src/error/SysErrorDetail.h

   1 /*
   2  * Copyright (C) 1996-2020 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 #ifndef _SQUID_SRC_ERROR_SYSERRORDETAIL_H
  10 #define _SQUID_SRC_ERROR_SYSERRORDETAIL_H
  11
  12 #include "error/Detail.h"
  13 #include "sbuf/SBuf.h"
  14 #include "sbuf/Stream.h"
  15
  16 /// system call failure detail based on standard errno(3)/strerror(3) APIs
  17 class SysErrorDetail: public ErrorDetail
  18 {
  19     MEMPROXY_CLASS(SysErrorDetail);
  20
  21 public:
  22     /// \returns a pointer to a SysErrorDetail instance (or nil for lost errnos)
  23     static ErrorDetail::Pointer NewIfAny(const int errorNo)
  24     {
  25         // we could optimize by caching results for (frequently used?) errnos
  26         return errorNo ? new SysErrorDetail(errorNo) : nullptr;
  27     }
  28
  29     static SBuf Brief(int errorNo) {
  30         return SysErrorDetail(errorNo).brief();
  31     }
  32
  33     /* ErrorDetail API */
  34     virtual SBuf brief() const override {
  35         return ToSBuf("errno=", errorNo);
  36     }
  37
  38     virtual SBuf verbose(const HttpRequestPointer &) const override {
  39         return SBuf(strerror(errorNo));
  40     }
  41
  42 private:
  43     // hidden by NewIfAny() to avoid creating SysErrorDetail from zero errno
  44     explicit SysErrorDetail(const int anErrorNo): errorNo(anErrorNo) {}
  45
  46     int errorNo; ///< errno(3) set by the last failed system call or equivalent
  47 };
  48
  49 #endif /* _SQUID_SRC_ERROR_SYSERRORDETAIL_H */
  50