chiark / gitweb /
comment for dealing with wedge problems
[inn-innduct.git] / backends / innduct.c
index f1f8fd4a9ae6edb0ab54345bd6e45b5dac7c0568..18ce508c2ce93672d57e17411ee786c78a276f02 100644 (file)
@@ -1,12 +1,28 @@
 /*
- * todo
- *  - manpage: document control master stuff
- *  - admin-initiated flush
- *
  * debugging rune:
  *  build-lfs/backends/innduct --connection-timeout=30 --no-daemon -C ../inn.conf -f `pwd`/fee sit localhost
  */
 
+/*--
+flow control notes
+to ensure articles go away eventually
+separate queue for each input file
+  queue expiry
+    every period, check head of backlog queue for expiry with SMretrieve
+      if too old: discard, and check next article
+    also check every backlog article as we read it
+  flush expiry
+    after too long in SEPARATED/DROPPING ie Separated/Finishing/Dropping
+    one-off: eat queued articles from flushing and write them to defer
+    one-off: connfail all connections which have any articles from flushing
+    newly read articles from flushing go straight to defer
+    this should take care of it and get us out of this state
+to avoid filling up ram needlessly
+  input control
+    limit number of queued articles for each ipf
+    pause/resume inputfile tailing
+--*/
+
 /*
  * Newsfeeds file entries should look like this:
  *     host.name.of.site[/exclude,exclude,...]\
@@ -297,6 +313,7 @@ static void statemc_setstate(StateMachineState newsms, int periods,
 
 static void statemc_start_flush(const char *why); /* Normal => Flushing */
 static void spawn_inndcomm_flush(const char *why); /* Moved => Flushing */
+static int trigger_flush_ok(void); /* => Flushing,FLUSHING, ret 1; or ret 0 */
 
 static void article_done(Conn *conn, Article *art, int whichcount);
 
@@ -408,13 +425,12 @@ typedef enum {
 #define CONNIOVS 128
 
 typedef enum {
-  xk_Malloc, xk_Const, xk_Artdata
+  xk_Const, xk_Artdata
 } XmitKind;
 
 struct XmitDetails {
   XmitKind kind;
   union {
-    char *malloc_tofree;
     ARTHANDLE *sm_art;
   } info;
 };
@@ -499,7 +515,7 @@ static pid_t self_pid;
 
 /* statemc_init initialises */
 static StateMachineState sms;
-static int sm_period_counter;
+static int until_flush;
 static InputFile *main_input_file, *flushing_input_file, *backlog_input_file;
 static FILE *defer;
 
@@ -816,13 +832,14 @@ CCMD(help) {
   const ControlCommand *ccmd;
   for (ccmd=control_commands; ccmd->cmd; ccmd++)
     fprintf(cc->out, " %s\n", ccmd->cmd);
+  fputs("NB: permissible arguments are not shown above."
+       "  Not all commands listed are safe.  See innduct(8).\n", cc->out);
 }
 
-CCMD(period) { period(); }
-CCMD(setintarg) { *(int*)c->xdata= atoi(arg); }
-CCMD(setint) { *(int*)c->xdata= c->xval; }
-CCMD(setint_period) { *(int*)c->xdata= c->xval; period(); }
-CCMD(dump);
+CCMD(flush) {
+  int ok= trigger_flush_ok();
+  if (!ok) fprintf(cc->out,"already flushing (state is %s)\n", sms_names[sms]);
+}
 
 CCMD(stop) {
   preterminate();
@@ -831,19 +848,29 @@ CCMD(stop) {
   abort();
 }
 
+CCMD(dump);
+
+/* messing with our head: */
+CCMD(period) { period(); }
+CCMD(setintarg) { *(int*)c->xdata= atoi(arg); }
+CCMD(setint) { *(int*)c->xdata= c->xval; }
+CCMD(setint_period) { *(int*)c->xdata= c->xval; period(); }
+
 static const ControlCommand control_commands[]= {
   { "h",             ccmd_help      },
-  { "p",             ccmd_period    },
+  { "flush",         ccmd_flush     },
   { "stop",          ccmd_stop      },
   { "dump q",        ccmd_dump, 0,0 },
   { "dump a",        ccmd_dump, 0,1 },
 
+  { "p",             ccmd_period    },
+
 #define POKES(cmd,func)                                                        \
-  { cmd "sm",        func,           &sm_period_counter,       1 },    \
+  { cmd "flush",     func,           &until_flush,             1 },    \
   { cmd "conn",      func,           &until_connect,           0 },    \
   { cmd "blscan",    func,           &until_backlog_nextscan,  0 },
-POKES("prod ", ccmd_setint_period)
 POKES("next ", ccmd_setint)
+POKES("prod ", ccmd_setint_period)
 
   { "pretend flush", ccmd_setintarg, &simulate_flush             },
   { "wedge blscan",  ccmd_setint,    &until_backlog_nextscan, -1 },
@@ -1502,7 +1529,6 @@ static void xmit_artbody(Conn *conn, ARTHANDLE *ah /* consumed */) {
 
 static void xmit_free(XmitDetails *d) {
   switch (d->kind) {
-  case xk_Malloc:  free(d->info.malloc_tofree);   break;
   case xk_Artdata: SMfreearticle(d->info.sm_art); break;
   case xk_Const:                                  break;
   default: abort();
@@ -1966,7 +1992,7 @@ static void *feedfile_got_article(oop_source *lp, oop_read *rd,
   ipf->readcount_ok++;
 
   art= xmalloc(sizeof(*art) - 1 + midlen + 1);
-  memset(art,0,sizeof(art));
+  memset(art,0,sizeof(*art));
   art->state= art_Unchecked;
   art->midlen= midlen;
   art->ipf= ipf;  ipf->inprogress++;
@@ -2271,7 +2297,7 @@ static void inputfile_reading_stop(InputFile *ipf) {
      |      flsh->rd!=0       |     |              flsh->rd!=0
      |     [Separated]        |     |             [Dropping]
      |      main F idle       |     |              main none
-     |      old D tail        |     |              old D tail
+     |      flsh D tail       |     |              flsh D tail
      |     =============      |     |             ============
      |          |             |     | install       |
      ^          | EOF ON D    |     |  defer        | EOF ON D
@@ -2281,7 +2307,7 @@ static void inputfile_reading_stop(InputFile *ipf) {
      |      flsh->rd==0       |     V              flsh->rd==0
      |     [Finishing]        |     |             [Dropping]
      |      main F tail              |     `.             main none
-     |      old D closed      |       `.           old D closed
+     |      flsh D closed     |       `.           flsh D closed
      |     ===============    V                `.        ===============
      |          |                        `.          |
      |          | ALL D PROCESSED           `.        | ALL D PROCESSED
@@ -2294,7 +2320,7 @@ static void inputfile_reading_stop(InputFile *ipf) {
                                                 DROPPED
                                                [Dropped]
                                                 main none
-                                                old none
+                                                flsh none
                                                 some backlog
                                                ==============
                                                      |
@@ -2410,6 +2436,9 @@ static void statemc_init(void) {
     if (file_d) {
       debug("startup: F!=D => Separated");
       startup_set_input_file(file_d);
+      flushing_input_file= main_input_file;
+      main_input_file= open_input_file(feedfile);
+      if (!main_input_file) die("feedfile vanished during startup");
       SMS(SEPARATED, 0, "found both old and current feed files");
     } else {
       debug("startup: F exists, D ENOENT => Normal");
@@ -2428,7 +2457,7 @@ static void statemc_start_flush(const char *why) { /* Normal => Flushing */
        why,
        (unsigned long)(main_input_file ? main_input_file->offset : 0),
        (unsigned long)target_max_feedfile_size,
-       sm_period_counter);
+       until_flush);
 
   int r= link(feedfile, path_flushing);
   if (r) sysfatal("link feedfile %s to flushing file %s",
@@ -2441,24 +2470,29 @@ static void statemc_start_flush(const char *why) { /* Normal => Flushing */
   spawn_inndcomm_flush(why); /* => Flushing FLUSHING */
 }
 
-static void statemc_period_poll(void) {
-  if (!sm_period_counter) return;
-  sm_period_counter--;
-  assert(sm_period_counter>=0);
-
-  if (sm_period_counter) return;
+static int trigger_flush_ok(void) { /* => Flushing,FLUSHING, ret 1; or ret 0 */
   switch (sms) {
   case sm_NORMAL:
     statemc_start_flush("periodic"); /* Normal => Flushing; => FLUSHING */
-    break;
+    return 1;
   case sm_FLUSHFAILED:
     spawn_inndcomm_flush("retry"); /* Moved => Flushing; => FLUSHING */
-    break;
+    return 1;
   default:
-    abort();
+    return 0;
   }
 }
 
+static void statemc_period_poll(void) {
+  if (!until_flush) return;
+  until_flush--;
+  assert(until_flush>=0);
+
+  if (until_flush) return;
+  int ok= trigger_flush_ok();
+  assert(ok);
+}
+
 static int inputfile_is_done(InputFile *ipf) {
   if (!ipf) return 0;
   if (ipf->inprogress) return 0; /* new article in the meantime */
@@ -2564,7 +2598,7 @@ static void queue_check_input_done(void) {
 static void statemc_setstate(StateMachineState newsms, int periods,
                             const char *forlog, const char *why) {
   sms= newsms;
-  sm_period_counter= periods;
+  until_flush= periods;
 
   const char *xtra= "";
   switch (sms) {
@@ -2782,7 +2816,7 @@ static void search_backlog_file(void) {
 static void preterminate(void) {
   if (in_child) return;
   notice_processed(main_input_file,0,"feedfile","");
-  notice_processed(flushing_input_file,0,"flushing file","");
+  notice_processed(flushing_input_file,0,"flushing","");
   if (backlog_input_file)
     notice_processed(backlog_input_file,0, "backlog file ",
                     backlog_input_file->path);
@@ -3065,7 +3099,7 @@ static void period(void) {
        " input_files main:%s flushing:%s backlog:%s"
        " children connecting=%ld inndcomm=%ld"
        ,
-       sms_names[sms], sm_period_counter,
+       sms_names[sms], until_flush,
          conns.count, queue.count, until_connect,
        dipf_main, dipf_flushing, dipf_backlog,
        (long)connecting_child, (long)inndcomm_child
@@ -3136,7 +3170,7 @@ CCMD(dump) {
 
   fprintf(f,"general");
   DUMPV("%s", sms_names,[sms]);
-  DUMPV("%d", ,sm_period_counter);
+  DUMPV("%d", ,until_flush);
   DUMPV("%ld", (long),self_pid);
   DUMPV("%p", , defer);
   DUMPV("%d", , until_connect);
@@ -3183,16 +3217,8 @@ CCMD(dump) {
       char *dinfo;
       long diff;
       switch (xd->kind) {
-      case xk_Malloc:
-       diff= xd->info.malloc_tofree - (char*)iv->iov_base;
-       dinfo= xasprintf("M%5ld", diff);
-       break;
-      case xk_Const:
-       dinfo= xasprintf("Const");
-       break;
-      case xk_Artdata:
-       dinfo= xasprintf("A%p", xd->info.sm_art);
-       break;
+      case xk_Const:    dinfo= xasprintf("Const");                 break;
+      case xk_Artdata:  dinfo= xasprintf("A%p", xd->info.sm_art);  break;
       default:
        abort();
       }