improve alloc stats interface; fix admin command formatting

Signed-off-by: Jason Volk <jason@zemos.net>

src/admin/debug/commands.rs

@@ -632,12 +632,12 @@ pub(super) async fn resolve_true_destination(
 pub(super) fn memory_stats() -> RoomMessageEventContent {
 	let html_body = conduit::alloc::memory_stats();
 
-	if html_body.is_empty() {
+	if html_body.is_none() {
 		return RoomMessageEventContent::text_plain("malloc stats are not supported on your compiled malloc.");
 	}
 
 	RoomMessageEventContent::text_html(
 		"This command's output can only be viewed by clients that render HTML.".to_owned(),
-		html_body,
+		html_body.expect("string result"),
 	)
 }

src/admin/server/commands.rs

@@ -20,17 +20,12 @@ pub(super) async fn show_config(_body: Vec<&str>) -> Result<RoomMessageEventCont
 }
 
 pub(super) async fn memory_usage(_body: Vec<&str>) -> Result<RoomMessageEventContent> {
-	let response0 = services().memory_usage().await?;
-	let response1 = services().db.db.memory_usage()?;
-	let response2 = conduit::alloc::memory_usage();
+	let services_usage = services().memory_usage().await?;
+	let database_usage = services().db.db.memory_usage()?;
+	let allocator_usage = conduit::alloc::memory_usage().map_or(String::new(), |s| format!("\nAllocator:\n{s}"));
 
 	Ok(RoomMessageEventContent::text_plain(format!(
-		"Services:\n{response0}\nDatabase:\n{response1}\n{}",
-		if !response2.is_empty() {
-			format!("Allocator:\n {response2}")
-		} else {
-			String::new()
-		}
+		"Services:\n{services_usage}\nDatabase:\n{database_usage}{allocator_usage}",
 	)))
 }
 

src/core/alloc/default.rs

@@ -1,9 +1,9 @@
 //! Default allocator with no special features
 
-/// Always returns the empty string
+/// Always returns None
 #[must_use]
-pub fn memory_stats() -> String { String::default() }
+pub fn memory_stats() -> Option<String> { None }
 
-/// Always returns the empty string
+/// Always returns None
 #[must_use]
-pub fn memory_usage() -> String { String::default() }
+pub fn memory_usage() -> Option<String> { None }

src/core/alloc/hardened.rs

@@ -4,9 +4,10 @@
 static HMALLOC: hardened_malloc_rs::HardenedMalloc = hardened_malloc_rs::HardenedMalloc;
 
 #[must_use]
-pub fn memory_usage() -> String {
-	String::default() //TODO: get usage
-}
+//TODO: get usage
+pub fn memory_usage() -> Option<string> { None }
 
 #[must_use]
-pub fn memory_stats() -> String { "Extended statistics are not available from hardened_malloc.".to_owned() }
+pub fn memory_stats() -> Option<String> {
+	Some("Extended statistics are not available from hardened_malloc.".to_owned())
+}

src/core/alloc/je.rs

@@ -10,7 +10,7 @@ use tikv_jemallocator as jemalloc;
 static JEMALLOC: jemalloc::Jemalloc = jemalloc::Jemalloc;
 
 #[must_use]
-pub fn memory_usage() -> String {
+pub fn memory_usage() -> Option<String> {
 	use mallctl::stats;
 
 	let mibs = |input: Result<usize, mallctl::Error>| {
@@ -27,14 +27,14 @@ pub fn memory_usage() -> String {
 	let metadata = mibs(stats::metadata::read());
 	let resident = mibs(stats::resident::read());
 	let retained = mibs(stats::retained::read());
-	format!(
+	Some(format!(
 		"allocated: {allocated:.2} MiB\nactive: {active:.2} MiB\nmapped: {mapped:.2} MiB\nmetadata: {metadata:.2} \
 		 MiB\nresident: {resident:.2} MiB\nretained: {retained:.2} MiB\n"
-	)
+	))
 }
 
 #[must_use]
-pub fn memory_stats() -> String {
+pub fn memory_stats() -> Option<String> {
 	const MAX_LENGTH: usize = 65536 - 4096;
 
 	let opts_s = "d";
@@ -51,7 +51,7 @@ pub fn memory_stats() -> String {
 	unsafe { ffi::malloc_stats_print(Some(malloc_stats_cb), opaque, opts_p) };
 
 	str.truncate(MAX_LENGTH);
-	format!("<pre><code>{str}</code></pre>")
+	Some(format!("<pre><code>{str}</code></pre>"))
 }
 
 extern "C" fn malloc_stats_cb(opaque: *mut c_void, msg: *const c_char) {