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|
# write-byte-buffered: add a single byte to a buffered-file.
# flush: write out any buffered writes to disk.
#
# TODO: Come up with a way to signal failure to write to disk. This is hard
# since the failure may impact previous calls that were buffered.
== data
# The buffered file for standard output.
Stdout: # buffered-file
# file descriptor or (addr stream byte)
1/imm32 # standard output
$Stdout->buffer:
# inlined fields for a stream
# current write index
0/imm32
# current read index
0/imm32
# length
8/imm32
# data
00 00 00 00 00 00 00 00 # 8 bytes
# TODO: 8 bytes is too small. We'll need to grow the buffer for efficiency. But
# I don't want to type in 1024 bytes here.
== code
# instruction effective address register displacement immediate
# . op subop mod rm32 base index scale r32
# . 1-3 bytes 3 bits 2 bits 3 bits 3 bits 3 bits 2 bits 2 bits 0/1/2/4 bytes 0/1/2/4 bytes
# Write lower byte of 'n' to 'f'.
write-byte-buffered: # f: (addr buffered-file), n: int
# . prologue
55/push-ebp
89/copy 3/mod/direct 5/rm32/ebp . . . 4/r32/esp . . # copy esp to ebp
# . save registers
51/push-ecx
57/push-edi
# edi = f
8b/copy 1/mod/*+disp8 5/rm32/ebp . . . 7/r32/edi 8/disp8 . # copy *(ebp+8) to edi
# ecx = f->write
8b/copy 1/mod/*+disp8 7/rm32/edi . . . 1/r32/ecx 4/disp8 . # copy *(edi+4) to ecx
# if (f->write >= f->length) flush and clear f's stream
3b/compare 1/mod/*+disp8 7/rm32/edi . . . 1/r32/ecx 0xc/disp8 . # compare ecx with *(edi+12)
7c/jump-if-< $write-byte-buffered:to-stream/disp8
# . flush(f)
# . . push args
57/push-edi
# . . call
e8/call flush/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 4/imm32 # add to esp
# . clear-stream(stream = f+4)
# . . push args
8d/copy-address 1/mod/*+disp8 7/rm32/edi . . . 0/r32/eax 4/disp8 . # copy edi+4 to eax
50/push-eax
# . . call
e8/call clear-stream/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 4/imm32 # add to esp
# . f->write must now be 0; update its cache at ecx
31/xor 3/mod/direct 1/rm32/ecx . . . 1/r32/ecx . . # clear ecx
$write-byte-buffered:to-stream:
# write to stream
# f->data[f->write] = LSB(n)
31/xor 3/mod/direct 0/rm32/eax . . . 0/r32/eax . . # clear eax
8a/copy-byte 1/mod/*+disp8 5/rm32/ebp . . . 0/r32/AL 0xc/disp8 . # copy byte at *(ebp+12) to AL
88/copy-byte 1/mod/*+disp8 4/rm32/sib 7/base/edi 1/index/ecx . 0/r32/AL 0x10/disp8 . # copy AL to *(edi+ecx+16)
# ++f->write
ff 0/subop/increment 1/mod/*+disp8 7/rm32/edi . . . . 4/disp8 . # increment *(edi+4)
$write-byte-buffered:end:
# . restore registers
5f/pop-to-edi
59/pop-to-ecx
# . epilogue
89/copy 3/mod/direct 4/rm32/esp . . . 5/r32/ebp . . # copy ebp to esp
5d/pop-to-ebp
c3/return
flush: # f: (addr buffered-file)
# . prologue
55/push-ebp
89/copy 3/mod/direct 5/rm32/ebp . . . 4/r32/esp . . # copy esp to ebp
# . save registers
50/push-eax
51/push-ecx
# eax = f
8b/copy 1/mod/*+disp8 5/rm32/ebp . . . 0/r32/eax 8/disp8 . # copy *(ebp+8) to eax
# write-stream(f->fd, data = f+4)
# . . push args
8d/copy-address 1/mod/*+disp8 0/rm32/eax . . . 1/r32/ecx 4/disp8 . # copy eax+4 to ecx
51/push-ecx
ff 6/subop/push 0/mod/indirect 0/rm32/eax . . . . . . # push *eax
# . . call
e8/call write-stream/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp
$flush:end:
# . restore registers
59/pop-to-ecx
58/pop-to-eax
# . epilogue
89/copy 3/mod/direct 4/rm32/esp . . . 5/r32/ebp . . # copy ebp to esp
5d/pop-to-ebp
c3/return
test-write-byte-buffered-single:
# - check that write-byte-buffered writes to first byte of 'file'
# setup
# . clear-stream(_test-stream)
# . . push args
68/push _test-stream/imm32
# . . call
e8/call clear-stream/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 4/imm32 # add to esp
# . clear-stream($_test-buffered-file->buffer)
# . . push args
68/push $_test-buffered-file->buffer/imm32
# . . call
e8/call clear-stream/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 4/imm32 # add to esp
# write-byte-buffered(_test-buffered-file, 'A')
# . . push args
68/push 0x41/imm32
68/push _test-buffered-file/imm32
# . . call
e8/call write-byte-buffered/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp
# flush(_test-buffered-file)
# . . push args
68/push _test-buffered-file/imm32
# . . call
e8/call flush/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 4/imm32 # add to esp
# check-stream-equal(_test-stream, "A", msg)
# . . push args
68/push "F - test-write-byte-buffered-single"/imm32
68/push "A"/imm32
68/push _test-stream/imm32
# . . call
e8/call check-stream-equal/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 0xc/imm32 # add to esp
# . end
c3/return
test-write-byte-buffered-multiple-flushes:
# - check that write-byte-buffered correctly flushes buffered data
# setup
# . clear-stream(_test-stream)
# . . push args
68/push _test-stream/imm32
# . . call
e8/call clear-stream/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 4/imm32 # add to esp
# . clear-stream($_test-buffered-file->buffer)
# . . push args
68/push $_test-buffered-file->buffer/imm32
# . . call
e8/call clear-stream/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 4/imm32 # add to esp
# fill up the buffer for _test-buffered-file
# . write($_test-buffered-file->buffer, "abcdef")
# . . push args
68/push "abcdef"/imm32
68/push $_test-buffered-file->buffer/imm32
# . . call
e8/call write/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp
# write-byte-buffered(_test-buffered-file, 'g')
# . . push args
68/push 0x67/imm32
68/push _test-buffered-file/imm32
# . . call
e8/call write-byte-buffered/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp
# flush(_test-buffered-file)
# . . push args
68/push _test-buffered-file/imm32
# . . call
e8/call flush/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 4/imm32 # add to esp
# check-stream-equal(_test-stream, "abcdefg", msg)
# . . push args
68/push "F - test-write-byte-buffered-multiple-flushes"/imm32
68/push "abcdefg"/imm32
68/push _test-stream/imm32
# . . call
e8/call check-stream-equal/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 0xc/imm32 # add to esp
# . end
c3/return
# - variant without buffering
# Write lower byte of 'n' to 'f'.
append-byte: # f: (addr stream byte), n: int
# . prologue
55/push-ebp
89/copy 3/mod/direct 5/rm32/ebp . . . 4/r32/esp . . # copy esp to ebp
# . save registers
51/push-ecx
57/push-edi
# edi = f
8b/copy 1/mod/*+disp8 5/rm32/ebp . . . 7/r32/edi 8/disp8 . # copy *(ebp+8) to edi
# ecx = f->write
8b/copy 0/mod/indirect 7/rm32/edi . . . 1/r32/ecx . . # copy *edi to ecx
# if (f->write >= f->length) abort
3b/compare 1/mod/*+disp8 7/rm32/edi . . . 1/r32/ecx 8/disp8 . # compare ecx with *(edi+8)
7d/jump-if->= $append-byte:abort/disp8
$append-byte:to-stream:
# write to stream
# f->data[f->write] = LSB(n)
31/xor 3/mod/direct 0/rm32/eax . . . 0/r32/eax . . # clear eax
8a/copy-byte 1/mod/*+disp8 5/rm32/ebp . . . 0/r32/AL 0xc/disp8 . # copy byte at *(ebp+12) to AL
88/copy-byte 1/mod/*+disp8 4/rm32/sib 7/base/edi 1/index/ecx . 0/r32/AL 0xc/disp8 . # copy AL to *(edi+ecx+12)
# ++f->write
ff 0/subop/increment 0/mod/indirect 7/rm32/edi . . . . . . # increment *edi
$append-byte:end:
# . restore registers
5f/pop-to-edi
59/pop-to-ecx
# . epilogue
89/copy 3/mod/direct 4/rm32/esp . . . 5/r32/ebp . . # copy ebp to esp
5d/pop-to-ebp
c3/return
$append-byte:abort:
# . _write(2/stderr, error)
# . . push args
68/push "append-byte: out of space\n"/imm32
68/push 2/imm32/stderr
# . . call
e8/call _write/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp
# . syscall(exit, 1)
bb/copy-to-ebx 1/imm32
b8/copy-to-eax 1/imm32/exit
cd/syscall 0x80/imm8
# never gets here
test-append-byte-single:
# - check that append-byte writes to first byte of 'file'
# setup
# . clear-stream(_test-stream)
# . . push args
68/push _test-stream/imm32
# . . call
e8/call clear-stream/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 4/imm32 # add to esp
# append-byte(_test-stream, 'A')
# . . push args
68/push 0x41/imm32
68/push _test-stream/imm32
# . . call
e8/call append-byte/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp
# check-stream-equal(_test-stream, "A", msg)
# . . push args
68/push "F - test-append-byte-single"/imm32
68/push "A"/imm32
68/push _test-stream/imm32
# . . call
e8/call check-stream-equal/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 0xc/imm32 # add to esp
# . end
c3/return
== data
_test-output-stream: # (stream byte)
# current write index
0/imm32
# current read index
0/imm32
# length
0x400/imm32 # 1024 bytes
# data (64 lines x 16 bytes/line)
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
# a test buffered file for _test-output-stream
_test-output-buffered-file: # buffered-file
# file descriptor or (addr stream byte)
_test-output-stream/imm32
$_test-output-buffered-file->buffer:
# current write index
0/imm32
# current read index
0/imm32
# length
6/imm32
# data
00 00 00 00 00 00 # 6 bytes
_test-error-stream: # (stream byte)
# current write index
0/imm32
# current read index
0/imm32
# line
0x80/imm32 # 128 bytes
# data (8 lines x 16 bytes/line)
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
# a test buffered file for _test-error-stream
_test-error-buffered-file: # buffered-file
# file descriptor or (addr stream byte)
_test-error-stream/imm32
$_test-error-buffered-file->buffer:
# current write index
0/imm32
# current read index
0/imm32
# length
6/imm32
# data
00 00 00 00 00 00 # 6 bytes
# . . vim:nowrap:textwidth=0
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