+/* 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
+ */
+
+/* API used by UST components to communicate with each other via sockets. */
+
#define _GNU_SOURCE
#include <sys/types.h>
#include <signal.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <unistd.h>
+#include <poll.h>
+#include <sys/epoll.h>
+#include <sys/stat.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
+#include <execinfo.h>
#include "ustcomm.h"
-#include "localerr.h"
+#include "usterr.h"
+#include "share.h"
-#define UNIX_PATH_MAX 108
-#define SOCK_DIR "/tmp/socks"
-#define UST_SIGNAL SIGIO
+static int mkdir_p(const char *path, mode_t mode)
+{
+ const char *path_p;
+ char *tmp;
-#define MSG_MAX 1000
+ int retval = 0;
+ int result;
+ mode_t old_umask;
+
+ tmp = zmalloc(strlen(path) + 1);
+ if (tmp == NULL)
+ return -1;
-static void signal_process(pid_t pid)
+ /* skip first / */
+ path_p = path+1;
+
+ old_umask = umask(0);
+ for(;;) {
+ while (*path_p != '/') {
+ if(*path_p == 0)
+ break;
+ ++path_p;
+ }
+ if (*path_p == '/') {
+ strncpy(tmp, path, path_p - path);
+ tmp[path_p-path] = '\0';
+ if (tmp[path_p - path - 1] != '/') {
+ result = mkdir(tmp, mode);
+ if(result == -1) {
+ if (!(errno == EEXIST || errno == EACCES || errno == EROFS)) {
+ /* Then this is a real error */
+ retval = -1;
+ break;
+ }
+ }
+ }
+ /* pass / */
+ path_p++;
+ } else {
+ /* last component */
+ result = mkdir(path, mode);
+ if (result == -1)
+ retval = -1;
+ break;
+ }
+ }
+
+ free(tmp);
+ umask(old_umask);
+ return retval;
+}
+
+static struct sockaddr_un * create_sock_addr(const char *name,
+ size_t *sock_addr_size)
{
- int result;
+ struct sockaddr_un * addr;
+ size_t alloc_size;
- result = kill(pid, UST_SIGNAL);
- if(result == -1) {
- perror("kill");
- return;
+ alloc_size = (size_t) (((struct sockaddr_un *) 0)->sun_path) +
+ strlen(name) + 1;
+
+ addr = malloc(alloc_size);
+ if (addr < 0) {
+ ERR("allocating addr failed");
+ return NULL;
}
- sleep(1);
+ addr->sun_family = AF_UNIX;
+ strcpy(addr->sun_path, name);
+
+ *sock_addr_size = alloc_size;
+
+ return addr;
}
-/* 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
- */
+struct ustcomm_sock * ustcomm_init_sock(int fd, int epoll_fd,
+ struct list_head *list)
+{
+ struct epoll_event ev;
+ struct ustcomm_sock *sock;
+
+ sock = malloc(sizeof(struct ustcomm_sock));
+ if (!sock) {
+ perror("malloc: couldn't allocate ustcomm_sock");
+ return NULL;
+ }
-int send_message(pid_t pid, const char *msg, char **reply)
+ ev.events = EPOLLIN;
+ ev.data.ptr = sock;
+ sock->fd = fd;
+
+ if (epoll_ctl(epoll_fd, EPOLL_CTL_ADD, sock->fd, &ev) == -1) {
+ perror("epoll_ctl: failed to add socket\n");
+ free(sock);
+ return NULL;
+ }
+
+ sock->epoll_fd = epoll_fd;
+ if (list) {
+ list_add(&sock->list, list);
+ } else {
+ INIT_LIST_HEAD(&sock->list);
+ }
+
+ return sock;
+}
+
+void ustcomm_del_sock(struct ustcomm_sock *sock, int keep_in_epoll)
+{
+ list_del(&sock->list);
+ if (!keep_in_epoll) {
+ if (epoll_ctl(sock->epoll_fd, EPOLL_CTL_DEL, sock->fd, NULL) == -1) {
+ PERROR("epoll_ctl: failed to delete socket");
+ }
+ }
+ close(sock->fd);
+ free(sock);
+}
+
+struct ustcomm_sock * ustcomm_init_named_socket(const char *name,
+ int epoll_fd)
{
- int fd;
int result;
- struct sockaddr_un addr;
+ int fd;
+ size_t sock_addr_size;
+ struct sockaddr_un * addr;
+ struct ustcomm_sock *sock;
- result = fd = socket(PF_UNIX, SOCK_DGRAM, 0);
- if(result == -1) {
- perror("socket");
- return -1;
+ fd = socket(PF_UNIX, SOCK_STREAM, 0);
+ if(fd == -1) {
+ PERROR("socket");
+ return NULL;
}
- addr.sun_family = AF_UNIX;
+ addr = create_sock_addr(name, &sock_addr_size);
+ if (addr == NULL) {
+ ERR("allocating addr, UST thread bailing");
+ goto close_sock;
+ }
- result = snprintf(addr.sun_path, UNIX_PATH_MAX, "%s/%d", SOCK_DIR, pid);
- if(result >= UNIX_PATH_MAX) {
- fprintf(stderr, "string overflow allocating socket name");
- return -1;
+ result = access(name, F_OK);
+ if(result == 0) {
+ /* file exists */
+ result = unlink(name);
+ if(result == -1) {
+ PERROR("unlink of socket file");
+ goto free_addr;
+ }
+ DBG("socket already exists; overwriting");
}
- signal_process(pid);
+ result = bind(fd, (struct sockaddr *)addr, sock_addr_size);
+ if(result == -1) {
+ PERROR("bind");
+ goto free_addr;
+ }
- result = sendto(fd, msg, strlen(msg), 0, (struct sockaddr *)&addr, sizeof(addr));
+ result = listen(fd, 1);
if(result == -1) {
- perror("sendto");
+ PERROR("listen");
+ goto free_addr;
+ }
+
+ sock = ustcomm_init_sock(fd, epoll_fd,
+ NULL);
+ if (!sock) {
+ ERR("failed to create ustcomm_sock");
+ goto free_addr;
+ }
+
+ free(addr);
+
+ return sock;
+
+free_addr:
+ free(addr);
+close_sock:
+ close(fd);
+
+ return NULL;
+}
+
+void ustcomm_del_named_sock(struct ustcomm_sock *sock,
+ int keep_socket_file)
+{
+ int result, fd;
+ struct stat st;
+ struct sockaddr dummy;
+ struct sockaddr_un *sockaddr = NULL;
+ int alloc_size;
+
+ fd = sock->fd;
+
+ if(!keep_socket_file) {
+
+ /* Get the socket name */
+ alloc_size = sizeof(dummy);
+ if (getsockname(fd, &dummy, (socklen_t *)&alloc_size) < 0) {
+ PERROR("getsockname failed");
+ goto del_sock;
+ }
+
+ sockaddr = zmalloc(alloc_size);
+ if (!sockaddr) {
+ ERR("failed to allocate sockaddr");
+ goto del_sock;
+ }
+
+ if (getsockname(fd, sockaddr, (socklen_t *)&alloc_size) < 0) {
+ PERROR("getsockname failed");
+ goto free_sockaddr;
+ }
+
+ /* Destroy socket */
+ result = stat(sockaddr->sun_path, &st);
+ if(result < 0) {
+ PERROR("stat (%s)", sockaddr->sun_path);
+ goto free_sockaddr;
+ }
+
+ /* Paranoid check before deleting. */
+ result = S_ISSOCK(st.st_mode);
+ if(!result) {
+ ERR("The socket we are about to delete is not a socket.");
+ goto free_sockaddr;
+ }
+
+ result = unlink(sockaddr->sun_path);
+ if(result < 0) {
+ PERROR("unlink");
+ }
+ }
+
+free_sockaddr:
+ free(sockaddr);
+
+del_sock:
+ ustcomm_del_sock(sock, keep_socket_file);
+}
+
+
+/* Called by an app to ask the consumer daemon to connect to it. */
+
+int ustcomm_request_consumer(pid_t pid, const char *channel)
+{
+ int result, daemon_fd;
+ int retval = 0;
+ char *msg=NULL;
+ char *explicit_daemon_socket_path, *daemon_path;
+
+ explicit_daemon_socket_path = getenv("UST_DAEMON_SOCKET");
+ if (explicit_daemon_socket_path) {
+ /* user specified explicitly a socket path */
+ result = asprintf(&daemon_path, "%s", explicit_daemon_socket_path);
+ } else {
+ /* just use the default path */
+ result = asprintf(&daemon_path, "%s/ustd", SOCK_DIR);
+ }
+ if (result < 0) {
+ ERR("string overflow allocating socket name");
return -1;
}
- if(!reply)
+ if (asprintf(&msg, "collect %d %s", pid, channel) < 0) {
+ ERR("ustcomm_request_consumer : asprintf failed (collect %d/%s)",
+ pid, channel);
+ retval = -1;
+ goto free_daemon_path;
+ }
+
+ result = ustcomm_connect_path(daemon_path, &daemon_fd);
+ if (result < 0) {
+ WARN("ustcomm_connect_path failed, daemon_path: %s",
+ daemon_path);
+ retval = -1;
+ goto del_string;
+ }
+
+ result = ustcomm_send_request(daemon_fd, msg, NULL);
+ if (result < 0) {
+ WARN("ustcomm_send_request failed, daemon path: %s",
+ daemon_path);
+ retval = -1;
+ }
+
+ close(daemon_fd);
+del_string:
+ free(msg);
+free_daemon_path:
+ free(daemon_path);
+
+ return retval;
+}
+
+/* returns 1 to indicate a message was received
+ * returns 0 to indicate no message was received (end of stream)
+ * returns -1 to indicate an error
+ */
+int ustcomm_recv_fd(int sock,
+ struct ustcomm_header *header,
+ char **data, int *fd)
+{
+ int result;
+ int retval;
+ struct ustcomm_header peek_header;
+ struct iovec iov[2];
+ struct msghdr msg;
+ struct cmsghdr *cmsg;
+ char buf[CMSG_SPACE(sizeof(int))];
+
+ result = recv(sock, &peek_header, sizeof(peek_header),
+ MSG_PEEK | MSG_WAITALL);
+ if (result <= 0) {
+ if(errno == ECONNRESET) {
+ return 0;
+ } else if (errno == EINTR) {
+ return -1;
+ } else if (result < 0) {
+ PERROR("recv");
+ return -1;
+ }
return 0;
+ }
- *reply = (char *) malloc(MSG_MAX+1);
- result = recvfrom(fd, *reply, MSG_MAX, 0, NULL, NULL);
- if(result == -1) {
- perror("recvfrom");
- return -1;
+ memset(&msg, 0, sizeof(msg));
+
+ iov[0].iov_base = (char *)header;
+ iov[0].iov_len = sizeof(struct ustcomm_header);
+
+ msg.msg_iov = iov;
+ msg.msg_iovlen = 1;
+
+ if (peek_header.size) {
+ if (peek_header.size < 0 || peek_header.size > 100) {
+ WARN("big peek header! %d", peek_header.size);
+ }
+ *data = malloc(peek_header.size);
+ if (!*data) {
+ ERR("failed to allocate space for message");
+ }
+
+ iov[1].iov_base = (char *)*data;
+ iov[1].iov_len = peek_header.size;
+
+ msg.msg_iovlen++;
}
-
- (*reply)[result] = '\0';
- return 0;
+ if (fd && peek_header.fd_included) {
+ msg.msg_control = buf;
+ msg.msg_controllen = sizeof(buf);
+ }
+
+ result = recvmsg(sock, &msg,
+ MSG_WAITALL);
+
+ if (result <= 0) {
+ if(errno == ECONNRESET) {
+ retval = 0;
+ } else if (errno == EINTR) {
+ retval = -1;
+ } else if (result < 0) {
+ PERROR("recv");
+ retval = -1;
+ } else {
+ retval = 0;
+ }
+ free(*data);
+ return retval;
+ }
+
+ if (fd && peek_header.fd_included) {
+ cmsg = CMSG_FIRSTHDR(&msg);
+ result = 0;
+ while (cmsg != NULL) {
+ if (cmsg->cmsg_level == SOL_SOCKET
+ && cmsg->cmsg_type == SCM_RIGHTS) {
+ *fd = *(int *) CMSG_DATA(cmsg);
+ result = 1;
+ break;
+ }
+ cmsg = CMSG_NXTHDR(&msg, cmsg);
+ }
+ if (!result) {
+ ERR("Failed to receive file descriptor\n");
+ }
+ }
+
+ return 1;
}
-int ustcomm_app_recv_message(struct ustcomm_app *app, char **msg)
+int ustcomm_recv(int sock,
+ struct ustcomm_header *header,
+ char **data)
{
- int fd;
+ return ustcomm_recv_fd(sock, header, data, NULL);
+}
+
+
+int recv_message_conn(int sock, char **msg)
+{
+ struct ustcomm_header header;
+
+ return ustcomm_recv(sock, &header, msg);
+}
+
+int ustcomm_send_fd(int sock,
+ const struct ustcomm_header *header,
+ const char *data,
+ int *fd)
+{
+ struct iovec iov[2];
+ struct msghdr msg;
int result;
- struct sockaddr_un addr;
+ struct cmsghdr *cmsg;
+ char buf[CMSG_SPACE(sizeof(int))];
- *msg = (char *) malloc(MSG_MAX+1);
- result = recvfrom(app->fd, *msg, MSG_MAX, 0, NULL, NULL);
- if(result == -1) {
- PERROR("recvfrom");
- return -1;
+ memset(&msg, 0, sizeof(msg));
+
+ iov[0].iov_base = (char *)header;
+ iov[0].iov_len = sizeof(struct ustcomm_header);
+
+ msg.msg_iov = iov;
+ msg.msg_iovlen = 1;
+
+ if (header->size) {
+ iov[1].iov_base = (char *)data;
+ iov[1].iov_len = header->size;
+
+ msg.msg_iovlen++;
+
+ }
+
+ if (fd && header->fd_included) {
+ msg.msg_control = buf;
+ msg.msg_controllen = sizeof(buf);
+ cmsg = CMSG_FIRSTHDR(&msg);
+ cmsg->cmsg_level = SOL_SOCKET;
+ cmsg->cmsg_type = SCM_RIGHTS;
+ cmsg->cmsg_len = CMSG_LEN(sizeof(int));
+ *(int *) CMSG_DATA(cmsg) = *fd;
+ msg.msg_controllen = cmsg->cmsg_len;
+ }
+
+ result = sendmsg(sock, &msg, MSG_NOSIGNAL);
+ if (result < 0 && errno != EPIPE) {
+ PERROR("sendmsg failed");
+ }
+ return result;
+}
+
+int ustcomm_send(int sock,
+ const struct ustcomm_header *header,
+ const char *data)
+{
+ return ustcomm_send_fd(sock, header, data, NULL);
+}
+
+int ustcomm_send_reply(char *msg, int sock)
+{
+ int result;
+ struct ustcomm_header header;
+
+ memset(&header, 0, sizeof(header));
+
+ header.size = strlen(msg) + 1;
+
+ result = ustcomm_send(sock, &header, msg);
+ if(result < 0) {
+ ERR("error in ustcomm_send");
+ return result;
}
-
- DBG("ustcomm_app_recv_message: result is %d, message[1] is %hhd", result, (*msg)[1]);
- (*msg)[result] = '\0';
return 0;
}
-static int init_named_socket(char *name, char **path_out)
+int ustcomm_send_req(int sock,
+ const struct ustcomm_header *req_header,
+ const char *data,
+ char **response)
{
int result;
- int fd;
+ struct ustcomm_header res_header;
- struct sockaddr_un addr;
-
- result = fd = socket(PF_UNIX, SOCK_DGRAM, 0);
- if(result == -1) {
+ result = ustcomm_send(sock, req_header, data);
+ if ( result <= 0) {
+ return result;
+ }
+
+ if (!response) {
+ return 1;
+ }
+
+ return ustcomm_recv(sock,
+ &res_header,
+ response);
+
+}
+
+/*
+ * Return value:
+ * 0: Success, but no reply because recv() returned 0
+ * 1: Success
+ * -1: Error
+ *
+ * On error, the error message is printed, except on
+ * ECONNRESET, which is normal when the application dies.
+ */
+
+int ustcomm_send_request(int sock, const char *req, char **reply)
+{
+ struct ustcomm_header req_header;
+
+ req_header.size = strlen(req) + 1;
+
+ return ustcomm_send_req(sock,
+ &req_header,
+ req,
+ reply);
+
+}
+
+/* Return value:
+ * 0: success
+ * -1: error
+ */
+
+int ustcomm_connect_path(const char *name, int *connection_fd)
+{
+ int result, fd;
+ size_t sock_addr_size;
+ struct sockaddr_un *addr;
+
+ fd = socket(PF_UNIX, SOCK_STREAM, 0);
+ if(fd == -1) {
PERROR("socket");
return -1;
}
- addr.sun_family = AF_UNIX;
-
- strncpy(addr.sun_path, name, UNIX_PATH_MAX);
- addr.sun_path[UNIX_PATH_MAX-1] = '\0';
+ addr = create_sock_addr(name, &sock_addr_size);
+ if (addr == NULL) {
+ ERR("allocating addr failed");
+ goto close_sock;
+ }
- result = bind(fd, (struct sockaddr *)&addr, sizeof(addr));
+ result = connect(fd, (struct sockaddr *)addr, sock_addr_size);
if(result == -1) {
- PERROR("bind");
- goto close_sock;
+ PERROR("connect (path=%s)", name);
+ goto free_sock_addr;
}
- if(path_out)
- *path_out = strdupa(addr.sun_path);
+ *connection_fd = fd;
- return fd;
+ free(addr);
- close_sock:
+ return 0;
+
+free_sock_addr:
+ free(addr);
+close_sock:
close(fd);
return -1;
}
-int ustcomm_init_app(pid_t pid, struct ustcomm_app *handle)
+
+/* Open a connection to a traceable app.
+ *
+ * Return value:
+ * 0: success
+ * -1: error
+ */
+
+int ustcomm_connect_app(pid_t pid, int *app_fd)
{
int result;
+ int retval = 0;
char *name;
- result = asprintf(&name, "%s/%d", SOCK_DIR, (int)pid);
- if(result >= UNIX_PATH_MAX) {
- ERR("string overflow allocating socket name");
+ result = asprintf(&name, "%s/%d", SOCK_DIR, pid);
+ if (result < 0) {
+ ERR("failed to allocate socket name");
return -1;
}
- handle->fd = init_named_socket(name, &handle->socketpath);
- if(handle->fd < 0) {
- goto free_name;
+ result = ustcomm_connect_path(name, app_fd);
+ if (result < 0) {
+ ERR("failed to connect to app");
+ retval = -1;
}
+
free(name);
+ return retval;
+}
+
+int ensure_dir_exists(const char *dir)
+{
+ struct stat st;
+ int result;
+
+ if(!strcmp(dir, ""))
+ return -1;
+
+ result = stat(dir, &st);
+ if(result == -1 && errno != ENOENT) {
+ return -1;
+ }
+ else if(result == -1) {
+ /* ENOENT */
+ int result;
+
+ /* mkdir mode to 0777 */
+ result = mkdir_p(dir, S_IRWXU | S_IRWXG | S_IRWXO);
+ if(result != 0) {
+ ERR("executing in recursive creation of directory %s", dir);
+ return -1;
+ }
+ }
+
return 0;
+}
-free_name:
- free(name);
- return -1;
+/* Used by the daemon to initialize its server so applications
+ * can connect to it.
+ */
+
+
+static const char *find_tok(const char *str)
+{
+ while(*str == ' ') {
+ str++;
+
+ if(*str == 0)
+ return NULL;
+ }
+
+ return str;
}
-int ustcomm_init_ustd(struct ustcomm_ustd *handle)
+static const char *find_sep(const char *str)
{
- handle->fd = init_named_socket("ustd", &handle->socketpath);
- if(handle->fd < 0)
- return handle->fd;
+ while(*str != ' ') {
+ str++;
- return 0;
+ if(*str == 0)
+ break;
+ }
+
+ return str;
+}
+
+int nth_token_is(const char *str, const char *token, int tok_no)
+{
+ int i;
+ const char *start;
+ const 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(const char *str, int tok_no)
+{
+ static char *retval = NULL;
+ int i;
+ const char *start;
+ const 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;
+ }
+
+ if (asprintf(&retval, "%.*s", (int)(end-start), start) < 0) {
+ ERR("nth_token : asprintf failed (%.*s)",
+ (int)(end-start), start);
+ return NULL;
+ }
+
+ return retval;
}