1 files changed, 74 insertions, 0 deletions
diff --git a/lib/Support/Errno.cpp b/lib/Support/Errno.cpp
new file mode 100644
index 00000000000..dd218f60990
--- /dev/null
+++ b/lib/Support/Errno.cpp
@@ -0,0 +1,74 @@
+//===- 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, MaxErrStrLen - 1, 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