Keep configuration file search directories in ExpansionContext. NFC

Class ExpansionContext encapsulates options for search and expansion of
response files, including configuration files. With this change the
directories which are searched for configuration files are also stored
in ExpansionContext.

Differential Revision: https://reviews.llvm.org/D135439

1 files changed, 37 insertions, 0 deletions

diff --git a/llvm/lib/Support/CommandLine.cpp b/llvm/lib/Support/CommandLine.cpp
index 899cc52..3986c91 100644
--- a/llvm/lib/Support/CommandLine.cpp
+++ b/llvm/lib/Support/CommandLine.cpp
@@ -1350,6 +1350,43 @@ bool cl::expandResponseFiles(int Argc, const char *const *Argv,
 ExpansionContext::ExpansionContext(BumpPtrAllocator &A, TokenizerCallback T)
     : Saver(A), Tokenizer(T), FS(vfs::getRealFileSystem().get()) {}
 
+bool ExpansionContext::findConfigFile(StringRef FileName,
+                                      SmallVectorImpl<char> &FilePath) {
+  SmallString<128> CfgFilePath;
+  const auto FileExists = [this](SmallString<128> Path) -> bool {
+    auto Status = FS->status(Path);
+    return Status &&
+           Status->getType() == llvm::sys::fs::file_type::regular_file;
+  };
+
+  // If file name contains directory separator, treat it as a path to
+  // configuration file.
+  if (llvm::sys::path::has_parent_path(FileName)) {
+    CfgFilePath = FileName;
+    if (llvm::sys::path::is_relative(FileName) && FS->makeAbsolute(CfgFilePath))
+      return false;
+    if (!FileExists(CfgFilePath))
+      return false;
+    FilePath.assign(CfgFilePath.begin(), CfgFilePath.end());
+    return true;
+  }
+
+  // Look for the file in search directories.
+  for (const StringRef &Dir : SearchDirs) {
+    if (Dir.empty())
+      continue;
+    CfgFilePath.assign(Dir);
+    llvm::sys::path::append(CfgFilePath, FileName);
+    llvm::sys::path::native(CfgFilePath);
+    if (FileExists(CfgFilePath)) {
+      FilePath.assign(CfgFilePath.begin(), CfgFilePath.end());
+      return true;
+    }
+  }
+
+  return false;
+}
+
 bool ExpansionContext::readConfigFile(StringRef CfgFile,
                                       SmallVectorImpl<const char *> &Argv) {
   SmallString<128> AbsPath;