Add user-callable CRC functions.

We've had code for CRC-32 and CRC-32C for some time (for WAL
records, etc.), but there was no way for users to call it, despite
apparent popular demand.  The new crc32() and crc32c() functions
accept bytea input and return bigint (to avoid returning negative
values).

Bumps catversion.

Author: Aleksander Alekseev
Reviewed-by: Peter Eisentraut, Tom Lane
Discussion: https://postgr.es/m/CAJ7c6TNMTGnqnG%3DyXXUQh9E88JDckmR45H2Q%2B%3DucaCLMOW1QQw%40mail.gmail.com

6 files changed, 81 insertions, 2 deletions

diff --git a/src/backend/utils/hash/pg_crc.c b/src/backend/utils/hash/pg_crc.c
index 3595938dc4f..a85e6171864 100644
--- a/src/backend/utils/hash/pg_crc.c
+++ b/src/backend/utils/hash/pg_crc.c
@@ -17,9 +17,12 @@
  *-------------------------------------------------------------------------
  */
 
-#include "c.h"
+#include "postgres.h"
 
+#include "port/pg_crc32c.h"
+#include "utils/builtins.h"
 #include "utils/pg_crc.h"
+#include "varatt.h"
 
 /*
  * Lookup table for calculating CRC-32 using Sarwate's algorithm.
@@ -95,3 +98,33 @@ const uint32 pg_crc32_table[256] = {
 	0xB3667A2E, 0xC4614AB8, 0x5D681B02, 0x2A6F2B94,
 	0xB40BBE37, 0xC30C8EA1, 0x5A05DF1B, 0x2D02EF8D
 };
+
+/*
+ * SQL-callable functions
+ */
+
+Datum
+crc32_bytea(PG_FUNCTION_ARGS)
+{
+	bytea	   *in = PG_GETARG_BYTEA_PP(0);
+	pg_crc32	crc;
+
+	INIT_TRADITIONAL_CRC32(crc);
+	COMP_TRADITIONAL_CRC32(crc, VARDATA_ANY(in), VARSIZE_ANY_EXHDR(in));
+	FIN_TRADITIONAL_CRC32(crc);
+
+	PG_RETURN_INT64(crc);
+}
+
+Datum
+crc32c_bytea(PG_FUNCTION_ARGS)
+{
+	bytea	   *in = PG_GETARG_BYTEA_PP(0);
+	pg_crc32c	crc;
+
+	INIT_CRC32C(crc);
+	COMP_CRC32C(crc, VARDATA_ANY(in), VARSIZE_ANY_EXHDR(in));
+	FIN_CRC32C(crc);
+
+	PG_RETURN_INT64(crc);
+}
diff --git a/src/include/catalog/catversion.h b/src/include/catalog/catversion.h
index 37c0354ab91..9a0ae278239 100644
--- a/src/include/catalog/catversion.h
+++ b/src/include/catalog/catversion.h
@@ -57,6 +57,6 @@
  */
 
 /*							yyyymmddN */
-#define CATALOG_VERSION_NO	202408121
+#define CATALOG_VERSION_NO	202408122
 
 #endif
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index be37576a34a..4abc6d95262 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -7743,6 +7743,14 @@
   proname => 'system', provolatile => 'v', prorettype => 'tsm_handler',
   proargtypes => 'internal', prosrc => 'tsm_system_handler' },
 
+# CRC variants
+{ oid => '8571', descr => 'CRC-32 value',
+  proname => 'crc32', proleakproof => 't', prorettype => 'int8',
+  proargtypes => 'bytea', prosrc => 'crc32_bytea' },
+{ oid => '8572', descr => 'CRC-32C value',
+  proname => 'crc32c', proleakproof => 't', prorettype => 'int8',
+  proargtypes => 'bytea', prosrc => 'crc32c_bytea' },
+
 # cryptographic
 { oid => '2311', descr => 'MD5 hash',
   proname => 'md5', proleakproof => 't', prorettype => 'text',
diff --git a/src/test/regress/expected/opr_sanity.out b/src/test/regress/expected/opr_sanity.out
index 9d047b21b88..0d734169f11 100644
--- a/src/test/regress/expected/opr_sanity.out
+++ b/src/test/regress/expected/opr_sanity.out
@@ -874,6 +874,8 @@ xid8ne(xid8,xid8)
 xid8cmp(xid8,xid8)
 uuid_extract_timestamp(uuid)
 uuid_extract_version(uuid)
+crc32(bytea)
+crc32c(bytea)
 -- restore normal output mode
 \a\t
 -- List of functions used by libpq's fe-lobj.c
diff --git a/src/test/regress/expected/strings.out b/src/test/regress/expected/strings.out
index 52b69a107fb..b65bb2d5368 100644
--- a/src/test/regress/expected/strings.out
+++ b/src/test/regress/expected/strings.out
@@ -2256,6 +2256,33 @@ SELECT sha512('The quick brown fox jumps over the lazy dog.');
 (1 row)
 
 --
+-- CRC
+--
+SELECT crc32('');
+ crc32 
+-------
+     0
+(1 row)
+
+SELECT crc32('The quick brown fox jumps over the lazy dog.');
+   crc32    
+------------
+ 1368401385
+(1 row)
+
+SELECT crc32c('');
+ crc32c 
+--------
+      0
+(1 row)
+
+SELECT crc32c('The quick brown fox jumps over the lazy dog.');
+  crc32c   
+-----------
+ 419469235
+(1 row)
+
+--
 -- encode/decode
 --
 SELECT encode('\x1234567890abcdef00', 'hex');
diff --git a/src/test/regress/sql/strings.sql b/src/test/regress/sql/strings.sql
index 39596789929..8e0f3a0e75f 100644
--- a/src/test/regress/sql/strings.sql
+++ b/src/test/regress/sql/strings.sql
@@ -720,6 +720,15 @@ SELECT sha512('');
 SELECT sha512('The quick brown fox jumps over the lazy dog.');
 
 --
+-- CRC
+--
+SELECT crc32('');
+SELECT crc32('The quick brown fox jumps over the lazy dog.');
+
+SELECT crc32c('');
+SELECT crc32c('The quick brown fox jumps over the lazy dog.');
+
+--
 -- encode/decode
 --
 SELECT encode('\x1234567890abcdef00', 'hex');