bitmap: use external iterator

Reuse the Iterator object from hashmap.h and expose a similar API.

This allows us to do

{
    Iterator i;
    unsigned n;

    BITMAP_FOREACH(n, b, i) {
        Iterator j;
        unsigned m;

        BITMAP_FOREACH(m, b, j) {
            ...
        }
    }
}

without getting confused. Requested by David.

2 files changed, 10 insertions, 18 deletions

diff --git a/src/basic/bitmap.c b/src/basic/bitmap.c
index d865e2fc6e..d559be1bbb 100644
--- a/src/basic/bitmap.c
+++ b/src/basic/bitmap.c
@@ -27,7 +27,6 @@ struct Bitmap {
         long long unsigned *bitmaps;
         size_t n_bitmaps;
         size_t bitmaps_allocated;
-        unsigned next_entry;
 };
 
 /* Bitmaps are only meant to store relatively small numbers
@@ -149,22 +148,15 @@ void bitmap_clear(Bitmap *b) {
                 b->bitmaps[i] = 0;
 }
 
-void bitmap_rewind(Bitmap *b) {
-        if (!b)
-                return;
-
-        b->next_entry = 0;
-}
-
-bool bitmap_next(Bitmap *b, unsigned *n) {
+bool bitmap_iterate(Bitmap *b, Iterator *i, unsigned *n) {
         long long bitmask;
         unsigned offset, rem;
 
-        if (!b && b->next_entry == BITMAP_END)
+        if (!b && i->idx == BITMAP_END)
                 return false;
 
-        offset = BITMAP_NUM_TO_OFFSET(b->next_entry);
-        rem = BITMAP_NUM_TO_REM(b->next_entry);
+        offset = BITMAP_NUM_TO_OFFSET(i->idx);
+        rem = BITMAP_NUM_TO_REM(i->idx);
         bitmask = 1 << rem;
 
         for (; offset < b->n_bitmaps; offset ++) {
@@ -172,7 +164,7 @@ bool bitmap_next(Bitmap *b, unsigned *n) {
                         for (; bitmask; bitmask <<= 1, rem ++) {
                                 if (b->bitmaps[offset] & bitmask) {
                                         *n = BITMAP_OFFSET_TO_NUM(offset, rem);
-                                        b->next_entry = *n + 1;
+                                        i->idx = *n + 1;
 
                                         return true;
                                 }
@@ -183,7 +175,7 @@ bool bitmap_next(Bitmap *b, unsigned *n) {
                 bitmask = 1;
         }
 
-        b->next_entry = BITMAP_END;
+        i->idx = BITMAP_END;
 
         return false;
 }
diff --git a/src/basic/bitmap.h b/src/basic/bitmap.h
index 92bee51a2c..2874bc99f7 100644
--- a/src/basic/bitmap.h
+++ b/src/basic/bitmap.h
@@ -22,6 +22,7 @@
 ***/
 
 #include "macro.h"
+#include "hashmap.h"
 
 typedef struct Bitmap Bitmap;
 
@@ -37,13 +38,12 @@ bool bitmap_isset(Bitmap *b, unsigned n);
 bool bitmap_isclear(Bitmap *b);
 void bitmap_clear(Bitmap *b);
 
-void bitmap_rewind(Bitmap *b);
-bool bitmap_next(Bitmap *b, unsigned *n);
+bool bitmap_iterate(Bitmap *b, Iterator *i, unsigned *n);
 
 bool bitmap_equal(Bitmap *a, Bitmap *b);
 
-#define BITMAP_FOREACH(n, b) \
-        for (bitmap_rewind(b); bitmap_next((b), &(n)); )
+#define BITMAP_FOREACH(n, b, i) \
+        for ((i).idx = 0; bitmap_iterate((b), &(i), (unsigned*)&(n)); )
 
 DEFINE_TRIVIAL_CLEANUP_FUNC(Bitmap*, bitmap_free);