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Cast to `char *' instead of to u_long to help add byte offsets to

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pointers.  Neither is portable, but "correct" casts to integral
types are much uglier - they lead to expressions like

        ptr = (struct struct_with_too_long_a_name *)(void *)(uintptr_t)
	    ((uintptr_t)(void *)ptr + offset);

Here the cast to the struct pointer is to match the surrounding
style of this file (and not depend on C's feature of properly
converting `void *' on assignment or cast), the `void *' casts are
because uintptr_t is only specified to work on `void *' pointers
(I missed this in about 100 lines of previous changes from [u]long
to [u]intptr_t), the outer cast to a uintptr_t is in case the
addition promoted the type, and the inner cast to a uintptr_t
corresponds to the one cast to an integer in the original code.

Don't depend on gcc's feature of casting lvalues.
This commit is contained in:
Bruce Evans 1998-08-15 23:06:38 +00:00
parent 160bd4c62f
commit 7cfd5f54cf
1 changed files with 5 additions and 4 deletions
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9
sys/scsi/ch.c
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@ -33,7 +33,7 @@
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $Id: ch.c,v 1.46 1998/06/07 17:12:47 dfr Exp $
* $Id: ch.c,v 1.47 1998/06/17 14:13:13 bde Exp $
*/
#include "opt_devfs.h"
@ -544,7 +544,7 @@ ch_usergetelemstatus(sc, chet, uptr)
goto done;
st_hdr = (struct read_element_status_header *)data;
pg_hdr = (struct read_element_status_page_header *)((u_long)st_hdr +
pg_hdr = (struct read_element_status_page_header *)((char *)st_hdr +
sizeof(struct read_element_status_header));
desclen = scsi_2btou(pg_hdr->edl);
@ -583,12 +583,13 @@ ch_usergetelemstatus(sc, chet, uptr)
user_data = (u_int8_t *)malloc(avail, M_DEVBUF, M_WAITOK);
desc = (struct read_element_status_descriptor *)((u_long)data +
desc = (struct read_element_status_descriptor *)((char *)data +
sizeof(struct read_element_status_header) +
sizeof(struct read_element_status_page_header));
for (i = 0; i < avail; ++i) {
user_data[i] = desc->flags1;
(u_long)desc += desclen;
desc = (struct read_element_status_descriptor *)
((char *)desc + desclen);
}
/* Copy flags array out to userspace. */