gdb: Implement native dumpcore function for NetBSD

Define supports_dumpcore and dumpcore for NetBSD, that wraps
the ptrace(2) call with the PT_DUMPCORE operation.

gdb/ChangeLog:

       * nbsd-nat.h (nbsd_nat_target::supports_dumpcore)
       (nbsd_nat_target::dumpcore): New declarations.
       * nbsd-nat.c (nbsd_nat_target::supports_dumpcore)
       (nbsd_nat_target::dumpcore): New functions.

2 files changed, 22 insertions, 0 deletions

diff --git a/gdb/nbsd-nat.c b/gdb/nbsd-nat.c
index 5b59f21..52c4d18 100644
--- a/gdb/nbsd-nat.c
+++ b/gdb/nbsd-nat.c
@@ -890,3 +890,23 @@ nbsd_nat_target::xfer_partial (enum target_object object,
 					      len, xfered_len);
     }
 }
+
+/* Implement the "supports_dumpcore" target_ops method.  */
+
+bool
+nbsd_nat_target::supports_dumpcore ()
+{
+  return true;
+}
+
+/* Implement the "dumpcore" target_ops method.  */
+
+void
+nbsd_nat_target::dumpcore (const char *filename)
+{
+  pid_t pid = inferior_ptid.pid ();
+
+  if (ptrace (PT_DUMPCORE, pid, const_cast<char *>(filename),
+	      strlen (filename)) == -1)
+    perror_with_name (("ptrace"));
+}
diff --git a/gdb/nbsd-nat.h b/gdb/nbsd-nat.h
index 665a71a..b09d5b1 100644
--- a/gdb/nbsd-nat.h
+++ b/gdb/nbsd-nat.h
@@ -55,6 +55,8 @@ struct nbsd_nat_target : public inf_ptrace_target
 					const gdb_byte *writebuf,
 					ULONGEST offset, ULONGEST len,
 					ULONGEST *xfered_len) override;
+  bool supports_dumpcore () override;
+  void dumpcore (const char *filename) override;
 };
 
 #endif /* nbsd-nat.h */