X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Fhash.c;h=26e7b6175e1156636511f3f8c5a384c838170db4;hb=6e0c9a99ac662dd811105992a9c9f5f611569590;hp=a94a5495a1e6169271286568bd7908aed9dfafa4;hpb=ce64c0b2eb7f10e4beff695c9bc3f77d0e32604c;p=gnulib.git

diff --git a/lib/hash.c b/lib/hash.c
index a94a5495a..26e7b6175 100644
--- a/lib/hash.c
+++ b/lib/hash.c
@@ -1,5 +1,5 @@
 /* hash - hashing table processing.
-   Copyright (C) 1998, 1999, 2000 Free Software Foundation, Inc.
+   Copyright (C) 1998, 1999, 2000, 2001, 2002 Free Software Foundation, Inc.
    Written by Jim Meyering, 1992.
 
    This program is free software; you can redistribute it and/or modify
@@ -33,7 +33,6 @@
 typedef enum {false = 0, true = 1} bool;
 #endif
 #include <stdio.h>
-#include <assert.h>
 
 #ifndef HAVE_DECL_FREE
 "this configure-time declaration test was not run"
@@ -61,6 +60,40 @@ char *malloc ();
 
 #include "hash.h"
 
+struct hash_table
+  {
+    /* The array of buckets starts at BUCKET and extends to BUCKET_LIMIT-1,
+       for a possibility of N_BUCKETS.  Among those, N_BUCKETS_USED buckets
+       are not empty, there are N_ENTRIES active entries in the table.  */
+    struct hash_entry *bucket;
+    struct hash_entry *bucket_limit;
+    unsigned n_buckets;
+    unsigned n_buckets_used;
+    unsigned n_entries;
+
+    /* Tuning arguments, kept in a physicaly separate structure.  */
+    const Hash_tuning *tuning;
+
+    /* Three functions are given to `hash_initialize', see the documentation
+       block for this function.  In a word, HASHER randomizes a user entry
+       into a number up from 0 up to some maximum minus 1; COMPARATOR returns
+       true if two user entries compare equally; and DATA_FREER is the cleanup
+       function for a user entry.  */
+    Hash_hasher hasher;
+    Hash_comparator comparator;
+    Hash_data_freer data_freer;
+
+    /* A linked list of freed struct hash_entry structs.  */
+    struct hash_entry *free_entry_list;
+
+#if USE_OBSTACK
+    /* Whenever obstacks are used, it is possible to allocate all overflowed
+       entries into a single stack, so they all can be freed in a single
+       operation.  It is not clear if the speedup is worth the trouble.  */
+    struct obstack entry_stack;
+#endif
+  };
+
 /* A hash table contains many internal entries, each holding a pointer to
    some user provided data (also called a user entry).  An entry indistinctly
    refers to both the internal entry and its associated user entry.  A user
@@ -229,7 +262,8 @@ hash_lookup (const Hash_table *table, const void *entry)
     = table->bucket + table->hasher (entry, table->n_buckets);
   struct hash_entry *cursor;
 
-  assert (bucket < table->bucket_limit);
+  if (! (bucket < table->bucket_limit))
+    abort ();
 
   if (bucket->data == NULL)
     return NULL;
@@ -258,12 +292,11 @@ hash_get_first (const Hash_table *table)
   if (table->n_entries == 0)
     return NULL;
 
-  for (bucket = table->bucket; bucket < table->bucket_limit; bucket++)
-    if (bucket->data)
+  for (bucket = table->bucket; ; bucket++)
+    if (! (bucket < table->bucket_limit))
+      abort ();
+    else if (bucket->data)
       return bucket->data;
-
-  assert (0);
-  return NULL;
 }
 
 /* Return the user data for the entry following ENTRY, where ENTRY has been
@@ -277,7 +310,8 @@ hash_get_next (const Hash_table *table, const void *entry)
     = table->bucket + table->hasher (entry, table->n_buckets);
   struct hash_entry *cursor;
 
-  assert (bucket < table->bucket_limit);
+  if (! (bucket < table->bucket_limit))
+    abort ();
 
   /* Find next entry in the same bucket.  */
   for (cursor = bucket; cursor; cursor = cursor->next)
@@ -576,19 +610,22 @@ void
 hash_clear (Hash_table *table)
 {
   struct hash_entry *bucket;
-  struct hash_entry *cursor;
 
   for (bucket = table->bucket; bucket < table->bucket_limit; bucket++)
     {
       if (bucket->data)
 	{
+	  struct hash_entry *cursor;
+	  struct hash_entry *next;
+
 	  /* Free the bucket overflow.  */
-	  for (cursor = bucket->next; cursor; cursor = cursor->next)
+	  for (cursor = bucket->next; cursor; cursor = next)
 	    {
 	      if (table->data_freer)
 		(*table->data_freer) (cursor->data);
 	      cursor->data = NULL;
 
+	      next = cursor->next;
 	      /* Relinking is done one entry at a time, as it is to be expected
 		 that overflows are either rare or short.  */
 	      cursor->next = table->free_entry_list;
@@ -717,7 +754,9 @@ hash_find_entry (Hash_table *table, const void *entry,
     = table->bucket + table->hasher (entry, table->n_buckets);
   struct hash_entry *cursor;
 
-  assert (bucket < table->bucket_limit);
+  if (! (bucket < table->bucket_limit))
+    abort ();
+
   *bucket_head = bucket;
 
   /* Test for empty bucket.  */
@@ -811,7 +850,9 @@ hash_rehash (Hash_table *table, unsigned candidate)
 	    = (new_table->bucket
 	       + new_table->hasher (data, new_table->n_buckets));
 
-	  assert (new_bucket < new_table->bucket_limit);
+	  if (! (new_bucket < new_table->bucket_limit))
+	    abort ();
+
 	  next = cursor->next;
 
 	  if (new_bucket->data)
@@ -875,7 +916,9 @@ hash_insert (Hash_table *table, const void *entry)
   void *data;
   struct hash_entry *bucket;
 
-  assert (entry);		/* cannot insert a NULL entry */
+  /* The caller cannot insert a NULL entry.  */
+  if (! entry)
+    abort ();
 
   /* If there's a matching entry already in the table, return that.  */
   if ((data = hash_find_entry (table, entry, &bucket, false)) != NULL)
@@ -995,13 +1038,14 @@ hash_print (const Hash_table *table)
       struct hash_entry *cursor;
 
       if (bucket)
-	printf ("%d:\n", slot);
+	printf ("%d:\n", bucket - table->bucket);
 
       for (cursor = bucket; cursor; cursor = cursor->next)
 	{
 	  char *s = (char *) cursor->data;
 	  /* FIXME */
-	  printf ("  %s\n", s);
+	  if (s)
+	    printf ("  %s\n", s);
 	}
     }
 }