diff options
| author | Kartik Agaram <vc@akkartik.com> | 2018-12-03 16:38:44 -0800 |
|---|---|---|
| committer | Kartik Agaram <vc@akkartik.com> | 2018-12-03 16:44:16 -0800 |
| commit | 5e27c7f13e6a888484ccf144579ed2d3b676da89 (patch) | |
| tree | 7763e7d04c2c0e1c374750777b0361b826401fdd | |
| parent | 5082923e81d331c2be12d6ec0be098bbd7ecf1c2 (diff) | |
| download | mu-5e27c7f13e6a888484ccf144579ed2d3b676da89.tar.gz | |
4827
I was 'returning' a phantom value from 'write' when the underlying '_write' returns nothing. In general, returning counts of bytes written is not so useful for error checking when my primitives abstract away from that. We'll come back to error signalling later.
| -rw-r--r-- | html/subx/056write.subx.html | 98 | ||||
| -rw-r--r-- | subx/056write.subx | 8 | ||||
| -rwxr-xr-x | subx/apps/crenshaw2-1 | bin | 6480 -> 6482 bytes | |||
| -rwxr-xr-x | subx/apps/crenshaw2-1b | bin | 7041 -> 7043 bytes | |||
| -rwxr-xr-x | subx/apps/factorial | bin | 5371 -> 5373 bytes |
5 files changed, 53 insertions, 53 deletions
diff --git a/html/subx/056write.subx.html b/html/subx/056write.subx.html index 7ada1e78..727bda6b 100644 --- a/html/subx/056write.subx.html +++ b/html/subx/056write.subx.html @@ -92,55 +92,55 @@ if ('onhashchange' in window) { <span id="L27" class="LineNr"> 27 </span> b8/copy-to-EAX 1/imm32 <span id="L28" class="LineNr"> 28 </span> cd/syscall 0x80/imm8 <span id="L29" class="LineNr"> 29 </span> -<span id="L30" class="LineNr"> 30 </span><span class="subxFunction">write</span>: <span class="subxComment"># f : fd or (address stream), s : (address array byte) -> bytes_written/EAX</span> -<span id="L31" class="LineNr"> 31 </span> <span class="subxComment"># (If we ever leave the Linux kernel behind, it may be better to return</span> -<span id="L32" class="LineNr"> 32 </span> <span class="subxComment"># the number of bytes *not* written. Success would then be signaled by</span> -<span id="L33" class="LineNr"> 33 </span> <span class="subxComment"># returning 0.)</span> -<span id="L34" class="LineNr"> 34 </span> <span class="subxS1Comment"># . prolog</span> -<span id="L35" class="LineNr"> 35 </span> 55/push-EBP -<span id="L36" class="LineNr"> 36 </span> 89/copy 3/mod/direct 5/rm32/EBP <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> 4/r32/ESP <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="subxComment"># copy ESP to EBP</span> -<span id="L37" class="LineNr"> 37 </span> <span class="subxComment"># if (f < 0x08000000) _write(f, s), return # f can't be a user-mode address, so treat it as a kernel file descriptor</span> -<span id="L38" class="LineNr"> 38 </span> 81 7/subop/compare 1/mod/*+disp8 4/rm32/sib 5/base/EBP 4/index/none <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> 8/disp8 0x08000000/imm32 <span class="subxComment"># compare *(EBP+8)</span> -<span id="L39" class="LineNr"> 39 </span> 7d/jump-if-greater-or-equal $write:fake/disp8 -<span id="L40" class="LineNr"> 40 </span> <span class="subxS2Comment"># . . push args</span> -<span id="L41" class="LineNr"> 41 </span> ff 6/subop/push 1/mod/*+disp8 4/rm32/sib 5/base/EBP 4/index/none <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> 0xc/disp8 <span class="CommentedCode"> . </span> <span class="subxComment"># push *(EBP+12)</span> -<span id="L42" class="LineNr"> 42 </span> ff 6/subop/push 1/mod/*+disp8 4/rm32/sib 5/base/EBP 4/index/none <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> 8/disp8 <span class="CommentedCode"> . </span> <span class="subxComment"># push *(EBP+8)</span> -<span id="L43" class="LineNr"> 43 </span> <span class="subxS2Comment"># . . call</span> -<span id="L44" class="LineNr"> 44 </span> e8/call _write/disp32 -<span id="L45" class="LineNr"> 45 </span> <span class="subxS2Comment"># . . discard args</span> -<span id="L46" class="LineNr"> 46 </span> 81 0/subop/add 3/mod/direct 4/rm32/ESP <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> 8/imm32 <span class="subxComment"># add to ESP</span> -<span id="L47" class="LineNr"> 47 </span> eb/jump $write:end/disp8 -<span id="L48" class="LineNr"> 48 </span><span class="Constant">$write:fake</span>: -<span id="L49" class="LineNr"> 49 </span> <span class="subxComment"># otherwise, treat 'f' as a stream to append to</span> -<span id="L50" class="LineNr"> 50 </span> <span class="subxS1Comment"># . save registers</span> -<span id="L51" class="LineNr"> 51 </span> 51/push-ECX -<span id="L52" class="LineNr"> 52 </span> 52/push-EDX -<span id="L53" class="LineNr"> 53 </span> 53/push-EBX -<span id="L54" class="LineNr"> 54 </span> <span class="subxComment"># ECX = f</span> -<span id="L55" class="LineNr"> 55 </span> 8b/copy 1/mod/*+disp8 4/rm32/sib 5/base/EBP 4/index/none 1/r32/ECX 8/disp8 <span class="CommentedCode"> . </span> <span class="subxComment"># copy *(EBP+8) to ECX</span> -<span id="L56" class="LineNr"> 56 </span> <span class="subxComment"># EDX = f->write</span> -<span id="L57" class="LineNr"> 57 </span> 8b/copy 0/mod/indirect 1/rm32/ECX <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> 2/r32/EDX <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="subxComment"># copy *ECX to EDX</span> -<span id="L58" class="LineNr"> 58 </span> <span class="subxComment"># EBX = f->length</span> -<span id="L59" class="LineNr"> 59 </span> 8b/copy 1/mod/*+disp8 1/rm32/ECX <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> 3/r32/EBX 8/disp8 <span class="CommentedCode"> . </span> <span class="subxComment"># copy *(ECX+8) to EBX</span> -<span id="L60" class="LineNr"> 60 </span> <span class="subxComment"># EAX = _append-3(&f->data[f->write], &f->data[f->length], s)</span> -<span id="L61" class="LineNr"> 61 </span> <span class="subxS2Comment"># . . push s</span> -<span id="L62" class="LineNr"> 62 </span> ff 6/subop/push 1/mod/*+disp8 4/rm32/sib 5/base/EBP 4/index/none <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> 0xc/disp8 <span class="CommentedCode"> . </span> <span class="subxComment"># push *(EBP+12)</span> -<span id="L63" class="LineNr"> 63 </span> <span class="subxS2Comment"># . . push &f->data[f->length]</span> -<span id="L64" class="LineNr"> 64 </span> 8d/copy-address 1/mod/*+disp8 4/rm32/sib 1/base/ECX 3/index/EBX <span class="CommentedCode"> . </span> 3/r32/EBX 0xc/disp8 <span class="CommentedCode"> . </span> <span class="subxComment"># copy ECX+EBX+12 to EBX</span> -<span id="L65" class="LineNr"> 65 </span> 53/push-EBX -<span id="L66" class="LineNr"> 66 </span> <span class="subxS2Comment"># . . push &f->data[f->write]</span> -<span id="L67" class="LineNr"> 67 </span> 8d/copy-address 1/mod/*+disp8 4/rm32/sib 1/base/ECX 2/index/EDX <span class="CommentedCode"> . </span> 3/r32/EBX 0xc/disp8 <span class="CommentedCode"> . </span> <span class="subxComment"># copy ECX+EDX+12 to EBX</span> -<span id="L68" class="LineNr"> 68 </span> 53/push-EBX -<span id="L69" class="LineNr"> 69 </span> <span class="subxS2Comment"># . . call</span> -<span id="L70" class="LineNr"> 70 </span> e8/call _append-3/disp32 -<span id="L71" class="LineNr"> 71 </span> <span class="subxS2Comment"># . . discard args</span> -<span id="L72" class="LineNr"> 72 </span> 81 0/subop/add 3/mod/direct 4/rm32/ESP <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> 0xc/imm32 <span class="subxComment"># add to ESP</span> -<span id="L73" class="LineNr"> 73 </span> <span class="subxComment"># f->write += EAX</span> -<span id="L74" class="LineNr"> 74 </span> 01/add 0/mod/indirect 1/rm32/ECX <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> 0/r32/EAX <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="subxComment"># add EAX to *ECX</span> -<span id="L75" class="LineNr"> 75 </span> <span class="subxS1Comment"># . restore registers</span> -<span id="L76" class="LineNr"> 76 </span> 5b/pop-to-EBX -<span id="L77" class="LineNr"> 77 </span> 5a/pop-to-EDX -<span id="L78" class="LineNr"> 78 </span> 59/pop-to-ECX +<span id="L30" class="LineNr"> 30 </span><span class="subxComment"># TODO: come up with a way to signal when a write to disk fails</span> +<span id="L31" class="LineNr"> 31 </span><span class="subxFunction">write</span>: <span class="subxComment"># f : fd or (address stream), s : (address array byte) -> <void></span> +<span id="L32" class="LineNr"> 32 </span> <span class="subxS1Comment"># . prolog</span> +<span id="L33" class="LineNr"> 33 </span> 55/push-EBP +<span id="L34" class="LineNr"> 34 </span> 89/copy 3/mod/direct 5/rm32/EBP <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> 4/r32/ESP <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="subxComment"># copy ESP to EBP</span> +<span id="L35" class="LineNr"> 35 </span> <span class="subxComment"># if (f < 0x08000000) _write(f, s), return # f can't be a user-mode address, so treat it as a kernel file descriptor</span> +<span id="L36" class="LineNr"> 36 </span> 81 7/subop/compare 1/mod/*+disp8 4/rm32/sib 5/base/EBP 4/index/none <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> 8/disp8 0x08000000/imm32 <span class="subxComment"># compare *(EBP+8)</span> +<span id="L37" class="LineNr"> 37 </span> 7d/jump-if-greater-or-equal $write:fake/disp8 +<span id="L38" class="LineNr"> 38 </span> <span class="subxS2Comment"># . . push args</span> +<span id="L39" class="LineNr"> 39 </span> ff 6/subop/push 1/mod/*+disp8 4/rm32/sib 5/base/EBP 4/index/none <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> 0xc/disp8 <span class="CommentedCode"> . </span> <span class="subxComment"># push *(EBP+12)</span> +<span id="L40" class="LineNr"> 40 </span> ff 6/subop/push 1/mod/*+disp8 4/rm32/sib 5/base/EBP 4/index/none <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> 8/disp8 <span class="CommentedCode"> . </span> <span class="subxComment"># push *(EBP+8)</span> +<span id="L41" class="LineNr"> 41 </span> <span class="subxS2Comment"># . . call</span> +<span id="L42" class="LineNr"> 42 </span> e8/call _write/disp32 +<span id="L43" class="LineNr"> 43 </span> <span class="subxS2Comment"># . . discard args</span> +<span id="L44" class="LineNr"> 44 </span> 81 0/subop/add 3/mod/direct 4/rm32/ESP <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> 8/imm32 <span class="subxComment"># add to ESP</span> +<span id="L45" class="LineNr"> 45 </span> eb/jump $write:end/disp8 +<span id="L46" class="LineNr"> 46 </span><span class="Constant">$write:fake</span>: +<span id="L47" class="LineNr"> 47 </span> <span class="subxComment"># otherwise, treat 'f' as a stream to append to</span> +<span id="L48" class="LineNr"> 48 </span> <span class="subxS1Comment"># . save registers</span> +<span id="L49" class="LineNr"> 49 </span> 50/push-EAX +<span id="L50" class="LineNr"> 50 </span> 51/push-ECX +<span id="L51" class="LineNr"> 51 </span> 52/push-EDX +<span id="L52" class="LineNr"> 52 </span> 53/push-EBX +<span id="L53" class="LineNr"> 53 </span> <span class="subxComment"># ECX = f</span> +<span id="L54" class="LineNr"> 54 </span> 8b/copy 1/mod/*+disp8 4/rm32/sib 5/base/EBP 4/index/none 1/r32/ECX 8/disp8 <span class="CommentedCode"> . </span> <span class="subxComment"># copy *(EBP+8) to ECX</span> +<span id="L55" class="LineNr"> 55 </span> <span class="subxComment"># EDX = f->write</span> +<span id="L56" class="LineNr"> 56 </span> 8b/copy 0/mod/indirect 1/rm32/ECX <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> 2/r32/EDX <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="subxComment"># copy *ECX to EDX</span> +<span id="L57" class="LineNr"> 57 </span> <span class="subxComment"># EBX = f->length</span> +<span id="L58" class="LineNr"> 58 </span> 8b/copy 1/mod/*+disp8 1/rm32/ECX <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> 3/r32/EBX 8/disp8 <span class="CommentedCode"> . </span> <span class="subxComment"># copy *(ECX+8) to EBX</span> +<span id="L59" class="LineNr"> 59 </span> <span class="subxComment"># EAX = _append-3(&f->data[f->write], &f->data[f->length], s)</span> +<span id="L60" class="LineNr"> 60 </span> <span class="subxS2Comment"># . . push s</span> +<span id="L61" class="LineNr"> 61 </span> ff 6/subop/push 1/mod/*+disp8 4/rm32/sib 5/base/EBP 4/index/none <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> 0xc/disp8 <span class="CommentedCode"> . </span> <span class="subxComment"># push *(EBP+12)</span> +<span id="L62" class="LineNr"> 62 </span> <span class="subxS2Comment"># . . push &f->data[f->length]</span> +<span id="L63" class="LineNr"> 63 </span> 8d/copy-address 1/mod/*+disp8 4/rm32/sib 1/base/ECX 3/index/EBX <span class="CommentedCode"> . </span> 3/r32/EBX 0xc/disp8 <span class="CommentedCode"> . </span> <span class="subxComment"># copy ECX+EBX+12 to EBX</span> +<span id="L64" class="LineNr"> 64 </span> 53/push-EBX +<span id="L65" class="LineNr"> 65 </span> <span class="subxS2Comment"># . . push &f->data[f->write]</span> +<span id="L66" class="LineNr"> 66 </span> 8d/copy-address 1/mod/*+disp8 4/rm32/sib 1/base/ECX 2/index/EDX <span class="CommentedCode"> . </span> 3/r32/EBX 0xc/disp8 <span class="CommentedCode"> . </span> <span class="subxComment"># copy ECX+EDX+12 to EBX</span> +<span id="L67" class="LineNr"> 67 </span> 53/push-EBX +<span id="L68" class="LineNr"> 68 </span> <span class="subxS2Comment"># . . call</span> +<span id="L69" class="LineNr"> 69 </span> e8/call _append-3/disp32 +<span id="L70" class="LineNr"> 70 </span> <span class="subxS2Comment"># . . discard args</span> +<span id="L71" class="LineNr"> 71 </span> 81 0/subop/add 3/mod/direct 4/rm32/ESP <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> 0xc/imm32 <span class="subxComment"># add to ESP</span> +<span id="L72" class="LineNr"> 72 </span> <span class="subxComment"># f->write += EAX</span> +<span id="L73" class="LineNr"> 73 </span> 01/add 0/mod/indirect 1/rm32/ECX <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> 0/r32/EAX <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="subxComment"># add EAX to *ECX</span> +<span id="L74" class="LineNr"> 74 </span> <span class="subxS1Comment"># . restore registers</span> +<span id="L75" class="LineNr"> 75 </span> 5b/pop-to-EBX +<span id="L76" class="LineNr"> 76 </span> 5a/pop-to-EDX +<span id="L77" class="LineNr"> 77 </span> 59/pop-to-ECX +<span id="L78" class="LineNr"> 78 </span> 58/pop-to-EAX <span id="L79" class="LineNr"> 79 </span><span class="Constant">$write:end</span>: <span id="L80" class="LineNr"> 80 </span> <span class="subxS1Comment"># . epilog</span> <span id="L81" class="LineNr"> 81 </span> 89/copy 3/mod/direct 4/rm32/ESP <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> 5/r32/EBP <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="subxComment"># copy EBP to ESP</span> diff --git a/subx/056write.subx b/subx/056write.subx index 3496d980..c76d0737 100644 --- a/subx/056write.subx +++ b/subx/056write.subx @@ -27,10 +27,8 @@ b8/copy-to-EAX 1/imm32 cd/syscall 0x80/imm8 -write: # f : fd or (address stream), s : (address array byte) -> bytes_written/EAX - # (If we ever leave the Linux kernel behind, it may be better to return - # the number of bytes *not* written. Success would then be signaled by - # returning 0.) +# TODO: come up with a way to signal when a write to disk fails +write: # f : fd or (address stream), s : (address array byte) -> <void> # . prolog 55/push-EBP 89/copy 3/mod/direct 5/rm32/EBP . . . 4/r32/ESP . . # copy ESP to EBP @@ -48,6 +46,7 @@ write: # f : fd or (address stream), s : (address array byte) -> bytes_written/ $write:fake: # otherwise, treat 'f' as a stream to append to # . save registers + 50/push-EAX 51/push-ECX 52/push-EDX 53/push-EBX @@ -76,6 +75,7 @@ $write:fake: 5b/pop-to-EBX 5a/pop-to-EDX 59/pop-to-ECX + 58/pop-to-EAX $write:end: # . epilog 89/copy 3/mod/direct 4/rm32/ESP . . . 5/r32/EBP . . # copy EBP to ESP diff --git a/subx/apps/crenshaw2-1 b/subx/apps/crenshaw2-1 index 47762af7..10003ae7 100755 --- a/subx/apps/crenshaw2-1 +++ b/subx/apps/crenshaw2-1 Binary files differdiff --git a/subx/apps/crenshaw2-1b b/subx/apps/crenshaw2-1b index 620c1bad..20eaafe0 100755 --- a/subx/apps/crenshaw2-1b +++ b/subx/apps/crenshaw2-1b Binary files differdiff --git a/subx/apps/factorial b/subx/apps/factorial index d3a50805..7d867940 100755 --- a/subx/apps/factorial +++ b/subx/apps/factorial Binary files differ |