Re: 2.6.36/2.6.37: broken compatibility with userspace input-utils ?

[Mark Lord <kernel@teksavvy.com>]

On 11-01-24 11:20 PM, Dmitry Torokhov wrote:
> On Mon, Jan 24, 2011 at 11:13:05PM -0500, Mark Lord wrote:
>> On 11-01-24 07:55 PM, Dmitry Torokhov wrote:
>>>
>>> No, as far as I know we kept ABI intact.
>>
>>
>> Okay, I hacked lsinput and input-kbd to ignore the protocol number.
>> input-kbd is still broken: it thinks my remote control (Hauppauge)
>> has only ten buttons, and won't allow me to remap codes larger than 10.
>>
>> I've now hacked around that too, but without determining exactly
>> where the interface got broken.
>>
>> Ugh.
>>
>
> Where are the sources? I can take a look...

I used "apt-get source input-utils" under Ubuntu-10.10.
The problem seems to be here somewhere:

static struct kbd_map* kbd_map_read(int fd)
{
        struct kbd_entry entry;
        struct kbd_map *map;
        int rc;

        map = malloc(sizeof(*map));
        memset(map,0,sizeof(*map));
        for (map->size = 0; map->size < 65536; map->size++) {
                entry.scancode = map->size;
                entry.keycode  = KEY_RESERVED;
                rc = ioctl(fd, EVIOCGKEYCODE, &entry);
                if (rc < 0) {
                        break;
                }
                if (map->size >= map->alloc) {
                        map->alloc += 64;
                        map->map = realloc(map->map, map->alloc * sizeof(entry));
                }
                map->map[map->size] = entry;

                if (KEY_RESERVED != entry.keycode)
                        map->keys++;
        }
        if (map->keys) {
                printf("map: %d keys, size: %d/%d\n",
                        map->keys, map->size, map->alloc);
                return map;
        } else {
                free(map);
                return NULL;
        }
}

This results in (map->size==10) for 2.6.36+ (wrong),
and a much larger map->size for 2.6.35 and earlier.

So perhaps EVIOCGKEYCODE has changed?