[PATCH 03/12] gdbsupport: add type definitions for pid, lwp and tid

[Simon Marchi <simon.marchi@efficios.com>]

A following patch will want to declare variables of the same time as
some ptid_t components.  To make that easy (and avoid harcoding those
types everywhere), define some type definitions in the ptid_t struct for
each of them.  Use them throughout ptid.h.

I initially used pid_t, lwp_t and tid_t, but there is the risk of some
system defining the pid_t type using a macro instead of a typedef, which
would break things.  So, use the _type suffix instead.

Change-Id: I820b0bea9dafcb4914f1c9ba4bb96b5c666c8dec
---
 gdbsupport/ptid.h | 18 +++++++++++-------
 1 file changed, 11 insertions(+), 7 deletions(-)

diff --git a/gdbsupport/ptid.h b/gdbsupport/ptid.h
index d66cd988459..6dcab984b99 100644
--- a/gdbsupport/ptid.h
+++ b/gdbsupport/ptid.h
@@ -39,6 +39,10 @@
 class ptid_t
 {
 public:
+  using pid_type = int;
+  using lwp_type = long;
+  using tid_type = ULONGEST;
+
   /* Must have a trivial defaulted default constructor so that the
      type remains POD.  */
   ptid_t () noexcept = default;
@@ -48,13 +52,13 @@ class ptid_t
      A ptid with only a PID (LWP and TID equal to zero) is usually used to
      represent a whole process, including all its lwps/threads.  */
 
-  explicit constexpr ptid_t (int pid, long lwp = 0, ULONGEST tid = 0)
+  explicit constexpr ptid_t (pid_type pid, lwp_type lwp = 0, tid_type tid = 0)
     : m_pid (pid), m_lwp (lwp), m_tid (tid)
   {}
 
   /* Fetch the pid (process id) component from the ptid.  */
 
-  constexpr int pid () const
+  constexpr pid_type pid () const
   { return m_pid; }
 
   /* Return true if the ptid's lwp member is non-zero.  */
@@ -64,7 +68,7 @@ class ptid_t
 
   /* Fetch the lwp (lightweight process) component from the ptid.  */
 
-  constexpr long lwp () const
+  constexpr lwp_type lwp () const
   { return m_lwp; }
 
   /* Return true if the ptid's tid member is non-zero.  */
@@ -74,7 +78,7 @@ class ptid_t
 
   /* Fetch the tid (thread id) component from a ptid.  */
 
-  constexpr ULONGEST tid () const
+  constexpr tid_type tid () const
   { return m_tid; }
 
   /* Return true if the ptid represents a whole process, including all its
@@ -144,13 +148,13 @@ class ptid_t
 
 private:
   /* Process id.  */
-  int m_pid;
+  pid_type m_pid;
 
   /* Lightweight process id.  */
-  long m_lwp;
+  lwp_type m_lwp;
 
   /* Thread id.  */
-  ULONGEST m_tid;
+  tid_type m_tid;
 };
 
 /* Functor to hash a ptid.  */
-- 
2.38.1