Add Semaphore facility to synchronize different treads in the tester

with each other.



git-svn-id: http://www.varnish-cache.org/svn/trunk/varnish-cache@2915 d4fa192b-c00b-0410-8231-f00ffab90ce4

bin/varnishtest/Makefile.am

@@ -10,6 +10,7 @@ varnishtest_SOURCES = \
 		vtc_client.c \
 		vtc_http.c \
 		vtc_log.c \
+		vtc_sema.c \
 		vtc_server.c \
 		vtc_varnish.c
 

bin/varnishtest/vtc.c

@@ -283,6 +283,7 @@ static struct cmds cmds[] = {
 	{ "delay", 	cmd_delay },
 	{ "test", 	cmd_test },
 	{ "shell", 	cmd_shell },
+	{ "sema", 	cmd_sema },
 	{ NULL, 	NULL }
 };
 
@@ -328,6 +329,7 @@ main(int argc, char * const *argv)
 	}
 	argc -= optind;
 	argv += optind;
+	init_sema();
 	for (ch = 0; ch < argc; ch++)
 		exec_file(argv[ch]);
 	fok = fopen("_.ok", "w");

bin/varnishtest/vtc.h

@@ -46,6 +46,9 @@ cmd_f cmd_server;
 cmd_f cmd_client;
 cmd_f cmd_stats;
 cmd_f cmd_varnish;
+cmd_f cmd_sema;
+
+void init_sema(void);
 
 void http_process(struct vtclog *vl, const char *spec, int sock, int client);
 

bin/varnishtest/vtc_http.c

@@ -606,6 +606,7 @@ static struct cmds http_cmds[] = {
 	{ "send",	cmd_http_send },
 	{ "chunked",	cmd_http_chunked },
 	{ "delay",	cmd_delay },
+	{ "sema",	cmd_sema },
 	{ NULL,		NULL }
 };
 

bin/varnishtest/vtc_sema.c

+/*
+ * Copyright (c) 2006-2008 Linpro AS
+ * All rights reserved.
+ * 
+ * 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.
+ *
+ * $Id: vtc_sema.c 2906 2008-07-08 10:29:07Z phk $
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include <pthread.h>
+
+#include "vtc.h"
+
+#include "vqueue.h"
+#include "miniobj.h"
+#include "libvarnish.h"
+
+struct sema {
+	unsigned		magic;
+#define SEMA_MAGIC		0x29b64317
+	char			*name;
+	struct vtclog		*vl;
+	VTAILQ_ENTRY(sema)	list;
+	pthread_mutex_t		mtx;
+	pthread_cond_t		cond;
+
+	unsigned		waiters;
+	unsigned		expected;
+};
+
+static pthread_mutex_t		sema_mtx;
+static VTAILQ_HEAD(, sema)	semas = VTAILQ_HEAD_INITIALIZER(semas);
+
+/**********************************************************************
+ * Allocate and initialize a sema
+ */
+
+static struct sema *
+sema_new(char *name)
+{
+	struct sema *r;
+
+	ALLOC_OBJ(r, SEMA_MAGIC);
+	AN(r);
+	r->vl = vtc_logopen(name);
+	AN(r->vl);
+	r->name = name;
+	if (*name != 'r')
+		vtc_log(r->vl, 0, "Sema name must start with 'r'");
+
+	AZ(pthread_mutex_init(&r->mtx, NULL));
+	AZ(pthread_cond_init(&r->cond, NULL));
+	r->waiters = 0;
+	r->expected = 0;
+	VTAILQ_INSERT_TAIL(&semas, r, list);
+	return (r);
+}
+
+/**********************************************************************
+ * Sync a sema
+ */
+
+static void
+sema_sync(struct sema *r, const char *av)
+{
+	unsigned u;
+
+	u = strtoul(av, NULL, 0);
+
+	AZ(pthread_mutex_lock(&r->mtx));
+	if (r->expected == 0)
+		r->expected = u;
+	assert(r->expected == u);
+
+	if (++r->waiters == r->expected) {
+		vtc_log(r->vl, 4, "Wake %u", r->expected);
+		AZ(pthread_cond_broadcast(&r->cond));
+		r->waiters = 0;
+		r->expected = 0;
+	} else 
+		AZ(pthread_cond_wait(&r->cond, &r->mtx));
+	AZ(pthread_mutex_unlock(&r->mtx));
+}
+
+/**********************************************************************
+ * Semaphore command dispatch
+ */
+
+void
+cmd_sema(CMD_ARGS)
+{
+	struct sema *r, *r2;
+
+	(void)priv;
+	(void)cmd;
+
+	if (av == NULL) {
+		AZ(pthread_mutex_lock(&sema_mtx));
+		/* Reset and free */
+		VTAILQ_FOREACH_SAFE(r, &semas, list, r2) {
+			VTAILQ_REMOVE(&semas, r, list);
+			FREE_OBJ(r);
+			/* XXX: MEMLEAK */
+		}
+		AZ(pthread_mutex_unlock(&sema_mtx));
+		return;
+	}
+
+	assert(!strcmp(av[0], "sema"));
+	av++;
+
+	AZ(pthread_mutex_lock(&sema_mtx));
+	VTAILQ_FOREACH(r, &semas, list)
+		if (!strcmp(r->name, av[0]))
+			break;
+	if (r == NULL) 
+		r = sema_new(av[0]);
+	AZ(pthread_mutex_unlock(&sema_mtx));
+	av++;
+
+	for (; *av != NULL; av++) {
+		if (!strcmp(*av, "sync")) {
+			av++;
+			AN(*av);
+			sema_sync(r, *av);
+			continue;
+		}
+		vtc_log(r->vl, 0, "Unknown sema argument: %s", *av);
+	}
+}
+
+void
+init_sema(void)
+{
+	AZ(pthread_mutex_init(&sema_mtx, NULL));
+}