poll: Avoid duplicate array index counting

[secnet.git] / secnet.c

diff --git a/secnet.c b/secnet.c
index 465a93fc260404cad1eb2070bf8df446013e87a9..6d08323ff5152fae567d5bd87972cf0f9097bb71 100644 (file)
--- a/secnet.c
+++ b/secnet.c
@@ -42,10 +42,9 @@ struct poll_interest {
     int32_t max_nfds;
     int32_t nfds;
     cstring_t desc;
-    struct poll_interest *next;
+    LIST_ENTRY(poll_interest) entry;
 };
-static struct poll_interest *reg=NULL;
-static int32_t total_nfds=10;
+static LIST_HEAD(, poll_interest) reg = LIST_HEAD_INITIALIZER(&reg);
 
 static bool_t finished=False;
 
@@ -239,10 +238,7 @@ void register_for_poll(void *st, beforepoll_fn *before,
     i->max_nfds=max_nfds;
     i->nfds=0;
     i->desc=desc;
-    assert(total_nfds < INT_MAX - max_nfds);
-    total_nfds+=max_nfds;
-    i->next=reg;
-    reg=i;
+    LIST_INSERT_HEAD(&reg, i, entry);
     return;
 }
 
@@ -295,11 +291,10 @@ 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;
-
-    fds=safe_malloc(sizeof(*fds)*total_nfds, "run");
+    struct pollfd *fds=0;
+    int allocdfds=0, shortfall=0;
 
     Message(M_NOTICE,"%s [%d]: starting\n",version,secnet_pid);
 
@@ -310,7 +305,7 @@ static void run(void)
        now_global=((uint64_t)tv_now_global.tv_sec*(uint64_t)1000)+
                   ((uint64_t)tv_now_global.tv_usec/(uint64_t)1000);
        idx=0;
-       for (i=reg; i; i=i->next) {
+       LIST_FOREACH(i, &reg, entry) {
            int check;
            for (check=0; check<i->nfds; check++) {
                if(fds[idx+check].revents & POLLNVAL) {
@@ -320,22 +315,31 @@ static void run(void)
            i->after(i->state, fds+idx, i->nfds);
            idx+=i->nfds;
        }
-       remain=total_nfds;
+       if (shortfall) {
+           allocdfds *= 2;
+           allocdfds += shortfall;
+           fds=safe_realloc_ary(fds,sizeof(*fds),allocdfds, "run");
+       }
+       shortfall=0;
        idx=0;
        timeout=-1;
-       for (i=reg; i; i=i->next) {
+       LIST_FOREACH(i, &reg, entry) {
+           int remain=allocdfds-idx;
            nfds=remain;
            rv=i->before(i->state, fds+idx, &nfds, &timeout);
            if (rv!=0) {
-               /* XXX we need to handle this properly: increase the
-                  nfds available */
-               fatal("run: beforepoll_fn (%s) returns %d",i->desc,rv);
+               if (rv!=ERANGE)
+                   fatal("run: beforepoll_fn (%s) returns %d",i->desc,rv);
+               assert(nfds < INT_MAX/4 - shortfall);
+               shortfall += nfds-remain;
+               nfds=0;
+               timeout=0;
            }
            if (timeout<-1) {
-               fatal("run: beforepoll_fn (%s) set timeout to %d",timeout);
+               fatal("run: beforepoll_fn (%s) set timeout to %d",
+                     i->desc,timeout);
            }
            idx+=nfds;
-           remain-=nfds;
            i->nfds=nfds;
        }
        do {
@@ -402,9 +406,7 @@ static void become_daemon(void)
     }
     if (secnet_is_daemon) {
        /* stderr etc are redirected to the system/log facility */
-       if (pipe(errfds)!=0) {
-           fatal_perror("can't create pipe for stderr");
-       }
+       pipe_cloexec(errfds);
        if (dup2(errfds[1],0) < 0
            || dup2(errfds[1],1) < 0
            || dup2(errfds[1],2) < 0)