diff --git a/src/core/nginx.c b/src/core/nginx.c
index a5fbccd40..80a5d18ae 100644
--- a/src/core/nginx.c
+++ b/src/core/nginx.c
@@ -859,14 +859,11 @@ ngx_process_options(ngx_cycle_t *cycle)
 #else
 
 #ifdef NGX_CONF_PREFIX
-        cycle->conf_prefix.len = sizeof(NGX_CONF_PREFIX) - 1;
-        cycle->conf_prefix.data = (u_char *) NGX_CONF_PREFIX;
+        ngx_str_set(&cycle->conf_prefix, NGX_CONF_PREFIX);
 #else
-        cycle->conf_prefix.len = sizeof(NGX_PREFIX) - 1;
-        cycle->conf_prefix.data = (u_char *) NGX_PREFIX;
+        ngx_str_set(&cycle->conf_prefix, NGX_PREFIX);
 #endif
-        cycle->prefix.len = sizeof(NGX_PREFIX) - 1;
-        cycle->prefix.data = (u_char *) NGX_PREFIX;
+        ngx_str_set(&cycle->prefix, NGX_PREFIX);
 
 #endif
     }
@@ -876,8 +873,7 @@ ngx_process_options(ngx_cycle_t *cycle)
         cycle->conf_file.data = ngx_conf_file;
 
     } else {
-        cycle->conf_file.len = sizeof(NGX_CONF_PATH) - 1;
-        cycle->conf_file.data = (u_char *) NGX_CONF_PATH;
+        ngx_str_set(&cycle->conf_file, NGX_CONF_PATH);
     }
 
     if (ngx_conf_full_name(cycle, &cycle->conf_file, 0) != NGX_OK) {
@@ -993,8 +989,7 @@ ngx_core_module_init_conf(ngx_cycle_t *cycle, void *conf)
 
 
     if (ccf->pid.len == 0) {
-        ccf->pid.len = sizeof(NGX_PID_PATH) - 1;
-        ccf->pid.data = (u_char *) NGX_PID_PATH;
+        ngx_str_set(&ccf->pid, NGX_PID_PATH);
     }
 
     if (ngx_conf_full_name(cycle, &ccf->pid, 0) != NGX_OK) {
@@ -1042,8 +1037,7 @@ ngx_core_module_init_conf(ngx_cycle_t *cycle, void *conf)
 
 
     if (ccf->lock_file.len == 0) {
-        ccf->lock_file.len = sizeof(NGX_LOCK_PATH) - 1;
-        ccf->lock_file.data = (u_char *) NGX_LOCK_PATH;
+        ngx_str_set(&ccf->lock_file, NGX_LOCK_PATH);
     }
 
     if (ngx_conf_full_name(cycle, &ccf->lock_file, 0) != NGX_OK) {
diff --git a/src/core/ngx_conf_file.c b/src/core/ngx_conf_file.c
index 6d5f510ee..20d9af9e4 100644
--- a/src/core/ngx_conf_file.c
+++ b/src/core/ngx_conf_file.c
@@ -903,8 +903,7 @@ ngx_conf_open_file(ngx_cycle_t *cycle, ngx_str_t *name)
     ngx_open_file_t  *file;
 
 #if (NGX_SUPPRESS_WARN)
-    full.len = 0;
-    full.data = NULL;
+    ngx_str_null(&full);
 #endif
 
     if (name->len) {
diff --git a/src/core/ngx_file.c b/src/core/ngx_file.c
index b5160f3ea..ed6d8426c 100644
--- a/src/core/ngx_file.c
+++ b/src/core/ngx_file.c
@@ -825,8 +825,7 @@ ngx_walk_tree(ngx_tree_ctx_t *ctx, ngx_str_t *tree)
     ngx_str_t   file, buf;
     ngx_dir_t   dir;
 
-    buf.len = 0;
-    buf.data = NULL;
+    ngx_str_null(&buf);
 
     ngx_log_debug1(NGX_LOG_DEBUG_CORE, ctx->log, 0,
                    "walk tree \"%V\"", tree);
diff --git a/src/core/ngx_log.c b/src/core/ngx_log.c
index 770a59084..c0485c61b 100644
--- a/src/core/ngx_log.c
+++ b/src/core/ngx_log.c
@@ -429,8 +429,7 @@ ngx_error_log(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
     value = cf->args->elts;
 
     if (ngx_strcmp(value[1].data, "stderr") == 0) {
-        name.len = 0;
-        name.data = NULL;
+        ngx_str_null(&name);
 
     } else {
         name = value[1];
diff --git a/src/core/ngx_string.h b/src/core/ngx_string.h
index b29bdda3d..53b942297 100644
--- a/src/core/ngx_string.h
+++ b/src/core/ngx_string.h
@@ -38,6 +38,9 @@ typedef struct {
 
 #define ngx_string(str)     { sizeof(str) - 1, (u_char *) str }
 #define ngx_null_string     { 0, NULL }
+#define ngx_str_set(str, text)                                               \
+    (str)->len = sizeof(text) - 1; (str)->data = (u_char *) text
+#define ngx_str_null(str)   (str)->len = 0; (str)->data = NULL
 
 
 #define ngx_tolower(c)      (u_char) ((c >= 'A' && c <= 'Z') ? (c | 0x20) : c)
diff --git a/src/event/ngx_event_openssl.c b/src/event/ngx_event_openssl.c
index 5eab4affb..04baa81f8 100644
--- a/src/event/ngx_event_openssl.c
+++ b/src/event/ngx_event_openssl.c
@@ -2234,21 +2234,17 @@ ngx_ssl_get_client_verify(ngx_connection_t *c, ngx_pool_t *pool, ngx_str_t *s)
     X509  *cert;
 
     if (SSL_get_verify_result(c->ssl->connection) != X509_V_OK) {
-        s->len = sizeof("FAILED") - 1;
-        s->data = (u_char *) "FAILED";
-
+        ngx_str_set(s, "FAILED");
         return NGX_OK;
     }
 
     cert = SSL_get_peer_certificate(c->ssl->connection);
 
     if (cert) {
-        s->len = sizeof("SUCCESS") - 1;
-        s->data = (u_char *) "SUCCESS";
+        ngx_str_set(s, "SUCCESS");
 
     } else {
-        s->len = sizeof("NONE") - 1;
-        s->data = (u_char *) "NONE";
+        ngx_str_set(s, "NONE");
     }
 
     X509_free(cert);
diff --git a/src/http/modules/ngx_http_auth_basic_module.c b/src/http/modules/ngx_http_auth_basic_module.c
index c9ce694ef..a6b95fa1d 100644
--- a/src/http/modules/ngx_http_auth_basic_module.c
+++ b/src/http/modules/ngx_http_auth_basic_module.c
@@ -348,8 +348,7 @@ ngx_http_auth_basic_set_realm(ngx_http_request_t *r, ngx_str_t *realm)
     }
 
     r->headers_out.www_authenticate->hash = 1;
-    r->headers_out.www_authenticate->key.len = sizeof("WWW-Authenticate") - 1;
-    r->headers_out.www_authenticate->key.data = (u_char *) "WWW-Authenticate";
+    ngx_str_set(&r->headers_out.www_authenticate->key, "WWW-Authenticate");
     r->headers_out.www_authenticate->value = *realm;
 
     return NGX_HTTP_UNAUTHORIZED;
@@ -425,9 +424,7 @@ ngx_http_auth_basic(ngx_conf_t *cf, void *post, void *data)
     u_char  *basic, *p;
 
     if (ngx_strcmp(realm->data, "off") == 0) {
-        realm->len = 0;
-        realm->data = (u_char *) "";
-
+        ngx_str_set(realm, "");
         return NGX_CONF_OK;
     }
 
diff --git a/src/http/modules/ngx_http_autoindex_module.c b/src/http/modules/ngx_http_autoindex_module.c
index 698b7636c..9dc48702f 100644
--- a/src/http/modules/ngx_http_autoindex_module.c
+++ b/src/http/modules/ngx_http_autoindex_module.c
@@ -235,8 +235,7 @@ ngx_http_autoindex_handler(ngx_http_request_t *r)
 
     r->headers_out.status = NGX_HTTP_OK;
     r->headers_out.content_type_len = sizeof("text/html") - 1;
-    r->headers_out.content_type.len = sizeof("text/html") - 1;
-    r->headers_out.content_type.data = (u_char *) "text/html";
+    ngx_str_set(&r->headers_out.content_type, "text/html");
 
     rc = ngx_http_send_header(r);
 
diff --git a/src/http/modules/ngx_http_empty_gif_module.c b/src/http/modules/ngx_http_empty_gif_module.c
index e6515df15..35c4415b3 100644
--- a/src/http/modules/ngx_http_empty_gif_module.c
+++ b/src/http/modules/ngx_http_empty_gif_module.c
@@ -123,8 +123,7 @@ ngx_http_empty_gif_handler(ngx_http_request_t *r)
     }
 
     r->headers_out.content_type_len = sizeof("image/gif") - 1;
-    r->headers_out.content_type.len = sizeof("image/gif") - 1;
-    r->headers_out.content_type.data = (u_char *) "image/gif";
+    ngx_str_set(&r->headers_out.content_type, "image/gif");
 
     if (r->method == NGX_HTTP_HEAD) {
         r->headers_out.status = NGX_HTTP_OK;
diff --git a/src/http/modules/ngx_http_fastcgi_module.c b/src/http/modules/ngx_http_fastcgi_module.c
index 77b6d9d38..162eca87b 100644
--- a/src/http/modules/ngx_http_fastcgi_module.c
+++ b/src/http/modules/ngx_http_fastcgi_module.c
@@ -589,9 +589,7 @@ ngx_http_fastcgi_handler(ngx_http_request_t *r)
 
     u = r->upstream;
 
-    u->schema.len = sizeof("fastcgi://") - 1;
-    u->schema.data = (u_char *) "fastcgi://";
-
+    ngx_str_set(&u->schema, "fastcgi://");
     u->output.tag = (ngx_buf_tag_t) &ngx_http_fastcgi_module;
 
     u->conf = &flcf->upstream;
@@ -1449,15 +1447,12 @@ ngx_http_fastcgi_process_header(ngx_http_request_t *r)
 
                 } else if (u->headers_in.location) {
                     u->headers_in.status_n = 302;
-                    u->headers_in.status_line.len =
-                                           sizeof("302 Moved Temporarily") - 1;
-                    u->headers_in.status_line.data =
-                                           (u_char *) "302 Moved Temporarily";
+                    ngx_str_set(&u->headers_in.status_line,
+                                "302 Moved Temporarily");
 
                 } else {
                     u->headers_in.status_n = 200;
-                    u->headers_in.status_line.len = sizeof("200 OK") - 1;
-                    u->headers_in.status_line.data = (u_char *) "200 OK";
+                    ngx_str_set(&u->headers_in.status_line, "200 OK");
                 }
 
                 if (u->state) {
@@ -1922,8 +1917,7 @@ ngx_http_fastcgi_create_loc_conf(ngx_conf_t *cf)
      *     conf->upstream.store_lengths = NULL;
      *     conf->upstream.store_values = NULL;
      *
-     *     conf->index.len = 0;
-     *     conf->index.data = NULL;
+     *     conf->index.len = { 0, NULL };
      */
 
     conf->upstream.store = NGX_CONF_UNSET;
diff --git a/src/http/modules/ngx_http_gzip_filter_module.c b/src/http/modules/ngx_http_gzip_filter_module.c
index 879971ffb..e2b204ba2 100644
--- a/src/http/modules/ngx_http_gzip_filter_module.c
+++ b/src/http/modules/ngx_http_gzip_filter_module.c
@@ -285,11 +285,8 @@ ngx_http_gzip_header_filter(ngx_http_request_t *r)
     }
 
     h->hash = 1;
-    h->key.len = sizeof("Content-Encoding") - 1;
-    h->key.data = (u_char *) "Content-Encoding";
-    h->value.len = sizeof("gzip") - 1;
-    h->value.data = (u_char *) "gzip";
-
+    ngx_str_set(&h->key, "Content-Encoding");
+    ngx_str_set(&h->value, "gzip");
     r->headers_out.content_encoding = h;
 
     r->main_filter_need_in_memory = 1;
diff --git a/src/http/modules/ngx_http_gzip_static_module.c b/src/http/modules/ngx_http_gzip_static_module.c
index 2098d8c43..0c6dbbb4a 100644
--- a/src/http/modules/ngx_http_gzip_static_module.c
+++ b/src/http/modules/ngx_http_gzip_static_module.c
@@ -212,12 +212,10 @@ ngx_http_gzip_static_handler(ngx_http_request_t *r)
     }
 
     h->hash = 1;
-    h->key.len = sizeof("Content-Encoding") - 1;
-    h->key.data = (u_char *) "Content-Encoding";
-    h->value.len = sizeof("gzip") - 1;
-    h->value.data = (u_char *) "gzip";
-
+    ngx_str_set(&h->key, "Content-Encoding");
+    ngx_str_set(&h->value, "gzip");
     r->headers_out.content_encoding = h;
+
     r->ignore_content_encoding = 1;
 
     /* we need to allocate all before the header would be sent */
diff --git a/src/http/modules/ngx_http_headers_filter_module.c b/src/http/modules/ngx_http_headers_filter_module.c
index fb6c0050e..1d409582c 100644
--- a/src/http/modules/ngx_http_headers_filter_module.c
+++ b/src/http/modules/ngx_http_headers_filter_module.c
@@ -196,8 +196,7 @@ ngx_http_set_expires(ngx_http_request_t *r, ngx_http_headers_conf_t *conf)
         r->headers_out.expires = expires;
 
         expires->hash = 1;
-        expires->key.len = sizeof("Expires") - 1;
-        expires->key.data = (u_char *) "Expires";
+        ngx_str_set(&expires->key, "Expires");
     }
 
     len = sizeof("Mon, 28 Sep 1970 06:00:00 GMT");
@@ -225,9 +224,7 @@ ngx_http_set_expires(ngx_http_request_t *r, ngx_http_headers_conf_t *conf)
         }
 
         cc->hash = 1;
-        cc->key.len = sizeof("Cache-Control") - 1;
-        cc->key.data = (u_char *) "Cache-Control";
-
+        ngx_str_set(&cc->key, "Cache-Control");
         *ccp = cc;
 
     } else {
@@ -240,20 +237,14 @@ ngx_http_set_expires(ngx_http_request_t *r, ngx_http_headers_conf_t *conf)
 
     if (conf->expires == NGX_HTTP_EXPIRES_EPOCH) {
         expires->value.data = (u_char *) "Thu, 01 Jan 1970 00:00:01 GMT";
-
-        cc->value.len = sizeof("no-cache") - 1;
-        cc->value.data = (u_char *) "no-cache";
-
+        ngx_str_set(&cc->value, "no-cache");
         return NGX_OK;
     }
 
     if (conf->expires == NGX_HTTP_EXPIRES_MAX) {
         expires->value.data = (u_char *) "Thu, 31 Dec 2037 23:55:55 GMT";
-
         /* 10 years */
-        cc->value.len = sizeof("max-age=315360000") - 1;
-        cc->value.data = (u_char *) "max-age=315360000";
-
+        ngx_str_set(&cc->value, "max-age=315360000");
         return NGX_OK;
     }
 
@@ -265,10 +256,7 @@ ngx_http_set_expires(ngx_http_request_t *r, ngx_http_headers_conf_t *conf)
     if (conf->expires_time == 0) {
         ngx_memcpy(expires->value.data, ngx_cached_http_time.data,
                    ngx_cached_http_time.len + 1);
-
-        cc->value.len = sizeof("max-age=0") - 1;
-        cc->value.data = (u_char *) "max-age=0";
-
+        ngx_str_set(&cc->value, "max-age=0");
         return NGX_OK;
     }
 
@@ -292,9 +280,7 @@ ngx_http_set_expires(ngx_http_request_t *r, ngx_http_headers_conf_t *conf)
     ngx_http_time(expires->value.data, expires_time);
 
     if (conf->expires_time < 0 || max_age < 0) {
-        cc->value.len = sizeof("no-cache") - 1;
-        cc->value.data = (u_char *) "no-cache";
-
+        ngx_str_set(&cc->value, "no-cache");
         return NGX_OK;
     }
 
@@ -361,8 +347,7 @@ ngx_http_add_cache_control(ngx_http_request_t *r, ngx_http_header_val_t *hv,
     }
 
     cc->hash = 1;
-    cc->key.len = sizeof("Cache-Control") - 1;
-    cc->key.data = (u_char *) "Cache-Control";
+    ngx_str_set(&cc->key, "Cache-Control");
     cc->value = *value;
 
     *ccp = cc;
diff --git a/src/http/modules/ngx_http_image_filter_module.c b/src/http/modules/ngx_http_image_filter_module.c
index 6511317c6..b5f8425a8 100644
--- a/src/http/modules/ngx_http_image_filter_module.c
+++ b/src/http/modules/ngx_http_image_filter_module.c
@@ -529,8 +529,7 @@ ngx_http_image_json(ngx_http_request_t *r, ngx_http_image_filter_ctx_t *ctx)
     ngx_http_clean_header(r);
 
     r->headers_out.status = NGX_HTTP_OK;
-    r->headers_out.content_type.len = sizeof("text/plain") - 1;
-    r->headers_out.content_type.data = (u_char *) "text/plain";
+    ngx_str_set(&r->headers_out.content_type, "text/plain");
     r->headers_out.content_type_lowcase = NULL;
 
     if (ctx == NULL) {
diff --git a/src/http/modules/ngx_http_log_module.c b/src/http/modules/ngx_http_log_module.c
index 1796ee27f..5f356c357 100644
--- a/src/http/modules/ngx_http_log_module.c
+++ b/src/http/modules/ngx_http_log_module.c
@@ -747,8 +747,7 @@ ngx_http_log_create_main_conf(ngx_conf_t *cf)
         return NULL;
     }
 
-    fmt->name.len = sizeof("combined") - 1;
-    fmt->name.data = (u_char *) "combined";
+    ngx_str_set(&fmt->name, "combined");
 
     fmt->flushes = NULL;
 
@@ -922,8 +921,7 @@ ngx_http_log_set_log(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
         }
 
     } else {
-        name.len = sizeof("combined") - 1;
-        name.data = (u_char *) "combined";
+        ngx_str_set(&name, "combined");
         lmcf->combined_used = 1;
     }
 
diff --git a/src/http/modules/ngx_http_memcached_module.c b/src/http/modules/ngx_http_memcached_module.c
index 090a285d3..607e319a5 100644
--- a/src/http/modules/ngx_http_memcached_module.c
+++ b/src/http/modules/ngx_http_memcached_module.c
@@ -189,9 +189,7 @@ ngx_http_memcached_handler(ngx_http_request_t *r)
 
     u = r->upstream;
 
-    u->schema.len = sizeof("memcached://") - 1;
-    u->schema.data = (u_char *) "memcached://";
-
+    ngx_str_set(&u->schema, "memcached://");
     u->output.tag = (ngx_buf_tag_t) &ngx_http_memcached_module;
 
     mlcf = ngx_http_get_module_loc_conf(r, ngx_http_memcached_module);
diff --git a/src/http/modules/ngx_http_proxy_module.c b/src/http/modules/ngx_http_proxy_module.c
index 7b2e077ec..1db26576b 100644
--- a/src/http/modules/ngx_http_proxy_module.c
+++ b/src/http/modules/ngx_http_proxy_module.c
@@ -1568,10 +1568,8 @@ ngx_http_proxy_process_header(ngx_http_request_t *r)
                 h->hash = ngx_hash(ngx_hash(ngx_hash(ngx_hash(
                                     ngx_hash('s', 'e'), 'r'), 'v'), 'e'), 'r');
 
-                h->key.len = sizeof("Server") - 1;
-                h->key.data = (u_char *) "Server";
-                h->value.len = 0;
-                h->value.data = NULL;
+                ngx_str_set(&h->key, "Server");
+                ngx_str_null(&h->value);
                 h->lowcase_key = (u_char *) "server";
             }
 
@@ -1583,10 +1581,8 @@ ngx_http_proxy_process_header(ngx_http_request_t *r)
 
                 h->hash = ngx_hash(ngx_hash(ngx_hash('d', 'a'), 't'), 'e');
 
-                h->key.len = sizeof("Date") - 1;
-                h->key.data = (u_char *) "Date";
-                h->value.len = 0;
-                h->value.data = NULL;
+                ngx_str_set(&h->key, "Date");
+                ngx_str_null(&h->value);
                 h->lowcase_key = (u_char *) "date";
             }
 
@@ -2222,8 +2218,7 @@ ngx_http_proxy_merge_loc_conf(ngx_conf_t *cf, void *parent, void *child)
                 pr->replacement.text = conf->location;
 
             } else {
-                pr->replacement.text.len = 0;
-                pr->replacement.text.data = NULL;
+                ngx_str_null(&pr->replacement.text);
             }
         }
     }
@@ -2311,10 +2306,8 @@ ngx_http_proxy_merge_loc_conf(ngx_conf_t *cf, void *parent, void *child)
             return NGX_CONF_ERROR;
         }
 
-        s->key.len = sizeof("Content-Length") - 1;
-        s->key.data = (u_char *) "Content-Length";
-        s->value.len = sizeof("$proxy_internal_body_length") - 1;
-        s->value.data = (u_char *) "$proxy_internal_body_length";
+        ngx_str_set(&s->key, "Content-Length");
+        ngx_str_set(&s->value, "$proxy_internal_body_length");
     }
 
     if (ngx_http_proxy_merge_headers(cf, conf, prev) != NGX_OK) {
@@ -2777,8 +2770,7 @@ ngx_http_proxy_redirect(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
             pr->replacement.text = plcf->location;
 
         } else {
-            pr->replacement.text.len = 0;
-            pr->replacement.text.data = NULL;
+            ngx_str_null(&pr->replacement.text);
         }
 
         return NGX_CONF_OK;
@@ -3038,12 +3030,10 @@ ngx_http_proxy_set_vars(ngx_url_t *u, ngx_http_proxy_vars_t *v)
             v->host_header = u->host;
 
             if (u->default_port == 80) {
-                v->port.len = sizeof("80") - 1;
-                v->port.data = (u_char *) "80";
+                ngx_str_set(&v->port, "80");
 
             } else {
-                v->port.len = sizeof("443") - 1;
-                v->port.data = (u_char *) "443";
+                ngx_str_set(&v->port, "443");
             }
 
         } else {
@@ -3055,10 +3045,8 @@ ngx_http_proxy_set_vars(ngx_url_t *u, ngx_http_proxy_vars_t *v)
         v->key_start.len += v->host_header.len;
 
     } else {
-        v->host_header.len = sizeof("localhost") - 1;
-        v->host_header.data = (u_char *) "localhost";
-        v->port.len = 0;
-        v->port.data = (u_char *) "";
+        ngx_str_set(&v->host_header, "localhost");
+        ngx_str_null(&v->port);
         v->key_start.len += sizeof("unix:") - 1 + u->host.len + 1;
     }
 
diff --git a/src/http/modules/ngx_http_range_filter_module.c b/src/http/modules/ngx_http_range_filter_module.c
index bc2840831..e11240660 100644
--- a/src/http/modules/ngx_http_range_filter_module.c
+++ b/src/http/modules/ngx_http_range_filter_module.c
@@ -224,10 +224,8 @@ next_filter:
     }
 
     r->headers_out.accept_ranges->hash = 1;
-    r->headers_out.accept_ranges->key.len = sizeof("Accept-Ranges") - 1;
-    r->headers_out.accept_ranges->key.data = (u_char *) "Accept-Ranges";
-    r->headers_out.accept_ranges->value.len = sizeof("bytes") - 1;
-    r->headers_out.accept_ranges->value.data = (u_char *) "bytes";
+    ngx_str_set(&r->headers_out.accept_ranges->key, "Accept-Ranges");
+    ngx_str_set(&r->headers_out.accept_ranges->value, "bytes");
 
     return ngx_http_next_header_filter(r);
 }
@@ -355,8 +353,7 @@ ngx_http_range_singlepart_header(ngx_http_request_t *r,
     r->headers_out.content_range = content_range;
 
     content_range->hash = 1;
-    content_range->key.len = sizeof("Content-Range") - 1;
-    content_range->key.data = (u_char *) "Content-Range";
+    ngx_str_set(&content_range->key, "Content-Range");
 
     content_range->value.data = ngx_pnalloc(r->pool,
                                     sizeof("bytes -/") - 1 + 3 * NGX_OFF_T_LEN);
@@ -520,8 +517,7 @@ ngx_http_range_not_satisfiable(ngx_http_request_t *r)
     r->headers_out.content_range = content_range;
 
     content_range->hash = 1;
-    content_range->key.len = sizeof("Content-Range") - 1;
-    content_range->key.data = (u_char *) "Content-Range";
+    ngx_str_set(&content_range->key, "Content-Range");
 
     content_range->value.data = ngx_pnalloc(r->pool,
                                        sizeof("bytes */") - 1 + NGX_OFF_T_LEN);
diff --git a/src/http/modules/ngx_http_referer_module.c b/src/http/modules/ngx_http_referer_module.c
index 78cc7f4dd..8530084d5 100644
--- a/src/http/modules/ngx_http_referer_module.c
+++ b/src/http/modules/ngx_http_referer_module.c
@@ -363,8 +363,7 @@ ngx_http_valid_referers(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
     ngx_http_server_name_t    *sn;
     ngx_http_core_srv_conf_t  *cscf;
 
-    name.len = sizeof("invalid_referer") - 1;
-    name.data = (u_char *) "invalid_referer";
+    ngx_str_set(&name, "invalid_referer");
 
     var = ngx_http_add_variable(cf, &name,
                                 NGX_HTTP_VAR_CHANGEABLE|NGX_HTTP_VAR_NOHASH);
@@ -407,8 +406,7 @@ ngx_http_valid_referers(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
             continue;
         }
 
-        uri.len = 0;
-        uri.data = NULL;
+        ngx_str_null(&uri);
 
         if (ngx_strcmp(value[i].data, "server_names") == 0) {
 
diff --git a/src/http/modules/ngx_http_ssi_filter_module.c b/src/http/modules/ngx_http_ssi_filter_module.c
index 7a2beede1..b994711e7 100644
--- a/src/http/modules/ngx_http_ssi_filter_module.c
+++ b/src/http/modules/ngx_http_ssi_filter_module.c
@@ -346,13 +346,9 @@ ngx_http_ssi_header_filter(ngx_http_request_t *r)
     ctx->params.nalloc = NGX_HTTP_SSI_PARAMS_N;
     ctx->params.pool = r->pool;
 
-    ctx->timefmt.len = sizeof("%A, %d-%b-%Y %H:%M:%S %Z") - 1;
-    ctx->timefmt.data = (u_char *) "%A, %d-%b-%Y %H:%M:%S %Z";
-
-    ctx->errmsg.len =
-              sizeof("[an error occurred while processing the directive]") - 1;
-    ctx->errmsg.data = (u_char *)
-                     "[an error occurred while processing the directive]";
+    ngx_str_set(&ctx->timefmt, "%A, %d-%b-%Y %H:%M:%S %Z");
+    ngx_str_set(&ctx->errmsg,
+                "[an error occurred while processing the directive]");
 
     r->filter_need_in_memory = 1;
 
@@ -1904,8 +1900,7 @@ ngx_http_ssi_include(ngx_http_request_t *r, ngx_http_ssi_ctx_t *ctx,
     ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
                    "ssi include: \"%V\"", uri);
 
-    args.len = 0;
-    args.data = NULL;
+    ngx_str_null(&args);
     flags = NGX_HTTP_LOG_UNSAFE;
 
     if (ngx_http_parse_unsafe_uri(r, uri, &args, &flags) != NGX_OK) {
diff --git a/src/http/modules/ngx_http_ssl_module.c b/src/http/modules/ngx_http_ssl_module.c
index 3fe0d4366..ee6cc6f05 100644
--- a/src/http/modules/ngx_http_ssl_module.c
+++ b/src/http/modules/ngx_http_ssl_module.c
@@ -314,8 +314,7 @@ ngx_http_ssl_create_srv_conf(ngx_conf_t *cf)
      *     sscf->dhparam = { 0, NULL };
      *     sscf->client_certificate = { 0, NULL };
      *     sscf->crl = { 0, NULL };
-     *     sscf->ciphers.len = 0;
-     *     sscf->ciphers.data = NULL;
+     *     sscf->ciphers = { 0, NULL };
      *     sscf->shm_zone = NULL;
      */
 
diff --git a/src/http/modules/ngx_http_stub_status_module.c b/src/http/modules/ngx_http_stub_status_module.c
index 9d2d074b2..4b74eb884 100644
--- a/src/http/modules/ngx_http_stub_status_module.c
+++ b/src/http/modules/ngx_http_stub_status_module.c
@@ -75,8 +75,7 @@ static ngx_int_t ngx_http_status_handler(ngx_http_request_t *r)
         return rc;
     }
 
-    r->headers_out.content_type.len = sizeof("text/plain") - 1;
-    r->headers_out.content_type.data = (u_char *) "text/plain";
+    ngx_str_set(&r->headers_out.content_type, "text/plain");
 
     if (r->method == NGX_HTTP_HEAD) {
         r->headers_out.status = NGX_HTTP_OK;
diff --git a/src/http/modules/ngx_http_userid_filter_module.c b/src/http/modules/ngx_http_userid_filter_module.c
index 2a5dbb7d4..03efd3a8a 100644
--- a/src/http/modules/ngx_http_userid_filter_module.c
+++ b/src/http/modules/ngx_http_userid_filter_module.c
@@ -493,8 +493,7 @@ ngx_http_userid_set_uid(ngx_http_request_t *r, ngx_http_userid_ctx_t *ctx,
     }
 
     set_cookie->hash = 1;
-    set_cookie->key.len = sizeof("Set-Cookie") - 1;
-    set_cookie->key.data = (u_char *) "Set-Cookie";
+    ngx_str_set(&set_cookie->key, "Set-Cookie");
     set_cookie->value.len = p - cookie;
     set_cookie->value.data = cookie;
 
@@ -511,8 +510,7 @@ ngx_http_userid_set_uid(ngx_http_request_t *r, ngx_http_userid_ctx_t *ctx,
     }
 
     p3p->hash = 1;
-    p3p->key.len = sizeof("P3P") - 1;
-    p3p->key.data = (u_char *) "P3P";
+    ngx_str_set(&p3p->key, "P3P");
     p3p->value = conf->p3p;
 
     return NGX_OK;
@@ -576,14 +574,10 @@ ngx_http_userid_create_conf(ngx_conf_t *cf)
     /*
      * set by ngx_pcalloc():
      *
-     *     conf->name.len = 0;
-     *     conf->name.date = NULL;
-     *     conf->domain.len = 0;
-     *     conf->domain.date = NULL;
-     *     conf->path.len = 0;
-     *     conf->path.date = NULL;
-     *     conf->p3p.len = 0;
-     *     conf->p3p.date = NULL;
+     *     conf->name = { 0, NULL };
+     *     conf->domain = { 0, NULL };
+     *     conf->path = { 0, NULL };
+     *     conf->p3p = { 0, NULL };
      */
 
     conf->enable = NGX_CONF_UNSET_UINT;
@@ -642,9 +636,7 @@ ngx_http_userid_domain(ngx_conf_t *cf, void *post, void *data)
     u_char  *p, *new;
 
     if (ngx_strcmp(domain->data, "none") == 0) {
-        domain->len = 0;
-        domain->data = (u_char *) "";
-
+        ngx_str_set(domain, "");
         return NGX_CONF_OK;
     }
 
@@ -727,8 +719,7 @@ ngx_http_userid_p3p(ngx_conf_t *cf, void *post, void *data)
     ngx_str_t  *p3p = data;
 
     if (ngx_strcmp(p3p->data, "none") == 0) {
-        p3p->len = 0;
-        p3p->data = (u_char *) "";
+        ngx_str_set(p3p, "");
     }
 
     return NGX_CONF_OK;
diff --git a/src/http/modules/ngx_http_xslt_filter_module.c b/src/http/modules/ngx_http_xslt_filter_module.c
index bb11afa4c..a06b26c28 100644
--- a/src/http/modules/ngx_http_xslt_filter_module.c
+++ b/src/http/modules/ngx_http_xslt_filter_module.c
@@ -837,8 +837,7 @@ ngx_http_xslt_apply_stylesheet(ngx_http_request_t *r,
     } else if (doc_type == XML_HTML_DOCUMENT_NODE) {
 
         r->headers_out.content_type_len = sizeof("text/html") - 1;
-        r->headers_out.content_type.len = sizeof("text/html") - 1;
-        r->headers_out.content_type.data = (u_char *) "text/html";
+        ngx_str_set(&r->headers_out.content_type, "text/html");
     }
 
     r->headers_out.content_type_lowcase = NULL;
diff --git a/src/http/modules/perl/ngx_http_perl_module.c b/src/http/modules/perl/ngx_http_perl_module.c
index e1388f1c1..5096b506d 100644
--- a/src/http/modules/perl/ngx_http_perl_module.c
+++ b/src/http/modules/perl/ngx_http_perl_module.c
@@ -481,8 +481,7 @@ ngx_http_perl_init_interpreter(ngx_conf_t *cf, ngx_http_perl_main_conf_t *pmcf)
             return NGX_CONF_ERROR;
         }
 
-        m->len = sizeof(NGX_PERL_MODULES) - 1;
-        m->data = NGX_PERL_MODULES;
+        ngx_str_set(m, NGX_PERL_MODULES);
     }
 #endif
 
diff --git a/src/http/ngx_http_core_module.c b/src/http/ngx_http_core_module.c
index 29ff64c08..23e938897 100644
--- a/src/http/ngx_http_core_module.c
+++ b/src/http/ngx_http_core_module.c
@@ -1685,8 +1685,7 @@ ngx_http_set_exten(ngx_http_request_t *r)
 {
     ngx_int_t  i;
 
-    r->exten.len = 0;
-    r->exten.data = NULL;
+    ngx_str_null(&r->exten);
 
     for (i = r->uri.len - 1; i > 1; i--) {
         if (r->uri.data[i] == '.' && r->uri.data[i - 1] != '/') {
@@ -2187,8 +2186,7 @@ ngx_http_internal_redirect(ngx_http_request_t *r,
         r->args = *args;
 
     } else {
-        r->args.len = 0;
-        r->args.data = NULL;
+        ngx_str_null(&r->args);
     }
 
     ngx_log_debug2(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
@@ -3032,8 +3030,7 @@ ngx_http_core_merge_loc_conf(ngx_conf_t *cf, void *parent, void *child)
         conf->root_values = prev->root_values;
 
         if (prev->root.data == NULL) {
-            conf->root.len = sizeof("html") - 1;
-            conf->root.data = (u_char *) "html";
+            ngx_str_set(&conf->root, "html");
 
             if (ngx_conf_full_name(cf->cycle, &conf->root, 0) != NGX_OK) {
                 return NGX_CONF_ERROR;
@@ -3891,8 +3888,7 @@ ngx_http_core_error_page(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
         return NGX_CONF_ERROR;
     }
 
-    args.len = 0;
-    args.data = NULL;
+    ngx_str_null(&args);
 
     if (cv.lengths == NULL && uri.data[0] == '/') {
         p = (u_char *) ngx_strchr(uri.data, '?');
diff --git a/src/http/ngx_http_header_filter_module.c b/src/http/ngx_http_header_filter_module.c
index 4f4023632..c62d7233f 100644
--- a/src/http/ngx_http_header_filter_module.c
+++ b/src/http/ngx_http_header_filter_module.c
@@ -218,8 +218,7 @@ ngx_http_header_filter(ngx_http_request_t *r)
 
             if (status == NGX_HTTP_NO_CONTENT) {
                 r->header_only = 1;
-                r->headers_out.content_type.len = 0;
-                r->headers_out.content_type.data = NULL;
+                ngx_str_null(&r->headers_out.content_type);
                 r->headers_out.last_modified_time = -1;
                 r->headers_out.last_modified = NULL;
                 r->headers_out.content_length = NULL;
@@ -371,8 +370,7 @@ ngx_http_header_filter(ngx_http_request_t *r)
         }
 
     } else {
-        host.len = 0;
-        host.data = NULL;
+        ngx_str_null(&host);
         port = 0;
     }
 
@@ -539,8 +537,7 @@ ngx_http_header_filter(ngx_http_request_t *r)
 
         r->headers_out.location->value.len = b->last - p;
         r->headers_out.location->value.data = p;
-        r->headers_out.location->key.len = sizeof("Location") - 1;
-        r->headers_out.location->key.data = (u_char *) "Location";
+        ngx_str_set(&r->headers_out.location->key, "Location");
 
         *b->last++ = CR; *b->last++ = LF;
     }
diff --git a/src/http/ngx_http_script.c b/src/http/ngx_http_script.c
index aa03df007..5ccce003c 100644
--- a/src/http/ngx_http_script.c
+++ b/src/http/ngx_http_script.c
@@ -1008,8 +1008,7 @@ ngx_http_script_regex_end_code(ngx_http_script_engine_t *e)
         }
 
         r->headers_out.location->hash = 1;
-        r->headers_out.location->key.len = sizeof("Location") - 1;
-        r->headers_out.location->key.data = (u_char *) "Location";
+        ngx_str_set(&r->headers_out.location->key, "Location");
         r->headers_out.location->value = e->buf;
 
         e->ip += sizeof(ngx_http_script_regex_end_code_t);
diff --git a/src/http/ngx_http_special_response.c b/src/http/ngx_http_special_response.c
index 060cc9934..5c032f3a5 100644
--- a/src/http/ngx_http_special_response.c
+++ b/src/http/ngx_http_special_response.c
@@ -553,8 +553,7 @@ ngx_http_send_error_page(ngx_http_request_t *r, ngx_http_err_page_t *err_page)
     r->err_status = NGX_HTTP_MOVED_TEMPORARILY;
 
     location->hash = 1;
-    location->key.len = sizeof("Location") - 1;
-    location->key.data = (u_char *) "Location";
+    ngx_str_set(&location->key, "Location");
     location->value = uri;
 
     r->headers_out.location = location;
@@ -608,8 +607,7 @@ ngx_http_send_special_response(ngx_http_request_t *r,
             }
 
             r->headers_out.content_type_len = sizeof("text/html") - 1;
-            r->headers_out.content_type.len = sizeof("text/html") - 1;
-            r->headers_out.content_type.data = (u_char *) "text/html";
+            ngx_str_set(&r->headers_out.content_type, "text/html");
             r->headers_out.content_type_lowcase = NULL;
 
         } else {
@@ -711,8 +709,7 @@ ngx_http_send_refresh(ngx_http_request_t *r)
     r->err_status = NGX_HTTP_OK;
 
     r->headers_out.content_type_len = sizeof("text/html") - 1;
-    r->headers_out.content_type.len = sizeof("text/html") - 1;
-    r->headers_out.content_type.data = (u_char *) "text/html";
+    ngx_str_set(&r->headers_out.content_type, "text/html");
     r->headers_out.content_type_lowcase = NULL;
 
     r->headers_out.location->hash = 0;
diff --git a/src/http/ngx_http_upstream.c b/src/http/ngx_http_upstream.c
index 522a60536..e6bef3c04 100644
--- a/src/http/ngx_http_upstream.c
+++ b/src/http/ngx_http_upstream.c
@@ -1800,8 +1800,7 @@ ngx_http_upstream_process_headers(ngx_http_request_t *r, ngx_http_upstream_t *u)
         }
 
         uri = &u->headers_in.x_accel_redirect->value;
-        args.len = 0;
-        args.data = NULL;
+        ngx_str_null(&args);
         flags = NGX_HTTP_LOG_UNSAFE;
 
         if (ngx_http_parse_unsafe_uri(r, uri, &args, &flags) != NGX_OK) {
diff --git a/src/http/ngx_http_variables.c b/src/http/ngx_http_variables.c
index c8d1c8dcb..0bba28128 100644
--- a/src/http/ngx_http_variables.c
+++ b/src/http/ngx_http_variables.c
@@ -1390,8 +1390,7 @@ ngx_http_variable_sent_location(ngx_http_request_t *r,
         return NGX_OK;
     }
 
-    name.len = sizeof("sent_http_location") - 1;
-    name.data = (u_char *) "sent_http_location";
+    ngx_str_set(&name, "sent_http_location");
 
     return ngx_http_variable_unknown_header(v, &name,
                                             &r->headers_out.headers.part,
diff --git a/src/mail/ngx_mail_auth_http_module.c b/src/mail/ngx_mail_auth_http_module.c
index b9f963578..d54a392ac 100644
--- a/src/mail/ngx_mail_auth_http_module.c
+++ b/src/mail/ngx_mail_auth_http_module.c
@@ -1409,15 +1409,13 @@ ngx_mail_auth_http(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
         ahcf->host_header = u.host;
 
     } else {
-        ahcf->host_header.len = sizeof("localhost") - 1;
-        ahcf->host_header.data = (u_char *) "localhost";
+        ngx_str_set(&ahcf->host_header, "localhost");
     }
 
     ahcf->uri = u.uri;
 
     if (ahcf->uri.len == 0) {
-        ahcf->uri.len = sizeof("/") - 1;
-        ahcf->uri.data = (u_char *) "/";
+        ngx_str_set(&ahcf->uri, "/");
     }
 
     return NGX_CONF_OK;
diff --git a/src/mail/ngx_mail_imap_handler.c b/src/mail/ngx_mail_imap_handler.c
index a2e032eff..f15dbec80 100644
--- a/src/mail/ngx_mail_imap_handler.c
+++ b/src/mail/ngx_mail_imap_handler.c
@@ -39,8 +39,7 @@ ngx_mail_imap_init_session(ngx_mail_session_t *s, ngx_connection_t *c)
 
     cscf = ngx_mail_get_module_srv_conf(s, ngx_mail_core_module);
 
-    s->out.len = sizeof(imap_greeting) - 1;
-    s->out.data = imap_greeting;
+    ngx_str_set(&s->out, imap_greeting);
 
     c->read->handler = ngx_mail_imap_init_protocol;
 
@@ -136,8 +135,7 @@ ngx_mail_imap_auth_state(ngx_event_t *rev)
 
     tag = 1;
     s->text.len = 0;
-    s->out.len = sizeof(imap_ok) - 1;
-    s->out.data = imap_ok;
+    ngx_str_set(&s->out, imap_ok);
 
     if (rc == NGX_OK) {
 
@@ -186,8 +184,7 @@ ngx_mail_imap_auth_state(ngx_event_t *rev)
 
             case NGX_IMAP_LOGOUT:
                 s->quit = 1;
-                s->text.len = sizeof(imap_bye) - 1;
-                s->text.data = imap_bye;
+                ngx_str_set(&s->text, imap_bye);
                 break;
 
             case NGX_IMAP_NOOP:
@@ -208,8 +205,7 @@ ngx_mail_imap_auth_state(ngx_event_t *rev)
             rc = ngx_mail_auth_login_username(s, c, 0);
 
             tag = 0;
-            s->out.len = sizeof(imap_password) - 1;
-            s->out.data = imap_password;
+            ngx_str_set(&s->out, imap_password);
             s->mail_state = ngx_imap_auth_login_password;
 
             break;
@@ -229,8 +225,7 @@ ngx_mail_imap_auth_state(ngx_event_t *rev)
 
     } else if (rc == NGX_IMAP_NEXT) {
         tag = 0;
-        s->out.len = sizeof(imap_next) - 1;
-        s->out.data = imap_next;
+        ngx_str_set(&s->out, imap_next);
     }
 
     switch (rc) {
@@ -245,16 +240,14 @@ ngx_mail_imap_auth_state(ngx_event_t *rev)
 
     case NGX_MAIL_PARSE_INVALID_COMMAND:
         s->state = 0;
-        s->out.len = sizeof(imap_invalid_command) - 1;
-        s->out.data = imap_invalid_command;
+        ngx_str_set(&s->out, imap_invalid_command);
         s->mail_state = ngx_imap_start;
         break;
     }
 
     if (tag) {
         if (s->tag.len == 0) {
-            s->tag.len = sizeof(imap_star) - 1;
-            s->tag.data = (u_char *) imap_star;
+            ngx_str_set(&s->tag, imap_star);
         }
 
         if (s->tagged_line.len < s->tag.len + s->text.len + s->out.len) {
@@ -364,24 +357,21 @@ ngx_mail_imap_authenticate(ngx_mail_session_t *s, ngx_connection_t *c)
 
     case NGX_MAIL_AUTH_LOGIN:
 
-        s->out.len = sizeof(imap_username) - 1;
-        s->out.data = imap_username;
+        ngx_str_set(&s->out, imap_username);
         s->mail_state = ngx_imap_auth_login_username;
 
         return NGX_OK;
 
     case NGX_MAIL_AUTH_LOGIN_USERNAME:
 
-        s->out.len = sizeof(imap_password) - 1;
-        s->out.data = imap_password;
+        ngx_str_set(&s->out, imap_password);
         s->mail_state = ngx_imap_auth_login_password;
 
         return ngx_mail_auth_login_username(s, c, 1);
 
     case NGX_MAIL_AUTH_PLAIN:
 
-        s->out.len = sizeof(imap_plain_next) - 1;
-        s->out.data = imap_plain_next;
+        ngx_str_set(&s->out, imap_plain_next);
         s->mail_state = ngx_imap_auth_plain;
 
         return NGX_OK;
diff --git a/src/mail/ngx_mail_pop3_handler.c b/src/mail/ngx_mail_pop3_handler.c
index d22ba5ebf..56726dbcf 100644
--- a/src/mail/ngx_mail_pop3_handler.c
+++ b/src/mail/ngx_mail_pop3_handler.c
@@ -59,8 +59,7 @@ ngx_mail_pop3_init_session(ngx_mail_session_t *s, ngx_connection_t *c)
         s->out.len = p - s->out.data;
 
     } else {
-        s->out.len = sizeof(pop3_greeting) - 1;
-        s->out.data = pop3_greeting;
+        ngx_str_set(&s->out, pop3_greeting);
     }
 
     c->read->handler = ngx_mail_pop3_init_protocol;
@@ -149,8 +148,7 @@ ngx_mail_pop3_auth_state(ngx_event_t *rev)
         return;
     }
 
-    s->out.len = sizeof(pop3_ok) - 1;
-    s->out.data = pop3_ok;
+    ngx_str_set(&s->out, pop3_ok);
 
     if (rc == NGX_OK) {
         switch (s->mail_state) {
@@ -226,8 +224,7 @@ ngx_mail_pop3_auth_state(ngx_event_t *rev)
         case ngx_pop3_auth_login_username:
             rc = ngx_mail_auth_login_username(s, c, 0);
 
-            s->out.len = sizeof(pop3_password) - 1;
-            s->out.data = pop3_password;
+            ngx_str_set(&s->out, pop3_password);
             s->mail_state = ngx_pop3_auth_login_password;
             break;
 
@@ -259,8 +256,7 @@ ngx_mail_pop3_auth_state(ngx_event_t *rev)
         s->mail_state = ngx_pop3_start;
         s->state = 0;
 
-        s->out.len = sizeof(pop3_invalid_command) - 1;
-        s->out.data = pop3_invalid_command;
+        ngx_str_set(&s->out, pop3_invalid_command);
 
         /* fall through */
 
@@ -466,24 +462,21 @@ ngx_mail_pop3_auth(ngx_mail_session_t *s, ngx_connection_t *c)
 
     case NGX_MAIL_AUTH_LOGIN:
 
-        s->out.len = sizeof(pop3_username) - 1;
-        s->out.data = pop3_username;
+        ngx_str_set(&s->out, pop3_username);
         s->mail_state = ngx_pop3_auth_login_username;
 
         return NGX_OK;
 
     case NGX_MAIL_AUTH_LOGIN_USERNAME:
 
-        s->out.len = sizeof(pop3_password) - 1;
-        s->out.data = pop3_password;
+        ngx_str_set(&s->out, pop3_password);
         s->mail_state = ngx_pop3_auth_login_password;
 
         return ngx_mail_auth_login_username(s, c, 1);
 
     case NGX_MAIL_AUTH_PLAIN:
 
-        s->out.len = sizeof(pop3_next) - 1;
-        s->out.data = pop3_next;
+        ngx_str_set(&s->out, pop3_next);
         s->mail_state = ngx_pop3_auth_plain;
 
         return NGX_OK;
diff --git a/src/mail/ngx_mail_proxy_module.c b/src/mail/ngx_mail_proxy_module.c
index a3aa5d50d..a7c4b7e48 100644
--- a/src/mail/ngx_mail_proxy_module.c
+++ b/src/mail/ngx_mail_proxy_module.c
@@ -304,8 +304,7 @@ ngx_mail_proxy_pop3_handler(ngx_event_t *rev)
 
     default:
 #if (NGX_SUPPRESS_WARN)
-        line.len = 0;
-        line.data = NULL;
+        ngx_str_null(&line);
 #endif
         break;
     }
@@ -439,8 +438,7 @@ ngx_mail_proxy_imap_handler(ngx_event_t *rev)
 
     default:
 #if (NGX_SUPPRESS_WARN)
-        line.len = 0;
-        line.data = NULL;
+        ngx_str_null(&line);
 #endif
         break;
     }
@@ -664,8 +662,7 @@ ngx_mail_proxy_smtp_handler(ngx_event_t *rev)
 
     default:
 #if (NGX_SUPPRESS_WARN)
-        line.len = 0;
-        line.data = NULL;
+        ngx_str_null(&line);
 #endif
         break;
     }
diff --git a/src/mail/ngx_mail_smtp_handler.c b/src/mail/ngx_mail_smtp_handler.c
index 0bc422a01..0f69ce968 100644
--- a/src/mail/ngx_mail_smtp_handler.c
+++ b/src/mail/ngx_mail_smtp_handler.c
@@ -319,8 +319,7 @@ ngx_mail_smtp_invalid_pipelining(ngx_event_t *rev)
             return;
         }
 
-        s->out.len = sizeof(smtp_invalid_pipelining) - 1;
-        s->out.data = smtp_invalid_pipelining;
+        ngx_str_set(&s->out, smtp_invalid_pipelining);
     }
 
     ngx_mail_send(c->write);
@@ -414,8 +413,7 @@ ngx_mail_smtp_auth_state(ngx_event_t *rev)
         return;
     }
 
-    s->out.len = sizeof(smtp_ok) - 1;
-    s->out.data = smtp_ok;
+    ngx_str_set(&s->out, smtp_ok);
 
     if (rc == NGX_OK) {
         switch (s->mail_state) {
@@ -435,8 +433,7 @@ ngx_mail_smtp_auth_state(ngx_event_t *rev)
 
             case NGX_SMTP_QUIT:
                 s->quit = 1;
-                s->out.len = sizeof(smtp_bye) - 1;
-                s->out.data = smtp_bye;
+                ngx_str_set(&s->out, smtp_bye);
                 break;
 
             case NGX_SMTP_MAIL:
@@ -456,8 +453,7 @@ ngx_mail_smtp_auth_state(ngx_event_t *rev)
 
             case NGX_SMTP_STARTTLS:
                 rc = ngx_mail_smtp_starttls(s, c);
-                s->out.len = sizeof(smtp_starttls) - 1;
-                s->out.data = smtp_starttls;
+                ngx_str_set(&s->out, smtp_starttls);
                 break;
 
             default:
@@ -470,8 +466,7 @@ ngx_mail_smtp_auth_state(ngx_event_t *rev)
         case ngx_smtp_auth_login_username:
             rc = ngx_mail_auth_login_username(s, c, 0);
 
-            s->out.len = sizeof(smtp_password) - 1;
-            s->out.data = smtp_password;
+            ngx_str_set(&s->out, smtp_password);
             s->mail_state = ngx_smtp_auth_login_password;
             break;
 
@@ -502,9 +497,7 @@ ngx_mail_smtp_auth_state(ngx_event_t *rev)
     case NGX_MAIL_PARSE_INVALID_COMMAND:
         s->mail_state = ngx_smtp_start;
         s->state = 0;
-
-        s->out.len = sizeof(smtp_invalid_command) - 1;
-        s->out.data = smtp_invalid_command;
+        ngx_str_set(&s->out, smtp_invalid_command);
 
         /* fall through */
 
@@ -529,8 +522,7 @@ ngx_mail_smtp_helo(ngx_mail_session_t *s, ngx_connection_t *c)
     ngx_mail_smtp_srv_conf_t  *sscf;
 
     if (s->args.nelts != 1) {
-        s->out.len = sizeof(smtp_invalid_argument) - 1;
-        s->out.data = smtp_invalid_argument;
+        ngx_str_set(&s->out, smtp_invalid_argument);
         s->state = 0;
         return NGX_OK;
     }
@@ -546,10 +538,8 @@ ngx_mail_smtp_helo(ngx_mail_session_t *s, ngx_connection_t *c)
 
     ngx_memcpy(s->smtp_helo.data, arg[0].data, arg[0].len);
 
-    s->smtp_from.len = 0;
-    s->smtp_from.data = NULL;
-    s->smtp_to.len = 0;
-    s->smtp_to.data = NULL;
+    ngx_str_null(&s->smtp_from);
+    ngx_str_null(&s->smtp_to);
 
     sscf = ngx_mail_get_module_srv_conf(s, ngx_mail_smtp_module);
 
@@ -599,8 +589,7 @@ ngx_mail_smtp_auth(ngx_mail_session_t *s, ngx_connection_t *c)
 #endif
 
     if (s->args.nelts == 0) {
-        s->out.len = sizeof(smtp_invalid_argument) - 1;
-        s->out.data = smtp_invalid_argument;
+        ngx_str_set(&s->out, smtp_invalid_argument);
         s->state = 0;
         return NGX_OK;
     }
@@ -611,24 +600,21 @@ ngx_mail_smtp_auth(ngx_mail_session_t *s, ngx_connection_t *c)
 
     case NGX_MAIL_AUTH_LOGIN:
 
-        s->out.len = sizeof(smtp_username) - 1;
-        s->out.data = smtp_username;
+        ngx_str_set(&s->out, smtp_username);
         s->mail_state = ngx_smtp_auth_login_username;
 
         return NGX_OK;
 
     case NGX_MAIL_AUTH_LOGIN_USERNAME:
 
-        s->out.len = sizeof(smtp_password) - 1;
-        s->out.data = smtp_password;
+        ngx_str_set(&s->out, smtp_password);
         s->mail_state = ngx_smtp_auth_login_password;
 
         return ngx_mail_auth_login_username(s, c, 1);
 
     case NGX_MAIL_AUTH_PLAIN:
 
-        s->out.len = sizeof(smtp_next) - 1;
-        s->out.data = smtp_next;
+        ngx_str_set(&s->out, smtp_next);
         s->mail_state = ngx_smtp_auth_plain;
 
         return NGX_OK;
@@ -673,18 +659,14 @@ ngx_mail_smtp_mail(ngx_mail_session_t *s, ngx_connection_t *c)
 
     if (!(sscf->auth_methods & NGX_MAIL_AUTH_NONE_ENABLED)) {
         ngx_mail_smtp_log_rejected_command(s, c, "client was rejected: \"%V\"");
-
-        s->out.len = sizeof(smtp_auth_required) - 1;
-        s->out.data = smtp_auth_required;
-
+        ngx_str_set(&s->out, smtp_auth_required);
         return NGX_OK;
     }
 
     /* auth none */
 
     if (s->smtp_from.len) {
-        s->out.len = sizeof(smtp_bad_sequence) - 1;
-        s->out.data = smtp_bad_sequence;
+        ngx_str_set(&s->out, smtp_bad_sequence);
         return NGX_OK;
     }
 
@@ -723,8 +705,7 @@ ngx_mail_smtp_mail(ngx_mail_session_t *s, ngx_connection_t *c)
     ngx_log_debug1(NGX_LOG_DEBUG_MAIL, c->log, 0,
                    "smtp mail from:\"%V\"", &s->smtp_from);
 
-    s->out.len = sizeof(smtp_ok) - 1;
-    s->out.data = smtp_ok;
+    ngx_str_set(&s->out, smtp_ok);
 
     return NGX_OK;
 }
@@ -738,8 +719,7 @@ ngx_mail_smtp_rcpt(ngx_mail_session_t *s, ngx_connection_t *c)
     ngx_uint_t  i;
 
     if (s->smtp_from.len == 0) {
-        s->out.len = sizeof(smtp_bad_sequence) - 1;
-        s->out.data = smtp_bad_sequence;
+        ngx_str_set(&s->out, smtp_bad_sequence);
         return NGX_OK;
     }
 
@@ -787,13 +767,9 @@ ngx_mail_smtp_rcpt(ngx_mail_session_t *s, ngx_connection_t *c)
 static ngx_int_t
 ngx_mail_smtp_rset(ngx_mail_session_t *s, ngx_connection_t *c)
 {
-    s->smtp_from.len = 0;
-    s->smtp_from.data = NULL;
-    s->smtp_to.len = 0;
-    s->smtp_to.data = NULL;
-
-    s->out.len = sizeof(smtp_ok) - 1;
-    s->out.data = smtp_ok;
+    ngx_str_null(&s->smtp_from);
+    ngx_str_null(&s->smtp_to);
+    ngx_str_set(&s->out, smtp_ok);
 
     return NGX_OK;
 }
@@ -814,12 +790,9 @@ ngx_mail_smtp_starttls(ngx_mail_session_t *s, ngx_connection_t *c)
              * obtained from client before STARTTLS.
              */
 
-            s->smtp_helo.len = 0;
-            s->smtp_helo.data = NULL;
-            s->smtp_from.len = 0;
-            s->smtp_from.data = NULL;
-            s->smtp_to.len = 0;
-            s->smtp_to.data = NULL;
+            ngx_str_null(&s->smtp_helo);
+            ngx_str_null(&s->smtp_from);
+            ngx_str_null(&s->smtp_to);
 
             c->read->handler = ngx_mail_starttls_handler;
             return NGX_OK;
diff --git a/src/mail/ngx_mail_ssl_module.c b/src/mail/ngx_mail_ssl_module.c
index 90f2b1b2b..de463e96b 100644
--- a/src/mail/ngx_mail_ssl_module.c
+++ b/src/mail/ngx_mail_ssl_module.c
@@ -163,8 +163,7 @@ ngx_mail_ssl_create_conf(ngx_conf_t *cf)
      *     scf->certificate = { 0, NULL };
      *     scf->certificate_key = { 0, NULL };
      *     scf->dhparam = { 0, NULL };
-     *     scf->ciphers.len = 0;
-     *     scf->ciphers.data = NULL;
+     *     scf->ciphers = { 0, NULL };
      *     scf->shm_zone = NULL;
      */