Perform wildcard expansion in Process::GetArgumentVector on Windows (PR17098)

On Windows, wildcard expansion isn't performed by the shell, but left to the
program itself. The common way to do this is to link with setargv.obj, which
performs the expansion on argc/argv before main is entered. However, we don't
use argv in Clang on Windows, but instead call GetCommandLineW so we can handle
unicode arguments. This means we have to do wildcard expansion ourselves.

A test case will be added on the Clang side.

Differential Revision: http://reviews.llvm.org/D4529

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213114 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Support/Windows/Process.inc

@@ -183,37 +183,89 @@ static std::error_code windows_error(DWORD E) {
   return mapWindowsError(E);
 }
 
+static void AllocateAndPush(const SmallVectorImpl<char> &S,
+                            SmallVectorImpl<const char *> &Vector,
+                            SpecificBumpPtrAllocator<char> &Allocator) {
+  char *Buffer = Allocator.Allocate(S.size() + 1);
+  ::memcpy(Buffer, S.data(), S.size());
+  Buffer[S.size()] = '\0';
+  Vector.push_back(Buffer);
+}
+
+/// Convert Arg from UTF-16 to UTF-8 and push it onto Args.
+static std::error_code
+ConvertAndPushArg(const wchar_t *Arg, SmallVectorImpl<const char *> &Args,
+                  SpecificBumpPtrAllocator<char> &Allocator) {
+  SmallVector<char, MAX_PATH> ArgString;
+  if (std::error_code ec = windows::UTF16ToUTF8(Arg, wcslen(Arg), ArgString))
+    return ec;
+  AllocateAndPush(ArgString, Args, Allocator);
+  return std::error_code();
+}
+
+/// \brief Perform wildcard expansion of Arg, or just push it into Args if it
+/// doesn't have wildcards or doesn't match any files.
+static std::error_code
+WildcardExpand(const wchar_t *Arg, SmallVectorImpl<const char *> &Args,
+               SpecificBumpPtrAllocator<char> &Allocator) {
+  if (!wcspbrk(Arg, L"*?")) {
+    // Arg does not contain any wildcard characters. This is the common case.
+    return ConvertAndPushArg(Arg, Args, Allocator);
+  }
+
+  // Extract any directory part of the argument.
+  SmallVector<char, MAX_PATH> Dir;
+  if (std::error_code ec = windows::UTF16ToUTF8(Arg, wcslen(Arg), Dir))
+    return ec;
+  sys::path::remove_filename(Dir);
+  const int DirSize = Dir.size();
+
+  // Search for matching files.
+  WIN32_FIND_DATAW FileData;
+  HANDLE FindHandle = FindFirstFileW(Arg, &FileData);
+  if (FindHandle == INVALID_HANDLE_VALUE) {
+    return ConvertAndPushArg(Arg, Args, Allocator);
+  }
+
+  std::error_code ec;
+  do {
+    SmallVector<char, MAX_PATH> FileName;
+    ec = windows::UTF16ToUTF8(FileData.cFileName, wcslen(FileData.cFileName),
+                              FileName);
+    if (ec)
+      break;
+
+    // Push the filename onto Dir, and remove it afterwards.
+    llvm::sys::path::append(Dir, StringRef(FileName.data(), FileName.size()));
+    AllocateAndPush(Dir, Args, Allocator);
+    Dir.resize(DirSize);
+  } while (FindNextFileW(FindHandle, &FileData));
+
+  FindClose(FindHandle);
+  return ec;
+}
+
 std::error_code
 Process::GetArgumentVector(SmallVectorImpl<const char *> &Args,
                            ArrayRef<const char *>,
                            SpecificBumpPtrAllocator<char> &ArgAllocator) {
-  int NewArgCount;
-  std::error_code ec;
-
-  wchar_t **UnicodeCommandLine = CommandLineToArgvW(GetCommandLineW(),
-                                                    &NewArgCount);
+  int ArgCount;
+  wchar_t **UnicodeCommandLine =
+      CommandLineToArgvW(GetCommandLineW(), &ArgCount);
   if (!UnicodeCommandLine)
     return windows_error(::GetLastError());
 
-  Args.reserve(NewArgCount);
+  Args.reserve(ArgCount);
+  std::error_code ec;
 
-  for (int i = 0; i < NewArgCount; ++i) {
-    SmallVector<char, MAX_PATH> NewArgString;
-    ec = windows::UTF16ToUTF8(UnicodeCommandLine[i],
-                              wcslen(UnicodeCommandLine[i]),
-                              NewArgString);
+  for (int i = 0; i < ArgCount; ++i) {
+    ec = WildcardExpand(UnicodeCommandLine[i], Args, ArgAllocator);
     if (ec)
       break;
-
-    char *Buffer = ArgAllocator.Allocate(NewArgString.size() + 1);
-    ::memcpy(Buffer, NewArgString.data(), NewArgString.size() + 1);
-    Args.push_back(Buffer);
   }
-  LocalFree(UnicodeCommandLine);
-  if (ec)
-    return ec;
 
-  return std::error_code();
+  LocalFree(UnicodeCommandLine);
+  return ec;
 }
 
 bool Process::StandardInIsUserInput() {