Force EOM beyond available range

To ensure that a rogue large message doesn't monopolize the read loop.

diff --git a/x5/khatus.c b/x5/khatus.c
index 5928dfb..2445c1b 100644 (file)
--- a/x5/khatus.c
+++ b/x5/khatus.c
@@ -143,7 +143,7 @@ slot_set_error(Slot *s, char *buf)
 }
 
 enum read_status
-slot_read(Slot *s, struct timespec t, char *buf)
+slot_read(Slot *s, char *buf)
 {
        char c;  /* Character read. */
        int  r;  /* Remaining unused positions in buffer range. */
@@ -174,18 +174,18 @@ slot_read(Slot *s, struct timespec t, char *buf)
                                r = (s->out_pos_hi - s->out_pos_cur) + 1;
                                if (r > 0)
                                        memset(buf + s->out_pos_cur, ' ', r);
-                               s->out_pos_cur = s->out_pos_lo;
-                               s->in_last_read = t;
                                return END_OF_MESSAGE;
                        } else {
                                if (s->out_pos_cur <= s->out_pos_hi)
                                        buf[s->out_pos_cur++] = c;
-                               /* Drop beyond available range. */
-                               /*
-                                * TODO Define max after which we stop reading.
-                                *      To ensure that a rogue large message
-                                *      doesn't trap us here.
-                                */
+                               else
+                                       /*
+                                        * Force EOM beyond available range.
+                                        * To ensure that a rogue large message
+                                        * doesn't trap us here needlessly
+                                        * long.
+                                        */
+                                       return END_OF_MESSAGE;
                        }
                        break;
                default:
@@ -277,7 +277,7 @@ slots_read(Config *cfg, struct timespec *ti, char *buf)
                                continue;
                        if (FD_ISSET(s->in_fd, &fds)) {
                                khlib_debug("reading: %s\n", s->in_fifo);
-                               switch (slot_read(s, t, buf)) {
+                               switch (slot_read(s, buf)) {
                                /*
                                 * ### MESSAGE LOSS ###
                                 * is introduced by closing at EOM in addition
@@ -309,7 +309,9 @@ slots_read(Config *cfg, struct timespec *ti, char *buf)
                                case END_OF_FILE:
                                case FAILURE:
                                        close(s->in_fd);
-                                       s->in_fd = -1;
+                                       s->in_fd        = -1;
+                                       s->in_last_read = t;
+                                       s->out_pos_cur  = s->out_pos_lo;
                                        ready--;
                                        break;
                                case RETRY: