New API for adding and removing IP addresses on the fly.

* src/config.c (cf_ip_list): Support both parse and serialize calls.
* src/ping903.c (/config/ip-list): New endpoint.  PUT to add a host
or IP to the ip-list, DELETE to remove existing one.
* src/ping903.h (hostping_add_name)
(hostping_add_name,get_all_hosts): New protos.
* src/pinger.c: Protect each iteration over hostping list by a
rwlock object.
(hostping_delete,get_all_hosts)
(hostping_delete_by_name)
(hostping_add_name): New functions.

4 files changed, 218 insertions, 27 deletions

diff --git a/src/config.c b/src/config.c
index e8b2f36..f2376a5 100644
--- a/src/config.c
+++ b/src/config.c
@@ -44,7 +44,7 @@ get_num(char const *str, unsigned long *retval,
 }
 
 static int
-cf_ip_list(int mode, union cf_callback_arg *arg, void *data)
+cf_ip_list_parse(union cf_callback_arg *arg, void *data)
 {
 	FILE *fp;
 	char buf[1024];
@@ -53,9 +53,6 @@ cf_ip_list(int mode, union cf_callback_arg *arg, void *data)
 	int ret = CF_RET_OK;
 	struct addrinfo hints;
 
-	if (mode != CF_PARSE)
-		return CF_RET_IGNORE;
-	
 	fp = fopen(arg->input.val, "r");
 	if (!fp) {
 		error("%s:%d: can't open file %s: %s",
@@ -115,6 +112,25 @@ cf_ip_list(int mode, union cf_callback_arg *arg, void *data)
 	fclose(fp);
 	return ret;
 }
+
+static int
+cf_ip_list_serialize(union cf_callback_arg *arg, void *data)
+{
+	if (get_all_hosts(&arg->output))
+		return CF_RET_FAIL;
+	return CF_RET_OK;
+}
+
+static int
+cf_ip_list(int mode, union cf_callback_arg *arg, void *data)
+{
+	switch (mode) {
+	case CF_PARSE:
+		return cf_ip_list_parse(arg, data);
+	case CF_SERIALIZE:
+		return cf_ip_list_serialize(arg, data);
+	}
+}
 
 struct cf_stmt {
 	char const *kw;
diff --git a/src/ping903.c b/src/ping903.c
index bda2314..efc6246 100644
--- a/src/ping903.c
+++ b/src/ping903.c
@@ -298,6 +298,52 @@ ept_config(struct MHD_Connection *conn,
 }
 
 static int
+ept_ip_delete(struct MHD_Connection *conn,
+	      const char *url, const char *method, const char *suffix)
+{
+	int ret;
+	struct MHD_Response *resp;
+	
+	while (*suffix == '/')
+		suffix++;
+	if (!*suffix)
+		return http_error(conn, method, url, MHD_HTTP_FORBIDDEN);
+	if (hostping_delete_by_name(suffix))
+		return http_error(conn, method, url, MHD_HTTP_NOT_FOUND);
+		
+	resp = MHD_create_response_from_buffer(0,
+					       NULL,
+					       MHD_RESPMEM_PERSISTENT);
+	http_log(conn, method, url, MHD_HTTP_OK, NULL);
+	ret = MHD_queue_response(conn, MHD_HTTP_OK, resp);
+	MHD_destroy_response(resp);
+	return ret;
+}
+
+static int
+ept_ip_put(struct MHD_Connection *conn,
+	   const char *url, const char *method, const char *suffix)
+{
+	int ret;
+	struct MHD_Response *resp;
+	
+	while (*suffix == '/')
+		suffix++;
+	if (!*suffix)
+		return http_error(conn, method, url, MHD_HTTP_FORBIDDEN);
+	if (hostping_add_name(suffix))
+		//FIXME
+		return http_error(conn, method, url, MHD_HTTP_FORBIDDEN);
+	resp = MHD_create_response_from_buffer(0,
+					       NULL,
+					       MHD_RESPMEM_PERSISTENT);
+	http_log(conn, method, url, MHD_HTTP_CREATED, NULL);
+	ret = MHD_queue_response(conn, MHD_HTTP_CREATED, resp);
+	MHD_destroy_response(resp);
+	return ret;
+}
+
+static int
 ept_host_stat(struct MHD_Connection *conn,
 	      const char *url, const char *method, const char *suffix)
 {
@@ -402,7 +448,9 @@ struct endpoint {
 };
 
 static struct endpoint endpoint[] = {
-	{ "/config", EPT_PREFIX,  MHD_HTTP_METHOD_GET, ept_config },
+	{ "/config/ip-list", EPT_PREFIX, MHD_HTTP_METHOD_PUT, ept_ip_put },
+	{ "/config/ip-list", EPT_PREFIX, MHD_HTTP_METHOD_DELETE, ept_ip_delete },
+	{ "/config", EPT_PREFIX, MHD_HTTP_METHOD_GET, ept_config },
 	{ "/host",   EPT_PREFIX, MHD_HTTP_METHOD_GET, ept_host_stat },
 	{ "/ip",     EPT_PREFIX, MHD_HTTP_METHOD_GET, ept_ip_stat },
 	{ "/match",  EPT_PREFIX, MHD_HTTP_METHOD_GET, ept_ip_match },
diff --git a/src/ping903.h b/src/ping903.h
index d7ad922..2f2d7ef 100644
--- a/src/ping903.h
+++ b/src/ping903.h
@@ -59,6 +59,8 @@ int readconfig(char const *file);
 int cf_trusted_ip(int mode, union cf_callback_arg *arg, void *data);
 int cf_syslog_facility(int mode, union cf_callback_arg *arg, void *data);
 void hostping_add(char const *name, struct sockaddr *addr, socklen_t addrlen);
+int hostping_delete_by_name(char const *name);
+int hostping_add_name(char const *name);
 
 char *get_remote_ip(struct MHD_Connection *conn);
 
@@ -125,6 +127,7 @@ extern size_t data_length;
 struct json_value *config_to_json(void);
 int get_hostname_stat(char const *name, struct json_value **retval);
 int get_ipaddr_stat(struct sockaddr *sa, int salen, struct json_value **retval);
+int get_all_hosts(struct json_value **);
 int get_all_host_stat(struct json_value **);
 struct addrinfo;
 int get_host_matches(struct addrinfo **aip, struct json_value **retval);
diff --git a/src/pinger.c b/src/pinger.c
index 070cbe6..19572d5 100644
--- a/src/pinger.c
+++ b/src/pinger.c
@@ -99,6 +99,7 @@ timespec_incr(struct timespec *a, struct timespec const *b)
 
 static HOSTPING *hostping_head, *hostping_tail;
 static size_t hostping_count;
+static pthread_rwlock_t hostping_rwlock = PTHREAD_RWLOCK_INITIALIZER;
 
 void
 hostping_add(char const *name, struct sockaddr *addr, socklen_t addrlen)
@@ -123,6 +124,25 @@ hostping_add(char const *name, struct sockaddr *addr, socklen_t addrlen)
 	hostping_count++;
 }
 
+void
+hostping_delete(HOSTPING *hp)
+{
+	if (hp->prev)
+		hp->prev->next = hp->next;
+	else
+		hostping_head = hp->next;
+	if (hp->next)
+		hp->next->prev = hp->prev;
+	else
+		hostping_tail = hp->prev;
+	hostping_count--;
+
+	free(hp->name);
+	free(hp->addr);
+	pthread_mutex_destroy(&hp->mutex);
+	free(hp);
+}
+
 #define FOR_EACH_HOSTPING(hp) for (hp = hostping_head; hp; hp = hp->next)
 
 static inline void
@@ -315,26 +335,36 @@ int
 get_hostname_stat(char const *name, struct json_value **retval)
 {
 	HOSTPING *hp;
-
+	int rc = 0;
+	
+	*retval = NULL;
+	pthread_rwlock_rdlock(&hostping_rwlock);
 	FOR_EACH_HOSTPING(hp) {
-		if (strcmp(hp->name, name) == 0)
-			return get_hostping_stat(hp, retval);
+		if (strcmp(hp->name, name) == 0) {
+			rc = get_hostping_stat(hp, retval);
+			break;
+		}
 	}
-	*retval = NULL;
-	return 0;
+	pthread_rwlock_unlock(&hostping_rwlock);
+	return rc;
 }
 
 int
 get_ipaddr_stat(struct sockaddr *sa, int salen, struct json_value **retval)
 {
 	HOSTPING *hp;
-
+	int rc;
+	
+	*retval = NULL;
+	pthread_rwlock_rdlock(&hostping_rwlock);
 	FOR_EACH_HOSTPING(hp) {
 		if (hp->addrlen == salen
-		    && memcmp(hp->addr, sa, salen) == 0)
-			return get_hostping_stat(hp, retval);
+		    && memcmp(hp->addr, sa, salen) == 0) {
+			rc = get_hostping_stat(hp, retval);
+			break;
+		}
 	}
-	*retval = NULL;
+	pthread_rwlock_unlock(&hostping_rwlock);
 	return 0;
 }
 
@@ -343,23 +373,60 @@ get_all_host_stat(struct json_value **retval)
 {
 	struct json_value *ar;
 	HOSTPING *hp;
+	int rc = 0;
 	
 	if (!(ar = json_new_array()))
-		goto err;
+		return -1;
+	pthread_rwlock_rdlock(&hostping_rwlock);
 	FOR_EACH_HOSTPING(hp) {
 		struct json_value *v;
-		if (get_hostping_stat(hp, &v))
-			goto err;
+		if (get_hostping_stat(hp, &v)) {
+			rc = -1;
+			break;
+		}
 		if (json_array_append(ar, v)) {
 			json_value_free(v);
-			goto err;
+			rc = -1;
+			break;
 		}
 	}
-	*retval = ar;
-	return 0;
-  err:
-	json_value_free(ar);
-	return -1;
+	pthread_rwlock_unlock(&hostping_rwlock);
+	if (rc == 0)
+		*retval = ar;
+	else
+		json_value_free(ar);
+	return rc;
+}
+
+int
+get_all_hosts(struct json_value **retval)
+{
+	struct json_value *ar;
+	HOSTPING *hp;
+	int rc = 0;
+	
+	if (!(ar = json_new_array()))
+		return -1;
+	pthread_rwlock_rdlock(&hostping_rwlock);
+	FOR_EACH_HOSTPING(hp) {
+		struct json_value *jv;
+		jv = json_new_string(hp->name);
+		if (!jv) {
+			rc = -1;
+			break;
+		}
+		if (json_array_append(ar, jv)) {
+			json_value_free(jv);
+			rc = -1;
+			break;
+		}
+	}
+	pthread_rwlock_unlock(&hostping_rwlock);
+	if (rc == 0)
+		*retval = ar;
+	else
+		json_value_free(ar);
+	return rc;
 }
 
 int 
@@ -372,7 +439,8 @@ get_host_matches(struct addrinfo **aip, struct json_value **retval)
 	int ret = -1;
 	
 	if (!(ar = json_new_array()))
-		goto err;
+		return -1;
+	pthread_rwlock_rdlock(&hostping_rwlock);
 	FOR_EACH_HOSTPING(hp) {
 		struct addrinfo *prev = NULL, *p;
 		if (!ai)
@@ -417,6 +485,7 @@ get_host_matches(struct addrinfo **aip, struct json_value **retval)
 	*retval = ar;
 	ar = NULL;
 err:	
+	pthread_rwlock_unlock(&hostping_rwlock);
 	if (ai_tail) {
 		ai_tail->ai_next = ai;
 		*aip = ai_head;
@@ -424,6 +493,57 @@ err:
 	json_value_free(ar);
 	return ret;
 }
+
+int
+hostping_delete_by_name(char const *name)
+{
+	HOSTPING *hp;
+	int rc = -1;
+	
+	pthread_rwlock_wrlock(&hostping_rwlock);
+	FOR_EACH_HOSTPING(hp) {
+		if (strcmp(hp->name, name) == 0) {
+			hostping_delete(hp);
+			rc = 0;
+			break;
+		}
+	}
+	pthread_rwlock_unlock(&hostping_rwlock);
+	return rc;
+}
+
+int
+hostping_add_name(char const *name)
+{
+	int rc = 0;
+	struct addrinfo hints, *res;
+	HOSTPING *hp;
+	
+	pthread_rwlock_rdlock(&hostping_rwlock);
+	FOR_EACH_HOSTPING(hp) {
+		if (strcmp(hp->name, name) == 0) {
+			rc = -1;
+			break;
+		}
+	}
+	pthread_rwlock_unlock(&hostping_rwlock);
+	if (rc)
+		return rc;
+
+	memset(&hints, 0, sizeof(hints));
+	hints.ai_family = AF_INET;
+	hints.ai_protocol = IPPROTO_TCP;
+	rc = getaddrinfo(name, NULL, &hints, &res);
+	if (rc) {
+		return -2;
+	}
+	
+	pthread_rwlock_wrlock(&hostping_rwlock);
+	hostping_add(name, res->ai_addr, res->ai_addrlen);
+	pthread_rwlock_unlock(&hostping_rwlock);
+	freeaddrinfo(res);
+	return 0;
+}
 
 static int ping_fd;
 
@@ -493,8 +613,7 @@ p903_init(void)
 	int i;
 	
 	if (hostping_count == 0) {
-		fatal("no host IPs configured, nothing to do?");
-		exit(1);
+		info("no IP addresses configured, starting anyway");
 	}
 
 	proto = getprotobyname("icmp");
@@ -683,6 +802,7 @@ p903_sender(void *p)
 			send_count = 0;
 		}
 		clock_gettime(CLOCK_MONOTONIC, &ts);
+		pthread_rwlock_rdlock(&hostping_rwlock);
 		FOR_EACH_HOSTPING(hp) {
 			struct timespec nts;
 			clock_gettime(CLOCK_MONOTONIC, &nts);
@@ -699,6 +819,7 @@ p903_sender(void *p)
 						TIMER_ABSTIME, &nts,
 						NULL);
 		}
+		pthread_rwlock_unlock(&hostping_rwlock);
 		send_count++;
 		if (send_count == ping_count)
 			send_p = 0;
@@ -827,11 +948,14 @@ p903_scheduler(void *p)
 {
 	while (1) {
 		HOSTPING *hp;
-
+		
+		pthread_rwlock_rdlock(&hostping_rwlock);
 		/* Reset all statistics */
 		FOR_EACH_HOSTPING(hp) {
 			hostping_reset(hp);
 		}
+		pthread_rwlock_unlock(&hostping_rwlock);
+
 		start_probe();
 		sleep(probe_interval);
 		if (verbose)