poll: Avoid duplicate array index counting

Calculate remain from idx at the top of the loop.  This avoids having
to keep both remain and idx in step.

Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk>

diff --git a/secnet.c b/secnet.c
index 7a9d3f0..6d08323 100644 (file)
--- a/secnet.c
+++ b/secnet.c
@@ -291,7 +291,7 @@ uint64_t now_global;
 static void run(void)
 {
     struct poll_interest *i;
-    int rv, nfds, remain, idx;
+    int rv, nfds, idx;
     int timeout;
     struct pollfd *fds=0;
     int allocdfds=0, shortfall=0;
@@ -320,11 +320,11 @@ static void run(void)
            allocdfds += shortfall;
            fds=safe_realloc_ary(fds,sizeof(*fds),allocdfds, "run");
        }
-       remain=allocdfds;
        shortfall=0;
        idx=0;
        timeout=-1;
        LIST_FOREACH(i, &reg, entry) {
+           int remain=allocdfds-idx;
            nfds=remain;
            rv=i->before(i->state, fds+idx, &nfds, &timeout);
            if (rv!=0) {
@@ -340,7 +340,6 @@ static void run(void)
                      i->desc,timeout);
            }
            idx+=nfds;
-           remain-=nfds;
            i->nfds=nfds;
        }
        do {