X-Git-Url: http://git.lttng.org/?a=blobdiff_plain;f=libustcomm%2Fustcomm.c;h=225d1990be042a18cf0cde7c297e92c61b48c386;hb=c39c72ee5890c7727ae2697f321ba1b3d6c862f5;hp=0275a736b99a22b7f4b82304f5c289ca2544446d;hpb=b0540e11c3e9a3596b4b3865b0960d693fa66a88;p=ust.git

diff --git a/libustcomm/ustcomm.c b/libustcomm/ustcomm.c
index 0275a73..225d199 100644
--- a/libustcomm/ustcomm.c
+++ b/libustcomm/ustcomm.c
@@ -1,3 +1,20 @@
+/* Copyright (C) 2009  Pierre-Marc Fournier
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301 USA
+ */
+
 #define _GNU_SOURCE
 #include <sys/types.h>
 #include <signal.h>
@@ -5,6 +22,7 @@
 #include <sys/socket.h>
 #include <sys/un.h>
 #include <unistd.h>
+#include <poll.h>
 
 #include <stdio.h>
 #include <stdlib.h>
@@ -20,35 +38,87 @@
 
 #define MSG_MAX 1000
 
-static void bt(void)
+/* FIXME: ustcomm blocks on message sending, which might be problematic in
+ * some cases. Fix the poll() usage so sends are buffered until they don't
+ * block.
+ */
+
+//static void bt(void)
+//{
+//	void *buffer[100];
+//	int result;
+//
+//	result = backtrace(&buffer, 100);
+//	backtrace_symbols_fd(buffer, result, STDERR_FILENO);
+//}
+
+char *strdup_malloc(const char *s)
 {
-	void *buffer[100];
-	int result;
+	char *retval;
+
+	if(s == NULL)
+		return NULL;
 
-	result = backtrace(&buffer, 100);
-	backtrace_symbols_fd(buffer, result, STDERR_FILENO);
+	retval = (char *) malloc(strlen(s)+1);
+
+	strcpy(retval, s);
+
+	return retval;
 }
 
-static void signal_process(pid_t pid)
+static int signal_process(pid_t pid)
 {
 	int result;
 
 	result = kill(pid, UST_SIGNAL);
 	if(result == -1) {
 		PERROR("kill");
-		return;
+		return -1;
+	}
+
+	/* FIXME: should wait in a better way */
+	//sleep(1);
+
+	return 0;
+}
+
+static int send_message_fd(int fd, const char *msg)
+{
+	int result;
+
+	result = send(fd, msg, strlen(msg), 0);
+	if(result == -1) {
+		PERROR("send");
+		return -1;
+	}
+	else if(result == 0) {
+		return 0;
 	}
 
-	sleep(1);
+	return 1;
+
+//	*reply = (char *) malloc(MSG_MAX+1);
+//	result = recv(fd, *reply, MSG_MAX, 0);
+//	if(result == -1) {
+//		PERROR("recv");
+//		return -1;
+//	}
+//	else if(result == 0) {
+//		return 0;
+//	}
+//	
+//	(*reply)[result] = '\0';
+//
+//	return 1;
 }
 
-int send_message_path(const char *path, const char *msg, char **reply, int signalpid)
+static int send_message_path(const char *path, const char *msg, int signalpid)
 {
 	int fd;
 	int result;
 	struct sockaddr_un addr;
 
-	result = fd = socket(PF_UNIX, SOCK_DGRAM, 0);
+	result = fd = socket(PF_UNIX, SOCK_STREAM, 0);
 	if(result == -1) {
 		PERROR("socket");
 		return -1;
@@ -62,51 +132,44 @@ int send_message_path(const char *path, const char *msg, char **reply, int signa
 		return -1;
 	}
 
-	if(signalpid >= 0)
-		signal_process(signalpid);
-
-	result = sendto(fd, msg, strlen(msg), 0, (struct sockaddr *)&addr, sizeof(addr));
-	if(result == -1) {
-		PERROR("sendto");
-		return -1;
+	if(signalpid >= 0) {
+		result = signal_process(signalpid);
+		if(result == -1) {
+			ERR("could not signal process");
+			return -1;
+		}
 	}
 
-	if(!reply)
-		return 0;
-
-	*reply = (char *) malloc(MSG_MAX+1);
-	result = recvfrom(fd, *reply, MSG_MAX, 0, NULL, NULL);
+	result = connect(fd, (struct sockaddr *)&addr, sizeof(addr));
 	if(result == -1) {
-		PERROR("recvfrom");
+		PERROR("connect");
 		return -1;
 	}
-	
-	(*reply)[result] = '\0';
 
-	return 0;
+	return send_message_fd(fd, msg);
 }
 
-/* pid: the pid of the trace process that must receive the msg
-   msg: pointer to a null-terminated message to send
-   reply: location where to put the null-terminated string of the reply;
-	  it must be free'd after usage
- */
-
-int send_message(pid_t pid, const char *msg, char **reply)
-{
-	int result;
-	char path[UNIX_PATH_MAX];
-
-	result = snprintf(path, UNIX_PATH_MAX, "%s/%d", SOCK_DIR, pid);
-	if(result >= UNIX_PATH_MAX) {
-		fprintf(stderr, "string overflow allocating socket name");
-		return -1;
-	}
-
-	send_message_path(path, msg, reply, pid);
-
-	return 0;
-}
+///* pid: the pid of the trace process that must receive the msg
+//   msg: pointer to a null-terminated message to send
+//   reply: location where to put the null-terminated string of the reply;
+//	  it must be free'd after usage
+// */
+//
+//int send_message_pid(pid_t pid, const char *msg, char **reply)
+//{
+//	int result;
+//	char path[UNIX_PATH_MAX];
+//
+//	result = snprintf(path, UNIX_PATH_MAX, "%s/%d", SOCK_DIR, pid);
+//	if(result >= UNIX_PATH_MAX) {
+//		fprintf(stderr, "string overflow allocating socket name");
+//		return -1;
+//	}
+//
+//	send_message_path(path, msg, reply, pid);
+//
+//	return 0;
+//}
 
 /* Called by an app to ask the consumer daemon to connect to it. */
 
@@ -124,21 +187,26 @@ int ustcomm_request_consumer(pid_t pid, const char *channel)
 
 	asprintf(&msg, "collect %d %s", pid, channel); 
 
-	send_message_path(path, msg, NULL, pid);
+	send_message_path(path, msg, -1);
 	free(msg);
 
 	return 0;
 }
 
-static int recv_message_fd(int fd, char **msg)
+/* returns 1 to indicate a message was received
+ * returns 0 to indicate no message was received (cannot happen)
+ * returns -1 to indicate an error
+ */
+
+static int recv_message_fd(int fd, char **msg, struct ustcomm_source *src)
 {
 	int result;
-	struct sockaddr_un addr;
 
 	*msg = (char *) malloc(MSG_MAX+1);
-	result = recvfrom(fd, *msg, MSG_MAX, 0, NULL, NULL);
+
+	result = recv(fd, *msg, MSG_MAX, 0);
 	if(result == -1) {
-		PERROR("recvfrom");
+		PERROR("recv");
 		return -1;
 	}
 
@@ -146,19 +214,150 @@ static int recv_message_fd(int fd, char **msg)
 	
 	DBG("ustcomm_app_recv_message: result is %d, message is %s", result, (*msg));
 
-	bt();
+	if(src)
+		src->fd = fd;
+
+	return 1;
+}
+
+int ustcomm_send_reply(struct ustcomm_server *server, char *msg, struct ustcomm_source *src)
+{
+	int result;
+
+	result = send_message_fd(src->fd, msg);
+	if(result < 0) {
+		ERR("error in send_message_fd");
+		return -1;
+	}
 
 	return 0;
+} 
+
+/* @timeout: max blocking time in milliseconds, -1 means infinity
+ *
+ * returns 1 to indicate a message was received
+ * returns 0 to indicate no message was received
+ * returns -1 to indicate an error
+ */
+
+int ustcomm_recv_message(struct ustcomm_server *server, char **msg, struct ustcomm_source *src, int timeout)
+{
+	struct pollfd *fds;
+	struct ustcomm_connection *conn;
+	int result;
+	int retval;
+
+	for(;;) {
+		int idx = 0;
+		int n_fds = 1;
+
+		list_for_each_entry(conn, &server->connections, list) {
+			n_fds++;
+		}
+
+		fds = (struct pollfd *) malloc(n_fds * sizeof(struct pollfd));
+		if(fds == NULL) {
+			ERR("malloc returned NULL");
+			return -1;
+		}
+
+		/* special idx 0 is for listening socket */
+		fds[idx].fd = server->listen_fd;
+		fds[idx].events = POLLIN;
+		idx++;
+
+		list_for_each_entry(conn, &server->connections, list) {
+			fds[idx].fd = conn->fd;
+			fds[idx].events = POLLIN;
+			idx++;
+		}
+
+		result = poll(fds, n_fds, timeout);
+		if(result == -1) {
+			PERROR("poll");
+			return -1;
+		}
+
+		if(result == 0)
+			return 0;
+
+		if(fds[0].revents) {
+			struct ustcomm_connection *newconn;
+			int newfd;
+
+			result = newfd = accept(server->listen_fd, NULL, NULL);
+			if(result == -1) {
+				PERROR("accept");
+				return -1;
+			}
+
+			newconn = (struct ustcomm_connection *) malloc(sizeof(struct ustcomm_connection));
+			if(newconn == NULL) {
+				ERR("malloc returned NULL");
+				return -1;
+			}
+
+			newconn->fd = newfd;
+
+			list_add(&newconn->list, &server->connections);
+		}
+
+		for(idx=1; idx<n_fds; idx++) {
+			if(fds[idx].revents) {
+				retval = recv_message_fd(fds[idx].fd, msg, src);
+				if(**msg == 0) {
+					/* connection finished */
+					close(fds[idx].fd);
+
+					list_for_each_entry(conn, &server->connections, list) {
+						if(conn->fd == fds[idx].fd) {
+							list_del(&conn->list);
+							break;
+						}
+					}
+				}
+				else {
+					goto free_fds_return;
+				}
+			}
+		}
+
+		free(fds);
+	}
+
+free_fds_return:
+	free(fds);
+	return retval;
 }
 
-int ustcomm_ustd_recv_message(struct ustcomm_ustd *ustd, char **msg)
+int ustcomm_ustd_recv_message(struct ustcomm_ustd *ustd, char **msg, struct ustcomm_source *src, int timeout)
 {
-	return recv_message_fd(ustd->fd, msg);
+	return ustcomm_recv_message(&ustd->server, msg, src, timeout);
 }
 
-int ustcomm_app_recv_message(struct ustcomm_app *app, char **msg)
+int ustcomm_app_recv_message(struct ustcomm_app *app, char **msg, struct ustcomm_source *src, int timeout)
 {
-	return recv_message_fd(app->fd, msg);
+	return ustcomm_recv_message(&app->server, msg, src, timeout);
+}
+
+/* This removes src from the list of active connections of app.
+ */
+
+int ustcomm_app_detach_client(struct ustcomm_app *app, struct ustcomm_source *src)
+{
+	struct ustcomm_server *server = (struct ustcomm_server *)app;
+	struct ustcomm_connection *conn;
+
+	list_for_each_entry(conn, &server->connections, list) {
+		if(conn->fd == src->fd) {
+			list_del(&conn->list);
+			goto found;
+		}
+	}
+
+	return -1;
+found:
+	return src->fd;
 }
 
 static int init_named_socket(char *name, char **path_out)
@@ -168,7 +367,7 @@ static int init_named_socket(char *name, char **path_out)
 
 	struct sockaddr_un addr;
 	
-	result = fd = socket(PF_UNIX, SOCK_DGRAM, 0);
+	result = fd = socket(PF_UNIX, SOCK_STREAM, 0);
 	if(result == -1) {
 		PERROR("socket");
 		return -1;
@@ -179,12 +378,29 @@ static int init_named_socket(char *name, char **path_out)
 	strncpy(addr.sun_path, name, UNIX_PATH_MAX);
 	addr.sun_path[UNIX_PATH_MAX-1] = '\0';
 
+	result = access(name, F_OK);
+	if(result == 0) {
+		/* file exists */
+		result = unlink(name);
+		if(result == -1) {
+			PERROR("unlink of socket file");
+			goto close_sock;
+		}
+		WARN("socket already exists; overwriting");
+	}
+
 	result = bind(fd, (struct sockaddr *)&addr, sizeof(addr));
 	if(result == -1) {
 		PERROR("bind");
 		goto close_sock;
 	}
 
+	result = listen(fd, 1);
+	if(result == -1) {
+		PERROR("listen");
+		goto close_sock;
+	}
+
 	if(path_out) {
 		*path_out = "";
 		*path_out = strdupa(addr.sun_path);
@@ -198,6 +414,99 @@ static int init_named_socket(char *name, char **path_out)
 	return -1;
 }
 
+int ustcomm_send_request(struct ustcomm_connection *conn, char *req, char **reply)
+{
+	int result;
+
+	result = send(conn->fd, req, strlen(req), 0);
+	if(result == -1) {
+		PERROR("send");
+		return -1;
+	}
+
+	if(!reply)
+		return 1;
+
+	*reply = (char *) malloc(MSG_MAX+1);
+	result = recv(conn->fd, *reply, MSG_MAX, 0);
+	if(result == -1) {
+		PERROR("recv");
+		return -1;
+	}
+	else if(result == 0) {
+		return 0;
+	}
+	
+	(*reply)[result] = '\0';
+
+	return 1;
+}
+
+int ustcomm_connect_path(char *path, struct ustcomm_connection *conn, pid_t signalpid)
+{
+	int fd;
+	int result;
+	struct sockaddr_un addr;
+
+	result = fd = socket(PF_UNIX, SOCK_STREAM, 0);
+	if(result == -1) {
+		PERROR("socket");
+		return -1;
+	}
+
+	addr.sun_family = AF_UNIX;
+
+	result = snprintf(addr.sun_path, UNIX_PATH_MAX, "%s", path);
+	if(result >= UNIX_PATH_MAX) {
+		ERR("string overflow allocating socket name");
+		return -1;
+	}
+
+	if(signalpid >= 0) {
+		result = signal_process(signalpid);
+		if(result == -1) {
+			ERR("could not signal process");
+			return -1;
+		}
+	}
+
+	result = connect(fd, (struct sockaddr *)&addr, sizeof(addr));
+	if(result == -1) {
+		PERROR("connect");
+		return -1;
+	}
+
+	conn->fd = fd;
+
+	return 0;
+}
+
+int ustcomm_disconnect(struct ustcomm_connection *conn)
+{
+	return close(conn->fd);
+}
+
+int ustcomm_connect_app(pid_t pid, struct ustcomm_connection *conn)
+{
+	int result;
+	char path[UNIX_PATH_MAX];
+
+
+	result = snprintf(path, UNIX_PATH_MAX, "%s/%d", SOCK_DIR, pid);
+	if(result >= UNIX_PATH_MAX) {
+		fprintf(stderr, "string overflow allocating socket name");
+		return -1;
+	}
+
+	return ustcomm_connect_path(path, conn, pid);
+}
+
+int ustcomm_disconnect_app(struct ustcomm_connection *conn)
+{
+	close(conn->fd);
+	return 0;
+}
+
 int ustcomm_init_app(pid_t pid, struct ustcomm_app *handle)
 {
 	int result;
@@ -209,12 +518,15 @@ int ustcomm_init_app(pid_t pid, struct ustcomm_app *handle)
 		return -1;
 	}
 
-	handle->fd = init_named_socket(name, &(handle->socketpath));
-	if(handle->fd < 0) {
+	handle->server.listen_fd = init_named_socket(name, &(handle->server.socketpath));
+	if(handle->server.listen_fd < 0) {
+		ERR("error initializing named socket");
 		goto free_name;
 	}
 	free(name);
 
+	INIT_LIST_HEAD(&handle->server.connections);
+
 	return 0;
 
 free_name:
@@ -224,9 +536,112 @@ free_name:
 
 int ustcomm_init_ustd(struct ustcomm_ustd *handle)
 {
-	handle->fd = init_named_socket("ustd", &handle->socketpath);
-	if(handle->fd < 0)
-		return handle->fd;
+	int result;
+	char *name;
+
+	result = asprintf(&name, "%s/%s", SOCK_DIR, "ustd");
+	if(result >= UNIX_PATH_MAX) {
+		ERR("string overflow allocating socket name");
+		return -1;
+	}
+
+	handle->server.listen_fd = init_named_socket(name, &handle->server.socketpath);
+	if(handle->server.listen_fd < 0) {
+		ERR("error initializing named socket at %s", name);
+		goto free_name;
+	}
+	free(name);
+
+	INIT_LIST_HEAD(&handle->server.connections);
 
 	return 0;
+
+free_name:
+	free(name);
+	return -1;
 }
+
+static char *find_tok(char *str)
+{
+	while(*str == ' ') {
+		str++;
+
+		if(*str == 0)
+			return NULL;
+	}
+
+	return str;
+}
+
+static char *find_sep(char *str)
+{
+	while(*str != ' ') {
+		str++;
+
+		if(*str == 0)
+			break;
+	}
+
+	return str;
+}
+
+int nth_token_is(char *str, char *token, int tok_no)
+{
+	int i;
+	char *start;
+	char *end;
+
+	for(i=0; i<=tok_no; i++) {
+		str = find_tok(str);
+		if(str == NULL)
+			return -1;
+
+		start = str;
+
+		str = find_sep(str);
+		if(str == NULL)
+			return -1;
+
+		end = str;
+	}
+
+	if(end-start != strlen(token))
+		return 0;
+
+	if(strncmp(start, token, end-start))
+		return 0;
+
+	return 1;
+}
+
+char *nth_token(char *str, int tok_no)
+{
+	static char *retval = NULL;
+	int i;
+	char *start;
+	char *end;
+
+	for(i=0; i<=tok_no; i++) {
+		str = find_tok(str);
+		if(str == NULL)
+			return NULL;
+
+		start = str;
+
+		str = find_sep(str);
+		if(str == NULL)
+			return NULL;
+
+		end = str;
+	}
+
+	if(retval) {
+		free(retval);
+		retval = NULL;
+	}
+
+	asprintf(&retval, "%.*s", (int)(end-start), start);
+
+	return retval;
+}
+