From f38bad630946766734b50cbd48139f9ba52bcf8d Mon Sep 17 00:00:00 2001
From: Catsayer <ci.90@proton.me>
Date: Sat, 6 Dec 2025 16:10:19 +0800
Subject: [PATCH]   Add mutex protection for projects map in API

  The projects map in the API struct was missing concurrency protection
  while other maps (files, symbols, types) were already protected by
  mutexes. This inconsistency could lead to race conditions if the API
  is used concurrently in the future.

  Changes:
  - Add sync.RWMutex to protect projects map
  - Use RLock/RUnlock for read operations (GetSymbolAtPosition,
    GetSymbolAtLocation, GetTypeOfSymbol, GetSourceFile)
  - Use Lock/Unlock for write operations (LoadProject, releaseHandle)

  This change maintains consistency with existing code patterns and
  prepares the codebase for potential concurrent request handling.

  Author: Catsayer
---
 internal/api/api.go | 34 +++++++++++++++++++++++++++-------
 1 file changed, 27 insertions(+), 7 deletions(-)

diff --git a/internal/api/api.go b/internal/api/api.go
index 2c4fa079ac..41a478074d 100644
--- a/internal/api/api.go
+++ b/internal/api/api.go
@@ -32,13 +32,14 @@ type API struct {
 	logger  logging.Logger
 	session *project.Session
 
-	projects  map[Handle[project.Project]]tspath.Path
-	filesMu   sync.Mutex
-	files     handleMap[ast.SourceFile]
-	symbolsMu sync.Mutex
-	symbols   handleMap[ast.Symbol]
-	typesMu   sync.Mutex
-	types     handleMap[checker.Type]
+	projectsMu sync.RWMutex
+	projects   map[Handle[project.Project]]tspath.Path
+	filesMu    sync.Mutex
+	files      handleMap[ast.SourceFile]
+	symbolsMu  sync.Mutex
+	symbols    handleMap[ast.Symbol]
+	typesMu    sync.Mutex
+	types      handleMap[checker.Type]
 }
 
 func NewAPI(init *APIInit) *API {
@@ -145,12 +146,18 @@ func (api *API) LoadProject(ctx context.Context, configFileName string) (*Projec
 		return nil, err
 	}
 	data := NewProjectResponse(project)
+	// Acquire write lock to safely add project to the map
+	api.projectsMu.Lock()
 	api.projects[data.Id] = project.ConfigFilePath()
+	api.projectsMu.Unlock()
 	return data, nil
 }
 
 func (api *API) GetSymbolAtPosition(ctx context.Context, projectId Handle[project.Project], fileName string, position int) (*SymbolResponse, error) {
+	// Acquire read lock to safely access projects map
+	api.projectsMu.RLock()
 	projectPath, ok := api.projects[projectId]
+	api.projectsMu.RUnlock()
 	if !ok {
 		return nil, errors.New("project ID not found")
 	}
@@ -174,7 +181,10 @@ func (api *API) GetSymbolAtPosition(ctx context.Context, projectId Handle[projec
 }
 
 func (api *API) GetSymbolAtLocation(ctx context.Context, projectId Handle[project.Project], location Handle[ast.Node]) (*SymbolResponse, error) {
+	// Acquire read lock to safely access projects map
+	api.projectsMu.RLock()
 	projectPath, ok := api.projects[projectId]
+	api.projectsMu.RUnlock()
 	if !ok {
 		return nil, errors.New("project ID not found")
 	}
@@ -216,7 +226,10 @@ func (api *API) GetSymbolAtLocation(ctx context.Context, projectId Handle[projec
 }
 
 func (api *API) GetTypeOfSymbol(ctx context.Context, projectId Handle[project.Project], symbolHandle Handle[ast.Symbol]) (*TypeResponse, error) {
+	// Acquire read lock to safely access projects map
+	api.projectsMu.RLock()
 	projectPath, ok := api.projects[projectId]
+	api.projectsMu.RUnlock()
 	if !ok {
 		return nil, errors.New("project ID not found")
 	}
@@ -242,7 +255,10 @@ func (api *API) GetTypeOfSymbol(ctx context.Context, projectId Handle[project.Pr
 }
 
 func (api *API) GetSourceFile(projectId Handle[project.Project], fileName string) (*ast.SourceFile, error) {
+	// Acquire read lock to safely access projects map
+	api.projectsMu.RLock()
 	projectPath, ok := api.projects[projectId]
+	api.projectsMu.RUnlock()
 	if !ok {
 		return nil, errors.New("project ID not found")
 	}
@@ -267,11 +283,15 @@ func (api *API) releaseHandle(handle string) error {
 	switch handle[0] {
 	case handlePrefixProject:
 		projectId := Handle[project.Project](handle)
+		// Acquire write lock to safely delete project from the map
+		api.projectsMu.Lock()
 		_, ok := api.projects[projectId]
 		if !ok {
+			api.projectsMu.Unlock()
 			return fmt.Errorf("project %q not found", handle)
 		}
 		delete(api.projects, projectId)
+		api.projectsMu.Unlock()
 	case handlePrefixFile:
 		fileId := Handle[ast.SourceFile](handle)
 		api.filesMu.Lock()