diff options
Diffstat (limited to 'lib/libusbhid/data.c')
| -rw-r--r-- | lib/libusbhid/data.c | 94 |
1 files changed, 94 insertions, 0 deletions
diff --git a/lib/libusbhid/data.c b/lib/libusbhid/data.c new file mode 100644 index 000000000000..31fc0ff587f2 --- /dev/null +++ b/lib/libusbhid/data.c @@ -0,0 +1,94 @@ +/* $NetBSD: data.c,v 1.8 2000/04/02 11:10:53 augustss Exp $ */ + +/* + * Copyright (c) 1999 Lennart Augustsson <augustss@netbsd.org> + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +#include <assert.h> +#include <stdlib.h> +#include "libusb.h" + +int +hid_get_data(const void *p, const hid_item_t *h) +{ + const unsigned char *buf; + unsigned int hpos; + unsigned int hsize; + int data; + int i, end, offs; + + buf = p; + hpos = h->pos; /* bit position of data */ + hsize = h->report_size; /* bit length of data */ + + if (hsize == 0) + return (0); + offs = hpos / 8; + end = (hpos + hsize) / 8 - offs; + data = 0; + for (i = 0; i <= end; i++) + data |= buf[offs + i] << (i*8); + data >>= hpos % 8; + data &= (1 << hsize) - 1; + if (h->logical_minimum < 0) { + /* Need to sign extend */ + hsize = sizeof data * 8 - hsize; + data = (data << hsize) >> hsize; + } + return (data); +} + +void +hid_set_data(void *p, const hid_item_t *h, int data) +{ + unsigned char *buf; + unsigned int hpos; + unsigned int hsize; + int i, end, offs, mask; + + buf = p; + hpos = h->pos; /* bit position of data */ + hsize = h->report_size; /* bit length of data */ + + if (hsize != 32) { + mask = (1 << hsize) - 1; + data &= mask; + } else + mask = ~0; + + data <<= (hpos % 8); + mask <<= (hpos % 8); + mask = ~mask; + + offs = hpos / 8; + end = (hpos + hsize) / 8 - offs; + + for (i = 0; i <= end; i++) + buf[offs + i] = (buf[offs + i] & (mask >> (i*8))) | + ((data >> (i*8)) & 0xff); +} |