[nginx] Resolver: fixed debug event logging.

[Ruslan Ermilov]

details:   http://hg.nginx.org/nginx/rev/5004210e8c78
branches:  
changeset: 5921:5004210e8c78
user:      Ruslan Ermilov <ru at nginx.com>
date:      Thu Nov 20 15:24:42 2014 +0300
description:
Resolver: fixed debug event logging.

In 954867a2f0a6, we switched to using resolver node as the timer event data.
This broke debug event logging.

Replaced now unused ngx_resolver_ctx_t.ident with ngx_resolver_node_t.ident
so that ngx_event_ident() extracts something sensible when accessing
ngx_resolver_node_t as ngx_connection_t.

diffstat:

 src/core/ngx_resolver.c |  25 +++++++++++++++----------
 src/core/ngx_resolver.h |  15 ++++++++-------
 2 files changed, 23 insertions(+), 17 deletions(-)

diffs (132 lines):

diff -r 7420068c4d4b -r 5004210e8c78 src/core/ngx_resolver.c
--- a/src/core/ngx_resolver.c	Thu Nov 20 15:24:40 2014 +0300
+++ b/src/core/ngx_resolver.c	Thu Nov 20 15:24:42 2014 +0300
@@ -48,6 +48,11 @@ typedef struct {
 } ngx_resolver_an_t;
 
 
+#define ngx_resolver_node(n)                                                 \
+    (ngx_resolver_node_t *)                                                  \
+        ((u_char *) (n) - offsetof(ngx_resolver_node_t, node))
+
+
 ngx_int_t ngx_udp_connect(ngx_udp_connection_t *uc);
 
 
@@ -288,7 +293,7 @@ ngx_resolver_cleanup_tree(ngx_resolver_t
 
     while (tree->root != tree->sentinel) {
 
-        rn = (ngx_resolver_node_t *) ngx_rbtree_min(tree->root, tree->sentinel);
+        rn = ngx_resolver_node(ngx_rbtree_min(tree->root, tree->sentinel));
 
         ngx_queue_remove(&rn->queue);
 
@@ -666,7 +671,7 @@ ngx_resolve_name_locked(ngx_resolver_t *
         ctx->event->handler = ngx_resolver_timeout_handler;
         ctx->event->data = rn;
         ctx->event->log = r->log;
-        ctx->ident = -1;
+        rn->ident = -1;
 
         ngx_add_timer(ctx->event, ctx->timeout);
     }
@@ -859,7 +864,7 @@ ngx_resolve_addr(ngx_resolver_ctx_t *ctx
     ctx->event->handler = ngx_resolver_timeout_handler;
     ctx->event->data = rn;
     ctx->event->log = r->log;
-    ctx->ident = -1;
+    rn->ident = -1;
 
     ngx_add_timer(ctx->event, ctx->timeout);
 
@@ -2290,7 +2295,7 @@ ngx_resolver_lookup_name(ngx_resolver_t 
 
         /* hash == node->key */
 
-        rn = (ngx_resolver_node_t *) node;
+        rn = ngx_resolver_node(node);
 
         rc = ngx_memn2cmp(name->data, rn->name, name->len, rn->nlen);
 
@@ -2329,7 +2334,7 @@ ngx_resolver_lookup_addr(ngx_resolver_t 
 
         /* addr == node->key */
 
-        return (ngx_resolver_node_t *) node;
+        return ngx_resolver_node(node);
     }
 
     /* not found */
@@ -2365,7 +2370,7 @@ ngx_resolver_lookup_addr6(ngx_resolver_t
 
         /* hash == node->key */
 
-        rn = (ngx_resolver_node_t *) node;
+        rn = ngx_resolver_node(node);
 
         rc = ngx_memcmp(addr, &rn->addr6, 16);
 
@@ -2403,8 +2408,8 @@ ngx_resolver_rbtree_insert_value(ngx_rbt
 
         } else { /* node->key == temp->key */
 
-            rn = (ngx_resolver_node_t *) node;
-            rn_temp = (ngx_resolver_node_t *) temp;
+            rn = ngx_resolver_node(node);
+            rn_temp = ngx_resolver_node(temp);
 
             p = (ngx_memn2cmp(rn->name, rn_temp->name, rn->nlen, rn_temp->nlen)
                  < 0) ? &temp->left : &temp->right;
@@ -2446,8 +2451,8 @@ ngx_resolver_rbtree_insert_addr6_value(n
 
         } else { /* node->key == temp->key */
 
-            rn = (ngx_resolver_node_t *) node;
-            rn_temp = (ngx_resolver_node_t *) temp;
+            rn = ngx_resolver_node(node);
+            rn_temp = ngx_resolver_node(temp);
 
             p = (ngx_memcmp(&rn->addr6, &rn_temp->addr6, 16)
                  < 0) ? &temp->left : &temp->right;
diff -r 7420068c4d4b -r 5004210e8c78 src/core/ngx_resolver.h
--- a/src/core/ngx_resolver.h	Thu Nov 20 15:24:40 2014 +0300
+++ b/src/core/ngx_resolver.h	Thu Nov 20 15:24:42 2014 +0300
@@ -51,11 +51,15 @@ typedef void (*ngx_resolver_handler_pt)(
 
 
 typedef struct {
-    ngx_rbtree_node_t         node;
+    /* PTR: resolved name, A: name to resolve */
+    u_char                   *name;
+
     ngx_queue_t               queue;
 
-    /* PTR: resolved name, A: name to resolve */
-    u_char                   *name;
+    /* event ident must be after 3 pointers as in ngx_connection_t */
+    ngx_int_t                 ident;
+
+    ngx_rbtree_node_t         node;
 
 #if (NGX_HAVE_INET6)
     /* PTR: IPv6 address to resolve (IPv4 address is in rbtree node key) */
@@ -103,7 +107,7 @@ typedef struct {
     void                     *dummy;
     ngx_log_t                *log;
 
-    /* ident must be after 3 pointers */
+    /* event ident must be after 3 pointers as in ngx_connection_t */
     ngx_int_t                 ident;
 
     /* simple round robin DNS peers balancer */
@@ -143,9 +147,6 @@ struct ngx_resolver_ctx_s {
     ngx_resolver_t           *resolver;
     ngx_udp_connection_t     *udp_connection;
 
-    /* ident must be after 3 pointers */
-    ngx_int_t                 ident;
-
     ngx_int_t                 state;
     ngx_str_t                 name;