llvm/lib/Support/Errno.cpp
NAKAMURA Takumi e29b0aca51 lib/Support/Errno.cpp: Check strerror_s() with HAVE_DECL_STRERROR_S in config.h.*.
AC_CHECK_FUNCS seeks a symbol only in libs. We should check the declaration in string.h.

FIXME: I have never seen mingw(s) have strerror_s() (not _strerror_s()).
FIXME: Autoconf/CMake may seek strerror_s() with the definition MINGW_HAS_SECURE_API in future.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125172 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-09 04:18:48 +00:00

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2.1 KiB
C++

//===- Errno.cpp - errno support --------------------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the errno wrappers.
//
//===----------------------------------------------------------------------===//
#include "llvm/Support/Errno.h"
#include "llvm/Config/config.h" // Get autoconf configuration settings
#if HAVE_STRING_H
#include <string.h>
#if HAVE_ERRNO_H
#include <errno.h>
#endif
//===----------------------------------------------------------------------===//
//=== WARNING: Implementation here must contain only TRULY operating system
//=== independent code.
//===----------------------------------------------------------------------===//
namespace llvm {
namespace sys {
#if HAVE_ERRNO_H
std::string StrError() {
return StrError(errno);
}
#endif // HAVE_ERRNO_H
std::string StrError(int errnum) {
const int MaxErrStrLen = 2000;
char buffer[MaxErrStrLen];
buffer[0] = '\0';
char* str = buffer;
#ifdef HAVE_STRERROR_R
// strerror_r is thread-safe.
if (errnum)
# if defined(__GLIBC__) && defined(_GNU_SOURCE)
// glibc defines its own incompatible version of strerror_r
// which may not use the buffer supplied.
str = strerror_r(errnum,buffer,MaxErrStrLen-1);
# else
strerror_r(errnum,buffer,MaxErrStrLen-1);
# endif
#elif HAVE_DECL_STRERROR_S // "Windows Secure API"
if (errnum)
strerror_s(buffer, errnum);
#elif defined(HAVE_STRERROR)
// Copy the thread un-safe result of strerror into
// the buffer as fast as possible to minimize impact
// of collision of strerror in multiple threads.
if (errnum)
strncpy(buffer,strerror(errnum),MaxErrStrLen-1);
buffer[MaxErrStrLen-1] = '\0';
#else
// Strange that this system doesn't even have strerror
// but, oh well, just use a generic message
sprintf(buffer, "Error #%d", errnum);
#endif
return str;
}
} // namespace sys
} // namespace llvm
#endif // HAVE_STRING_H