diff options
| author | Kartik Agaram <vc@akkartik.com> | 2018-12-03 11:42:04 -0800 |
|---|---|---|
| committer | Kartik Agaram <vc@akkartik.com> | 2018-12-03 11:42:04 -0800 |
| commit | 26efb5f5c2a3ddbaf82f06e6ca6090caf7ab5a16 (patch) | |
| tree | 5f7883b01cc3051cc436937310664bb6b1387ef2 | |
| parent | 1eb9cc5679ed70dd2e4eceab8f3a547c8560aeba (diff) | |
| download | mu-26efb5f5c2a3ddbaf82f06e6ca6090caf7ab5a16.tar.gz | |
4823
| -rw-r--r-- | html/subx/059read-byte.subx.html | 453 | ||||
| -rw-r--r-- | subx/059read-byte.subx | 6 |
2 files changed, 229 insertions, 230 deletions
diff --git a/html/subx/059read-byte.subx.html b/html/subx/059read-byte.subx.html index c84c5d25..ad958670 100644 --- a/html/subx/059read-byte.subx.html +++ b/html/subx/059read-byte.subx.html @@ -90,232 +90,233 @@ if ('onhashchange' in window) { <span id="L24" class="LineNr"> 24 </span> <span class="subxComment"># data</span> <span id="L25" class="LineNr"> 25 </span> 00 00 00 00 00 00 00 00 <span class="subxComment"># 8 bytes</span> <span id="L26" class="LineNr"> 26 </span> -<span id="L27" class="LineNr"> 27 </span><span class="subxComment"># TODO: 8 bytes is too small. We'll need to grow the buffer for efficiency.</span> -<span id="L28" class="LineNr"> 28 </span> -<span id="L29" class="LineNr"> 29 </span>== code -<span id="L30" class="LineNr"> 30 </span><span class="subxComment"># instruction effective address register displacement immediate</span> -<span id="L31" class="LineNr"> 31 </span><span class="subxS1Comment"># . op subop mod rm32 base index scale r32</span> -<span id="L32" class="LineNr"> 32 </span><span class="subxS1Comment"># . 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</span> -<span id="L33" class="LineNr"> 33 </span> -<span id="L34" class="LineNr"> 34 </span><span class="subxComment"># main:</span> -<span id="L35" class="LineNr"> 35 </span> e8/call run-tests/disp32 <span class="subxComment"># 'run-tests' is a function created automatically by SubX. It calls all functions that start with 'test-'.</span> -<span id="L36" class="LineNr"> 36 </span><span class="CommentedCode">#? e8/call test-read-byte-multiple/disp32</span> -<span id="L37" class="LineNr"> 37 </span> <span class="subxComment"># syscall(exit, Num-test-failures)</span> -<span id="L38" class="LineNr"> 38 </span> 8b/copy 0/mod/indirect 5/rm32/.disp32 <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> 3/r32/EBX <span class="SpecialChar">Num-test-failures</span>/disp32 <span class="subxComment"># copy *Num-test-failures to EBX</span> -<span id="L39" class="LineNr"> 39 </span> b8/copy-to-EAX 1/imm32 -<span id="L40" class="LineNr"> 40 </span> cd/syscall 0x80/imm8 -<span id="L41" class="LineNr"> 41 </span> -<span id="L42" class="LineNr"> 42 </span><span class="subxComment"># return next byte value in EAX, with top 3 bytes cleared.</span> -<span id="L43" class="LineNr"> 43 </span><span class="subxComment"># On EOF, return 0xffffffff.</span> -<span id="L44" class="LineNr"> 44 </span><span class="subxFunction">read-byte</span>: <span class="subxComment"># f : (address buffered-file) -> byte-or-eof/EAX</span> -<span id="L45" class="LineNr"> 45 </span> <span class="subxS1Comment"># . prolog</span> -<span id="L46" class="LineNr"> 46 </span> 55/push-EBP -<span id="L47" class="LineNr"> 47 </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="L48" class="LineNr"> 48 </span> <span class="subxS1Comment"># . save registers</span> -<span id="L49" class="LineNr"> 49 </span> 51/push-ECX -<span id="L50" class="LineNr"> 50 </span> 56/push-ESI -<span id="L51" class="LineNr"> 51 </span> <span class="subxComment"># ESI = f</span> -<span id="L52" class="LineNr"> 52 </span> 8b/copy 1/mod/*+disp8 4/rm32/sib 5/base/EBP 4/index/none <span class="CommentedCode"> . </span> 6/r32/ESI 8/disp8 <span class="CommentedCode"> . </span> <span class="subxComment"># copy *(EBP+8) to ESI</span> -<span id="L53" class="LineNr"> 53 </span> <span class="subxComment"># ECX = f->read</span> -<span id="L54" class="LineNr"> 54 </span> 8b/copy 1/mod/*+disp8 6/rm32/ESI <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> 1/r32/ECX 8/disp8 <span class="CommentedCode"> . </span> <span class="subxComment"># copy *(ESI+8) to ECX</span> -<span id="L55" class="LineNr"> 55 </span> <span class="subxComment"># if (f->read < f->write) read byte from stream</span> -<span id="L56" class="LineNr"> 56 </span> 3b/compare 1/mod/*+disp8 6/rm32/ESI <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> 1/r32/ECX 4/disp8 <span class="CommentedCode"> . </span> <span class="subxComment"># compare ECX with *(ESI+4)</span> -<span id="L57" class="LineNr"> 57 </span> 7c/jump-if-lesser $read-byte:from-stream/disp8 -<span id="L58" class="LineNr"> 58 </span> <span class="subxComment"># otherwise first populate stream from file</span> -<span id="L59" class="LineNr"> 59 </span> <span class="subxS1Comment"># . clear-stream(stream = f+4)</span> -<span id="L60" class="LineNr"> 60 </span> <span class="subxS2Comment"># . . push args</span> -<span id="L61" class="LineNr"> 61 </span> 8d/copy-address 1/mod/*+disp8 6/rm32/ESI <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> 0/r32/EAX 4/disp8 <span class="CommentedCode"> . </span> <span class="subxComment"># copy ESI+4 to EAX</span> -<span id="L62" class="LineNr"> 62 </span> 50/push-EAX -<span id="L63" class="LineNr"> 63 </span> <span class="subxS2Comment"># . . call</span> -<span id="L64" class="LineNr"> 64 </span> e8/call clear-stream/disp32 -<span id="L65" class="LineNr"> 65 </span> <span class="subxS2Comment"># . . discard args</span> -<span id="L66" class="LineNr"> 66 </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> 4/imm32 <span class="subxComment"># add to ESP</span> -<span id="L67" class="LineNr"> 67 </span> <span class="subxS1Comment"># . EAX = read(f->fd, stream = f+4)</span> -<span id="L68" class="LineNr"> 68 </span> <span class="subxS2Comment"># . . push args</span> -<span id="L69" class="LineNr"> 69 </span> 50/push-EAX -<span id="L70" class="LineNr"> 70 </span> ff 6/subop/push 0/mod/indirect 6/rm32/ESI <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="subxComment"># push *ESI</span> -<span id="L71" class="LineNr"> 71 </span> <span class="subxS2Comment"># . . call</span> -<span id="L72" class="LineNr"> 72 </span> e8/call read/disp32 -<span id="L73" class="LineNr"> 73 </span> <span class="subxS2Comment"># . . discard args</span> -<span id="L74" class="LineNr"> 74 </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="L75" class="LineNr"> 75 </span> <span class="subxComment"># if EAX = 0 return 0xffffffff</span> -<span id="L76" class="LineNr"> 76 </span> 81 7/subop/compare 3/mod/direct 0/rm32/EAX <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> 0/imm32 <span class="subxComment"># compare EAX</span> -<span id="L77" class="LineNr"> 77 </span> 75/jump-if-not-equal $read-byte:from-stream/disp8 -<span id="L78" class="LineNr"> 78 </span> b8/copy-to-EAX 0xffffffff/imm32 -<span id="L79" class="LineNr"> 79 </span> eb/jump $read-byte:end/disp8 -<span id="L80" class="LineNr"> 80 </span><span class="Constant">$read-byte:from-stream</span>: -<span id="L81" class="LineNr"> 81 </span> <span class="subxComment"># reading from stream</span> -<span id="L82" class="LineNr"> 82 </span> <span class="subxComment"># AL = f->data[f->read]</span> -<span id="L83" class="LineNr"> 83 </span> 31/xor 3/mod/direct 0/rm32/EAX <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"># clear EAX</span> -<span id="L84" class="LineNr"> 84 </span> 8a/copy-byte 1/mod/*+disp8 4/rm32/sib 6/base/ESI 1/index/ECX <span class="CommentedCode"> . </span> 0/r32/AL 0x10/disp8 <span class="CommentedCode"> . </span> <span class="subxComment"># copy *(ESI+ECX+16) to AL</span> -<span id="L85" class="LineNr"> 85 </span> <span class="subxComment"># ++f->read</span> -<span id="L86" class="LineNr"> 86 </span> ff 0/subop/increment 1/mod/*+disp8 6/rm32/ESI <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> 8/disp8 <span class="CommentedCode"> . </span> <span class="subxComment"># increment *(ESI+8)</span> -<span id="L87" class="LineNr"> 87 </span><span class="Constant">$read-byte:end</span>: -<span id="L88" class="LineNr"> 88 </span> <span class="subxS1Comment"># . restore registers</span> -<span id="L89" class="LineNr"> 89 </span> 5e/pop-to-ESI -<span id="L90" class="LineNr"> 90 </span> 59/pop-to-ECX -<span id="L91" class="LineNr"> 91 </span> <span class="subxS1Comment"># . epilog</span> -<span id="L92" class="LineNr"> 92 </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> -<span id="L93" class="LineNr"> 93 </span> 5d/pop-to-EBP -<span id="L94" class="LineNr"> 94 </span> c3/return -<span id="L95" class="LineNr"> 95 </span> -<span id="L96" class="LineNr"> 96 </span><span class="subxComment"># todo: how should write-byte look? What should it do when the output has no</span> -<span id="L97" class="LineNr"> 97 </span><span class="subxComment"># space remaining? Maybe return an error code.</span> -<span id="L98" class="LineNr"> 98 </span> -<span id="L99" class="LineNr"> 99 </span><span class="subxH1Comment"># - tests</span> -<span id="L100" class="LineNr">100 </span> -<span id="L101" class="LineNr">101 </span><span class="subxTest">test-read-byte-single</span>: -<span id="L102" class="LineNr">102 </span> <span class="subxH1Comment"># - check that read-byte returns first byte of 'file'</span> -<span id="L103" class="LineNr">103 </span> <span class="subxComment"># setup</span> -<span id="L104" class="LineNr">104 </span> <span class="subxS1Comment"># . clear-stream(_test-stream)</span> -<span id="L105" class="LineNr">105 </span> <span class="subxS2Comment"># . . push args</span> -<span id="L106" class="LineNr">106 </span> 68/push _test-stream/imm32 -<span id="L107" class="LineNr">107 </span> <span class="subxS2Comment"># . . call</span> -<span id="L108" class="LineNr">108 </span> e8/call clear-stream/disp32 -<span id="L109" class="LineNr">109 </span> <span class="subxS2Comment"># . . discard args</span> -<span id="L110" class="LineNr">110 </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> 4/imm32 <span class="subxComment"># add to ESP</span> -<span id="L111" class="LineNr">111 </span> <span class="subxS1Comment"># . clear-stream(_test-buffered-file+4)</span> -<span id="L112" class="LineNr">112 </span> <span class="subxS2Comment"># . . push args</span> -<span id="L113" class="LineNr">113 </span> b8/copy-to-EAX _test-buffered-file/imm32 -<span id="L114" class="LineNr">114 </span> 05/add-to-EAX 4/imm32 -<span id="L115" class="LineNr">115 </span> 50/push-EAX -<span id="L116" class="LineNr">116 </span> <span class="subxS2Comment"># . . call</span> -<span id="L117" class="LineNr">117 </span> e8/call clear-stream/disp32 -<span id="L118" class="LineNr">118 </span> <span class="subxS2Comment"># . . discard args</span> -<span id="L119" class="LineNr">119 </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> 4/imm32 <span class="subxComment"># add to ESP</span> -<span id="L120" class="LineNr">120 </span> <span class="subxS1Comment"># . write(_test-stream, "Ab")</span> -<span id="L121" class="LineNr">121 </span> <span class="subxS2Comment"># . . push args</span> -<span id="L122" class="LineNr">122 </span> 68/push <span class="Constant">"Ab"</span>/imm32 -<span id="L123" class="LineNr">123 </span> 68/push _test-stream/imm32 -<span id="L124" class="LineNr">124 </span> <span class="subxS2Comment"># . . call</span> -<span id="L125" class="LineNr">125 </span> e8/call write/disp32 -<span id="L126" class="LineNr">126 </span> <span class="subxS2Comment"># . . discard args</span> -<span id="L127" class="LineNr">127 </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="L128" class="LineNr">128 </span> <span class="subxComment"># read-byte(_test-buffered-file)</span> -<span id="L129" class="LineNr">129 </span> <span class="subxS2Comment"># . . push args</span> -<span id="L130" class="LineNr">130 </span> 68/push _test-buffered-file/imm32 -<span id="L131" class="LineNr">131 </span> <span class="subxS2Comment"># . . call</span> -<span id="L132" class="LineNr">132 </span> e8/call read-byte/disp32 -<span id="L133" class="LineNr">133 </span> <span class="subxS2Comment"># . . discard args</span> -<span id="L134" class="LineNr">134 </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> 4/imm32 <span class="subxComment"># add to ESP</span> -<span id="L135" class="LineNr">135 </span> <span class="subxComment"># check-ints-equal(EAX, 'A', msg)</span> -<span id="L136" class="LineNr">136 </span> <span class="subxS2Comment"># . . push args</span> -<span id="L137" class="LineNr">137 </span> 68/push <span class="Constant">"F - test-read-byte-single"</span>/imm32 -<span id="L138" class="LineNr">138 </span> 68/push 0x41/imm32 -<span id="L139" class="LineNr">139 </span> 50/push-EAX -<span id="L140" class="LineNr">140 </span> <span class="subxS2Comment"># . . call</span> -<span id="L141" class="LineNr">141 </span> e8/call check-ints-equal/disp32 -<span id="L142" class="LineNr">142 </span> <span class="subxS2Comment"># . . discard args</span> -<span id="L143" class="LineNr">143 </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="L144" class="LineNr">144 </span> <span class="subxS1Comment"># . end</span> -<span id="L145" class="LineNr">145 </span> c3/return -<span id="L146" class="LineNr">146 </span> -<span id="L147" class="LineNr">147 </span><span class="subxTest">test-read-byte-multiple</span>: -<span id="L148" class="LineNr">148 </span> <span class="subxH1Comment"># - call read-byte twice, check that second call returns second byte</span> -<span id="L149" class="LineNr">149 </span> <span class="subxComment"># setup</span> -<span id="L150" class="LineNr">150 </span> <span class="subxS1Comment"># . clear-stream(_test-stream)</span> -<span id="L151" class="LineNr">151 </span> <span class="subxS2Comment"># . . push args</span> -<span id="L152" class="LineNr">152 </span> 68/push _test-stream/imm32 -<span id="L153" class="LineNr">153 </span> <span class="subxS2Comment"># . . call</span> -<span id="L154" class="LineNr">154 </span> e8/call clear-stream/disp32 -<span id="L155" class="LineNr">155 </span> <span class="subxS2Comment"># . . discard args</span> -<span id="L156" class="LineNr">156 </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> 4/imm32 <span class="subxComment"># add to ESP</span> -<span id="L157" class="LineNr">157 </span> <span class="subxS1Comment"># . clear-stream(_test-buffered-file+4)</span> -<span id="L158" class="LineNr">158 </span> <span class="subxS2Comment"># . . push args</span> -<span id="L159" class="LineNr">159 </span> b8/copy-to-EAX _test-buffered-file/imm32 -<span id="L160" class="LineNr">160 </span> 05/add-to-EAX 4/imm32 -<span id="L161" class="LineNr">161 </span> 50/push-EAX -<span id="L162" class="LineNr">162 </span> <span class="subxS2Comment"># . . call</span> -<span id="L163" class="LineNr">163 </span> e8/call clear-stream/disp32 -<span id="L164" class="LineNr">164 </span> <span class="subxS2Comment"># . . discard args</span> -<span id="L165" class="LineNr">165 </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> 4/imm32 <span class="subxComment"># add to ESP</span> -<span id="L166" class="LineNr">166 </span> <span class="subxS1Comment"># . write(_test-stream, "Ab")</span> -<span id="L167" class="LineNr">167 </span> <span class="subxS2Comment"># . . push args</span> -<span id="L168" class="LineNr">168 </span> 68/push <span class="Constant">"Ab"</span>/imm32 -<span id="L169" class="LineNr">169 </span> 68/push _test-stream/imm32 -<span id="L170" class="LineNr">170 </span> <span class="subxS2Comment"># . . call</span> -<span id="L171" class="LineNr">171 </span> e8/call write/disp32 -<span id="L172" class="LineNr">172 </span> <span class="subxS2Comment"># . . discard args</span> -<span id="L173" class="LineNr">173 </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="L174" class="LineNr">174 </span> <span class="subxComment"># read-byte(_test-buffered-file)</span> -<span id="L175" class="LineNr">175 </span> <span class="subxS2Comment"># . . push args</span> -<span id="L176" class="LineNr">176 </span> 68/push _test-buffered-file/imm32 -<span id="L177" class="LineNr">177 </span> <span class="subxS2Comment"># . . call</span> -<span id="L178" class="LineNr">178 </span> e8/call read-byte/disp32 -<span id="L179" class="LineNr">179 </span> <span class="subxS2Comment"># . . discard args</span> -<span id="L180" class="LineNr">180 </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> 4/imm32 <span class="subxComment"># add to ESP</span> -<span id="L181" class="LineNr">181 </span> <span class="subxComment"># read-byte(_test-buffered-file)</span> -<span id="L182" class="LineNr">182 </span> <span class="subxS2Comment"># . . push args</span> -<span id="L183" class="LineNr">183 </span> 68/push _test-buffered-file/imm32 -<span id="L184" class="LineNr">184 </span> <span class="subxS2Comment"># . . call</span> -<span id="L185" class="LineNr">185 </span> e8/call read-byte/disp32 -<span id="L186" class="LineNr">186 </span> <span class="subxS2Comment"># . . discard args</span> -<span id="L187" class="LineNr">187 </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> 4/imm32 <span class="subxComment"># add to ESP</span> -<span id="L188" class="LineNr">188 </span> <span class="subxComment"># check-ints-equal(EAX, 'b', msg)</span> -<span id="L189" class="LineNr">189 </span> <span class="subxS2Comment"># . . push args</span> -<span id="L190" class="LineNr">190 </span> 68/push <span class="Constant">"F - test-read-byte-multiple"</span>/imm32 -<span id="L191" class="LineNr">191 </span> 68/push 0x62/imm32 -<span id="L192" class="LineNr">192 </span> 50/push-EAX -<span id="L193" class="LineNr">193 </span> <span class="subxS2Comment"># . . call</span> -<span id="L194" class="LineNr">194 </span> e8/call check-ints-equal/disp32 -<span id="L195" class="LineNr">195 </span> <span class="subxS2Comment"># . . discard args</span> -<span id="L196" class="LineNr">196 </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="L197" class="LineNr">197 </span> <span class="subxS1Comment"># . end</span> -<span id="L198" class="LineNr">198 </span> c3/return -<span id="L199" class="LineNr">199 </span> -<span id="L200" class="LineNr">200 </span><span class="subxTest">test-read-byte-end-of-file</span>: -<span id="L201" class="LineNr">201 </span> <span class="subxH1Comment"># - call read-byte on an empty 'file', check that it returns -1</span> -<span id="L202" class="LineNr">202 </span> <span class="subxComment"># setup</span> -<span id="L203" class="LineNr">203 </span> <span class="subxS1Comment"># . clear-stream(_test-stream)</span> -<span id="L204" class="LineNr">204 </span> <span class="subxS2Comment"># . . push args</span> -<span id="L205" class="LineNr">205 </span> 68/push _test-stream/imm32 -<span id="L206" class="LineNr">206 </span> <span class="subxS2Comment"># . . call</span> -<span id="L207" class="LineNr">207 </span> e8/call clear-stream/disp32 -<span id="L208" class="LineNr">208 </span> <span class="subxS2Comment"># . . discard args</span> -<span id="L209" class="LineNr">209 </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> 4/imm32 <span class="subxComment"># add to ESP</span> -<span id="L210" class="LineNr">210 </span> <span class="subxS1Comment"># . clear-stream(_test-buffered-file+4)</span> -<span id="L211" class="LineNr">211 </span> <span class="subxS2Comment"># . . push args</span> -<span id="L212" class="LineNr">212 </span> b8/copy-to-EAX _test-buffered-file/imm32 -<span id="L213" class="LineNr">213 </span> 05/add-to-EAX 4/imm32 -<span id="L214" class="LineNr">214 </span> 50/push-EAX -<span id="L215" class="LineNr">215 </span> <span class="subxS2Comment"># . . call</span> -<span id="L216" class="LineNr">216 </span> e8/call clear-stream/disp32 -<span id="L217" class="LineNr">217 </span> <span class="subxS2Comment"># . . discard args</span> -<span id="L218" class="LineNr">218 </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> 4/imm32 <span class="subxComment"># add to ESP</span> -<span id="L219" class="LineNr">219 </span> <span class="subxComment"># read-byte(_test-buffered-file)</span> -<span id="L220" class="LineNr">220 </span> <span class="subxS2Comment"># . . push args</span> -<span id="L221" class="LineNr">221 </span> 68/push _test-buffered-file/imm32 -<span id="L222" class="LineNr">222 </span> <span class="subxS2Comment"># . . call</span> -<span id="L223" class="LineNr">223 </span> e8/call read-byte/disp32 -<span id="L224" class="LineNr">224 </span> <span class="subxS2Comment"># . . discard args</span> -<span id="L225" class="LineNr">225 </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> 4/imm32 <span class="subxComment"># add to ESP</span> -<span id="L226" class="LineNr">226 </span> <span class="subxComment"># check-ints-equal(EAX, -1, msg)</span> -<span id="L227" class="LineNr">227 </span> <span class="subxS2Comment"># . . push args</span> -<span id="L228" class="LineNr">228 </span> 68/push <span class="Constant">"F - test-read-byte-end-of-file"</span>/imm32 -<span id="L229" class="LineNr">229 </span> 68/push -1/imm32 -<span id="L230" class="LineNr">230 </span> 50/push-EAX -<span id="L231" class="LineNr">231 </span> <span class="subxS2Comment"># . . call</span> -<span id="L232" class="LineNr">232 </span> e8/call check-ints-equal/disp32 -<span id="L233" class="LineNr">233 </span> <span class="subxS2Comment"># . . discard args</span> -<span id="L234" class="LineNr">234 </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="L235" class="LineNr">235 </span> <span class="subxS1Comment"># . end</span> -<span id="L236" class="LineNr">236 </span> c3/return -<span id="L237" class="LineNr">237 </span> -<span id="L238" class="LineNr">238 </span>== data -<span id="L239" class="LineNr">239 </span> -<span id="L240" class="LineNr">240 </span><span class="subxMinorFunction">_test-buffered-file</span>: -<span id="L241" class="LineNr">241 </span> <span class="subxComment"># file descriptor or (address stream)</span> -<span id="L242" class="LineNr">242 </span> _test-stream/imm32 -<span id="L243" class="LineNr">243 </span> <span class="subxComment"># current write index</span> -<span id="L244" class="LineNr">244 </span> 00 00 00 00 -<span id="L245" class="LineNr">245 </span> <span class="subxComment"># current read index</span> -<span id="L246" class="LineNr">246 </span> 00 00 00 00 -<span id="L247" class="LineNr">247 </span> <span class="subxComment"># length (8)</span> -<span id="L248" class="LineNr">248 </span> 08 00 00 00 -<span id="L249" class="LineNr">249 </span> <span class="subxComment"># data</span> -<span id="L250" class="LineNr">250 </span> 00 00 00 00 00 00 00 00 <span class="subxComment"># 8 bytes</span> -<span id="L251" class="LineNr">251 </span> -<span id="L252" class="LineNr">252 </span><span class="subxS2Comment"># . . vim:nowrap:textwidth=0</span> +<span id="L27" class="LineNr"> 27 </span><span class="subxComment"># TODO: 8 bytes is too small. We'll need to grow the buffer for efficiency. But</span> +<span id="L28" class="LineNr"> 28 </span><span class="subxComment"># I don't want to type 1024 bytes here.</span> +<span id="L29" class="LineNr"> 29 </span> +<span id="L30" class="LineNr"> 30 </span>== code +<span id="L31" class="LineNr"> 31 </span><span class="subxComment"># instruction effective address register displacement immediate</span> +<span id="L32" class="LineNr"> 32 </span><span class="subxS1Comment"># . op subop mod rm32 base index scale r32</span> +<span id="L33" class="LineNr"> 33 </span><span class="subxS1Comment"># . 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</span> +<span id="L34" class="LineNr"> 34 </span> +<span id="L35" class="LineNr"> 35 </span><span class="subxComment"># main:</span> +<span id="L36" class="LineNr"> 36 </span> e8/call run-tests/disp32 <span class="subxComment"># 'run-tests' is a function created automatically by SubX. It calls all functions that start with 'test-'.</span> +<span id="L37" class="LineNr"> 37 </span><span class="CommentedCode">#? e8/call test-read-byte-multiple/disp32</span> +<span id="L38" class="LineNr"> 38 </span> <span class="subxComment"># syscall(exit, Num-test-failures)</span> +<span id="L39" class="LineNr"> 39 </span> 8b/copy 0/mod/indirect 5/rm32/.disp32 <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> 3/r32/EBX <span class="SpecialChar">Num-test-failures</span>/disp32 <span class="subxComment"># copy *Num-test-failures to EBX</span> +<span id="L40" class="LineNr"> 40 </span> b8/copy-to-EAX 1/imm32 +<span id="L41" class="LineNr"> 41 </span> cd/syscall 0x80/imm8 +<span id="L42" class="LineNr"> 42 </span> +<span id="L43" class="LineNr"> 43 </span><span class="subxComment"># return next byte value in EAX, with top 3 bytes cleared.</span> +<span id="L44" class="LineNr"> 44 </span><span class="subxComment"># On EOF, return 0xffffffff.</span> +<span id="L45" class="LineNr"> 45 </span><span class="subxFunction">read-byte</span>: <span class="subxComment"># f : (address buffered-file) -> byte-or-eof/EAX</span> +<span id="L46" class="LineNr"> 46 </span> <span class="subxS1Comment"># . prolog</span> +<span id="L47" class="LineNr"> 47 </span> 55/push-EBP +<span id="L48" class="LineNr"> 48 </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="L49" class="LineNr"> 49 </span> <span class="subxS1Comment"># . save registers</span> +<span id="L50" class="LineNr"> 50 </span> 51/push-ECX +<span id="L51" class="LineNr"> 51 </span> 56/push-ESI +<span id="L52" class="LineNr"> 52 </span> <span class="subxComment"># ESI = f</span> +<span id="L53" class="LineNr"> 53 </span> 8b/copy 1/mod/*+disp8 4/rm32/sib 5/base/EBP 4/index/none <span class="CommentedCode"> . </span> 6/r32/ESI 8/disp8 <span class="CommentedCode"> . </span> <span class="subxComment"># copy *(EBP+8) to ESI</span> +<span id="L54" class="LineNr"> 54 </span> <span class="subxComment"># ECX = f->read</span> +<span id="L55" class="LineNr"> 55 </span> 8b/copy 1/mod/*+disp8 6/rm32/ESI <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> 1/r32/ECX 8/disp8 <span class="CommentedCode"> . </span> <span class="subxComment"># copy *(ESI+8) to ECX</span> +<span id="L56" class="LineNr"> 56 </span> <span class="subxComment"># if (f->read < f->write) read byte from stream</span> +<span id="L57" class="LineNr"> 57 </span> 3b/compare 1/mod/*+disp8 6/rm32/ESI <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> 1/r32/ECX 4/disp8 <span class="CommentedCode"> . </span> <span class="subxComment"># compare ECX with *(ESI+4)</span> +<span id="L58" class="LineNr"> 58 </span> 7c/jump-if-lesser $read-byte:from-stream/disp8 +<span id="L59" class="LineNr"> 59 </span> <span class="subxComment"># otherwise first populate stream from file</span> +<span id="L60" class="LineNr"> 60 </span> <span class="subxS1Comment"># . clear-stream(stream = f+4)</span> +<span id="L61" class="LineNr"> 61 </span> <span class="subxS2Comment"># . . push args</span> +<span id="L62" class="LineNr"> 62 </span> 8d/copy-address 1/mod/*+disp8 6/rm32/ESI <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> 0/r32/EAX 4/disp8 <span class="CommentedCode"> . </span> <span class="subxComment"># copy ESI+4 to EAX</span> +<span id="L63" class="LineNr"> 63 </span> 50/push-EAX +<span id="L64" class="LineNr"> 64 </span> <span class="subxS2Comment"># . . call</span> +<span id="L65" class="LineNr"> 65 </span> e8/call clear-stream/disp32 +<span id="L66" class="LineNr"> 66 </span> <span class="subxS2Comment"># . . discard args</span> +<span id="L67" class="LineNr"> 67 </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> 4/imm32 <span class="subxComment"># add to ESP</span> +<span id="L68" class="LineNr"> 68 </span> <span class="subxS1Comment"># . EAX = read(f->fd, stream = f+4)</span> +<span id="L69" class="LineNr"> 69 </span> <span class="subxS2Comment"># . . push args</span> +<span id="L70" class="LineNr"> 70 </span> 50/push-EAX +<span id="L71" class="LineNr"> 71 </span> ff 6/subop/push 0/mod/indirect 6/rm32/ESI <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="subxComment"># push *ESI</span> +<span id="L72" class="LineNr"> 72 </span> <span class="subxS2Comment"># . . call</span> +<span id="L73" class="LineNr"> 73 </span> e8/call read/disp32 +<span id="L74" class="LineNr"> 74 </span> <span class="subxS2Comment"># . . discard args</span> +<span id="L75" class="LineNr"> 75 </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="L76" class="LineNr"> 76 </span> <span class="subxComment"># if EAX = 0 return 0xffffffff</span> +<span id="L77" class="LineNr"> 77 </span> 81 7/subop/compare 3/mod/direct 0/rm32/EAX <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> 0/imm32 <span class="subxComment"># compare EAX</span> +<span id="L78" class="LineNr"> 78 </span> 75/jump-if-not-equal $read-byte:from-stream/disp8 +<span id="L79" class="LineNr"> 79 </span> b8/copy-to-EAX 0xffffffff/imm32 +<span id="L80" class="LineNr"> 80 </span> eb/jump $read-byte:end/disp8 +<span id="L81" class="LineNr"> 81 </span><span class="Constant">$read-byte:from-stream</span>: +<span id="L82" class="LineNr"> 82 </span> <span class="subxComment"># reading from stream</span> +<span id="L83" class="LineNr"> 83 </span> <span class="subxComment"># AL = f->data[f->read]</span> +<span id="L84" class="LineNr"> 84 </span> 31/xor 3/mod/direct 0/rm32/EAX <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"># clear EAX</span> +<span id="L85" class="LineNr"> 85 </span> 8a/copy-byte 1/mod/*+disp8 4/rm32/sib 6/base/ESI 1/index/ECX <span class="CommentedCode"> . </span> 0/r32/AL 0x10/disp8 <span class="CommentedCode"> . </span> <span class="subxComment"># copy *(ESI+ECX+16) to AL</span> +<span id="L86" class="LineNr"> 86 </span> <span class="subxComment"># ++f->read</span> +<span id="L87" class="LineNr"> 87 </span> ff 0/subop/increment 1/mod/*+disp8 6/rm32/ESI <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> <span class="CommentedCode"> . </span> 8/disp8 <span class="CommentedCode"> . </span> <span class="subxComment"># increment *(ESI+8)</span> +<span id="L88" class="LineNr"> 88 </span><span class="Constant">$read-byte:end</span>: +<span id="L89" class="LineNr"> 89 </span> <span class="subxS1Comment"># . restore registers</span> +<span id="L90" class="LineNr"> 90 </span> 5e/pop-to-ESI +<span id="L91" class="LineNr"> 91 </span> 59/pop-to-ECX +<span id="L92" class="LineNr"> 92 </span> <span class="subxS1Comment"># . epilog</span> +<span id="L93" class="LineNr"> 93 </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> +<span id="L94" class="LineNr"> 94 </span> 5d/pop-to-EBP +<span id="L95" class="LineNr"> 95 </span> c3/return +<span id="L96" class="LineNr"> 96 </span> +<span id="L97" class="LineNr"> 97 </span><span class="subxComment"># todo: how should write-byte look? What should it do when the output has no</span> +<span id="L98" class="LineNr"> 98 </span><span class="subxComment"># space remaining? Maybe return an error code.</span> +<span id="L99" class="LineNr"> 99 </span> +<span id="L100" class="LineNr">100 </span><span class="subxH1Comment"># - tests</span> +<span id="L101" class="LineNr">101 </span> +<span id="L102" class="LineNr">102 </span><span class="subxTest">test-read-byte-single</span>: +<span id="L103" class="LineNr">103 </span> <span class="subxH1Comment"># - check that read-byte returns first byte of 'file'</span> +<span id="L104" class="LineNr">104 </span> <span class="subxComment"># setup</span> +<span id="L105" class="LineNr">105 </span> <span class="subxS1Comment"># . clear-stream(_test-stream)</span> +<span id="L106" class="LineNr">106 </span> <span class="subxS2Comment"># . . push args</span> +<span id="L107" class="LineNr">107 </span> 68/push _test-stream/imm32 +<span id="L108" class="LineNr">108 </span> <span class="subxS2Comment"># . . call</span> +<span id="L109" class="LineNr">109 </span> e8/call clear-stream/disp32 +<span id="L110" class="LineNr">110 </span> <span class="subxS2Comment"># . . discard args</span> +<span id="L111" class="LineNr">111 </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> 4/imm32 <span class="subxComment"># add to ESP</span> +<span id="L112" class="LineNr">112 </span> <span class="subxS1Comment"># . clear-stream(_test-buffered-file+4)</span> +<span id="L113" class="LineNr">113 </span> <span class="subxS2Comment"># . . push args</span> +<span id="L114" class="LineNr">114 </span> b8/copy-to-EAX _test-buffered-file/imm32 +<span id="L115" class="LineNr">115 </span> 05/add-to-EAX 4/imm32 +<span id="L116" class="LineNr">116 </span> 50/push-EAX +<span id="L117" class="LineNr">117 </span> <span class="subxS2Comment"># . . call</span> +<span id="L118" class="LineNr">118 </span> e8/call clear-stream/disp32 +<span id="L119" class="LineNr">119 </span> <span class="subxS2Comment"># . . discard args</span> +<span id="L120" class="LineNr">120 </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> 4/imm32 <span class="subxComment"># add to ESP</span> +<span id="L121" class="LineNr">121 </span> <span class="subxS1Comment"># . write(_test-stream, "Ab")</span> +<span id="L122" class="LineNr">122 </span> <span class="subxS2Comment"># . . push args</span> +<span id="L123" class="LineNr">123 </span> 68/push <span class="Constant">"Ab"</span>/imm32 +<span id="L124" class="LineNr">124 </span> 68/push _test-stream/imm32 +<span id="L125" class="LineNr">125 </span> <span class="subxS2Comment"># . . call</span> +<span id="L126" class="LineNr">126 </span> e8/call write/disp32 +<span id="L127" class="LineNr">127 </span> <span class="subxS2Comment"># . . discard args</span> +<span id="L128" class="LineNr">128 </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="L129" class="LineNr">129 </span> <span class="subxComment"># read-byte(_test-buffered-file)</span> +<span id="L130" class="LineNr">130 </span> <span class="subxS2Comment"># . . push args</span> +<span id="L131" class="LineNr">131 </span> 68/push _test-buffered-file/imm32 +<span id="L132" class="LineNr">132 </span> <span class="subxS2Comment"># . . call</span> +<span id="L133" class="LineNr">133 </span> e8/call read-byte/disp32 +<span id="L134" class="LineNr">134 </span> <span class="subxS2Comment"># . . discard args</span> +<span id="L135" class="LineNr">135 </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> 4/imm32 <span class="subxComment"># add to ESP</span> +<span id="L136" class="LineNr">136 </span> <span class="subxComment"># check-ints-equal(EAX, 'A', msg)</span> +<span id="L137" class="LineNr">137 </span> <span class="subxS2Comment"># . . push args</span> +<span id="L138" class="LineNr">138 </span> 68/push <span class="Constant">"F - test-read-byte-single"</span>/imm32 +<span id="L139" class="LineNr">139 </span> 68/push 0x41/imm32 +<span id="L140" class="LineNr">140 </span> 50/push-EAX +<span id="L141" class="LineNr">141 </span> <span class="subxS2Comment"># . . call</span> +<span id="L142" class="LineNr">142 </span> e8/call check-ints-equal/disp32 +<span id="L143" class="LineNr">143 </span> <span class="subxS2Comment"># . . discard args</span> +<span id="L144" class="LineNr">144 </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="L145" class="LineNr">145 </span> <span class="subxS1Comment"># . end</span> +<span id="L146" class="LineNr">146 </span> c3/return +<span id="L147" class="LineNr">147 </span> +<span id="L148" class="LineNr">148 </span><span class="subxTest">test-read-byte-multiple</span>: +<span id="L149" class="LineNr">149 </span> <span class="subxH1Comment"># - call read-byte twice, check that second call returns second byte</span> +<span id="L150" class="LineNr">150 </span> <span class="subxComment"># setup</span> +<span id="L151" class="LineNr">151 </span> <span class="subxS1Comment"># . clear-stream(_test-stream)</span> +<span id="L152" class="LineNr">152 </span> <span class="subxS2Comment"># . . push args</span> +<span id="L153" class="LineNr">153 </span> 68/push _test-stream/imm32 +<span id="L154" class="LineNr">154 </span> <span class="subxS2Comment"># . . call</span> +<span id="L155" class="LineNr">155 </span> e8/call clear-stream/disp32 +<span id="L156" class="LineNr">156 </span> <span class="subxS2Comment"># . . discard args</span> +<span id="L157" class="LineNr">157 </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> 4/imm32 <span class="subxComment"># add to ESP</span> +<span id="L158" class="LineNr">158 </span> <span class="subxS1Comment"># . clear-stream(_test-buffered-file+4)</span> +<span id="L159" class="LineNr">159 </span> <span class="subxS2Comment"># . . push args</span> +<span id="L160" class="LineNr">160 </span> b8/copy-to-EAX _test-buffered-file/imm32 +<span id="L161" class="LineNr">161 </span> 05/add-to-EAX 4/imm32 +<span id="L162" class="LineNr">162 </span> 50/push-EAX +<span id="L163" class="LineNr">163 </span> <span class="subxS2Comment"># . . call</span> +<span id="L164" class="LineNr">164 </span> e8/call clear-stream/disp32 +<span id="L165" class="LineNr">165 </span> <span class="subxS2Comment"># . . discard args</span> +<span id="L166" class="LineNr">166 </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> 4/imm32 <span class="subxComment"># add to ESP</span> +<span id="L167" class="LineNr">167 </span> <span class="subxS1Comment"># . write(_test-stream, "Ab")</span> +<span id="L168" class="LineNr">168 </span> <span class="subxS2Comment"># . . push args</span> +<span id="L169" class="LineNr">169 </span> 68/push <span class="Constant">"Ab"</span>/imm32 +<span id="L170" class="LineNr">170 </span> 68/push _test-stream/imm32 +<span id="L171" class="LineNr">171 </span> <span class="subxS2Comment"># . . call</span> +<span id="L172" class="LineNr">172 </span> e8/call write/disp32 +<span id="L173" class="LineNr">173 </span> <span class="subxS2Comment"># . . discard args</span> +<span id="L174" class="LineNr">174 </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="L175" class="LineNr">175 </span> <span class="subxComment"># read-byte(_test-buffered-file)</span> +<span id="L176" class="LineNr">176 </span> <span class="subxS2Comment"># . . push args</span> +<span id="L177" class="LineNr">177 </span> 68/push _test-buffered-file/imm32 +<span id="L178" class="LineNr">178 </span> <span class="subxS2Comment"># . . call</span> +<span id="L179" class="LineNr">179 </span> e8/call read-byte/disp32 +<span id="L180" class="LineNr">180 </span> <span class="subxS2Comment"># . . discard args</span> +<span id="L181" class="LineNr">181 </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> 4/imm32 <span class="subxComment"># add to ESP</span> +<span id="L182" class="LineNr">182 </span> <span class="subxComment"># read-byte(_test-buffered-file)</span> +<span id="L183" class="LineNr">183 </span> <span class="subxS2Comment"># . . push args</span> +<span id="L184" class="LineNr">184 </span> 68/push _test-buffered-file/imm32 +<span id="L185" class="LineNr">185 </span> <span class="subxS2Comment"># . . call</span> +<span id="L186" class="LineNr">186 </span> e8/call read-byte/disp32 +<span id="L187" class="LineNr">187 </span> <span class="subxS2Comment"># . . discard args</span> +<span id="L188" class="LineNr">188 </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> 4/imm32 <span class="subxComment"># add to ESP</span> +<span id="L189" class="LineNr">189 </span> <span class="subxComment"># check-ints-equal(EAX, 'b', msg)</span> +<span id="L190" class="LineNr">190 </span> <span class="subxS2Comment"># . . push args</span> +<span id="L191" class="LineNr">191 </span> 68/push <span class="Constant">"F - test-read-byte-multiple"</span>/imm32 +<span id="L192" class="LineNr">192 </span> 68/push 0x62/imm32 +<span id="L193" class="LineNr">193 </span> 50/push-EAX +<span id="L194" class="LineNr">194 </span> <span class="subxS2Comment"># . . call</span> +<span id="L195" class="LineNr">195 </span> e8/call check-ints-equal/disp32 +<span id="L196" class="LineNr">196 </span> <span class="subxS2Comment"># . . discard args</span> +<span id="L197" class="LineNr">197 </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="L198" class="LineNr">198 </span> <span class="subxS1Comment"># . end</span> +<span id="L199" class="LineNr">199 </span> c3/return +<span id="L200" class="LineNr">200 </span> +<span id="L201" class="LineNr">201 </span><span class="subxTest">test-read-byte-end-of-file</span>: +<span id="L202" class="LineNr">202 </span> <span class="subxH1Comment"># - call read-byte on an empty 'file', check that it returns -1</span> +<span id="L203" class="LineNr">203 </span> <span class="subxComment"># setup</span> +<span id="L204" class="LineNr">204 </span> <span class="subxS1Comment"># . clear-stream(_test-stream)</span> +<span id="L205" class="LineNr">205 </span> <span class="subxS2Comment"># . . push args</span> +<span id="L206" class="LineNr">206 </span> 68/push _test-stream/imm32 +<span id="L207" class="LineNr">207 </span> <span class="subxS2Comment"># . . call</span> +<span id="L208" class="LineNr">208 </span> e8/call clear-stream/disp32 +<span id="L209" class="LineNr">209 </span> <span class="subxS2Comment"># . . discard args</span> +<span id="L210" class="LineNr">210 </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> 4/imm32 <span class="subxComment"># add to ESP</span> +<span id="L211" class="LineNr">211 </span> <span class="subxS1Comment"># . clear-stream(_test-buffered-file+4)</span> +<span id="L212" class="LineNr">212 </span> <span class="subxS2Comment"># . . push args</span> +<span id="L213" class="LineNr">213 </span> b8/copy-to-EAX _test-buffered-file/imm32 +<span id="L214" class="LineNr">214 </span> 05/add-to-EAX 4/imm32 +<span id="L215" class="LineNr">215 </span> 50/push-EAX +<span id="L216" class="LineNr">216 </span> <span class="subxS2Comment"># . . call</span> +<span id="L217" class="LineNr">217 </span> e8/call clear-stream/disp32 +<span id="L218" class="LineNr">218 </span> <span class="subxS2Comment"># . . discard args</span> +<span id="L219" class="LineNr">219 </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> 4/imm32 <span class="subxComment"># add to ESP</span> +<span id="L220" class="LineNr">220 </span> <span class="subxComment"># read-byte(_test-buffered-file)</span> +<span id="L221" class="LineNr">221 </span> <span class="subxS2Comment"># . . push args</span> +<span id="L222" class="LineNr">222 </span> 68/push _test-buffered-file/imm32 +<span id="L223" class="LineNr">223 </span> <span class="subxS2Comment"># . . call</span> +<span id="L224" class="LineNr">224 </span> e8/call read-byte/disp32 +<span id="L225" class="LineNr">225 </span> <span class="subxS2Comment"># . . discard args</span> +<span id="L226" class="LineNr">226 </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> 4/imm32 <span class="subxComment"># add to ESP</span> +<span id="L227" class="LineNr">227 </span> <span class="subxComment"># check-ints-equal(EAX, -1, msg)</span> +<span id="L228" class="LineNr">228 </span> <span class="subxS2Comment"># . . push args</span> +<span id="L229" class="LineNr">229 </span> 68/push <span class="Constant">"F - test-read-byte-end-of-file"</span>/imm32 +<span id="L230" class="LineNr">230 </span> 68/push -1/imm32 +<span id="L231" class="LineNr">231 </span> 50/push-EAX +<span id="L232" class="LineNr">232 </span> <span class="subxS2Comment"># . . call</span> +<span id="L233" class="LineNr">233 </span> e8/call check-ints-equal/disp32 +<span id="L234" class="LineNr">234 </span> <span class="subxS2Comment"># . . discard args</span> +<span id="L235" class="LineNr">235 </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="L236" class="LineNr">236 </span> <span class="subxS1Comment"># . end</span> +<span id="L237" class="LineNr">237 </span> c3/return +<span id="L238" class="LineNr">238 </span> +<span id="L239" class="LineNr">239 </span>== data +<span id="L240" class="LineNr">240 </span> +<span id="L241" class="LineNr">241 </span><span class="subxMinorFunction">_test-buffered-file</span>: +<span id="L242" class="LineNr">242 </span> <span class="subxComment"># file descriptor or (address stream)</span> +<span id="L243" class="LineNr">243 </span> _test-stream/imm32 +<span id="L244" class="LineNr">244 </span> <span class="subxComment"># current write index</span> +<span id="L245" class="LineNr">245 </span> 00 00 00 00 +<span id="L246" class="LineNr">246 </span> <span class="subxComment"># current read index</span> +<span id="L247" class="LineNr">247 </span> 00 00 00 00 +<span id="L248" class="LineNr">248 </span> <span class="subxComment"># length (8)</span> +<span id="L249" class="LineNr">249 </span> 08 00 00 00 +<span id="L250" class="LineNr">250 </span> <span class="subxComment"># data</span> +<span id="L251" class="LineNr">251 </span> 00 00 00 00 00 00 00 00 <span class="subxComment"># 8 bytes</span> +<span id="L252" class="LineNr">252 </span> +<span id="L253" class="LineNr">253 </span><span class="subxS2Comment"># . . vim:nowrap:textwidth=0</span> </pre> </body> </html> diff --git a/subx/059read-byte.subx b/subx/059read-byte.subx index 7dd9658e..07958a63 100644 --- a/subx/059read-byte.subx +++ b/subx/059read-byte.subx @@ -24,7 +24,8 @@ Stdin: # 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. +# TODO: 8 bytes is too small. We'll need to grow the buffer for efficiency. But +# I don't want to type 1024 bytes here. == code # instruction effective address register displacement immediate @@ -93,9 +94,6 @@ $read-byte:end: 5d/pop-to-EBP c3/return -# todo: how should write-byte look? What should it do when the output has no -# space remaining? Maybe return an error code. - # - tests test-read-byte-single: |