socketutils: add const qualifier to variables

* socketutils.c (cache_and_print_inode_details): Make "details"
parameter const.
(print_sockaddr_by_inode_cached): Make "e" variable const.
(inet_send_query): Make struct nlmsghdr and struct inet_diag_req_v2
members const.  Make "msg" variable const.
(inet_parse_response): Make "data" parameter and diag_msg variable const.
(receive_responses): Make "h" and "rc" variables const.
(unix_send_query): Make struct nlmsghdr and struct unix_diag_req
members const.  Make "msg" variable const.
(unix_print): Make all parameters const.
(print_sockaddr_by_inode): Make proto_name parameter const.

diff --git a/socketutils.c b/socketutils.c
index 6e56228b73a62afa9eb7966739cf1ca5386c1f96..43758424a9a32019db881bdf8e1feacd866f0bc3 100644 (file)
--- a/socketutils.c
+++ b/socketutils.c
@@ -55,7 +55,7 @@ static cache_entry cache[CACHE_SIZE];
 #define CACHE_MASK (CACHE_SIZE - 1)
 
 static int
-cache_and_print_inode_details(const unsigned long inode, char *details)
+cache_and_print_inode_details(const unsigned long inode, char *const details)
 {
        cache_entry *e = &cache[inode & CACHE_MASK];
        free(e->details);
@@ -69,7 +69,7 @@ cache_and_print_inode_details(const unsigned long inode, char *details)
 bool
 print_sockaddr_by_inode_cached(const unsigned long inode)
 {
-       const cache_entry *e = &cache[inode & CACHE_MASK];
+       const cache_entry *const e = &cache[inode & CACHE_MASK];
        if (e && inode == e->inode) {
                tprints(e->details);
                return true;
@@ -84,8 +84,8 @@ inet_send_query(const int fd, const int family, const int proto)
                .nl_family = AF_NETLINK
        };
        struct {
-               struct nlmsghdr nlh;
-               struct inet_diag_req_v2 idr;
+               const struct nlmsghdr nlh;
+               const struct inet_diag_req_v2 idr;
        } req = {
                .nlh = {
                        .nlmsg_len = sizeof(req),
@@ -102,8 +102,8 @@ inet_send_query(const int fd, const int family, const int proto)
                .iov_base = &req,
                .iov_len = sizeof(req)
        };
-       struct msghdr msg = {
-               .msg_name = (void *) &nladdr,
+       const struct msghdr msg = {
+               .msg_name = &nladdr,
                .msg_namelen = sizeof(nladdr),
                .msg_iov = &iov,
                .msg_iovlen = 1
@@ -120,10 +120,10 @@ inet_send_query(const int fd, const int family, const int proto)
 }
 
 static int
-inet_parse_response(const char *proto_name, const void *data,
+inet_parse_response(const char *const proto_name, const void *const data,
                    const int data_len, const unsigned long inode)
 {
-       const struct inet_diag_msg *diag_msg = data;
+       const struct inet_diag_msg *const diag_msg = data;
        static const char zero_addr[sizeof(struct in6_addr)];
        socklen_t addr_size, text_size;
 
@@ -190,29 +190,28 @@ receive_responses(const int fd, const unsigned long inode,
        int flags = 0;
 
        for (;;) {
-               ssize_t ret;
                struct msghdr msg = {
-                       .msg_name = (void *) &nladdr,
+                       .msg_name = &nladdr,
                        .msg_namelen = sizeof(nladdr),
                        .msg_iov = &iov,
                        .msg_iovlen = 1
                };
 
-               ret = recvmsg(fd, &msg, flags);
+               ssize_t ret = recvmsg(fd, &msg, flags);
                if (ret < 0) {
                        if (errno == EINTR)
                                continue;
                        return false;
                }
 
-               struct nlmsghdr *h = (struct nlmsghdr *) buf;
+               const struct nlmsghdr *h = (struct nlmsghdr *) buf;
                if (!NLMSG_OK(h, ret))
                        return false;
                for (; NLMSG_OK(h, ret); h = NLMSG_NEXT(h, ret)) {
                        if (h->nlmsg_type != SOCK_DIAG_BY_FAMILY)
                                return false;
-                       int rc = parser(proto_name, NLMSG_DATA(h),
-                                       h->nlmsg_len, inode);
+                       const int rc = parser(proto_name, NLMSG_DATA(h),
+                                             h->nlmsg_len, inode);
                        if (rc > 0)
                                return true;
                        if (rc < 0)
@@ -237,8 +236,8 @@ unix_send_query(const int fd, const unsigned long inode)
                .nl_family = AF_NETLINK
        };
        struct {
-               struct nlmsghdr nlh;
-               struct unix_diag_req udr;
+               const struct nlmsghdr nlh;
+               const struct unix_diag_req udr;
        } req = {
                .nlh = {
                        .nlmsg_len = sizeof(req),
@@ -257,8 +256,8 @@ unix_send_query(const int fd, const unsigned long inode)
                .iov_base = &req,
                .iov_len = sizeof(req)
        };
-       struct msghdr msg = {
-               .msg_name = (void *) &nladdr,
+       const struct msghdr msg = {
+               .msg_name = &nladdr,
                .msg_namelen = sizeof(nladdr),
                .msg_iov = &iov,
                .msg_iovlen = 1
@@ -352,7 +351,7 @@ unix_parse_response(const char *proto_name, const void *data,
 }
 
 static bool
-unix_print(int fd, const unsigned long inode)
+unix_print(const int fd, const unsigned long inode)
 {
        return unix_send_query(fd, inode)
                && receive_responses(fd, inode, "UNIX", unix_parse_response);
@@ -385,7 +384,7 @@ udp_v6_print(const int fd, const unsigned long inode)
 /* Given an inode number of a socket, print out the details
  * of the ip address and port. */
 bool
-print_sockaddr_by_inode(const unsigned long inode, const char *proto_name)
+print_sockaddr_by_inode(const unsigned long inode, const char *const proto_name)
 {
        static const struct {
                const char *const name;