Fix some mistakes in bitfield operations.

1 files changed, 12 insertions, 9 deletions

diff --git a/src/common/bits.c b/src/common/bits.c
index 590c318..a037078 100644
--- a/src/common/bits.c
+++ b/src/common/bits.c
@@ -533,34 +533,35 @@ void or_bit_field_at(bitfield_t *dest, const bitfield_t *src, size_t first)
     size_t start;                           /* Mot de départ dans le champ */
     size_t offset;                          /* Décalage des mots à basculer*/
     size_t remaining;                       /* Taille du dernier tronçon   */
-    unsigned long finalcut;                 /* Limitation du mot final     */
+    size_t last_iter;                       /* Dernière itération à mener  */
     size_t i;                               /* Boucle de parcours          */
     unsigned long word;                     /* Mot reconstituté à tester   */
 
-    assert(dest->length <= (first + src->length));
+    assert((first + src->length) <= dest->length);
 
     start = first / (sizeof(unsigned long) * 8);
     offset = first % (sizeof(unsigned long) * 8);
 
     remaining = (first + src->length) % (sizeof(unsigned long) * 8);
 
-    if (remaining == 0)
-        finalcut = ~0ul;
+    if ((first + src->length) % (sizeof(unsigned long) * 8) > 0)
+        last_iter = src->requested;
     else
-        finalcut = (1ul << remaining) - 1;
+        last_iter = src->requested - 1;
 
-    for (i = 0; i < (src->requested + 1); i++)
+
+    for (i = 0; i <= last_iter; i++)
     {
         if (i < src->requested)
             word = src->bits[i] << offset;
         else
             word = 0;
 
-        if (i > 0)
+        if (i > 0 && offset > 0)
             word |= src->bits[i - 1] >> (sizeof(unsigned long) * 8 - offset);
 
-        if (i == src->requested)
-            word &= finalcut;
+        if (i == last_iter && remaining > 0)
+            word &= (1ul << remaining) - 1;
 
         dest->bits[start + i] |= word;
 
@@ -753,6 +754,8 @@ static bool test_state_within_bit_field(const bitfield_t *field, size_t first, c
 
         test = word ^ bitmask;
 
+        test &= bitmask;
+
         if ((i + 1) == mask->requested)
         {
             bitmask &= finalcut;