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 <span id="projectnumber">1.4.6</span>
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<div id="projectbrief">commandline package manager</div>
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<li class="navelem"><a class="el" href="dir_18f22d4be2ca84c350e120b6506056ca.xhtml">apt-pkg</a></li><li class="navelem"><a class="el" href="dir_c6ef23f15b074dcedf6810e24f2a7676.xhtml">contrib</a></li> </ul>
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<div class="fragment"><div class="line"><a name="l00001"></a><span class="lineno"> 1</span> <span class="comment">/*</span></div><div class="line"><a name="l00002"></a><span class="lineno"> 2</span> <span class="comment"> * Basic implementation of string_view</span></div><div class="line"><a name="l00003"></a><span class="lineno"> 3</span> <span class="comment"> *</span></div><div class="line"><a name="l00004"></a><span class="lineno"> 4</span> <span class="comment"> * (C) 2015 Julian Andres Klode <jak@debian.org></span></div><div class="line"><a name="l00005"></a><span class="lineno"> 5</span> <span class="comment"> *</span></div><div class="line"><a name="l00006"></a><span class="lineno"> 6</span> <span class="comment"> * This program is free software; you can redistribute it and/or modify</span></div><div class="line"><a name="l00007"></a><span class="lineno"> 7</span> <span class="comment"> * it under the terms of the GNU General Public License as published by</span></div><div class="line"><a name="l00008"></a><span class="lineno"> 8</span> <span class="comment"> * the Free Software Foundation; either version 2 of the License, or</span></div><div class="line"><a name="l00009"></a><span class="lineno"> 9</span> <span class="comment"> * (at your option) any later version.</span></div><div class="line"><a name="l00010"></a><span class="lineno"> 10</span> <span class="comment"> */</span></div><div class="line"><a name="l00011"></a><span class="lineno"> 11</span> </div><div class="line"><a name="l00012"></a><span class="lineno"> 12</span> <span class="preprocessor">#if !defined(APT_STRINGVIEW_H) && defined(APT_PKG_EXPOSE_STRING_VIEW)</span></div><div class="line"><a name="l00013"></a><span class="lineno"> 13</span> <span class="preprocessor">#define APT_STRINGVIEW_H</span></div><div class="line"><a name="l00014"></a><span class="lineno"> 14</span> <span class="preprocessor">#include <string.h></span></div><div class="line"><a name="l00015"></a><span class="lineno"> 15</span> <span class="preprocessor">#include <string></span></div><div class="line"><a name="l00016"></a><span class="lineno"> 16</span> <span class="preprocessor">#include <apt-pkg/macros.h></span></div><div class="line"><a name="l00017"></a><span class="lineno"> 17</span> </div><div class="line"><a name="l00018"></a><span class="lineno"> 18</span> <span class="keyword">namespace </span><a class="code" href="namespaceAPT.xhtml">APT</a> {</div><div class="line"><a name="l00019"></a><span class="lineno"> 19</span> </div><div class="line"><a name="l00027"></a><span class="lineno"> 27</span> <span class="keyword">class </span>APT_HIDDEN StringView {</div><div class="line"><a name="l00028"></a><span class="lineno"> 28</span>  <span class="keyword">const</span> <span class="keywordtype">char</span> *data_;</div><div class="line"><a name="l00029"></a><span class="lineno"> 29</span>  <span class="keywordtype">size_t</span> size_;</div><div class="line"><a name="l00030"></a><span class="lineno"> 30</span> </div><div class="line"><a name="l00031"></a><span class="lineno"> 31</span> <span class="keyword">public</span>:</div><div class="line"><a name="l00032"></a><span class="lineno"> 32</span>  <span class="keyword">static</span> constexpr <span class="keywordtype">size_t</span> npos = <span class="keyword">static_cast<</span><span class="keywordtype">size_t</span><span class="keyword">></span>(-1);</div><div class="line"><a name="l00033"></a><span class="lineno"> 33</span>  static_assert(APT::StringView::npos == std::string::npos, <span class="stringliteral">"npos values are different"</span>);</div><div class="line"><a name="l00034"></a><span class="lineno"> 34</span> </div><div class="line"><a name="l00035"></a><span class="lineno"> 35</span>  <span class="comment">/* Constructors */</span></div><div class="line"><a name="l00036"></a><span class="lineno"> 36</span>  constexpr StringView() : data_(<span class="stringliteral">""</span>), size_(0) {}</div><div class="line"><a name="l00037"></a><span class="lineno"> 37</span>  constexpr StringView(<span class="keyword">const</span> <span class="keywordtype">char</span> *data, <span class="keywordtype">size_t</span> size) : data_(data), size_(size) {}</div><div class="line"><a name="l00038"></a><span class="lineno"> 38</span> </div><div class="line"><a name="l00039"></a><span class="lineno"> 39</span>  StringView(<span class="keyword">const</span> <span class="keywordtype">char</span> *data) : data_(data), size_(strlen(data)) {}</div><div class="line"><a name="l00040"></a><span class="lineno"> 40</span>  StringView(std::string <span class="keyword">const</span> & str): data_(str.data()), size_(str.size()) {}</div><div class="line"><a name="l00041"></a><span class="lineno"> 41</span> </div><div class="line"><a name="l00042"></a><span class="lineno"> 42</span> </div><div class="line"><a name="l00043"></a><span class="lineno"> 43</span>  <span class="comment">/* Viewers */</span></div><div class="line"><a name="l00044"></a><span class="lineno"> 44</span>  constexpr StringView substr(<span class="keywordtype">size_t</span> pos, <span class="keywordtype">size_t</span> n = npos)<span class="keyword"> const </span>{</div><div class="line"><a name="l00045"></a><span class="lineno"> 45</span>  <span class="keywordflow">return</span> StringView(data_ + pos, n > (size_ - pos) ? (size_ - pos) : n);</div><div class="line"><a name="l00046"></a><span class="lineno"> 46</span>  }</div><div class="line"><a name="l00047"></a><span class="lineno"> 47</span> </div><div class="line"><a name="l00048"></a><span class="lineno"> 48</span>  <span class="keywordtype">size_t</span> find(<span class="keywordtype">int</span> c, <span class="keywordtype">size_t</span> pos)<span class="keyword"> const </span>{</div><div class="line"><a name="l00049"></a><span class="lineno"> 49</span>  <span class="keywordflow">if</span> (pos == 0)</div><div class="line"><a name="l00050"></a><span class="lineno"> 50</span>  <span class="keywordflow">return</span> find(c);</div><div class="line"><a name="l00051"></a><span class="lineno"> 51</span>  <span class="keywordtype">size_t</span> <span class="keyword">const</span> found = substr(pos).find(c);</div><div class="line"><a name="l00052"></a><span class="lineno"> 52</span>  <span class="keywordflow">if</span> (found == npos)</div><div class="line"><a name="l00053"></a><span class="lineno"> 53</span>  <span class="keywordflow">return</span> npos;</div><div class="line"><a name="l00054"></a><span class="lineno"> 54</span>  <span class="keywordflow">return</span> pos + found;</div><div class="line"><a name="l00055"></a><span class="lineno"> 55</span>  }</div><div class="line"><a name="l00056"></a><span class="lineno"> 56</span>  <span class="keywordtype">size_t</span> find(<span class="keywordtype">int</span> c)<span class="keyword"> const </span>{</div><div class="line"><a name="l00057"></a><span class="lineno"> 57</span>  <span class="keyword">const</span> <span class="keywordtype">char</span> *found = <span class="keyword">static_cast<</span><span class="keyword">const </span><span class="keywordtype">char</span>*<span class="keyword">></span>(memchr(data_, c, size_));</div><div class="line"><a name="l00058"></a><span class="lineno"> 58</span> </div><div class="line"><a name="l00059"></a><span class="lineno"> 59</span>  <span class="keywordflow">if</span> (found == NULL)</div><div class="line"><a name="l00060"></a><span class="lineno"> 60</span>  <span class="keywordflow">return</span> npos;</div><div class="line"><a name="l00061"></a><span class="lineno"> 61</span> </div><div class="line"><a name="l00062"></a><span class="lineno"> 62</span>  <span class="keywordflow">return</span> found - data_;</div><div class="line"><a name="l00063"></a><span class="lineno"> 63</span>  }</div><div class="line"><a name="l00064"></a><span class="lineno"> 64</span> </div><div class="line"><a name="l00065"></a><span class="lineno"> 65</span>  <span class="keywordtype">size_t</span> rfind(<span class="keywordtype">int</span> c, <span class="keywordtype">size_t</span> pos)<span class="keyword"> const </span>{</div><div class="line"><a name="l00066"></a><span class="lineno"> 66</span>  <span class="keywordflow">if</span> (pos == npos)</div><div class="line"><a name="l00067"></a><span class="lineno"> 67</span>  <span class="keywordflow">return</span> rfind(c);</div><div class="line"><a name="l00068"></a><span class="lineno"> 68</span>  <span class="keywordflow">return</span> APT::StringView(data_, pos).rfind(c);</div><div class="line"><a name="l00069"></a><span class="lineno"> 69</span>  }</div><div class="line"><a name="l00070"></a><span class="lineno"> 70</span>  <span class="keywordtype">size_t</span> rfind(<span class="keywordtype">int</span> c)<span class="keyword"> const </span>{</div><div class="line"><a name="l00071"></a><span class="lineno"> 71</span>  <span class="keyword">const</span> <span class="keywordtype">char</span> *found = <span class="keyword">static_cast<</span><span class="keyword">const </span><span class="keywordtype">char</span>*<span class="keyword">></span>(memrchr(data_, c, size_));</div><div class="line"><a name="l00072"></a><span class="lineno"> 72</span> </div><div class="line"><a name="l00073"></a><span class="lineno"> 73</span>  <span class="keywordflow">if</span> (found == NULL)</div><div class="line"><a name="l00074"></a><span class="lineno"> 74</span>  <span class="keywordflow">return</span> npos;</div><div class="line"><a name="l00075"></a><span class="lineno"> 75</span> </div><div class="line"><a name="l00076"></a><span class="lineno"> 76</span>  <span class="keywordflow">return</span> found - data_;</div><div class="line"><a name="l00077"></a><span class="lineno"> 77</span>  }</div><div class="line"><a name="l00078"></a><span class="lineno"> 78</span> </div><div class="line"><a name="l00079"></a><span class="lineno"> 79</span>  <span class="comment">/* Conversions */</span></div><div class="line"><a name="l00080"></a><span class="lineno"> 80</span>  std::string to_string()<span class="keyword"> const </span>{</div><div class="line"><a name="l00081"></a><span class="lineno"> 81</span>  <span class="keywordflow">return</span> std::string(data_, size_);</div><div class="line"><a name="l00082"></a><span class="lineno"> 82</span>  }</div><div class="line"><a name="l00083"></a><span class="lineno"> 83</span> </div><div class="line"><a name="l00084"></a><span class="lineno"> 84</span>  <span class="comment">/* Comparisons */</span></div><div class="line"><a name="l00085"></a><span class="lineno"> 85</span>  <span class="keywordtype">int</span> compare(<span class="keywordtype">size_t</span> pos, <span class="keywordtype">size_t</span> n, StringView other)<span class="keyword"> const </span>{</div><div class="line"><a name="l00086"></a><span class="lineno"> 86</span>  <span class="keywordflow">return</span> substr(pos, n).compare(other);</div><div class="line"><a name="l00087"></a><span class="lineno"> 87</span>  }</div><div class="line"><a name="l00088"></a><span class="lineno"> 88</span> </div><div class="line"><a name="l00089"></a><span class="lineno"> 89</span>  <span class="keywordtype">int</span> compare(StringView other)<span class="keyword"> const </span>{</div><div class="line"><a name="l00090"></a><span class="lineno"> 90</span>  <span class="keywordtype">int</span> res;</div><div class="line"><a name="l00091"></a><span class="lineno"> 91</span> </div><div class="line"><a name="l00092"></a><span class="lineno"> 92</span>  res = memcmp(data_, other.data_, std::min(size_, other.size_));</div><div class="line"><a name="l00093"></a><span class="lineno"> 93</span>  <span class="keywordflow">if</span> (res != 0)</div><div class="line"><a name="l00094"></a><span class="lineno"> 94</span>  <span class="keywordflow">return</span> res;</div><div class="line"><a name="l00095"></a><span class="lineno"> 95</span>  <span class="keywordflow">if</span> (size_ == other.size_)</div><div class="line"><a name="l00096"></a><span class="lineno"> 96</span>  <span class="keywordflow">return</span> res;</div><div class="line"><a name="l00097"></a><span class="lineno"> 97</span> </div><div class="line"><a name="l00098"></a><span class="lineno"> 98</span>  <span class="keywordflow">return</span> (size_ > other.size_) ? 1 : -1;</div><div class="line"><a name="l00099"></a><span class="lineno"> 99</span>  }</div><div class="line"><a name="l00100"></a><span class="lineno"> 100</span> </div><div class="line"><a name="l00101"></a><span class="lineno"> 101</span>  <span class="comment">/* Optimization: If size not equal, string cannot be equal */</span></div><div class="line"><a name="l00102"></a><span class="lineno"> 102</span>  <span class="keywordtype">bool</span> operator ==(StringView other)<span class="keyword"> const </span>{ <span class="keywordflow">return</span> size_ == other.size_ && compare(other) == 0; }</div><div class="line"><a name="l00103"></a><span class="lineno"> 103</span>  <span class="keywordtype">bool</span> operator !=(StringView other)<span class="keyword"> const </span>{ <span class="keywordflow">return</span> !(*<span class="keyword">this</span> == other); }</div><div class="line"><a name="l00104"></a><span class="lineno"> 104</span> </div><div class="line"><a name="l00105"></a><span class="lineno"> 105</span>  <span class="comment">/* Accessors */</span></div><div class="line"><a name="l00106"></a><span class="lineno"> 106</span>  constexpr <span class="keywordtype">bool</span> empty()<span class="keyword"> const </span>{ <span class="keywordflow">return</span> size_ == 0; }</div><div class="line"><a name="l00107"></a><span class="lineno"> 107</span>  constexpr <span class="keyword">const</span> <span class="keywordtype">char</span>* data()<span class="keyword"> const </span>{ <span class="keywordflow">return</span> data_; }</div><div class="line"><a name="l00108"></a><span class="lineno"> 108</span>  constexpr <span class="keyword">const</span> <span class="keywordtype">char</span>* begin()<span class="keyword"> const </span>{ <span class="keywordflow">return</span> data_; }</div><div class="line"><a name="l00109"></a><span class="lineno"> 109</span>  constexpr <span class="keyword">const</span> <span class="keywordtype">char</span>* end()<span class="keyword"> const </span>{ <span class="keywordflow">return</span> data_ + size_; }</div><div class="line"><a name="l00110"></a><span class="lineno"> 110</span>  constexpr <span class="keywordtype">char</span> operator [](<span class="keywordtype">size_t</span> i)<span class="keyword"> const </span>{ <span class="keywordflow">return</span> data_[i]; }</div><div class="line"><a name="l00111"></a><span class="lineno"> 111</span>  constexpr <span class="keywordtype">size_t</span> size()<span class="keyword"> const </span>{ <span class="keywordflow">return</span> size_; }</div><div class="line"><a name="l00112"></a><span class="lineno"> 112</span>  constexpr <span class="keywordtype">size_t</span> length()<span class="keyword"> const </span>{ <span class="keywordflow">return</span> size_; }</div><div class="line"><a name="l00113"></a><span class="lineno"> 113</span> };</div><div class="line"><a name="l00114"></a><span class="lineno"> 114</span> </div><div class="line"><a name="l00119"></a><span class="lineno"> 119</span> <span class="keyword">static</span> <span class="keyword">inline</span> <span class="keywordtype">int</span> StringViewCompareFast(StringView a, StringView b) {</div><div class="line"><a name="l00120"></a><span class="lineno"> 120</span>  <span class="keywordflow">if</span> (a.size() != b.size())</div><div class="line"><a name="l00121"></a><span class="lineno"> 121</span>  <span class="keywordflow">return</span> a.size() - b.size();</div><div class="line"><a name="l00122"></a><span class="lineno"> 122</span> </div><div class="line"><a name="l00123"></a><span class="lineno"> 123</span>  <span class="keywordflow">return</span> memcmp(a.data(), b.data(), a.size());</div><div class="line"><a name="l00124"></a><span class="lineno"> 124</span> }</div><div class="line"><a name="l00125"></a><span class="lineno"> 125</span> </div><div class="line"><a name="l00126"></a><span class="lineno"> 126</span> </div><div class="line"><a name="l00127"></a><span class="lineno"> 127</span> }</div><div class="line"><a name="l00128"></a><span class="lineno"> 128</span> </div><div class="line"><a name="l00129"></a><span class="lineno"> 129</span> <span class="keyword">inline</span> <span class="keywordtype">bool</span> operator ==(<span class="keyword">const</span> <span class="keywordtype">char</span> *other, APT::StringView that);</div><div class="line"><a name="l00130"></a><span class="lineno"> 130</span> <span class="keyword">inline</span> <span class="keywordtype">bool</span> operator ==(<span class="keyword">const</span> <span class="keywordtype">char</span> *other, APT::StringView that) { <span class="keywordflow">return</span> that.operator==(other); }</div><div class="line"><a name="l00131"></a><span class="lineno"> 131</span> </div><div class="line"><a name="l00132"></a><span class="lineno"> 132</span> <span class="preprocessor">#endif</span></div><div class="ttc" id="namespaceAPT_xhtml"><div class="ttname"><a href="namespaceAPT.xhtml">APT</a></div><div class="ttdef"><b>Definition:</b> aptconfiguration.cc:34</div></div>
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