adaint.c: Add function __gnat_lwp_self that retrieves the LWP of the current thread.

2009-04-15  Nicolas Roche  <roche@adacore.com>

	* adaint.c: Add function __gnat_lwp_self that retrieves the LWP of the
	current thread.

	* s-osinte-linux.ads: Import the __gnat_lwp_self function as lwp_self

	* s-taprop-linux.adb (Enter_Task): Store the LWP in the TCB

From-SVN: r146097

gcc/ada/ChangeLog

+2009-04-15  Nicolas Roche  <roche@adacore.com>
+
+	* adaint.c: Add function __gnat_lwp_self that retrieves the LWP of the
+	current thread.
+
+	* s-osinte-linux.ads: Import the __gnat_lwp_self function as lwp_self
+
+	* s-taprop-linux.adb (Enter_Task): Store the LWP in the TCB
+
 2009-04-15  Ed Schonberg  <schonberg@adacore.com>
 
 	* sem_ch4.adb: improve error message on exponentiation.

gcc/ada/adaint.c

@@ -3346,3 +3346,13 @@ __gnat_pthread_setaffinity_np (pthread_t th ATTRIBUTE_UNUSED,
 }
 #endif
 #endif
+
+#if defined (linux)
+/* There is no function in the glibc to retrieve the LWP of the current
+   thread. We need to do a system call in order to retrieve this
+   information. */
+#include <sys/syscall.h>
+void *__gnat_lwp_self (void) {
+   return (void *) syscall (__NR_gettid);
+}
+#endif

gcc/ada/s-osinte-linux.ads

@@ -464,6 +464,9 @@ package System.OS_Interface is
    function pthread_self return pthread_t;
    pragma Import (C, pthread_self, "pthread_self");
 
+   function lwp_self return System.Address;
+   pragma Import (C, lwp_self, "__gnat_lwp_self");
+
    --------------------------
    -- POSIX.1c  Section 17 --
    --------------------------

gcc/ada/s-taprop-linux.adb

@@ -701,6 +701,7 @@ package body System.Task_Primitives.Operations is
       end if;
 
       Self_ID.Common.LL.Thread := pthread_self;
+      Self_ID.Common.LL.LWP := lwp_self;
 
       Specific.Set (Self_ID);