Squash set_offsets() and dns_name_offsets() into single function

The third argument to set_offsets() was only used in
dns_name_fromregion() and not really needed.  We can remove the third
argument and then manually check whether the last label is root label.

diff --git a/lib/dns/name.c b/lib/dns/name.c
index 64ba2878046306cfa485985f417ef1e524de1cc0..12201c05d8d988f73e6b7975517d832a3305b4cb 100644 (file)
--- a/lib/dns/name.c
+++ b/lib/dns/name.c
@@ -65,10 +65,6 @@ const dns_name_t *dns_wildcardname = &wild;
  */
 static thread_local dns_name_totextfilter_t *totext_filter_proc = NULL;
 
-static uint8_t
-set_offsets(const dns_name_t *name, dns_offsets_t offsets,
-           dns_name_t *set_name);
-
 bool
 dns_name_isvalid(const dns_name_t *name) {
        unsigned char *ndata;
@@ -647,8 +643,7 @@ dns_name_clone(const dns_name_t *source, dns_name_t *target) {
 
 void
 dns_name_fromregion(dns_name_t *name, const isc_region_t *r) {
-       dns_offsets_t offsets;
-       unsigned int len;
+       size_t length;
        isc_region_t r2 = { .base = NULL, .length = 0 };
 
        /*
@@ -663,21 +658,38 @@ dns_name_fromregion(dns_name_t *name, const isc_region_t *r) {
        if (name->buffer != NULL) {
                isc_buffer_clear(name->buffer);
                isc_buffer_availableregion(name->buffer, &r2);
-               len = (r->length < r2.length) ? r->length : r2.length;
-               if (len > DNS_NAME_MAXWIRE) {
-                       len = DNS_NAME_MAXWIRE;
+               length = (r->length < r2.length) ? r->length : r2.length;
+               if (length > DNS_NAME_MAXWIRE) {
+                       length = DNS_NAME_MAXWIRE;
                }
-               name->length = len;
        } else {
-               name->length = (r->length <= DNS_NAME_MAXWIRE)
-                                      ? r->length
-                                      : DNS_NAME_MAXWIRE;
+               length = (r->length <= DNS_NAME_MAXWIRE) ? r->length
+                                                        : DNS_NAME_MAXWIRE;
        }
 
-       if (r->length > 0) {
-               set_offsets(name, offsets, name);
-       } else {
-               name->attributes.absolute = false;
+       name->attributes.absolute = false;
+
+       if (length > 0) {
+               size_t offset = 0;
+               uint8_t nlabels = 0;
+               while (offset != length) {
+                       uint8_t count;
+
+                       INSIST(nlabels < DNS_NAME_MAXLABELS);
+                       nlabels++;
+
+                       count = name->ndata[offset];
+                       INSIST(count <= DNS_NAME_LABELLEN);
+
+                       offset += count + 1;
+                       INSIST(offset <= length);
+
+                       if (count == 0) {
+                               name->attributes.absolute = true;
+                               break;
+                       }
+               }
+               name->length = offset;
        }
 
        if (name->buffer != NULL) {
@@ -1261,45 +1273,6 @@ dns_name_downcase(const dns_name_t *source, dns_name_t *name) {
        return ISC_R_SUCCESS;
 }
 
-static uint8_t
-set_offsets(const dns_name_t *name, dns_offsets_t offsets,
-           dns_name_t *set_name) {
-       unsigned int offset, count, length, nlabels;
-       unsigned char *ndata;
-       bool absolute;
-
-       ndata = name->ndata;
-       length = name->length;
-       offset = 0;
-       nlabels = 0;
-       absolute = false;
-       while (offset != length) {
-               INSIST(nlabels < DNS_NAME_MAXLABELS);
-               if (offsets != NULL) {
-                       offsets[nlabels] = offset;
-               }
-               nlabels++;
-               count = *ndata;
-               INSIST(count <= DNS_NAME_LABELLEN);
-               offset += count + 1;
-               ndata += count + 1;
-               INSIST(offset <= length);
-               if (count == 0) {
-                       absolute = true;
-                       break;
-               }
-       }
-       if (set_name != NULL) {
-               INSIST(set_name == name);
-
-               set_name->length = offset;
-               set_name->attributes.absolute = absolute;
-       }
-       INSIST(offset == name->length);
-
-       return nlabels;
-}
-
 isc_result_t
 dns_name_fromwire(dns_name_t *const name, isc_buffer_t *const source,
                  const dns_decompress_t dctx, isc_buffer_t *target) {
@@ -2131,5 +2104,30 @@ dns_name_israd(const dns_name_t *name, const dns_name_t *rad) {
 uint8_t
 dns_name_offsets(const dns_name_t *name, dns_offsets_t offsets) {
        REQUIRE(DNS_NAME_VALID(name));
-       return set_offsets(name, offsets, NULL);
+       unsigned int offset, count, length, nlabels;
+       unsigned char *ndata;
+
+       ndata = name->ndata;
+       length = name->length;
+       offset = 0;
+       nlabels = 0;
+       while (offset != length) {
+               INSIST(nlabels < DNS_NAME_MAXLABELS);
+               if (offsets != NULL) {
+                       offsets[nlabels] = offset;
+               }
+               nlabels++;
+               count = *ndata;
+               INSIST(count <= DNS_NAME_LABELLEN);
+               offset += count + 1;
+               ndata += count + 1;
+               INSIST(offset <= length);
+               if (count == 0) {
+                       /* Final root label */
+                       break;
+               }
+       }
+       INSIST(offset == name->length);
+
+       return nlabels;
 }