refactor: reduce macro-generated lines by >70%, and drop tracing

Every `info!`, `warn!` and `error!` call expanded a complete
`tracing::event!` to mirror its message into `tracing` (#6919),
and that mirror made up most of core's macro output, now removed:
it's down from 219k to 54k lines using

    RUSTC_BOOTSTRAP=1 cargo rustc -p deltachat --lib \
        --profile check -- -Zmacro-stats

A warm build and `touch src/lib.rs` with rustc 1.99.0,

    CARGO_INCREMENTAL=0 RUSTC_WRAPPER= /usr/bin/time -v \
        cargo check -p deltachat

takes about a third less time and 0.37 GiB less peak memory,
`cargo build -p deltachat` about a tenth less time and 0.36 GiB less.
The release binary from `nix build .#deltachat-rpc-server-x86_64-linux`
gets 2.7% smaller.

If we want to use tracing events to integrate better with iroh-debugging,
for example when we move to iroh 1.X,
we could introduce some iroh-relevant tracing events in core.

Author: hpk42

Cargo.lock

@@ -104,7 +104,6 @@ astral-tokio-tar = { version = "0.7.0", default-features = false }
 tokio-util = { workspace = true }
 tokio = { workspace = true, features = ["fs", "rt-multi-thread", "macros"] }
 toml = "0.9"
-tracing = "0.1.41"
 url = "2"
 uuid = { version = "1", features = ["serde", "v4"] }
 walkdir = "2.5.0"

Cargo.toml

@@ -76,12 +76,8 @@ impl Accounts {
         Accounts::open(events, dir, writable).await
     }
 
-    /// Get the ID used to log events.
-    ///
-    /// Account manager logs events with ID 0
-    /// which is not used by any accounts.
-    fn get_id(&self) -> u32 {
-        0
+    fn log_info(&self, file: &str, line: u32, msg: String) {
+        self.emit_event(EventType::Info(format!("{file}:{line}: {msg}")));
     }
 
     /// Ensures the accounts directory and config file exist.
@@ -395,11 +391,6 @@ impl Accounts {
                 "Starting background fetch for {n_accounts} accounts."
             )),
         });
-        ::tracing::event!(
-            ::tracing::Level::INFO,
-            account_id = 0,
-            "Starting background fetch for {n_accounts} accounts."
-        );
         let mut set = JoinSet::new();
         for account in accounts {
             set.spawn(async move {
@@ -415,11 +406,6 @@ impl Accounts {
                 "Finished background fetch for {n_accounts} accounts."
             )),
         });
-        ::tracing::event!(
-            ::tracing::Level::INFO,
-            account_id = 0,
-            "Finished background fetch for {n_accounts} accounts."
-        );
     }
 
     /// Auxiliary function for [Accounts::background_fetch].
@@ -462,11 +448,6 @@ impl Accounts {
                 id: 0,
                 typ: EventType::Warning("Background fetch timed out.".to_string()),
             });
-            ::tracing::event!(
-                ::tracing::Level::WARN,
-                account_id = 0,
-                "Background fetch timed out."
-            );
         }
         events.emit(Event {
             id: 0,
@@ -549,7 +530,7 @@ impl Accounts {
         }
     }
 
-    /// Emits a single event.
+    /// Emits a single event with ID 0, which is not used by any accounts.
     pub fn emit_event(&self, event: EventType) {
         self.events.emit(Event { id: 0, typ: event })
     }

src/accounts.rs

@@ -3,6 +3,7 @@
 #![allow(missing_docs)]
 
 use crate::context::Context;
+use crate::events::EventType;
 
 mod stream;
 
@@ -12,15 +13,9 @@ macro_rules! info {
     ($ctx:expr,  $msg:expr) => {
         info!($ctx, $msg,)
     };
-    ($ctx:expr, $msg:expr, $($args:expr),* $(,)?) => {{
-        let formatted = format!($msg, $($args),*);
-        let full = format!("{file}:{line}: {msg}",
-                           file = file!(),
-                           line = line!(),
-                           msg = &formatted);
-        ::tracing::event!(::tracing::Level::INFO, account_id = $ctx.get_id(), "{}", &formatted);
-        $ctx.emit_event($crate::EventType::Info(full));
-    }};
+    ($ctx:expr, $msg:expr, $($args:expr),* $(,)?) => {
+        $ctx.log_info(file!(), line!(), format!($msg, $($args),*))
+    };
 }
 
 // Workaround for <https://github.com/rust-lang/rust/issues/133708>.
@@ -30,15 +25,9 @@ mod warn_macro_mod {
         ($ctx:expr, $msg:expr) => {
             warn_macro!($ctx, $msg,)
         };
-        ($ctx:expr, $msg:expr, $($args:expr),* $(,)?) => {{
-            let formatted = format!($msg, $($args),*);
-            let full = format!("{file}:{line}: {msg}",
-                               file = file!(),
-                               line = line!(),
-                               msg = &formatted);
-            ::tracing::event!(::tracing::Level::WARN, account_id = $ctx.get_id(), "{}", &formatted);
-            $ctx.emit_event($crate::EventType::Warning(full));
-        }};
+        ($ctx:expr, $msg:expr, $($args:expr),* $(,)?) => {
+            $ctx.log_warn(file!(), line!(), format!($msg, $($args),*))
+        };
     }
 
     pub(crate) use warn_macro;
@@ -50,15 +39,25 @@ macro_rules! error {
     ($ctx:expr, $msg:expr) => {
         error!($ctx, $msg,)
     };
-    ($ctx:expr, $msg:expr, $($args:expr),* $(,)?) => {{
-        let formatted = format!($msg, $($args),*);
-        ::tracing::event!(::tracing::Level::ERROR, account_id = $ctx.get_id(), "{}", &formatted);
-        $ctx.set_last_error(&formatted);
-        $ctx.emit_event($crate::EventType::Error(formatted));
-    }};
+    ($ctx:expr, $msg:expr, $($args:expr),* $(,)?) => {
+        $ctx.log_error(format!($msg, $($args),*))
+    };
 }
 
 impl Context {
+    pub(crate) fn log_info(&self, file: &str, line: u32, msg: String) {
+        self.emit_event(EventType::Info(format!("{file}:{line}: {msg}")));
+    }
+
+    pub(crate) fn log_warn(&self, file: &str, line: u32, msg: String) {
+        self.emit_event(EventType::Warning(format!("{file}:{line}: {msg}")));
+    }
+
+    pub(crate) fn log_error(&self, msg: String) {
+        self.set_last_error(&msg);
+        self.emit_event(EventType::Error(msg));
+    }
+
     /// Set last error string.
     /// Implemented as blocking as used from macros in different, not always async blocks.
     pub fn set_last_error(&self, error: &str) {
@@ -116,12 +115,6 @@ impl<T, E: std::fmt::Display> LogExt<T, E> for Result<T, E> {
             );
             // We can't use the warn!() macro here as the file!() and line!() macros
             // don't work with #[track_caller]
-            tracing::event!(
-                ::tracing::Level::WARN,
-                account_id = context.get_id(),
-                "{}",
-                &full
-            );
             context.emit_event(crate::EventType::Warning(full));
         };
         self

src/log.rs

@@ -93,11 +93,6 @@ impl<S: SessionStream> AsyncRead for LoggingStream<S> {
                 "Read error on stream {peer_addr:?} after reading {} and writing {} bytes: {err}.",
                 this.metrics.total_read, this.metrics.total_written
             );
-            tracing::event!(
-                ::tracing::Level::WARN,
-                account_id = *this.account_id,
-                log_message
-            );
             this.events.emit(Event {
                 id: *this.account_id,
                 typ: EventType::Warning(log_message),