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Move 128-bit UUID string parsing to Python; simplify UUID API

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This commit is contained in:
Dan Halbert 2019-01-02 23:11:03 -05:00
parent 87c6f33bcc
commit c46d06f34c
1 changed files with 22 additions and 82 deletions
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92
shared-bindings/bleio/UUID.c
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@ -26,21 +26,13 @@
* THE SOFTWARE.
*/
#include <string.h>
#include "py/objproperty.h"
#include "py/objstr.h"
#include "py/runtime.h"
#include "shared-bindings/bleio/UUID.h"
// Including hyphens.
#define UUID128_STR_LEN 36
// Number of bytes
#define UUID128_BYTE_LEN 16
STATIC uint8_t xdigit_8b_value(byte nibble1, byte nibble2) {
return unichar_xdigit_value(nibble1) | (unichar_xdigit_value(nibble2) << 4);
}
//| .. currentmodule:: bleio
//|
//| :class:`UUID` -- BLE UUID
@ -49,101 +41,49 @@ STATIC uint8_t xdigit_8b_value(byte nibble1, byte nibble2) {
//| A 16-bit or 128-bit UUID. Can be used for services, characteristics, descriptors and more.
//|
//| .. class:: UUID(value, *, base_uuid=None)
//| .. class:: UUID(value)
//|
//| Create a new UUID or UUID object encapsulating the uuid value.
//| The value can be one of:
//|
//| - an `int` value in range 0 to 0xFFFF (Bluetooth SIG 16-bit UUID)
//| - a `str` value in the format 'xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx', where the X's are hex digits.
//| (128 bit UUID)
//| - a buffer object (bytearray, bytes) of 16 bytes in little-endian order (128-bit UUID)
//|
//| :param int/str/buffer value: The uuid value to encapsulate
//|
//| :param int/buffer value: The uuid value to encapsulate
STATIC mp_obj_t bleio_uuid_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *pos_args) {
mp_arg_check_num(n_args, n_kw, 1, 1, true);
mp_arg_check_num(n_args, n_kw, 1, 1, false);
bleio_uuid_obj_t *self = m_new_obj(bleio_uuid_obj_t);
self->base.type = type;
mp_map_t kw_args;
mp_map_init_fixed_table(&kw_args, n_kw, pos_args + n_args);
enum { ARG_value, ARG_base_uuid };
static const mp_arg_t allowed_args[] = {
{ MP_QSTR_value, MP_ARG_REQUIRED | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
{ MP_QSTR_base_uuid, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = mp_const_none} },
};
mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
mp_arg_parse_all(n_args, pos_args, &kw_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args);
const mp_obj_t value = args[ARG_value].u_obj;
const mp_obj_t base_uuid = args[ARG_base_uuid].u_obj;
const mp_obj_t value = pos_args[0];
uint8_t uuid128[16];
if (base_uuid != mp_const_none) {
if (MP_OBJ_IS_TYPE(base_uuid, &bleio_uuid_type)) {
if (!common_hal_bleio_uuid_get_uuid128(base_uuid, uuid128)) {
mp_raise_ValueError(translate("base_uuid is not 128 bits"));
}
} else {
mp_raise_ValueError(translate("base_uuid is not a UUID"));
}
}
if (MP_OBJ_IS_INT(value)) {
mp_int_t uuid16 = mp_obj_get_int(value);
if (uuid16 < 0 || uuid16 > 0xffff) {
mp_raise_ValueError(translate("UUID integer value not in range 0 to 0xffff"));
}
// If a base_uuid was supplied, merge the uuid16 into it. Otherwise
// it's a 16-bit Bluetooth SIG UUID. NULL means no 128-bit value.
common_hal_bleio_uuid_construct(self, uuid16, base_uuid == mp_const_none ? NULL : uuid128);
// NULL means no 128-bit value.
common_hal_bleio_uuid_construct(self, uuid16, NULL);
} else if (MP_OBJ_IS_STR(value)) {
uint8_t uuid128[UUID128_BYTE_LEN];
GET_STR_DATA_LEN(value, str, str_len);
if (str_len == UUID128_STR_LEN &&
str[8] == '-' && str[13] == '-' && str[18] == '-' && str[23] == '-') {
int str_index = UUID128_STR_LEN - 1;
size_t uuid128_index = 0;
bool error = false;
// Loop until fewer than two characters left.
while (str_index >= 1 && uuid128_index < UUID128_BYTE_LEN) {
if (str[str_index] == '-') {
// Skip hyphen separators.
str_index--;
continue;
} else {
mp_buffer_info_t bufinfo;
if (!mp_get_buffer(value, &bufinfo, MP_BUFFER_READ)) {
mp_raise_ValueError(translate("UUID value is not int or byte buffer"));
}
if (!unichar_isxdigit(str[str_index]) ||
!unichar_isxdigit(str[str_index-1])) {
error = true;
break;
if (bufinfo.len != 16) {
mp_raise_ValueError(translate("Byte buffer must be 16 bytes."));
}
uuid128[uuid128_index] = xdigit_8b_value(str[str_index],
str[str_index-1]);
uuid128_index += 1;
str_index -= 2;
}
// Check for correct number of hex digits and no parsing errors.
if (!error && uuid128_index == UUID128_BYTE_LEN && str_index == -1) {
memcpy(uuid128, bufinfo.buf, 16);
uint32_t uuid16 = (uuid128[13] << 8) | uuid128[12];
uuid128[12] = 0;
uuid128[13] = 0;
common_hal_bleio_uuid_construct(self, uuid16, uuid128);
} else {
mp_raise_ValueError(translate("UUID string must be of the form xxxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"));
}
}
} else {
mp_raise_ValueError(translate("UUID value is not int or string"));
common_hal_bleio_uuid_construct(self, uuid16, bufinfo.buf);
}
return MP_OBJ_FROM_PTR(self);