1 files changed, 104 insertions, 0 deletions
diff --git a/libcpp/include/symtab.h b/libcpp/include/symtab.h
new file mode 100644
index 000000000..4107a6f8a
--- /dev/null
+++ b/libcpp/include/symtab.h
@@ -0,0 +1,104 @@
+/* Hash tables.
+   Copyright (C) 2000, 2001, 2003, 2004, 2007, 2008, 2009, 2010
+   Free Software Foundation, Inc.
+
+This program 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.
+
+This program 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 this program; see the file COPYING3.  If not see
+<http://www.gnu.org/licenses/>.  */
+
+#ifndef LIBCPP_SYMTAB_H
+#define LIBCPP_SYMTAB_H
+
+#include "obstack.h"
+
+#ifndef GTY
+#define GTY(x) /* nothing */
+#endif
+
+/* This is what each hash table entry points to.  It may be embedded
+   deeply within another object.  */
+typedef struct ht_identifier ht_identifier;
+typedef struct ht_identifier *ht_identifier_ptr;
+struct GTY(()) ht_identifier {
+  const unsigned char *str;
+  unsigned int len;
+  unsigned int hash_value;
+};
+
+#define HT_LEN(NODE) ((NODE)->len)
+#define HT_STR(NODE) ((NODE)->str)
+
+typedef struct ht hash_table;
+typedef struct ht_identifier *hashnode;
+
+enum ht_lookup_option {HT_NO_INSERT = 0, HT_ALLOC};
+
+/* An identifier hash table for cpplib and the front ends.  */
+struct ht
+{
+  /* Identifiers are allocated from here.  */
+  struct obstack stack;
+
+  hashnode *entries;
+  /* Call back, allocate a node.  */
+  hashnode (*alloc_node) (hash_table *);
+  /* Call back, allocate something that hangs off a node like a cpp_macro.  
+     NULL means use the usual allocator.  */
+  void * (*alloc_subobject) (size_t);
+
+  unsigned int nslots;		/* Total slots in the entries array.  */
+  unsigned int nelements;	/* Number of live elements.  */
+
+  /* Link to reader, if any.  For the benefit of cpplib.  */
+  struct cpp_reader *pfile;
+
+  /* Table usage statistics.  */
+  unsigned int searches;
+  unsigned int collisions;
+
+  /* Should 'entries' be freed when it is no longer needed?  */
+  bool entries_owned;
+};
+
+/* Initialize the hashtable with 2 ^ order entries.  */
+extern hash_table *ht_create (unsigned int order);
+
+/* Frees all memory associated with a hash table.  */
+extern void ht_destroy (hash_table *);
+
+extern hashnode ht_lookup (hash_table *, const unsigned char *,
+			   size_t, enum ht_lookup_option);
+extern hashnode ht_lookup_with_hash (hash_table *, const unsigned char *,
+                                     size_t, unsigned int,
+                                     enum ht_lookup_option);
+#define HT_HASHSTEP(r, c) ((r) * 67 + ((c) - 113));
+#define HT_HASHFINISH(r, len) ((r) + (len))
+
+/* For all nodes in TABLE, make a callback.  The callback takes
+   TABLE->PFILE, the node, and a PTR, and the callback sequence stops
+   if the callback returns zero.  */
+typedef int (*ht_cb) (struct cpp_reader *, hashnode, const void *);
+extern void ht_forall (hash_table *, ht_cb, const void *);
+
+/* For all nodes in TABLE, call the callback.  If the callback returns
+   a nonzero value, the node is removed from the table.  */
+extern void ht_purge (hash_table *, ht_cb, const void *);
+
+/* Restore the hash table.  */
+extern void ht_load (hash_table *ht, hashnode *entries,
+		     unsigned int nslots, unsigned int nelements, bool own);
+
+/* Dump allocation statistics to stderr.  */
+extern void ht_dump_statistics (hash_table *);
+
+#endif /* LIBCPP_SYMTAB_H */