src/base/RegexPattern.cc

   1 /*
   2  * Copyright (C) 1996-2025 The Squid Software Foundation and contributors
   3  *
   4  * Squid software is distributed under GPLv2+ license and includes
   5  * contributions from numerous individuals and organizations.
   6  * Please see the COPYING and CONTRIBUTORS files for details.
   7  */
   8
   9 #include "squid.h"
  10 #include "base/RegexPattern.h"
  11 #include "base/TextException.h"
  12 #include "debug/Stream.h"
  13 #include "sbuf/Stream.h"
  14
  15 #include <iostream>
  16 #include <utility>
  17
  18 RegexPattern::RegexPattern(const SBuf &aPattern, const int aFlags):
  19     pattern(aPattern),
  20     flags(aFlags)
  21 {
  22     memset(&regex, 0, sizeof(regex)); // paranoid; POSIX does not require this
  23     if (const auto errCode = regcomp(&regex, pattern.c_str(), flags)) {
  24         char errBuf[256];
  25         // for simplicity, ignore any error message truncation
  26         (void)regerror(errCode, &regex, errBuf, sizeof(errBuf));
  27         // POSIX examples show no regfree(&regex) after a regcomp() error;
  28         // presumably, regcom() frees any allocated memory on failures
  29         throw TextException(ToSBuf("POSIX regcomp(3) failure: (", errCode, ") ", errBuf,
  30                                    Debug::Extra, "regular expression: ", pattern), Here());
  31     }
  32
  33     debugs(28, 2, *this);
  34 }
  35
  36 RegexPattern::~RegexPattern()
  37 {
  38     regfree(&regex);
  39 }
  40
  41 void
  42 RegexPattern::print(std::ostream &os, const RegexPattern * const previous) const
  43 {
  44     // report context-dependent explicit options and delimiters
  45     if (!previous) {
  46         // do not report default settings
  47         if (!caseSensitive())
  48             os << "-i ";
  49     } else {
  50         os << ' '; // separate us from the previous value
  51
  52         // do not report same-as-previous (i.e. inherited) settings
  53         if (previous->flags != flags)
  54             os << (caseSensitive() ? "+i " : "-i ");
  55     }
  56
  57     os << pattern;
  58 }
  59