Refactor from Heikki Linnakangas <heikki@enterprisedb.com>:

* Defined new struct WordEntryPosVector that holds a uint16 length and a
variable size array of WordEntries. This replaces the previous
convention of a variable size uint16 array, with the first element
implying the length. WordEntryPosVector has the same layout in memory,
but is more readable in source code. The POSDATAPTR and POSDATALEN
macros are still used, though it would now be more readable to access
the fields in WordEntryPosVector directly.

* Removed needfree field from DocRepresentation. It was always set to false.

* Miscellaneous other commenting and refactoring

1 files changed, 35 insertions, 33 deletions

diff --git a/src/backend/utils/adt/tsrank.c b/src/backend/utils/adt/tsrank.c
index 535a3541bf7..453b67df431 100644
--- a/src/backend/utils/adt/tsrank.c
+++ b/src/backend/utils/adt/tsrank.c
@@ -7,7 +7,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/adt/tsrank.c,v 1.4 2007/09/07 16:03:40 teodor Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/adt/tsrank.c,v 1.5 2007/09/11 08:46:29 teodor Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -53,22 +53,24 @@ cnt_length(TSVector t)
 {
 	WordEntry  *ptr = ARRPTR(t),
 			   *end = (WordEntry *) STRPTR(t);
-	int			len = 0,
-				clen;
+	int			len = 0;
 
 	while (ptr < end)
 	{
-		if ((clen = POSDATALEN(t, ptr)) == 0)
+		int clen = POSDATALEN(t, ptr);
+
+		if (clen == 0)
 			len += 1;
 		else
 			len += clen;
+
 		ptr++;
 	}
 
 	return len;
 }
 
-static int4
+static int
 WordECompareQueryItem(char *eval, char *qval, WordEntry *ptr, QueryOperand *item)
 {
 	if (ptr->len == item->length)
@@ -80,6 +82,10 @@ WordECompareQueryItem(char *eval, char *qval, WordEntry *ptr, QueryOperand *item
 	return (ptr->len > item->length) ? 1 : -1;
 }
 
+/*
+ * Returns a pointer to a WordEntry corresponding 'item' from tsvector 't'. 'q'
+ * is the TSQuery containing 'item'. Returns NULL if not found.
+ */
 static WordEntry *
 find_wordentry(TSVector t, TSQuery q, QueryOperand *item)
 {
@@ -178,15 +184,15 @@ SortAndUniqItems(TSQuery q, int *size)
 }
 
 /* A dummy WordEntryPos array to use when haspos is false */
-static WordEntryPos POSNULL[] = {
+static WordEntryPosVector POSNULL = {
 	1, /* Number of elements that follow */
-	0
+	{ 0 }
 };
 
 static float
 calc_rank_and(float *w, TSVector t, TSQuery q)
 {
-	uint16	  **pos;
+	WordEntryPosVector	 **pos;
 	int			i,
 				k,
 				l,
@@ -207,9 +213,8 @@ calc_rank_and(float *w, TSVector t, TSQuery q)
 		pfree(item);
 		return calc_rank_or(w, t, q);
 	}
-	pos = (uint16 **) palloc(sizeof(uint16 *) * q->size);
-	memset(pos, 0, sizeof(uint16 *) * q->size);
-	WEP_SETPOS(POSNULL[1], MAXENTRYPOS - 1);
+	pos = (WordEntryPosVector **) palloc0(sizeof(WordEntryPosVector *) * q->size);
+	WEP_SETPOS(POSNULL.pos[0], MAXENTRYPOS - 1);
 
 	for (i = 0; i < size; i++)
 	{
@@ -218,25 +223,25 @@ calc_rank_and(float *w, TSVector t, TSQuery q)
 			continue;
 
 		if (entry->haspos)
-			pos[i] = (uint16 *) _POSDATAPTR(t, entry);
+			pos[i] = _POSVECPTR(t, entry);
 		else
-			pos[i] = (uint16 *) POSNULL;
+			pos[i] = &POSNULL;
 
 
-		dimt = *(uint16 *) (pos[i]);
-		post = (WordEntryPos *) (pos[i] + 1);
+		dimt = pos[i]->npos;
+		post = pos[i]->pos;
 		for (k = 0; k < i; k++)
 		{
 			if (!pos[k])
 				continue;
-			lenct = *(uint16 *) (pos[k]);
-			ct = (WordEntryPos *) (pos[k] + 1);
+			lenct = pos[k]->npos;
+			ct = pos[k]->pos;
 			for (l = 0; l < dimt; l++)
 			{
 				for (p = 0; p < lenct; p++)
 				{
 					dist = Abs((int) WEP_GETPOS(post[l]) - (int) WEP_GETPOS(ct[p]));
-					if (dist || (dist == 0 && (pos[i] == (uint16 *) POSNULL || pos[k] == (uint16 *) POSNULL)))
+					if (dist || (dist == 0 && (pos[i] == &POSNULL || pos[k] == &POSNULL)))
 					{
 						float		curw;
 
@@ -285,8 +290,8 @@ calc_rank_or(float *w, TSVector t, TSQuery q)
 		}
 		else
 		{
-			dimt = *(uint16 *) POSNULL;
-			post = POSNULL + 1;
+			dimt = POSNULL.npos;
+			post = POSNULL.pos;
 		}
 
 		resj = 0.0;
@@ -456,17 +461,19 @@ typedef struct
 {
 	QueryItem **item;
 	int16		nitem;
-	bool		needfree;
 	uint8		wclass;
 	int32		pos;
 } DocRepresentation;
 
 static int
-compareDocR(const void *a, const void *b)
+compareDocR(const void *va, const void *vb)
 {
-	if (((DocRepresentation *) a)->pos == ((DocRepresentation *) b)->pos)
+	DocRepresentation *a = (DocRepresentation *) va;
+	DocRepresentation *b = (DocRepresentation *) vb;
+
+	if (a->pos == b->pos)
 		return 0;
-	return (((DocRepresentation *) a)->pos > ((DocRepresentation *) b)->pos) ? 1 : -1;
+	return (a->pos > b->pos) ? 1 : -1;
 }
 
 static bool
@@ -547,11 +554,11 @@ Cover(DocRepresentation *doc, int len, TSQuery query, Extention *ext)
 
 	ptr = doc + lastpos;
 
-	/* find lower bound of cover from founded upper bound, move down */
+	/* find lower bound of cover from found upper bound, move down */
 	while (ptr >= doc + ext->pos)
 	{
 		for (i = 0; i < ptr->nitem; i++)
-			if(ptr->item[i]->type  == QI_VAL) /* XXX */
+			if(ptr->item[i]->type  == QI_VAL)
 				ptr->item[i]->operand.istrue = 1;
 		if (TS_execute(GETQUERY(query), NULL, true, checkcondition_QueryOperand))
 		{
@@ -620,8 +627,8 @@ get_docrep(TSVector txt, TSQuery query, int *doclen)
 		}
 		else
 		{
-			dimt = *(uint16 *) POSNULL;
-			post = POSNULL + 1;
+			dimt = POSNULL.npos;
+			post = POSNULL.pos;
 		}
 
 		while (cur + dimt >= len)
@@ -636,7 +643,6 @@ get_docrep(TSVector txt, TSQuery query, int *doclen)
 			{
 				int			k;
 
-				doc[cur].needfree = false;
 				doc[cur].nitem = 0;
 				doc[cur].item = (QueryItem **) palloc(sizeof(QueryItem *) * query->size);
 
@@ -658,7 +664,6 @@ get_docrep(TSVector txt, TSQuery query, int *doclen)
 			}
 			else
 			{
-				doc[cur].needfree = false;
 				doc[cur].nitem = doc[cur - 1].nitem;
 				doc[cur].item = doc[cur - 1].item;
 			}
@@ -764,9 +769,6 @@ calc_rank_cd(float4 *arrdata, TSVector txt, TSQuery query, int method)
 	if ((method & RANK_NORM_LOGUNIQ) && txt->size > 0)
 		Wdoc /= log((double) (txt->size + 1)) / log(2.0);
 
-	for (i = 0; i < doclen; i++)
-		if (doc[i].needfree)
-			pfree(doc[i].item);
 	pfree(doc);
 
 	return (float4) Wdoc;