qmk_firmware/quantum/xap/xap.c
2021-08-11 21:08:32 +10:00

116 lines
3.7 KiB
C

/* Copyright 2021 Nick Brassel (@tzarc)
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <quantum.h>
#include <xap.h>
#include <usb_descriptor.h>
#define QSTR2(z) #z
#define QSTR(z) QSTR2(z)
typedef enum xap_route_type_t {
XAP_UNUSED = 0, // "Unused" needs to be zero -- undefined routes (through preprocessor) will be skipped
XAP_ROUTE,
XAP_EXECUTE,
XAP_VALUE,
XAP_GETTER,
XAP_CONST_MEM,
TOTAL_XAP_ROUTE_TYPES
} xap_route_type_t;
#define XAP_ROUTE_TYPE_BIT_COUNT 3
typedef struct __attribute__((packed)) xap_route_flags_t {
xap_route_type_t type : XAP_ROUTE_TYPE_BIT_COUNT;
uint8_t is_secure : 1;
} xap_route_flags_t;
_Static_assert(TOTAL_XAP_ROUTE_TYPES <= (1 << (XAP_ROUTE_TYPE_BIT_COUNT)), "Number of XAP route types is too large for XAP_ROUTE_TYPE_BITS.");
_Static_assert(sizeof(xap_route_flags_t) == 1, "xap_route_flags_t is not length of 1");
typedef struct xap_route_t xap_route_t;
struct __attribute__((packed)) xap_route_t {
const xap_route_flags_t flags;
union {
// XAP_ROUTE
struct {
const xap_route_t *child_routes;
const uint8_t child_routes_len;
};
// XAP_EXECUTE
bool (*handler)(xap_token_t token, const uint8_t *data, size_t data_len);
// XAP_VALUE
uint32_t u32value;
// XAP_GETTER
uint32_t (*u32getter)(void);
// XAP_CONST_MEM
struct {
const void * const_data;
const uint8_t const_data_len;
};
};
};
#include <xap_generated.inl>
void xap_execute_route(xap_token_t token, const xap_route_t *routes, size_t max_routes, const uint8_t *data, size_t data_len) {
if (data_len == 0) return;
xap_identifier_t id = data[0];
if (id < max_routes) {
xap_route_t route;
memcpy_P(&route, &routes[id], sizeof(xap_route_t));
switch (route.flags.type) {
case XAP_ROUTE:
if (route.child_routes != NULL && route.child_routes_len > 0 && data_len > 0) {
xap_execute_route(token, route.child_routes, route.child_routes_len, &data[1], data_len - 1);
return;
}
break;
case XAP_EXECUTE:
if (route.handler != NULL) {
bool ok = (route.handler)(token, data_len == 1 ? NULL : &data[1], data_len - 1);
if (ok) return;
}
break;
case XAP_VALUE:
xap_respond_u32(token, route.u32value);
return;
case XAP_GETTER:
xap_respond_u32(token, (route.u32getter)());
return;
case XAP_CONST_MEM:
xap_respond_data_P(token, route.const_data, route.const_data_len);
return;
default:
break;
}
}
// Nothing got handled, so we respond with failure.
xap_respond_failure(token, XAP_RESPONSE_FLAG_FAILED);
}
void xap_receive(xap_token_t token, const uint8_t *data, size_t length) { xap_execute_route(token, xap_route_table, sizeof(xap_route_table) / sizeof(xap_route_t), data, length); }