add target method delegation

This patch replaces some code in the record targets with target method
delegation.

record-full.c stores pointers to many target methods when the record
target is pushed.  Then it later delegates some calls via these.  This
is wrong because it violates the target stack contract.  In particular
it is ok to unpush a target at any stratum, but record-full does not
keep track of this, so it could potentially call into an unpushed
target.

This patch fixes the problem by using the newly-introduced generic
approach to target delegation for the methods in question.

2014-02-19  Tom Tromey  <tromey@redhat.com>

	* record-full.c (record_full_beneath_to_resume_ops)
	(record_full_beneath_to_resume, record_full_beneath_to_wait_ops)
	(record_full_beneath_to_wait)
	(record_full_beneath_to_store_registers_ops)
	(record_full_beneath_to_store_registers)
	(record_full_beneath_to_xfer_partial_ops)
	(record_full_beneath_to_xfer_partial)
	(record_full_beneath_to_insert_breakpoint_ops)
	(record_full_beneath_to_insert_breakpoint)
	(record_full_beneath_to_remove_breakpoint_ops)
	(record_full_beneath_to_remove_breakpoint)
	(record_full_beneath_to_stopped_by_watchpoint)
	(record_full_beneath_to_stopped_data_address)
	(record_full_beneath_to_async, tmp_to_resume_ops, tmp_to_resume)
	(tmp_to_wait_ops, tmp_to_wait, tmp_to_store_registers_ops)
	(tmp_to_store_registers, tmp_to_xfer_partial_ops)
	(tmp_to_xfer_partial, tmp_to_instmp_to_insert_breakpoint_ops)
	(tmp_to_insert_breakpoint, tmp_to_remove_breakpoint_ops)
	(tmp_to_remove_breakpoint, tmp_to_stopped_by_watchpoint)
	(tmp_to_stopped_data_address, tmp_to_async): Remove.
	(record_full_open_1, record_full_open): Update.  Use RECORD_IS_USED.
	(record_full_resume, record_full_wait_1)
	(record_full_stopped_by_watchpoint, record_full_stopped_data_address)
	(record_full_store_registers, record_full_xfer_partial)
	(record_full_insert_breakpoint, record_full_remove_breakpoint)
	(record_full_async, record_full_core_xfer_partial): Use target
	delegation.
	* target-delegates.c: Rebuild.
	* target.c (current_xfer_partial): Remove.
	(update_current_target): Do not INHERIT or de_fault
	to_insert_breakpoint, to_remove_breakpoint,
	to_stopped_data_address, to_stopped_by_watchpoint, to_can_async_p,
	to_is_async_p, to_async.  Do not set to_xfer_partial field.
	(default_xfer_partial): Simplify.
	(current_xfer_partial): Remove.
	(target_wait, target_resume): Simplify.
	(find_default_can_async_p, find_default_is_async_p): Update.
	(init_dummy_target): Don't set to_can_async_p, to_is_async_p,
	to_xfer_partial, to_stopped_by_watchpoint,
	to_stopped_data_address.
	(target_store_registers): Simplify.
	(forward_target_remove_breakpoint)
	(forward_target_insert_breakpoint): Remove.
	(target_remove_breakpoint, target_insert_breakpoint)
	(debug_to_insert_breakpoint, debug_to_remove_breakpoint): Update.
	* target.h (struct target_ops) <to_resume, to_wait,
	to_store_registers, to_insert_breakpoint, to_remove_breakpoint,
	to_stopped_by_watchpoint, to_stopped_data_address, to_can_async_p,
	to_is_async_p, to_async, to_xfer_partial>: Add TARGET_DEFAULT
	markup.
	(forward_target_remove_breakpoint)
	(forward_target_insert_breakpoint): Remove.
	* record-btrace.c (record_btrace_remove_breakpoint): Delegate
	directly.
	(record_btrace_insert_breakpoint): Delegate directly.

1 files changed, 152 insertions, 0 deletions

diff --git a/gdb/target-delegates.c b/gdb/target-delegates.c
index cf6364dcf46..2d6ce79be16 100644
--- a/gdb/target-delegates.c
+++ b/gdb/target-delegates.c
@@ -4,11 +4,163 @@
 /* To regenerate this file, run:*/
 /*      make-target-delegates target.h > target-delegates.c */
 static void
+delegate_resume (struct target_ops *self, ptid_t arg1, int arg2, enum gdb_signal arg3)
+{
+  self = self->beneath;
+  self->to_resume (self, arg1, arg2, arg3);
+}
+
+static void
+tdefault_resume (struct target_ops *self, ptid_t arg1, int arg2, enum gdb_signal arg3)
+{
+  noprocess ();
+}
+
+static ptid_t
+delegate_wait (struct target_ops *self, ptid_t arg1, struct target_waitstatus *arg2, int arg3)
+{
+  self = self->beneath;
+  return self->to_wait (self, arg1, arg2, arg3);
+}
+
+static ptid_t
+tdefault_wait (struct target_ops *self, ptid_t arg1, struct target_waitstatus *arg2, int arg3)
+{
+  noprocess ();
+}
+
+static void
+delegate_store_registers (struct target_ops *self, struct regcache *arg1, int arg2)
+{
+  self = self->beneath;
+  self->to_store_registers (self, arg1, arg2);
+}
+
+static void
+tdefault_store_registers (struct target_ops *self, struct regcache *arg1, int arg2)
+{
+  noprocess ();
+}
+
+static int
+delegate_insert_breakpoint (struct target_ops *self, struct gdbarch *arg1, struct bp_target_info *arg2)
+{
+  self = self->beneath;
+  return self->to_insert_breakpoint (self, arg1, arg2);
+}
+
+static int
+delegate_remove_breakpoint (struct target_ops *self, struct gdbarch *arg1, struct bp_target_info *arg2)
+{
+  self = self->beneath;
+  return self->to_remove_breakpoint (self, arg1, arg2);
+}
+
+static int
+delegate_stopped_by_watchpoint (struct target_ops *self)
+{
+  self = self->beneath;
+  return self->to_stopped_by_watchpoint (self);
+}
+
+static int
+tdefault_stopped_by_watchpoint (struct target_ops *self)
+{
+  return 0;
+}
+
+static int
+delegate_stopped_data_address (struct target_ops *self, CORE_ADDR *arg1)
+{
+  self = self->beneath;
+  return self->to_stopped_data_address (self, arg1);
+}
+
+static int
+tdefault_stopped_data_address (struct target_ops *self, CORE_ADDR *arg1)
+{
+  return 0;
+}
+
+static int
+delegate_can_async_p (struct target_ops *self)
+{
+  self = self->beneath;
+  return self->to_can_async_p (self);
+}
+
+static int
+delegate_is_async_p (struct target_ops *self)
+{
+  self = self->beneath;
+  return self->to_is_async_p (self);
+}
+
+static void
+delegate_async (struct target_ops *self, async_callback_ftype *arg1, void *arg2)
+{
+  self = self->beneath;
+  self->to_async (self, arg1, arg2);
+}
+
+static void
+tdefault_async (struct target_ops *self, async_callback_ftype *arg1, void *arg2)
+{
+  tcomplain ();
+}
+
+static enum target_xfer_status 
+delegate_xfer_partial (struct target_ops *self, enum target_object  arg1, const char *arg2, gdb_byte *arg3, const gdb_byte *arg4, ULONGEST arg5, ULONGEST arg6, ULONGEST *arg7)
+{
+  self = self->beneath;
+  return self->to_xfer_partial (self, arg1, arg2, arg3, arg4, arg5, arg6, arg7);
+}
+
+static enum target_xfer_status 
+tdefault_xfer_partial (struct target_ops *self, enum target_object  arg1, const char *arg2, gdb_byte *arg3, const gdb_byte *arg4, ULONGEST arg5, ULONGEST arg6, ULONGEST *arg7)
+{
+  return TARGET_XFER_E_IO;
+}
+
+static void
 install_delegators (struct target_ops *ops)
 {
+  if (ops->to_resume == NULL)
+    ops->to_resume = delegate_resume;
+  if (ops->to_wait == NULL)
+    ops->to_wait = delegate_wait;
+  if (ops->to_store_registers == NULL)
+    ops->to_store_registers = delegate_store_registers;
+  if (ops->to_insert_breakpoint == NULL)
+    ops->to_insert_breakpoint = delegate_insert_breakpoint;
+  if (ops->to_remove_breakpoint == NULL)
+    ops->to_remove_breakpoint = delegate_remove_breakpoint;
+  if (ops->to_stopped_by_watchpoint == NULL)
+    ops->to_stopped_by_watchpoint = delegate_stopped_by_watchpoint;
+  if (ops->to_stopped_data_address == NULL)
+    ops->to_stopped_data_address = delegate_stopped_data_address;
+  if (ops->to_can_async_p == NULL)
+    ops->to_can_async_p = delegate_can_async_p;
+  if (ops->to_is_async_p == NULL)
+    ops->to_is_async_p = delegate_is_async_p;
+  if (ops->to_async == NULL)
+    ops->to_async = delegate_async;
+  if (ops->to_xfer_partial == NULL)
+    ops->to_xfer_partial = delegate_xfer_partial;
 }
 
 static void
 install_dummy_methods (struct target_ops *ops)
 {
+  ops->to_resume = tdefault_resume;
+  ops->to_wait = tdefault_wait;
+  ops->to_store_registers = tdefault_store_registers;
+  ops->to_insert_breakpoint = memory_insert_breakpoint;
+  ops->to_remove_breakpoint = memory_remove_breakpoint;
+  ops->to_stopped_by_watchpoint = tdefault_stopped_by_watchpoint;
+  ops->to_stopped_data_address = tdefault_stopped_data_address;
+  ops->to_can_async_p = find_default_can_async_p;
+  ops->to_is_async_p = find_default_is_async_p;
+  ops->to_async = tdefault_async;
+  ops->to_xfer_partial = tdefault_xfer_partial;
 }