localPackages.hpcstat: add lock only when connect to db

flake.nix

@@ -147,7 +147,7 @@
           buildInputs = [ pkgs.clang-tools_18 ];
           CMAKE_EXPORT_COMPILE_COMMANDS = "1";
         };
-        hpcstat = pkgs.mkShell
+        hpcstat = pkgs.mkShell.override { stdenv = pkgs.gcc14Stdenv; }
         {
           inputsFrom = [ (inputs.self.packages.x86_64-linux.hpcstat.override { version = null; }) ];
           packages = [ pkgs.clang-tools_18 ];

local/pkgs/default.nix

@@ -69,7 +69,8 @@ inputs: rec
     { src = inputs.topInputs.kylin-virtual-keyboard; };
   biu = inputs.pkgs.callPackage ./biu { inherit nameof zpp-bits; };
   zxorm = inputs.pkgs.callPackage ./zxorm { src = inputs.topInputs.zxorm; };
-  hpcstat = inputs.pkgs.callPackage ./hpcstat { inherit nameof sqlite-orm zpp-bits date biu openxlsx; };
+  hpcstat = inputs.pkgs.callPackage ./hpcstat
+    { inherit nameof sqlite-orm zpp-bits date biu openxlsx; stdenv = inputs.pkgs.gcc14Stdenv; };
   openxlsx = inputs.pkgs.callPackage ./openxlsx { src = inputs.topInputs.openxlsx; };
   sqlite-orm = inputs.pkgs.callPackage ./sqlite-orm { src = inputs.topInputs.sqlite-orm; };
   mkPnpmPackage = inputs.pkgs.callPackage ./mkPnpmPackage.nix {};

local/pkgs/hpcstat/.clangd

@@ -1,3 +1,3 @@
 CompileFlags:
-  Add: [ -Wall, -Wextra, -std=c++23 ]
+  Add: [ -Wall, -Wextra, -std=c++26 ]
   Compiler: g++

local/pkgs/hpcstat/CMakeLists.txt

@@ -1,4 +1,5 @@
-cmake_minimum_required(VERSION 3.14)
+# cmake_minimum_required(VERSION 3.30)
+cmake_minimum_required(VERSION 3.29)
 project(hpcstat VERSION 0.0.0 LANGUAGES CXX)
 enable_testing()
 include(GNUInstallDirs)
@@ -25,7 +26,8 @@ find_package(OpenXLSX REQUIRED)
 
 add_executable(hpcstat src/main.cpp src/env.cpp src/keys.cpp src/ssh.cpp src/sql.cpp src/lfs.cpp src/common.cpp
   src/push.cpp src/disk.cpp)
-target_compile_features(hpcstat PRIVATE cxx_std_23)
+# target_compile_features(hpcstat PRIVATE cxx_std_26)
+target_compile_options(hpcstat PRIVATE "-std=c++26")
 target_include_directories(hpcstat PRIVATE ${PROJECT_SOURCE_DIR}/include ${ZPP_BITS_INCLUDE_DIR})
 target_link_libraries(hpcstat PRIVATE Boost::headers Boost::filesystem sqlite_orm::sqlite_orm
   nlohmann_json::nlohmann_json range-v3::range-v3 date::date date::date-tz httplib::httplib

local/pkgs/hpcstat/include/hpcstat/common.hpp

@@ -15,7 +15,6 @@
 # include <date/date.h>
 # include <date/tz.h>
 # include <boost/interprocess/sync/file_lock.hpp>
-# include <zpp_bits.h>
 # include <biu.hpp>
 
 namespace hpcstat

local/pkgs/hpcstat/src/main.cpp

@@ -7,7 +7,6 @@
 # include <hpcstat/disk.hpp>
 # include <range/v3/view.hpp>
 # include <boost/exception/diagnostic_information.hpp>
-# include <boost/filesystem.hpp>
 # include <termcolor/termcolor.hpp>
 
 int main(int argc, const char** argv)
@@ -16,10 +15,6 @@ int main(int argc, const char** argv)
   using namespace std::literals;
   try
   {
-    auto lockfile = (boost::filesystem::temp_directory_path() / "hpcstat.lock").string();
-    std::ofstream{lockfile};
-    boost::interprocess::file_lock lock(lockfile.c_str());
-
     std::vector<std::string> args(argv, argv + argc);
 
     if (args.size() == 1)
@@ -27,11 +22,7 @@ int main(int argc, const char** argv)
       std::cout << "Usage: hpcstat initdb|login|logout|submitjob|finishjob|verify|export|version|diskstat\n";
       return 1;
     }
-    else if (args[1] == "initdb")
-    {
-      lock.lock();
-      if (!sql::initdb()) { std::cerr << "Failed to initialize database\n"; return 1; }
-    }
+    else if (args[1] == "initdb") { if (!sql::initdb()) { std::cerr << "Failed to initialize database\n"; return 1; } }
     else if (args[1] == "login")
     {
       if (env::interactive()) std::cout << "Communicating with the agent..." << std::flush;
@@ -50,7 +41,6 @@ int main(int argc, const char** argv)
         auto signature = ssh::sign(biu::serialize<char>(data), *fp);
         if (!signature) return 1;
         data.Signature = *signature;
-        lock.lock();
         sql::writedb(data);
         if (env::interactive())
         {
@@ -88,7 +78,7 @@ int main(int argc, const char** argv)
     {
       if (auto session_id = env::env("XDG_SESSION_ID", true); !session_id)
         return 1;
-      else { lock.lock(); sql::writedb(sql::LogoutData{ .Time = now(), .SessionId = *session_id }); }
+      else sql::writedb(sql::LogoutData{ .Time = now(), .SessionId = *session_id });
     }
     else if (args[1] == "submitjob")
     {
@@ -111,14 +101,12 @@ int main(int argc, const char** argv)
         auto signature = ssh::sign(biu::serialize<char>(data), *fp);
         if (!signature) return 1;
         data.Signature = *signature;
-        lock.lock();
         sql::writedb(data);
         std::cout << "Job <{}> was submitted to <{}> by <{}>.\n"_f(bsub->first, bsub->second, Keys[*fp].Username);
       }
     }
     else if (args[1] == "finishjob")
     {
-      lock.lock();
       if (auto fp = ssh::fingerprint(); !fp) return 1;
       else if (auto session = env::env("XDG_SESSION_ID", true); !session)
         return 1;
@@ -166,12 +154,10 @@ int main(int argc, const char** argv)
       auto begin = sys_seconds(sys_days(month(month_n) / 1 / year_n)).time_since_epoch().count();
       auto end = sys_seconds(sys_days(month(month_n) / 1 / year_n + months(1)))
         .time_since_epoch().count();
-      lock.lock();
       if (!sql::export_data(begin, end, "{}{}.xlsx"_f(year_n, month_n))) return 1;
     }
     else if (args[1] == "push")
     {
-      lock.lock();
       if (auto jobs = sql::check_job_status(); !jobs) return 1;
       else if (!push::push(*jobs)) return 1;
     }

local/pkgs/hpcstat/src/sql.cpp

@@ -8,14 +8,16 @@
 # define SQLITE_ORM_OPTIONAL_SUPPORTED
 # include <sqlite_orm/sqlite_orm.h>
 # include <OpenXLSX.hpp>
+# include <boost/filesystem.hpp>
 
 namespace hpcstat::sql
 {
-  auto connect(std::optional<std::string> dbfile = std::nullopt)
+  auto connect(std::optional<std::string> dbfile = std::nullopt, bool need_lock = true)
   {
-    auto conn = [&]() { return std::make_optional(sqlite_orm::make_storage
+    // a function to actually connecto to db
+    auto conn = [](std::string dbfile) { return std::make_optional(sqlite_orm::make_storage
     (
-      *dbfile,
+      dbfile,
       sqlite_orm::make_table
       (
         "login",
@@ -70,31 +72,52 @@ namespace hpcstat::sql
         sqlite_orm::make_column("status", &CheckJobData::Status)
       )
     ));};
+
+    // a class to take care of lock
+    struct conn_with_lock
+    {
+      // lock should be declared before conn, so that it will be destructed after conn
+      boost::interprocess::file_lock lock;
+      decltype(conn(std::declval<std::string>())) connection;
+    };
+
+    // set default db path
     if (!dbfile)
     {
       if (auto datadir = env::env("HPCSTAT_DATADIR", true); !datadir)
-        return decltype(conn())();
+        return conn_with_lock{};
       else dbfile = std::filesystem::path(*datadir) / "hpcstat.db";
     }
-    auto result = conn();
-    if (!result) std::cerr << "Failed to connect to database.\n";
-    else result->busy_timeout(10000);
-    return result;
+
+    // set file lock
+    auto lockfile = (boost::filesystem::temp_directory_path() / "hpcstat.lock").string();
+    std::ofstream{lockfile};  // create file
+    boost::interprocess::file_lock lock(lockfile.c_str());
+    if (need_lock) lock.lock();
+
+    // try to connect
+    if (auto result = conn(*dbfile); !result)
+      { std::cerr << "Failed to connect to database.\n"; return conn_with_lock{}; }
+    else
+    {
+      result->busy_timeout(10000);
+      return conn_with_lock{std::move(lock), std::move(result)};
+    }
   }
   bool initdb()
   {
-    if (auto conn = connect(); !conn) return false;
+    if (auto [lock, conn] = connect(); !conn) return false;
     else { conn->sync_schema(); return true; }
   }
   bool writedb(auto value)
-    { if (auto conn = connect(); !conn) return false; else { conn->insert(value); return true; } }
+    { if (auto [lock, conn] = connect(); !conn) return false; else { conn->insert(value); return true; } }
   template bool writedb(LoginData);
   template bool writedb(LogoutData);
   template bool writedb(SubmitJobData);
   template bool writedb(FinishJobData);
   std::optional<std::set<unsigned>> finishjob_remove_existed(std::map<unsigned, std::string> jobid_submit_time)
   {
-    if (auto conn = connect(); !conn) return std::nullopt;
+    if (auto [lock, conn] = connect(); !conn) return std::nullopt;
     else
     {
       auto all_job = jobid_submit_time | ranges::views::keys | ranges::to<std::vector<unsigned>>;
@@ -110,7 +133,8 @@ namespace hpcstat::sql
   std::optional<std::vector<std::tuple<std::string, std::string, std::string>>>
     verify(std::string old_db, std::string new_db)
   {
-    auto old_conn = connect(old_db), new_conn = connect(new_db);
+    auto [_, old_conn] = connect(old_db);
+    auto [_, new_conn] = connect(new_db);
     if (!old_conn || !new_conn) { std::cerr << "Failed to connect to database.\n"; return std::nullopt; }
     else
     {
@@ -153,7 +177,8 @@ namespace hpcstat::sql
     }
   }
   // search corresponding job in submit table
-  std::optional<SubmitJobData> search_job_in_submit(auto connection, unsigned job_id, std::string submit_time)
+  std::optional<SubmitJobData> search_job_in_submit
+    (auto connection, unsigned job_id, std::string submit_time)
   {
     std::optional<SubmitJobData> result;
     long submit_date = [&]
@@ -185,7 +210,7 @@ namespace hpcstat::sql
   }
   bool export_data(long start_time, long end_time, std::string filename)
   {
-    if (auto conn = connect(); !conn) return false;
+    if (auto [lock, conn] = connect(); !conn) return false;
     else
     {
       // 对于一个账户的总计
@@ -312,7 +337,7 @@ namespace hpcstat::sql
   std::optional<std::map<unsigned, std::tuple<std::string, std::string, std::string, std::optional<std::string>>>>
     check_job_status()
   {
-    if (auto conn = connect(); !conn) return std::nullopt;
+    if (auto [lock, conn] = connect(); !conn) return std::nullopt;
     else if (auto jobs_current = lfs::bjobs_list(); !jobs_current) return std::nullopt;
     else
     {