windows: start postgres svc if not running

3 files changed, 138 insertions, 0 deletions

diff --git a/src/bot.rs b/src/bot.rs
index 4942c98..b74bf0d 100644
--- a/src/bot.rs
+++ b/src/bot.rs
@@ -364,6 +364,11 @@ fn after_handle(ctx: PoiseContext) -> BoxFuture<()> {
 }
 
 pub async fn run() -> anyhow::Result<()> {
+    #[cfg(all(windows, feature = "windows_autostart_postgres"))]
+    unsafe {
+        crate::windows_util::ensure_postgres_started()?;
+    };
+
     let token = &CONFIG.discord.auth.token;
 
     let sb_config = songbird::Config::default();
diff --git a/src/lib.rs b/src/lib.rs
index 13a93e0..ac56087 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,5 +1,6 @@
 #![feature(try_blocks)]
 #![feature(let_chains)]
+#![feature(maybe_uninit_slice)]
 
 #[cfg(feature = "db")]
 pub mod db;
@@ -20,6 +21,9 @@ pub mod config;
 pub mod log_setup;
 pub mod util;
 
+#[cfg(windows)]
+pub mod windows_util;
+
 pub use crate::{
     config::*,
     util::*,
diff --git a/src/windows_util.rs b/src/windows_util.rs
new file mode 100644
index 0000000..348ea91
--- /dev/null
+++ b/src/windows_util.rs
@@ -0,0 +1,129 @@
+use windows::{
+    core::HSTRING,
+    Win32::{
+        Foundation,
+        System::Services,
+    },
+};
+
+lazy_static::lazy_static! {
+    static ref PSQL_REGEX: regex::Regex = regex::Regex::new(r#"^(?:postgresql|psql|postgres)-.*([\d\.]*)"#).unwrap();
+}
+
+pub unsafe fn ensure_postgres_started() -> windows::core::Result<()> {
+    let sc_manager = Services::OpenSCManagerW(
+        None,
+        None,
+        (Foundation::GENERIC_READ | Foundation::GENERIC_WRITE).0,
+    )?;
+
+    let services = list_services(sc_manager)?;
+
+    let mut psql_services =
+        services.into_iter().filter(|status| PSQL_REGEX.is_match(&status.name)).collect::<Vec<_>>();
+
+    match psql_services.len() {
+        1 => {},
+
+        0 => {
+            log::warn!("unable to identify an installed postgres service");
+        },
+
+        other => {
+            log::warn!("unable to identify postgres service: {other} potential matches found");
+            return Ok(());
+        },
+    }
+
+    let svc = psql_services.remove(0);
+    log::debug!("identified postgres service: {}", svc.name);
+
+    match svc.status.dwCurrentState {
+        Services::SERVICE_RUNNING => {
+            log::info!("postgres was already running, done");
+            return Ok(());
+        },
+
+        Services::SERVICE_START_PENDING => {
+            log::info!("postgres was already in startup, done");
+            return Ok(());
+        },
+
+        _ => {
+            log::info!("postgres is not running: starting it")
+        },
+    }
+
+    let service =
+        Services::OpenServiceW(sc_manager, &HSTRING::from(&svc.name), Services::SERVICE_START)?;
+
+    Services::StartServiceW(service, None)?;
+
+    log::info!("started postgres service");
+
+    Services::CloseServiceHandle(service)?;
+    Services::CloseServiceHandle(sc_manager)?;
+
+    Ok(())
+}
+
+const RESULT_SIZE: usize = size_of::<Services::ENUM_SERVICE_STATUS_PROCESSW>();
+
+pub struct ServiceStatus {
+    pub display_name: String,
+    pub name:         String,
+    pub status:       Services::SERVICE_STATUS_PROCESS,
+}
+
+pub unsafe fn list_services(
+    sc_manager: Services::SC_HANDLE,
+) -> windows::core::Result<Vec<ServiceStatus>> {
+    let mut bytes_needed: u32 = 0;
+    let mut services_returned: u32 = 0;
+    let mut resume = 0;
+
+    let mut svcs = vec![];
+
+    loop {
+        let mut data = [0u8; 256 * 1024];
+
+        let result = Services::EnumServicesStatusExW(
+            sc_manager,
+            Services::SC_ENUM_PROCESS_INFO,
+            Services::SERVICE_WIN32,
+            Services::SERVICE_STATE_ALL,
+            Some(&mut data),
+            &mut bytes_needed as *mut _,
+            &mut services_returned as *mut _,
+            Some(&mut resume),
+            None,
+        );
+
+        if let Err(ref e) = result
+            && e.code() != Foundation::ERROR_MORE_DATA.to_hresult()
+        {
+            return result.map(|_| unreachable!());
+        }
+
+        let data = bytemuck::cast_slice::<u8, [u8; RESULT_SIZE]>(
+            &data[..services_returned as usize * RESULT_SIZE],
+        );
+
+        let elems = data
+            .into_iter()
+            .map(|x| core::mem::transmute::<_, Services::ENUM_SERVICE_STATUS_PROCESSW>(*x))
+            .map(|x| ServiceStatus {
+                display_name: x.lpDisplayName.to_string().unwrap(),
+                name:         x.lpServiceName.to_string().unwrap(),
+                status:       x.ServiceStatusProcess,
+            });
+
+        svcs.extend(elems);
+
+        if result.is_ok() {
+            break;
+        }
+    }
+
+    Ok(svcs)
+}