Create a function to search for the next set bit in bit field.HEADmaster

1 files changed, 56 insertions, 0 deletions

diff --git a/plugins/pychrysalide/common/bits.c b/plugins/pychrysalide/common/bits.c
index 9275996..a127251 100644
--- a/plugins/pychrysalide/common/bits.c
+++ b/plugins/pychrysalide/common/bits.c
@@ -98,6 +98,9 @@ static PyObject *py_bitfield_test_zeros_with(PyObject *, PyObject *);
 /* Teste l'état à 1 de bits selon un masque de bits. */
 static PyObject *py_bitfield_test_ones_with(PyObject *, PyObject *);
 
+/* Recherche un prochain bit défini dans un champ de bits. */
+static PyObject *py_bitfield_find_next_set(PyObject *, PyObject *);
+
 /* Indique la taille d'un champ de bits donné. */
 static PyObject *py_bitfield_get_size(PyObject *, void *);
 
@@ -891,6 +894,58 @@ static PyObject *py_bitfield_test_ones_with(PyObject *self, PyObject *args)
 
 /******************************************************************************
 *                                                                             *
+*  Paramètres  : self = champ de bits à consulter.                            *
+*                args = arguments fournis pour la conduite de l'opération.    *
+*                                                                             *
+*  Description : Recherche un prochain bit défini dans un champ de bits.      *
+*                                                                             *
+*  Retour      : Position d'un bit à 1 ou taille du champ si plus aucun.      *
+*                                                                             *
+*  Remarques   : -                                                            *
+*                                                                             *
+******************************************************************************/
+
+static PyObject *py_bitfield_find_next_set(PyObject *self, PyObject *args)
+{
+    PyObject *result;                       /* Bilan à faire remonter      */
+    unsigned long prev;                     /* Indice d'un bit à écarter   */
+    int ret;                                /* Bilan de lecture des args.  */
+    py_bitfield_t *bf;                      /* Instance à manipuler        */
+    size_t found;                           /* Indice de bit trouvé        */
+
+#define BITFIELD_FIND_NEXT_SET_METHOD PYTHON_METHOD_DEF     \
+(                                                           \
+    find_next_set, "$self, /, prev=None",                   \
+    METH_VARARGS, py_bitfield,                              \
+    "Find the index of the next set bit in the bit field.\n"\
+    "\n"                                                    \
+    "If provided, the *prev* argument is the position of"   \
+    " a previously found bit, which gets discarded for the" \
+    " current call.\n"                                      \
+    "\n"                                                    \
+    "The result is a integer value: a valid index inside"   \
+    " the bit field, or the bit field size if no set bit"   \
+    " is found."                                            \
+)
+
+    prev = (unsigned long)-1;
+
+    ret = PyArg_ParseTuple(args, "|k", &prev);
+    if (!ret) return NULL;
+
+    bf = (py_bitfield_t *)self;
+
+    found = find_next_set_in_bit_field(bf->native, prev == (unsigned long)-1 ? NULL : (size_t []) { prev });
+
+    result = PyLong_FromSize_t(found);
+
+    return result;
+
+}
+
+
+/******************************************************************************
+*                                                                             *
 *  Paramètres  : self    = classe représentant une instruction.               *
 *                closure = adresse non utilisée ici.                          *
 *                                                                             *
@@ -998,6 +1053,7 @@ PyTypeObject *get_python_bitfield_type(void)
         BITFIELD_TEST_ALL_METHOD,
         BITFIELD_TEST_ZEROS_WITH_METHOD,
         BITFIELD_TEST_ONES_WITH_METHOD,
+        BITFIELD_FIND_NEXT_SET_METHOD,
         { NULL }
     };