Set breakpoint at url, line number

runtime/vm/debugger.cc

Index: runtime/vm/debugger.cc
===================================================================
--- runtime/vm/debugger.cc	(revision 3366)
+++ runtime/vm/debugger.cc	(working copy)
@@ -274,8 +274,13 @@
 }
 
 
-Breakpoint* Debugger::SetBreakpointAtEntry(const Function& target_function) {
-  ASSERT(!target_function.IsNull());
+Breakpoint* Debugger::SetBreakpoint(const Function& target_function,
+                                    intptr_t token_index) {
+  if ((token_index < target_function.token_index()) ||
+      (target_function.end_token_index() <= token_index)) {
+    // The given token position is not within the target function.
+    return NULL;
+  }

[siva, 2012/01/18 01:32:03]

Shouldn't we check in the breakpoint list that you have to see if a breakpoint
already exists at this function/token_index?

Maybe a TODO here if you want to do this in another CL.

[hausner, 2012/01/18 23:26:38]

Done

   if (!target_function.HasCode()) {
     Compiler::CompileFunction(target_function);
   }
@@ -283,6 +288,9 @@
   ASSERT(!code.IsNull());
   PcDescriptors& desc = PcDescriptors::Handle(code.pc_descriptors());
   for (int i = 0; i < desc.Length(); i++) {
+    if (desc.TokenIndex(i) < token_index) {
+      continue;
+    }

[siva, 2012/01/18 01:32:03]

If 'i' happens to be the last descriptor in this function does it make sense to
set a breakpoint at this index as we won't find anymore descriptors and will end
up not setting a breakpoint.

[hausner, 2012/01/18 23:26:38]

We return NULL if there is no possible PC location for a breakpoint after the
requested breakpoint location. If the requested breakpoint location is
(textually) outside the function, we don't even get here in the first place.

     PcDescriptors::Kind kind = desc.DescriptorKind(i);
     Breakpoint* bpt = NULL;
     if (kind == PcDescriptors::kIcCall) {
@@ -292,25 +300,61 @@
     } else if (kind == PcDescriptors::kOther) {
       if ((desc.TokenIndex(i) > 0) && CodePatcher::IsDartCall(desc.PC(i))) {
         CodePatcher::PatchStaticCallAt(
-            desc.PC(i), StubCode::BreakpointStaticEntryPoint());
+          desc.PC(i), StubCode::BreakpointStaticEntryPoint());
         bpt = new Breakpoint(target_function, i);
       }
     }
     if (bpt != NULL) {
       if (verbose) {
         OS::Print("Setting breakpoint at '%s' line %d  (PC %p)\n",
-            String::Handle(bpt->SourceUrl()).ToCString(),
-            bpt->LineNumber(),
-            bpt->pc());
+                  String::Handle(bpt->SourceUrl()).ToCString(),
+                  bpt->LineNumber(),
+                  bpt->pc());
       }
       AddBreakpoint(bpt);
       return bpt;
     }
   }

[siva, 2012/01/18 01:32:03]

why did you drop "return NULL"; ?

[hausner, 2012/01/18 23:26:38]

Accident. I need automated test cases sooner than later. Thanks!

-  return NULL;
 }
 
 
+Breakpoint* Debugger::SetBreakpointAtEntry(const Function& target_function) {
+  ASSERT(!target_function.IsNull());
+  return SetBreakpoint(target_function, target_function.token_index());
+}
+
+
+Breakpoint* Debugger::SetBreakpointAtLine(const String& script_url,
+                                          intptr_t line_number) {
+  Library& lib = Library::Handle();
+  Script& script = Script::Handle();
+  Isolate* isolate = Isolate::Current();
+  ASSERT(isolate != NULL);
+  lib = isolate->object_store()->registered_libraries();
+  while (!lib.IsNull()) {
+    script = lib.LookupScript(script_url);
+    if (!script.IsNull()) {
+      break;
+    }
+    lib = lib.next_registered();
+  }
+  if (script.IsNull()) {
+    return NULL;
+  }
+  intptr_t token_index_at_line = script.TokenIndexAtLine(line_number);
+  if (token_index_at_line < 0) {
+    // Script does not contain the given line number.
+    return NULL;
+  }
+  const Function& func =
+      Function::Handle(lib.LookupFunctionInScript(script, token_index_at_line));
+  if (func.IsNull()) {
+    return NULL;
+  }
+  return SetBreakpoint(func, token_index_at_line);
+}
+
+
 void Debugger::VisitObjectPointers(ObjectPointerVisitor* visitor) {
   ASSERT(visitor != NULL);
   Breakpoint* bpt = this->breakpoints_;