[binutils-gdb] gdbserver: Reset current_thread when the thread is removed.

[Aleksandar Ristovski <aristovski at sourceware dot org>]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=96e7a1eb6d09fda9e22e112e35e7d0085a8f4fd0

commit 96e7a1eb6d09fda9e22e112e35e7d0085a8f4fd0
Author: Aleksandar Ristovski <aristovski@qnx.com>
Date:   Fri Oct 16 11:08:38 2015 -0400

    gdbserver: Reset current_thread when the thread is removed.
    
    Reset current_thread and make sure 'remove_process' is used
    after all associated threads have been removed first.
    
    gdb/gdbserver/ChangeLog:
    	* inferiors.c (thread_pid_matches_callback): New function.
    	(find_thread_process): New function.
    	(remove_thread): Reset current_thread.
    	(remove_process): Assert threads have been removed first.

Diff:
---
 gdb/gdbserver/inferiors.c | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/gdb/gdbserver/inferiors.c b/gdb/gdbserver/inferiors.c
index 21f45fa..72a3ef1 100644
--- a/gdb/gdbserver/inferiors.c
+++ b/gdb/gdbserver/inferiors.c
@@ -141,6 +141,27 @@ find_thread_ptid (ptid_t ptid)
   return (struct thread_info *) find_inferior_id (&all_threads, ptid);
 }
 
+/* Predicate function for matching thread entry's pid to the given
+   pid value passed by address in ARGS.  */
+
+static int
+thread_pid_matches_callback (struct inferior_list_entry *entry, void *args)
+{
+  return (ptid_get_pid (entry->id) == *(pid_t *)args);
+}
+
+/* Find a thread associated with the given PROCESS, or NULL if no
+   such thread exists.  */
+
+static struct thread_info *
+find_thread_process (const struct process_info *const process)
+{
+  pid_t pid = ptid_get_pid (ptid_of (process));
+
+  return (struct thread_info *)
+    find_inferior (&all_threads, thread_pid_matches_callback, &pid);
+}
+
 ptid_t
 gdb_id_to_thread_id (ptid_t gdb_id)
 {
@@ -166,6 +187,8 @@ remove_thread (struct thread_info *thread)
   discard_queued_stop_replies (ptid_of (thread));
   remove_inferior (&all_threads, (struct inferior_list_entry *) thread);
   free_one_thread (&thread->entry);
+  if (current_thread == thread)
+    current_thread = NULL;
 }
 
 /* Return a pointer to the first inferior in LIST, or NULL if there isn't one.
@@ -291,6 +314,7 @@ remove_process (struct process_info *process)
 {
   clear_symbol_cache (&process->symbol_cache);
   free_all_breakpoints (process);
+  gdb_assert (find_thread_process (process) == NULL);
   remove_inferior (&all_processes, &process->entry);
   free (process);
 }