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      1 /**
      2  * @file string_manip.cpp
      3  * std::string helpers
      4  *
      5  * @remark Copyright 2002 OProfile authors
      6  * @remark Read the file COPYING
      7  *
      8  * @author Philippe Elie
      9  * @author John Levon
     10  */
     11 
     12 #include <sstream>
     13 #include <iomanip>
     14 
     15 #include <cstdlib>
     16 #include <cmath>
     17 
     18 #include "string_manip.h"
     19 
     20 using namespace std;
     21 
     22 
     23 string erase_to_last_of(string const & str, char ch)
     24 {
     25 	string result = str;
     26 	string::size_type pos = result.find_last_of(ch);
     27 	if (pos != string::npos)
     28 		result.erase(0, pos + 1);
     29 
     30 	return result;
     31 }
     32 
     33 
     34 string split(string & s, char c)
     35 {
     36 	string::size_type i = s.find_first_of(c);
     37 	if (i == string::npos)
     38 		return string();
     39 
     40 	string const tail = s.substr(i + 1);
     41 	s = s.substr(0, i);
     42 	return tail;
     43 }
     44 
     45 
     46 bool is_prefix(string const & s, string const & prefix)
     47 {
     48 	// gcc 2.95 and below don't have this
     49 	// return s.compare(0, prefix.length(), prefix) == 0;
     50 	return s.find(prefix) == 0;
     51 }
     52 
     53 
     54 vector<string> separate_token(string const & str, char sep)
     55 {
     56 	vector<string> result;
     57 	string next;
     58 
     59 	for (size_t pos = 0 ; pos != str.length() ; ++pos) {
     60 		char ch = str[pos];
     61 		if (ch == '\\') {
     62 			if (pos < str.length() - 1 && str[pos + 1] == sep) {
     63 				++pos;
     64 				next += sep;
     65 			} else {
     66 				next += '\\';
     67 			}
     68 		} else if (ch == sep) {
     69 			result.push_back(next);
     70 			// some stl lacks string::clear()
     71 			next.erase(next.begin(), next.end());
     72 		} else {
     73 			next += ch;
     74 		}
     75 	}
     76 
     77 	if (!next.empty())
     78 		result.push_back(next);
     79 
     80 	return result;
     81 }
     82 
     83 
     84 string ltrim(string const & str, string const & totrim)
     85 {
     86 	string result(str);
     87 
     88 	return result.erase(0, result.find_first_not_of(totrim));
     89 }
     90 
     91 
     92 string rtrim(string const & str, string const & totrim)
     93 {
     94 	string result(str);
     95 
     96 	return result.erase(result.find_last_not_of(totrim) + 1);
     97 }
     98 
     99 
    100 string trim(string const & str, string const & totrim)
    101 {
    102 	return rtrim(ltrim(str, totrim), totrim);
    103 }
    104 
    105 
    106 string const
    107 format_percent(double value, size_t int_width, size_t fract_width, bool showpos)
    108 {
    109 	ostringstream os;
    110 
    111 	if (value == 0.0)
    112 		return string(int_width + fract_width, ' ') + "0";
    113 
    114 	if (showpos)
    115 		os.setf(ios::showpos);
    116 
    117 	if (fabs(value) > .001) {
    118 		// os << fixed << value unsupported by gcc 2.95
    119 		os.setf(ios::fixed, ios::floatfield);
    120 		os << setw(int_width + fract_width + 1)
    121 		   << setprecision(fract_width) << value;
    122 	} else {
    123 		// os << scientific << value unsupported by gcc 2.95
    124 		os.setf(ios::scientific, ios::floatfield);
    125 		os << setw(int_width + fract_width + 1)
    126 		   // - 3 to count exponent part
    127 		   << setprecision(fract_width - 3) << value;
    128 	}
    129 
    130 	string formatted = os.str();
    131 	if (is_prefix(formatted, "100."))
    132 		formatted.erase(formatted.size() - 1);
    133 	return formatted;
    134 }
    135 
    136 
    137 template <>
    138 unsigned int op_lexical_cast<unsigned int, string>(string const & str)
    139 {
    140 	char* endptr;
    141 
    142 	// 2.91.66 fix
    143 	unsigned long ret = 0;
    144 	ret = strtoul(str.c_str(), &endptr, 0);
    145 	if (*endptr)
    146 		throw invalid_argument("op_lexical_cast(\""+ str +"\")");
    147 	return ret;
    148 }
    149