Datum pcpatch_uncompress(PG_FUNCTION_ARGS)
{
SERIALIZED_PATCH *serpa = PG_GETARG_SERPATCH_P(0);
PCSCHEMA *schema = pc_schema_from_pcid(serpa->pcid, fcinfo);
PCPATCH *patch = pc_patch_deserialize(serpa, schema);
SERIALIZED_PATCH *serpa_out = pc_patch_serialize_uncompressed(patch);
pc_patch_free(patch);
PG_RETURN_POINTER(serpa_out);
}
Datum pcpatch_out(PG_FUNCTION_ARGS)
{
PCPATCH *patch = NULL;
SERIALIZED_PATCH *serpatch = NULL;
char *hexwkb = NULL;
PCSCHEMA *schema = NULL;
serpatch = PG_GETARG_SERPATCH_P(0);
schema = pc_schema_from_pcid(serpatch->pcid, fcinfo);
patch = pc_patch_deserialize(serpatch, schema);
hexwkb = pc_patch_to_hexwkb(patch);
pc_patch_free(patch);
PG_RETURN_CSTRING(hexwkb);
}
Datum pcpatch_as_text(PG_FUNCTION_ARGS)
{
SERIALIZED_PATCH *serpatch = PG_GETARG_SERPATCH_P(0);
text *txt;
char *str;
PCSCHEMA *schema = pc_schema_from_pcid(serpatch->pcid, fcinfo);
PCPATCH *patch = pc_patch_deserialize(serpatch, schema);
if ( ! patch )
PG_RETURN_NULL();
str = pc_patch_to_string(patch);
pc_patch_free(patch);
txt = cstring_to_text(str);
pfree(str);
PG_RETURN_TEXT_P(txt);
}
Datum pcpatch_bytea_envelope(PG_FUNCTION_ARGS)
{
SERIALIZED_PATCH *serpatch = PG_GETARG_SERPATCH_P(0);
uint8 *bytes;
size_t bytes_size;
bytea *wkb;
size_t wkb_size;
PCSCHEMA *schema = pc_schema_from_pcid(serpatch->pcid, fcinfo);
PCPATCH *pa = pc_patch_deserialize(serpatch, schema);
if ( ! pa )
PG_RETURN_NULL();
bytes = pc_patch_to_geometry_wkb_envelope(pa, &bytes_size);
wkb_size = VARHDRSZ + bytes_size;
wkb = palloc(wkb_size);
memcpy(VARDATA(wkb), bytes, bytes_size);
SET_VARSIZE(wkb, wkb_size);
pc_patch_free(pa);
pfree(bytes);
PG_RETURN_BYTEA_P(wkb);
}
Datum pcpatch_unnest(PG_FUNCTION_ARGS)
{
typedef struct
{
int nextelem;
int numelems;
PCPOINTLIST *pointlist;
} pcpatch_unnest_fctx;
FuncCallContext *funcctx;
pcpatch_unnest_fctx *fctx;
MemoryContext oldcontext;
/* stuff done only on the first call of the function */
if (SRF_IS_FIRSTCALL())
{
PCPATCH *patch;
SERIALIZED_PATCH *serpatch;
/* create a function context for cross-call persistence */
funcctx = SRF_FIRSTCALL_INIT();
/*
* switch to memory context appropriate for multiple function calls
*/
oldcontext = MemoryContextSwitchTo(funcctx->multi_call_memory_ctx);
/*
* Get the patch value and detoast if needed. We can't do this
* earlier because if we have to detoast, we want the detoasted copy
* to be in multi_call_memory_ctx, so it will go away when we're done
* and not before. (If no detoast happens, we assume the originally
* passed array will stick around till then.)
*/
serpatch = PG_GETARG_SERPATCH_P(0);
patch = pc_patch_deserialize(serpatch, pc_schema_from_pcid_uncached(serpatch->pcid));
/* allocate memory for user context */
fctx = (pcpatch_unnest_fctx *) palloc(sizeof(pcpatch_unnest_fctx));
/* initialize state */
fctx->nextelem = 0;
fctx->numelems = patch->npoints;
fctx->pointlist = pc_pointlist_from_patch(patch);
/* save user context, switch back to function context */
funcctx->user_fctx = fctx;
MemoryContextSwitchTo(oldcontext);
}
/* stuff done on every call of the function */
funcctx = SRF_PERCALL_SETUP();
fctx = funcctx->user_fctx;
if (fctx->nextelem < fctx->numelems)
{
Datum elem;
PCPOINT *pt = pc_pointlist_get_point(fctx->pointlist, fctx->nextelem);
SERIALIZED_POINT *serpt = pc_point_serialize(pt);
fctx->nextelem++;
elem = PointerGetDatum(serpt);
SRF_RETURN_NEXT(funcctx, elem);
}
else
{
/* do when there is no more left */
SRF_RETURN_DONE(funcctx);
}
}
static PCPATCH *
pcpatch_from_patch_array(ArrayType *array, FunctionCallInfoData *fcinfo)
{
int nelems;
bits8 *bitmap;
int bitmask;
size_t offset = 0;
int i;
uint32 pcid = 0;
PCPATCH *pa;
PCPATCH **palist;
int numpatches = 0;
PCSCHEMA *schema = 0;
/* How many things in our array? */
nelems = ArrayGetNItems(ARR_NDIM(array), ARR_DIMS(array));
/* PgSQL supplies a bitmap of which array entries are null */
bitmap = ARR_NULLBITMAP(array);
/* Empty array? Null return */
if ( nelems == 0 )
return NULL;
/* Make our temporary list of patches */
palist = pcalloc(nelems*sizeof(PCPATCH*));
/* Read the patches out of the array and deserialize */
offset = 0;
bitmap = ARR_NULLBITMAP(array);
bitmask = 1;
for ( i = 0; i < nelems; i++ )
{
/* Only work on non-NULL entries in the array */
if ( ! array_get_isnull(bitmap, i) )
{
SERIALIZED_PATCH *serpatch = (SERIALIZED_PATCH *)(ARR_DATA_PTR(array)+offset);
if ( ! schema )
{
schema = pc_schema_from_pcid(serpatch->pcid, fcinfo);
}
if ( ! pcid )
{
pcid = serpatch->pcid;
}
else if ( pcid != serpatch->pcid )
{
elog(ERROR, "pcpatch_from_patch_array: pcid mismatch (%d != %d)", serpatch->pcid, pcid);
}
pa = pc_patch_deserialize(serpatch, schema);
if ( ! pa )
{
elog(ERROR, "pcpatch_from_patch_array: patch deserialization failed");
}
palist[numpatches++] = pa;
offset += INTALIGN(VARSIZE(serpatch));
}
}
/* Can't do anything w/ NULL */
if ( numpatches == 0 )
return NULL;
/* Pass to the lib to build the output patch from the list */
pa = pc_patch_from_patchlist(palist, numpatches);
/* Free the temporary patch list */
for ( i = 0; i < numpatches; i++ )
{
pc_patch_free(palist[i]);
}
pcfree(palist);
return pa;
}
