- move mesh regex block code to a lib

1 files changed, 131 insertions, 0 deletions

diff --git a/src/mesh/mesh_block_lib.c b/src/mesh/mesh_block_lib.c
new file mode 100644
index 000000000..e56aa5725
--- /dev/null
+++ b/src/mesh/mesh_block_lib.c
@@ -0,0 +1,131 @@
+/*
+     This file is part of GNUnet.
+     (C) 2001 - 2011 Christian Grothoff (and other contributing authors)
+
+     GNUnet is free software; you can redistribute it and/or modify
+     it under the terms of the GNU General Public License as published
+     by the Free Software Foundation; either version 3, or (at your
+     option) any later version.
+
+     GNUnet is distributed in the hope that it will be useful, but
+     WITHOUT ANY WARRANTY; without even the implied warranty of
+     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+     General Public License for more details.
+
+     You should have received a copy of the GNU General Public License
+     along with GNUnet; see the file COPYING.  If not, write to the
+     Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+     Boston, MA 02111-1307, USA.
+*/
+
+/**
+ * @author Bartlomiej Polot
+ * @file mesh/mesh_block_lib.c
+ */
+
+#ifdef __cplusplus
+extern "C"
+{
+#if 0
+  /* keep Emacsens' auto-indent happy */
+}
+#endif
+#endif
+
+#include "mesh_block_lib.h"
+
+/**
+ * Iterator over edges in a block.
+ *
+ * @param cls Closure.
+ * @param token Token that follows to next state.
+ * @param len Lenght of token.
+ * @param key Hash of next state.
+ */
+static int
+check_edge (void *cls,
+            const char *token,
+            size_t len,
+            const struct GNUNET_HashCode *key)
+{
+  return GNUNET_YES;
+}
+
+
+/**
+ * Check if the regex block is well formed, including all edges
+ *
+ * @param block The start of the block.
+ * @param size The size of the block.
+ *
+ * @return GNUNET_OK in case it's fine, GNUNET_SYSERR otherwise.
+ */
+int
+GNUNET_MESH_regex_block_check (const struct MeshRegexBlock *block,
+                               size_t size)
+{
+  return GNUNET_MESH_regex_block_iterate(NULL, block, size, &check_edge);
+}
+
+
+/**
+ * Iterate over all edges of a block of a regex state.
+ *
+ * @param cls Closure for the iterator.
+ * @param block Block to iterate over.
+ * @param size Size of block.
+ * @param iterator Function to call on each edge in the block.
+ *
+ * @return How many bytes of block have been processed
+ */
+int
+GNUNET_MESH_regex_block_iterate (void *cls,
+                                 const struct MeshRegexBlock *block,
+                                 size_t size,
+                                 GNUNET_MESH_EgdeIterator iterator)
+{
+  struct MeshRegexEdge *edge;
+  unsigned int n;
+  unsigned int n_token;
+  unsigned int i;
+  size_t offset;
+  char *aux;
+
+  offset = sizeof (struct MeshRegexBlock);
+  if (offset > size) // Is it safe to access the regex block?
+    return GNUNET_SYSERR;
+  n = ntohl (block->n_proof);
+  offset =+ n;
+  if (offset > size) // Is it safe to access the regex proof?
+    return GNUNET_SYSERR;
+  aux = (char *) &block[1];  // Skip regex block
+  aux = &aux[n];             // Skip regex proof
+  n = ntohl (block->n_edges);
+  for (i = 0; i < n; n++) // aux always points at the end of the previous block
+  {
+    offset += sizeof (struct MeshRegexEdge);
+    if (offset > size) // Is it safe to access the next edge block?
+      return GNUNET_SYSERR;
+    edge = (struct MeshRegexEdge *) aux;
+    n_token = ntohl (edge->n_token);
+    offset += n_token;
+    if (offset > size) // Is it safe to access the edge token?
+      return GNUNET_SYSERR;
+    aux = (char *) &edge[1]; // Skip edge block
+    if (NULL != iterator)
+        if (GNUNET_NO == iterator (cls, aux, n_token, &edge->key))
+            return GNUNET_OK;
+    aux = &aux[n_token];     // Skip edge token
+  }
+  // The total size should be exactly the size of (regex + all edges) blocks
+  return (offset == size) ? GNUNET_OK : GNUNET_SYSERR;
+}
+
+#if 0                           /* keep Emacsens' auto-indent happy */
+{
+#endif
+#ifdef __cplusplus
+}
+#endif
+
+/* end of mesh_protocol.h */