feat: implement software breakpoints

src/State.zig

@@ -1,6 +1,62 @@
 const std = @import("std");
 
+const Allocator = std.mem.Allocator;
+const ArrayList = std.ArrayList;
+
 hw_bkpt: HwBkpt = .{},
+sw_bkpt: SwBkpt,
+
+pub fn init(allocator: Allocator) @This() {
+    return .{ .sw_bkpt = SwBkpt.init(allocator) };
+}
+
+pub fn deinit(self: *@This()) void {
+    self.sw_bkpt.deinit();
+    self.* = undefined;
+}
+
+const SwBkpt = struct {
+    const log = std.log.scoped(.SwBkpt);
+
+    list: std.ArrayList(Bkpt),
+
+    pub fn init(allocator: Allocator) @This() {
+        return .{ .list = ArrayList(Bkpt).init(allocator) };
+    }
+
+    pub fn deinit(self: *@This()) void {
+        self.deinit();
+        self.* = undefined;
+    }
+
+    pub fn isHit(self: *const @This(), addr: u32) bool {
+        for (self.list.items) |bkpt| {
+            if (bkpt.addr == addr) return true;
+        }
+
+        return false;
+    }
+
+    pub fn add(self: *@This(), addr: u32, kind: u32) !void {
+        for (self.list.items) |bkpt| {
+            if (bkpt.addr == addr) return; // indempotent
+        }
+
+        try self.list.append(.{ .addr = addr, .kind = try Bkpt.Kind.from(u32, kind) });
+        log.warn("Added Breakpoint at 0x{X:0>8}", .{addr});
+    }
+
+    pub fn remove(self: *@This(), addr: u32) void {
+        for (self.list.items) |bkpt, i| {
+            if (bkpt.addr == addr) {
+                _ = self.list.orderedRemove(i);
+                log.debug("Removed Breakpoint at 0x{X:0>8}", .{addr});
+
+                return;
+            }
+        }
+    }
+};
 
 const HwBkpt = struct {
     const log = std.log.scoped(.HwBkpt);
@@ -9,9 +65,7 @@ const HwBkpt = struct {
 
     pub fn isHit(self: *const @This(), addr: u32) bool {
         for (self.list) |bkpt_opt| {
-            if (bkpt_opt == null) continue;
-            const bkpt = bkpt_opt.?;
-
+            const bkpt = bkpt_opt orelse continue;
             if (bkpt.addr == addr) return true;
         }
 
@@ -20,17 +74,14 @@ const HwBkpt = struct {
 
     pub fn add(self: *@This(), addr: u32, kind: u32) !void {
         for (self.list) |*bkpt_opt| {
-            if (bkpt_opt.* != null) {
-                const bkpt = bkpt_opt.*.?;
-                if (bkpt.addr == addr) return; // makes this fn indempotent
+            if (bkpt_opt.*) |bkpt| {
+                if (bkpt.addr == addr) return; // idempotent
+            } else {
+                bkpt_opt.* = .{ .addr = addr, .kind = try Bkpt.Kind.from(u32, kind) };
+                log.debug("Added Breakpoint at 0x{X:0>8}", .{addr});
 
-                continue;
+                return;
             }
-
-            bkpt_opt.* = .{ .addr = addr, .kind = try Bkpt.Kind.from(u32, kind) };
-            log.debug("Added Breakpoint at 0x{X:0>8}", .{addr});
-
-            return;
         }
 
         return error.OutOfSpace;
@@ -38,11 +89,14 @@ const HwBkpt = struct {
 
     pub fn remove(self: *@This(), addr: u32) void {
         for (self.list) |*bkpt_opt| {
-            if (bkpt_opt.* == null) continue;
-            const bkpt = bkpt_opt.*.?; // FIXME: bkpt_opt.?.addr works though?
+            const bkpt = bkpt_opt.* orelse continue;
 
-            log.debug("Removed Breakpoint at 0x{X:0>8}", .{addr});
-            if (bkpt.addr == addr) bkpt_opt.* = null;
+            if (bkpt.addr == addr) {
+                bkpt_opt.* = null;
+                log.debug("Removed Breakpoint at 0x{X:0>8}", .{addr});
+
+                break;
+            }
         }
     }
 };