Minimalistic systemd service

debian/control

@@ -2,7 +2,7 @@ Source: rmrf
 Section: mail
 Priority: optional
 Maintainer: Benny Baumann <benbe@chaotikum.org>
-Build-Depends: debhelper (>= 10), libncurses-dev (>=6) | libncurses5-dev (>=6), libssl-dev (>= 1.1.0), libboost-dev, libboost-test-dev, libpython3-dev, liblua5.3-dev, gettext
+Build-Depends: debhelper (>= 10), libncurses-dev (>=6) | libncurses5-dev (>=6), libssl-dev (>= 1.1.0), libboost-dev, libboost-test-dev, libpython3-dev, liblua5.3-dev, libsystemd-dev (>= 42), gettext
 Standards-Version: 4.1.2
 Homepage: https://git.chaotikum.org/ReadMailReallyFast
 Vcs-Git: https://git.chaotikum.org/ReadMailReallyFast/code.git

src/app/mumta.cpp

+#include <chrono>
+#include <cstdint>
+#include <thread>
+
+#include "service/daemonctl.hpp"
+
+int main() {
+    dctl_status_msg("Initializing");
+    dctl_status_msg("Reading configuration");
+    dctl_status_msg("Initializing network");
+    dctl_status_msg("Loading caches");
+    dctl_status_msg("Refreshing caches");
+    dctl_status_msg("Reading state");
+    dctl_status_msg("Initializing");
+    dctl_status_msg("Binding sockets");
+
+    dctl_status_msg("Activating");
+    dctl_status_ready();
+    dctl_status_msg("Active");
+
+    for(size_t x = 10; x; x--) {
+        std::this_thread::sleep_for(std::chrono::seconds(1));
+        dctl_watchdog_refresh();
+    }
+
+    dctl_status_msg("Preparing for shutdown");
+    dctl_status_shutdown();
+    dctl_status_msg("Finalizing pending transactions");
+    dctl_status_msg("Storing active state");
+    dctl_status_msg("Storing active caches");
+    dctl_status_msg("Closing active sockets");
+    dctl_status_msg("Inactive");
+}

src/app/mumta.ldflags

+`pkg-config --cflags --libs libsystemd`

src/macros.hpp

+#pragma once
+
+#define ATTR_NONNULL_ALL __attribute__((nonnull))
+#define ATTR_NONNULL(...) __attribute__((nonnull(__VA_ARGS__)))
+
+#define ATTR_PRINTF(fmtpos, argpos) __attribute__(( format(printf, (fmtpos), (argpos) ) ))
+#define ATTR_STRFTIME(fmtpos) __attribute__(( format(strftime, (fmtpos), 0 ) ))
+
+#define ATTR_PACKED __attribute__((packed))
+
+#define ATTR_WEAK __attribute__((weak))
+
+#define ATTR_LIKELY(x) __builtin_expect((x), 1)
+#define ATTR_UNLIKELY(x) __builtin_expect((x), 0)

src/service/daemonctl.hpp

+#pragma once
+
+#include "macros.hpp"
+
+ATTR_NONNULL_ALL
+void dctl_status_msg(const char* msg);
+
+void dctl_status_ready();
+void dctl_status_reload();
+void dctl_status_shutdown();
+
+void dctl_watchdog_refresh();

src/service/daemonctl_rcd.cpp

+#include "service/daemonctl.hpp"
+
+#ifdef __FreeBSD__
+
+ATTR_WEAK
+void dctl_status_msg(const char* msg) {
+    (void)msg;
+}
+
+ATTR_WEAK
+void dctl_status_ready() {
+
+}
+
+ATTR_WEAK
+void dctl_status_reload() {
+
+}
+
+ATTR_WEAK
+void dctl_status_shutdown() {
+
+}
+
+ATTR_WEAK
+void dctl_watchdog_refresh() {
+
+}
+
+#endif

src/service/daemonctl_systemd.cpp

+#include "service/daemonctl.hpp"
+
+#ifdef __linux__
+
+#include <systemd/sd-daemon.h>
+
+#include <iostream>
+
+ATTR_NONNULL_ALL
+void dctl_status_msg(const char* msg) {
+    sd_notifyf(0, "STATUS=%s", msg);
+    std::cout << SD_INFO << "STATUS=" << msg << std::endl;
+}
+
+void dctl_status_ready() {
+    sd_notify(0, "READY=1");
+}
+
+void dctl_status_reload() {
+    sd_notify(0, "RELOADING=1");
+}
+
+void dctl_status_shutdown() {
+    sd_notify(0, "STOPPING=1");
+}
+
+void dctl_watchdog_refresh() {
+    sd_notify(0, "WATCHDOG=1");
+}
+
+#endif