Remove some remnants of bitstring labels

* rbt node chains were sized to allow for bitstring labels, so they
  had 256 levels; but in the absence of bistrings, 128 is enough.

* dns_byaddr_createptrname() had a redundant options argument,
  and a very outdated doc comment.

* A number of comments referred to bitstring labels in a way that is
  no longer helpful. (A few informative comments remain.)

diff --git a/CHANGES b/CHANGES
index 6f5472d783b5be434b5eddffc1efba50a12f79cb..b8ec7679956e6ab9ed911d1a91407d8c57ee9971 100644 (file)
--- a/CHANGES
+++ b/CHANGES
@@ -1,3 +1,5 @@
+6086.  [cleanup]       Remove some remnants of bitstring labels. [GL !7196]
+
 6085.  [func]          Add isc_time_monotonic() to simplify time measurements.
                        [GL !7468]
 

diff --git a/bin/delv/delv.c b/bin/delv/delv.c
index 132d5dda346db524099fd2fc8d7a1735bc50e9c4..13c85b240a46580cd0364a5a83842a0bf96a9c90 100644 (file)
--- a/bin/delv/delv.c
+++ b/bin/delv/delv.c
@@ -1688,10 +1688,9 @@ get_reverse(char *reverse, size_t len, char *value, bool strict) {
                /* This is a valid IPv6 address. */
                dns_fixedname_t fname;
                dns_name_t *name;
-               unsigned int options = 0;
 
                name = dns_fixedname_initname(&fname);
-               result = dns_byaddr_createptrname(&addr, options, name);
+               result = dns_byaddr_createptrname(&addr, name);
                if (result != ISC_R_SUCCESS) {
                        return (result);
                }

diff --git a/bin/dig/dighost.c b/bin/dig/dighost.c
index 1a1c14feca146234e1d405bd0991e21910d0610b..6e4aefc51e602daf906c32c279ce7c1d7e7c1c80 100644 (file)
--- a/bin/dig/dighost.c
+++ b/bin/dig/dighost.c
@@ -328,10 +328,9 @@ get_reverse(char *reverse, size_t len, char *value, bool strict) {
                /* This is a valid IPv6 address. */
                dns_fixedname_t fname;
                dns_name_t *name;
-               unsigned int options = 0;
 
                name = dns_fixedname_initname(&fname);
-               result = dns_byaddr_createptrname(&addr, options, name);
+               result = dns_byaddr_createptrname(&addr, name);
                if (result != ISC_R_SUCCESS) {
                        return (result);
                }

diff --git a/bin/tests/system/dyndb/driver/syncptr.c b/bin/tests/system/dyndb/driver/syncptr.c
index 5124df32b4d235c7978effc05fb154605e04c331..edf6f8271a8edf41aacb30955931c945319af373 100644 (file)
--- a/bin/tests/system/dyndb/driver/syncptr.c
+++ b/bin/tests/system/dyndb/driver/syncptr.c
@@ -167,7 +167,7 @@ syncptr_find_zone(sample_instance_t *inst, dns_rdata_t *rdata, dns_name_t *name,
         * @example
         * 192.168.0.1 -> 1.0.168.192.in-addr.arpa
         */
-       result = dns_byaddr_createptrname(&isc_ip, 0, name);
+       result = dns_byaddr_createptrname(&isc_ip, name);
        if (result != ISC_R_SUCCESS) {
                log_write(ISC_LOG_ERROR,
                          "syncptr_find_zone: dns_byaddr_createptrname -> %s\n",

diff --git a/bin/tools/mdig.c b/bin/tools/mdig.c
index d0bed78d07d9273b2f31c984dcc45aad98a63952..b964dabdec89b07b616b2716c319551f7b8d3042 100644 (file)
--- a/bin/tools/mdig.c
+++ b/bin/tools/mdig.c
@@ -1091,11 +1091,10 @@ get_reverse(char *reverse, size_t len, const char *value) {
                /* This is a valid IPv6 address. */
                dns_fixedname_t fname;
                dns_name_t *name;
-               unsigned int options = 0;
 
                name = dns_fixedname_initname(&fname);
-               result = dns_byaddr_createptrname(&addr, options, name);
-               CHECK("dns_byaddr_createptrname2", result);
+               result = dns_byaddr_createptrname(&addr, name);
+               CHECK("dns_byaddr_createptrname", result);
                dns_name_format(name, reverse, (unsigned int)len);
                return;
        } else {

diff --git a/lib/dns/byaddr.c b/lib/dns/byaddr.c
index 1b17b249346c2c9da0c5eddbcf4a8be4deb16828..6297230cebd2a01c521394c31d28fd27abf1b2db 100644 (file)
--- a/lib/dns/byaddr.c
+++ b/lib/dns/byaddr.c
@@ -40,8 +40,7 @@ static char hex_digits[] = { '0', '1', '2', '3', '4', '5', '6', '7',
                             '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' };
 
 isc_result_t
-dns_byaddr_createptrname(const isc_netaddr_t *address, unsigned int options,
-                        dns_name_t *name) {
+dns_byaddr_createptrname(const isc_netaddr_t *address, dns_name_t *name) {
        char textname[128];
        const unsigned char *bytes;
        int i;
@@ -50,7 +49,6 @@ dns_byaddr_createptrname(const isc_netaddr_t *address, unsigned int options,
        unsigned int len;
 
        REQUIRE(address != NULL);
-       UNUSED(options);
 
        /*
         * We create the text representation and then convert to a

diff --git a/lib/dns/include/dns/byaddr.h b/lib/dns/include/dns/byaddr.h
index 20e0f53dd967604ef9161cfb0f7663f92fd3b9f3..4c18ddad282c0931f8d0448decda0f0c4b464642 100644 (file)
--- a/lib/dns/include/dns/byaddr.h
+++ b/lib/dns/include/dns/byaddr.h
@@ -48,14 +48,9 @@
 ISC_LANG_BEGINDECLS
 
 isc_result_t
-dns_byaddr_createptrname(const isc_netaddr_t *address, unsigned int options,
-                        dns_name_t *name);
+dns_byaddr_createptrname(const isc_netaddr_t *address, dns_name_t *name);
 /*%<
- * Creates a name that would be used in a PTR query for this address.  The
- * nibble flag indicates that the 'nibble' format is to be used if an IPv6
- * address is provided, instead of the 'bitstring' format.  Since we dropped
- * the support of the bitstring labels, it is expected that the flag is always
- * set.  'options' are the same as for dns_byaddr_create().
+ * Creates a name that would be used in a PTR query for this address.
  *
  * Requires:
  *

diff --git a/lib/dns/include/dns/rbt.h b/lib/dns/include/dns/rbt.h
index 4651edcf4dc0174f7a0a742c63cd2f8a82ad666b..bf5b23eb67c2d0188d5c480e125d804b4af0b52d 100644 (file)
--- a/lib/dns/include/dns/rbt.h
+++ b/lib/dns/include/dns/rbt.h
@@ -211,15 +211,13 @@ typedef void (*dns_rbtdeleter_t)(void *, void *);
  */
 
 /*%
- * The number of level blocks to allocate at a time.  Currently the maximum
- * number of levels is allocated directly in the structure, but future
- * revisions of this code might have a static initial block with dynamic
- * growth.  Allocating space for 256 levels when the tree is almost never that
- * deep is wasteful, but it's not clear that it matters, since the waste is
- * only 2MB for 1000 concurrently active chains on a system with 64-bit
- * pointers.
+ * The number of level blocks to allocate at a time, same as the maximum
+ * number of labels. Allocating space for 128 levels when the tree is
+ * almost never that deep is wasteful, but it's not clear that it matters,
+ * since the waste is only 1MB for 1000 concurrently active chains on a
+ * system with 64-bit pointers.
  */
-#define DNS_RBT_LEVELBLOCK 254
+#define DNS_RBT_LEVELBLOCK 127
 
 typedef struct dns_rbtnodechain {
        unsigned int magic;
@@ -231,12 +229,9 @@ typedef struct dns_rbtnodechain {
         */
        dns_rbtnode_t *end;
        /*%
-        * The maximum number of labels in a name is 128; bitstrings mean
-        * a conceptually very large number (which I have not bothered to
-        * compute) of logical levels because splitting can potentially occur
-        * at each bit.  However, DNSSEC restricts the number of "logical"
-        * labels in a name to 255, meaning only 254 pointers are needed
-        * in the worst case.
+        * Currently the maximum number of levels is allocated directly in
+        * the structure, but future revisions of this code might have a
+        * static initial block with dynamic growth.
         */
        dns_rbtnode_t *levels[DNS_RBT_LEVELBLOCK];
        /*%

diff --git a/lib/dns/rbt.c b/lib/dns/rbt.c
index 2f51e9564d34df6b92acd35c4f6a19e681cab409..eb3460c8eeea8340585f7d02f3db4c8bf92f6825 100644 (file)
--- a/lib/dns/rbt.c
+++ b/lib/dns/rbt.c
@@ -793,9 +793,8 @@ dns_rbt_findnode(dns_rbt_t *rbt, const dns_name_t *name, dns_name_t *foundname,
        /*
         * search_name is the name segment being sought in each tree level.
         * By using a fixedname, the search_name will definitely have offsets
-        * for use by any splitting.
-        * By using dns_name_clone, no name data should be copied thanks to
-        * the lack of bitstring labels.
+        * for use by any splitting. By using dns_name_clone, no name data
+        * should be copied.
         */
        search_name = dns_fixedname_initname(&fixedsearchname);
        INSIST(search_name != NULL);
@@ -949,8 +948,7 @@ dns_rbt_findnode(dns_rbt_t *rbt, const dns_name_t *name, dns_name_t *foundname,
 
                        /*
                         * All of the labels have been tried against the hash
-                        * table.  Since we dropped the support of bitstring
-                        * labels, the name isn't in the table.
+                        * table.
                         */
                        current = NULL;
                        continue;

diff --git a/lib/dns/result.c b/lib/dns/result.c
index 65e2a4a4546f78bc7aa16649ab8e55fd662d54d8..86b7a8f6fbfa4d550b8c3e1b54f84fe200522a6b 100644 (file)
--- a/lib/dns/result.c
+++ b/lib/dns/result.c
@@ -44,14 +44,12 @@ dns_result_torcode(isc_result_t result) {
        case ISC_R_RANGE:
        case ISC_R_UNEXPECTEDEND:
        case DNS_R_BADAAAA:
-       /* case DNS_R_BADBITSTRING: deprecated */
        case DNS_R_BADCKSUM:
        case DNS_R_BADCLASS:
        case DNS_R_BADLABELTYPE:
        case DNS_R_BADPOINTER:
        case DNS_R_BADTTL:
        case DNS_R_BADZONE:
-       /* case DNS_R_BITSTRINGTOOLONG: deprecated */
        case DNS_R_EXTRADATA:
        case DNS_R_LABELTOOLONG:
        case DNS_R_NOREDATA: