rhashtable: avoid -Wrestrict warning on overlapping sprintf output

sprintf() is declared with a restrict keyword to not allow input and
output to point to the same buffer:

lib/test_rhashtable.c: In function 'print_ht':
lib/test_rhashtable.c:504:4: error: 'sprintf' argument 3 overlaps destination object 'buff' [-Werror=restrict]
  504 |    sprintf(buff, "%s\nbucket[%d] -> ", buff, i);
      |    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
lib/test_rhashtable.c:489:7: note: destination object referenced by 'restrict'-qualified argument 1 was declared here
  489 |  char buff[512] = "";
      |       ^~~~

Rework this function to remember the last offset instead to
avoid the warning.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Arnd Bergmann 2021-03-23 14:03:32 +01:00 committed by David S. Miller
parent b7fbc88692
commit 4adec7f81d

View File

@ -487,6 +487,7 @@ static unsigned int __init print_ht(struct rhltable *rhlt)
struct rhashtable *ht;
const struct bucket_table *tbl;
char buff[512] = "";
int offset = 0;
unsigned int i, cnt = 0;
ht = &rhlt->ht;
@ -501,18 +502,18 @@ static unsigned int __init print_ht(struct rhltable *rhlt)
next = !rht_is_a_nulls(pos) ? rht_dereference(pos->next, ht) : NULL;
if (!rht_is_a_nulls(pos)) {
sprintf(buff, "%s\nbucket[%d] -> ", buff, i);
offset += sprintf(buff + offset, "\nbucket[%d] -> ", i);
}
while (!rht_is_a_nulls(pos)) {
struct rhlist_head *list = container_of(pos, struct rhlist_head, rhead);
sprintf(buff, "%s[[", buff);
offset += sprintf(buff + offset, "[[");
do {
pos = &list->rhead;
list = rht_dereference(list->next, ht);
p = rht_obj(ht, pos);
sprintf(buff, "%s val %d (tid=%d)%s", buff, p->value.id, p->value.tid,
offset += sprintf(buff + offset, " val %d (tid=%d)%s", p->value.id, p->value.tid,
list? ", " : " ");
cnt++;
} while (list);
@ -521,7 +522,7 @@ static unsigned int __init print_ht(struct rhltable *rhlt)
next = !rht_is_a_nulls(pos) ?
rht_dereference(pos->next, ht) : NULL;
sprintf(buff, "%s]]%s", buff, !rht_is_a_nulls(pos) ? " -> " : "");
offset += sprintf(buff + offset, "]]%s", !rht_is_a_nulls(pos) ? " -> " : "");
}
}
printk(KERN_ERR "\n---- ht: ----%s\n-------------\n", buff);