1 files changed, 361 insertions, 0 deletions

diff --git a/src/vnet/config.c b/src/vnet/config.c
new file mode 100644
index 00000000000..03189d77cd5
--- /dev/null
+++ b/src/vnet/config.c
@@ -0,0 +1,361 @@
+/*
+ * Copyright (c) 2015 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+/*
+ * config.c: feature configuration
+ *
+ * Copyright (c) 2008 Eliot Dresselhaus
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ *  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ *  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ *  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ *  LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ *  OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ *  WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#include <vnet/vnet.h>
+
+static vnet_config_feature_t *
+duplicate_feature_vector (vnet_config_feature_t * feature_vector)
+{
+  vnet_config_feature_t *result, *f;
+
+  result = vec_dup (feature_vector);
+  vec_foreach (f, result) f->feature_config = vec_dup (f->feature_config);
+
+  return result;
+}
+
+static void
+free_feature_vector (vnet_config_feature_t * feature_vector)
+{
+  vnet_config_feature_t *f;
+
+  vec_foreach (f, feature_vector) vnet_config_feature_free (f);
+  vec_free (feature_vector);
+}
+
+static u32
+add_next (vlib_main_t * vm,
+	  vnet_config_main_t * cm, u32 last_node_index, u32 this_node_index)
+{
+  u32 i, ni = ~0;
+
+  if (last_node_index != ~0)
+    return vlib_node_add_next (vm, last_node_index, this_node_index);
+
+  for (i = 0; i < vec_len (cm->start_node_indices); i++)
+    {
+      u32 tmp;
+      tmp =
+	vlib_node_add_next (vm, cm->start_node_indices[i], this_node_index);
+      if (ni == ~0)
+	ni = tmp;
+      /* Start nodes to first must agree on next indices. */
+      ASSERT (ni == tmp);
+    }
+
+  return ni;
+}
+
+static vnet_config_t *
+find_config_with_features (vlib_main_t * vm,
+			   vnet_config_main_t * cm,
+			   vnet_config_feature_t * feature_vector)
+{
+  u32 last_node_index = ~0;
+  vnet_config_feature_t *f;
+  u32 *config_string;
+  uword *p;
+  vnet_config_t *c;
+
+  config_string = cm->config_string_temp;
+  cm->config_string_temp = 0;
+  if (config_string)
+    _vec_len (config_string) = 0;
+
+  vec_foreach (f, feature_vector)
+  {
+    /* Connect node graph. */
+    f->next_index = add_next (vm, cm, last_node_index, f->node_index);
+    last_node_index = f->node_index;
+
+    /* Store next index in config string. */
+    vec_add1 (config_string, f->next_index);
+
+    /* Store feature config. */
+    vec_add (config_string, f->feature_config, vec_len (f->feature_config));
+  }
+
+  /* Terminate config string with next for end node. */
+  if (last_node_index == ~0 || last_node_index != cm->end_node_index)
+    {
+      u32 next_index = add_next (vm, cm, last_node_index, cm->end_node_index);
+      vec_add1 (config_string, next_index);
+    }
+
+  /* See if config string is unique. */
+  p = hash_get_mem (cm->config_string_hash, config_string);
+  if (p)
+    {
+      /* Not unique.  Share existing config. */
+      cm->config_string_temp = config_string;	/* we'll use it again later. */
+      free_feature_vector (feature_vector);
+      c = pool_elt_at_index (cm->config_pool, p[0]);
+    }
+  else
+    {
+      u32 *d;
+
+      pool_get (cm->config_pool, c);
+      c->index = c - cm->config_pool;
+      c->features = feature_vector;
+      c->config_string_vector = config_string;
+
+      /* Allocate copy of config string in heap.
+         VLIB buffers will maintain pointers to heap as they read out
+         configuration data. */
+      c->config_string_heap_index
+	= heap_alloc (cm->config_string_heap, vec_len (config_string) + 1,
+		      c->config_string_heap_handle);
+
+      /* First element in heap points back to pool index. */
+      d =
+	vec_elt_at_index (cm->config_string_heap,
+			  c->config_string_heap_index);
+      d[0] = c->index;
+      clib_memcpy (d + 1, config_string, vec_bytes (config_string));
+      hash_set_mem (cm->config_string_hash, config_string, c->index);
+
+      c->reference_count = 0;	/* will be incremented by caller. */
+    }
+
+  return c;
+}
+
+void
+vnet_config_init (vlib_main_t * vm,
+		  vnet_config_main_t * cm,
+		  char *start_node_names[],
+		  int n_start_node_names,
+		  char *feature_node_names[], int n_feature_node_names)
+{
+  vlib_node_t *n;
+  u32 i;
+
+  memset (cm, 0, sizeof (cm[0]));
+
+  cm->config_string_hash =
+    hash_create_vec (0,
+		     STRUCT_SIZE_OF (vnet_config_t, config_string_vector[0]),
+		     sizeof (uword));
+
+  ASSERT (n_feature_node_names >= 1);
+
+  vec_resize (cm->start_node_indices, n_start_node_names);
+  for (i = 0; i < n_start_node_names; i++)
+    {
+      n = vlib_get_node_by_name (vm, (u8 *) start_node_names[i]);
+      /* Given node name must exist. */
+      ASSERT (n != 0);
+      cm->start_node_indices[i] = n->index;
+    }
+
+  vec_resize (cm->node_index_by_feature_index, n_feature_node_names);
+  for (i = 0; i < n_feature_node_names; i++)
+    {
+      if (!feature_node_names[i])
+	cm->node_index_by_feature_index[i] = ~0;
+      else
+	{
+	  n = vlib_get_node_by_name (vm, (u8 *) feature_node_names[i]);
+	  /* Given node may exist in plug-in library which is not present */
+	  if (n)
+	    {
+	      if (i + 1 == n_feature_node_names)
+		cm->end_node_index = n->index;
+	      cm->node_index_by_feature_index[i] = n->index;
+	    }
+	  else
+	    cm->node_index_by_feature_index[i] = ~0;
+	}
+    }
+}
+
+static void
+remove_reference (vnet_config_main_t * cm, vnet_config_t * c)
+{
+  ASSERT (c->reference_count > 0);
+  c->reference_count -= 1;
+  if (c->reference_count == 0)
+    {
+      hash_unset (cm->config_string_hash, c->config_string_vector);
+      vnet_config_free (cm, c);
+      pool_put (cm->config_pool, c);
+    }
+}
+
+static int
+feature_cmp (void *a1, void *a2)
+{
+  vnet_config_feature_t *f1 = a1;
+  vnet_config_feature_t *f2 = a2;
+
+  return (int) f1->feature_index - f2->feature_index;
+}
+
+always_inline u32 *
+vnet_get_config_heap (vnet_config_main_t * cm, u32 ci)
+{
+  return heap_elt_at_index (cm->config_string_heap, ci);
+}
+
+u32
+vnet_config_add_feature (vlib_main_t * vm,
+			 vnet_config_main_t * cm,
+			 u32 config_string_heap_index,
+			 u32 feature_index,
+			 void *feature_config, u32 n_feature_config_bytes)
+{
+  vnet_config_t *old, *new;
+  vnet_config_feature_t *new_features, *f;
+  u32 n_feature_config_u32s;
+  u32 node_index = vec_elt (cm->node_index_by_feature_index, feature_index);
+
+  if (node_index == ~0)		// feature node does not exist
+    return config_string_heap_index;	// return original config index
+
+  if (config_string_heap_index == ~0)
+    {
+      old = 0;
+      new_features = 0;
+    }
+  else
+    {
+      u32 *p = vnet_get_config_heap (cm, config_string_heap_index);
+      old = pool_elt_at_index (cm->config_pool, p[-1]);
+      new_features = old->features;
+      if (new_features)
+	new_features = duplicate_feature_vector (new_features);
+    }
+
+  vec_add2 (new_features, f, 1);
+  f->feature_index = feature_index;
+  f->node_index = node_index;
+
+  n_feature_config_u32s =
+    round_pow2 (n_feature_config_bytes,
+		sizeof (f->feature_config[0])) /
+    sizeof (f->feature_config[0]);
+  vec_add (f->feature_config, feature_config, n_feature_config_u32s);
+
+  /* Sort (prioritize) features. */
+  if (vec_len (new_features) > 1)
+    vec_sort_with_function (new_features, feature_cmp);
+
+  if (old)
+    remove_reference (cm, old);
+
+  new = find_config_with_features (vm, cm, new_features);
+  new->reference_count += 1;
+
+  /*
+   * User gets pointer to config string first element
+   * (which defines the pool index
+   * this config string comes from).
+   */
+  vec_validate (cm->config_pool_index_by_user_index,
+		new->config_string_heap_index + 1);
+  cm->config_pool_index_by_user_index[new->config_string_heap_index + 1]
+    = new - cm->config_pool;
+  return new->config_string_heap_index + 1;
+}
+
+u32
+vnet_config_del_feature (vlib_main_t * vm,
+			 vnet_config_main_t * cm,
+			 u32 config_string_heap_index,
+			 u32 feature_index,
+			 void *feature_config, u32 n_feature_config_bytes)
+{
+  vnet_config_t *old, *new;
+  vnet_config_feature_t *new_features, *f;
+  u32 n_feature_config_u32s;
+
+  {
+    u32 *p = vnet_get_config_heap (cm, config_string_heap_index);
+
+    old = pool_elt_at_index (cm->config_pool, p[-1]);
+  }
+
+  n_feature_config_u32s =
+    round_pow2 (n_feature_config_bytes,
+		sizeof (f->feature_config[0])) /
+    sizeof (f->feature_config[0]);
+
+  /* Find feature with same index and opaque data. */
+  vec_foreach (f, old->features)
+  {
+    if (f->feature_index == feature_index
+	&& vec_len (f->feature_config) == n_feature_config_u32s
+	&& (n_feature_config_u32s == 0
+	    || !memcmp (f->feature_config, feature_config,
+			n_feature_config_bytes)))
+      break;
+  }
+
+  /* Feature not found. */
+  if (f >= vec_end (old->features))
+    return config_string_heap_index;	// return original config index
+
+  new_features = duplicate_feature_vector (old->features);
+  f = new_features + (f - old->features);
+  vnet_config_feature_free (f);
+  vec_delete (new_features, 1, f - new_features);
+
+  /* must remove old from config_pool now as it may be expanded and change
+     memory location if the following function find_config_with_features()
+     adds a new config because none of existing config's has matching features
+     and so can be reused */
+  remove_reference (cm, old);
+  new = find_config_with_features (vm, cm, new_features);
+  new->reference_count += 1;
+
+  vec_validate (cm->config_pool_index_by_user_index,
+		new->config_string_heap_index + 1);
+  cm->config_pool_index_by_user_index[new->config_string_heap_index + 1]
+    = new - cm->config_pool;
+  return new->config_string_heap_index + 1;
+}
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */