Support watchpoints

src/gdbserver.rs

@@ -13,7 +13,9 @@ use tokio::{
     sync::{mpsc, oneshot},
 };
 
-use crate::emulator::{DebugEvent, DebugStopReason, EmulatorClient, EmulatorCommand, SimId};
+use crate::emulator::{
+    DebugEvent, DebugStopReason, EmulatorClient, EmulatorCommand, SimId, VBWatchpointType,
+};
 
 mod registers;
 mod request;
@@ -187,7 +189,7 @@ impl GdbConnection {
                 }
                 self.stop_reason = Some(reason);
                 self.response()
-                    .write_str(debug_stop_reason_string(self.stop_reason))
+                    .write_str(&debug_stop_reason_string(self.stop_reason))
             }
         };
         Some(res)
@@ -251,7 +253,7 @@ impl GdbConnection {
             bail!("debug process was killed");
         } else if req.match_str("?") {
             self.response()
-                .write_str(debug_stop_reason_string(self.stop_reason))
+                .write_str(&debug_stop_reason_string(self.stop_reason))
         } else if req.match_some_str(["c", "vCont;c:"]).is_some() {
             self.client
                 .send_command(EmulatorCommand::DebugContinue(self.sim_id));
@@ -329,18 +331,68 @@ impl GdbConnection {
             } else {
                 self.response()
             }
-        } else if req.match_str("Z0,") {
-            if let Some(address) = req.match_hex() {
-                self.client
-                    .send_command(EmulatorCommand::AddBreakpoint(self.sim_id, address));
+        } else if req.match_str("Z") {
+            let mut parse_request = || {
+                let type_ = req.match_hex::<u8>()?;
+                if !req.match_str(",") {
+                    return None;
+                }
+                let address = req.match_hex()?;
+                if type_ == 0 || type_ == 1 {
+                    return Some(EmulatorCommand::AddBreakpoint(self.sim_id, address));
+                }
+                if !req.match_str(",") {
+                    return None;
+                }
+                let length = req.match_hex()?;
+                let watch = match type_ {
+                    2 => VBWatchpointType::Write,
+                    3 => VBWatchpointType::Read,
+                    4 => VBWatchpointType::Access,
+                    _ => return None,
+                };
+                Some(EmulatorCommand::AddWatchpoint(
+                    self.sim_id,
+                    address,
+                    length,
+                    watch,
+                ))
+            };
+            if let Some(command) = parse_request() {
+                self.client.send_command(command);
                 self.response().write_str("OK")
             } else {
                 self.response()
             }
-        } else if req.match_str("z0,") {
-            if let Some(address) = req.match_hex() {
-                self.client
-                    .send_command(EmulatorCommand::RemoveBreakpoint(self.sim_id, address));
+        } else if req.match_str("z") {
+            let mut parse_request = || {
+                let type_ = req.match_hex::<u8>()?;
+                if !req.match_str(",") {
+                    return None;
+                }
+                let address = req.match_hex()?;
+                if type_ == 0 || type_ == 1 {
+                    return Some(EmulatorCommand::RemoveBreakpoint(self.sim_id, address));
+                }
+                if !req.match_str(",") {
+                    return None;
+                }
+                let length = req.match_hex()?;
+                let watch = match type_ {
+                    2 => VBWatchpointType::Write,
+                    3 => VBWatchpointType::Read,
+                    4 => VBWatchpointType::Access,
+                    _ => return None,
+                };
+                Some(EmulatorCommand::RemoveWatchpoint(
+                    self.sim_id,
+                    address,
+                    length,
+                    watch,
+                ))
+            };
+            if let Some(command) = parse_request() {
+                self.client.send_command(command);
                 self.response().write_str("OK")
             } else {
                 self.response()
@@ -367,11 +419,38 @@ impl Drop for GdbConnection {
     }
 }
 
-fn debug_stop_reason_string(reason: Option<DebugStopReason>) -> &'static str {
-    match reason {
-        Some(DebugStopReason::Trace) => "T05;thread:p1.t1;threads:p1.t1;reason:trace;",
-        Some(DebugStopReason::Breakpoint) => "T05;thread:p1.t1;threads:p1.t1;reason:breakpoint;",
-        Some(DebugStopReason::Trapped) => "T05;swbreak;thread:p1.t1;threads:p1.t1;reason:trap;",
-        None => "T00;thread:p1.t1;threads:p1.t1;",
+fn debug_stop_reason_string(reason: Option<DebugStopReason>) -> String {
+    let mut result = String::new();
+    result += if reason.is_some() { "T05;" } else { "T00;" };
+    if let Some(DebugStopReason::Breakpoint) = reason {
+        result += "swbreak;";
     }
+    if let Some(DebugStopReason::Watchpoint(watch, address)) = reason {
+        result += match watch {
+            VBWatchpointType::Write => "watch:",
+            VBWatchpointType::Read => "rwatch:",
+            VBWatchpointType::Access => "awatch:",
+        };
+        result += &format!("{address:08x};");
+    }
+
+    result += "thread:p1.t1;threads:p1.t1;";
+
+    if let Some(reason) = reason {
+        result += "reason:";
+        result += match reason {
+            DebugStopReason::Trace => "trace;",
+            DebugStopReason::Breakpoint => "breakpoint;",
+            DebugStopReason::Watchpoint(_, _) => "watchpoint;",
+            DebugStopReason::Trapped => "trap;",
+        };
+    }
+
+    if let Some(DebugStopReason::Watchpoint(_, address)) = reason {
+        result += "description:";
+        result += &hex::encode(address.to_string());
+        result += ";";
+    }
+
+    result
 }