Added src directory

src/ivfutils.c

@@ -0,0 +1,176 @@
+#include "postgres.h"
+
+#include "ivfflat.h"
+#include "storage/bufmgr.h"
+#include "vector.h"
+
+/*
+ * Allocate a vector array
+ */
+VectorArray
+VectorArrayInit(int maxlen, int dimensions)
+{
+	VectorArray res = palloc0(VECTOR_ARRAY_SIZE(maxlen, dimensions));
+
+	res->length = 0;
+	res->maxlen = maxlen;
+	res->dim = dimensions;
+	return res;
+}
+
+/*
+ * Print vector array - useful for debugging
+ */
+void
+PrintVectorArray(char *msg, VectorArray arr)
+{
+	int			i;
+
+	for (i = 0; i < arr->length; i++)
+		PrintVector(msg, VectorArrayGet(arr, i));
+}
+
+/*
+ * Get the number of lists in the index
+ */
+int
+IvfflatGetLists(Relation index)
+{
+	IvfflatOptions *opts = (IvfflatOptions *) index->rd_options;
+
+	if (opts)
+		return opts->lists;
+
+	return IVFFLAT_DEFAULT_LISTS;
+}
+
+/*
+ * Get proc
+ */
+FmgrInfo *
+IvfflatOptionalProcInfo(Relation rel, uint16 procnum)
+{
+	if (!OidIsValid(index_getprocid(rel, 1, procnum)))
+		return NULL;
+
+	return index_getprocinfo(rel, 1, procnum);
+}
+
+/*
+ * Divide by the norm
+ *
+ * Returns false if value should not be indexed
+ *
+ * The caller needs to free the pointer stored in value
+ * if it's different than the original value
+ */
+bool
+IvfflatNormValue(FmgrInfo *procinfo, Oid collation, Datum *value, Vector * result)
+{
+	Vector	   *v;
+	int			i;
+	double		norm;
+
+	norm = DatumGetFloat8(FunctionCall1Coll(procinfo, collation, *value));
+
+	if (norm > 0)
+	{
+		v = (Vector *) DatumGetPointer(*value);
+
+		if (result == NULL)
+			result = InitVector(v->dim);
+
+		for (i = 0; i < v->dim; i++)
+			result->x[i] = v->x[i] / norm;
+
+		*value = PointerGetDatum(result);
+
+		return true;
+	}
+
+	return false;
+}
+
+/*
+ * New buffer
+ */
+Buffer
+IvfflatNewBuffer(Relation index, ForkNumber forkNum)
+{
+	Buffer		buf = ReadBufferExtended(index, forkNum, P_NEW, RBM_NORMAL, NULL);
+
+	LockBuffer(buf, BUFFER_LOCK_EXCLUSIVE);
+	return buf;
+}
+
+/*
+ * Init page
+ */
+void
+IvfflatInitPage(Relation index, Buffer *buf, Page *page, GenericXLogState **state)
+{
+	*state = GenericXLogStart(index);
+	*page = GenericXLogRegisterBuffer(*state, *buf, GENERIC_XLOG_FULL_IMAGE);
+	PageInit(*page, BufferGetPageSize(*buf), sizeof(IvfflatPageOpaqueData));
+	IvfflatPageGetOpaque(*page)->nextblkno = InvalidBlockNumber;
+	IvfflatPageGetOpaque(*page)->page_id = IVFFLAT_PAGE_ID;
+}
+
+/*
+ * Commit buffer
+ */
+void
+IvfflatCommitBuffer(Buffer buf, GenericXLogState *state)
+{
+	MarkBufferDirty(buf);
+	GenericXLogFinish(state);
+	UnlockReleaseBuffer(buf);
+}
+
+/*
+ * Add a new page
+ *
+ * The order is very important!!
+ */
+void
+IvfflatAppendPage(Relation index, Buffer *buf, Page *page, GenericXLogState **state, ForkNumber forkNum)
+{
+	Buffer		prevbuf = *buf;
+
+	/* Get new buffer */
+	*buf = IvfflatNewBuffer(index, forkNum);
+
+	/* Update and commit previous buffer */
+	IvfflatPageGetOpaque(*page)->nextblkno = BufferGetBlockNumber(*buf);
+	IvfflatCommitBuffer(prevbuf, *state);
+
+	/* Init new page */
+	IvfflatInitPage(index, buf, page, state);
+}
+
+/*
+ * Update the start or insert page of a list
+ */
+void
+IvfflatUpdateList(Relation index, GenericXLogState *state, ListInfo listInfo,
+				  BlockNumber insertPage, BlockNumber startPage, ForkNumber forkNum)
+{
+	Buffer		buf;
+	Page		page;
+	IvfflatList list;
+
+	buf = ReadBufferExtended(index, forkNum, listInfo.blkno, RBM_NORMAL, NULL);
+	LockBuffer(buf, BUFFER_LOCK_EXCLUSIVE);
+	state = GenericXLogStart(index);
+	page = GenericXLogRegisterBuffer(state, buf, 0);
+	list = (IvfflatList) PageGetItem(page, PageGetItemId(page, listInfo.offno));
+
+	if (BlockNumberIsValid(insertPage))
+		list->insertPage = insertPage;
+
+	if (BlockNumberIsValid(startPage))
+		list->startPage = startPage;
+
+	/* Could only commit if changed, but extra complexity isn't needed */
+	IvfflatCommitBuffer(buf, state);
+}