linux: clean some more compiler warnings

gcc-12 and clang-14 no longer emit any errors

diff --git a/src/if-linux.c b/src/if-linux.c
index 057eaf89394127cc66224895c300a7eb041e9afd..3ca967055d5d6cda2f228efd38dc564daecfb33d 100644 (file)
--- a/src/if-linux.c
+++ b/src/if-linux.c
@@ -554,15 +554,15 @@ if_getnetlink(struct dhcpcd_ctx *ctx, struct iovec *iov, int fd, int flags,
            .msg_name = &nladdr, .msg_namelen = sizeof(nladdr),
            .msg_iov = iov, .msg_iovlen = 1,
        };
-       ssize_t len;
+       size_t len;
        struct nlmsghdr *nlm;
        int r = 0;
        unsigned int again;
        bool terminated;
 
 recv_again:
-       len = recvmsg(fd, &msg, flags);
-       if (len == -1 || len == 0)
+       len = (size_t)recvmsg(fd, &msg, flags);
+       if (len == 0 || (ssize_t)len == -1)
                return (int)len;
 
        /* Check sender */
@@ -578,7 +578,7 @@ recv_again:
        again = 0;
        terminated = false;
        for (nlm = iov->iov_base;
-            nlm && NLMSG_OK(nlm, (size_t)len);
+            nlm && NLMSG_OK(nlm, len);
             nlm = NLMSG_NEXT(nlm, len))
        {
                again = (nlm->nlmsg_flags & NLM_F_MULTI);
@@ -1143,7 +1143,8 @@ if_sendnetlink(struct dhcpcd_ctx *ctx, int protocol, struct nlmsghdr *hdr,
 }
 
 #define NLMSG_TAIL(nmsg)                                               \
-       ((struct rtattr *)(((ptrdiff_t)(nmsg))+NLMSG_ALIGN((nmsg)->nlmsg_len)))
+       ((struct rtattr *)(void *)(((char *)(nmsg)) + \
+           NLMSG_ALIGN((nmsg)->nlmsg_len)))
 
 static int
 add_attr_l(struct nlmsghdr *n, unsigned short maxlen, unsigned short type,