Fix a new warning on Cygwin

[binutils-gdb.git] / gdb / process-stratum-target.c

diff --git a/gdb/process-stratum-target.c b/gdb/process-stratum-target.c
index 2cb6dfc251ae1520acba7fc314ae3e9cb5bb894a..50bb13e4b83394bd88f9a5f603ea55bcc8f6b9ed 100644 (file)
--- a/gdb/process-stratum-target.c
+++ b/gdb/process-stratum-target.c
@@ -1,6 +1,6 @@
 /* Abstract base class inherited by all process_stratum targets
 
-   Copyright (C) 2018-2021 Free Software Foundation, Inc.
+   Copyright (C) 2018-2022 Free Software Foundation, Inc.
 
    This file is part of GDB.
 
@@ -20,6 +20,7 @@
 #include "defs.h"
 #include "process-stratum-target.h"
 #include "inferior.h"
+#include <algorithm>
 
 process_stratum_target::~process_stratum_target ()
 {
@@ -84,6 +85,8 @@ process_stratum_target::has_execution (inferior *inf)
   return inf->pid != 0;
 }
 
+/* See process-stratum-target.h.  */
+
 void
 process_stratum_target::follow_exec (inferior *follow_inf, ptid_t ptid,
                                     const char *execd_pathname)
@@ -106,6 +109,21 @@ process_stratum_target::follow_exec (inferior *follow_inf, ptid_t ptid,
 
 /* See process-stratum-target.h.  */
 
+void
+process_stratum_target::follow_fork (inferior *child_inf, ptid_t child_ptid,
+                                    target_waitkind fork_kind,
+                                    bool follow_child,
+                                    bool detach_on_fork)
+{
+  if (child_inf != nullptr)
+    {
+      child_inf->push_target (this);
+      add_thread_silent (this, child_ptid);
+    }
+}
+
+/* See process-stratum-target.h.  */
+
 void
 process_stratum_target::maybe_add_resumed_with_pending_wait_status
   (thread_info *thread)
@@ -140,6 +158,48 @@ process_stratum_target::maybe_remove_resumed_with_pending_wait_status
 
 /* See process-stratum-target.h.  */
 
+thread_info *
+process_stratum_target::random_resumed_with_pending_wait_status
+  (inferior *inf, ptid_t filter_ptid)
+{
+  auto matches = [inf, filter_ptid] (const thread_info &thread)
+    {
+      return thread.inf == inf && thread.ptid.matches (filter_ptid);
+    };
+
+  /* First see how many matching events we have.  */
+  const auto &l = m_resumed_with_pending_wait_status;
+  unsigned int count = std::count_if (l.begin (), l.end (), matches);
+
+  if (count == 0)
+    return nullptr;
+
+  /* Now randomly pick a thread out of those that match the criteria.  */
+  int random_selector
+    = (int) ((count * (double) rand ()) / (RAND_MAX + 1.0));
+
+  if (count > 1)
+    infrun_debug_printf ("Found %u events, selecting #%d",
+                        count, random_selector);
+
+  /* Select the Nth thread that matches.  */
+  auto it = std::find_if (l.begin (), l.end (),
+                         [&random_selector, &matches]
+                         (const thread_info &thread)
+    {
+      if (!matches (thread))
+       return false;
+
+      return random_selector-- == 0;
+    });
+
+  gdb_assert (it != l.end ());
+
+  return &*it;
+}
+
+/* See process-stratum-target.h.  */
+
 std::set<process_stratum_target *>
 all_non_exited_process_targets ()
 {