Line data    Source code

       1             : //===- Errno.cpp - errno support --------------------------------*- C++ -*-===//
       2             : //
       3             : //                     The LLVM Compiler Infrastructure
       4             : //
       5             : // This file is distributed under the University of Illinois Open Source
       6             : // License. See LICENSE.TXT for details.
       7             : //
       8             : //===----------------------------------------------------------------------===//
       9             : //
      10             : // This file implements the errno wrappers.
      11             : //
      12             : //===----------------------------------------------------------------------===//
      13             : 
      14             : #include "llvm/Support/Errno.h"
      15             : #include "llvm/Config/config.h" // Get autoconf configuration settings
      16             : #include "llvm/Support/raw_ostream.h"
      17             : #include <string.h>
      18             : 
      19             : #if HAVE_ERRNO_H
      20             : #include <errno.h>
      21             : #endif
      22             : 
      23             : //===----------------------------------------------------------------------===//
      24             : //=== WARNING: Implementation here must contain only TRULY operating system
      25             : //===          independent code.
      26             : //===----------------------------------------------------------------------===//
      27             : 
      28             : namespace llvm {
      29             : namespace sys {
      30             : 
      31             : #if HAVE_ERRNO_H
      32           0 : std::string StrError() {
      33           0 :   return StrError(errno);
      34             : }
      35             : #endif  // HAVE_ERRNO_H
      36             : 
      37           1 : std::string StrError(int errnum) {
      38             :   std::string str;
      39           1 :   if (errnum == 0)
      40             :     return str;
      41             : #if defined(HAVE_STRERROR_R) || HAVE_DECL_STRERROR_S
      42             :   const int MaxErrStrLen = 2000;
      43             :   char buffer[MaxErrStrLen];
      44           0 :   buffer[0] = '\0';
      45             : #endif
      46             : 
      47             : #ifdef HAVE_STRERROR_R
      48             :   // strerror_r is thread-safe.
      49             : #if defined(__GLIBC__) && defined(_GNU_SOURCE)
      50             :   // glibc defines its own incompatible version of strerror_r
      51             :   // which may not use the buffer supplied.
      52           0 :   str = strerror_r(errnum, buffer, MaxErrStrLen - 1);
      53             : #else
      54             :   strerror_r(errnum, buffer, MaxErrStrLen - 1);
      55             :   str = buffer;
      56             : #endif
      57             : #elif HAVE_DECL_STRERROR_S // "Windows Secure API"
      58             :   strerror_s(buffer, MaxErrStrLen - 1, errnum);
      59             :   str = buffer;
      60             : #elif defined(HAVE_STRERROR)
      61             :   // Copy the thread un-safe result of strerror into
      62             :   // the buffer as fast as possible to minimize impact
      63             :   // of collision of strerror in multiple threads.
      64             :   str = strerror(errnum);
      65             : #else
      66             :   // Strange that this system doesn't even have strerror
      67             :   // but, oh well, just use a generic message
      68             :   raw_string_ostream stream(str);
      69             :   stream << "Error #" << errnum;
      70             :   stream.flush();
      71             : #endif
      72             :   return str;
      73             : }
      74             : 
      75             : }  // namespace sys
      76             : }  // namespace llvm