Added r->schema. For HTTP/1, it keeps scheme from the absolute form of URI. For HTTP/2, the :scheme request pseudo-header field value.

diff --git a/src/http/ngx_http_core_module.c b/src/http/ngx_http_core_module.c
index 2d8fdb8..c57ec00 100644
--- a/src/http/ngx_http_core_module.c
+++ b/src/http/ngx_http_core_module.c

@@ -2318,6 +2318,7 @@
     sr->unparsed_uri = r->unparsed_uri;
     sr->method_name = ngx_http_core_get_method;
     sr->http_protocol = r->http_protocol;
+    sr->schema = r->schema;
 
     ngx_http_set_exten(sr);
 

diff --git a/src/http/ngx_http_request.c b/src/http/ngx_http_request.c
index 210994b..0432c91 100644
--- a/src/http/ngx_http_request.c
+++ b/src/http/ngx_http_request.c

@@ -987,6 +987,11 @@
                 return;
             }
 
+            if (r->schema_end) {
+                r->schema.len = r->schema_end - r->schema_start;
+                r->schema.data = r->schema_start;
+            }
+
             if (r->host_end) {
 
                 host.len = r->host_end - r->host_start;

diff --git a/src/http/ngx_http_request.h b/src/http/ngx_http_request.h
index 39baa0f..6bfff96 100644
--- a/src/http/ngx_http_request.h
+++ b/src/http/ngx_http_request.h

@@ -412,6 +412,7 @@
 
     ngx_str_t                         method_name;
     ngx_str_t                         http_protocol;
+    ngx_str_t                         schema;
 
     ngx_chain_t                      *out;
     ngx_http_request_t               *main;

diff --git a/src/http/v2/ngx_http_v2.c b/src/http/v2/ngx_http_v2.c
index a35140c..d3fdf05 100644
--- a/src/http/v2/ngx_http_v2.c
+++ b/src/http/v2/ngx_http_v2.c

@@ -2616,16 +2616,14 @@
     r->method_name = ngx_http_core_get_method;
     r->method = NGX_HTTP_GET;
 
-    r->schema_start = (u_char *) "https";
-
 #if (NGX_HTTP_SSL)
     if (fc->ssl) {
-        r->schema_end = r->schema_start + 5;
+        ngx_str_set(&r->schema, "https");
 
     } else
 #endif
     {
-        r->schema_end = r->schema_start + 4;
+        ngx_str_set(&r->schema, "http");
     }
 
     value.data = ngx_pstrdup(pool, path);
@@ -3477,7 +3475,7 @@
     u_char      c, ch;
     ngx_uint_t  i;
 
-    if (r->schema_start) {
+    if (r->schema.len) {
         ngx_log_error(NGX_LOG_INFO, r->connection->log, 0,
                       "client sent duplicate :scheme header");
 
@@ -3511,8 +3509,7 @@
         return NGX_DECLINED;
     }
 
-    r->schema_start = value->data;
-    r->schema_end = value->data + value->len;
+    r->schema = *value;
 
     return NGX_OK;
 }
@@ -3575,14 +3572,14 @@
     static const u_char ending[] = " HTTP/2.0";
 
     if (r->method_name.len == 0
-        || r->schema_start == NULL
+        || r->schema.len == 0
         || r->unparsed_uri.len == 0)
     {
         if (r->method_name.len == 0) {
             ngx_log_error(NGX_LOG_INFO, r->connection->log, 0,
                           "client sent no :method header");
 
-        } else if (r->schema_start == NULL) {
+        } else if (r->schema.len == 0) {
             ngx_log_error(NGX_LOG_INFO, r->connection->log, 0,
                           "client sent no :scheme header");