venum-poc.patch

Index: enum.c
===================================================================
RCS file: /cvsroot/pgsql/src/backend/utils/adt/enum.c,v
retrieving revision 1.11
diff -c -r1.11 enum.c
*** enum.c	26 Feb 2010 02:01:08 -0000	1.11
--- enum.c	22 Jun 2010 02:16:48 -0000
***************
*** 14,19 ****
--- 14,20 ----
  #include "postgres.h"
  
  #include "catalog/pg_enum.h"
+ #include "catalog/pg_type.h"
  #include "fmgr.h"
  #include "utils/array.h"
  #include "utils/builtins.h"
***************
*** 22,27 ****
--- 23,52 ----
  #include "libpq/pqformat.h"
  #include "miscadmin.h"
  
+ typedef struct 
+ {
+ 	Oid      enum_oid;
+ 	uint32   sort_order;
+ } enum_sort;
+ 
+ typedef struct 
+ {
+ 	bool      oids_are_sorted;
+ 	int       sort_list_length;
+ 	enum_sort sort_order_list[1024];
+ } enum_sort_cache;
+ 	
+ 
+ static int 
+ enum_sort_cmp(void * es1, void * es2)
+ {
+ 	enum_sort *p1, *p2;
+ 	p1 = (enum_sort *)es1;
+ 	p2 = (enum_sort *)es2;
+ 	return p1->enum_oid - p2->enum_oid;
+ }
+ 
+ 
  
  static ArrayType *enum_range_internal(Oid enumtypoid, Oid lower, Oid upper);
  static int	enum_elem_cmp(const void *left, const void *right);
***************
*** 155,167 ****
  
  /* Comparison functions and related */
  
  Datum
  enum_lt(PG_FUNCTION_ARGS)
  {
  	Oid			a = PG_GETARG_OID(0);
  	Oid			b = PG_GETARG_OID(1);
  
! 	PG_RETURN_BOOL(a < b);
  }
  
  Datum
--- 180,283 ----
  
  /* Comparison functions and related */
  
+ static inline int 
+ enum_ccmp(Oid arg1, Oid arg2, FunctionCallInfo fcinfo)
+ {
+ 
+ 	enum_sort_cache * mycache;
+ 	enum_sort *es1, *es2;
+ 	int sort1, sort2;
+ 	bool added = false;
+ 	HeapTuple	tup;
+ 	Form_pg_enum en;
+ 	Oid typeoid;
+ 	Form_pg_type typ;
+ 
+ 	if (arg1 == arg2)
+ 		return 0;
+ 
+ 	mycache = (enum_sort_cache *) fcinfo->flinfo->fn_extra;
+ 	if (mycache == NULL )
+ 	{
+         fcinfo->flinfo->fn_extra = MemoryContextAlloc(fcinfo->flinfo->fn_mcxt,
+                                                       sizeof(enum_sort_cache));
+         mycache = (enum_sort_cache *) fcinfo->flinfo->fn_extra;
+ 		mycache->sort_list_length = 1;
+ 		tup = SearchSysCache1(ENUMOID, ObjectIdGetDatum(arg1));
+ 		en = (Form_pg_enum) GETSTRUCT(tup);
+ 		mycache->sort_order_list[0].enum_oid = arg1;
+ 		mycache->sort_order_list[0].sort_order = arg1;
+ 		typeoid = en->enumtypid;
+ 		ReleaseSysCache(tup);
+ 		tup = SearchSysCache1(TYPEOID, ObjectIdGetDatum(typeoid));
+ 		typ = (Form_pg_type)  GETSTRUCT(tup);
+ 		if (typ->typtype != 'e')
+ 			elog(ERROR,"wrong type for oid %u",typeoid);
+ 		/* XXX TODO fill in oids_are_sorted property from type tuple here */
+ 		mycache->oids_are_sorted = false;
+ 		ReleaseSysCache(tup);
+ 	}
+ 
+ 	if (mycache->oids_are_sorted)
+ 		return arg1 - arg2;
+ 
+ 	es1 = bsearch(&arg1,mycache->sort_order_list,mycache->sort_list_length,
+ 				  sizeof(enum_sort),enum_sort_cmp);
+ 	es2 = bsearch(&arg2,mycache->sort_order_list,mycache->sort_list_length,
+ 				  sizeof(enum_sort),enum_sort_cmp);
+ 
+ 	if (es1 == NULL)
+ 	{
+ 		
+ 		tup = SearchSysCache1(ENUMOID, ObjectIdGetDatum(arg1));
+ 		en = (Form_pg_enum) GETSTRUCT(tup);
+ 		mycache->sort_order_list[mycache->sort_list_length].enum_oid = arg1;
+ 		sort1 = arg1; /* XXX should be en->enumsort */
+ 		mycache->sort_order_list[mycache->sort_list_length].sort_order = 
+ 			sort1; 
+ 		ReleaseSysCache(tup);
+ 		mycache->sort_list_length ++;
+ 		added = true;
+ 	}
+ 	else
+ 	{
+ 		/* already in cache */
+ 		sort1 = es1->sort_order;
+ 	}
+ 
+ 	if (es2 == NULL)
+ 	{
+ 		
+ 		tup = SearchSysCache1(ENUMOID, ObjectIdGetDatum(arg2));
+ 		en = (Form_pg_enum) GETSTRUCT(tup);
+ 		sort2 = arg2; /* XXX should be en->enumsort */
+ 		mycache->sort_order_list[mycache->sort_list_length].enum_oid = arg2;
+ 		mycache->sort_order_list[mycache->sort_list_length].sort_order = 
+ 			sort2;
+ 		ReleaseSysCache(tup);
+ 		mycache->sort_list_length ++;
+ 		added = true;
+ 	}
+ 	else
+ 	{
+ 		/* already in cache */
+ 		sort2 = es2->sort_order;
+ 	}
+ 
+ 	if (added)
+ 		qsort(mycache->sort_order_list,mycache->sort_list_length,
+ 			  sizeof(enum_sort),enum_sort_cmp);
+ 
+ 	return sort1 - sort2;
+ }
+ 
  Datum
  enum_lt(PG_FUNCTION_ARGS)
  {
  	Oid			a = PG_GETARG_OID(0);
  	Oid			b = PG_GETARG_OID(1);
  
! 	PG_RETURN_BOOL(enum_ccmp(a,b,fcinfo) < 0);
  }
  
  Datum
***************
*** 170,176 ****
  	Oid			a = PG_GETARG_OID(0);
  	Oid			b = PG_GETARG_OID(1);
  
! 	PG_RETURN_BOOL(a <= b);
  }
  
  Datum
--- 286,292 ----
  	Oid			a = PG_GETARG_OID(0);
  	Oid			b = PG_GETARG_OID(1);
  
! 	PG_RETURN_BOOL(enum_ccmp(a,b,fcinfo) <= 0);
  }
  
  Datum
***************
*** 197,203 ****
  	Oid			a = PG_GETARG_OID(0);
  	Oid			b = PG_GETARG_OID(1);
  
! 	PG_RETURN_BOOL(a >= b);
  }
  
  Datum
--- 313,319 ----
  	Oid			a = PG_GETARG_OID(0);
  	Oid			b = PG_GETARG_OID(1);
  
! 	PG_RETURN_BOOL(enum_ccmp(a,b,fcinfo) >= 0);
  }
  
  Datum
***************
*** 206,212 ****
  	Oid			a = PG_GETARG_OID(0);
  	Oid			b = PG_GETARG_OID(1);
  
! 	PG_RETURN_BOOL(a > b);
  }
  
  Datum
--- 322,328 ----
  	Oid			a = PG_GETARG_OID(0);
  	Oid			b = PG_GETARG_OID(1);
  
! 	PG_RETURN_BOOL(enum_ccmp(a,b,fcinfo) > 0);
  }
  
  Datum
***************
*** 233,242 ****
  	Oid			a = PG_GETARG_OID(0);
  	Oid			b = PG_GETARG_OID(1);
  
! 	if (a > b)
! 		PG_RETURN_INT32(1);
! 	else if (a == b)
  		PG_RETURN_INT32(0);
  	else
  		PG_RETURN_INT32(-1);
  }
--- 349,358 ----
  	Oid			a = PG_GETARG_OID(0);
  	Oid			b = PG_GETARG_OID(1);
  
! 	if (a == b)
  		PG_RETURN_INT32(0);
+ 	else if (enum_ccmp(a,b,fcinfo) > 0)
+ 		PG_RETURN_INT32(1);
  	else
  		PG_RETURN_INT32(-1);
  }