Renovate libvarnisapi signal handling.

Introduce VSIG which simply counts number of signals, which everybody
else can then look at.

If you use libvarnishapi and want your own signal handler, you must
increment these VSIG_{int|hup|term|usr1} counters yourself, for
libvarnishapi to work correctly.

The old VUT_Signal()/VUT_Signaled() API is retained and should be
deprecated in a future version.

Inspired by:	#2818

bin/varnishhist/varnishhist.c

@@ -371,14 +371,6 @@ accumulate(struct VSL_data *vsl, struct VSL_transaction * const pt[],
 	return (0);
 }
 
-static int v_matchproto_(VUT_cb_f)
-sighup(struct VUT *v)
-{
-	assert(v == vut);
-	quit = 1;
-	return (1);
-}
-
 static void * v_matchproto_(pthread_t)
 do_curses(void *arg)
 {
@@ -392,7 +384,7 @@ do_curses(void *arg)
 	intrflush(stdscr, FALSE);
 	curs_set(0);
 	erase();
-	while (!quit) {
+	while (!quit && !vut->last_sighup) {
 		AZ(pthread_mutex_lock(&mtx));
 		update();
 		AZ(pthread_mutex_unlock(&mtx));
@@ -480,14 +472,6 @@ profile_error(const char *s)
 	exit(1);
 }
 
-static void
-vut_sighandler(int sig)
-{
-
-	if (vut != NULL)
-		VUT_Signaled(vut, sig);
-}
-
 int
 main(int argc, char **argv)
 {
@@ -638,7 +622,6 @@ main(int argc, char **argv)
 
 	log_ten = log(10.0);
 
-	VUT_Signal(vut_sighandler);
 	VUT_Setup(vut);
 	if (vut->vsm)
 		ident = VSM_Dup(vut->vsm, "Arg", "-i");
@@ -647,7 +630,6 @@ main(int argc, char **argv)
 	AZ(pthread_create(&thr, NULL, do_curses, NULL));
 	vut->dispatch_f = accumulate;
 	vut->dispatch_priv = NULL;
-	vut->sighup_f = sighup;
 	(void)VUT_Main(vut);
 	end_of_file = 1;
 	AZ(pthread_join(thr, NULL));

bin/varnishlog/varnishlog.c

@@ -32,6 +32,7 @@
 
 #include "config.h"
 
+#include <signal.h>
 #include <stdarg.h>
 #include <stdlib.h>
 #include <stdio.h>
@@ -102,21 +103,6 @@ flushout(struct VUT *v)
 	return (0);
 }
 
-static int v_matchproto_(VUT_cb_f)
-sighup(struct VUT *v)
-{
-	assert(v == vut);
-	return (1);
-}
-
-static void
-vut_sighandler(int sig)
-{
-
-	if (vut != NULL)
-		VUT_Signaled(vut, sig);
-}
-
 int
 main(int argc, char * const *argv)
 {
@@ -160,7 +146,6 @@ main(int argc, char * const *argv)
 		vut->dispatch_f = VSL_PrintTransactions;
 	else
 		vut->dispatch_f = VSL_WriteTransactions;
-	vut->sighup_f = sighup;
 	if (LOG.w_arg) {
 		openout(LOG.a_opt);
 		AN(LOG.fo);
@@ -170,7 +155,6 @@ main(int argc, char * const *argv)
 		LOG.fo = stdout;
 	vut->idle_f = flushout;
 
-	VUT_Signal(vut_sighandler);
 	VUT_Setup(vut);
 	(void)VUT_Main(vut);
 	VUT_Fini(&vut);

bin/varnishncsa/varnishncsa.c

@@ -1050,21 +1050,6 @@ dispatch_f(struct VSL_data *vsl, struct VSL_transaction * const pt[],
 	return (0);
 }
 
-static int v_matchproto_(VUT_cb_f)
-sighup(struct VUT *v)
-{
-	assert(v == vut);
-	return (1);
-}
-
-static void
-vut_sighandler(int sig)
-{
-
-	if (vut != NULL)
-		VUT_Signaled(vut, sig);
-}
-
 static char *
 read_format(const char *formatfile)
 {
@@ -1175,7 +1160,6 @@ main(int argc, char * const *argv)
 	/* Setup output */
 	vut->dispatch_f = dispatch_f;
 	vut->dispatch_priv = NULL;
-	vut->sighup_f = sighup;
 	if (CTX.w_arg) {
 		openout(CTX.a_opt);
 		AN(CTX.fo);
@@ -1185,7 +1169,6 @@ main(int argc, char * const *argv)
 		CTX.fo = stdout;
 	vut->idle_f = flushout;
 
-	VUT_Signal(vut_sighandler);
 	VUT_Setup(vut);
 	(void)VUT_Main(vut);
 	VUT_Fini(&vut);

bin/varnishtop/varnishtop.c

@@ -182,22 +182,6 @@ accumulate(struct VSL_data *vsl, struct VSL_transaction * const pt[],
 	return (0);
 }
 
-static int v_matchproto_(VUT_cb_f)
-sighup(struct VUT *v)
-{
-	assert(v == vut);
-	quit = 1;
-	return (1);
-}
-
-static void
-vut_sighandler(int sig)
-{
-
-	if (vut != NULL)
-		VUT_Signaled(vut, sig);
-}
-
 static void
 update(int p)
 {
@@ -273,7 +257,7 @@ do_curses(void *arg)
 	(void)curs_set(0);
 	AC(erase());
 	timeout(1000);
-	while (!quit) {
+	while (!quit && !vut->last_sighup) {
 		AZ(pthread_mutex_lock(&mtx));
 		update(period);
 		AZ(pthread_mutex_unlock(&mtx));
@@ -364,7 +348,6 @@ main(int argc, char **argv)
 	if (optind != argc)
 		VUT_Usage(vut, &vopt_spec, 1);
 
-	VUT_Signal(vut_sighandler);
 	VUT_Setup(vut);
 	if (vut->vsm)
 		ident = VSM_Dup(vut->vsm, "Arg", "-i");
@@ -372,7 +355,6 @@ main(int argc, char **argv)
 		ident = strdup("");
 	vut->dispatch_f = accumulate;
 	vut->dispatch_priv = NULL;
-	vut->sighup_f = sighup;
 	if (once) {
 		(void)VUT_Main(vut);
 		dump();

include/Makefile.am

@@ -39,13 +39,15 @@ nobase_pkginclude_HEADERS = \
 	tbl/vhp_static.h \
 	tbl/vrt_stv_var.h \
 	tbl/vsc_levels.h \
+	tbl/vsig_list.h \
 	tbl/vsl_tags.h \
 	tbl/vsl_tags_http.h \
 	tbl/waiters.h \
-	vapi/vsm.h \
 	vapi/vsc.h \
+	vapi/vsig.h \
 	vapi/vsl.h \
 	vapi/vsl_int.h \
+	vapi/vsm.h \
 	vapi/voptget.h \
 	vapi/vapi_options.h \
 	vcli.h \

include/tbl/vsig_list.h

+/*-
+ * Copyright (c) 2018 Varnish Software AS
+ * All rights reserved.
+ *
+ * Author: Poul-Henning Kamp <phk@phk.freebsd.dk>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * NB: Changing the list of signals requires updating libvarnishapi.map
+ *
+ */
+
+/*lint -save -e525 -e539 */
+
+VSIG_SIGNAL(INT,	int)
+VSIG_SIGNAL(HUP,	hup)
+VSIG_SIGNAL(TERM,	term)
+VSIG_SIGNAL(USR1,	usr1)
+#undef VSIG_SIGNAL
+
+/*lint -restore */

include/vapi/vsig.h

+/*-
+ * Copyright (c) 2018 Varnish Software AS
+ * All rights reserved.
+ *
+ * Author: Poul-Henning Kamp <phk@phk.freebsd.dk>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ */
+
+#ifndef VAPI_VSIG_H_INCLUDED
+#define VAPI_VSIG_H_INCLUDED
+
+#define VSIG_SIGNAL(UPPER, lower)		\
+	extern sig_atomic_t VSIG_##lower;	\
+	void VSIG_Got_##lower(int sig);		\
+	void VSIG_Arm_##lower(void);
+
+#include "tbl/vsig_list.h"
+
+#endif /* VAPI_VSC_H_INCLUDED */

include/vut.h

@@ -56,9 +56,9 @@ struct VUT {
 	struct VSL_data	*vsl;
 	struct vsm	*vsm;
 	struct VSLQ	*vslq;
-	int		sighup;
-	int		sigint;
-	int		sigusr1;
+
+	sig_atomic_t	last_sighup;
+	sig_atomic_t	last_sigusr1;
 
 	/* Callback functions */
 	VUT_cb_f	*idle_f;

lib/libvarnishapi/Makefile.am

@@ -31,18 +31,19 @@ libvarnishapi_la_SOURCES = \
 	../libvarnish/vtim.c \
 	../libvarnish/vnum.c \
 	../libvarnish/vsha256.c \
-	vsm.c \
+	vsc.c \
+	vsig.c \
+	vsl.c \
 	vsl_arg.c \
 	vsl_cursor.c \
 	vsl_dispatch.c \
 	vsl_query.c \
-	vsl.c \
-	vsc.c \
+	vsm.c \
 	vut.c \
 	vxp.c \
-	vxp_parse.c \
-	vxp_lexer.c \
 	vxp_fixed_token.c \
+	vxp_lexer.c \
+	vxp_parse.c \
 	libvarnishapi.map
 
 if ! HAVE_DAEMON

lib/libvarnishapi/libvarnishapi.map

@@ -148,3 +148,22 @@ LIBVARNISHAPI_2.1 {
     local:
 	*;
 };
+
+LIBVARNISHAPI_2.2 {
+    global:
+	# vsig.c
+	VSIG_int;
+	VSIG_Got_int;
+	VSIG_Arm_int;
+	VSIG_hup;
+	VSIG_Got_hup;
+	VSIG_Arm_hup;
+	VSIG_term;
+	VSIG_Got_term;
+	VSIG_Arm_term;
+	VSIG_usr1;
+	VSIG_Got_usr1;
+	VSIG_Arm_usr1;
+    local:
+	*;
+};

lib/libvarnishapi/vsig.c

+/*-
+ * Copyright (c) 2018 Varnish Software AS
+ * All rights reserved.
+ *
+ * Author: Poul-Henning Kamp <phk@phk.freebsd.dk>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * Common functions for the utilities
+ */
+
+#include "config.h"
+
+#include <signal.h>
+
+#include "vapi/vsig.h"
+
+#define VSIG_SIGNAL(UPPER, lower)				\
+	sig_atomic_t VSIG_##lower;
+#include "tbl/vsig_list.h"
+
+#define VSIG_SIGNAL(UPPER, lower)				\
+	void							\
+	VSIG_Got_##lower(int sig)				\
+	{							\
+		(void)sig;					\
+		VSIG_##lower++;					\
+	}
+#include "tbl/vsig_list.h"
+
+#define VSIG_SIGNAL(UPPER, lower)				\
+	void							\
+	VSIG_Arm_##lower(void)					\
+	{							\
+		(void)signal(SIG##UPPER, VSIG_Got_##lower);	\
+	}
+#include "tbl/vsig_list.h"

lib/libvarnishapi/vut.c

@@ -54,6 +54,7 @@
 #include "vut.h"
 
 #include "vapi/voptget.h"
+#include "vapi/vsig.h"
 
 static int vut_synopsis(const struct vopt_spec *);
 static int vut_options(const struct vopt_spec *);
@@ -206,6 +207,11 @@ VUT_Init(const char *progname, int argc, char * const *argv,
 	AN(argv);
 	AN(voc);
 
+	VSIG_Arm_hup();
+	VSIG_Arm_int();
+	VSIG_Arm_term();
+	VSIG_Arm_usr1();
+
 	ALLOC_OBJ(vut, VUT_MAGIC);
 	AN(vut);
 
@@ -243,9 +249,9 @@ VUT_Signaled(struct VUT *vut, int sig)
 {
 
 	CHECK_OBJ_NOTNULL(vut, VUT_MAGIC);
-	vut->sighup |= (int)(sig == SIGHUP);
-	vut->sigint |= (int)(sig == SIGINT || sig == SIGTERM);
-	vut->sigusr1 |= (int)(sig == SIGUSR1);
+#define VSIG_SIGNAL(UPPER, lower) \
+	VSIG_##lower += (int)(sig == SIG##UPPER);
+#include "tbl/vsig_list.h"
 }
 
 void
@@ -353,18 +359,21 @@ VUT_Main(struct VUT *vut)
 	CHECK_OBJ_NOTNULL(vut, VUT_MAGIC);
 	AN(vut->vslq);
 
-	while (!vut->sigint) {
-		if (vut->sighup && vut->sighup_f) {
+	while (!VSIG_int && !VSIG_term) {
+		if (VSIG_hup != vut->last_sighup) {
 			/* sighup callback */
-			vut->sighup = 0;
-			i = vut->sighup_f(vut);
+			vut->last_sighup = VSIG_hup;
+			if (vut->sighup_f != NULL)
+				i = vut->sighup_f(vut);
+			else
+				i = 1;
 			if (i)
 				break;
 		}
 
-		if (vut->sigusr1) {
+		if (VSIG_usr1 != vut->last_sigusr1) {
 			/* Flush and report any incomplete records */
-			vut->sigusr1 = 0;
+			vut->last_sigusr1 = VSIG_usr1;
 			(void)VSLQ_Flush(vut->vslq, vut_dispatch, vut);
 		}
 
@@ -412,7 +421,7 @@ VUT_Main(struct VUT *vut)
 
 		do
 			i = VSLQ_Dispatch(vut->vslq, vut_dispatch, vut);
-		while (i == vsl_more && !vut->sighup && !vut->sigusr1);
+		while (i == vsl_more && !VSIG_hup && !VSIG_usr1);
 
 		if (i == vsl_more)
 			continue;