This is the first step in adding sane error handling support to LLVMSystem.

The system API's will be shifted over to returning an error_code, and returning
other return values as out parameters to the function.

Code that needs to check error conditions will use the errc enum values which
are the same as the posix_errno defines (EBADF, E2BIG, etc...), and are
compatable with the error codes in WinError.h due to some magic in system_error.

An example would be:

if (error_code ec = KillEvil("Java")) { // error_code can be converted to bool.
  handle_error(ec);
}

llvm-svn: 119360

1 files changed, 34 insertions, 0 deletions

diff --git a/llvm/lib/System/Unix/system_error.inc b/llvm/lib/System/Unix/system_error.inc
new file mode 100644
index 00000000000..a382214877f
--- /dev/null
+++ b/llvm/lib/System/Unix/system_error.inc
@@ -0,0 +1,34 @@
+//===- llvm/System/Unix/system_error.inc - Unix error_code ------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file provides the Unix specific implementation of the error_code
+// and error_condition classes.
+//
+//===----------------------------------------------------------------------===//
+
+//===----------------------------------------------------------------------===//
+//=== WARNING: Implementation here must contain only generic UNIX code that
+//===          is guaranteed to work on *all* UNIX variants.
+//===----------------------------------------------------------------------===//
+
+using namespace llvm;
+
+std::string
+_system_error_category::message(int ev) const {
+  return _do_message::message(ev);
+}
+
+error_condition
+_system_error_category::default_error_condition(int ev) const {
+#ifdef ELAST
+  if (ev > ELAST)
+    return error_condition(ev, system_category());
+#endif  // ELAST
+  return error_condition(ev, generic_category());
+}