more fixes for IP requests which remain pending for a long time.

Can't release them out from under the read handler.  Now lock them
between writing and reading.  Also need to change the key for entries
which have been preempted.

diff --git a/src/ipcache.cc b/src/ipcache.cc
index 293f95e2a25cb9ec83687f10f158eaebfc0e7e6f..75cd0afd804fdca8c5032a0e66cb6fc5090690df 100644 (file)
--- a/src/ipcache.cc
+++ b/src/ipcache.cc
@@ -1,5 +1,5 @@
 /*
- * $Id: ipcache.cc,v 1.94 1997/01/03 22:45:49 wessels Exp $
+ * $Id: ipcache.cc,v 1.95 1997/01/13 20:44:45 wessels Exp $
  *
  * DEBUG: section 14    IP Cache
  * AUTHOR: Harvest Derived
@@ -159,6 +159,7 @@ static void ipcacheStatPrint _PARAMS((ipcache_entry *, StoreEntry *));
 static void ipcacheUnlockEntry _PARAMS((ipcache_entry *));
 static void ipcacheLockEntry _PARAMS((ipcache_entry *));
 static void ipcacheNudgeQueue _PARAMS((void));
+static void ipcacheChangeKey _PARAMS((ipcache_entry * i));
 
 static ipcache_addrs static_addrs;
 static HashID ip_table = 0;
@@ -608,6 +609,7 @@ ipcache_dnsHandleRead(int fd, dnsserver_t * dnsData)
            ipcache_call_pending(i);
        }
     }
+    ipcacheUnlockEntry(i);     /* unlock from IP_DISPATCHED */
     if (dnsData->offset == 0) {
        dnsData->data = NULL;
        dnsData->flags &= ~DNS_FLAG_BUSY;
@@ -685,8 +687,9 @@ ipcache_nbgethostbyname(const char *name, int fd, IPH handler, void *handlerData
        IpcacheStats.pending_hits++;
        ipcacheAddPending(i, fd, handler, handlerData);
        if (squid_curtime - i->expires > 60) {
+           ipcacheChangeKey(i);
            i->status = IP_NEGATIVE_CACHED;
-           ipcache_call_pending(i);    /* will also release it */
+           ipcache_call_pending(i);
        }
        return;
     } else {
@@ -737,6 +740,7 @@ ipcache_dnsDispatch(dnsserver_t * dns, ipcache_entry * i)
     dns->dispatch_time = current_time;
     DnsStats.requests++;
     DnsStats.hist[dns->id - 1]++;
+    ipcacheLockEntry(i);       /* lock while IP_DISPATCHED */
 }
 
 
@@ -1063,3 +1067,27 @@ ipcacheFreeMemory(void)
     xfree(list);
     hashFreeMemory(ip_table);
 }
+
+static void
+ipcacheChangeKey(ipcache_entry * i)
+{
+    static int index = 0;
+    LOCAL_ARRAY(char, new_key, 256);
+    hash_link *table_entry = hash_lookup(ip_table, i->name);
+    if (table_entry == NULL) {
+       debug(14, 0, "ipcacheChangeKey: Could not find key '%s'\n", i->name);
+       return;
+    }
+    if (i != (ipcache_entry *) table_entry) {
+       debug_trap("ipcacheChangeKey: i != table_entry!");
+       return;
+    }
+    if (hash_remove_link(ip_table, table_entry)) {
+       debug_trap("ipcacheChangeKey: hash_remove_link() failed\n");
+       return;
+    }
+    sprintf(new_key, "%d/%128.128s", ++index, i->name);
+    safe_free(i->name);
+    i->name = xstrdup(new_key);
+    ipcache_add_to_hash(i);
+}