[PATCH 1 of 4] Fix socket leak with AIO

[Maxim Dounin]

# HG changeset patch
# User Maxim Dounin <mdounin at mdounin.ru>
# Date 1286631445 -14400
# Node ID 38a938ce08300bb57d0f6c885b1d8c35d602419d
# Parent  94b30aa5d8497cc409579f3253dfa3522c55a28b
Fix socket leak with AIO.

When output buffer size was less than file size we are going to send second
aio post happened if non-first aio operation on the file in question was not
able to complete immediately.

Additionally, on Linux aio event's ready flag wasn't reset after submitting
io request, and as a result there were no "[alert] ... second aio post"
messages.

diff --git a/src/core/ngx_output_chain.c b/src/core/ngx_output_chain.c
--- a/src/core/ngx_output_chain.c
+++ b/src/core/ngx_output_chain.c
@@ -74,18 +74,18 @@ ngx_output_chain(ngx_output_chain_ctx_t 
         }
     }
 
-#if (NGX_HAVE_FILE_AIO)
-    if (ctx->aio) {
-        return NGX_AGAIN;
-    }
-#endif
-
     out = NULL;
     last_out = &out;
     last = NGX_NONE;
 
     for ( ;; ) {
 
+#if (NGX_HAVE_FILE_AIO)
+        if (ctx->aio) {
+            return NGX_AGAIN;
+        }
+#endif
+
         while (ctx->in) {
 
             /*
diff --git a/src/http/ngx_http_copy_filter_module.c b/src/http/ngx_http_copy_filter_module.c
--- a/src/http/ngx_http_copy_filter_module.c
+++ b/src/http/ngx_http_copy_filter_module.c
@@ -211,6 +211,8 @@ ngx_http_copy_aio_handler(ngx_output_cha
 
     r->main->blocked++;
     r->aio = 1;
+
+    ctx->aio = 1;
 }
 
 
diff --git a/src/os/unix/ngx_linux_aio_read.c b/src/os/unix/ngx_linux_aio_read.c
--- a/src/os/unix/ngx_linux_aio_read.c
+++ b/src/os/unix/ngx_linux_aio_read.c
@@ -95,6 +95,10 @@ ngx_file_aio_read(ngx_file_t *file, u_ch
     n = io_submit(ngx_aio_ctx, 1, piocb);
 
     if (n == 1) {
+        ev->active = 1;
+        ev->ready = 0;
+        ev->complete = 0;
+
         return NGX_AGAIN;
     }