10 #define alignof(t) offsetof(struct { char c; t x; }, x)
16 struct ioctl_compat_map {
17 int new_req, old_req, old_size;
18 char dir, force_align;
22 static const struct ioctl_compat_map compat_map[] = {
23 { SIOCGSTAMP, SIOCGSTAMP_OLD, 8, R, 0, { 0, -1, -1, -1 } },
24 { SIOCGSTAMPNS, SIOCGSTAMPNS_OLD, 8, R, 0, { 0, -1, -1, -1 } },
27 static void convert_ioctl_struct(const struct ioctl_compat_map *map, char *old, char *new, int dir)
31 int old_size = map->old_size;
32 if (!(dir & map->dir)) return;
33 for (int i=0; i < sizeof map->offsets / sizeof *map->offsets; i++) {
34 int ts_offset = map->offsets[i];
35 if (ts_offset < 0) break;
36 int len = ts_offset-old_offset;
37 if (dir==W) memcpy(old+old_offset, new+new_offset, len);
38 else memcpy(new+new_offset, old+old_offset, len);
43 int align = map->force_align ? sizeof(time_t) : alignof(time_t);
44 new_offset += (align-1) & -new_offset;
46 memcpy(new_ts, new+new_offset, sizeof new_ts);
47 old_ts[0] = new_ts[0];
48 old_ts[1] = new_ts[1];
49 memcpy(old+old_offset, old_ts, sizeof old_ts);
51 memcpy(old_ts, old+old_offset, sizeof old_ts);
52 new_ts[0] = old_ts[0];
53 new_ts[1] = old_ts[1];
54 memcpy(new+new_offset, new_ts, sizeof new_ts);
56 new_offset += sizeof new_ts;
57 old_offset += sizeof old_ts;
59 if (dir==W) memcpy(old+old_offset, new+new_offset, old_size-old_offset);
60 else memcpy(new+new_offset, old+old_offset, old_size-old_offset);
63 int ioctl(int fd, int req, ...)
68 arg = va_arg(ap, void *);
70 int r = __syscall(SYS_ioctl, fd, req, arg);
72 for (int i=0; i<sizeof compat_map/sizeof *compat_map; i++) {
73 if (compat_map[i].new_req != req) continue;
78 convert_ioctl_struct(&compat_map[i], u.buf, arg, W);
79 r = __syscall(SYS_ioctl, fd, compat_map[i].old_req, u.buf);
81 convert_ioctl_struct(&compat_map[i], u.buf, arg, R);
84 return __syscall_ret(r);