add parser helpers similar to the blobmsg parser in libubox

1 files changed, 130 insertions, 0 deletions

diff --git a/parse.c b/parse.c
new file mode 100644
index 0000000..d0684f9
--- /dev/null
+++ b/parse.c
@@ -0,0 +1,130 @@
+/*
+ * libuci - Library for the Unified Configuration Interface
+ * Copyright (C) 2008 Felix Fietkau <nbd@openwrt.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1
+ * as published by the Free Software Foundation
+ *
+ * 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.
+ */
+
+#include <string.h>
+#include <stdint.h>
+
+#include "uci.h"
+
+void uci_parse_section(struct uci_section *s, struct uci_parse_option *opts,
+		       int n_opts, struct uci_option **tb)
+{
+	struct uci_element *e;
+
+	memset(tb, 0, n_opts * sizeof(*tb));
+
+	uci_foreach_element(&s->options, e) {
+		struct uci_option *o = uci_to_option(e);
+		int i;
+
+		for (i = 0; i < n_opts; i++) {
+			if (tb[i])
+				continue;
+
+			if (strcmp(opts[i].name, o->e.name) != 0)
+				continue;
+
+			if (opts[i].type >= 0 && opts[i].type != o->type)
+				continue;
+
+			/* match found */
+			tb[i] = o;
+			break;
+		}
+	}
+}
+
+//-----------------------------------------------------------------------------
+// MurmurHashNeutral2, by Austin Appleby
+
+// Same as MurmurHash2, but endian- and alignment-neutral.
+static uint32_t hash_murmur2(uint32_t h, const void * key, int len)
+{
+	const unsigned char * data = key;
+	const uint32_t m = 0x5bd1e995;
+	const int r = 24;
+
+	while(len >= 4)
+	{
+		unsigned int k;
+
+		k  = data[0];
+		k |= data[1] << 8;
+		k |= data[2] << 16;
+		k |= data[3] << 24;
+
+		k *= m;
+		k ^= k >> r;
+		k *= m;
+
+		h *= m;
+		h ^= k;
+
+		data += 4;
+		len -= 4;
+	}
+
+	switch(len)
+	{
+	case 3: h ^= data[2] << 16;
+	case 2: h ^= data[1] << 8;
+	case 1: h ^= data[0];
+	        h *= m;
+	};
+
+	h ^= h >> 13;
+	h *= m;
+	h ^= h >> 15;
+
+	return h;
+}
+
+static uint32_t uci_hash_list(uint32_t h, struct uci_list *list)
+{
+	struct uci_element *e;
+
+	uci_foreach_element(list, e) {
+		h = hash_murmur2(h, e->name, strlen(e->name) + 1);
+	}
+	return h;
+}
+
+uint32_t uci_hash_options(struct uci_option **tb, int n_opts)
+{
+	uint32_t h = 0xdeadc0de;
+	int i;
+
+	for (i = 0; i < n_opts; i++) {
+		struct uci_option *o = tb[i];
+
+		if (!tb[i])
+			continue;
+
+		h = hash_murmur2(h, o->e.name, strlen(o->e.name) + 1);
+		h = hash_murmur2(h, &o->type, sizeof(o->type));
+
+		switch (tb[i]->type) {
+		case UCI_TYPE_STRING:
+			h = hash_murmur2(h, o->v.string, strlen(o->v.string) + 1);
+			break;
+		case UCI_TYPE_LIST:
+			h = uci_hash_list(h, &o->v.list);
+			break;
+		}
+	}
+
+	return h;
+}
+
+