When cross-compiling, we cannot run a test program to check whether a siginfo_t provides the signal sender PID, so we fall back to assuming that it does, and also check that SA_SIGINFO is declared so compilation will not fail on systems without it (#120).

src/include/config-aux.h

@@ -43,3 +43,11 @@ typedef bool _Bool;
 # define true 1
 # define __bool_true_false_are_defined 1
 #endif
+
+/* Whether "--remote" should be available. */
+#undef PV_REMOTE_CONTROL
+#if HAVE_DECL_SA_SIGINFO
+# if SIGINFO_PROVIDES_PID
+#define PV_REMOTE_CONTROL 1
+# endif
+#endif

src/include/config.h.in

@@ -28,6 +28,10 @@
    */
 #undef HAVE_DCGETTEXT
 
+/* Define to 1 if you have the declaration of `SA_SIGINFO', and to 0 if you
+   don't. */
+#undef HAVE_DECL_SA_SIGINFO
+
 /* Define to 1 if you have the `dup2' function. */
 #undef HAVE_DUP2
 

src/include/pv-internal.h

@@ -159,13 +159,13 @@ struct pvstate_s {
 		struct sigaction old_sigint;
 		struct sigaction old_sighup;
 		struct sigaction old_sigterm;
-#ifdef SIGINFO_PROVIDES_PID
+#ifdef PV_REMOTE_CONTROL
 		struct sigaction old_sigusr2;
 #endif
 		struct sigaction old_sigalrm;
 		struct timespec tstp_time;	 /* see pv_sig_tstp() / __cont() */
 		struct timespec toffset;	 /* total time spent stopped */
-#ifdef SIGINFO_PROVIDES_PID
+#ifdef PV_REMOTE_CONTROL
 		volatile sig_atomic_t rxusr2;	 /* whether SIGUSR2 was received */
 		volatile pid_t sender;		 /* PID of sending process for SIGUSR2 */
 #endif

src/include/pv.h

@@ -238,7 +238,7 @@ extern off_t pv_calc_total_size(pvstate_t);
  */
 extern void pv_sig_init(pvstate_t);
 
-#ifdef SIGINFO_PROVIDES_PID
+#ifdef PV_REMOTE_CONTROL
 /*
  * Return true if SIGUSR2 has been received, and indicate the sender.
  */