# write-stream: like write, but write streams rather than strings == 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 #? Entry: # manual test #? # write-stream(stdout, _test-stream2) #? 68/push _test-stream2/imm32 #? 68/push 1/imm32/stdout #? e8/call write-stream/disp32 #? # syscall(exit, Num-test-failures) #? 8b/copy 0/mod/indirect 5/rm32/.disp32 . . 3/r32/ebx Num-test-failures/disp32 # copy *Num-test-failures to ebx #? e8/call syscall_exit/disp32 write-stream: # f: fd or (addr stream byte), s: (addr stream byte) # . prologue 55/push-ebp 89/copy 3/mod/direct 5/rm32/ebp . . . 4/r32/esp . . # copy esp to ebp # if (f < 0x08000000) _write-stream(f, s), return # f can't be a user-mode address, so treat it as a kernel file descriptor 81 7/subop/compare 1/mod/*+disp8 5/rm32/ebp . . . . 8/disp8 0x08000000/imm32 # compare *(ebp+8) 73/jump-if-addr>= $write-stream:fake/disp8 # . . push args ff 6/subop/push 1/mod/*+disp8 5/rm32/ebp . . . . 0xc/disp8 . # push *(ebp+12) ff 6/subop/push 1/mod/*+disp8 5/rm32/ebp . . . . 8/disp8 . # push *(ebp+8) # . . call e8/call _write-stream/disp32 # . . discard args 81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp eb/jump $write-stream:end/disp8 $write-stream:fake: # otherwise, treat 'f' as a stream to append to # . save registers 50/push-eax 56/push-esi 57/push-edi # edi = f 8b/copy 1/mod/*+disp8 5/rm32/ebp . . 7/r32/edi 8/disp8 . # copy *(ebp+8) to edi # esi = s 8b/copy 1/mod/*+disp8 5/rm32/ebp . . 6/r32/esi 0xc/disp8 . # copy *(ebp+12) to esi # eax = _append-4(&f->data[f->write], &f->data[f->size], &s->data[s->read], &s->data[s->write]) # . . push &s->data[s->write] 8b/copy 0/mod/indirect 6/rm32/esi . . . 0/r32/eax . . # copy *esi to eax 8d/copy-address 1/mod/*+disp8 4/rm32/sib 6/base/esi 0/index/eax . 0/r32/eax 0xc/disp8 . # copy esi+eax+12 to eax 50/push-eax # . . push &s->data[s->read] 8b/copy 1/mod/*+disp8 6/rm32/esi . . . 0/r32/eax 4/disp8 . # copy *(esi+4) to eax 8d/copy-address 1/mod/*+disp8 4/rm32/sib 6/base/esi 0/index/eax . 0/r32/eax 0xc/disp8 . # copy esi+eax+12 to eax 50/push-eax # . . push &f->data[f->size] 8b/copy 1/mod/*+disp8 7/rm32/edi . . . 0/r32/eax 8/disp8 . # copy *(edi+8) to eax 8d/copy-address 1/mod/*+disp8 4/rm32/sib 7/base/edi 0/index/eax . 0/r32/eax 0xc/disp8 . # copy edi+eax+12 to eax 50/push-eax # . . push &f->data[f->write] 8b/copy 0/mod/indirect 7/rm32/edi . . . 0/r32/eax . . # copy *edi to eax 8d/copy-address 1/mod/*+disp8 4/rm32/sib 7/base/edi 0/index/eax . 0/r32/eax 0xc/disp8 . # copy edi+eax+12 to eax 50/push-eax # . . call e8/call _append-4/disp32 # . . discard args 81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 0x10/imm32 # add to esp # f->write += eax 01/add 0/mod/indirect 7/rm32/edi . . . 0/r32/eax . . # add eax to *edi # s->read += eax 01/add 1/mod/*+disp8 6/rm32/esi . . . 0/r32/eax 4/disp8 . # add eax to *(esi+4) # . restore registers 5f/pop-to-edi 5e/pop-to-esi 58/pop-to-eax $write-stream:end: # . epilogue 89/copy 3/mod/direct 4/rm32/esp . . . 5/r32/ebp . . # copy ebp to esp 5d/pop-to-ebp c3/return _write-stream: # fd: int, s: (addr stream byte) # . 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 52/push-edx 53/push-ebx 56/push-esi 57/push-edi # esi = s 8b/copy 1/mod/*+disp8 5/rm32/ebp . . . 6/r32/esi 0xc/disp8 . # copy *(ebp+12) to esi # edi = s->read 8b/copy 1/mod/*+disp8 6/rm32/esi . . . 7/r32/edi 4/disp8 . # copy *(esi+4) to edi # edx = s->write 8b/copy 0/mod/indirect 6/rm32/esi . . . 2/r32/edx . . # copy *esi to edx # syscall(write, fd, &s->data[s->read], s->write - s->read) # . . fd: ebx 8b/copy 1/mod/*+disp8 5/rm32/ebp . . . 3/r32/ebx 8/disp8 . # copy *(ebp+8) to ebx # . . data: ecx = &s->data[s->read] 8d/copy-address 1/mod/*+disp8 4/rm32/sib 6/base/esi 7/index/edi . 1/r32/ecx 0xc/disp8 . # copy esi+edi+12 to ecx # . . size: edx = s->write - s->read 29/subtract 3/mod/direct 2/rm32/edx . . . 7/r32/edi . . # subtract edi from edx # . . syscall e8/call syscall_write/disp32 # if (eax < 0) abort 3d/compare-eax-with 0/imm32 0f 8c/jump-if-< $_write-stream:abort/disp32 # s->read += eax 01/add 1/mod/*+disp8 6/rm32/esi . . . 0/r32/eax 4/disp8 . # add eax to *(esi+4) # . restore registers 5f/pop-to-edi 5e/pop-to-esi 5b/pop-to-ebx 5a/pop-to-edx 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 $_write-stream:abort: # . _write(2/stderr, error) # . . push args 68/push "_write-stream: failed to write to file\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 e8/call syscall_exit/disp32 # never gets here test-write-stream-single: # 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-stream2) # . . push args 68/push _test-stream2/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(_test-stream2, "Ab") # . . push args 68/push "Ab"/imm32 68/push _test-stream2/imm32 # . . call e8/call write/disp32 # . . discard args 81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp # write-stream(_test-stream, _test-stream2) # . . push args 68/push _test-stream2/imm32 68/push _test-stream/imm32 # . . call e8/call write-stream/disp32 # . . discard args 81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp # check-stream-equal(_test-stream, "Ab", msg) # . . push args 68/push "F - test-write-stream-single"/imm32 68/push "Ab"/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-stream-appends: # 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-stream2) # . . push args 68/push _test-stream2/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(_test-stream2, "C") # . . push args 68/push "C"/imm32 68/push _test-stream2/imm32 # . . call e8/call write/disp32 # . . discard args 81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp # first write # . write-stream(_test-stream, _test-stream2) # . . push args 68/push _test-stream2/imm32 68/push _test-stream/imm32 # . . call e8/call write-stream/disp32 # . . discard args 81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp # second write # . write(_test-stream2, "D") # . . push args 68/push "D"/imm32 68/push _test-stream2/imm32 # . . call e8/call write/disp32 # . . discard args 81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp # . write-stream(_test-stream, _test-stream2) # . . push args 68/push _test-stream2/imm32 68/push _test-stream/imm32 # . . call e8/call write-stream/disp32 # . . discard args 81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp # check-stream-equal(_test-stream, "CD", msg) # . . push args 68/push "F - test-write-stream-appends"/imm32 68/push "CD"/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-stream2: # (stream byte) # current write index 4/imm32 # current read index 1/imm32 # size 8/imm32 # data 41/A 42/B 43/C 44/D 00 00 00 00 # 8 bytes # . . vim:nowrap:textwidth=0