From 13cf8679db6fcdf026412c4aea563a88f2758cdb Mon Sep 17 00:00:00 2001
From: Daniele Varrazzo <daniele.varrazzo@gmail.com>
Date: Sun, 9 Dec 2012 12:02:49 +0000
Subject: [PATCH] Added support for COLLATE to index keys

---
 bin/expected/repack.out |  7 +++++++
 bin/sql/repack.sql      |  2 ++
 lib/repack.c            | 16 +++++++++++-----
 3 files changed, 20 insertions(+), 5 deletions(-)

diff --git a/bin/expected/repack.out b/bin/expected/repack.out
index 9dfb4eb..f1bc1ad 100644
--- a/bin/expected/repack.out
+++ b/bin/expected/repack.out
@@ -322,6 +322,7 @@ CREATE UNIQUE INDEX issue3_idx1 ON issue3 (col1, col2 DESC);
 CREATE UNIQUE INDEX issue3_idx2 ON issue3 (col1 DESC, col2 text_pattern_ops);
 CREATE UNIQUE INDEX issue3_idx3 ON issue3 (col1 DESC, col2 DESC);
 CREATE UNIQUE INDEX issue3_idx4 ON issue3 (col1 NULLS FIRST, col2 text_pattern_ops DESC NULLS LAST);
+CREATE UNIQUE INDEX issue3_idx5 ON issue3 (col1 DESC NULLS FIRST, col2 COLLATE "POSIX" DESC);
 SELECT repack.get_order_by('issue3_idx1'::regclass::oid, 'issue3'::regclass::oid);
   get_order_by   
 -----------------
@@ -346,3 +347,9 @@ SELECT repack.get_order_by('issue3_idx4'::regclass::oid, 'issue3'::regclass::oid
  col1 NULLS FIRST, col2 DESC USING ~<~ NULLS LAST
 (1 row)
 
+SELECT repack.get_order_by('issue3_idx5'::regclass::oid, 'issue3'::regclass::oid);
+             get_order_by             
+--------------------------------------
+ col1 DESC, col2 COLLATE "POSIX" DESC
+(1 row)
+
diff --git a/bin/sql/repack.sql b/bin/sql/repack.sql
index 2268c8b..fc05411 100644
--- a/bin/sql/repack.sql
+++ b/bin/sql/repack.sql
@@ -196,8 +196,10 @@ CREATE UNIQUE INDEX issue3_idx1 ON issue3 (col1, col2 DESC);
 CREATE UNIQUE INDEX issue3_idx2 ON issue3 (col1 DESC, col2 text_pattern_ops);
 CREATE UNIQUE INDEX issue3_idx3 ON issue3 (col1 DESC, col2 DESC);
 CREATE UNIQUE INDEX issue3_idx4 ON issue3 (col1 NULLS FIRST, col2 text_pattern_ops DESC NULLS LAST);
+CREATE UNIQUE INDEX issue3_idx5 ON issue3 (col1 DESC NULLS FIRST, col2 COLLATE "POSIX" DESC);
 
 SELECT repack.get_order_by('issue3_idx1'::regclass::oid, 'issue3'::regclass::oid);
 SELECT repack.get_order_by('issue3_idx2'::regclass::oid, 'issue3'::regclass::oid);
 SELECT repack.get_order_by('issue3_idx3'::regclass::oid, 'issue3'::regclass::oid);
 SELECT repack.get_order_by('issue3_idx4'::regclass::oid, 'issue3'::regclass::oid);
+SELECT repack.get_order_by('issue3_idx5'::regclass::oid, 'issue3'::regclass::oid);
diff --git a/lib/repack.c b/lib/repack.c
index bd4e9e0..1bfec43 100644
--- a/lib/repack.c
+++ b/lib/repack.c
@@ -473,14 +473,13 @@ parse_indexdef(IndexDef *stmt, Oid index, Oid table)
 }
 
 /*
- * Parse the trailing ... [ DESC ] [ NULLS { FIRST | LAST } ] from an index
+ * Parse the trailing ... [ COLLATE X ] [ DESC ] [ NULLS { FIRST | LAST } ] from an index
  * definition column.
  * Returned values point to token. \0's are inserted to separate parsed parts.
  */
 static void
-parse_desc_nulls(char *token, char **desc, char **nulls)
+parse_indexdef_col(char *token, char **desc, char **nulls, char **collate)
 {
-#if PG_VERSION_NUM >= 80300
 	char *pos;
 
 	/* easier to walk backwards than to parse quotes and escapes... */
@@ -499,7 +498,11 @@ parse_desc_nulls(char *token, char **desc, char **nulls)
 		*desc = pos + 1;
 		*pos = '\0';
 	}
-#endif
+	if (NULL != (pos = strstr(token, " COLLATE ")))
+	{
+		*collate = pos + 1;
+		*pos = '\0';
+	}
 }
 
 /**
@@ -543,14 +546,17 @@ repack_get_order_by(PG_FUNCTION_ARGS)
 		char *opcname;
 		char *coldesc = NULL;
 		char *colnulls = NULL;
+		char *colcollate = NULL;
 
 		token = next;
 		while (isspace((unsigned char) *token))
 			token++;
 		next = skip_until(index, next, ',');
-		parse_desc_nulls(token, &coldesc, &colnulls);
+		parse_indexdef_col(token, &coldesc, &colnulls, &colcollate);
 		opcname = skip_until(index, token, ' ');
 		appendStringInfoString(&str, token);
+		if (colcollate)
+			appendStringInfo(&str, " %s", colcollate);
 		if (coldesc)
 			appendStringInfo(&str, " %s", coldesc);
 		if (opcname)