--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwlib/lw_strpool.c	Mon Aug 05 21:27:09 2019 -0600
@@ -0,0 +1,71 @@
+/*
+lwlib/lw_strpool.c
+
+Copyright © 2013 William Astle
+
+This file is part of LWTOOLS.
+
+LWTOOLS 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 of the License, 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. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include <stdlib.h>
+#include <string.h>
+
+#include "lw_alloc.h"
+#include "lw_string.h"
+#include "lw_strpool.h"
+
+struct lw_strpool *lw_strpool_create(void)
+{
+	struct lw_strpool *sp;
+	
+	sp = lw_alloc(sizeof(struct lw_strpool));
+	sp -> nstrs = 0;
+	sp -> strs = NULL;
+	return sp;
+}
+
+extern void lw_strpool_free(struct lw_strpool *sp)
+{
+	int i;
+	
+	for (i = 0; i < sp -> nstrs; i++)
+		lw_free(sp -> strs[i]);
+	lw_free(sp -> strs);
+	lw_free(sp);
+}
+
+char *lw_strpool_strdup(struct lw_strpool *sp, const char *s)
+{
+	int i;
+	
+	if (!s)
+		return NULL;
+
+	/* first do a fast scan for a pointer match */	
+	for (i = 0; i < sp -> nstrs; i++)
+		if (sp -> strs[i] == s)
+			return sp -> strs[i];
+	
+	/* no match - do a slow scan for a string match */
+	for (i = 0; i < sp -> nstrs; i++)
+		if (strcmp(sp -> strs[i], s) == 0)
+			return sp -> strs[i];
+	
+	/* no match - create a new string entry */
+	sp -> strs = lw_realloc(sp -> strs, sizeof(char *) * (sp -> nstrs + 1));
+	sp -> strs[sp -> nstrs] = lw_strdup(s);
+	sp -> nstrs++;
+	return sp -> strs[sp -> nstrs - 1];
+}