Add a SIGINFO handler for dtrace(1).

Have it print the contents of aggregations, if any. Otherwise, one needs to
kill the running script to view the collected data, or add code to
periodically print it.

Discussed with:	gnn
MFC after:	1 month

1 files changed, 25 insertions, 1 deletions

diff --git a/cddl/contrib/opensolaris/cmd/dtrace/dtrace.c b/cddl/contrib/opensolaris/cmd/dtrace/dtrace.c
index d065cdc180a4..5b291e4ff304 100644
--- a/cddl/contrib/opensolaris/cmd/dtrace/dtrace.c
+++ b/cddl/contrib/opensolaris/cmd/dtrace/dtrace.c
@@ -93,6 +93,9 @@ static int g_flowindent;
 static int g_intr;
 static int g_impatient;
 static int g_newline;
+#ifdef __FreeBSD__
+static int g_siginfo;
+#endif
 static int g_total;
 static int g_cflags;
 static int g_oflags;
@@ -1260,6 +1263,16 @@ intr(int signo)
 		g_impatient = 1;
 }
 
+#ifdef __FreeBSD__
+static void
+siginfo(int signo __unused)
+{
+
+	g_siginfo++;
+	g_newline = 1;
+}
+#endif
+
 static void
 installsighands(void)
 {
@@ -1275,12 +1288,16 @@ installsighands(void)
 	if (sigaction(SIGTERM, NULL, &oact) == 0 && oact.sa_handler != SIG_IGN)
 		(void) sigaction(SIGTERM, &act, NULL);
 
-#ifndef illumos
+#ifdef __FreeBSD__
 	if (sigaction(SIGPIPE, NULL, &oact) == 0 && oact.sa_handler != SIG_IGN)
 		(void) sigaction(SIGPIPE, &act, NULL);
 
 	if (sigaction(SIGUSR1, NULL, &oact) == 0 && oact.sa_handler != SIG_IGN)
 		(void) sigaction(SIGUSR1, &act, NULL);
+
+	act.sa_handler = siginfo;
+	if (sigaction(SIGINFO, NULL, &oact) == 0 && oact.sa_handler != SIG_IGN)
+		(void) sigaction(SIGINFO, &act, NULL);
 #endif
 }
 
@@ -1944,6 +1961,13 @@ main(int argc, char *argv[])
 		if (!g_intr && !done)
 			dtrace_sleep(g_dtp);
 
+#ifdef __FreeBSD__
+		if (g_siginfo) {
+			(void)dtrace_aggregate_print(g_dtp, g_ofp, NULL);
+			g_siginfo = 0;
+		}
+#endif
+
 		if (g_newline) {
 			/*
 			 * Output a newline just to make the output look