support removing of http callbacks and removing of registered RPCs

svn:r355

buffer.c

@@ -44,6 +44,7 @@
 #include <sys/ioctl.h>
 #endif
 
+#include <assert.h>
 #include <errno.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -134,9 +135,13 @@ evbuffer_add_vprintf(struct evbuffer *buf, const char *fmt, va_list ap)
 	int sz;
 	va_list aq;
 
+	/* make sure that at least some space is available */
+	evbuffer_expand(buf, 64);
 	for (;;) {
+		size_t used = buf->misalign + buf->off;
 		buffer = (char *)buf->buffer + buf->off;
-		space = buf->totallen - buf->misalign - buf->off;
+		assert(buf->totallen >= used);
+		space = buf->totallen - used;
 
 #ifndef va_copy
 #define	va_copy(dst, src)	memcpy(&(dst), &(src), sizeof(va_list))
@@ -152,7 +157,7 @@ evbuffer_add_vprintf(struct evbuffer *buf, const char *fmt, va_list ap)
 
 		va_end(aq);
 
-		if (sz == -1)
+		if (sz < 0)
 			return (-1);
 		if (sz < space) {
 			buf->off += sz;

evhttp.h

@@ -75,6 +75,9 @@ void evhttp_free(struct evhttp* http);
 void evhttp_set_cb(struct evhttp *, const char *,
     void (*)(struct evhttp_request *, void *), void *);
 
+/* Removes the callback for a specified URI */
+int evhttp_del_cb(struct evhttp *, const char *);
+
 /* Set a callback for all requests that are not caught by specific callbacks */
 void evhttp_set_gencb(struct evhttp *,
     void (*)(struct evhttp_request *, void *), void *);

evrpc.c

@@ -133,6 +133,35 @@ evrpc_register_rpc(struct evrpc_base *base, struct evrpc *rpc,
 	return (0);
 }
 
+int
+evrpc_unregister_rpc(struct evrpc_base *base, const char *name)
+{
+	char *registered_uri = NULL;
+	struct evrpc *rpc;
+
+	/* find the right rpc; linear search might be slow */
+	TAILQ_FOREACH(rpc, &base->registered_rpcs, next) {
+		if (strcmp(rpc->uri, name) == 0)
+			break;
+	}
+	if (rpc == NULL) {
+		/* We did not find an RPC with this name */
+		return (-1);
+	}
+	TAILQ_REMOVE(&base->registered_rpcs, rpc, next);
+	
+	free((char *)rpc->uri);
+	free(rpc);
+
+        registered_uri = evrpc_construct_uri(name);
+
+	/* remove the http server callback */
+	assert(evhttp_del_cb(base->http_server, registered_uri) == 0);
+
+	free(registered_uri);
+	return (0);
+}
+
 static void
 evrpc_request_cb(struct evhttp_request *req, void *arg)
 {

evrpc.h

@@ -223,6 +223,11 @@ struct evrpc_base *evrpc_init(struct evhttp *server);
 int evrpc_register_rpc(struct evrpc_base *, struct evrpc *,
     void (*)(struct evrpc_req_generic*, void *), void *);
 
+/* Takes the named RPCs and tried to unregister it */
+#define EVRPC_UNREGISTER(base, name) evrpc_unregister_rpc(base, #name)
+
+int evrpc_unregister_rpc(struct evrpc_base *, const char *name);
+
 /*
  * Client-side RPC support
  */

http.c

@@ -1976,6 +1976,25 @@ evhttp_set_cb(struct evhttp *http, const char *uri,
 	TAILQ_INSERT_TAIL(&http->callbacks, http_cb, next);
 }
 
+int
+evhttp_del_cb(struct evhttp *http, const char *uri)
+{
+	struct evhttp_cb *http_cb;
+
+	TAILQ_FOREACH(http_cb, &http->callbacks, next) {
+		if (strcmp(http_cb->what, uri) == 0)
+			break;
+	}
+	if (http_cb == NULL)
+		return (-1);
+
+	TAILQ_REMOVE(&http->callbacks, http_cb, next);
+	free(http_cb->what);
+	free(http_cb);
+
+	return (0);
+}
+
 void
 evhttp_set_gencb(struct evhttp *http,
     void (*cb)(struct evhttp_request *, void *), void *cbarg)

test/regress_rpc.c

@@ -128,6 +128,13 @@ rpc_setup(struct evhttp **phttp, short *pport, struct evrpc_base **pbase)
 	*pbase = base;
 }
 
+static void
+rpc_teardown(struct evrpc_base *base)
+{
+	assert(EVRPC_UNREGISTER(base, Message) == 0);
+	assert(EVRPC_UNREGISTER(base, NeverReply) == 0);
+}
+
 static void
 rpc_postrequest_failure(struct evhttp_request *req, void *arg)
 {
@@ -190,6 +197,8 @@ rpc_basic_test(void)
 
 	event_dispatch();
 
+	rpc_teardown(base);
+	
 	if (test_ok != 1) {
 		fprintf(stdout, "FAILED\n");
 		exit(1);
@@ -276,6 +285,8 @@ rpc_basic_message(void)
 
 	event_dispatch();
 	
+	rpc_teardown(base);
+	
 	if (test_ok != 1) {
 		fprintf(stdout, "FAILED\n");
 		exit(1);
@@ -399,6 +410,8 @@ rpc_basic_client(void)
 
 	event_dispatch();
 	
+	rpc_teardown(base);
+	
 	if (test_ok != 2) {
 		fprintf(stdout, "FAILED (2)\n");
 		exit(1);
@@ -448,6 +461,8 @@ rpc_basic_queued_client(void)
 
 	event_dispatch();
 	
+	rpc_teardown(base);
+	
 	if (test_ok != 2) {
 		fprintf(stdout, "FAILED (1)\n");
 		exit(1);
@@ -508,6 +523,8 @@ rpc_client_timeout(void)
 
 	event_dispatch();
 	
+	rpc_teardown(base);
+	
 	if (test_ok != 2) {
 		fprintf(stdout, "FAILED (1)\n");
 		exit(1);