/* Expands 'hmap', if necessary, to optimize the performance of searches when
* it has up to 'n' elements. (But iteration will be slow in a hash map whose
* allocated capacity is much higher than its current number of nodes.) */
void
hmap_reserve(struct hmap *hmap, size_t n)
{
size_t new_mask = calc_mask(n);
if (new_mask > hmap->mask) {
resize(hmap, new_mask);
}
}
/* Shrinks 'hmap', if necessary, to optimize the performance of iteration. */
void
hmap_shrink(struct hmap *hmap)
{
size_t new_mask = calc_mask(hmap->n);
if (new_mask < hmap->mask) {
resize(hmap, new_mask);
}
}
/* Expands 'hmap', if necessary, to optimize the performance of searches. */
void
hmap_expand(struct hmap *hmap)
{
size_t new_mask = calc_mask(hmap->n);
if (new_mask > hmap->mask) {
resize(hmap, new_mask);
}
}
/* Expands 'hmap', if necessary, to optimize the performance of searches when
* it has up to 'n' elements. (But iteration will be slow in a hash map whose
* allocated capacity is much higher than its current number of nodes.)
*
* ('where' is used in debug logging. Commonly one would use hmap_reserve() to
* automatically provide the caller's source file and line number for
* 'where'.) */
void
hmap_reserve_at(struct hmap *hmap, size_t n, const char *where)
{
size_t new_mask = calc_mask(n);
if (new_mask > hmap->mask) {
COVERAGE_INC(hmap_reserve);
resize(hmap, new_mask, where);
}
}
/* Shrinks 'hmap', if necessary, to optimize the performance of iteration.
*
* ('where' is used in debug logging. Commonly one would use hmap_shrink() to
* automatically provide the caller's source file and line number for
* 'where'.) */
void
hmap_shrink_at(struct hmap *hmap, const char *where)
{
size_t new_mask = calc_mask(hmap->n);
if (new_mask < hmap->mask) {
COVERAGE_INC(hmap_shrink);
resize(hmap, new_mask, where);
}
}
int main(int argc, char **argv)
{
fd_set rdfs;
int s, t;
struct sockaddr_can addr;
struct can_filter rfilter;
struct can_frame frame;
int testcase = 0;
int nbytes, ret;
struct ifreq ifr;
int ifindex;
if ((s = socket(PF_CAN, SOCK_RAW, CAN_RAW)) < 0) {
perror("socket");
return 1;
}
if ((t = socket(PF_CAN, SOCK_RAW, CAN_RAW)) < 0) {
perror("socket");
return 1;
}
strcpy(ifr.ifr_name, "vcan0");
ioctl(s, SIOCGIFINDEX, &ifr);
ifindex = ifr.ifr_ifindex;
addr.can_family = AF_CAN;
addr.can_ifindex = ifindex;
if (bind(s, (struct sockaddr *)&addr, sizeof(addr)) < 0) {
perror("bind");
return 1;
}
if (bind(t, (struct sockaddr *)&addr, sizeof(addr)) < 0) {
perror("bind");
return 1;
}
rfilter.can_id = 0xF; /* receive only the filter requests */
rfilter.can_mask = CAN_SFF_MASK | CAN_EFF_FLAG | CAN_RTR_FLAG;
setsockopt(s, SOL_CAN_RAW, CAN_RAW_FILTER, &rfilter, sizeof(rfilter));
/* disable default receive filter on the test socket */
setsockopt(t, SOL_CAN_RAW, CAN_RAW_FILTER, NULL, 0);
while (1) {
FD_ZERO(&rdfs);
FD_SET(s, &rdfs);
FD_SET(t, &rdfs);
if ((ret = select(t+1, &rdfs, NULL, NULL, NULL)) < 0) {
perror("select");
break;
}
if (FD_ISSET(s, &rdfs)) {
if ((nbytes = read(s, &frame, sizeof(struct can_frame))) < 0) {
perror("read");
exit(1);
}
if (nbytes < sizeof(struct can_frame)) {
fprintf(stderr, "read: incomplete CAN frame\n");
exit(1);
}
if ((frame.can_id != 0xF) || (frame.can_dlc != 1)) {
fprintf(stderr, "\nWrong request from master!\n");
exit(1);
}
testcase = frame.data[0];
if (testcase < 18) {
rfilter.can_id = calc_id(testcase);
rfilter.can_mask = calc_mask(testcase);
setsockopt(t, SOL_CAN_RAW, CAN_RAW_FILTER,
&rfilter, sizeof(rfilter));
printf("testcase %2d : can_id = 0x%08X can_mask = 0x%08X\n",
testcase, rfilter.can_id, rfilter.can_mask);
}
frame.can_id = 0xFA; /* filter ack */
if (write(s, &frame, sizeof(frame)) < 0) {
perror("write");
exit(1);
}
if (testcase > 17)
break;
}
if (FD_ISSET(t, &rdfs)) {
if ((nbytes = read(t, &frame, sizeof(struct can_frame))) < 0) {
perror("read");
exit(1);
}
if (nbytes < sizeof(struct can_frame)) {
fprintf(stderr, "read: incomplete CAN frame\n");
exit(1);
}
printf ("%08X\n", frame.can_id);
}
}
printf("testcase %2d : Filtertest done.\n", testcase);
close(s);
close(t);
return 0;
}
