Introduce llvm::sys::path::home_directory.

[pcc]

Summary

This will be used by the line editor library to derive a default path to
the history file.

I've verified that the Windows bits build (with a mingw64 cross compiler)
but I haven't actually tested them.

[majnemer]

lib/Support/Unix/Path.inc

805 ↗

(On Diff #5601)

Have you considered falling back to getpwuid_r on SUSv3? Something like:

bufsize = 2048;

#ifdef _SC_GETPW_R_SIZE_MAX
if ((getpw_r_size_max = sysconf(_SC_GETPW_R_SIZE_MAX)) > 0)
  bufsize = (size_t)getpw_r_size_max;
#endif

uid = getuid();

buf = NULL;
do {
  if ((tbuf = realloc(buf, bufsize)) == NULL) {
    free(buf);
    return false;
  }
  buf = tbuf;
  err = getpwuid_r(uid, &pw, buf, bufsize, &tpw);
  bufsize *= 2;
} while (err == ERANGE);

if (err) {
  free(buf);
  return false;
}

if (!tpw || !pw.pw_dir)
  return false;

result.append(pw.pw_dir, pw.pw_dir + strlen(pw.pw_dir));
return true;

[yaron.keren]

SHGetFolderPath is Deprecated function, Microsoft suggests to use SHGetKnownFolderPath instead.

http://msdn.microsoft.com/en-us/library/windows/desktop/bb762181(v=vs.85).aspx

In any case, the easy way to get the AppData directory is getenv("LOCALAPPDATA").

[pcc]

• Clear result on success

lib/Support/Unix/Path.inc

805 ↗

(On Diff #5601)

My understanding (from reading the getpwuid_r man page) is that user programs should be checking $HOME. If $HOME is not set, the user probably doesn't want the program using any directory as their home directory.

[pcc]

Closed by commit rL200594 (authored by @pcc).

llvm/trunk/include/llvm/Support/Path.h

 /// @param erasedOnReboot Whether to favor a path that is erased on reboot
 /// rather than one that potentially persists longer. This parameter will be
 /// ignored if the user or system has set the typical environment variable
 /// (e.g., TEMP on Windows, TMPDIR on *nix) to specify a temporary directory.
 ///
 /// @param result Holds the resulting path name.
 void system_temp_directory(bool erasedOnReboot, SmallVectorImpl<char> &result);
 
+/// @brief Get the user's home directory.
+///
+/// @param result Holds the resulting path name.
+/// @result True if a home directory is set, false otherwise.
+bool home_directory(SmallVectorImpl<char> &result);
+
 /// @brief Has root name?
 ///
 /// root_name != ""
 ///
 /// @param path Input path.
 /// @result True if the path has a root name, false otherwise.
 bool has_root_name(const Twine &path);
 

llvm/trunk/lib/Support/Unix/Path.inc

error_code openFileForWrite(const Twine &Name, int &ResultFD,
   while ((ResultFD = open(P.begin(), OpenFlags, Mode)) < 0) {
     if (errno != EINTR)
       return error_code(errno, system_category());
   }
   return error_code::success();
 }
 
 } // end namespace fs
+
+namespace path {
+
+bool home_directory(SmallVectorImpl<char> &result) {
+  if (char *RequestedDir = getenv("HOME")) {
+    result.clear();
+    result.append(RequestedDir, RequestedDir + strlen(RequestedDir));
+    return true;
+  }
+
+  return false;
+}
+
+} // end namespace path
+
 } // end namespace sys
 } // end namespace llvm

llvm/trunk/lib/Support/Windows/Path.inc

 //===----------------------------------------------------------------------===//
 //=== WARNING: Implementation here must contain only generic Windows code that
 //===          is guaranteed to work on *all* Windows variants.
 //===----------------------------------------------------------------------===//
 
 #include "llvm/ADT/STLExtras.h"
 #include <fcntl.h>
 #include <io.h>
+#include <shlobj.h>
 #include <sys/stat.h>
 #include <sys/types.h>
 
 // The Windows.h header must be the last one included.
 #include "Windows.h"
 
 #undef max
 
if (FD == -1) {
     return windows_error::invalid_handle;
   }
 
   ResultFD = FD;
   return error_code::success();
 }
 } // end namespace fs
 
+namespace path {
+
+bool home_directory(SmallVectorImpl<char> &result) {
+  wchar_t Path[MAX_PATH];
+  if (::SHGetFolderPathW(0, CSIDL_APPDATA | CSIDL_FLAG_CREATE, 0,
+                         SHGFP_TYPE_CURRENT, Path) != S_OK)
+    return false;
+
+  if (UTF16ToUTF8(Path, ::wcslen(Path), result))
+    return false;
+
+  return true;
+}
+
+} // end namespace path
+
 namespace windows {
 llvm::error_code UTF8ToUTF16(llvm::StringRef utf8,
                              llvm::SmallVectorImpl<wchar_t> &utf16) {
   int len = ::MultiByteToWideChar(CP_UTF8, MB_ERR_INVALID_CHARS,
                                   utf8.begin(), utf8.size(),
                                   utf16.begin(), 0);
 
   if (len == 0)

llvm/trunk/unittests/Support/Path.cpp

TEST(Support, AbsolutePathIteratorWin32) {
   ASSERT_EQ(ExpectedPathComponents.size(), ActualPathComponents.size());
 
   for (size_t i = 0; i <ExpectedPathComponents.size(); ++i) {
     EXPECT_EQ(ExpectedPathComponents[i].str(), ActualPathComponents[i].str());
   }
 }
 #endif // LLVM_ON_WIN32
 
+TEST(Support, HomeDirectory) {
+#ifdef LLVM_ON_UNIX
+  // This test only makes sense on Unix if $HOME is set.
+  if (::getenv("HOME")) {
+#endif
+    SmallString<128> HomeDir;
+    EXPECT_TRUE(path::home_directory(HomeDir));
+    EXPECT_FALSE(HomeDir.empty());
+#ifdef LLVM_ON_UNIX
+  }
+#endif
+}
+
 class FileSystemTest : public testing::Test {
 protected:
   /// Unique temporary directory in which all created filesystem entities must
   /// be placed. It is recursively removed at the end of each test.
   SmallString<128> TestDirectory;
 
   virtual void SetUp() {
     ASSERT_NO_ERROR(