Re-work prepared geom cache to use memcmp instead of keys, step 1.

git-svn-id: http://svn.osgeo.org/postgis/trunk@3074 b70326c6-7e19-0410-871a-916f4a2858ee

diff --git a/lwgeom/lwgeom_geos_c.c b/lwgeom/lwgeom_geos_c.c
index 62ab6d0189c4d41b65cf631c17db800b625085cc..db29e626cd25e450521ad31a83e3264b9645f63a 100644 (file)
--- a/lwgeom/lwgeom_geos_c.c
+++ b/lwgeom/lwgeom_geos_c.c
@@ -3564,6 +3564,10 @@ typedef struct
 {
        int32                         key1;
        int32                         key2;
+       uchar*                         serialized1;
+       uchar*                         serialized2;
+       size_t                        serialized1_size;
+       size_t                        serialized2_size;
        int32                         argnum;
        const GEOSPreparedGeometry*   prepared_geom;
        const GEOSGeometry*           geom;
@@ -3591,11 +3595,11 @@ typedef struct
 } PrepGeomHashEntry;
 
 /* Utility function to pull or prepare the current cache */
-PrepGeomCache *GetPrepGeomCache(FunctionCallInfoData *fcinfo, PG_LWGEOM *serialized_geom1, PG_LWGEOM *serialized_geom2, int32 key1, int32 key2);
+PrepGeomCache *GetPrepGeomCache(FunctionCallInfoData *fcinfo, uchar *serialized_geom1, uchar *serialized_geom2);
 
 /* Memory context hash table function prototypes */
 uint32 mcxt_ptr_hasha(const void *key, Size keysize);
-static HTAB* CreatePrepGeomHash(void);
+static void CreatePrepGeomHash(void);
 static void AddPrepGeomHashEntry(PrepGeomHashEntry pghe);
 static PrepGeomHashEntry *GetPrepGeomHashEntry(MemoryContext mcxt);
 static void DeletePrepGeomHashEntry(MemoryContext mcxt);
@@ -3714,7 +3718,7 @@ mcxt_ptr_hasha(const void *key, Size keysize)
        return hashval;
 }
 
-static HTAB*
+static void
 CreatePrepGeomHash(void)
 {
        HASHCTL ctl;
@@ -3723,7 +3727,7 @@ CreatePrepGeomHash(void)
        ctl.entrysize = sizeof(PrepGeomHashEntry);
        ctl.hash = mcxt_ptr_hasha;
 
-       return hash_create("PostGIS Prepared Geometry Backend MemoryContext Hash", PREPARED_BACKEND_HASH_SIZE, &ctl, (HASH_ELEM | HASH_FUNCTION));
+       PrepGeomHash = hash_create("PostGIS Prepared Geometry Backend MemoryContext Hash", PREPARED_BACKEND_HASH_SIZE, &ctl, (HASH_ELEM | HASH_FUNCTION));
 }
 
 static void 
@@ -3795,15 +3799,27 @@ DeletePrepGeomHashEntry(MemoryContext mcxt)
 **
 */
 PrepGeomCache* 
-GetPrepGeomCache(FunctionCallInfoData *fcinfo, PG_LWGEOM *serialized_geom1, PG_LWGEOM *serialized_geom2, int32 key1, int32 key2)
+GetPrepGeomCache(FunctionCallInfoData *fcinfo, uchar *serialized_geom1, uchar *serialized_geom2)
 {
        PrepGeomCache* cache = fcinfo->flinfo->fn_extra;
+       size_t geom1_size = 0;
+       size_t geom2_size = 0;
 
        if (!PrepGeomHash)
-               PrepGeomHash = CreatePrepGeomHash();
+               CreatePrepGeomHash();
+
+       if(serialized_geom1)
+               geom1_size = lwgeom_size(serialized_geom1);
+               
+       if(serialized_geom2)
+               geom2_size = lwgeom_size(serialized_geom2);
 
        if ( cache == NULL)
        {
+               /*
+               ** Cache hit, but the cache isn't set up yet.
+               ** Set it up, but don't prepare the geometry yet.
+               */
                PrepGeomHashEntry pghe;
                MemoryContext old_context;
        
@@ -3814,8 +3830,10 @@ GetPrepGeomCache(FunctionCallInfoData *fcinfo, PG_LWGEOM *serialized_geom1, PG_L
                cache->prepared_geom = 0;
                cache->geom = 0;
                cache->argnum = 0;
-               cache->key1 = 0;
-               cache->key2 = 0;
+               cache->serialized1 = 0;
+               cache->serialized2 = 0;
+               cache->serialized1_size = 0;
+               cache->serialized2_size = 0;
                cache->context = MemoryContextCreate(T_AllocSetContext, 8192,
                                 &PreparedCacheContextMethods,
                                 fcinfo->flinfo->fn_mcxt,
@@ -3832,12 +3850,17 @@ GetPrepGeomCache(FunctionCallInfoData *fcinfo, PG_LWGEOM *serialized_geom1, PG_L
 
                POSTGIS_DEBUGF(3, "GetPrepGeomCache: adding context to hash: %x", cache);
        }
-       else if ( cache->key1 == key1 )
+       else if ( cache->serialized1_size == geom1_size && 
+                 memcmp(cache->serialized1, serialized_geom1, geom1_size) )
        {
                if ( !cache->prepared_geom )
                {
+                       /*
+                       ** Cache hit, but we haven't prepared our geometry yet.
+                       ** Prepare it.
+                       */
                        PrepGeomHashEntry* pghe;
-                       
+               
                        GEOSGeom g = POSTGIS2GEOS( serialized_geom1 );
                        cache->geom = g;
                        cache->prepared_geom = GEOSPrepare( g );
@@ -3848,38 +3871,50 @@ GetPrepGeomCache(FunctionCallInfoData *fcinfo, PG_LWGEOM *serialized_geom1, PG_L
                        pghe->geom = cache->geom;
                        pghe->prepared_geom = cache->prepared_geom;
                        POSTGIS_DEBUG(3, "GetPrepGeomCache: storing references to prepared obj in argument 1");
-
                }
                else
-               {
+               {       
+                       /*
+                       ** Cache hit, and we're good to go. Do nothing.
+                       */
                        POSTGIS_DEBUG(3, "GetPrepGeomCache: prepared obj 1 in cache");
                }
        }
-       else if ( key2 && cache->key2 == key2 )
+       else if ( cache->serialized2_size == geom2_size && 
+                 memcmp(cache->serialized2, serialized_geom2, geom2_size) )
        {
-               if ( !cache->prepared_geom )
-               {
-                       PrepGeomHashEntry* pghe;
-
-                       GEOSGeom g = POSTGIS2GEOS( serialized_geom2 );
-                       cache->geom = g;
-                       cache->prepared_geom = GEOSPrepare( g );
-                       cache->argnum = 2;
-                       POSTGIS_DEBUG(3, "GetPrepGeomCache: preparing obj in argument 2");
+                       if ( !cache->prepared_geom )
+                       {
+                               /*
+                               ** Cache hit on arg2, but we haven't prepared our geometry yet.
+                               ** Prepare it.
+                               */
+                               PrepGeomHashEntry* pghe;
+                               GEOSGeom g = POSTGIS2GEOS( serialized_geom2 );
+                               cache->geom = g;
+                               cache->prepared_geom = GEOSPrepare( g );
+                               cache->argnum = 2;
+                               POSTGIS_DEBUG(3, "GetPrepGeomCache: preparing obj in argument 2");
                        
-                       pghe = GetPrepGeomHashEntry(cache->context);
-                       pghe->geom = cache->geom;
-                       pghe->prepared_geom = cache->prepared_geom;
-                       POSTGIS_DEBUG(3, "GetPrepGeomCache: storing references to prepared obj in argument 2");
-
-               }
-               else
-               {
-                       POSTGIS_DEBUG(3, "GetPrepGeomCache: prepared obj 2 in cache");
-               }
+                               pghe = GetPrepGeomHashEntry(cache->context);
+                               pghe->geom = cache->geom;
+                               pghe->prepared_geom = cache->prepared_geom;
+                               POSTGIS_DEBUG(3, "GetPrepGeomCache: storing references to prepared obj in argument 2");
+                       }
+                       else 
+                       {
+                               /*
+                               ** Cache hit, and we're good to go. Do nothing.
+                               */
+                               POSTGIS_DEBUG(3, "GetPrepGeomCache: prepared obj for arg 2 in cache");
+                       }
        }
        else if ( cache->prepared_geom )
        {
+               /*
+               ** No cache hits, so this must be a miss.
+               ** Destroy the GEOS objects, empty the cache.
+               */
                PrepGeomHashEntry* pghe;
 
                pghe = GetPrepGeomHashEntry(cache->context);
@@ -3895,9 +3930,17 @@ GetPrepGeomCache(FunctionCallInfoData *fcinfo, PG_LWGEOM *serialized_geom1, PG_L
                cache->argnum = 0;
 
        }
-
-       cache->key1 = key1;
-       cache->key2 = key2;
+       
+       if( serialized_geom1 ) 
+       {
+               cache->serialized1 = serialized_geom1;
+               cache->serialized1_size = geom1_size;
+       }
+       if( serialized_geom2 )
+       { 
+               cache->serialized2 = serialized_geom2;
+               cache->serialized2_size = geom2_size;
+       }
 
        return cache;
 }
@@ -3942,7 +3985,7 @@ Datum containsPrepared(PG_FUNCTION_ARGS)
 
        POSTGIS_DEBUGF(4, "containsPrepared: calling for prep_cache with key1 = %d", key1);
 
-       prep_cache = GetPrepGeomCache( fcinfo, geom1, 0, key1, 0 );
+       prep_cache = GetPrepGeomCache( fcinfo, SERIALIZED_FORM(geom1), 0 );
 
        initGEOS(lwnotice, lwnotice);
 
@@ -4010,7 +4053,7 @@ Datum containsProperlyPrepared(PG_FUNCTION_ARGS)
                        PG_RETURN_BOOL(FALSE);
        }
 
-       prep_cache = GetPrepGeomCache( fcinfo, geom1, 0, key1, 0 );
+       prep_cache = GetPrepGeomCache( fcinfo, SERIALIZED_FORM(geom1), 0 );
 
        initGEOS(lwnotice, lwnotice);
 
@@ -4076,7 +4119,7 @@ Datum coversPrepared(PG_FUNCTION_ARGS)
                        PG_RETURN_BOOL(FALSE);
        }
 
-       prep_cache = GetPrepGeomCache( fcinfo, geom1, 0, key1, 0 );
+       prep_cache = GetPrepGeomCache( fcinfo, SERIALIZED_FORM(geom1), 0 );
 
        initGEOS(lwnotice, lwnotice);
 
@@ -4144,7 +4187,7 @@ Datum intersectsPrepared(PG_FUNCTION_ARGS)
                        PG_RETURN_BOOL(FALSE);
        }
 
-       prep_cache = GetPrepGeomCache( fcinfo, geom1, geom2, key1, key2 );
+       prep_cache = GetPrepGeomCache( fcinfo, SERIALIZED_FORM(geom1), SERIALIZED_FORM(geom2) );
 
        initGEOS(lwnotice, lwnotice);