Add target method for converting thread handle to thread_info struct pointer

This patch adds a target method named `to_thread_handle_to_thread_info'.
It is intended to map a thread library specific thread handle (such as
pthread_t for the pthread library) to the corresponding GDB internal
thread_info struct (pointer).

An implementation is provided for Linux pthreads; see linux-thread-db.c.

gdb/ChangeLog:

	* target.h (struct target_ops): Add to_thread_handle_to_thread_info.
	(target_thread_handle_to_thread_info): Declare.
	* target.c (target_thread_handle_to_thread_info): New function.
	* target-delegates.c: Regenerate.
	* gdbthread.h (find_thread_by_handle): Declare.
	* thread.c (find_thread_by_handle): New function.
	* linux-thread-db.c (thread_db_thread_handle_to_thread_info): New
	function.
	(init_thread_db_ops): Register thread_db_thread_handle_to_thread_info.

1 files changed, 4 insertions, 0 deletions

diff --git a/gdb/gdbthread.h b/gdb/gdbthread.h
index fe7acc2..d5101ab 100644
--- a/gdb/gdbthread.h
+++ b/gdb/gdbthread.h
@@ -448,6 +448,10 @@ extern struct thread_info *find_thread_ptid (ptid_t ptid);
 /* Find thread by GDB global thread ID.  */
 struct thread_info *find_thread_global_id (int global_id);
 
+/* Find thread by thread library specific handle in inferior INF.  */
+struct thread_info *find_thread_by_handle (struct value *thread_handle,
+					   struct inferior *inf);
+
 /* Finds the first thread of the inferior given by PID.  If PID is -1,
    returns the first thread in the list.  */
 struct thread_info *first_thread_of_process (int pid);