From bbc6315ba6b766b9fb39a2d3c0818cf663ed42a4 Mon Sep 17 00:00:00 2001
From: teodor <teodor>
Date: Fri, 11 Jul 2008 10:15:12 +0000
Subject: [PATCH] Add FindOrSavePosition interface for suffix tree

---
 sfxstr.c | 48 ++++++++++++++++++++++++++++++++++++++++++------
 sfxstr.h |  9 +++++++++
 2 files changed, 51 insertions(+), 6 deletions(-)

diff --git a/sfxstr.c b/sfxstr.c
index 0803345..337831c 100644
--- a/sfxstr.c
+++ b/sfxstr.c
@@ -144,21 +144,44 @@ SFSInit_c(SFSTree *info, char **in) {
 
 void*
 SFSFindData(SFSTree *info, char *word, int len) {
+	SFSDataIO	in;
+
+	in.key = word;
+	in.keylen = len;
+
+	return SFSFindDataOrSave(info, &in, NULL);
+}
+
+void*
+SFSFindDataOrSave(SFSTree *info, SFSDataIO *in, SFSTreePosition *position) {
 	SFSNode *node = info->node;
+	SFSNode **pnode = &(info->node);
 	SFSNodeData *StopLow, *StopHigh, *StopMiddle;
-	u_int8_t *ptr =(u_int8_t*)word;
+	u_int8_t *ptr =(u_int8_t*)in->key;
+
+	if ( position ) {
+		position->nodeptr = NULL;
+		position->node = NULL;
+		position->level = 0;
+	}
+
+	while( node && !ISEND(ptr, in->key, in->keylen) ) {
+		if ( position ) {
+			position->nodeptr = pnode;
+			position->node = node;
+			position->level =  ((char*)ptr) - in->key;
+		}
 
-	while( node && !ISEND(ptr, word, len) ) {
 		if ( node->isskip ) {
-		
-			if ( len>0 &&  len - (((char*)ptr) - word) > node->nchar )
+			if ( in->keylen>0 &&  in->keylen - (((char*)ptr) - in->key) > node->nchar )
 				return NULL;
 			else if ( STRNCMP(ptr, ((char*)node)+node->dataptr, node->nchar) ) {
 				ptr+=node->nchar;
-				if ( ISEND(ptr, word, len) && node->isword) {
+				if ( ISEND(ptr, in->key, in->keylen) && node->isword) {
 					return (void*) ( ((char*)(node->data)) + ((node->haschild) ? sizeof(SFSNode*) : 0) );
 				} else if ( node->haschild ) {
 					node = getSkipChildPointer(info, node);
+					pnode = (SFSNode**)( (char*)(node->data) );
 				} else {
 					return NULL;
 				}
@@ -171,10 +194,11 @@ SFSFindData(SFSTree *info, char *word, int len) {
 				StopMiddle = StopLow + ((StopHigh - StopLow) >> 1);
 				if ( StopMiddle->val == *ptr ) {
 					ptr++;
-					if ( ISEND(ptr, word, len) && StopMiddle->isword ) {
+					if ( ISEND(ptr, in->key, in->keylen) && StopMiddle->isword ) {
 						return (void*)( ((char*)node) + node->dataptr + info->datasize * StopMiddle->data );
 					} else if ( StopMiddle->haschild ) {
 						node = getChildPointer(info, StopMiddle);
+						pnode = (SFSNode**)(((char*)StopMiddle) + StopMiddle->child);
 					} else {
 						return NULL;
 					}
@@ -192,6 +216,18 @@ SFSFindData(SFSTree *info, char *word, int len) {
 	return NULL;
 }
 
+void
+SFSAddSaved(SFSTree *info, SFSDataIO *in, SFSTreePosition *position) {
+	CHECK_MEMORY(info);
+
+	if ( !(position->nodeptr && position->node) ) {
+		SFSAdd(info, in);
+		return;
+	}
+
+	*(position->nodeptr) = addRecord(info, position->node, in, position->level);
+}
+
 static void
 freeFSFNode(SFSTree *info, SFSNode *node, void (*freefunc)(void*)) {
 	u_int32_t i;
diff --git a/sfxstr.h b/sfxstr.h
index 22f8410..c49ac24 100644
--- a/sfxstr.h
+++ b/sfxstr.h
@@ -185,6 +185,15 @@ void SFSAdd(SFSTree *info, SFSDataIO *in);
  */
 void* SFSFindData(SFSTree *info, char *word, int len /* optional */ );
 
+typedef struct SFSTreePosition {
+	SFSNode		**nodeptr;
+	SFSNode		 *node;
+	int			  level;
+} SFSTreePosition;
+
+void* SFSFindDataOrSave(SFSTree *info, SFSDataIO *in, SFSTreePosition *position);
+void  SFSAddSaved(SFSTree *info, SFSDataIO *in, SFSTreePosition *position);
+
 /*
  * éÎÉÃÉÁÌÉÚÁÃÉÑ ÉÔÅÒÁÔÏÒÁ × ÎÁÞÁÌÏ ÄÅÒÅ×Á 
  */
-- 
2.37.3