216 lines
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216 lines
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<title>C Strings</title>
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<h1><a href="../index.html">
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</a></h1>
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<ul><li><a href="../inweb/index.html">inweb</a></li>
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</ul><h2>Foundation Module</h2><ul>
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<li><a href="../foundation-test/index.html">foundation-test</a></li>
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<!--Weave of 'C Strings' generated by Inweb-->
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<div class="breadcrumbs">
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<ul class="crumbs"><li><a href="../index.html">Home</a></li><li><a href="index.html">foundation</a></li><li><a href="index.html#4">Chapter 4: Text Handling</a></li><li><b>C Strings</b></li></ul></div>
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<p class="purpose">A minimal library for handling C-style strings.</p>
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<ul class="toc"><li><a href="4-cst.html#SP10">§10. Text storage</a></li></ul><hr class="tocbar">
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<p class="commentary firstcommentary"><a id="SP1"></a><b>§1. </b>Programs using Foundation store text in <span class="extract"><span class="extract-syntax">text_stream</span></span> structures almost all
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of the time, but old-style, null-terminated <span class="extract"><span class="extract-syntax">char *</span></span> array strings are
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still occasionally needed.
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</p>
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<p class="commentary">We need to handle C strings long enough to contain any plausible filename, and
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any run of a dozen or so lines of code; but we have no real need to handle
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strings of unlimited length, nor to be parsimonious with memory.
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</p>
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<p class="commentary">The following defines a type for a string long enough for our purposes.
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It should be at least as long as the constant sometimes called <span class="extract"><span class="extract-syntax">PATH_MAX</span></span>,
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the maximum length of a pathname, which is 1024 on Mac OS X.
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</p>
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<pre class="definitions code-font"><span class="definition-keyword">define</span> <span class="constant-syntax">MAX_STRING_LENGTH</span><span class="plain-syntax"> </span><span class="constant-syntax">8</span><span class="plain-syntax">*1024</span>
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</pre>
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<pre class="displayed-code all-displayed-code code-font">
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<span class="reserved-syntax">typedef</span><span class="plain-syntax"> </span><span class="reserved-syntax">char</span><span class="plain-syntax"> </span><span class="identifier-syntax">string</span><span class="plain-syntax">[</span><span class="constant-syntax">MAX_STRING_LENGTH</span><span class="plain-syntax">+1];</span>
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</pre>
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<p class="commentary firstcommentary"><a id="SP2"></a><b>§2. </b>Occasionally we need access to the real, unbounded strlen:
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</p>
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<pre class="displayed-code all-displayed-code code-font">
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<span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="function-syntax">CStrings::strlen_unbounded</span><button class="popup" onclick="togglePopup('usagePopup1')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup1">Usage of <span class="code-font"><span class="function-syntax">CStrings::strlen_unbounded</span></span>:<br/><a href="4-cst.html#SP11">§11</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">const</span><span class="plain-syntax"> </span><span class="reserved-syntax">char</span><span class="plain-syntax"> *</span><span class="identifier-syntax">p</span><span class="plain-syntax">) {</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">return</span><span class="plain-syntax"> (</span><span class="reserved-syntax">int</span><span class="plain-syntax">) </span><span class="identifier-syntax">strlen</span><span class="plain-syntax">(</span><span class="identifier-syntax">p</span><span class="plain-syntax">);</span>
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<span class="plain-syntax">}</span>
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</pre>
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<p class="commentary firstcommentary"><a id="SP3"></a><b>§3. </b>Any out-of-range access immediately halts the program; this is drastic, but
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an attempt to continue execution after a string overflow might conceivably
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result in a malformatted shell command being passed to the operating system,
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which we cannot risk.
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</p>
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<pre class="displayed-code all-displayed-code code-font">
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<span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="function-syntax">CStrings::check_len</span><button class="popup" onclick="togglePopup('usagePopup2')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup2">Usage of <span class="code-font"><span class="function-syntax">CStrings::check_len</span></span>:<br/><a href="4-cst.html#SP5">§5</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">n</span><span class="plain-syntax">) {</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> ((</span><span class="identifier-syntax">n</span><span class="plain-syntax"> > </span><span class="constant-syntax">MAX_STRING_LENGTH</span><span class="plain-syntax">) || (</span><span class="identifier-syntax">n</span><span class="plain-syntax"> < </span><span class="constant-syntax">0</span><span class="plain-syntax">)) </span><a href="3-em.html#SP2" class="function-link"><span class="function-syntax">Errors::fatal</span></a><span class="plain-syntax">(</span><span class="string-syntax">"String overflow\n"</span><span class="plain-syntax">);</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">n</span><span class="plain-syntax">;</span>
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<span class="plain-syntax">}</span>
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</pre>
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<p class="commentary firstcommentary"><a id="SP4"></a><b>§4. </b>The following is then protected from reading out of range if given a
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non-terminated string, though this should never actually happen.
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</p>
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<pre class="displayed-code all-displayed-code code-font">
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<span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="function-syntax">CStrings::len</span><button class="popup" onclick="togglePopup('usagePopup3')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup3">Usage of <span class="code-font"><span class="function-syntax">CStrings::len</span></span>:<br/><a href="4-cst.html#SP5">§5</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">char</span><span class="plain-syntax"> *</span><span class="identifier-syntax">str</span><span class="plain-syntax">) {</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">for</span><span class="plain-syntax"> (</span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">i</span><span class="plain-syntax">=0; </span><span class="identifier-syntax">i</span><span class="plain-syntax"><=</span><span class="constant-syntax">MAX_STRING_LENGTH</span><span class="plain-syntax">; </span><span class="identifier-syntax">i</span><span class="plain-syntax">++)</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">str</span><span class="plain-syntax">[</span><span class="identifier-syntax">i</span><span class="plain-syntax">] == </span><span class="constant-syntax">0</span><span class="plain-syntax">) </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">i</span><span class="plain-syntax">;</span>
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<span class="plain-syntax"> </span><span class="identifier-syntax">str</span><span class="plain-syntax">[</span><span class="constant-syntax">MAX_STRING_LENGTH</span><span class="plain-syntax">] = </span><span class="constant-syntax">0</span><span class="plain-syntax">;</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="constant-syntax">MAX_STRING_LENGTH</span><span class="plain-syntax">;</span>
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<span class="plain-syntax">}</span>
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</pre>
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<p class="commentary firstcommentary"><a id="SP5"></a><b>§5. </b>We then have a replacement for <span class="extract"><span class="extract-syntax">strcpy</span></span>, identical except that it's
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bounds-checked:
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</p>
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<pre class="displayed-code all-displayed-code code-font">
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<span class="reserved-syntax">void</span><span class="plain-syntax"> </span><span class="function-syntax">CStrings::copy</span><span class="plain-syntax">(</span><span class="reserved-syntax">char</span><span class="plain-syntax"> *</span><span class="identifier-syntax">to</span><span class="plain-syntax">, </span><span class="reserved-syntax">char</span><span class="plain-syntax"> *</span><span class="identifier-syntax">from</span><span class="plain-syntax">) {</span>
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<span class="plain-syntax"> </span><a href="4-cst.html#SP3" class="function-link"><span class="function-syntax">CStrings::check_len</span></a><span class="plain-syntax">(</span><a href="4-cst.html#SP4" class="function-link"><span class="function-syntax">CStrings::len</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">from</span><span class="plain-syntax">));</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">i</span><span class="plain-syntax">;</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">for</span><span class="plain-syntax"> (</span><span class="identifier-syntax">i</span><span class="plain-syntax">=0; ((</span><span class="identifier-syntax">from</span><span class="plain-syntax">[</span><span class="identifier-syntax">i</span><span class="plain-syntax">]) && (</span><span class="identifier-syntax">i</span><span class="plain-syntax"> < </span><span class="constant-syntax">MAX_STRING_LENGTH</span><span class="plain-syntax">)); </span><span class="identifier-syntax">i</span><span class="plain-syntax">++) </span><span class="identifier-syntax">to</span><span class="plain-syntax">[</span><span class="identifier-syntax">i</span><span class="plain-syntax">] = </span><span class="identifier-syntax">from</span><span class="plain-syntax">[</span><span class="identifier-syntax">i</span><span class="plain-syntax">];</span>
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<span class="plain-syntax"> </span><span class="identifier-syntax">to</span><span class="plain-syntax">[</span><span class="identifier-syntax">i</span><span class="plain-syntax">] = </span><span class="constant-syntax">0</span><span class="plain-syntax">;</span>
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<span class="plain-syntax">}</span>
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</pre>
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<p class="commentary firstcommentary"><a id="SP6"></a><b>§6. </b>String comparisons will be done with the following, not <span class="extract"><span class="extract-syntax">strcmp</span></span> directly:
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</p>
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<pre class="displayed-code all-displayed-code code-font">
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<span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="function-syntax">CStrings::ne</span><span class="plain-syntax">(</span><span class="reserved-syntax">char</span><span class="plain-syntax"> *</span><span class="identifier-syntax">A</span><span class="plain-syntax">, </span><span class="reserved-syntax">char</span><span class="plain-syntax"> *</span><span class="identifier-syntax">B</span><span class="plain-syntax">) {</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">return</span><span class="plain-syntax"> (</span><a href="4-cst.html#SP7" class="function-link"><span class="function-syntax">CStrings::cmp</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">A</span><span class="plain-syntax">, </span><span class="identifier-syntax">B</span><span class="plain-syntax">) == </span><span class="constant-syntax">0</span><span class="plain-syntax">)?</span><span class="identifier-syntax">FALSE:TRUE</span><span class="plain-syntax">;</span>
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<span class="plain-syntax">}</span>
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</pre>
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<p class="commentary firstcommentary"><a id="SP7"></a><b>§7. </b>On the rare occasions when we need to sort alphabetically we'll also call:
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</p>
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<pre class="displayed-code all-displayed-code code-font">
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<span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="function-syntax">CStrings::cmp</span><button class="popup" onclick="togglePopup('usagePopup4')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup4">Usage of <span class="code-font"><span class="function-syntax">CStrings::cmp</span></span>:<br/><a href="4-cst.html#SP6">§6</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">char</span><span class="plain-syntax"> *</span><span class="identifier-syntax">A</span><span class="plain-syntax">, </span><span class="reserved-syntax">char</span><span class="plain-syntax"> *</span><span class="identifier-syntax">B</span><span class="plain-syntax">) {</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> ((</span><span class="identifier-syntax">A</span><span class="plain-syntax"> == </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">) || (</span><span class="identifier-syntax">A</span><span class="plain-syntax">[0] == </span><span class="constant-syntax">0</span><span class="plain-syntax">)) {</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> ((</span><span class="identifier-syntax">B</span><span class="plain-syntax"> == </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">) || (</span><span class="identifier-syntax">B</span><span class="plain-syntax">[0] == </span><span class="constant-syntax">0</span><span class="plain-syntax">)) </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="constant-syntax">0</span><span class="plain-syntax">;</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">return</span><span class="plain-syntax"> -1;</span>
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<span class="plain-syntax"> }</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> ((</span><span class="identifier-syntax">B</span><span class="plain-syntax"> == </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">) || (</span><span class="identifier-syntax">B</span><span class="plain-syntax">[0] == </span><span class="constant-syntax">0</span><span class="plain-syntax">)) </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="constant-syntax">1</span><span class="plain-syntax">;</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">strcmp</span><span class="plain-syntax">(</span><span class="identifier-syntax">A</span><span class="plain-syntax">, </span><span class="identifier-syntax">B</span><span class="plain-syntax">);</span>
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<span class="plain-syntax">}</span>
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</pre>
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<p class="commentary firstcommentary"><a id="SP8"></a><b>§8. </b>And the following is needed to deal with extension filenames on platforms
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whose locale is encoded as UTF-8.
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</p>
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<pre class="displayed-code all-displayed-code code-font">
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<span class="reserved-syntax">void</span><span class="plain-syntax"> </span><span class="function-syntax">CStrings::transcode_ISO_string_to_UTF8</span><span class="plain-syntax">(</span><span class="reserved-syntax">char</span><span class="plain-syntax"> *</span><span class="identifier-syntax">p</span><span class="plain-syntax">, </span><span class="reserved-syntax">char</span><span class="plain-syntax"> *</span><span class="identifier-syntax">dest</span><span class="plain-syntax">) {</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">i</span><span class="plain-syntax">, </span><span class="identifier-syntax">j</span><span class="plain-syntax">;</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">for</span><span class="plain-syntax"> (</span><span class="identifier-syntax">i</span><span class="plain-syntax">=0, </span><span class="identifier-syntax">j</span><span class="plain-syntax">=0; </span><span class="identifier-syntax">p</span><span class="plain-syntax">[</span><span class="identifier-syntax">i</span><span class="plain-syntax">]; </span><span class="identifier-syntax">i</span><span class="plain-syntax">++) {</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">charcode</span><span class="plain-syntax"> = (</span><span class="reserved-syntax">int</span><span class="plain-syntax">) (((</span><span class="reserved-syntax">unsigned</span><span class="plain-syntax"> </span><span class="reserved-syntax">char</span><span class="plain-syntax"> *)</span><span class="identifier-syntax">p</span><span class="plain-syntax">)[</span><span class="identifier-syntax">i</span><span class="plain-syntax">]);</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">charcode</span><span class="plain-syntax"> >= </span><span class="constant-syntax">128</span><span class="plain-syntax">) {</span>
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<span class="plain-syntax"> </span><span class="identifier-syntax">dest</span><span class="plain-syntax">[</span><span class="identifier-syntax">j</span><span class="plain-syntax">++] = (</span><span class="reserved-syntax">char</span><span class="plain-syntax">) (</span><span class="constant-syntax">0xC0</span><span class="plain-syntax"> + (</span><span class="identifier-syntax">charcode</span><span class="plain-syntax"> >> </span><span class="constant-syntax">6</span><span class="plain-syntax">));</span>
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<span class="plain-syntax"> </span><span class="identifier-syntax">dest</span><span class="plain-syntax">[</span><span class="identifier-syntax">j</span><span class="plain-syntax">++] = (</span><span class="reserved-syntax">char</span><span class="plain-syntax">) (</span><span class="constant-syntax">0x80</span><span class="plain-syntax"> + (</span><span class="identifier-syntax">charcode</span><span class="plain-syntax"> & </span><span class="constant-syntax">0x3f</span><span class="plain-syntax">));</span>
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<span class="plain-syntax"> } </span><span class="reserved-syntax">else</span><span class="plain-syntax"> {</span>
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<span class="plain-syntax"> </span><span class="identifier-syntax">dest</span><span class="plain-syntax">[</span><span class="identifier-syntax">j</span><span class="plain-syntax">++] = </span><span class="identifier-syntax">p</span><span class="plain-syntax">[</span><span class="identifier-syntax">i</span><span class="plain-syntax">];</span>
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<span class="plain-syntax"> }</span>
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<span class="plain-syntax"> }</span>
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<span class="plain-syntax"> </span><span class="identifier-syntax">dest</span><span class="plain-syntax">[</span><span class="identifier-syntax">j</span><span class="plain-syntax">] = </span><span class="constant-syntax">0</span><span class="plain-syntax">;</span>
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<span class="plain-syntax">}</span>
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</pre>
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<p class="commentary firstcommentary"><a id="SP9"></a><b>§9. </b>I dislike to use <span class="extract"><span class="extract-syntax">strncpy</span></span> because, and for some reason this surprises
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me every time, it truncates but fails to write a null termination character
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if the string to be copied is larger than the buffer to write to: the
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result is therefore not a well-formed string and we have to fix matters by
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hand. This I think makes for opaque code. So:
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</p>
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<pre class="displayed-code all-displayed-code code-font">
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<span class="reserved-syntax">void</span><span class="plain-syntax"> </span><span class="function-syntax">CStrings::truncated_strcpy</span><button class="popup" onclick="togglePopup('usagePopup5')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup5">Usage of <span class="code-font"><span class="function-syntax">CStrings::truncated_strcpy</span></span>:<br/>Debugging Log - <a href="2-dl.html#SP6">§6</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">char</span><span class="plain-syntax"> *</span><span class="identifier-syntax">to</span><span class="plain-syntax">, </span><span class="reserved-syntax">char</span><span class="plain-syntax"> *</span><span class="identifier-syntax">from</span><span class="plain-syntax">, </span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">max</span><span class="plain-syntax">) {</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">i</span><span class="plain-syntax">;</span>
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<span class="plain-syntax"> </span><span class="reserved-syntax">for</span><span class="plain-syntax"> (</span><span class="identifier-syntax">i</span><span class="plain-syntax">=0; ((</span><span class="identifier-syntax">from</span><span class="plain-syntax">[</span><span class="identifier-syntax">i</span><span class="plain-syntax">]) && (</span><span class="identifier-syntax">i</span><span class="plain-syntax"><</span><span class="identifier-syntax">max</span><span class="plain-syntax">-1)); </span><span class="identifier-syntax">i</span><span class="plain-syntax">++) </span><span class="identifier-syntax">to</span><span class="plain-syntax">[</span><span class="identifier-syntax">i</span><span class="plain-syntax">] = </span><span class="identifier-syntax">from</span><span class="plain-syntax">[</span><span class="identifier-syntax">i</span><span class="plain-syntax">];</span>
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<span class="plain-syntax"> </span><span class="identifier-syntax">to</span><span class="plain-syntax">[</span><span class="identifier-syntax">i</span><span class="plain-syntax">] = </span><span class="constant-syntax">0</span><span class="plain-syntax">;</span>
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<span class="plain-syntax">}</span>
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</pre>
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<p class="commentary firstcommentary"><a id="SP10"></a><b>§10. Text storage. </b>The following is convenient for parking a read-only string of text somewhere
|
|
safe in memory. Since the length can't be extended, it's usually unsafe
|
|
to write to the result. (Inform tools very seldom use this, because C strings
|
|
are almost always best avoided.)
|
|
</p>
|
|
|
|
<pre class="displayed-code all-displayed-code code-font">
|
|
<span class="reserved-syntax">typedef</span><span class="plain-syntax"> </span><span class="reserved-syntax">struct</span><span class="plain-syntax"> </span><span class="reserved-syntax">string_storage_area</span><span class="plain-syntax"> {</span>
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|
<span class="plain-syntax"> </span><span class="reserved-syntax">char</span><span class="plain-syntax"> *</span><span class="identifier-syntax">storage_at</span><span class="plain-syntax">;</span>
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|
<span class="plain-syntax"> </span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">capacity</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> </span><span class="constant-syntax">CLASS_DEFINITION</span>
|
|
<span class="plain-syntax">} </span><span class="reserved-syntax">string_storage_area</span><span class="plain-syntax">;</span>
|
|
</pre>
|
|
<ul class="endnotetexts"><li>The structure string_storage_area is private to this section.</li></ul>
|
|
<p class="commentary firstcommentary"><a id="SP11"></a><b>§11. </b></p>
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|
|
|
<pre class="displayed-code all-displayed-code code-font">
|
|
<span class="reserved-syntax">char</span><span class="plain-syntax"> *</span><span class="function-syntax">CStrings::park_string</span><span class="plain-syntax">(</span><span class="reserved-syntax">char</span><span class="plain-syntax"> *</span><span class="identifier-syntax">from</span><span class="plain-syntax">) {</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">string_storage_area</span><span class="plain-syntax"> *</span><span class="identifier-syntax">ssa</span><span class="plain-syntax"> = </span><span class="identifier-syntax">CREATE</span><span class="plain-syntax">(</span><span class="reserved-syntax">string_storage_area</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">ssa</span><span class="plain-syntax">-></span><span class="element-syntax">capacity</span><span class="plain-syntax"> = (</span><span class="reserved-syntax">int</span><span class="plain-syntax">) </span><a href="4-cst.html#SP2" class="function-link"><span class="function-syntax">CStrings::strlen_unbounded</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">from</span><span class="plain-syntax">) + </span><span class="constant-syntax">1</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">ssa</span><span class="plain-syntax">-></span><span class="element-syntax">storage_at</span><span class="plain-syntax"> = </span><a href="2-mmr.html#SP24" class="function-link"><span class="function-syntax">Memory::malloc</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">ssa</span><span class="plain-syntax">-></span><span class="element-syntax">capacity</span><span class="plain-syntax">, </span><span class="constant-syntax">STRING_STORAGE_MREASON</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">strcpy</span><span class="plain-syntax">(</span><span class="identifier-syntax">ssa</span><span class="plain-syntax">-></span><span class="element-syntax">storage_at</span><span class="plain-syntax">, </span><span class="identifier-syntax">from</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">ssa</span><span class="plain-syntax">-></span><span class="element-syntax">storage_at</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax">}</span>
|
|
</pre>
|
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<p class="commentary firstcommentary"><a id="SP12"></a><b>§12. </b>And here we free any SSAs needed in the course of the run.
|
|
</p>
|
|
|
|
<pre class="displayed-code all-displayed-code code-font">
|
|
<span class="reserved-syntax">void</span><span class="plain-syntax"> </span><span class="function-syntax">CStrings::free_ssas</span><button class="popup" onclick="togglePopup('usagePopup6')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup6">Usage of <span class="code-font"><span class="function-syntax">CStrings::free_ssas</span></span>:<br/>Memory - <a href="2-mmr.html#SP12">§12</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">void</span><span class="plain-syntax">) {</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">string_storage_area</span><span class="plain-syntax"> *</span><span class="identifier-syntax">ssa</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">LOOP_OVER</span><span class="plain-syntax">(</span><span class="identifier-syntax">ssa</span><span class="plain-syntax">, </span><span class="reserved-syntax">string_storage_area</span><span class="plain-syntax">)</span>
|
|
<span class="plain-syntax"> </span><a href="2-mmr.html#SP26" class="function-link"><span class="function-syntax">Memory::I7_free</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">ssa</span><span class="plain-syntax">-></span><span class="element-syntax">storage_at</span><span class="plain-syntax">, </span><span class="constant-syntax">STRING_STORAGE_MREASON</span><span class="plain-syntax">, </span><span class="identifier-syntax">ssa</span><span class="plain-syntax">-></span><span class="element-syntax">capacity</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax">}</span>
|
|
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