Create inferior for tfile target

When a trace file is loaded in Eclipse, it is expected to see thread
and process (=thread-group-started and =thread-created).  Create an
inferior and add a thread for this purpose.

This patch just reverts my previous patch.

gdb/testsuite:

2014-02-05  Yao Qi  <yao@codesourcery.com>

	Revert this patch:

	2013-05-24  Yao Qi  <yao@codesourcery.com>

	* gdb.trace/tfile.exp: Test inferior and thread.

gdb:

2014-02-05  Yao Qi  <yao@codesourcery.com>

	Revert this patch:

	2013-05-24  Yao Qi  <yao@codesourcery.com>

	* tracepoint.c (TFILE_PID): Remove.
	(tfile_open): Don't add thread and inferior.
	(tfile_close): Don't set 'inferior_ptid'.  Don't call
	exit_inferior_silent.
	(tfile_thread_alive): Remove.
	(init_tfile_ops): Don't set field 'to_thread_alive' of
	tfile_ops.

1 files changed, 19 insertions, 0 deletions

diff --git a/gdb/tracepoint.c b/gdb/tracepoint.c
index f3b9bfc..0a50606 100644
--- a/gdb/tracepoint.c
+++ b/gdb/tracepoint.c
@@ -79,6 +79,8 @@
    large.  (400 - 31)/2 == 184 */
 #define MAX_AGENT_EXPR_LEN	184
 
+#define TFILE_PID (1)
+
 /* A hook used to notify the UI of tracepoint operations.  */
 
 void (*deprecated_trace_find_hook) (char *arg, int from_tty);
@@ -4372,6 +4374,10 @@ tfile_open (char *filename, int from_tty)
       throw_exception (ex);
     }
 
+  inferior_appeared (current_inferior (), TFILE_PID);
+  inferior_ptid = pid_to_ptid (TFILE_PID);
+  add_thread_silent (inferior_ptid);
+
   if (ts->traceframe_count <= 0)
     warning (_("No traceframes present in this file."));
 
@@ -4382,6 +4388,8 @@ tfile_open (char *filename, int from_tty)
   merge_uploaded_trace_state_variables (&uploaded_tsvs);
 
   merge_uploaded_tracepoints (&uploaded_tps);
+
+  post_create_inferior (&tfile_ops, from_tty);
 }
 
 /* Interpret the given line from the definitions part of the trace
@@ -4754,6 +4762,10 @@ tfile_close (void)
   if (trace_fd < 0)
     return;
 
+  pid = ptid_get_pid (inferior_ptid);
+  inferior_ptid = null_ptid;	/* Avoid confusion from thread stuff.  */
+  exit_inferior_silent (pid);
+
   close (trace_fd);
   trace_fd = -1;
   xfree (trace_filename);
@@ -5250,6 +5262,12 @@ tfile_has_registers (struct target_ops *ops)
   return traceframe_number != -1;
 }
 
+static int
+tfile_thread_alive (struct target_ops *ops, ptid_t ptid)
+{
+  return 1;
+}
+
 /* Callback for traceframe_walk_blocks.  Builds a traceframe_info
    object for the tfile target's current traceframe.  */
 
@@ -5336,6 +5354,7 @@ init_tfile_ops (void)
   tfile_ops.to_has_stack = tfile_has_stack;
   tfile_ops.to_has_registers = tfile_has_registers;
   tfile_ops.to_traceframe_info = tfile_traceframe_info;
+  tfile_ops.to_thread_alive = tfile_thread_alive;
   tfile_ops.to_magic = OPS_MAGIC;
 }