Remove code repetition in the doc ID bitmap code.

Remove the repeated "sizeof (doc_ids->bitmap[0])" that bothered cworth
by instead defining macros to compute the word and bit offset of a
given bit in the doc ID set bitmap.

diff --git a/lib/query.cc b/lib/query.cc
index c7ae4ee7afe288a441f1da7574c8b8f167b64b27..c155470afd82128b37a512af892c08b86a1df3a2 100644 (file)
--- a/lib/query.cc
+++ b/lib/query.cc
@@ -41,6 +41,9 @@ struct _notmuch_doc_id_set {
     unsigned int bound;
 };
 
+#define DOCIDSET_WORD(bit) ((bit) / sizeof (unsigned int))
+#define DOCIDSET_BIT(bit) ((bit) % sizeof (unsigned int))
+
 struct _notmuch_threads {
     notmuch_query_t *query;
 
@@ -270,9 +273,8 @@ _notmuch_doc_id_set_init (void *ctx,
     doc_ids->bound = bound;
 
     for (unsigned int i = 0; i < arr->len; i++) {
-       unsigned int doc_id = g_array_index(arr, unsigned int, i);
-       bitmap[doc_id / sizeof (bitmap[0])] |=
-           1 << (doc_id % sizeof (bitmap[0]));
+       unsigned int doc_id = g_array_index (arr, unsigned int, i);
+       bitmap[DOCIDSET_WORD(doc_id)] |= 1 << DOCIDSET_BIT(doc_id);
     }
 
     return TRUE;
@@ -284,8 +286,7 @@ _notmuch_doc_id_set_contains (notmuch_doc_id_set_t *doc_ids,
 {
     if (doc_id >= doc_ids->bound)
        return FALSE;
-    return (doc_ids->bitmap[doc_id / sizeof (doc_ids->bitmap[0])] &
-           (1 << (doc_id % sizeof (doc_ids->bitmap[0])))) != 0;
+    return doc_ids->bitmap[DOCIDSET_WORD(doc_id)] & (1 << DOCIDSET_BIT(doc_id));
 }
 
 void
@@ -293,8 +294,7 @@ _notmuch_doc_id_set_remove (notmuch_doc_id_set_t *doc_ids,
                             unsigned int doc_id)
 {
     if (doc_id < doc_ids->bound)
-       doc_ids->bitmap[doc_id / sizeof (doc_ids->bitmap[0])] &=
-           ~(1 << (doc_id % sizeof (doc_ids->bitmap[0])));
+       doc_ids->bitmap[DOCIDSET_WORD(doc_id)] &= ~(1 << DOCIDSET_BIT(doc_id));
 }
 
 /* Glib objects force use to use a talloc destructor as well, (but not