bitvec: Test and fix regression for C++->C conversion
bitvec_read_field/bitvec_write_field in the PCU used a C++ reference
and when porting to C it was decided to pass the parameter by value
and this lost the "back propagation" of the new index. Change the
parameter to be an in/out parameter and this way do not have a silent
semantic break in the osmo-pcu (where we copy the reference in csn.1
by value) and have a true compile failure.
Add Max's simple test for bitvec_unhex function leaving the checking
of bitvec_read_field and the side effect in the datastructure about
the number of bits still open.
diff --git a/src/bitvec.c b/src/bitvec.c
index 46e83f3..b5d2c24 100644
--- a/src/bitvec.c
+++ b/src/bitvec.c
@@ -394,22 +394,22 @@
if (sscanf(src + i, "%1x", &val) < 1) {
return 1;
}
- bitvec_write_field(bv, write_index,val, 4);
+ bitvec_write_field(bv, &write_index, val, 4);
}
return 0;
}
/*! \brief read part of the vector
* \param[in] bv The boolean vector to work on
- * \param[in] read_index Where reading supposed to start in the vector
+ * \param[in,out] read_index Where reading supposed to start in the vector
* \param[in] len How many bits to read from vector
* \returns read bits or negative value on error
*/
-uint64_t bitvec_read_field(struct bitvec *bv, unsigned int read_index, unsigned int len)
+uint64_t bitvec_read_field(struct bitvec *bv, unsigned int *read_index, unsigned int len)
{
unsigned int i;
uint64_t ui = 0;
- bv->cur_bit = read_index;
+ bv->cur_bit = *read_index;
for (i = 0; i < len; i++) {
int bit = bitvec_get_bit_pos((const struct bitvec *)bv, bv->cur_bit);
@@ -419,21 +419,21 @@
ui |= ((uint64_t)1 << (len - i - 1));
bv->cur_bit++;
}
- read_index += len;
+ *read_index += len;
return ui;
}
/*! \brief write into the vector
* \param[in] bv The boolean vector to work on
- * \param[in] write_index Where writing supposed to start in the vector
+ * \param[in,out] write_index Where writing supposed to start in the vector
* \param[in] len How many bits to write
* \returns next write index or negative value on error
*/
-int bitvec_write_field(struct bitvec *bv, unsigned int write_index, uint64_t val, unsigned int len)
+int bitvec_write_field(struct bitvec *bv, unsigned int *write_index, uint64_t val, unsigned int len)
{
unsigned int i;
int rc;
- bv->cur_bit = write_index;
+ bv->cur_bit = *write_index;
for (i = 0; i < len; i++) {
int bit = 0;
if (val & ((uint64_t)1 << (len - i - 1)))
@@ -442,7 +442,7 @@
if (rc)
return rc;
}
- write_index += len;
+ *write_index += len;
return 0;
}