From c417be0f32e0f66e5f0e4a6c3f3224da19f52e4f Mon Sep 17 00:00:00 2001
From: Ralph Ronnquist <ralph.ronnquist@gmail.com>
Date: Wed, 15 Jun 2022 10:06:26 +1000
Subject: [PATCH] corrections

---
 htable/Makefile |  2 +-
 htable/htable.c | 22 +++++++++++-----------
 htable/htable.h |  2 ++
 3 files changed, 14 insertions(+), 12 deletions(-)

diff --git a/htable/Makefile b/htable/Makefile
index 236afb8..4d0ed95 100644
--- a/htable/Makefile
+++ b/htable/Makefile
@@ -1,7 +1,7 @@
 default: libhtable.a
 
 .INTERMEDIATE: htable.o
-htable.o: CFLAGS = -Wall
+htable.o: CFLAGS = -Wall -g
 htable.o: htable.c
 
 libhtable.a: htable.o
diff --git a/htable/htable.c b/htable/htable.c
index c35355d..ce8c838 100644
--- a/htable/htable.c
+++ b/htable/htable.c
@@ -2,8 +2,6 @@
 #include <string.h>
 #include "htable.h"
 
-#define HOLE ((unsigned char *)1)
-
 //// Generic hash table implementation
 
 // Determine the index for a key. On match, it returns the index into
@@ -14,21 +12,23 @@ static int htindex(htable *table,unsigned char *key) {
 	table->data = calloc( 256, sizeof( unsigned char* ) );
 	table->size = 256;
     }
-    unsigned int hash = (*table->hashcode)( table, key ) % table->size;
+    unsigned int hash =
+	( (unsigned int) (*table->hashcode)( table, key ) ) % table->size;
     unsigned int i = hash;
     int hole = -1;
     for ( ;; ) {
-	unsigned char *x = table->data[ i++ ];
+	unsigned char *x = table->data[ i ];
 	if ( x == 0 ) {
-	    return ( hole >= 0 )? -hole : - (int) i;
+	    return ( hole >= 0 )? (- hole - 1 ): ( - (int) i - 1 );
 	}
-	if ( x == HOLE ) {
+	if ( x == HTHOLE ) {
 	    if ( hole < 0 ) {
 		hole = i;
 	    }
 	} else if ( memcmp( x + table->offset, key, table->esize ) == 0 ) {
-	    return i-1;
+	    return i;
 	}
+	i++;
 	if ( i >= table->size ) {
 	    i = 0;
 	}
@@ -36,7 +36,7 @@ static int htindex(htable *table,unsigned char *key) {
 	    break;
 	}
     }
-    return -1;
+    return - hole - 1;
 }
 
 // Find the keyed element, and assign the x pointer, or assign 0.
@@ -89,7 +89,7 @@ static unsigned char *htnext(htable *table,int *i) {
     unsigned char **e = table->data + table->size;
     for ( ; p < e; p++ ) {
 	(*i) += 1;
-	if ( *p != 0 && *p != HOLE ) {
+	if ( *p != 0 && *p != HTHOLE ) {
 	    return *p;
 	}
     }
@@ -127,7 +127,7 @@ void htdelete(htable *table,unsigned char *p) {
     pthread_mutex_lock( &table->lock );
     int i = htindex( table, p + table->offset );
     if ( i >= 0 ) {
-	table->data[ i ] = HOLE;
+	table->data[ i ] = HTHOLE;
 	table->holes += 1;
 	if ( table->holes > table->fill / 2 ) {
 	    htrehash( table, table->size );
@@ -139,7 +139,7 @@ void htdelete(htable *table,unsigned char *p) {
 void htdump(htable *table,void (*dumpitem)(int i,unsigned char *p)) {
     int i;
     for ( i = 0 ; i < table->size; i++ ) {
-	if ( table->data[ i ] && table->data[ i ] != HOLE ) {
+	if ( table->data[ i ] && table->data[ i ] != HTHOLE ) {
 	    dumpitem( i, table->data[ i ] );
 	}
     }
diff --git a/htable/htable.h b/htable/htable.h
index e0233b2..c002dc6 100644
--- a/htable/htable.h
+++ b/htable/htable.h
@@ -71,4 +71,6 @@ void htdump(htable *table,void (*dumpitem)(int i,unsigned char *p));
 	    .esize = sizeof( ((type *)0)->member ), .hashcode = hashcodefn, \
 	    .lock = PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP }
 
+#define HTHOLE ((unsigned char *)1)
+
 #endif // HTABLE_H
-- 
2.39.2