Cleanup of simple-cache.c. (Bug 172). Allocate less memory when

performing a pattern name match.  
* src/server/simple-cache.c: Removed obsolete comments.  Fixed
spelling errors in comments.
(find_matching_info_compare): Don't overflow if a Conf_no doesn't
fit in an int.
(find_matching_info): Removed obsolete comments (bug 172).
(rebuild_matching_info_entry): Added a comment that explains a
magic "2" in the code.
(build_matching_info): Use cached_no_of_existing_conferences()
instead of next_free_num when deciding how large temporary table
we need.  Reduce the number of loop induction variables.
(cached_lookup_name): Made code more readable by introducing a
temporary variable.

ChangeLog

 2005-12-28  Per Cederqvist  <ceder@lysator.liu.se>
 
+	Cleanup of simple-cache.c.  (Bug 172).  Allocate less memory when
+	performing a pattern name match.  
+	* src/server/simple-cache.c: Removed obsolete comments.  Fixed
+	spelling errors in comments.
+	(find_matching_info_compare): Don't overflow if a Conf_no doesn't
+	fit in an int.
+	(find_matching_info): Removed obsolete comments (bug 172).
+	(rebuild_matching_info_entry): Added a comment that explains a
+	magic "2" in the code.
+	(build_matching_info): Use cached_no_of_existing_conferences()
+	instead of next_free_num when deciding how large temporary table
+	we need.  Reduce the number of loop induction variables.
+	(cached_lookup_name): Made code more readable by introducing a
+	temporary variable.
+
 	Improved test suite logging.
 	* src/server/testsuite/config/unix.exp (simple_expect): Log what
 	we are looking for and when we are done looking at verbosity level

src/server/simple-cache.c

@@ -115,10 +115,6 @@ static Conf_no            existing_confs = 0;
 static Cache_node_mcb 	* text_mcb;
 static Text_no		  next_text_num = 1;
 
-/*
- * The elements in the following lists with same index refers to the same
- * conference.
- */
 static int    no_of_match_info;
 EXPORT Matching_info *match_table = NULL;
 
@@ -1449,7 +1445,7 @@ free_match_table(Matching_info *mtch)
 
 /* Find the entry for CONF_NO in match_table. Return something if
    there is a nonempty name or a list of tokens in the entry. The
-   caller is responsible to checking that the name of the returned
+   caller is responsible for checking that the name of the returned
    entry is nonempty. The reason for this is that cached_delete_conf
    clears the name before rebuilding the matching_info, and
    rebuild_matching_info_entry needs to get the entry to free the
@@ -1462,7 +1458,15 @@ find_matching_info_compare(const void *a, const void *b)
     Matching_info *info_a = (Matching_info *)a;
     Matching_info *info_b = (Matching_info *)b;
 
-    return info_a->conf_no - info_b->conf_no;
+    /* A simple subtraction could be used, but this is more
+       future-proof if we have to increase the size of Conf_no in the
+       future. */
+    if (info_a->conf_no < info_b->conf_no)
+	return -1;
+    else if (info_a->conf_no > info_b->conf_no)
+	return 1;
+    else
+	return 0;
 }
 
 static Matching_info *
@@ -1470,15 +1474,6 @@ find_matching_info(Conf_no conf_no)
 {
     Matching_info   *info, key;
 
-    /* FIXME (bug 172): The comment below, the fact that bsearch() is
-       used, and the comment above find_matching_info_compare() seems
-       to indicate that cleanup is required here.  */
-
-    /* FIXME: Do a binary search here! The search must be able to
-       FIXME: deal with NULL entries. We could do this with a regular
-       FIXME: bearch and a final check that the entry has a non-NULL
-       FIXME: tokens field. */
-
     key.conf_no = conf_no;
     info = bsearch(&key,
                    match_table,
@@ -1582,6 +1577,7 @@ rebuild_matching_info_entry(Conf_no conf_no)
 
         /* Add an entry to the match table */
 
+	/* We need space for the new entry and for the sentinel. */
         match_table = srealloc(match_table, (no_of_match_info + 2) *
                                sizeof(Matching_info));
         match_table[no_of_match_info].name = small_conf_arr[conf_no]->name;
@@ -1605,17 +1601,18 @@ build_matching_info(void)
 {
     Conf_no i;
     Matching_info *mtch;
-    Conf_no	  *conf;
+    Conf_no size;
 
     free_match_table(match_table);
-    
-    match_table = srealloc(match_table, next_free_num * sizeof(Matching_info));
+
+    size = cached_no_of_existing_conferences() + 1;
+    match_table = srealloc(match_table, size * sizeof(Matching_info));
 
     no_of_match_info = 0;
 
     mtch = match_table;
     
-    for ( i = 1; i < next_free_num; i++ )
+    for ( i = 1; i < next_free_num && no_of_match_info < size; i++ )
     {
 	if ( small_conf_arr[ i ] != NULL
 	    && ! s_empty ( small_conf_arr[ i ]->name ) )
@@ -1624,10 +1621,13 @@ build_matching_info(void)
 	    mtch->tokens = tokenize(mtch->name, s_fcrea_str(WHITESPACE));
             mtch->conf_no = i;
 	    ++mtch;
-	    ++conf;
 	    ++no_of_match_info;
 	}
     }
+    if (no_of_match_info >= size)
+	restart_kom("Internal error: build_matching_info: "
+		    "no_of_match_info=%ld but size=%ld\n",
+		    (long)no_of_match_info, (long)size);
 
     mtch->name = EMPTY_STRING;
     mtch->tokens = NULL;
@@ -1645,6 +1645,7 @@ cached_lookup_name(const String name,
 {
     Parse_info tmp;
     int i;
+    Conf_no cno_tmp;
     
     /* FIXME (bug 174): It is a waste of resources to include persons
        here if this lookup is performed due to a lookup-z-name that
@@ -1672,9 +1673,10 @@ cached_lookup_name(const String name,
 	{
 	    if (s_empty(match_table[i].name))
 		continue;
-	    result->conf_nos[result->no_of_conf_nos] = match_table[i].conf_no;
+	    cno_tmp = match_table[i].conf_no;
+	    result->conf_nos[result->no_of_conf_nos] = cno_tmp;
 	    result->type_of_conf[result->no_of_conf_nos] =
-		small_conf_arr[match_table[i].conf_no]->type;
+		small_conf_arr[cno_tmp]->type;
 	    result->no_of_conf_nos++;
 	}
     }
@@ -1688,9 +1690,9 @@ cached_lookup_name(const String name,
 
 	for ( i = 0; i < tmp.no_of_matches; i++ )
 	{
-	    result->conf_nos[ i ] = match_table[ tmp.indexes[ i ] ].conf_no;
-	    result->type_of_conf[ i ]
-		= small_conf_arr[ match_table[ tmp.indexes[ i ] ].conf_no ]->type;
+	    cno_tmp = match_table[ tmp.indexes[i] ].conf_no;
+	    result->conf_nos[i] = cno_tmp;
+	    result->type_of_conf[i] = small_conf_arr[cno_tmp]->type;
 	}
     }		
     sfree(tmp.indexes);