15955282f6
- ensure es = ds = ss upon exit of each C runtime function - clear upper 16 bits of ebx before setting them to 0x0021, when invoking interrupt_ptr to simulate a RM int 0x21 - make _sys_exists use the transfer buffer (which it needs) - make _sys_rawread properly handle an end-of-file read (zero bytes read) - make argument to _sys_seterrno short --- after a failed int 0x21 call, only the lower 16 bits of eax hold the MS-DOs error code - _sys_rawlseek accepts only 3 longword arguments, not 4 (the offset is only 1 longword) - other minor fixes
38 lines
473 B
ArmAsm
38 lines
473 B
ArmAsm
#
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! $Source$
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! $State$
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! $Revision$
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! Declare segments (the order is important).
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.sect .text
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.sect .rom
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.sect .data
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.sect .bss
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.sect .text
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! Say whether a file exists with the given name.
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.define __sys_exists
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__sys_exists:
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push esi
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mov esi, 4+4(esp)
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movzx edi, (transfer_buffer_ptr)
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mov edx, edi
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mov es, (pmode_ds)
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cld
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1:
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lodsb
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stosb
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testb al, al
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jnz 1b
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mov eax, 0x4300
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mov ebx, 0x210000
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callf (interrupt_ptr)
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push ss
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pop es
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sbb eax, eax
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inc eax
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ret
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