From 7b405b3e04779fc0a026c9c6ac3e06194948b253 Mon Sep 17 00:00:00 2001
From: Tom Lane <tgl@sss.pgh.pa.us>
Date: Tue, 23 Aug 2016 09:39:54 -0400
Subject: [PATCH] Refactor some network.c code to create
cidr_set_masklen_internal().
Merge several copies of "copy an inet value and adjust the mask length"
code to create a single, conveniently C-callable function. This function
is exported for future use by inet SPGiST support, but it's good cleanup
anyway since we had three slightly-different-for-no-good-reason copies.
(Extracted from a larger patch, to separate new code from refactoring
of old code)
Emre Hasegeli
---
src/backend/utils/adt/network.c | 109 +++++++++-----------------------
src/include/utils/inet.h | 5 +-
2 files changed, 33 insertions(+), 81 deletions(-)
diff --git a/src/backend/utils/adt/network.c b/src/backend/utils/adt/network.c
index 1f8469a2cbc..3f6987af048 100644
--- a/src/backend/utils/adt/network.c
+++ b/src/backend/utils/adt/network.c
@@ -268,11 +268,7 @@ Datum
inet_to_cidr(PG_FUNCTION_ARGS)
{
inet *src = PG_GETARG_INET_PP(0);
- inet *dst;
int bits;
- int byte;
- int nbits;
- int maxbytes;
bits = ip_bits(src);
@@ -280,29 +276,7 @@ inet_to_cidr(PG_FUNCTION_ARGS)
if ((bits < 0) || (bits > ip_maxbits(src)))
elog(ERROR, "invalid inet bit length: %d", bits);
- /* clone the original data */
- dst = (inet *) palloc(VARSIZE_ANY(src));
- memcpy(dst, src, VARSIZE_ANY(src));
-
- /* zero out any bits to the right of the netmask */
- byte = bits / 8;
-
- nbits = bits % 8;
- /* clear the first byte, this might be a partial byte */
- if (nbits != 0)
- {
- ip_addr(dst)[byte] &= ~(0xFF >> nbits);
- byte++;
- }
- /* clear remaining bytes */
- maxbytes = ip_addrsize(dst);
- while (byte < maxbytes)
- {
- ip_addr(dst)[byte] = 0;
- byte++;
- }
-
- PG_RETURN_INET_P(dst);
+ PG_RETURN_INET_P(cidr_set_masklen_internal(src, bits));
}
Datum
@@ -334,10 +308,6 @@ cidr_set_masklen(PG_FUNCTION_ARGS)
{
inet *src = PG_GETARG_INET_PP(0);
int bits = PG_GETARG_INT32(1);
- inet *dst;
- int byte;
- int nbits;
- int maxbytes;
if (bits == -1)
bits = ip_maxbits(src);
@@ -347,31 +317,36 @@ cidr_set_masklen(PG_FUNCTION_ARGS)
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("invalid mask length: %d", bits)));
- /* clone the original data */
- dst = (inet *) palloc(VARSIZE_ANY(src));
- memcpy(dst, src, VARSIZE_ANY(src));
+ PG_RETURN_INET_P(cidr_set_masklen_internal(src, bits));
+}
- ip_bits(dst) = bits;
+/*
+ * Copy src and set mask length to 'bits' (which must be valid for the family)
+ */
+inet *
+cidr_set_masklen_internal(const inet *src, int bits)
+{
+ inet *dst = (inet *) palloc0(sizeof(inet));
- /* zero out any bits to the right of the new netmask */
- byte = bits / 8;
+ ip_family(dst) = ip_family(src);
+ ip_bits(dst) = bits;
- nbits = bits % 8;
- /* clear the first byte, this might be a partial byte */
- if (nbits != 0)
+ if (bits > 0)
{
- ip_addr(dst)[byte] &= ~(0xFF >> nbits);
- byte++;
- }
- /* clear remaining bytes */
- maxbytes = ip_addrsize(dst);
- while (byte < maxbytes)
- {
- ip_addr(dst)[byte] = 0;
- byte++;
+ Assert(bits <= ip_maxbits(dst));
+
+ /* Clone appropriate bytes of the address, leaving the rest 0 */
+ memcpy(ip_addr(dst), ip_addr(src), (bits + 7) / 8);
+
+ /* Clear any unwanted bits in the last partial byte */
+ if (bits % 8)
+ ip_addr(dst)[bits / 8] &= ~(0xFF >> (bits % 8));
}
- PG_RETURN_INET_P(dst);
+ /* Set varlena header correctly */
+ SET_INET_VARSIZE(dst);
+
+ return dst;
}
/*
@@ -719,11 +694,7 @@ network_broadcast(PG_FUNCTION_ARGS)
/* make sure any unused bits are zeroed */
dst = (inet *) palloc0(sizeof(inet));
- if (ip_family(ip) == PGSQL_AF_INET)
- maxbytes = 4;
- else
- maxbytes = 16;
-
+ maxbytes = ip_addrsize(ip);
bits = ip_bits(ip);
a = ip_addr(ip);
b = ip_addr(dst);
@@ -853,11 +824,7 @@ network_hostmask(PG_FUNCTION_ARGS)
/* make sure any unused bits are zeroed */
dst = (inet *) palloc0(sizeof(inet));
- if (ip_family(ip) == PGSQL_AF_INET)
- maxbytes = 4;
- else
- maxbytes = 16;
-
+ maxbytes = ip_addrsize(ip);
bits = ip_maxbits(ip) - ip_bits(ip);
b = ip_addr(dst);
@@ -907,8 +874,7 @@ Datum
inet_merge(PG_FUNCTION_ARGS)
{
inet *a1 = PG_GETARG_INET_PP(0),
- *a2 = PG_GETARG_INET_PP(1),
- *result;
+ *a2 = PG_GETARG_INET_PP(1);
int commonbits;
if (ip_family(a1) != ip_family(a2))
@@ -919,24 +885,7 @@ inet_merge(PG_FUNCTION_ARGS)
commonbits = bitncommon(ip_addr(a1), ip_addr(a2),
Min(ip_bits(a1), ip_bits(a2)));
- /* Make sure any unused bits are zeroed. */
- result = (inet *) palloc0(sizeof(inet));
-
- ip_family(result) = ip_family(a1);
- ip_bits(result) = commonbits;
-
- /* Clone appropriate bytes of the address. */
- if (commonbits > 0)
- memcpy(ip_addr(result), ip_addr(a1), (commonbits + 7) / 8);
-
- /* Clean any unwanted bits in the last partial byte. */
- if (commonbits % 8 != 0)
- ip_addr(result)[commonbits / 8] &= ~(0xFF >> (commonbits % 8));
-
- /* Set varlena header correctly. */
- SET_INET_VARSIZE(result);
-
- PG_RETURN_INET_P(result);
+ PG_RETURN_INET_P(cidr_set_masklen_internal(a1, commonbits));
}
/*
diff --git a/src/include/utils/inet.h b/src/include/utils/inet.h
index 2fe3ca8c3c8..dfa0b9f7113 100644
--- a/src/include/utils/inet.h
+++ b/src/include/utils/inet.h
@@ -28,10 +28,12 @@ typedef struct
} inet_struct;
/*
+ * We use these values for the "family" field.
+ *
* Referencing all of the non-AF_INET types to AF_INET lets us work on
* machines which may not have the appropriate address family (like
* inet6 addresses when AF_INET6 isn't present) but doesn't cause a
- * dump/reload requirement. Existing databases used AF_INET for the family
+ * dump/reload requirement. Pre-7.4 databases used AF_INET for the family
* type on disk.
*/
#define PGSQL_AF_INET (AF_INET + 0)
@@ -117,6 +119,7 @@ typedef struct macaddr
/*
* Support functions in network.c
*/
+extern inet *cidr_set_masklen_internal(const inet *src, int bits);
extern int bitncmp(const unsigned char *l, const unsigned char *r, int n);
extern int bitncommon(const unsigned char *l, const unsigned char *r, int n);
--
GitLab