1 files changed, 98 insertions, 0 deletions
diff --git a/lib/fieldtrie.c b/lib/fieldtrie.c
new file mode 100644
index 0000000..250fc89
--- /dev/null
+++ b/lib/fieldtrie.c
@@ -0,0 +1,98 @@
+/*  dctrl-tools - Debian control file inspection tools
+    Copyright (C) 2003 Antti-Juhani Kaijanaho
+
+    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 2 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, write to the Free Software
+    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <assert.h>
+#include <ctype.h>
+#include <string.h>
+#include "fieldtrie.h"
+#include "msg.h"
+
+struct field_bucket {
+	char const * name;
+	size_t namelen;
+	struct field_attr attr;
+	struct field_bucket * next;
+};
+
+struct fieldtrie_private {
+	size_t nextfree;
+	/* A one-level trie listing all field names occurring in the
+	 * atomic predicates. */
+	struct field_bucket * fields[UCHAR_MAX];
+};
+
+static struct fieldtrie_private trie;
+
+void fieldtrie_init(void)
+{
+	for (size_t i = 0; i < UCHAR_MAX; i++) {
+		trie.fields[i] = 0;
+	}
+	trie.nextfree = 0;
+}
+
+size_t fieldtrie_insert(char const * s)
+{
+	size_t slen = strlen(s);
+	struct field_attr l_attr = fieldtrie_lookup(s, slen);
+	if (l_attr.valid) return l_attr.inx;
+	struct field_bucket * b = malloc(sizeof *b);
+	if (b == 0) fatal_enomem(0);
+	b->name = malloc(slen+1);
+	if (b->name == 0) fatal_enomem(0);
+	strcpy((char*)b->name, s);
+	b->namelen = slen;
+	b->attr.inx = trie.nextfree++;
+	b->attr.valid = true;
+	unsigned char c = tolower((unsigned char)(b->name[0]));
+	b->next = trie.fields[c];
+	trie.fields[c] = b;
+	return b->attr.inx;
+}
+
+struct field_attr fieldtrie_lookup(char const * s, size_t n)
+{
+	for (struct field_bucket * b = trie.fields[tolower((unsigned char)s[0])];
+	     b != 0;
+	     b = b->next) {
+		if (n == b->namelen &&
+		    strncasecmp(s, b->name, n) == 0) return b->attr;
+	}
+	return (struct field_attr){ .valid = false };
+}
+
+size_t fieldtrie_count(void)
+{
+	return trie.nextfree;
+}
+
+#if 0
+void fieldtrie_clear(void)
+{
+	for (size_t i = 0; i < UCHAR_MAX; i++) {
+		struct field_bucket * b = trie.fields[i];
+		while (b != 0) {
+			struct field_bucket * bn = b->next;
+			free(b);
+			b = bn;
+		}
+		trie->fields[i] = 0;
+	}
+	trie->nextfree = 0;
+}
+#endif