From 5c6ef9d0ff79db64bac36a22b43bad713c223297 Mon Sep 17 00:00:00 2001
From: Ian Jackson <ian@liberator.(none)>
Date: Sun, 11 Apr 2010 13:07:09 +0100
Subject: [PATCH] Abolish SEPARATED2 and DROPPING2; recordeofness in ipf->fd

---
 backends/innduct.c | 57 ++++++++++++++++++++++++++++------------------
 1 file changed, 35 insertions(+), 22 deletions(-)

diff --git a/backends/innduct.c b/backends/innduct.c
index f3be2b7..6a6e51a 100644
--- a/backends/innduct.c
+++ b/backends/innduct.c
@@ -272,10 +272,8 @@ typedef enum {
   sm_NORMAL,
   sm_FLUSHING,
   sm_FLUSHFAIL,
-  sm_SEPARATED1,
-  sm_SEPARATED2, /* must follow SEPARATED2 - see feedfile_eof */
-  sm_DROPPING1,
-  sm_DROPPING2, /* must follow DROPPING1 - see feedfile_eof */
+  sm_SEPARATED,
+  sm_DROPPING,
 } StateMachineState;
 
 struct Conn {
@@ -1050,11 +1048,13 @@ static void feedfile_eof(InputFile *ipf) {
   assert(ipf != main_input_file); /* promised by tailing_try_read */
   assert(ipf == old_input_file);
 
-  if (sms==sm_SEPARATED1) SMS(SEPARATED2, 0, "eof on old feed file");
-  else if (sms==sm_DROPPING1) SMS(DROPPING2, 0, "eof on dead feed file");
-  else abort();
-  
   inputfile_tailing_stop(ipf);
+  assert(ipf->fd >= 0);
+  if (close(ipf->fd)) sysdie("could not close input file %s", ipf->path);
+  ipf->fd= -1;
+
+  assert(sms==sm_SEPARATED || sms==sm_DROPPING);
+  
   if (main_input_file)
     inputfile_tailing_start(main_input_file);
 }
@@ -1085,7 +1085,8 @@ static void close_input_file(InputFile *ipf) {
   assert(!ipf->rd); /* must have had inputfile_tailing_stop */
   assert(!ipf->inprogress); /* no dangling pointers pointing here */
 
-  if (close(ipf->fd)) sysdie("could not close input file %s", ipf->path);
+  if (ipf->fd>=0)
+    if (close(ipf->fd)) sysdie("could not close input file %s", ipf->path);
   free(ipf);
 }
 
@@ -1203,8 +1204,17 @@ static ssize_t tailing_try_read(struct oop_readable *rable, void *buffer,
       return r;
     }
     if (!r) {
-      if (ipf==main_input_file) { errno=EAGAIN; return -1; }
-      assert(sms==sm_SEPARATED1 || sms==sm_DROPPING1);
+      if (ipf==main_input_file) {
+	errno=EAGAIN;
+	return -1;
+      } else if (ipf==old_input_file) {
+	assert(ipf->fd>=0);
+	assert(sms==sm_SEPARATED || sms==sm_DROPPING);
+      } else if (ipf==backlog_input_file) {
+	assert(ipf->fd>=0);
+      } else {
+	abort();
+      }
     }
     return r;
   }
@@ -1387,7 +1397,8 @@ static void inputfile_tailing_stop(InputFile *ipf) {
      |          | open F                       \
      |          V                               V
      |     =============                     ============
-     |      SEPARATED1                        DROPPING1
+     |      SEPARATED/                        DROPPING/
+     |      old->fd>=0                        old->fd>=0
      |     [Separated]                       [Dropping]
      |      main F idle                       main none
      |      old  D tail                       old  D tail
@@ -1395,12 +1406,13 @@ static void inputfile_tailing_stop(InputFile *ipf) {
      |          |                                 |
      ^          | EOF ON D                        | EOF ON D
      |          V                                 V
-     |     =============                     ============
-     |      SEPARATED2                        DROPPING2
+     |     ===============                   ===============
+     |      SEPARATED/                        DROPPING/
+     |      old->fd==-1                       old->fd==-1
      |     [Finishing]                       [Dropping]
      |      main F tail	                      main none
-     |      old  D idle                       old  D idle
-     |     =============       	             ============
+     |      old  D closed                     old  D closed
+     |     ===============     	             ===============
      |          |		               	 |
      |          | ALL D PROCESSED                | ALL D PROCESSED
      |          V install defer as backlog       V install defer as backlog
@@ -1539,7 +1551,7 @@ static void statemc_init(void) {
       spawn_inndcomm_flush(); /* => Flushing, sets sms to sm_FLUSHING */
     } else {
       /* F!=D => Separated */
-      SMS(SEPARATED1, 0, "found both old and current feed files");
+      SMS(SEPARATED, 0, "found both old and current feed files");
       startup_set_input_file(file_d);
     }
   } else { /*!file_d*/
@@ -1583,8 +1595,9 @@ static void *statemc_check_oldinput_done(oop_source *lp,
 					 struct timeval now, void *u) {
   struct stat stab;
 
-  int done= (sms==sm_SEPARATED2 || sms==sm_DROPPING2)
-         && old_input_file->inprogress;
+  int done= (sms==sm_SEPARATED || sms==sm_DROPPING)
+         && old_input_file->fd==-1
+         && !old_input_file->inprogress;
   if (!done) return;
 
   r= fstat(fileno(defer), &stab);
@@ -1606,7 +1619,7 @@ static void *statemc_check_oldinput_done(oop_source *lp,
   if (unlink(path_duct))
     sysdie("could not unlink old duct file %s", path_duct);
 
-  if (sms==sm_DROPPING2) {
+  if (sms==sm_DROPPING) {
     notice("feed dropped and our work is complete"
 	   " (but check for backlog files)");
     exit(0);
@@ -1654,7 +1667,7 @@ static void *inndcomm_event(oop_source *lp, int fd, oop_event e, void *u) {
       warn("feed has been dropped by innd, finishing up");
       old_input_file= main_input_file;
       main_input_file= 0;
-      SMS(DROPPING1, 0, "dropped by innd");
+      SMS(DROPPING, 0, "dropped by innd");
       return OOP_CONTINUE;
 
     case 0:
@@ -1662,7 +1675,7 @@ static void *inndcomm_event(oop_source *lp, int fd, oop_event e, void *u) {
       main_input_file= open_input_file(feedfile);
       if (!main_input_file)
 	die("flush succeeded but feedfile %s does not exist!", feedfile);
-      SMS(SEPARATED1, 0, "feed file missing");
+      SMS(SEPARATED, 0, "feed file missing");
       return OOP_CONTINUE;
 
     default:
-- 
2.30.2