From: Ian Jackson <ian@chiark.greenend.org.uk>
Date: Tue, 1 Jun 2010 15:21:03 +0000 (+0100)
Subject: Always call cancel_time before on_time to make sure we have only one queued up
X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ian/git?p=innduct.git;a=commitdiff_plain;h=bf7885f2a107fcd4c58c144a1658a3acc8311f3a;hp=ff034fbd099c2ad74cba31e5beb9f1f54a80fc29

Always call cancel_time before on_time to make sure we have only one queued up
---

diff --git a/infile.c b/infile.c
index 3c93d1f..32c4497 100644
--- a/infile.c
+++ b/infile.c
@@ -178,6 +178,8 @@ static void *feedfile_got_article(oop_source *lp, oop_read *rd,
 
 /*========== tailing input file ==========*/
 
+static void tailing_rable_on_time(InputFile *ipf);
+
 static void *tailing_rable_call_time(oop_source *lp, struct timeval tv,
 				     void *user) {
   /* lifetime of ipf here is OK because destruction will cause
@@ -190,13 +192,20 @@ static void *tailing_rable_call_time(oop_source *lp, struct timeval tv,
   /* we just keep calling readable until our caller (oop_rd)
    * has called try_read, and try_read has found EOF so given EAGAIN */
   dbg("**TRACT** ipf=%p reschedule",ipf);
-  loop->on_time(loop, OOP_TIME_NOW, tailing_rable_call_time, ipf);
+  tailing_rable_on_time(ipf);
 
-  assert(ipf->readable_callback):
+  assert(ipf->readable_callback);
   return ipf->readable_callback(loop, &ipf->readable,
 				ipf->readable_callback_user);
 }
 
+static void tailing_rable_on_time(InputFile *ipf) {
+  loop->cancel_time(loop, OOP_TIME_NOW, tailing_rable_call_time, ipf);
+  loop->on_time(loop, OOP_TIME_NOW, tailing_rable_call_time, ipf);
+  /* on_time is not idempotent - it counts.   So we need this to make
+   * sure we only have one outstanding, as otherwise our cancel doesn't work */
+}
+
 static void tailing_on_cancel(struct oop_readable *rable) {
   InputFile *ipf= (void*)rable;
   dbg("**TOR** ipf=%p on_cancel",ipf);
@@ -213,7 +222,7 @@ void tailing_make_readable(InputFile *ipf) {
   if (!ipf || !ipf->readable_callback) /* so callers can be naive */
     return;
   ipf->fake_readable= 1;
-  loop->on_time(loop, OOP_TIME_NOW, tailing_rable_call_time, ipf);
+  tailing_rable_on_time(ipf);
 }
 
 static int tailing_on_readable(struct oop_readable *rable,