1//===- llvm/Support/Unix/Host.inc -------------------------------*- 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 UNIX Host support.
11//
12//===----------------------------------------------------------------------===//
13
14//===----------------------------------------------------------------------===//
15//=== WARNING: Implementation here must contain only generic UNIX code that
16//===          is guaranteed to work on *all* UNIX variants.
17//===----------------------------------------------------------------------===//
18
19#include "Unix.h"
20#include "llvm/ADT/StringRef.h"
21#include "llvm/Config/config.h"
22#include <cctype>
23#include <string>
24#include <sys/utsname.h>
25
26using namespace llvm;
27
28static std::string getOSVersion() {
29  struct utsname info;
30
31  if (uname(&info))
32    return "";
33
34  return info.release;
35}
36
37static std::string updateTripleOSVersion(std::string TargetTripleString) {
38  // On darwin, we want to update the version to match that of the target.
39  std::string::size_type DarwinDashIdx = TargetTripleString.find("-darwin");
40  if (DarwinDashIdx != std::string::npos) {
41    TargetTripleString.resize(DarwinDashIdx + strlen("-darwin"));
42    TargetTripleString += getOSVersion();
43    return TargetTripleString;
44  }
45  std::string::size_type MacOSDashIdx = TargetTripleString.find("-macos");
46  if (MacOSDashIdx != std::string::npos) {
47    TargetTripleString.resize(MacOSDashIdx);
48    // Reset the OS to darwin as the OS version from `uname` doesn't use the
49    // macOS version scheme.
50    TargetTripleString += "-darwin";
51    TargetTripleString += getOSVersion();
52  }
53  return TargetTripleString;
54}
55
56std::string sys::getDefaultTargetTriple() {
57  std::string TargetTripleString =
58      updateTripleOSVersion(LLVM_DEFAULT_TARGET_TRIPLE);
59
60  // Override the default target with an environment variable named by
61  // LLVM_TARGET_TRIPLE_ENV.
62#if defined(LLVM_TARGET_TRIPLE_ENV)
63  if (const char *EnvTriple = std::getenv(LLVM_TARGET_TRIPLE_ENV))
64    TargetTripleString = EnvTriple;
65#endif
66
67  return TargetTripleString;
68}
69