1 | // |
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2 | // Cforall Version 1.0.0 Copyright (C) 2016 University of Waterloo |
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3 | // |
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4 | // The contents of this file are covered under the licence agreement in the |
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5 | // file "LICENCE" distributed with Cforall. |
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6 | // |
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7 | // string_res -- variable-length, mutable run of text, with resource semantics |
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8 | // |
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9 | // Author : Michael L. Brooks |
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10 | // Created On : Fri Sep 03 11:00:00 2021 |
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11 | // Last Modified By : Michael L. Brooks |
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12 | // Last Modified On : Fri Sep 03 11:00:00 2021 |
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13 | // Update Count : 1 |
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14 | // |
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15 | |
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16 | #include "string_res.hfa" |
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17 | #include "string_sharectx.hfa" |
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18 | |
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19 | #include <stdlib.hfa> // e.g. malloc |
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20 | #include <string.h> // e.g. strlen |
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21 | #include <assert.h> |
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22 | |
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23 | //######################### VbyteHeap "header" ######################### |
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24 | |
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25 | #ifdef VbyteDebug |
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26 | HandleNode *HeaderPtr; |
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27 | #endif // VbyteDebug |
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28 | |
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29 | struct VbyteHeap { |
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30 | |
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31 | int NoOfCompactions; // number of compactions of the byte area |
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32 | int NoOfExtensions; // number of extensions in the size of the byte area |
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33 | int NoOfReductions; // number of reductions in the size of the byte area |
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34 | |
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35 | int InitSize; // initial number of bytes in the byte-string area |
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36 | int CurrSize; // current number of bytes in the byte-string area |
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37 | char *StartVbyte; // pointer to the `st byte of the start of the byte-string area |
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38 | char *EndVbyte; // pointer to the next byte after the end of the currently used portion of byte-string area |
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39 | void *ExtVbyte; // pointer to the next byte after the end of the byte-string area |
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40 | |
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41 | HandleNode Header; // header node for handle list |
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42 | }; // VbyteHeap |
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43 | |
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44 | |
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45 | static inline void compaction( VbyteHeap & ); // compaction of the byte area |
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46 | static inline void garbage( VbyteHeap &, int ); // garbage collect the byte area |
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47 | static inline void extend( VbyteHeap &, int ); // extend the size of the byte area |
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48 | static inline void reduce( VbyteHeap &, int ); // reduce the size of the byte area |
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49 | |
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50 | static inline void ?{}( VbyteHeap &, size_t = 1000 ); |
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51 | static inline void ^?{}( VbyteHeap & ); |
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52 | static inline void ByteCopy( char *, int, int, char *, int, int ); // copy a block of bytes from one location in the heap to another |
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53 | static inline int ByteCmp( char *, int, int, char *, int, int ); // compare 2 blocks of bytes |
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54 | static inline char *VbyteAlloc( VbyteHeap &, int ); // allocate a block bytes in the heap |
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55 | static inline char *VbyteTryAdjustLast( VbyteHeap &, int ); |
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56 | |
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57 | static inline void AddThisAfter( HandleNode &, HandleNode & ); |
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58 | static inline void DeleteNode( HandleNode & ); |
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59 | static inline void MoveThisAfter( HandleNode &, const HandleNode & ); // move current handle after parameter handle |
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60 | |
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61 | |
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62 | // Allocate the storage for the variable sized area and intialize the heap variables. |
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63 | |
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64 | static inline void ?{}( VbyteHeap & this, size_t Size ) with(this) { |
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65 | #ifdef VbyteDebug |
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66 | serr | "enter:VbyteHeap::VbyteHeap, this:" | &this | " Size:" | Size; |
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67 | #endif // VbyteDebug |
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68 | NoOfCompactions = NoOfExtensions = NoOfReductions = 0; |
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69 | InitSize = CurrSize = Size; |
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70 | StartVbyte = EndVbyte = alloc(CurrSize); |
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71 | ExtVbyte = (void *)( StartVbyte + CurrSize ); |
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72 | Header.flink = Header.blink = &Header; |
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73 | Header.ulink = & this; |
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74 | #ifdef VbyteDebug |
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75 | HeaderPtr = &Header; |
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76 | serr | "exit:VbyteHeap::VbyteHeap, this:" | &this; |
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77 | #endif // VbyteDebug |
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78 | } // VbyteHeap |
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79 | |
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80 | |
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81 | // Release the dynamically allocated storage for the byte area. |
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82 | |
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83 | static inline void ^?{}( VbyteHeap & this ) with(this) { |
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84 | free( StartVbyte ); |
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85 | } // ~VbyteHeap |
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86 | |
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87 | |
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88 | //######################### HandleNode ######################### |
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89 | |
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90 | |
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91 | // Create a handle node. The handle is not linked into the handle list. This is the responsibilitiy of the handle |
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92 | // creator. |
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93 | |
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94 | static inline void ?{}( HandleNode & this ) with(this) { |
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95 | #ifdef VbyteDebug |
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96 | serr | "enter:HandleNode::HandleNode, this:" | &this; |
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97 | #endif // VbyteDebug |
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98 | s = 0; |
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99 | lnth = 0; |
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100 | #ifdef VbyteDebug |
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101 | serr | "exit:HandleNode::HandleNode, this:" | &this; |
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102 | #endif // VbyteDebug |
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103 | } // HandleNode |
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104 | |
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105 | // Create a handle node. The handle is linked into the handle list at the end. This means that this handle will NOT be |
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106 | // in order by string address, but this is not a problem because a string with length zero does nothing during garbage |
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107 | // collection. |
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108 | |
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109 | static inline void ?{}( HandleNode & this, VbyteHeap & vh ) with(this) { |
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110 | #ifdef VbyteDebug |
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111 | serr | "enter:HandleNode::HandleNode, this:" | &this; |
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112 | #endif // VbyteDebug |
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113 | s = 0; |
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114 | lnth = 0; |
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115 | ulink = &vh; |
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116 | AddThisAfter( this, *vh.Header.blink ); |
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117 | #ifdef VbyteDebug |
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118 | serr | "exit:HandleNode::HandleNode, this:" | &this; |
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119 | #endif // VbyteDebug |
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120 | } // HandleNode |
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121 | |
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122 | |
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123 | // Delete a node from the handle list by unchaining it from the list. If the handle node was allocated dynamically, it |
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124 | // is the responsibility of the creator to destroy it. |
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125 | |
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126 | static inline void ^?{}( HandleNode & this ) with(this) { |
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127 | #ifdef VbyteDebug |
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128 | serr | "enter:HandleNode::~HandleNode, this:" | & this; |
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129 | { |
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130 | serr | nlOff; |
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131 | serr | " lnth:" | lnth | " s:" | (void *)s | ",\""; |
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132 | for ( int i = 0; i < lnth; i += 1 ) { |
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133 | serr | s[i]; |
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134 | } // for |
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135 | serr | "\" flink:" | flink | " blink:" | blink | nl; |
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136 | serr | nlOn; |
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137 | } |
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138 | #endif // VbyteDebug |
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139 | DeleteNode( this ); |
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140 | } // ~HandleNode |
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141 | |
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142 | |
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143 | //######################### String Sharing Context ######################### |
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144 | |
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145 | static string_sharectx * ambient_string_sharectx; // fickle top of stack |
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146 | static string_sharectx default_string_sharectx = {NEW_SHARING}; // stable bottom of stack |
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147 | |
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148 | void ?{}( string_sharectx & this, StringSharectx_Mode mode ) with( this ) { |
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149 | (older){ ambient_string_sharectx }; |
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150 | if ( mode == NEW_SHARING ) { |
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151 | (activeHeap){ new( (size_t) 1000 ) }; |
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152 | } else { |
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153 | verify( mode == NO_SHARING ); |
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154 | (activeHeap){ 0p }; |
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155 | } |
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156 | ambient_string_sharectx = & this; |
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157 | } |
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158 | |
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159 | void ^?{}( string_sharectx & this ) with( this ) { |
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160 | if ( activeHeap ) delete( activeHeap ); |
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161 | |
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162 | // unlink this from older-list starting from ambient_string_sharectx |
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163 | // usually, this==ambient_string_sharectx and the loop runs zero times |
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164 | string_sharectx *& c = ambient_string_sharectx; |
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165 | while ( c != &this ) &c = &c->older; // find this |
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166 | c = this.older; // unlink |
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167 | } |
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168 | |
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169 | //######################### String Resource ######################### |
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170 | |
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171 | |
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172 | VbyteHeap * DEBUG_string_heap() { |
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173 | assert( ambient_string_sharectx->activeHeap && "No sharing context is active" ); |
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174 | return ambient_string_sharectx->activeHeap; |
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175 | } |
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176 | |
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177 | size_t DEBUG_string_bytes_avail_until_gc( VbyteHeap * heap ) { |
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178 | return ((char*)heap->ExtVbyte) - heap->EndVbyte; |
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179 | } |
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180 | |
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181 | size_t DEBUG_string_bytes_in_heap( VbyteHeap * heap ) { |
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182 | return heap->CurrSize; |
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183 | } |
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184 | |
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185 | const char * DEBUG_string_heap_start( VbyteHeap * heap ) { |
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186 | return heap->StartVbyte; |
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187 | } |
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188 | |
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189 | // Returns the size of the string in bytes |
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190 | size_t size(const string_res &s) with(s) { |
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191 | return Handle.lnth; |
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192 | } |
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193 | |
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194 | // Output operator |
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195 | ofstream & ?|?(ofstream &out, const string_res &s) { |
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196 | // Store auto-newline state so it can be restored |
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197 | bool anl = getANL$(out); |
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198 | nlOff(out); |
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199 | for (size_t i = 0; i < s.Handle.lnth; i++) { |
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200 | out | s[i]; |
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201 | } |
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202 | out | sep; |
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203 | // Re-apply newlines after done, for chaining version |
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204 | if (anl) nlOn(out); |
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205 | return out; |
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206 | } |
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207 | |
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208 | void ?|?(ofstream &out, const string_res &s) { |
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209 | // Store auto-newline state so it can be restored |
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210 | bool anl = getANL$(out); |
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211 | nlOff(out); |
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212 | for (size_t i = 0; i < s.Handle.lnth; i++) { |
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213 | // Need to re-apply on the last output operator, for whole-statement version |
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214 | if (anl && i == s.Handle.lnth-1) nlOn(out); |
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215 | out | s[i]; |
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216 | } |
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217 | return out; |
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218 | } |
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219 | |
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220 | // Empty constructor |
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221 | void ?{}(string_res &s) with(s) { |
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222 | if( ambient_string_sharectx->activeHeap ) { |
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223 | (Handle){ * ambient_string_sharectx->activeHeap }; |
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224 | (shareEditSet_owns_ulink){ false }; |
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225 | } else { |
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226 | (Handle){ * new( (size_t) 10 ) }; // TODO: can I lazily avoid allocating for empty string |
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227 | (shareEditSet_owns_ulink){ true }; |
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228 | } |
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229 | s.shareEditSet_prev = &s; |
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230 | s.shareEditSet_next = &s; |
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231 | } |
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232 | |
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233 | static inline void eagerCopyCtorHelper(string_res &s, const char* rhs, size_t rhslnth) with(s) { |
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234 | if( ambient_string_sharectx->activeHeap ) { |
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235 | (Handle){ * ambient_string_sharectx->activeHeap }; |
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236 | (shareEditSet_owns_ulink){ false }; |
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237 | } else { |
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238 | (Handle){ * new( rhslnth ) }; |
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239 | (shareEditSet_owns_ulink){ true }; |
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240 | } |
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241 | Handle.s = VbyteAlloc(*Handle.ulink, rhslnth); |
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242 | Handle.lnth = rhslnth; |
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243 | for ( int i = 0; i < rhslnth; i += 1 ) { // copy characters |
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244 | Handle.s[i] = rhs[i]; |
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245 | } // for |
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246 | s.shareEditSet_prev = &s; |
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247 | s.shareEditSet_next = &s; |
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248 | } |
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249 | |
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250 | // Constructor from a raw buffer and size |
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251 | void ?{}(string_res &s, const char* rhs, size_t rhslnth) with(s) { |
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252 | eagerCopyCtorHelper(s, rhs, rhslnth); |
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253 | } |
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254 | |
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255 | // String literal constructor |
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256 | void ?{}(string_res &s, const char* rhs) { |
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257 | (s){ rhs, strlen(rhs) }; |
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258 | } |
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259 | |
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260 | // General copy constructor |
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261 | void ?{}(string_res &s, const string_res & s2, StrResInitMode mode, size_t start, size_t end ) { |
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262 | |
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263 | verify( start <= end && end <= s2.Handle.lnth ); |
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264 | |
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265 | if (s2.Handle.ulink == ambient_string_sharectx->activeHeap) { |
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266 | // same heap: allow overlap |
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267 | (s.Handle){}; |
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268 | s.Handle.s = s2.Handle.s + start; |
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269 | s.Handle.lnth = end - start; |
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270 | s.Handle.ulink = ambient_string_sharectx->activeHeap; |
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271 | (s.shareEditSet_owns_ulink){ false }; |
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272 | AddThisAfter(s.Handle, s2.Handle ); // insert this handle after rhs handle |
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273 | // ^ bug? skip others at early point in string |
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274 | |
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275 | if (mode == COPY_VALUE) { |
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276 | // make s alone in its shareEditSet |
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277 | s.shareEditSet_prev = &s; |
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278 | s.shareEditSet_next = &s; |
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279 | } else { |
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280 | verify( mode == SHARE_EDITS ); |
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281 | |
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282 | // s2 is logically const but not implementation const |
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283 | string_res & s2mod = (string_res &) s2; |
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284 | |
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285 | // insert s after s2 on shareEditSet |
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286 | s.shareEditSet_next = s2mod.shareEditSet_next; |
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287 | s.shareEditSet_prev = &s2mod; |
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288 | s.shareEditSet_next->shareEditSet_prev = &s; |
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289 | s.shareEditSet_prev->shareEditSet_next = &s; |
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290 | } |
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291 | } else { |
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292 | // crossing heaps: eager copy |
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293 | assert( mode == COPY_VALUE && "need to solidify context-crossing rules for requesting shared edits"); |
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294 | eagerCopyCtorHelper(s, s2.Handle.s + start, end - start); |
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295 | verify(s.shareEditSet_prev == &s); |
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296 | verify(s.shareEditSet_next == &s); |
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297 | } |
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298 | } |
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299 | |
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300 | static void assignEditSet(string_res & this, string_res * shareEditSetStartPeer, string_res * shareEditSetEndPeer, |
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301 | char * resultSesStart, |
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302 | size_t resultSesLnth, |
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303 | HandleNode * resultPadPosition, size_t bsize ) { |
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304 | |
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305 | char * beforeBegin = shareEditSetStartPeer->Handle.s; |
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306 | size_t beforeLen = this.Handle.s - beforeBegin; |
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307 | |
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308 | char * afterBegin = this.Handle.s + this.Handle.lnth; |
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309 | size_t afterLen = shareEditSetEndPeer->Handle.s + shareEditSetEndPeer->Handle.lnth - afterBegin; |
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310 | |
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311 | size_t oldLnth = this.Handle.lnth; |
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312 | |
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313 | this.Handle.s = resultSesStart + beforeLen; |
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314 | this.Handle.lnth = bsize; |
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315 | if (resultPadPosition) |
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316 | MoveThisAfter( this.Handle, *resultPadPosition ); |
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317 | |
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318 | // adjust all substring string and handle locations, and check if any substring strings are outside the new base string |
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319 | char *limit = resultSesStart + resultSesLnth; |
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320 | for (string_res * p = this.shareEditSet_next; p != &this; p = p->shareEditSet_next) { |
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321 | verify (p->Handle.s >= beforeBegin); |
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322 | if ( p->Handle.s >= afterBegin ) { |
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323 | verify ( p->Handle.s <= afterBegin + afterLen ); |
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324 | verify ( p->Handle.s + p->Handle.lnth <= afterBegin + afterLen ); |
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325 | // p starts after the edit |
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326 | // take start and end as end-anchored |
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327 | size_t startOffsetFromEnd = afterBegin + afterLen - p->Handle.s; |
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328 | p->Handle.s = limit - startOffsetFromEnd; |
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329 | // p->Handle.lnth unaffected |
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330 | } else if ( p->Handle.s <= beforeBegin + beforeLen ) { |
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331 | // p starts before, or at the start of, the edit |
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332 | if ( p->Handle.s + p->Handle.lnth <= beforeBegin + beforeLen ) { |
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333 | // p ends before the edit |
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334 | // take end as start-anchored too |
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335 | // p->Handle.lnth unaffected |
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336 | } else if ( p->Handle.s + p->Handle.lnth < afterBegin ) { |
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337 | // p ends during the edit; p does not include the last character replaced |
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338 | // clip end of p to end at start of edit |
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339 | p->Handle.lnth = beforeLen - ( p->Handle.s - beforeBegin ); |
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340 | } else { |
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341 | // p ends after the edit |
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342 | verify ( p->Handle.s + p->Handle.lnth <= afterBegin + afterLen ); |
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343 | // take end as end-anchored |
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344 | // stretch-shrink p according to the edit |
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345 | p->Handle.lnth += this.Handle.lnth; |
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346 | p->Handle.lnth -= oldLnth; |
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347 | } |
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348 | // take start as start-anchored |
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349 | size_t startOffsetFromStart = p->Handle.s - beforeBegin; |
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350 | p->Handle.s = resultSesStart + startOffsetFromStart; |
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351 | } else { |
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352 | verify ( p->Handle.s < afterBegin ); |
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353 | // p starts during the edit |
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354 | verify( p->Handle.s + p->Handle.lnth >= beforeBegin + beforeLen ); |
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355 | if ( p->Handle.s + p->Handle.lnth < afterBegin ) { |
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356 | // p ends during the edit; p does not include the last character replaced |
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357 | // set p to empty string at start of edit |
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358 | p->Handle.s = this.Handle.s; |
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359 | p->Handle.lnth = 0; |
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360 | } else { |
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361 | // p includes the end of the edit |
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362 | // clip start of p to start at end of edit |
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363 | int charsToClip = afterBegin - p->Handle.s; |
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364 | p->Handle.s = this.Handle.s + this.Handle.lnth; |
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365 | p->Handle.lnth -= charsToClip; |
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366 | } |
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367 | } |
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368 | if (resultPadPosition) |
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369 | MoveThisAfter( p->Handle, *resultPadPosition ); // move substring handle to maintain sorted order by string position |
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370 | } |
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371 | } |
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372 | |
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373 | static void assign_(string_res &this, const char* buffer, size_t bsize, const string_res & valSrc) { |
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374 | |
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375 | // traverse the incumbent share-edit set (SES) to recover the range of a base string to which `this` belongs |
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376 | string_res * shareEditSetStartPeer = & this; |
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377 | string_res * shareEditSetEndPeer = & this; |
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378 | for (string_res * editPeer = this.shareEditSet_next; editPeer != &this; editPeer = editPeer->shareEditSet_next) { |
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379 | if ( editPeer->Handle.s < shareEditSetStartPeer->Handle.s ) { |
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380 | shareEditSetStartPeer = editPeer; |
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381 | } |
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382 | if ( shareEditSetEndPeer->Handle.s + shareEditSetEndPeer->Handle.lnth < editPeer->Handle.s + editPeer->Handle.lnth) { |
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383 | shareEditSetEndPeer = editPeer; |
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384 | } |
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385 | } |
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386 | |
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387 | verify( shareEditSetEndPeer->Handle.s >= shareEditSetStartPeer->Handle.s ); |
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388 | size_t editSetLength = shareEditSetEndPeer->Handle.s + shareEditSetEndPeer->Handle.lnth - shareEditSetStartPeer->Handle.s; |
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389 | verify( editSetLength >= this.Handle.lnth ); |
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390 | |
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391 | if ( this.shareEditSet_owns_ulink ) { // assigning to private context |
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392 | // ok to overwrite old value within LHS |
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393 | char * prefixStartOrig = shareEditSetStartPeer->Handle.s; |
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394 | int prefixLen = this.Handle.s - prefixStartOrig; |
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395 | char * suffixStartOrig = this.Handle.s + this.Handle.lnth; |
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396 | int suffixLen = shareEditSetEndPeer->Handle.s + shareEditSetEndPeer->Handle.lnth - suffixStartOrig; |
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397 | |
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398 | int delta = bsize - this.Handle.lnth; |
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399 | if ( char * oldBytes = VbyteTryAdjustLast( *this.Handle.ulink, delta ) ) { |
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400 | // growing: copy from old to new |
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401 | char * dest = VbyteAlloc( *this.Handle.ulink, editSetLength ); |
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402 | char *destCursor = dest; memcpy(destCursor, prefixStartOrig, prefixLen); |
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403 | destCursor += prefixLen; memcpy(destCursor, buffer , bsize ); |
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404 | destCursor += this.Handle.lnth; memcpy(destCursor, suffixStartOrig, suffixLen); |
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405 | assignEditSet(this, shareEditSetStartPeer, shareEditSetEndPeer, |
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406 | dest, |
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407 | editSetLength, |
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408 | 0p, bsize); |
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409 | free( oldBytes ); |
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410 | } else { |
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411 | // room is already allocated in-place: bubble suffix and overwite middle |
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412 | memmove( suffixStartOrig + delta, suffixStartOrig, suffixLen ); |
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413 | memcpy( this.Handle.s, buffer, bsize ); |
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414 | |
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415 | assignEditSet(this, shareEditSetStartPeer, shareEditSetEndPeer, |
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416 | shareEditSetStartPeer->Handle.s, |
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417 | editSetLength, |
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418 | 0p, bsize); |
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419 | } |
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420 | |
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421 | } else if ( // assigning to shared context |
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422 | this.Handle.lnth == editSetLength && // overwriting entire run of SES |
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423 | & valSrc && // sourcing from a managed string |
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424 | valSrc.Handle.ulink == this.Handle.ulink ) { // sourcing from same heap |
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425 | |
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426 | // SES's result will only use characters from the source string => reuse source |
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427 | assignEditSet(this, shareEditSetStartPeer, shareEditSetEndPeer, |
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428 | valSrc.Handle.s, |
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429 | valSrc.Handle.lnth, |
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430 | &((string_res&)valSrc).Handle, bsize); |
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431 | |
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432 | } else { |
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433 | // overwriting a proper substring of some string: mash characters from old and new together (copy on write) |
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434 | // OR we are importing characters: need to copy eagerly (can't refer to source) |
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435 | |
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436 | // full string is from start of shareEditSetStartPeer thru end of shareEditSetEndPeer |
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437 | // `this` occurs in the middle of it, to be replaced |
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438 | // build up the new text in `pasting` |
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439 | |
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440 | // super private string ctor: ignore ambient context |
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441 | void ?{}( string_res &s, VbyteHeap & heap, const char* rhs, size_t rhslnth ) with(s) { |
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442 | (Handle){ heap }; |
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443 | Handle.s = VbyteAlloc(*Handle.ulink, rhslnth); |
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444 | Handle.lnth = rhslnth; |
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445 | (s.shareEditSet_owns_ulink){ false }; |
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446 | for ( int i = 0; i < rhslnth; i += 1 ) { // copy characters |
---|
447 | Handle.s[i] = rhs[i]; |
---|
448 | } // for |
---|
449 | s.shareEditSet_prev = &s; |
---|
450 | s.shareEditSet_next = &s; |
---|
451 | } |
---|
452 | |
---|
453 | string_res pasting = { |
---|
454 | * this.Handle.ulink, // maintain same heap, regardless of context |
---|
455 | shareEditSetStartPeer->Handle.s, // start of SES |
---|
456 | this.Handle.s - shareEditSetStartPeer->Handle.s }; // length of SES, before this |
---|
457 | append( pasting, |
---|
458 | buffer, // start of replacement for this |
---|
459 | bsize ); // length of replacement for this |
---|
460 | append( pasting, |
---|
461 | this.Handle.s + this.Handle.lnth, // start of SES after this |
---|
462 | shareEditSetEndPeer->Handle.s + shareEditSetEndPeer->Handle.lnth - |
---|
463 | (this.Handle.s + this.Handle.lnth) ); // length of SES, after this |
---|
464 | |
---|
465 | // The above string building can trigger compaction. |
---|
466 | // The reference points (that are arguments of the string building) may move during that building. |
---|
467 | // From this point on, they are stable. |
---|
468 | |
---|
469 | assignEditSet(this, shareEditSetStartPeer, shareEditSetEndPeer, |
---|
470 | pasting.Handle.s, |
---|
471 | pasting.Handle.lnth, |
---|
472 | &pasting.Handle, bsize); |
---|
473 | } |
---|
474 | } |
---|
475 | |
---|
476 | void assign(string_res &this, const char* buffer, size_t bsize) { |
---|
477 | assign_(this, buffer, bsize, *0p); |
---|
478 | } |
---|
479 | |
---|
480 | void ?=?(string_res &s, const char* other) { |
---|
481 | assign(s, other, strlen(other)); |
---|
482 | } |
---|
483 | |
---|
484 | void ?=?(string_res &s, char other) { |
---|
485 | assign(s, &other, 1); |
---|
486 | } |
---|
487 | |
---|
488 | // Copy assignment operator |
---|
489 | void ?=?(string_res & this, const string_res & rhs) with( this ) { |
---|
490 | assign_(this, rhs.Handle.s, rhs.Handle.lnth, rhs); |
---|
491 | } |
---|
492 | |
---|
493 | void ?=?(string_res & this, string_res & rhs) with( this ) { |
---|
494 | const string_res & rhs2 = rhs; |
---|
495 | this = rhs2; |
---|
496 | } |
---|
497 | |
---|
498 | |
---|
499 | // Destructor |
---|
500 | void ^?{}(string_res &s) with(s) { |
---|
501 | // much delegated to implied ^VbyteSM |
---|
502 | |
---|
503 | // sever s from its share-edit peers, if any (four no-ops when already solo) |
---|
504 | s.shareEditSet_prev->shareEditSet_next = s.shareEditSet_next; |
---|
505 | s.shareEditSet_next->shareEditSet_prev = s.shareEditSet_prev; |
---|
506 | // s.shareEditSet_next = &s; |
---|
507 | // s.shareEditSet_prev = &s; |
---|
508 | |
---|
509 | if (shareEditSet_owns_ulink && s.shareEditSet_next == &s) { // last one out |
---|
510 | delete( s.Handle.ulink ); |
---|
511 | } |
---|
512 | } |
---|
513 | |
---|
514 | |
---|
515 | // Returns the character at the given index |
---|
516 | // With unicode support, this may be different from just the byte at the given |
---|
517 | // offset from the start of the string. |
---|
518 | char ?[?](const string_res &s, size_t index) with(s) { |
---|
519 | //TODO: Check if index is valid (no exceptions yet) |
---|
520 | return Handle.s[index]; |
---|
521 | } |
---|
522 | |
---|
523 | void assignAt(const string_res &s, size_t index, char val) { |
---|
524 | string_res editZone = { s, SHARE_EDITS, index, index+1 }; |
---|
525 | assign(editZone, &val, 1); |
---|
526 | } |
---|
527 | |
---|
528 | |
---|
529 | /////////////////////////////////////////////////////////////////// |
---|
530 | // Concatenation |
---|
531 | |
---|
532 | void append(string_res &str1, const char * buffer, size_t bsize) { |
---|
533 | size_t clnth = size(str1) + bsize; |
---|
534 | if ( str1.Handle.s + size(str1) == buffer ) { // already juxtapose ? |
---|
535 | // no-op |
---|
536 | } else { // must copy some text |
---|
537 | if ( str1.Handle.s + size(str1) == VbyteAlloc(*str1.Handle.ulink, 0) ) { // str1 at end of string area ? |
---|
538 | VbyteAlloc( *str1.Handle.ulink, bsize ); // create room for 2nd part at the end of string area |
---|
539 | } else { // copy the two parts |
---|
540 | char * str1oldBuf = str1.Handle.s; |
---|
541 | str1.Handle.s = VbyteAlloc( *str1.Handle.ulink, clnth ); |
---|
542 | ByteCopy( str1.Handle.s, 0, str1.Handle.lnth, str1oldBuf, 0, str1.Handle.lnth); |
---|
543 | } // if |
---|
544 | ByteCopy( str1.Handle.s, str1.Handle.lnth, bsize, (char*)buffer, 0, (int)bsize); |
---|
545 | // VbyteHeap & this, char *Dst, int DstStart, int DstLnth, char *Src, int SrcStart, int SrcLnth |
---|
546 | } // if |
---|
547 | str1.Handle.lnth = clnth; |
---|
548 | } |
---|
549 | |
---|
550 | void ?+=?(string_res &str1, const string_res &str2) { |
---|
551 | append( str1, str2.Handle.s, str2.Handle.lnth ); |
---|
552 | } |
---|
553 | |
---|
554 | void ?+=?(string_res &s, char other) { |
---|
555 | append( s, &other, 1 ); |
---|
556 | } |
---|
557 | |
---|
558 | void ?+=?(string_res &s, const char* other) { |
---|
559 | append( s, other, strlen(other) ); |
---|
560 | } |
---|
561 | |
---|
562 | |
---|
563 | |
---|
564 | |
---|
565 | ////////////////////////////////////////////////////////// |
---|
566 | // Comparisons |
---|
567 | |
---|
568 | |
---|
569 | bool ?==?(const string_res &s1, const string_res &s2) { |
---|
570 | return ByteCmp( s1.Handle.s, 0, s1.Handle.lnth, s2.Handle.s, 0, s2.Handle.lnth) == 0; |
---|
571 | } |
---|
572 | |
---|
573 | bool ?!=?(const string_res &s1, const string_res &s2) { |
---|
574 | return !(s1 == s2); |
---|
575 | } |
---|
576 | bool ?==?(const string_res &s, const char* other) { |
---|
577 | string_res sother = other; |
---|
578 | return s == sother; |
---|
579 | } |
---|
580 | bool ?!=?(const string_res &s, const char* other) { |
---|
581 | return !(s == other); |
---|
582 | } |
---|
583 | |
---|
584 | |
---|
585 | ////////////////////////////////////////////////////////// |
---|
586 | // Search |
---|
587 | |
---|
588 | bool contains(const string_res &s, char ch) { |
---|
589 | for (i; size(s)) { |
---|
590 | if (s[i] == ch) return true; |
---|
591 | } |
---|
592 | return false; |
---|
593 | } |
---|
594 | |
---|
595 | int find(const string_res &s, char search) { |
---|
596 | for (i; size(s)) { |
---|
597 | if (s[i] == search) return i; |
---|
598 | } |
---|
599 | return size(s); |
---|
600 | } |
---|
601 | |
---|
602 | /* Remaining implementations essentially ported from Sunjay's work */ |
---|
603 | |
---|
604 | int find(const string_res &s, const string_res &search) { |
---|
605 | return find(s, search.Handle.s, search.Handle.lnth); |
---|
606 | } |
---|
607 | |
---|
608 | int find(const string_res &s, const char* search) { |
---|
609 | return find(s, search, strlen(search)); |
---|
610 | } |
---|
611 | |
---|
612 | int find(const string_res &s, const char* search, size_t searchsize) { |
---|
613 | // FIXME: This is a naive algorithm. We probably want to switch to someting |
---|
614 | // like Boyer-Moore in the future. |
---|
615 | // https://en.wikipedia.org/wiki/String_searching_algorithm |
---|
616 | |
---|
617 | // Always find the empty string |
---|
618 | if (searchsize == 0) { |
---|
619 | return 0; |
---|
620 | } |
---|
621 | |
---|
622 | for (size_t i = 0; i < s.Handle.lnth; i++) { |
---|
623 | size_t remaining = s.Handle.lnth - i; |
---|
624 | // Never going to find the search string if the remaining string is |
---|
625 | // smaller than search |
---|
626 | if (remaining < searchsize) { |
---|
627 | break; |
---|
628 | } |
---|
629 | |
---|
630 | bool matched = true; |
---|
631 | for (size_t j = 0; j < searchsize; j++) { |
---|
632 | if (search[j] != s.Handle.s[i + j]) { |
---|
633 | matched = false; |
---|
634 | break; |
---|
635 | } |
---|
636 | } |
---|
637 | if (matched) { |
---|
638 | return i; |
---|
639 | } |
---|
640 | } |
---|
641 | |
---|
642 | return s.Handle.lnth; |
---|
643 | } |
---|
644 | |
---|
645 | bool includes(const string_res &s, const string_res &search) { |
---|
646 | return includes(s, search.Handle.s, search.Handle.lnth); |
---|
647 | } |
---|
648 | |
---|
649 | bool includes(const string_res &s, const char* search) { |
---|
650 | return includes(s, search, strlen(search)); |
---|
651 | } |
---|
652 | |
---|
653 | bool includes(const string_res &s, const char* search, size_t searchsize) { |
---|
654 | return find(s, search, searchsize) < s.Handle.lnth; |
---|
655 | } |
---|
656 | |
---|
657 | bool startsWith(const string_res &s, const string_res &prefix) { |
---|
658 | return startsWith(s, prefix.Handle.s, prefix.Handle.lnth); |
---|
659 | } |
---|
660 | |
---|
661 | bool startsWith(const string_res &s, const char* prefix) { |
---|
662 | return startsWith(s, prefix, strlen(prefix)); |
---|
663 | } |
---|
664 | |
---|
665 | bool startsWith(const string_res &s, const char* prefix, size_t prefixsize) { |
---|
666 | if (s.Handle.lnth < prefixsize) { |
---|
667 | return false; |
---|
668 | } |
---|
669 | return memcmp(s.Handle.s, prefix, prefixsize) == 0; |
---|
670 | } |
---|
671 | |
---|
672 | bool endsWith(const string_res &s, const string_res &suffix) { |
---|
673 | return endsWith(s, suffix.Handle.s, suffix.Handle.lnth); |
---|
674 | } |
---|
675 | |
---|
676 | bool endsWith(const string_res &s, const char* suffix) { |
---|
677 | return endsWith(s, suffix, strlen(suffix)); |
---|
678 | } |
---|
679 | |
---|
680 | bool endsWith(const string_res &s, const char* suffix, size_t suffixsize) { |
---|
681 | if (s.Handle.lnth < suffixsize) { |
---|
682 | return false; |
---|
683 | } |
---|
684 | // Amount to offset the bytes pointer so that we are comparing the end of s |
---|
685 | // to suffix. s.bytes + offset should be the first byte to compare against suffix |
---|
686 | size_t offset = s.Handle.lnth - suffixsize; |
---|
687 | return memcmp(s.Handle.s + offset, suffix, suffixsize) == 0; |
---|
688 | } |
---|
689 | |
---|
690 | /* Back to Mike's work */ |
---|
691 | |
---|
692 | |
---|
693 | /////////////////////////////////////////////////////////////////////////// |
---|
694 | // charclass, include, exclude |
---|
695 | |
---|
696 | void ?{}( charclass_res & this, const string_res & chars) { |
---|
697 | (this){ chars.Handle.s, chars.Handle.lnth }; |
---|
698 | } |
---|
699 | |
---|
700 | void ?{}( charclass_res & this, const char * chars ) { |
---|
701 | (this){ chars, strlen(chars) }; |
---|
702 | } |
---|
703 | |
---|
704 | void ?{}( charclass_res & this, const char * chars, size_t charssize ) { |
---|
705 | (this.chars){ chars, charssize }; |
---|
706 | // now sort it ? |
---|
707 | } |
---|
708 | |
---|
709 | void ^?{}( charclass_res & this ) { |
---|
710 | ^(this.chars){}; |
---|
711 | } |
---|
712 | |
---|
713 | static bool test( const charclass_res & mask, char c ) { |
---|
714 | // instead, use sorted char list? |
---|
715 | return contains( mask.chars, c ); |
---|
716 | } |
---|
717 | |
---|
718 | int exclude(const string_res &s, const charclass_res &mask) { |
---|
719 | for (int i = 0; i < size(s); i++) { |
---|
720 | if ( test(mask, s[i]) ) return i; |
---|
721 | } |
---|
722 | return size(s); |
---|
723 | } |
---|
724 | |
---|
725 | int include(const string_res &s, const charclass_res &mask) { |
---|
726 | for (int i = 0; i < size(s); i++) { |
---|
727 | if ( ! test(mask, s[i]) ) return i; |
---|
728 | } |
---|
729 | return size(s); |
---|
730 | } |
---|
731 | |
---|
732 | //######################### VbyteHeap "implementation" ######################### |
---|
733 | |
---|
734 | |
---|
735 | // Add a new HandleNode node n after the current HandleNode node. |
---|
736 | |
---|
737 | static inline void AddThisAfter( HandleNode & this, HandleNode & n ) with(this) { |
---|
738 | #ifdef VbyteDebug |
---|
739 | serr | "enter:AddThisAfter, this:" | &this | " n:" | &n; |
---|
740 | #endif // VbyteDebug |
---|
741 | verify( n.ulink != 0p ); |
---|
742 | verify( this.ulink == n.ulink ); |
---|
743 | flink = n.flink; |
---|
744 | blink = &n; |
---|
745 | n.flink->blink = &this; |
---|
746 | n.flink = &this; |
---|
747 | #ifdef VbyteDebug |
---|
748 | { |
---|
749 | serr | "HandleList:"; |
---|
750 | serr | nlOff; |
---|
751 | for ( HandleNode *ni = HeaderPtr->flink; ni != HeaderPtr; ni = ni->flink ) { |
---|
752 | serr | "\tnode:" | ni | " lnth:" | ni->lnth | " s:" | (void *)ni->s | ",\""; |
---|
753 | for ( int i = 0; i < ni->lnth; i += 1 ) { |
---|
754 | serr | ni->s[i]; |
---|
755 | } // for |
---|
756 | serr | "\" flink:" | ni->flink | " blink:" | ni->blink | nl; |
---|
757 | } // for |
---|
758 | serr | nlOn; |
---|
759 | } |
---|
760 | serr | "exit:AddThisAfter"; |
---|
761 | #endif // VbyteDebug |
---|
762 | } // AddThisAfter |
---|
763 | |
---|
764 | |
---|
765 | // Delete the current HandleNode node. |
---|
766 | |
---|
767 | static inline void DeleteNode( HandleNode & this ) with(this) { |
---|
768 | #ifdef VbyteDebug |
---|
769 | serr | "enter:DeleteNode, this:" | &this; |
---|
770 | #endif // VbyteDebug |
---|
771 | flink->blink = blink; |
---|
772 | blink->flink = flink; |
---|
773 | #ifdef VbyteDebug |
---|
774 | serr | "exit:DeleteNode"; |
---|
775 | #endif // VbyteDebug |
---|
776 | } // DeleteNode |
---|
777 | |
---|
778 | |
---|
779 | |
---|
780 | // Allocates specified storage for a string from byte-string area. If not enough space remains to perform the |
---|
781 | // allocation, the garbage collection routine is called. |
---|
782 | |
---|
783 | static inline char * VbyteAlloc( VbyteHeap & this, int size ) with(this) { |
---|
784 | #ifdef VbyteDebug |
---|
785 | serr | "enter:VbyteAlloc, size:" | size; |
---|
786 | #endif // VbyteDebug |
---|
787 | uintptr_t NoBytes; |
---|
788 | char *r; |
---|
789 | |
---|
790 | NoBytes = ( uintptr_t )EndVbyte + size; |
---|
791 | if ( NoBytes > ( uintptr_t )ExtVbyte ) { // enough room for new byte-string ? |
---|
792 | garbage( this, size ); // firer up the garbage collector |
---|
793 | NoBytes = ( uintptr_t )EndVbyte + size; // try again |
---|
794 | if ( NoBytes > ( uintptr_t )ExtVbyte ) { // enough room for new byte-string ? |
---|
795 | assert( 0 && "garbage run did not free up required space" ); |
---|
796 | } // if |
---|
797 | } // if |
---|
798 | r = EndVbyte; |
---|
799 | EndVbyte += size; |
---|
800 | #ifdef VbyteDebug |
---|
801 | serr | "exit:VbyteAlloc, r:" | (void *)r | " EndVbyte:" | (void *)EndVbyte | " ExtVbyte:" | ExtVbyte; |
---|
802 | #endif // VbyteDebug |
---|
803 | return r; |
---|
804 | } // VbyteAlloc |
---|
805 | |
---|
806 | |
---|
807 | // Adjusts the last allocation in this heap by delta bytes, or resets this heap to be able to offer |
---|
808 | // new allocations of its original size + delta bytes. Positive delta means bigger; |
---|
809 | // negative means smaller. A null return indicates that the original heap location has room for |
---|
810 | // the requested growth. A non-null return indicates that copying to a new location is required |
---|
811 | // but has not been done; the returned value is the old heap storage location; `this` heap is |
---|
812 | // modified to reference the new location. In the copy-requred case, the caller should use |
---|
813 | // VbyteAlloc to claim the new space, while doing optimal copying from old to new, then free old. |
---|
814 | |
---|
815 | static inline char * VbyteTryAdjustLast( VbyteHeap & this, int delta ) with(this) { |
---|
816 | |
---|
817 | if ( ( uintptr_t )EndVbyte + delta <= ( uintptr_t )ExtVbyte ) { |
---|
818 | // room available |
---|
819 | EndVbyte += delta; |
---|
820 | return 0p; |
---|
821 | } |
---|
822 | |
---|
823 | char *oldBytes = StartVbyte; |
---|
824 | |
---|
825 | NoOfExtensions += 1; |
---|
826 | CurrSize *= 2; |
---|
827 | StartVbyte = EndVbyte = alloc(CurrSize); |
---|
828 | ExtVbyte = StartVbyte + CurrSize; |
---|
829 | |
---|
830 | return oldBytes; |
---|
831 | } |
---|
832 | |
---|
833 | |
---|
834 | // Move an existing HandleNode node h somewhere after the current HandleNode node so that it is in ascending order by |
---|
835 | // the address in the byte string area. |
---|
836 | |
---|
837 | static inline void MoveThisAfter( HandleNode & this, const HandleNode & h ) with(this) { |
---|
838 | #ifdef VbyteDebug |
---|
839 | serr | "enter:MoveThisAfter, this:" | & this | " h:" | & h; |
---|
840 | #endif // VbyteDebug |
---|
841 | verify( h.ulink != 0p ); |
---|
842 | verify( this.ulink == h.ulink ); |
---|
843 | if ( s < h.s ) { // check argument values |
---|
844 | // serr | "VbyteSM: Error - Cannot move byte string starting at:" | s | " after byte string starting at:" |
---|
845 | // | ( h->s ) | " and keep handles in ascending order"; |
---|
846 | // exit(-1 ); |
---|
847 | verify( 0 && "VbyteSM: Error - Cannot move byte strings as requested and keep handles in ascending order"); |
---|
848 | } // if |
---|
849 | |
---|
850 | HandleNode *i; |
---|
851 | for ( i = h.flink; i->s != 0 && s > ( i->s ); i = i->flink ); // find the position for this node after h |
---|
852 | if ( & this != i->blink ) { |
---|
853 | DeleteNode( this ); |
---|
854 | AddThisAfter( this, *i->blink ); |
---|
855 | } // if |
---|
856 | #ifdef VbyteDebug |
---|
857 | { |
---|
858 | serr | "HandleList:"; |
---|
859 | serr | nlOff; |
---|
860 | for ( HandleNode *n = HeaderPtr->flink; n != HeaderPtr; n = n->flink ) { |
---|
861 | serr | "\tnode:" | n | " lnth:" | n->lnth | " s:" | (void *)n->s | ",\""; |
---|
862 | for ( int i = 0; i < n->lnth; i += 1 ) { |
---|
863 | serr | n->s[i]; |
---|
864 | } // for |
---|
865 | serr | "\" flink:" | n->flink | " blink:" | n->blink | nl; |
---|
866 | } // for |
---|
867 | serr | nlOn; |
---|
868 | } |
---|
869 | serr | "exit:MoveThisAfter"; |
---|
870 | #endif // VbyteDebug |
---|
871 | } // MoveThisAfter |
---|
872 | |
---|
873 | |
---|
874 | |
---|
875 | |
---|
876 | |
---|
877 | //######################### VbyteHeap ######################### |
---|
878 | |
---|
879 | // Move characters from one location in the byte-string area to another. The routine handles the following situations: |
---|
880 | // |
---|
881 | // if the |Src| > |Dst| => truncate |
---|
882 | // if the |Dst| > |Src| => pad Dst with blanks |
---|
883 | |
---|
884 | void ByteCopy( char *Dst, int DstStart, int DstLnth, char *Src, int SrcStart, int SrcLnth ) { |
---|
885 | for ( int i = 0; i < DstLnth; i += 1 ) { |
---|
886 | if ( i == SrcLnth ) { // |Dst| > |Src| |
---|
887 | for ( ; i < DstLnth; i += 1 ) { // pad Dst with blanks |
---|
888 | Dst[DstStart + i] = ' '; |
---|
889 | } // for |
---|
890 | break; |
---|
891 | } // exit |
---|
892 | Dst[DstStart + i] = Src[SrcStart + i]; |
---|
893 | } // for |
---|
894 | } // ByteCopy |
---|
895 | |
---|
896 | // Compare two byte strings in the byte-string area. The routine returns the following values: |
---|
897 | // |
---|
898 | // 1 => Src1-byte-string > Src2-byte-string |
---|
899 | // 0 => Src1-byte-string = Src2-byte-string |
---|
900 | // -1 => Src1-byte-string < Src2-byte-string |
---|
901 | |
---|
902 | int ByteCmp( char *Src1, int Src1Start, int Src1Lnth, char *Src2, int Src2Start, int Src2Lnth ) { |
---|
903 | #ifdef VbyteDebug |
---|
904 | serr | "enter:ByteCmp, Src1Start:" | Src1Start | " Src1Lnth:" | Src1Lnth | " Src2Start:" | Src2Start | " Src2Lnth:" | Src2Lnth; |
---|
905 | #endif // VbyteDebug |
---|
906 | int cmp; |
---|
907 | |
---|
908 | CharZip: for ( int i = 0; ; i += 1 ) { |
---|
909 | if ( i == Src2Lnth - 1 ) { |
---|
910 | for ( ; ; i += 1 ) { |
---|
911 | if ( i == Src1Lnth - 1 ) { |
---|
912 | cmp = 0; |
---|
913 | break CharZip; |
---|
914 | } // exit |
---|
915 | if ( Src1[Src1Start + i] != ' ') { |
---|
916 | // SUSPECTED BUG: this could be be why Peter got the bug report about == " " (why is this case here at all?) |
---|
917 | cmp = 1; |
---|
918 | break CharZip; |
---|
919 | } // exit |
---|
920 | } // for |
---|
921 | } // exit |
---|
922 | if ( i == Src1Lnth - 1 ) { |
---|
923 | for ( ; ; i += 1 ) { |
---|
924 | if ( i == Src2Lnth - 1 ) { |
---|
925 | cmp = 0; |
---|
926 | break CharZip; |
---|
927 | } // exit |
---|
928 | if ( Src2[Src2Start + i] != ' ') { |
---|
929 | cmp = -1; |
---|
930 | break CharZip; |
---|
931 | } // exit |
---|
932 | } // for |
---|
933 | } // exit |
---|
934 | if ( Src2[Src2Start + i] != Src1[Src1Start+ i]) { |
---|
935 | cmp = Src1[Src1Start + i] > Src2[Src2Start + i] ? 1 : -1; |
---|
936 | break CharZip; |
---|
937 | } // exit |
---|
938 | } // for |
---|
939 | #ifdef VbyteDebug |
---|
940 | serr | "exit:ByteCmp, cmp:" | cmp; |
---|
941 | #endif // VbyteDebug |
---|
942 | return cmp; |
---|
943 | } // ByteCmp |
---|
944 | |
---|
945 | |
---|
946 | // The compaction moves all of the byte strings currently in use to the beginning of the byte-string area and modifies |
---|
947 | // the handles to reflect the new positions of the byte strings. Compaction assumes that the handle list is in ascending |
---|
948 | // order by pointers into the byte-string area. The strings associated with substrings do not have to be moved because |
---|
949 | // the containing string has been moved. Hence, they only require that their string pointers be adjusted. |
---|
950 | |
---|
951 | void compaction(VbyteHeap & this) with(this) { |
---|
952 | HandleNode *h; |
---|
953 | char *obase, *nbase, *limit; |
---|
954 | |
---|
955 | NoOfCompactions += 1; |
---|
956 | EndVbyte = StartVbyte; |
---|
957 | h = Header.flink; // ignore header node |
---|
958 | for (;;) { |
---|
959 | ByteCopy( EndVbyte, 0, h->lnth, h->s, 0, h->lnth ); |
---|
960 | obase = h->s; |
---|
961 | h->s = EndVbyte; |
---|
962 | nbase = h->s; |
---|
963 | EndVbyte += h->lnth; |
---|
964 | limit = obase + h->lnth; |
---|
965 | h = h->flink; |
---|
966 | |
---|
967 | // check if any substrings are allocated within a string |
---|
968 | |
---|
969 | for (;;) { |
---|
970 | if ( h == &Header ) break; // end of header list ? |
---|
971 | if ( h->s >= limit ) break; // outside of current string ? |
---|
972 | h->s = nbase + (( uintptr_t )h->s - ( uintptr_t )obase ); |
---|
973 | h = h->flink; |
---|
974 | } // for |
---|
975 | if ( h == &Header ) break; // end of header list ? |
---|
976 | } // for |
---|
977 | } // compaction |
---|
978 | |
---|
979 | |
---|
980 | // Garbage determines the amount of free space left in the heap and then reduces, leave the same, or extends the size of |
---|
981 | // the heap. The heap is then compacted in the existing heap or into the newly allocated heap. |
---|
982 | |
---|
983 | void garbage(VbyteHeap & this, int minreq ) with(this) { |
---|
984 | #ifdef VbyteDebug |
---|
985 | serr | "enter:garbage"; |
---|
986 | { |
---|
987 | serr | "HandleList:"; |
---|
988 | for ( HandleNode *n = Header.flink; n != &Header; n = n->flink ) { |
---|
989 | serr | nlOff; |
---|
990 | serr | "\tnode:" | n | " lnth:" | n->lnth | " s:" | (void *)n->s | ",\""; |
---|
991 | for ( int i = 0; i < n->lnth; i += 1 ) { |
---|
992 | serr | n->s[i]; |
---|
993 | } // for |
---|
994 | serr | nlOn; |
---|
995 | serr | "\" flink:" | n->flink | " blink:" | n->blink; |
---|
996 | } // for |
---|
997 | } |
---|
998 | #endif // VbyteDebug |
---|
999 | int AmountUsed, AmountFree; |
---|
1000 | |
---|
1001 | AmountUsed = 0; |
---|
1002 | for ( HandleNode *i = Header.flink; i != &Header; i = i->flink ) { // calculate amount of byte area used |
---|
1003 | AmountUsed += i->lnth; |
---|
1004 | } // for |
---|
1005 | AmountFree = ( uintptr_t )ExtVbyte - ( uintptr_t )StartVbyte - AmountUsed; |
---|
1006 | |
---|
1007 | if ( ( double ) AmountFree < ( CurrSize * 0.1 ) || AmountFree < minreq ) { // free space less than 10% or not enough to serve cur request |
---|
1008 | |
---|
1009 | extend( this, max( CurrSize, minreq ) ); // extend the heap |
---|
1010 | |
---|
1011 | // Peter says, "This needs work before it should be used." |
---|
1012 | // } else if ( AmountFree > CurrSize / 2 ) { // free space greater than 3 times the initial allocation ? |
---|
1013 | // reduce(( AmountFree / CurrSize - 3 ) * CurrSize ); // reduce the memory |
---|
1014 | |
---|
1015 | } // if |
---|
1016 | compaction(this); // compact the byte area, in the same or new heap area |
---|
1017 | #ifdef VbyteDebug |
---|
1018 | { |
---|
1019 | serr | "HandleList:"; |
---|
1020 | for ( HandleNode *n = Header.flink; n != &Header; n = n->flink ) { |
---|
1021 | serr | nlOff; |
---|
1022 | serr | "\tnode:" | n | " lnth:" | n->lnth | " s:" | (void *)n->s | ",\""; |
---|
1023 | for ( int i = 0; i < n->lnth; i += 1 ) { |
---|
1024 | serr | n->s[i]; |
---|
1025 | } // for |
---|
1026 | serr | nlOn; |
---|
1027 | serr | "\" flink:" | n->flink | " blink:" | n->blink; |
---|
1028 | } // for |
---|
1029 | } |
---|
1030 | serr | "exit:garbage"; |
---|
1031 | #endif // VbyteDebug |
---|
1032 | } // garbage |
---|
1033 | |
---|
1034 | #undef VbyteDebug |
---|
1035 | |
---|
1036 | |
---|
1037 | |
---|
1038 | // Extend the size of the byte-string area by creating a new area and copying the old area into it. The old byte-string |
---|
1039 | // area is deleted. |
---|
1040 | |
---|
1041 | void extend( VbyteHeap & this, int size ) with (this) { |
---|
1042 | #ifdef VbyteDebug |
---|
1043 | serr | "enter:extend, size:" | size; |
---|
1044 | #endif // VbyteDebug |
---|
1045 | char *OldStartVbyte; |
---|
1046 | |
---|
1047 | NoOfExtensions += 1; |
---|
1048 | OldStartVbyte = StartVbyte; // save previous byte area |
---|
1049 | |
---|
1050 | CurrSize += size > InitSize ? size : InitSize; // minimum extension, initial size |
---|
1051 | StartVbyte = EndVbyte = alloc(CurrSize); |
---|
1052 | ExtVbyte = (void *)( StartVbyte + CurrSize ); |
---|
1053 | compaction(this); // copy from old heap to new & adjust pointers to new heap |
---|
1054 | free( OldStartVbyte ); // release old heap |
---|
1055 | #ifdef VbyteDebug |
---|
1056 | serr | "exit:extend, CurrSize:" | CurrSize; |
---|
1057 | #endif // VbyteDebug |
---|
1058 | } // extend |
---|
1059 | |
---|
1060 | //WIP |
---|
1061 | #if 0 |
---|
1062 | |
---|
1063 | // Extend the size of the byte-string area by creating a new area and copying the old area into it. The old byte-string |
---|
1064 | // area is deleted. |
---|
1065 | |
---|
1066 | void VbyteHeap::reduce( int size ) { |
---|
1067 | #ifdef VbyteDebug |
---|
1068 | serr | "enter:reduce, size:" | size; |
---|
1069 | #endif // VbyteDebug |
---|
1070 | char *OldStartVbyte; |
---|
1071 | |
---|
1072 | NoOfReductions += 1; |
---|
1073 | OldStartVbyte = StartVbyte; // save previous byte area |
---|
1074 | |
---|
1075 | CurrSize -= size; |
---|
1076 | StartVbyte = EndVbyte = new char[CurrSize]; |
---|
1077 | ExtVbyte = (void *)( StartVbyte + CurrSize ); |
---|
1078 | compaction(); // copy from old heap to new & adjust pointers to new heap |
---|
1079 | delete OldStartVbyte; // release old heap |
---|
1080 | #ifdef VbyteDebug |
---|
1081 | serr | "exit:reduce, CurrSize:" | CurrSize; |
---|
1082 | #endif // VbyteDebug |
---|
1083 | } // reduce |
---|
1084 | |
---|
1085 | |
---|
1086 | #endif |
---|