--- stack/stack.c	2002/01/31 23:09:07	1.17
+++ stack/stack.c	2002/02/01 23:30:55	1.18
@@ -6,6 +6,8 @@
 #include <stddef.h>
 /* dlopen, dlsym, dlerror */
 #include <dlfcn.h>
+/* assert */
+#include <assert.h>
 
 #define HASHTBLSIZE 65536
 
@@ -13,13 +15,14 @@
 {
   enum {
     value,			/* Integer */
-    string, 
-    ref,	    /* Reference (to an element in the hash table) */ 
+    string,
+    ref,			/* Reference (to an element in the
+                                   hash table) */
     func,			/* Function pointer */
     symbol, 
     list
-  } type;			/* Tells what kind of stack element */
-  
+  } type;			/* Type of stack element */
+
   union {
     void* ptr;			/* Pointer to the content */
     int val;			/* ...or an integer */
@@ -31,10 +34,10 @@
 
 
 typedef stackitem* hashtbl[HASHTBLSIZE]; /* Hash table declaration */
-typedef void (*funcp)(stackitem**); /* Function pointer declaration */
-
+typedef void (*funcp)(stackitem**); /* funcp is a pointer to a
+				       void function (stackitem **) */
 
-/* Initiates a newly created hash table. */
+/* Initialize a newly created hash table. */
 void init_hashtbl(hashtbl out_hash)
 {
   long i;
@@ -48,7 +51,7 @@
 {
   long i= 0;
   unsigned long out_hash= 0;
-  char key= 0;
+  char key= '\0';
   stackitem** position;
   
   while(1){			/* Hash in_string */
@@ -61,15 +64,17 @@
   out_hash= out_hash%HASHTBLSIZE;
   position= &(in_hashtbl[out_hash]);
 
-  while(1){			/* Return position if empty */
-    if(*position==NULL)
+  while(position != NULL){
+    if(*position==NULL)		/* If empty */
       return position;
     
-    if(strcmp(in_string, (*position)->id)==0) /* Return position if match */
+    if(strcmp(in_string, (*position)->id)==0) /* If match */
       return position;
 
     position= &((*position)->next); /* Try next */
   }
+  return NULL;			/* end of list reached without finding
+                                   an empty position */
 }
 
 /* Generic push function. */
@@ -84,6 +89,7 @@
 int push_val(stackitem** stack_head, int in_val) 
 {
   stackitem* new_item= malloc(sizeof(stackitem));
+  assert(new_item != NULL);
   new_item->content.val= in_val;
   new_item->type= value;
 
@@ -114,7 +120,7 @@
   return 1;
 }
 
-/* Define a function a new function in the hash table. */
+/* Define a new function in the hash table. */
 void def_func(hashtbl in_hashtbl, funcp in_func, const char* id)
 {
   stackitem* temp= malloc(sizeof(stackitem));