1. Make resource dir unique and global.

2. Use our custom CDB loader.

include/Compiler/Command.h

@@ -0,0 +1,19 @@
+#pragma once
+
+#include "Clang.h"
+
+namespace clice {
+
+/// Processes and adjusts a raw compile command from compile_commands.json.
+///
+/// This function tokenizes the input command, removes unnecessary arguments,
+/// and ensures the resulting format is suitable for execution.
+///
+/// @param command The raw shell-escaped compile command.
+/// @param out A vector to hold pointers to the processed arguments.
+/// @param buffer A storage buffer for the actual argument strings.
+llvm::Error mangleCommand(llvm::StringRef command,
+                          llvm::SmallVectorImpl<const char*>& out,
+                          llvm::SmallVectorImpl<char>& buffer);
+
+}  // namespace clice

include/Compiler/Compiler.h

@@ -129,11 +129,17 @@ struct PCMInfo {
 };
 
 struct CompliationParams {
+    /// Source file content.
+    llvm::StringRef content;
+
     /// Source file path.
     llvm::SmallString<128> srcPath;
 
-    /// Source file content.
-    llvm::StringRef content;
+    /// Output file path.
+    llvm::SmallString<128> outPath;
+
+    /// Responsible for storing the arguments.
+    llvm::SmallString<1024> command;
 
     /// - If we are building PCH, we need a size to verify the bounds of preamble. That is
     /// which source code range the PCH will cover.
@@ -148,12 +154,6 @@ struct CompliationParams {
     /// - If the header is not empty, the preprocessor must be executed to compute the bounds.
     void computeBounds(llvm::StringRef header = "");
 
-    /// Command line arguments.
-    llvm::ArrayRef<const char*> args;
-
-    /// Output file path.
-    llvm::SmallString<128> outPath;
-
     llvm::IntrusiveRefCntPtr<vfs::FileSystem> vfs = new ThreadSafeFS();
 
     /// Information about reuse PCH.

include/Server/Command.h

@@ -9,9 +9,16 @@ class CommandManager {
 public:
     void update(llvm::StringRef dir);
 
-    std::vector<std::string> lookup(llvm::StringRef file);
+    /// Return the commands of first meet file.
+    llvm::StringRef lookupFirst(llvm::StringRef file);
+
+    llvm::ArrayRef<std::string> lookup(llvm::StringRef file);
+
 private:
-    llvm::StringMap<std::unique_ptr<clang::tooling::CompilationDatabase>> CDBs;
+    /// CDB file -> file -> [commands]
+    using Commands = std::vector<std::string>;
+    using CDB = llvm::StringMap<Commands>;
+    llvm::StringMap<CDB> CDBs;
 };
 
 }  // namespace clice

include/Server/Scheduler.h

@@ -73,7 +73,7 @@ class Scheduler {
 private:
     async::promise<void> updatePCH(llvm::StringRef path,
                                    llvm::StringRef content,
-                                   llvm::ArrayRef<const char*> args);
+                                   llvm::StringRef command);
 
     async::promise<void> updatePCM() {
         co_return;

include/Support/FileSystem.h

@@ -7,10 +7,31 @@
 
 namespace clice {
 
-namespace vfs = llvm::vfs;
-namespace fs = llvm::sys::fs;
 namespace path = llvm::sys::path;
 
+namespace fs {
+
+using namespace llvm::sys::fs;
+
+inline std::string resource_dir = "";
+
+inline llvm::Error init_resource_dir(llvm::StringRef execute) {
+    llvm::SmallString<128> path;
+    path::append(path, path::parent_path(execute), "..");
+    path::append(path, "lib", "clang", "20");
+
+    if(auto error = real_path(path, path)) {
+        return llvm::make_error<llvm::StringError>(error.message(), error);
+    }
+
+    resource_dir = path.str();
+    return llvm::Error::success();
+}
+
+}  // namespace fs
+
+namespace vfs = llvm::vfs;
+
 class ThreadSafeFS : public vfs::ProxyFileSystem {
 public:
     explicit ThreadSafeFS() : ProxyFileSystem(vfs::createPhysicalFileSystem()) {}