--- /dev/null
+/* Keeping a unique copy of strings.
+ Copyright (C) 2002 Free Software Foundation, Inc.
+
+ This file is part of Bison, the GNU Compiler Compiler.
+
+ Bison 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 2, or (at your option)
+ any later version.
+
+ Bison 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 Bison; see the file COPYING. If not, write to
+ the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA. */
+
+#include "system.h"
+
+#include <error.h>
+#include <hash.h>
+#include <quotearg.h>
+
+#include "uniqstr.h"
+
+/*-----------------------.
+| A uniqstr hash table. |
+`-----------------------*/
+
+/* Initial capacity of uniqstr hash table. */
+#define HT_INITIAL_CAPACITY 257
+
+static struct hash_table *uniqstrs_table = NULL;
+
+/*-------------------------------------.
+| Create the uniqstr for S if needed. |
+`-------------------------------------*/
+
+uniqstr
+uniqstr_new (const char *s)
+{
+ uniqstr res = hash_lookup (uniqstrs_table, s);
+ if (!res)
+ {
+ /* First insertion in the hash. */
+ res = xstrdup (s);
+ hash_insert (uniqstrs_table, res);
+ }
+ return res;
+}
+
+
+/*------------------------------.
+| Abort if S is not a uniqstr. |
+`------------------------------*/
+
+void
+uniqstr_assert (const char *s)
+{
+ if (!hash_lookup (uniqstrs_table, s))
+ {
+ error (0, 0, "not a uniqstr: %s", quotearg (s));
+ abort ();
+ }
+}
+
+
+/*--------------------.
+| Print the uniqstr. |
+`--------------------*/
+
+static bool
+uniqstr_print (const uniqstr s)
+{
+ fprintf (stderr, "%s\n", s);
+ return true;
+}
+
+\f
+/*-----------------------.
+| A uniqstr hash table. |
+`-----------------------*/
+
+static bool
+hash_compare_uniqstr (const uniqstr m1, const uniqstr m2)
+{
+ return strcmp (m1, m2) == 0;
+}
+
+static unsigned int
+hash_uniqstr (const uniqstr m, unsigned int tablesize)
+{
+ return hash_string (m, tablesize);
+}
+
+/* A function to apply to each symbol. */
+typedef bool (*uniqstr_processor) (const uniqstr);
+
+/*----------------------------.
+| Create the uniqstrs table. |
+`----------------------------*/
+
+void
+uniqstrs_new (void)
+{
+ uniqstrs_table = hash_initialize (HT_INITIAL_CAPACITY,
+ NULL,
+ (Hash_hasher) hash_uniqstr,
+ (Hash_comparator) hash_compare_uniqstr,
+ (Hash_data_freer) free);
+}
+
+
+/*-------------------------------------.
+| Perform a task on all the uniqstrs. |
+`-------------------------------------*/
+
+static void
+uniqstrs_do (uniqstr_processor processor, void *processor_data)
+{
+ hash_do_for_each (uniqstrs_table,
+ (Hash_processor) processor,
+ processor_data);
+}
+
+
+/*-----------------.
+| Print them all. |
+`-----------------*/
+
+void
+uniqstrs_print (void)
+{
+ uniqstrs_do (uniqstr_print, NULL);
+}
+
+
+/*--------------------.
+| Free the uniqstrs. |
+`--------------------*/
+
+void
+uniqstrs_free (void)
+{
+ hash_free (uniqstrs_table);
+}
--- /dev/null
+/* Keeping a unique copy of strings.
+ Copyright (C) 2002 Free Software Foundation, Inc.
+
+ This file is part of Bison, the GNU Compiler Compiler.
+
+ Bison 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 2, or (at your option)
+ any later version.
+
+ Bison 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 Bison; see the file COPYING. If not, write to
+ the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA. */
+
+#ifndef UNIQSTR_H_
+# define UNIQSTR_H_
+
+/*-----------------------------------------.
+| Pointers to unique copies of C strings. |
+`-----------------------------------------*/
+
+typedef char const *uniqstr;
+
+/* Return the uniqstr for S. */
+uniqstr uniqstr_new (char const *s);
+
+/* Two uniqstr have the same value iff they are the same. */
+#define UNIQSTR_EQ(S1, S2) ((S1) == (S2))
+
+/*--------------------------------------.
+| Initializing, destroying, debugging. |
+`--------------------------------------*/
+
+/* Create the string table. */
+void uniqstrs_new (void);
+
+/* Die if S is not a uniqstr. */
+void uniqstr_assert (const char *s);
+
+/* Free all the memory allocated for symbols. */
+void uniqstrs_free (void);
+
+/* Report them all. */
+void uniqstrs_print (void);
+
+#endif /* ! defined UNIQSTR_H_ */