[PATCH 3 of 4] SSL: SSL_sendfile(SF_NODISKIO) support

[Maxim Dounin]

# HG changeset patch
# User Maxim Dounin <mdounin at mdounin.ru>
# Date 1636603895 -10800
#      Thu Nov 11 07:11:35 2021 +0300
# Node ID 98d3beb63f32cbb68d1cdcec385614d32129cad0
# Parent  4a954e89b1ae8539bbe08c5afc1d5c9828d82d6f
SSL: SSL_sendfile(SF_NODISKIO) support.

diff --git a/src/event/ngx_event_openssl.c b/src/event/ngx_event_openssl.c
--- a/src/event/ngx_event_openssl.c
+++ b/src/event/ngx_event_openssl.c
@@ -2942,7 +2942,7 @@ ngx_ssl_sendfile(ngx_connection_t *c, ng
 {
 #ifdef BIO_get_ktls_send
 
-    int        sslerr;
+    int        sslerr, flags;
     ssize_t    n;
     ngx_err_t  err;
 
@@ -2954,8 +2954,14 @@ ngx_ssl_sendfile(ngx_connection_t *c, ng
 
     ngx_set_errno(0);
 
+#if (NGX_HAVE_SENDFILE_NODISKIO)
+    flags = (c->busy_count <= 2) ? SF_NODISKIO : 0;
+#else
+    flags = 0;
+#endif
+
     n = SSL_sendfile(c->ssl->connection, file->file->fd, file->file_pos,
-                     size, 0);
+                     size, flags);
 
     ngx_log_debug1(NGX_LOG_DEBUG_EVENT, c->log, 0, "SSL_sendfile: %d", n);
 
@@ -2974,6 +2980,10 @@ ngx_ssl_sendfile(ngx_connection_t *c, ng
             ngx_post_event(c->read, &ngx_posted_events);
         }
 
+#if (NGX_HAVE_SENDFILE_NODISKIO)
+        c->busy_count = 0;
+#endif
+
         c->sent += n;
 
         return n;
@@ -3038,6 +3048,23 @@ ngx_ssl_sendfile(ngx_connection_t *c, ng
             ngx_post_event(c->read, &ngx_posted_events);
         }
 
+#if (NGX_HAVE_SENDFILE_NODISKIO)
+
+        if (ngx_errno == EBUSY) {
+            c->busy_count++;
+
+            ngx_log_debug1(NGX_LOG_DEBUG_EVENT, c->log, 0,
+                           "SSL_sendfile() busy, count:%d", c->busy_count);
+
+            if (c->write->posted) {
+                ngx_delete_posted_event(c->write);
+            }
+
+            ngx_post_event(c->write, &ngx_posted_next_events);
+        }
+
+#endif
+
         c->write->ready = 0;
         return NGX_AGAIN;
     }