#include <sys/socket.h>
#include <sys/un.h>
#include <unistd.h>
+#include <poll.h>
#include <stdio.h>
#include <stdlib.h>
#define MSG_MAX 1000
+/* 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];
// backtrace_symbols_fd(buffer, result, STDERR_FILENO);
//}
+char *strdup_malloc(const char *s)
+{
+ char *retval;
+
+ if(s == NULL)
+ return NULL;
+
+ retval = (char *) malloc(strlen(s)+1);
+
+ strcpy(retval, s);
+
+ return retval;
+}
+
static void signal_process(pid_t pid)
{
int result;
sleep(1);
}
+int send_message_fd(int fd, const char *msg, char **reply)
+{
+ int result;
+
+ result = send(fd, msg, strlen(msg), 0);
+ if(result == -1) {
+ PERROR("send");
+ return -1;
+ }
+ else if(result == 0) {
+ return 0;
+ }
+
+ if(!reply)
+ 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)
{
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;
if(signalpid >= 0)
signal_process(signalpid);
- result = sendto(fd, msg, strlen(msg), 0, (struct sockaddr *)&addr, sizeof(addr));
+ result = connect(fd, (struct sockaddr *)&addr, sizeof(addr));
if(result == -1) {
- PERROR("sendto");
+ PERROR("connect");
return -1;
}
- if(!reply)
- return 0;
-
- *reply = (char *) malloc(MSG_MAX+1);
- result = recvfrom(fd, *reply, MSG_MAX, 0, NULL, NULL);
- if(result == -1) {
- PERROR("recvfrom");
- return -1;
- }
-
- (*reply)[result] = '\0';
-
- return 0;
+ return send_message_fd(fd, msg, reply);
}
/* pid: the pid of the trace process that must receive the msg
return 0;
}
+/* 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;
- size_t initial_addrlen,addrlen;
*msg = (char *) malloc(MSG_MAX+1);
- if(src) {
- initial_addrlen = addrlen = sizeof(src->addr);
-
- result = recvfrom(fd, *msg, MSG_MAX, 0, &src->addr, &addrlen);
- if(initial_addrlen != addrlen) {
- ERR("recvfrom: unexpected address length");
- return -1;
- }
- }
- else {
- 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;
}
DBG("ustcomm_app_recv_message: result is %d, message is %s", result, (*msg));
+ 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, NULL);
+ if(result) {
+ 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, struct ustcomm_source *src)
+int ustcomm_ustd_recv_message(struct ustcomm_ustd *ustd, char **msg, struct ustcomm_source *src, int timeout)
{
- return recv_message_fd(ustd->fd, msg, src);
+ return ustcomm_recv_message(&ustd->server, msg, src, timeout);
}
-int ustcomm_app_recv_message(struct ustcomm_app *app, char **msg, struct ustcomm_source *src)
+int ustcomm_app_recv_message(struct ustcomm_app *app, char **msg, struct ustcomm_source *src, int timeout)
{
- return recv_message_fd(app->fd, msg, src);
+ 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)
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;
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);
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:
return -1;
}
- handle->fd = init_named_socket(name, &handle->socketpath);
- if(handle->fd < 0)
- return handle->fd;
+ 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:
+ free(name);
+ return -1;
}
-char *find_tok(const char *str)
+static char *find_tok(char *str)
{
while(*str == ' ') {
str++;
retval = NULL;
}
- retval = strndupa(start, end-start);
+ asprintf(&retval, "%.*s", (int)(end-start), start);
return retval;
}