fakeidentd: fix daemon mode (was thinking that it is in

inetd-wait mode and dying after timeout). Minor fixes,
comments are improved in places. 

2 files changed, 27 insertions, 23 deletions

diff --git a/networking/isrv.c b/networking/isrv.c
index 02ca1d787..5193f30f3 100644
--- a/networking/isrv.c
+++ b/networking/isrv.c
@@ -21,6 +21,8 @@
 
 /* Helpers */
 
+/* Even if _POSIX_MONOTONIC_CLOCK is defined, this
+ * may require librt */
 #if 0 /*def _POSIX_MONOTONIC_CLOCK*/
 static time_t monotonic_time(void)
 {
@@ -194,7 +196,8 @@ static void handle_accept(isrv_state_t *state, int fd)
         if (newfd < 0) {
                 if (errno == EAGAIN) return;
                 /* Most probably someone gave us wrong fd type
-                 * (for example, non-socket) */
+                 * (for example, non-socket). Don't want
+                 * to loop forever. */
                 bb_perror_msg_and_die("accept");
         }
 
@@ -210,6 +213,7 @@ static void handle_fd_set(isrv_state_t *state, fd_set *fds, int (*h)(int, void *
         enum { LONG_CNT = sizeof(fd_set) / sizeof(long) };
         int fds_pos;
         int fd, peer;
+        /* need to know value at _the beginning_ of this routine */
         int fd_cnt = FD_COUNT;
 
         if (LONG_CNT * sizeof(long) != sizeof(fd_set))
@@ -235,10 +239,15 @@ static void handle_fd_set(isrv_state_t *state, fd_set *fds, int (*h)(int, void *
                 }
                 break; /* all words are zero */
  found_fd:
-                if (fd >= fd_cnt) /* paranoia */
+                if (fd >= fd_cnt) { /* paranoia */
+                        DPRINTF("handle_fd_set: fd > fd_cnt?? (%d > %d)",
+                                        fd, fd_cnt);
                         break;
+                }
                 DPRINTF("handle_fd_set: fd %d is active", fd);
                 peer = FD2PEER[fd];
+                if (peer < 0)
+                        continue; /* peer is already gone */
                 if (peer == 0) {
                         handle_accept(state, fd);
                         continue;
@@ -259,9 +268,9 @@ static void handle_timeout(isrv_state_t *state, int (*do_timeout)(void **))
         peer = PEER_COUNT-1;
         /* peer 0 is not checked */
         while (peer > 0) {
-                DPRINTF("peer %d: time diff %d", peer, (int)(CURTIME - TIMEO_TBL[peer]));
-
-                if ((CURTIME - TIMEO_TBL[peer]) > TIMEOUT) {
+                DPRINTF("peer %d: time diff %d", peer,
+                                (int)(CURTIME - TIMEO_TBL[peer]));
+                if ((CURTIME - TIMEO_TBL[peer]) >= TIMEOUT) {
                         DPRINTF("peer %d: do_timeout()", peer);
                         n = do_timeout(&PARAM_TBL[peer]);
                         if (n)
@@ -279,7 +288,7 @@ void isrv_run(
         int (*do_wr)(int fd, void **),
         int (*do_timeout)(void **),
         int timeout,
-        int exit_if_no_clients)
+        int linger_timeout)
 {
         isrv_state_t *state = xzalloc(sizeof(*state));
         state->new_peer = new_peer;
@@ -300,6 +309,8 @@ void isrv_run(
                 int n;
 
                 tv.tv_sec = timeout;
+                if (PEER_COUNT <= 1)
+                        tv.tv_sec = linger_timeout;
                 tv.tv_usec = 0;
                 rd = state->rd;
                 if (WR_COUNT) {
@@ -307,8 +318,9 @@ void isrv_run(
                         wrp = &wr;
                 }
 
-                DPRINTF("run: select(FD_COUNT:%d,timeout:%d)...", FD_COUNT, timeout);
-                n = select(FD_COUNT, &rd, wrp, NULL, timeout ? &tv : NULL);
+                DPRINTF("run: select(FD_COUNT:%d,timeout:%d)...",
+                                FD_COUNT, (int)tv.tv_sec);
+                n = select(FD_COUNT, &rd, wrp, NULL, tv.tv_sec ? &tv : NULL);
                 DPRINTF("run: ...select:%d", n);
 
                 if (n < 0) {
@@ -317,7 +329,7 @@ void isrv_run(
                         continue;
                 }
 
-                if (exit_if_no_clients && n == 0 && PEER_COUNT <= 1)
+                if (n == 0 && linger_timeout && PEER_COUNT <= 1)
                         break;
 
                 if (timeout) {
@@ -334,4 +346,5 @@ void isrv_run(
                 }
         }
         DPRINTF("run: bailout");
+        /* NB: accept socket is not closed. Caller is to decide what to do */
 }
diff --git a/networking/isrv_identd.c b/networking/isrv_identd.c
index b9481f8d3..30f9a7a26 100644
--- a/networking/isrv_identd.c
+++ b/networking/isrv_identd.c
@@ -13,14 +13,6 @@
 
 enum { TIMEOUT = 20 };
 
-/* Why use alarm(TIMEOUT-1)?
- * isrv's internal select() will run with timeout=TIMEOUT.
- * If nothing happens during TIMEOUT-1 seconds (no accept/read),
- * then ALL sessions timed out by now. Instead of closing them one-by-one
- * (isrv calls do_timeout for each 'stale' session),
- * SIGALRM triggered by alarm(TIMEOUT-1) will kill us, terminating them all.
- */
-
 typedef struct identd_buf_t {
         int pos;
         int fd_flag;
@@ -34,8 +26,6 @@ static int new_peer(isrv_state_t *state, int fd)
         int peer;
         identd_buf_t *buf = xzalloc(sizeof(*buf));
 
-        alarm(TIMEOUT - 1);
-
         peer = isrv_register_peer(state, buf);
         if (peer < 0)
                 return 0; /* failure */
@@ -53,11 +43,9 @@ static int do_rd(int fd, void **paramp)
         char *cur, *p;
         int sz;
 
-        alarm(TIMEOUT - 1);
-
         cur = buf->buf + buf->pos;
 
-        fcntl(fd, F_SETFL, buf->fd_flag | O_NONBLOCK);
+        fcntl(fd, F_SETFL, buf->fd_flag);
         sz = safe_read(fd, cur, sizeof(buf->buf) - buf->pos);
 
         if (sz < 0) {
@@ -95,6 +83,8 @@ static void inetd_mode(void)
         identd_buf_t *buf = xzalloc(sizeof(*buf));
         /* We do NOT want nonblocking I/O here! */
         buf->fd_flag = fcntl(0, F_GETFL, 0);
+        do
+                alarm(TIMEOUT);
         while (do_rd(0, (void*)&buf) == 0) /* repeat */;
 }
 
@@ -139,6 +129,7 @@ int fakeidentd_main(int argc, char **argv)
                 xlisten(fd, 5);
         }
 
-        isrv_run(fd, new_peer, do_rd, NULL, do_timeout, TIMEOUT, 1);
+        isrv_run(fd, new_peer, do_rd, /*do_wr:*/ NULL, do_timeout,
+                        TIMEOUT, (opt & OPT_inetdwait) ? TIMEOUT : 0);
         return 0;
 }