Update and install proc_service.h [BZ #20311]

This adds an include guard and __BEGIN/__END_DECLS to proc_service.h,
removes some extraneous "const"s, and then arranges to install the
header.  The idea here is to make it more convenient to implement the
proc_service.h API.

ChangeLog

@@ -1,3 +1,14 @@
+2016-08-03  Tom Tromey  <tom@tromey.com>
+
+	[BZ #20311]
+	* nptl_db/Makefile (headers): Add proc_service.h.
+	* nptl_db/proc_service.h: Add include guard.  Use
+	__BEGIN/__END_DECLS.
+	(ps_get_thread_area, ps_pstop, ps_pcontinue, ps_lstop)
+	(ps_lcontinue): Remove "const" from "struct ps_prochandle *"
+	arguments.
+
+
 2016-08-03  Florian Weimer  <fweimer@redhat.com>
 
 	[BZ #17730]

nptl_db/Makefile

@@ -26,7 +26,7 @@ nptl_db-version = 1.0
 extra-libs = libthread_db
 extra-libs-others := $(extra-libs)
 
-headers         = thread_db.h sys/procfs.h
+headers         = proc_service.h thread_db.h sys/procfs.h
 
 libthread_db-routines = td_init td_log td_ta_new td_ta_delete \
 			td_ta_get_nthreads td_ta_get_ph \

nptl_db/proc_service.h

@@ -16,9 +16,14 @@
    License along with the GNU C Library; if not, see
    <http://www.gnu.org/licenses/>.  */
 
+#ifndef _PROC_SERVICE_H
+#define _PROC_SERVICE_H 1
+
 /* The definitions in this file must correspond to those in the debugger.  */
 #include <sys/procfs.h>
 
+__BEGIN_DECLS
+
 /* Functions in this interface return one of these status codes.  */
 typedef enum
 {
@@ -64,7 +69,7 @@ extern pid_t ps_getpid (struct ps_prochandle *);
 /* Fetch the special per-thread address associated with the given LWP.
    This call is only used on a few platforms (most use a normal register).
    The meaning of the `int' parameter is machine-dependent.  */
-extern ps_err_e ps_get_thread_area (const struct ps_prochandle *,
+extern ps_err_e ps_get_thread_area (struct ps_prochandle *,
 				    lwpid_t, int, psaddr_t *);
 
 
@@ -78,9 +83,13 @@ extern ps_err_e ps_pglobal_lookup (struct ps_prochandle *,
 
 
 /* Stop or continue the entire process.  */
-extern ps_err_e ps_pstop (const struct ps_prochandle *);
-extern ps_err_e ps_pcontinue (const struct ps_prochandle *);
+extern ps_err_e ps_pstop (struct ps_prochandle *);
+extern ps_err_e ps_pcontinue (struct ps_prochandle *);
 
 /* Stop or continue the given LWP alone.  */
-extern ps_err_e ps_lstop (const struct ps_prochandle *, lwpid_t);
-extern ps_err_e ps_lcontinue (const struct ps_prochandle *, lwpid_t);
+extern ps_err_e ps_lstop (struct ps_prochandle *, lwpid_t);
+extern ps_err_e ps_lcontinue (struct ps_prochandle *, lwpid_t);
+
+__END_DECLS
+
+#endif /* proc_service.h */