From 842894d1c680ab7cf6e03eb31150f26740ae2d02 Mon Sep 17 00:00:00 2001
From: Anthony Cui <anthonycui@google.com>
Date: Wed, 24 Jul 2024 13:32:41 -0700
Subject: [PATCH] Generate necessary config files for the Clang tool on the Go
 side.

PiperOrigin-RevId: 655682520
---
 tools/nvidia_driver_differ/parser/BUILD       |  5 +-
 .../parser/clang_config.go                    | 58 +++++++++++++++++++
 .../parser/json_definitions.go                |  2 +-
 3 files changed, 63 insertions(+), 2 deletions(-)
 create mode 100644 tools/nvidia_driver_differ/parser/clang_config.go

diff --git a/tools/nvidia_driver_differ/parser/BUILD b/tools/nvidia_driver_differ/parser/BUILD
index 2c09c1195..04c6c9b8a 100644
--- a/tools/nvidia_driver_differ/parser/BUILD
+++ b/tools/nvidia_driver_differ/parser/BUILD
@@ -7,7 +7,10 @@ package(
 
 go_library(
     name = "parser",
-    srcs = ["json_definitions.go"],
+    srcs = [
+        "clang_config.go",
+        "json_definitions.go",
+    ],
     visibility = ["//tools/nvidia_driver_differ:__subpackages__"],
     deps = ["@com_github_google_go_cmp//cmp:go_default_library"],
 )
diff --git a/tools/nvidia_driver_differ/parser/clang_config.go b/tools/nvidia_driver_differ/parser/clang_config.go
new file mode 100644
index 000000000..675d90342
--- /dev/null
+++ b/tools/nvidia_driver_differ/parser/clang_config.go
@@ -0,0 +1,58 @@
+// Copyright 2024 The gVisor Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package parser
+
+import (
+	"encoding/json"
+	"fmt"
+	"os"
+)
+
+// ClangASTConfig is the format for compilation_commands.json.
+type ClangASTConfig struct {
+	Directory string   `json:"directory"`
+	Arguments []string `json:"arguments"`
+	Filename  string   `json:"file"`
+}
+
+// NewParserConfig creates a ClangASTConfig for the given file using the list of includes.
+func NewParserConfig(directory, filename string, includes []string) ClangASTConfig {
+	args := []string{"clang"}
+	for _, include := range includes {
+		args = append(args, "-I", include)
+	}
+	args = append(args, filename)
+
+	return ClangASTConfig{
+		Directory: directory,
+		Arguments: args,
+		Filename:  filename,
+	}
+}
+
+// CreateCompileCommandsFile writes the given config to file.
+func CreateCompileCommandsFile(config []ClangASTConfig, path string) error {
+	f, err := os.Create(path)
+	if err != nil {
+		return fmt.Errorf("failed to create %s: %w", path, err)
+	}
+	defer f.Close()
+
+	if err := json.NewEncoder(f).Encode(config); err != nil {
+		return fmt.Errorf("failed to write config to file: %w", err)
+	}
+
+	return nil
+}
diff --git a/tools/nvidia_driver_differ/parser/json_definitions.go b/tools/nvidia_driver_differ/parser/json_definitions.go
index 1d12e6eb2..e7e1d92a0 100644
--- a/tools/nvidia_driver_differ/parser/json_definitions.go
+++ b/tools/nvidia_driver_differ/parser/json_definitions.go
@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-// Package parser contains functions for parsing the output of driver_ast_parser.
+// Package parser contains functions for interfacing with driver_ast_parser.
 package parser
 
 import (