X-Git-Url: http://git.lttng.org/?a=blobdiff_plain;f=libustcomm%2Fustcomm.c;h=3b53471ac6d69c81acd1379351d985b9b8ed177b;hb=803a4f584bbc64ff44173ced627636f9e6db6618;hp=6047b6012bc5f5abb98c45c2e28a4038b6b438a6;hpb=688760ef257bee85e3841e0d27ecf4e2f921ef00;p=ust.git diff --git a/libustcomm/ustcomm.c b/libustcomm/ustcomm.c index 6047b60..3b53471 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 #include @@ -6,6 +23,7 @@ #include #include #include +#include #include #include @@ -16,8 +34,6 @@ #include "localerr.h" #define UNIX_PATH_MAX 108 -#define SOCK_DIR "/tmp/socks" -#define UST_SIGNAL SIGIO #define MSG_MAX 1000 @@ -49,20 +65,27 @@ char *strdup_malloc(const char *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; } - sleep(1); + /* FIXME: should wait in a better way */ + //sleep(1); + + return 0; +} + +int pid_is_online(pid_t pid) { + return kill(pid, UST_SIGNAL) != -1; } -int send_message_fd(int fd, const char *msg, char **reply) +static int send_message_fd(int fd, const char *msg) { int result; @@ -75,98 +98,58 @@ int send_message_fd(int fd, const char *msg, char **reply) 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) +/* Called by an app to ask the consumer daemon to connect to it. */ + +int ustcomm_request_consumer(pid_t pid, const char *channel) { - int fd; + char path[UNIX_PATH_MAX]; int result; - struct sockaddr_un addr; - - result = fd = socket(PF_UNIX, SOCK_STREAM, 0); - if(result == -1) { - PERROR("socket"); - return -1; + char *msg=NULL; + int retval = 0; + struct ustcomm_connection conn; + char *explicit_daemon_socket_path; + + explicit_daemon_socket_path = getenv("UST_DAEMON_SOCKET"); + if(explicit_daemon_socket_path) { + /* user specified explicitly a socket path */ + result = snprintf(path, UNIX_PATH_MAX, "%s", explicit_daemon_socket_path); + } + else { + /* just use the default path */ + result = snprintf(path, UNIX_PATH_MAX, "%s/ustd", SOCK_DIR); } - 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) - signal_process(signalpid); + asprintf(&msg, "collect %d %s", pid, channel); - result = connect(fd, (struct sockaddr *)&addr, sizeof(addr)); + /* don't signal it because it's the daemon */ + result = ustcomm_connect_path(path, &conn, -1); if(result == -1) { - PERROR("connect"); - return -1; - } - - return send_message_fd(fd, msg, reply); -} - -/* 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; + WARN("ustcomm_connect_path failed"); + retval = -1; + goto del_string; } - send_message_path(path, msg, reply, pid); - - return 0; -} - -/* Called by an app to ask the consumer daemon to connect to it. */ - -int ustcomm_request_consumer(pid_t pid, const char *channel) -{ - char path[UNIX_PATH_MAX]; - int result; - char *msg; - - result = snprintf(path, UNIX_PATH_MAX, "%s/ustd", SOCK_DIR); - if(result >= UNIX_PATH_MAX) { - fprintf(stderr, "string overflow allocating socket name"); - return -1; + result = ustcomm_send_request(&conn, msg, NULL); + if(result == -1) { + WARN("ustcomm_send_request failed"); + retval = -1; + goto disconnect; } - asprintf(&msg, "collect %d %s", pid, channel); - - send_message_path(path, msg, NULL, -1); + disconnect: + ustcomm_disconnect(&conn); + del_string: free(msg); - return 0; + return retval; } /* returns 1 to indicate a message was received @@ -200,8 +183,8 @@ int ustcomm_send_reply(struct ustcomm_server *server, char *msg, struct ustcomm_ { int result; - result = send_message_fd(src->fd, msg, NULL); - if(result) { + result = send_message_fd(src->fd, msg); + if(result < 0) { ERR("error in send_message_fd"); return -1; } @@ -209,6 +192,23 @@ int ustcomm_send_reply(struct ustcomm_server *server, char *msg, struct ustcomm_ return 0; } +/* Called after a fork. */ + +int ustcomm_close_all_connections(struct ustcomm_server *server) +{ + struct ustcomm_connection *conn; + struct ustcomm_connection *deletable_conn = NULL; + + list_for_each_entry(conn, &server->connections, list) { + free(deletable_conn); + deletable_conn = conn; + close(conn->fd); + list_del(&conn->list); + } + + return 0; +} + /* @timeout: max blocking time in milliseconds, -1 means infinity * * returns 1 to indicate a message was received @@ -248,7 +248,8 @@ int ustcomm_recv_message(struct ustcomm_server *server, char **msg, struct ustco idx++; } - result = poll(fds, n_fds, timeout); + while((result = poll(fds, n_fds, timeout)) == -1 && errno == EINTR) + /* nothing */; if(result == -1) { PERROR("poll"); return -1; @@ -316,7 +317,27 @@ int ustcomm_app_recv_message(struct ustcomm_app *app, char **msg, struct ustcomm return ustcomm_recv_message(&app->server, msg, src, timeout); } -static int init_named_socket(char *name, char **path_out) +/* 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(const char *name, char **path_out) { int result; int fd; @@ -358,8 +379,7 @@ static int init_named_socket(char *name, char **path_out) } if(path_out) { - *path_out = ""; - *path_out = strdupa(addr.sun_path); + *path_out = strdup(addr.sun_path); } return fd; @@ -370,6 +390,97 @@ static int init_named_socket(char *name, char **path_out) return -1; } +int ustcomm_send_request(struct ustcomm_connection *conn, const 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(const 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) { + ERR("string overflow allocating socket name"); + return -1; + } + + return ustcomm_connect_path(path, conn, pid); +} + +/* Called by an application to initialize its server so daemons can + * connect to it. + */ + int ustcomm_init_app(pid_t pid, struct ustcomm_app *handle) { int result; @@ -397,31 +508,61 @@ free_name: return -1; } -int ustcomm_init_ustd(struct ustcomm_ustd *handle) +/* Used by the daemon to initialize its server so applications + * can connect to it. + */ + +int ustcomm_init_ustd(struct ustcomm_ustd *handle, const char *sock_path) { - int result; char *name; + int retval = 0; - result = asprintf(&name, "%s/%s", SOCK_DIR, "ustd"); - if(result >= UNIX_PATH_MAX) { - ERR("string overflow allocating socket name"); - return -1; + if(sock_path) { + asprintf(&name, "%s", sock_path); + } + else { + asprintf(&name, "%s/%s", SOCK_DIR, "ustd"); } handle->server.listen_fd = init_named_socket(name, &handle->server.socketpath); if(handle->server.listen_fd < 0) { - ERR("error initializing named socket"); + ERR("error initializing named socket at %s", name); + retval = -1; goto free_name; } - free(name); INIT_LIST_HEAD(&handle->server.connections); - return 0; - free_name: free(name); - return -1; + + return retval; +} + +void ustcomm_fini_app(struct ustcomm_app *handle) +{ + int result; + struct stat st; + + /* Destroy socket */ + ERR("socket path is: %s", handle->server.socketpath); + result = stat(handle->server.socketpath, &st); + if(result == -1) { + PERROR("stat (%s)", handle->server.socketpath); + return; + } + + /* Paranoid check before deleting. */ + result = S_ISSOCK(st.st_mode); + if(!result) { + ERR("The socket we are about to delete is not a socket."); + return; + } + + result = unlink(handle->server.socketpath); + if(result == -1) { + PERROR("unlink"); + } } static char *find_tok(char *str)