Add "pkey_sequence" attribute (in addition to "pkey") to layer config.

In order to insert new feature into layer based on PostgreSQL view,
"pkey" attribute is not enough: one should be able to deduce sequence
name using pg_get_serial_sequence() function, which returns empty row
for views. Fix this by adding "pkey_sequence" attribute.

src/ows/ows_config.c

@@ -567,6 +567,16 @@ static void ows_parse_config_layer(ows * o, xmlTextReaderPtr r)
     buffer_copy(layer->pkey, layer->parent->pkey);
   }
 
+  a = xmlTextReaderGetAttribute(r, (xmlChar *) "pkey_sequence");
+  if (a) {
+    layer->pkey_sequence = buffer_init();
+    buffer_add_str(layer->pkey_sequence, (char *) a);
+    xmlFree(a);
+  } else if (layer->parent && layer->parent->pkey_sequence) {
+    layer->pkey_sequence = buffer_init();
+    buffer_copy(layer->pkey_sequence, layer->parent->pkey_sequence);
+  }
+
   if (layer->name && layer->ns_uri) {
       buffer_add_head(layer->name, ':');
       buffer_add_head_str(layer->name, layer->ns_uri->buf);

src/ows/ows_layer.c

@@ -534,6 +534,7 @@ ows_layer *ows_layer_init()
   l->exclude_items = NULL;
   l->include_items = NULL;
   l->pkey = NULL;
+  l->pkey_sequence = NULL;
   l->ns_prefix = buffer_init();
   l->ns_uri = buffer_init();
   l->storage = ows_layer_storage_init();
@@ -564,6 +565,7 @@ void ows_layer_free(ows_layer * l)
   if (l->exclude_items) list_free(l->exclude_items);
   if (l->include_items) list_free(l->include_items);
   if (l->pkey)          buffer_free(l->pkey);
+  if (l->pkey_sequence) buffer_free(l->pkey_sequence);
 
   free(l);
   l = NULL;

src/ows/ows_storage.c

@@ -268,9 +268,13 @@ static void ows_storage_fill_pkey(ows * o, ows_layer * l)
     /* Even if no sequence found, this function return an empty row
      * so we must check that result string returned > 0 char
      */
-    if (PQntuples(res) == 1 && strlen((char *) PQgetvalue(res, 0, 0)) > 0) {
+    if ( l->pkey_sequence ||
+         (PQntuples(res) == 1 && strlen((char *) PQgetvalue(res, 0, 0)) > 0) ) {
       l->storage->pkey_sequence = buffer_init();
-      buffer_add_str(l->storage->pkey_sequence, PQgetvalue(res, 0, 0));
+      if ( l->pkey_sequence )
+        buffer_copy(l->storage->pkey_sequence, l->pkey_sequence);
+      else
+        buffer_add_str(l->storage->pkey_sequence, PQgetvalue(res, 0, 0));
     }
 
     buffer_empty(sql);

src/ows_struct.h

@@ -179,6 +179,7 @@ typedef struct Ows_layer {
   list * exclude_items;
   list * include_items;
   buffer * pkey;
+  buffer * pkey_sequence;
   list * gml_ns;
   buffer * ns_prefix;
   buffer * ns_uri;