Add DRD as an experimental tool.  Bart Van Assche is the maintainer.


git-svn-id: svn://svn.valgrind.org/valgrind/trunk@7211 a5019735-40e9-0310-863c-91ae7b9d1cf9
diff --git a/exp-drd/drd_cond.c b/exp-drd/drd_cond.c
new file mode 100644
index 0000000..0323fa0
--- /dev/null
+++ b/exp-drd/drd_cond.c
@@ -0,0 +1,201 @@
+/*
+  This file is part of drd, a data race detector.
+
+  Copyright (C) 2006-2007 Bart Van Assche
+  bart.vanassche@gmail.com
+
+  This program is free software; you can redistribute it and/or
+  modify it under the terms of the GNU General Public License as
+  published by the Free Software Foundation; either version 2 of the
+  License, or (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+  General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+  02111-1307, USA.
+
+  The GNU General Public License is contained in the file COPYING.
+*/
+
+
+#include "drd_cond.h"
+#include "drd_error.h"
+#include "drd_mutex.h"
+#include "drd_suppression.h"
+#include "pthread_object_size.h"
+#include "pub_tool_errormgr.h"    // VG_(maybe_record_error)()
+#include "pub_tool_libcassert.h"  // tl_assert()
+#include "pub_tool_libcprint.h"   // VG_(printf)()
+#include "pub_tool_machine.h"     // VG_(get_IP)()
+#include "pub_tool_threadstate.h" // VG_(get_running_tid)()
+#include "pub_core_options.h"     // VG_(clo_backtrace_size)
+
+
+static struct cond_info s_cond[256];
+static Bool s_trace_cond;
+
+
+void cond_set_trace(const Bool trace_cond)
+{
+  s_trace_cond = trace_cond;
+}
+
+static
+void cond_initialize(struct cond_info* const p, const Addr cond)
+{
+  tl_assert(cond != 0);
+
+  p->cond         = cond;
+  p->waiter_count = 0;
+  p->mutex        = 0;
+}
+
+static struct cond_info* cond_get_or_allocate(const Addr cond)
+{
+  int i;
+  for (i = 0; i < sizeof(s_cond)/sizeof(s_cond[0]); i++)
+    if (s_cond[i].cond == cond)
+      return &s_cond[i];
+  for (i = 0; i < sizeof(s_cond)/sizeof(s_cond[0]); i++)
+  {
+    if (s_cond[i].cond == 0)
+    {
+      cond_initialize(&s_cond[i], cond);
+      /* TO DO: replace the constant below by a symbolic constant referring */
+      /* to sizeof(pthread_cond_t).                                        */
+      drd_start_suppression(cond, cond + PTHREAD_COND_SIZE, "cond");
+      return &s_cond[i];
+    }
+  }
+  tl_assert(0);
+  return 0;
+}
+
+void cond_init(const Addr cond)
+{
+  if (s_trace_cond)
+  {
+    VG_(message)(Vg_UserMsg, "Initializing condition variable 0x%lx", cond);
+    VG_(get_and_pp_StackTrace)(VG_(get_running_tid)(),
+                               VG_(clo_backtrace_size));
+  }
+  tl_assert(cond_get(cond) == 0);
+  cond_get_or_allocate(cond);
+}
+
+void cond_destroy(struct cond_info* const p)
+{
+  if (s_trace_cond)
+  {
+    VG_(message)(Vg_UserMsg, "Destroying condition variable 0x%lx", p->cond);
+    VG_(get_and_pp_StackTrace)(VG_(get_running_tid)(),
+                               VG_(clo_backtrace_size));
+  }
+
+  // TO DO: print a proper error message if waiter_count != 0.
+  tl_assert(p->waiter_count == 0);
+
+  drd_finish_suppression(p->cond, p->cond + PTHREAD_COND_SIZE);
+
+  p->cond         = 0;
+  p->waiter_count = 0;
+  p->mutex        = 0;
+}
+
+struct cond_info* cond_get(const Addr cond)
+{
+  int i;
+  for (i = 0; i < sizeof(s_cond)/sizeof(s_cond[0]); i++)
+    if (s_cond[i].cond == cond)
+      return &s_cond[i];
+  return 0;
+}
+
+int cond_pre_wait(const Addr cond, const Addr mutex)
+{
+  struct cond_info* p;
+
+  p = cond_get_or_allocate(cond);
+  if (p->waiter_count == 0)
+  {
+    p->mutex = mutex;
+  }
+  else
+  {
+    // TO DO: print a proper error message if two different threads call
+    // pthread_cond_*wait() on the same condition variable but with a different
+    // mutex argument.
+    tl_assert(p->mutex == mutex);
+  }
+  return ++p->waiter_count;
+}
+
+int cond_post_wait(const Addr cond)
+{
+  struct cond_info* p;
+
+  p = cond_get(cond);
+  tl_assert(p);
+  tl_assert(p->waiter_count > 0);
+  tl_assert(p->mutex);
+  if (--p->waiter_count == 0)
+  {
+    p->mutex = 0;
+  }
+  return p->waiter_count;
+}
+
+void cond_pre_signal(Addr const cond)
+{
+  const ThreadId vg_tid = VG_(get_running_tid)();
+  const DrdThreadId drd_tid = VgThreadIdToDrdThreadId(vg_tid);
+  struct cond_info* const cond_p = cond_get(cond);
+#if 0
+  VG_(message)(Vg_DebugMsg, "cond_pre_signal cond %d, w.c. %d, mutex %d",
+               cond,
+               cond_p ? cond_p->waiter_count : 0,
+               cond_p ? cond_p->mutex : 0);
+#endif
+  if (cond_p && cond_p->waiter_count > 0)
+  {
+    if (! mutex_is_locked_by(cond_p->mutex, drd_tid))
+    {
+      CondRaceErrInfo cei;
+      cei.cond  = cond;
+      cei.mutex = cond_p->mutex;
+      VG_(maybe_record_error)(vg_tid,
+                              CondRaceErr,
+                              VG_(get_IP)(vg_tid),
+                              "CondErr",
+                              &cei);
+    }
+  }
+  else
+  {
+    /* No other thread is waiting for the signal, hence the signal will be */
+    /* lost. This is normal in a POSIX threads application.                */
+  }
+}
+
+void cond_pre_broadcast(Addr const cond)
+{
+  cond_pre_signal(cond);
+}
+
+void cond_stop_using_mem(const Addr a1, const Addr a2)
+{
+  unsigned i;
+  for (i = 0; i < sizeof(s_cond)/sizeof(s_cond[0]); i++)
+  {
+    if (a1 <= s_cond[i].cond && s_cond[i].cond < a2)
+    {
+      tl_assert(s_cond[i].cond + PTHREAD_COND_SIZE <= a2);
+      cond_destroy(&s_cond[i]);
+    }
+  }
+}