1 /* 2 * lineranges.h 3 * 4 * Created on: Sep 17, 2008 5 * Author: Lorenzo Bettini <http://www.lorenzobettini.it>, (C) 2008 6 * Copyright: See COPYING file that comes with this distribution 7 */ 8 9 #ifndef LINERANGES_H_ 10 #define LINERANGES_H_ 11 12 #include <set> 13 #include <string> 14 15 namespace srchilite { 16 17 /// a possible error in specifying a range 18 enum RangeError { 19 NO_ERROR = 0, INVALID_RANGE_NUMBER 20 }; 21 22 /// result for a check whether a number is in a range (or in a context) 23 enum RangeResult { 24 NOT_IN_RANGE = 0, CONTEXT_RANGE, IN_RANGE 25 }; 26 27 /** 28 * Functionalities for detecting whether a line is in one of the 29 * stored line ranges (or in the context of a range). 30 * 31 * This also performs some optimization: ranges are stored in a set 32 * in ascending order; if we have ranges, e.g., 1-20, 50-70, 100-200, and 33 * we check whether 23 is in range, we first check if it's in 1-20, then, 34 * since it's not there, we check whether it's in 50-70; it is not, and since the 35 * range is 50-70 it makes no sense searching for it in other ranges. The next search 36 * will start from range 50-70, since we assume that line numbers are always increasing. 37 */ 38 class LineRanges { 39 public: 40 LineRanges(unsigned int contextLines = 0); 41 ~LineRanges(); 42 43 typedef int RangeElemType; 44 typedef std::pair<RangeElemType, RangeElemType> RangeType; 45 46 typedef std::set<RangeType> LineRangeSet; 47 48 /** 49 * Adds a range to the set. 50 * The argument can be: 51 * 52 * - a single element (means only one line) 53 * - a complete range (e.g., 20-35) 54 * - a partial range (e.g., 10- : from line 10 to the end, 55 * -20 : from the beginning to line 20) 56 * 57 * @param range the string representing the range. 58 * @return code specifying a possible error 59 */ 60 RangeError addRange(const std::string &range); 61 getLineRangeSet()62 const LineRangeSet &getLineRangeSet() const { 63 return lineRangeSet; 64 } 65 66 /** 67 * The next isInRange search will start from the first element of 68 * the set. This should be called before searching for lines of a file, 69 * that we started to process. 70 */ reset()71 void reset() { 72 searchFromTheStart = true; 73 } 74 75 /** 76 * Checks whether the passed element is in a range of this set. 77 * If it's not in the range it might be in the surrounding context. 78 * 79 * @param e 80 * @return whether the passed element is in a range or in the surrounding context. 81 */ 82 RangeResult isInRange(const RangeElemType e); 83 setContextLines(unsigned int context)84 void setContextLines(unsigned int context) { 85 contextLines = context; 86 } 87 88 private: 89 LineRangeSet lineRangeSet; 90 91 /** 92 * whether to perform the search from the first element of the set 93 */ 94 bool searchFromTheStart; 95 96 /** 97 * The current range for performing the search of isInRange. 98 */ 99 LineRangeSet::const_iterator currentRange; 100 101 /** 102 * The number of lines making the context (i.e., the number of lines 103 * that are not part of a range but are in the specified line number context) 104 */ 105 int contextLines; 106 }; 107 108 } 109 110 #endif /* LINERANGES_H_ */ 111