[PATCH] Improved code readablity of ngx_cache_manager_process_cycle.

[Ruslan Ermilov]

On Thu, Apr 05, 2018 at 12:37:19PM +0800, Zexuan Luo wrote:
> # HG changeset patch
> # User spacewander <spacewanderlzx at gmail.com>
> # Date 1522902794 -28800
> #      Thu Apr 05 12:33:14 2018 +0800
> # Branch ident
> # Node ID e0834ca20c9c68c4f0728f85efb3651732134ee2
> # Parent  d4cc2edb4ff8391d0c7419e91e6fcc988c510654
> Improved code readablity of ngx_cache_manager_process_cycle.
> 
> diff -r d4cc2edb4ff8 -r e0834ca20c9c src/os/unix/ngx_process_cycle.c
> --- a/src/os/unix/ngx_process_cycle.c   Tue Apr 03 17:38:10 2018 +0300
> +++ b/src/os/unix/ngx_process_cycle.c   Thu Apr 05 12:33:14 2018 +0800
> @@ -1128,7 +1128,7 @@
>  {
>      ngx_cache_manager_ctx_t *ctx = data;
> 
> -    void         *ident[4];
> +   u_char            ident[offsetof(ngx_connection_t, fd) +
> sizeof(ngx_socket_t)];
>      ngx_event_t   ev;
> 
>      /*
> @@ -1148,7 +1148,7 @@
>      ev.handler = ctx->handler;
>      ev.data = ident;
>      ev.log = cycle->log;
> -    ident[3] = (void *) -1;
> +   *(ngx_socket_t *)(ident + offsetof(ngx_connection_t, fd)) = -1;
> 
>      ngx_use_accept_mutex = 0;

How's this instead?  A similar comment also exists in ngx_resolver.h.

diff --git a/src/os/unix/ngx_process_cycle.c b/src/os/unix/ngx_process_cycle.c
--- a/src/os/unix/ngx_process_cycle.c
+++ b/src/os/unix/ngx_process_cycle.c
@@ -1128,8 +1128,10 @@ ngx_cache_manager_process_cycle(ngx_cycl
 {
     ngx_cache_manager_ctx_t *ctx = data;
 
-    void         *ident[4];
-    ngx_event_t   ev;
+    /* event ident must be after 3 pointers as in ngx_connection_t */
+    void              *ident[4];
+    ngx_event_t        ev;
+    ngx_connection_t  *c;
 
     /*
      * Set correct process type since closing listening Unix domain socket
@@ -1144,11 +1146,13 @@ ngx_cache_manager_process_cycle(ngx_cycl
 
     ngx_worker_process_init(cycle, -1);
 
+    c = (ngx_connection_t *) ident;
+    c->fd = (ngx_socket_t) -1;
+
     ngx_memzero(&ev, sizeof(ngx_event_t));
     ev.handler = ctx->handler;
-    ev.data = ident;
+    ev.data = c;
     ev.log = cycle->log;
-    ident[3] = (void *) -1;
 
     ngx_use_accept_mutex = 0;