runtime: fix gdb support for channels.
R=rsc
CC=golang-dev
https://golang.org/cl/4418043
diff --git a/src/pkg/runtime/chan.c b/src/pkg/runtime/chan.c
index 2fab9e2..f2bdad2 100644
--- a/src/pkg/runtime/chan.c
+++ b/src/pkg/runtime/chan.c
@@ -9,7 +9,6 @@
static int32 debug = 0;
-typedef struct Link Link;
typedef struct WaitQ WaitQ;
typedef struct SudoG SudoG;
typedef struct Select Select;
@@ -51,12 +50,6 @@
// chanbuf(c, i) is pointer to the i'th slot in the buffer.
#define chanbuf(c, i) ((byte*)((c)+1)+(uintptr)(c)->elemsize*(i))
-struct Link
-{
- Link* link; // asynch queue circular linked list
- byte elem[8]; // asynch queue data element (+ more)
-};
-
enum
{
// Scase.kind
diff --git a/src/pkg/runtime/runtime-gdb.py b/src/pkg/runtime/runtime-gdb.py
index 08772a4..3f767fb 100644
--- a/src/pkg/runtime/runtime-gdb.py
+++ b/src/pkg/runtime/runtime-gdb.py
@@ -122,10 +122,13 @@
return str(self.val.type)
def children(self):
- ptr = self.val['recvdataq']
- for idx in range(self.val["qcount"]):
- yield ('[%d]' % idx, ptr['elem'])
- ptr = ptr['link']
+ # see chan.c chanbuf()
+ et = [x.type for x in self.val['free'].type.target().fields() if x.name == 'elem'][0]
+ ptr = (self.val.address + 1).cast(et.pointer())
+ for i in range(self.val["qcount"]):
+ j = (self.val["recvx"] + i) % self.val["dataqsiz"]
+ yield ('[%d]' % i, (ptr + j).dereference())
+
#
# Register all the *Printer classes above.
