Header Alignment Cleanups

[lttng-tools.git] / liblttsessiondcomm / liblttsessiondcomm.c

diff --git a/liblttsessiondcomm/liblttsessiondcomm.c b/liblttsessiondcomm/liblttsessiondcomm.c
index 449a1fbed179045f51d5472ced2bf1bb054928ee..cecd89d6a5815fc7ee1e472821474afc4785dc39 100644 (file)
--- a/liblttsessiondcomm/liblttsessiondcomm.c
+++ b/liblttsessiondcomm/liblttsessiondcomm.c
@@ -3,8 +3,8 @@
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version 2
- * of the License, or (at your option) any later version.
+ * as published by the Free Software Foundation; only version 2
+ * of the License.
  * 
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ -26,8 +26,9 @@
 #include <sys/types.h>
 #include <sys/un.h>
 #include <unistd.h>
+#include <assert.h>
 
-#include "liblttsessiondcomm.h"
+#include <lttng/lttng-sessiond-comm.h>
 
 /*
  * Human readable error message.
@@ -114,28 +115,36 @@ int lttcomm_connect_unix_sock(const char *pathname)
 {
        struct sockaddr_un sun;
        int fd;
-       int ret = 1;
+       int ret;
 
        fd = socket(PF_UNIX, SOCK_STREAM, 0);
        if (fd < 0) {
                perror("socket");
+               ret = fd;
                goto error;
        }
 
        memset(&sun, 0, sizeof(sun));
        sun.sun_family = AF_UNIX;
        strncpy(sun.sun_path, pathname, sizeof(sun.sun_path));
+       sun.sun_path[sizeof(sun.sun_path) - 1] = '\0';
 
        ret = connect(fd, (struct sockaddr *) &sun, sizeof(sun));
        if (ret < 0) {
-               perror("connect");
-               goto error;
+               /*
+                * Don't print message on connect error, because connect
+                * is used in normal execution to detect if sessiond is
+                * alive.
+                */
+               goto error_connect;
        }
 
        return fd;
 
+error_connect:
+       close(fd);
 error:
-       return -1;
+       return ret;
 }
 
 /*
@@ -183,8 +192,11 @@ int lttcomm_create_unix_sock(const char *pathname)
 
        memset(&sun, 0, sizeof(sun));
        sun.sun_family = AF_UNIX;
-       strncpy(sun.sun_path, pathname, strlen(pathname));
+       strncpy(sun.sun_path, pathname, sizeof(sun.sun_path));
+       sun.sun_path[sizeof(sun.sun_path) - 1] = '\0';
 
+       /* Unlink the old file if present */
+       (void) unlink(pathname);
        ret = bind(fd, (struct sockaddr *) &sun, sizeof(sun));
        if (ret < 0) {
                perror("bind");
@@ -223,12 +235,10 @@ int lttcomm_listen_unix_sock(int sock)
  */
 ssize_t lttcomm_recv_unix_sock(int sock, void *buf, size_t len)
 {
-       struct msghdr msg;
+       struct msghdr msg = { 0 };
        struct iovec iov[1];
        ssize_t ret = -1;
 
-       memset(&msg, 0, sizeof(msg));
-
        iov[0].iov_base = buf;
        iov[0].iov_len = len;
        msg.msg_iov = iov;
@@ -250,12 +260,10 @@ ssize_t lttcomm_recv_unix_sock(int sock, void *buf, size_t len)
  */
 ssize_t lttcomm_send_unix_sock(int sock, void *buf, size_t len)
 {
-       struct msghdr msg;
+       struct msghdr msg = { 0 };
        struct iovec iov[1];
        ssize_t ret = -1;
 
-       memset(&msg, 0, sizeof(msg));
-
        iov[0].iov_base = buf;
        iov[0].iov_len = len;
        msg.msg_iov = iov;
@@ -294,23 +302,29 @@ int lttcomm_close_unix_sock(int sock)
  */
 ssize_t lttcomm_send_fds_unix_sock(int sock, void *buf, int *fds, size_t nb_fd, size_t len)
 {
-       struct msghdr msg;
+       struct msghdr msg = { 0 };
        struct cmsghdr *cmptr;
        struct iovec iov[1];
        ssize_t ret = -1;
        unsigned int sizeof_fds = nb_fd * sizeof(int);
        char tmp[CMSG_SPACE(sizeof_fds)];
 
-       memset(&msg, 0, sizeof(msg));
+       /*
+        * Note: the consumerd receiver only supports receiving one FD per
+        * message.
+        */
+       assert(nb_fd == 1);
 
        msg.msg_control = (caddr_t)tmp;
        msg.msg_controllen = CMSG_LEN(sizeof_fds);
 
        cmptr = CMSG_FIRSTHDR(&msg);
-       cmptr->cmsg_len = CMSG_LEN(sizeof_fds);
        cmptr->cmsg_level = SOL_SOCKET;
        cmptr->cmsg_type = SCM_RIGHTS;
+       cmptr->cmsg_len = CMSG_LEN(sizeof_fds);
        memcpy(CMSG_DATA(cmptr), fds, sizeof_fds);
+       /* Sum of the length of all control messages in the buffer: */
+       msg.msg_controllen = cmptr->cmsg_len;
 
        iov[0].iov_base = buf;
        iov[0].iov_len = len;