Introduce target_filesystem_is_local

This commit introduces a new target method target_filesystem_is_local
which can be used to determine whether or not the filesystem accessed
by the target_fileio_* methods is the local filesystem.

gdb/ChangeLog:

	* target.h (struct target_ops) <to_filesystem_is_local>:
	New field.
	(target_filesystem_is_local): New macro.
	* target-delegates.c: Regenerate.
	* remote.c (remote_filesystem_is_local): New function.
	(init_remote_ops): Initialize to_filesystem_is_local.

gdb/ChangeLog

@@ -1,3 +1,12 @@
+2015-04-02  Gary Benson <gbenson@redhat.com>
+
+	* target.h (struct target_ops) <to_filesystem_is_local>:
+	New field.
+	(target_filesystem_is_local): New macro.
+	* target-delegates.c: Regenerate.
+	* remote.c (remote_filesystem_is_local): New function.
+	(init_remote_ops): Initialize to_filesystem_is_local.
+
 2015-04-02  Gary Benson <gbenson@redhat.com>
 
 	* target.h (struct target_ops) <to_fileio_fstat>: New field.

gdb/remote.c

@@ -9863,6 +9863,15 @@ remote_hostio_send_command (int command_bytes, int which_packet,
   return ret;
 }
 
+/* Return nonzero if the filesystem accessed by the target_fileio_*
+   methods is the local filesystem, zero otherwise.  */
+
+static int
+remote_filesystem_is_local (struct target_ops *self)
+{
+  return 0;
+}
+
 /* Open FILENAME on the remote target, using FLAGS and MODE.  Return a
    remote file descriptor, or -1 if an error occurs (and set
    *REMOTE_ERRNO).  */
@@ -11814,6 +11823,7 @@ Specify the serial device it is connected to\n\
   remote_ops.to_supports_multi_process = remote_supports_multi_process;
   remote_ops.to_supports_disable_randomization
     = remote_supports_disable_randomization;
+  remote_ops.to_filesystem_is_local = remote_filesystem_is_local;
   remote_ops.to_fileio_open = remote_hostio_open;
   remote_ops.to_fileio_pwrite = remote_hostio_pwrite;
   remote_ops.to_fileio_pread = remote_hostio_pread;

gdb/target-delegates.c

@@ -2343,6 +2343,33 @@ debug_thread_address_space (struct target_ops *self, ptid_t arg1)
   return result;
 }
 
+static int
+delegate_filesystem_is_local (struct target_ops *self)
+{
+  self = self->beneath;
+  return self->to_filesystem_is_local (self);
+}
+
+static int
+tdefault_filesystem_is_local (struct target_ops *self)
+{
+  return 1;
+}
+
+static int
+debug_filesystem_is_local (struct target_ops *self)
+{
+  int result;
+  fprintf_unfiltered (gdb_stdlog, "-> %s->to_filesystem_is_local (...)\n", debug_target.to_shortname);
+  result = debug_target.to_filesystem_is_local (&debug_target);
+  fprintf_unfiltered (gdb_stdlog, "<- %s->to_filesystem_is_local (", debug_target.to_shortname);
+  target_debug_print_struct_target_ops_p (&debug_target);
+  fputs_unfiltered (") = ", gdb_stdlog);
+  target_debug_print_int (result);
+  fputs_unfiltered ("\n", gdb_stdlog);
+  return result;
+}
+
 static void
 delegate_trace_init (struct target_ops *self)
 {
@@ -4022,6 +4049,8 @@ install_delegators (struct target_ops *ops)
     ops->to_thread_architecture = delegate_thread_architecture;
   if (ops->to_thread_address_space == NULL)
     ops->to_thread_address_space = delegate_thread_address_space;
+  if (ops->to_filesystem_is_local == NULL)
+    ops->to_filesystem_is_local = delegate_filesystem_is_local;
   if (ops->to_trace_init == NULL)
     ops->to_trace_init = delegate_trace_init;
   if (ops->to_download_tracepoint == NULL)
@@ -4225,6 +4254,7 @@ install_dummy_methods (struct target_ops *ops)
   ops->to_can_run_breakpoint_commands = tdefault_can_run_breakpoint_commands;
   ops->to_thread_architecture = default_thread_architecture;
   ops->to_thread_address_space = default_thread_address_space;
+  ops->to_filesystem_is_local = tdefault_filesystem_is_local;
   ops->to_trace_init = tdefault_trace_init;
   ops->to_download_tracepoint = tdefault_download_tracepoint;
   ops->to_can_download_tracepoint = tdefault_can_download_tracepoint;
@@ -4372,6 +4402,7 @@ init_debug_target (struct target_ops *ops)
   ops->to_can_run_breakpoint_commands = debug_can_run_breakpoint_commands;
   ops->to_thread_architecture = debug_thread_architecture;
   ops->to_thread_address_space = debug_thread_address_space;
+  ops->to_filesystem_is_local = debug_filesystem_is_local;
   ops->to_trace_init = debug_trace_init;
   ops->to_download_tracepoint = debug_download_tracepoint;
   ops->to_can_download_tracepoint = debug_can_download_tracepoint;

gdb/target.h

@@ -825,6 +825,12 @@ struct target_ops
 
     /* Target file operations.  */
 
+    /* Return nonzero if the filesystem accessed by the
+       target_fileio_* methods is the local filesystem,
+       zero otherwise.  */
+    int (*to_filesystem_is_local) (struct target_ops *)
+      TARGET_DEFAULT_RETURN (1);
+
     /* Open FILENAME on the target, using FLAGS and MODE.  Return a
        target file descriptor, or -1 if an error occurs (and set
        *TARGET_ERRNO).  */
@@ -1921,6 +1927,11 @@ extern int target_search_memory (CORE_ADDR start_addr,
 
 /* Target file operations.  */
 
+/* Return nonzero if the filesystem accessed by the target_fileio_*
+   methods is the local filesystem, zero otherwise.  */
+#define target_filesystem_is_local() \
+  current_target.to_filesystem_is_local (&current_target)
+
 /* Open FILENAME on the target, using FLAGS and MODE.  Return a
    target file descriptor, or -1 if an error occurs (and set
    *TARGET_ERRNO).  */