From cd806424137c74fe3993cb119e23b522f44e68f7 Mon Sep 17 00:00:00 2001
From: Peter Eisentraut <peter@eisentraut.org>
Date: Sat, 29 Aug 2015 16:17:13 -0400
Subject: [PATCH] Add hash operator class
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The uri = uri operator was marked as HASHES, but no hash function or
hash operator class was defined.  Hash joins would therefore fail.

Bug report and original patch by Grégoire HUBERT (@chanmix51).

closes #3
---
 Makefile               |  3 ++-
 test/expected/test.out | 11 +++++++++++
 test/sql/test.sql      |  9 +++++++++
 uri--0--1.sql          | 10 ++++++++++
 uri.c                  | 19 +++++++++++++++++++
 uri.control            |  2 +-
 uri.sql                | 11 +++++++++++
 7 files changed, 63 insertions(+), 2 deletions(-)
 create mode 100644 uri--0--1.sql

diff --git a/Makefile b/Makefile
index e1926f9..e8cffe6 100644
--- a/Makefile
+++ b/Makefile
@@ -1,11 +1,12 @@
 PG_CONFIG = pg_config
 PKG_CONFIG = pkg-config
 
-extension_version = 0
+extension_version = 1
 
 EXTENSION = uri
 MODULE_big = uri
 OBJS = uri.o
+DATA = uri--0--1.sql
 DATA_built = uri--$(extension_version).sql
 
 ifeq (no,$(shell $(PKG_CONFIG) liburiparser || echo no))
diff --git a/test/expected/test.out b/test/expected/test.out
index b9fb392..bffb978 100644
--- a/test/expected/test.out
+++ b/test/expected/test.out
@@ -289,3 +289,14 @@ SELECT DISTINCT b FROM test ORDER BY b;
  ssh://username@review.openstack.org:29418/openstack/nova.git
 (17 rows)
 
+CREATE TABLE test2 (x text, y uri);
+INSERT INTO test2 VALUES ('foo', 'http://www.postgresql.org/');
+-- check hashing (issue petere/pguri#3)
+SET enable_nestloop = off;
+SET enable_mergejoin = off;
+SELECT * FROM test JOIN test2 ON b = y AND a = 1;
+ a |             b              |  x  |             y              
+---+----------------------------+-----+----------------------------
+ 1 | http://www.postgresql.org/ | foo | http://www.postgresql.org/
+(1 row)
+
diff --git a/test/sql/test.sql b/test/sql/test.sql
index abe6e23..7c3ceb8 100644
--- a/test/sql/test.sql
+++ b/test/sql/test.sql
@@ -48,3 +48,12 @@ SELECT b AS uri,
 \x off
 
 SELECT DISTINCT b FROM test ORDER BY b;
+
+
+CREATE TABLE test2 (x text, y uri);
+INSERT INTO test2 VALUES ('foo', 'http://www.postgresql.org/');
+
+-- check hashing (issue petere/pguri#3)
+SET enable_nestloop = off;
+SET enable_mergejoin = off;
+SELECT * FROM test JOIN test2 ON b = y AND a = 1;
diff --git a/uri--0--1.sql b/uri--0--1.sql
new file mode 100644
index 0000000..c862c9c
--- /dev/null
+++ b/uri--0--1.sql
@@ -0,0 +1,10 @@
+CREATE FUNCTION uri_hash(uri) RETURNS integer
+    IMMUTABLE
+    STRICT
+    LANGUAGE C
+    AS '$libdir/uri';
+
+CREATE OPERATOR CLASS uri_ops_hash
+    DEFAULT FOR TYPE uri USING hash AS
+        OPERATOR        1       =,
+        FUNCTION        1       uri_hash(uri);
diff --git a/uri.c b/uri.c
index 3fad2e1..85ca239 100644
--- a/uri.c
+++ b/uri.c
@@ -1,4 +1,5 @@
 #include <postgres.h>
+#include <access/hash.h>
 #include <catalog/pg_type.h>
 #include <fmgr.h>
 #include <lib/stringinfo.h>
@@ -16,9 +17,11 @@ typedef struct varlena uritype;
 
 
 #define DatumGetUriP(X)		((uritype *) PG_DETOAST_DATUM(X))
+#define DatumGetUriPP(X)	((uritype *) PG_DETOAST_DATUM_PACKED(X))
 #define UriPGetDatum(X)		PointerGetDatum(X)
 
 #define PG_GETARG_URI_P(n)	DatumGetUriP(PG_GETARG_DATUM(n))
+#define PG_GETARG_URI_PP(n)	DatumGetUriPP(PG_GETARG_DATUM(n))
 #define PG_RETURN_URI_P(x)	PG_RETURN_POINTER(x)
 
 
@@ -436,3 +439,19 @@ uri_cmp(PG_FUNCTION_ARGS)
 
 	PG_RETURN_INT32(_uri_cmp(arg1, arg2));
 }
+
+PG_FUNCTION_INFO_V1(uri_hash);
+Datum
+uri_hash(PG_FUNCTION_ARGS)
+{
+	uritype	   *key = PG_GETARG_URI_PP(0);
+	Datum		result;
+
+	result = hash_any((unsigned char *) VARDATA_ANY(key),
+					  VARSIZE_ANY_EXHDR(key));
+
+	/* Avoid leaking memory for toasted inputs */
+	PG_FREE_IF_COPY(key, 0);
+
+	return result;
+}
diff --git a/uri.control b/uri.control
index e07dc2a..6c78246 100644
--- a/uri.control
+++ b/uri.control
@@ -1,4 +1,4 @@
 comment = 'uri type'
-default_version = 0
+default_version = 1
 module_pathname = '$libdir/uri'
 relocatable = true
diff --git a/uri.sql b/uri.sql
index edf5261..7f68cb1 100644
--- a/uri.sql
+++ b/uri.sql
@@ -130,6 +130,12 @@ CREATE FUNCTION uri_cmp(uri, uri) RETURNS integer
     LANGUAGE C
     AS '$libdir/uri';
 
+CREATE FUNCTION uri_hash(uri) RETURNS integer
+    IMMUTABLE
+    STRICT
+    LANGUAGE C
+    AS '$libdir/uri';
+
 CREATE OPERATOR < (
     LEFTARG = uri,
     RIGHTARG = uri,
@@ -200,3 +206,8 @@ CREATE OPERATOR CLASS uri_ops
         OPERATOR        4       >= ,
         OPERATOR        5       > ,
         FUNCTION        1       uri_cmp(uri, uri);
+
+CREATE OPERATOR CLASS uri_ops_hash
+    DEFAULT FOR TYPE uri USING hash AS
+        OPERATOR        1       =,
+        FUNCTION        1       uri_hash(uri);