debug: deal with more types, change "visited" check.
Adds typedef, function, and void types. Changes the "visited" check to use
(type, address) as the key, and always applies it. These changes make the
printing of structs, channels, and interfaces slightly better too.
Change-Id: I4f2417f3bc12d277b12c6c7c2876d595b37166fb
Reviewed-on: https://go-review.googlesource.com/1873
Reviewed-by: Rob Pike <r@golang.org>
diff --git a/ogle/program/server/print.go b/ogle/program/server/print.go
index c407cdf..ccf8df3 100644
--- a/ogle/program/server/print.go
+++ b/ogle/program/server/print.go
@@ -16,6 +16,12 @@
// address is a type denoting addresses in the tracee.
type address uintptr
+// typeAndAddress associates an address in the target with a DWARF type.
+type typeAndAddress struct {
+ Type dwarf.Type
+ Address address
+}
+
// Routines to print a value using DWARF type descriptions.
// TODO: Does this deserve its own package? It has no dependencies on Server.
@@ -27,9 +33,9 @@
peeker Peeker
dwarf *dwarf.Data
arch *arch.Architecture
- printBuf bytes.Buffer // Accumulates the output.
- tmp []byte // Temporary used for I/O.
- visited map[address]bool // Prevents looping on cyclic data.
+ printBuf bytes.Buffer // Accumulates the output.
+ tmp []byte // Temporary used for I/O.
+ visited map[typeAndAddress]bool // Prevents looping on cyclic data.
// The cache stores a local copy of part of the address space.
// Saves I/O overhead when scanning map buckets by letting
// printValueAt use the contents of already-read bucket data.
@@ -107,7 +113,7 @@
peeker: peeker,
arch: arch,
dwarf: dwarf,
- visited: make(map[address]bool),
+ visited: make(map[typeAndAddress]bool),
tmp: make([]byte, 100), // Enough for a largish string.
}
}
@@ -198,10 +204,14 @@
// printValueAt pretty-prints the data at the specified addresss
// using the provided type information.
func (p *Printer) printValueAt(typ dwarf.Type, a address) {
- // Make sure we don't recur forever.
- if p.visited[a] {
- p.printf("(@%x...)", a)
- return
+ if a != 0 {
+ // Check if we are repeating the same type and address.
+ ta := typeAndAddress{typ, a}
+ if p.visited[ta] {
+ p.printf("(%v %#x)", typ, a)
+ return
+ }
+ p.visited[ta] = true
}
switch typ := typ.(type) {
case *dwarf.BoolType:
@@ -255,7 +265,6 @@
p.errorf("unrecognized complex size %d", typ.ByteSize)
}
case *dwarf.StructType:
- p.visited[a] = true
if typ.Kind != "struct" {
// Could be "class" or "union".
p.errorf("can't handle struct type %s", typ.Kind)
@@ -272,17 +281,19 @@
case *dwarf.ArrayType:
p.printArrayAt(typ, a)
case *dwarf.MapType:
- p.visited[a] = true
p.printMapAt(typ, a)
case *dwarf.SliceType:
- p.visited[a] = true
p.printSliceAt(typ, a)
case *dwarf.StringType:
p.printStringAt(typ, a)
case *dwarf.TypedefType:
- p.errorf("unimplemented typedef type %T %v", typ, typ)
+ p.printValueAt(typ.Type, a)
+ case *dwarf.FuncType:
+ p.printf("%v @%#x ", typ, a)
+ case *dwarf.VoidType:
+ p.printf("void")
default:
- // TODO: chan func interface
+ // TODO: chan interface
p.errorf("unimplemented type %v", typ)
}
}
