[clang-tools-extra] reapply [clang-doc] Add --asset option to clang-doc (PR #96358)

[via cfe-commits]

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@@ -127,16 +133,86 @@ std::string getFormatString() {
 // GetMainExecutable (since some platforms don't support taking the
 // address of main, and some platforms can't implement GetMainExecutable
 // without being given the address of a function in the main executable).
-std::string GetExecutablePath(const char *Argv0, void *MainAddr) {
+std::string getExecutablePath(const char *Argv0, void *MainAddr) {
   return llvm::sys::fs::getMainExecutable(Argv0, MainAddr);
 }
 
+llvm::Error getAssetFiles(clang::doc::ClangDocContext &CDCtx) {
+  using DirIt = llvm::sys::fs::directory_iterator;
+  std::error_code FileErr;
+  llvm::SmallString<128> FilePath(UserAssetPath);
+  for (DirIt DirStart = DirIt(UserAssetPath, FileErr),
+                   DirEnd;
+       !FileErr && DirStart != DirEnd; DirStart.increment(FileErr)) {
+    FilePath = DirStart->path();
+    if (llvm::sys::fs::is_regular_file(FilePath)) {
+      if (llvm::sys::path::extension(FilePath) == ".css")
+        CDCtx.UserStylesheets.insert(CDCtx.UserStylesheets.begin(),
+                                     std::string(FilePath));
+      else if (llvm::sys::path::extension(FilePath) == ".js")
+        CDCtx.FilesToCopy.emplace_back(FilePath.str());
+    }
+  }
+  if (FileErr)
+    return llvm::createFileError(FilePath, FileErr);
+  return llvm::Error::success();
+}
+
+llvm::Error getDefaultAssetFiles(const char *Argv0,
+                                 clang::doc::ClangDocContext &CDCtx) {
+  void *MainAddr = (void *)(intptr_t)getExecutablePath;
+  std::string ClangDocPath = getExecutablePath(Argv0, MainAddr);
+  llvm::SmallString<128> NativeClangDocPath;
+  llvm::sys::path::native(ClangDocPath, NativeClangDocPath);
+
+  llvm::SmallString<128> AssetsPath;
+  AssetsPath = llvm::sys::path::parent_path(NativeClangDocPath);
+  llvm::sys::path::append(AssetsPath, "..", "share", "clang");
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PeterChou1 wrote:

I've modify the pr to change where clang-doc keeps the install file 

https://github.com/llvm/llvm-project/pull/96358