|
  34                 IMPORT  |_main|
  35                 IMPORT  TrapHandler
  36                 IMPORT  UncaughtTrapHandler
  37                 IMPORT  EventHandler
  38                 IMPORT  UnhandledEventHandler
  39                 IMPORT  |_kernel_command_string|
  40                 IMPORT  |_stub_kallocExtendsWS|
  41                 IMPORT  |C$$code$$Base|
  42                 IMPORT  |C$$code$$Limit|
  43                 IMPORT  main,WEAK
  44                 IMPORT  |DLL$$ExternalTable$$Base|,WEAK
  45                 IMPORT  |DLL$$ExternalTable$$Limit|,WEAK
  46                 IMPORT  |_dll_findall|,WEAK
  47                 IMPORT  |_dll_appspace|,WEAK
  48                 IMPORT  |_dll_clibdata|,WEAK
  49                 IMPORT  |_dll_appEntryStubs|,WEAK
  50                 IMPORT  |_dll_appEntryNames|,WEAK
  51                 IMPORT  |_dll_regAppEntry|,WEAK
  52
  53 ;----- Run-time support information -----------------------------------------
  54
  55                 AREA    |RTSK$$Data|,CODE,READONLY
  56
  57 xstub__startDef DCD     xstub__endDef-xstub__startDef
  58                 DCD     |C$$code$$Base|
  59                 DCD     |C$$code$$Limit|
  60                 DCD     xstub__c
  61                 DCD     xstub__initC
  62                 DCD     0
  63                 DCD     TrapHandler
  64                 DCD     UncaughtTrapHandler
  65                 DCD     EventHandler
  66                 DCD     UnhandledEventHandler
  67 xstub__endDef
  68
  69 ;----- C library initialisation ---------------------------------------------
  70
  71                 AREA    |C$$code|,CODE,READONLY
  72
  73                 ; --- Magic numbers ---
  74
  75 xstub__c        DCB     "C",0                   ;Language name
  76                 ALIGN
  77
  78 xstub__initC    LDR     a1,=|_stub_kallocExtendsWS| ;Get flag offset
  79                 LDR     ip,[sl,#-536]           ;Get client reloc
  80                 ADD     a1,ip,a1                ;Relocate the offset
  81                 MOV     a2,#1                   ;Set the flag
  82                 STRB    a2,[a1]                 ;Yup.  Tha's it
  83                 STMFD   sp!,{lr}                ;Preserve link register
  84                 BL      |_clib_initialise|      ;Initialise C library
  85                 LDR     a1,=main                ;Try and find main routine
  86                 CMP     a1,#0                   ;Was it found?
  87                 ADRNE   a1,xstub__goGoGo        ;Insert own initialisation
  88                 LDMFD   sp!,{pc}^
  89
  90                 LTORG
  91
  92 xstub__goGoGo   MOV     ip,sp                   ;Standard stack frame stuff
  93                 STMFD   sp!,{fp,ip,lr,pc}
  94                 SUB     fp,ip,#4
  95
  96                 ; --- DLL initialisation stuff ---
  97                 ;
  98                 ; Find start and end of external DLL table.  If they're
  99                 ; equal, there's no table, and we don't care if the routine
 100                 ; to load them exists or not :-)
 101
 102                 LDR     a1,=|DLL$$ExternalTable$$Base|
 103                 LDR     a2,=|DLL$$ExternalTable$$Limit|
 104                 CMP     a1,a2
 105                 BEQ     appentry
 106                 BL      |_dll_findall|
 107                 BL      |_dll_appspace|
 108                 BL      |_dll_clibdata|
 109
 110                 ; Next, see if we can register the application as having
 111                 ; an external entry table.  If so, do it.
 112
 113 appentry        LDR     a1,=|_dll_appEntryStubs|
 114                 LDR     a2,=|_dll_appEntryNames|
 115                 CMP     a1,a2
 116                 BLNE    |_dll_regAppEntry|
 117
 118                 ; --- Start C program from main ---
 119
 120 nodlls          BL      |_kernel_command_string| ;Find the command line
 121                 LDR     R1,=main                ;Find user's main program
 122                 BL      |_main|                 ;Call it with correct args
 123                 LDMDB   fp,{fp,sp,pc}^
 124
 125                 LTORG
 126
 127 ;----- That's all for this one ----------------------------------------------
 128
 129                 END