377 lines
12 KiB
C++
377 lines
12 KiB
C++
/*
|
|
|
|
Copyright (c) 2017-2019, Feral Interactive
|
|
All rights reserved.
|
|
|
|
Redistribution and use in source and binary forms, with or without
|
|
modification, are permitted provided that the following conditions are met:
|
|
|
|
* Redistributions of source code must retain the above copyright notice,
|
|
this list of conditions and the following disclaimer.
|
|
* 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.
|
|
* Neither the name of Feral Interactive nor the names of its contributors
|
|
may be used to endorse or promote products derived from this software
|
|
without specific prior written permission.
|
|
|
|
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 COPYRIGHT OWNER 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.
|
|
|
|
*/
|
|
#ifndef CLIENT_GAMEMODE_H
|
|
#define CLIENT_GAMEMODE_H
|
|
/*
|
|
* GameMode supports the following client functions
|
|
* Requests are refcounted in the daemon
|
|
*
|
|
* int gamemode_request_start() - Request gamemode starts
|
|
* 0 if the request was sent successfully
|
|
* -1 if the request failed
|
|
*
|
|
* int gamemode_request_end() - Request gamemode ends
|
|
* 0 if the request was sent successfully
|
|
* -1 if the request failed
|
|
*
|
|
* GAMEMODE_AUTO can be defined to make the above two functions apply during static init and
|
|
* destruction, as appropriate. In this configuration, errors will be printed to stderr
|
|
*
|
|
* int gamemode_query_status() - Query the current status of gamemode
|
|
* 0 if gamemode is inactive
|
|
* 1 if gamemode is active
|
|
* 2 if gamemode is active and this client is registered
|
|
* -1 if the query failed
|
|
*
|
|
* int gamemode_request_start_for(pid_t pid) - Request gamemode starts for another process
|
|
* 0 if the request was sent successfully
|
|
* -1 if the request failed
|
|
* -2 if the request was rejected
|
|
*
|
|
* int gamemode_request_end_for(pid_t pid) - Request gamemode ends for another process
|
|
* 0 if the request was sent successfully
|
|
* -1 if the request failed
|
|
* -2 if the request was rejected
|
|
*
|
|
* int gamemode_query_status_for(pid_t pid) - Query status of gamemode for another process
|
|
* 0 if gamemode is inactive
|
|
* 1 if gamemode is active
|
|
* 2 if gamemode is active and this client is registered
|
|
* -1 if the query failed
|
|
*
|
|
* const char* gamemode_error_string() - Get an error string
|
|
* returns a string describing any of the above errors
|
|
*
|
|
* Note: All the above requests can be blocking - dbus requests can and will block while the daemon
|
|
* handles the request. It is not recommended to make these calls in performance critical code
|
|
*/
|
|
|
|
#include <stdbool.h>
|
|
#include <stdio.h>
|
|
|
|
#include <dlfcn.h>
|
|
#include <string.h>
|
|
|
|
#include <assert.h>
|
|
|
|
#include <sys/types.h>
|
|
|
|
static char internal_gamemode_client_error_string[512] = { 0 };
|
|
|
|
/**
|
|
* Load libgamemode dynamically to dislodge us from most dependencies.
|
|
* This allows clients to link and/or use this regardless of runtime.
|
|
* See SDL2 for an example of the reasoning behind this in terms of
|
|
* dynamic versioning as well.
|
|
*/
|
|
static volatile int internal_libgamemode_loaded = 1;
|
|
|
|
/* Typedefs for the functions to load */
|
|
typedef int (*api_call_return_int)(void);
|
|
typedef const char *(*api_call_return_cstring)(void);
|
|
typedef int (*api_call_pid_return_int)(pid_t);
|
|
|
|
/* Storage for functors */
|
|
static api_call_return_int REAL_internal_gamemode_request_start = NULL;
|
|
static api_call_return_int REAL_internal_gamemode_request_end = NULL;
|
|
static api_call_return_int REAL_internal_gamemode_query_status = NULL;
|
|
static api_call_return_cstring REAL_internal_gamemode_error_string = NULL;
|
|
static api_call_pid_return_int REAL_internal_gamemode_request_start_for = NULL;
|
|
static api_call_pid_return_int REAL_internal_gamemode_request_end_for = NULL;
|
|
static api_call_pid_return_int REAL_internal_gamemode_query_status_for = NULL;
|
|
|
|
/**
|
|
* Internal helper to perform the symbol binding safely.
|
|
*
|
|
* Returns 0 on success and -1 on failure
|
|
*/
|
|
__attribute__((always_inline)) static inline int internal_bind_libgamemode_symbol(
|
|
void *handle, const char *name, void **out_func, size_t func_size, bool required)
|
|
{
|
|
void *symbol_lookup = NULL;
|
|
char *dl_error = NULL;
|
|
|
|
/* Safely look up the symbol */
|
|
symbol_lookup = dlsym(handle, name);
|
|
dl_error = dlerror();
|
|
if (required && (dl_error || !symbol_lookup)) {
|
|
snprintf(internal_gamemode_client_error_string,
|
|
sizeof(internal_gamemode_client_error_string),
|
|
"dlsym failed - %s",
|
|
dl_error);
|
|
return -1;
|
|
}
|
|
|
|
/* Have the symbol correctly, copy it to make it usable */
|
|
memcpy(out_func, &symbol_lookup, func_size);
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* Loads libgamemode and needed functions
|
|
*
|
|
* Returns 0 on success and -1 on failure
|
|
*/
|
|
__attribute__((always_inline)) static inline int internal_load_libgamemode(void)
|
|
{
|
|
/* We start at 1, 0 is a success and -1 is a fail */
|
|
if (internal_libgamemode_loaded != 1) {
|
|
return internal_libgamemode_loaded;
|
|
}
|
|
|
|
/* Anonymous struct type to define our bindings */
|
|
struct binding {
|
|
const char *name;
|
|
void **functor;
|
|
size_t func_size;
|
|
bool required;
|
|
} bindings[] = {
|
|
{ "real_gamemode_request_start",
|
|
(void **)&REAL_internal_gamemode_request_start,
|
|
sizeof(REAL_internal_gamemode_request_start),
|
|
true },
|
|
{ "real_gamemode_request_end",
|
|
(void **)&REAL_internal_gamemode_request_end,
|
|
sizeof(REAL_internal_gamemode_request_end),
|
|
true },
|
|
{ "real_gamemode_query_status",
|
|
(void **)&REAL_internal_gamemode_query_status,
|
|
sizeof(REAL_internal_gamemode_query_status),
|
|
false },
|
|
{ "real_gamemode_error_string",
|
|
(void **)&REAL_internal_gamemode_error_string,
|
|
sizeof(REAL_internal_gamemode_error_string),
|
|
true },
|
|
{ "real_gamemode_request_start_for",
|
|
(void **)&REAL_internal_gamemode_request_start_for,
|
|
sizeof(REAL_internal_gamemode_request_start_for),
|
|
false },
|
|
{ "real_gamemode_request_end_for",
|
|
(void **)&REAL_internal_gamemode_request_end_for,
|
|
sizeof(REAL_internal_gamemode_request_end_for),
|
|
false },
|
|
{ "real_gamemode_query_status_for",
|
|
(void **)&REAL_internal_gamemode_query_status_for,
|
|
sizeof(REAL_internal_gamemode_query_status_for),
|
|
false },
|
|
};
|
|
|
|
void *libgamemode = NULL;
|
|
|
|
/* Try and load libgamemode */
|
|
libgamemode = dlopen("libgamemode.so.0", RTLD_NOW);
|
|
if (!libgamemode) {
|
|
/* Attempt to load unversioned library for compatibility with older
|
|
* versions (as of writing, there are no ABI changes between the two -
|
|
* this may need to change if ever ABI-breaking changes are made) */
|
|
libgamemode = dlopen("libgamemode.so", RTLD_NOW);
|
|
if (!libgamemode) {
|
|
snprintf(internal_gamemode_client_error_string,
|
|
sizeof(internal_gamemode_client_error_string),
|
|
"dlopen failed - %s",
|
|
dlerror());
|
|
internal_libgamemode_loaded = -1;
|
|
return -1;
|
|
}
|
|
}
|
|
|
|
/* Attempt to bind all symbols */
|
|
for (size_t i = 0; i < sizeof(bindings) / sizeof(bindings[0]); i++) {
|
|
struct binding *binder = &bindings[i];
|
|
|
|
if (internal_bind_libgamemode_symbol(libgamemode,
|
|
binder->name,
|
|
binder->functor,
|
|
binder->func_size,
|
|
binder->required)) {
|
|
internal_libgamemode_loaded = -1;
|
|
return -1;
|
|
};
|
|
}
|
|
|
|
/* Success */
|
|
internal_libgamemode_loaded = 0;
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* Redirect to the real libgamemode
|
|
*/
|
|
__attribute__((always_inline)) static inline const char *gamemode_error_string(void)
|
|
{
|
|
/* If we fail to load the system gamemode, or we have an error string already, return our error
|
|
* string instead of diverting to the system version */
|
|
if (internal_load_libgamemode() < 0 || internal_gamemode_client_error_string[0] != '\0') {
|
|
return internal_gamemode_client_error_string;
|
|
}
|
|
|
|
/* Assert for static analyser that the function is not NULL */
|
|
assert(REAL_internal_gamemode_error_string != NULL);
|
|
|
|
return REAL_internal_gamemode_error_string();
|
|
}
|
|
|
|
/**
|
|
* Redirect to the real libgamemode
|
|
* Allow automatically requesting game mode
|
|
* Also prints errors as they happen.
|
|
*/
|
|
#ifdef GAMEMODE_AUTO
|
|
__attribute__((constructor))
|
|
#else
|
|
__attribute__((always_inline)) static inline
|
|
#endif
|
|
int gamemode_request_start(void)
|
|
{
|
|
/* Need to load gamemode */
|
|
if (internal_load_libgamemode() < 0) {
|
|
#ifdef GAMEMODE_AUTO
|
|
fprintf(stderr, "gamemodeauto: %s\n", gamemode_error_string());
|
|
#endif
|
|
return -1;
|
|
}
|
|
|
|
/* Assert for static analyser that the function is not NULL */
|
|
assert(REAL_internal_gamemode_request_start != NULL);
|
|
|
|
if (REAL_internal_gamemode_request_start() < 0) {
|
|
#ifdef GAMEMODE_AUTO
|
|
fprintf(stderr, "gamemodeauto: %s\n", gamemode_error_string());
|
|
#endif
|
|
return -1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* Redirect to the real libgamemode */
|
|
#ifdef GAMEMODE_AUTO
|
|
__attribute__((destructor))
|
|
#else
|
|
__attribute__((always_inline)) static inline
|
|
#endif
|
|
int gamemode_request_end(void)
|
|
{
|
|
/* Need to load gamemode */
|
|
if (internal_load_libgamemode() < 0) {
|
|
#ifdef GAMEMODE_AUTO
|
|
fprintf(stderr, "gamemodeauto: %s\n", gamemode_error_string());
|
|
#endif
|
|
return -1;
|
|
}
|
|
|
|
/* Assert for static analyser that the function is not NULL */
|
|
assert(REAL_internal_gamemode_request_end != NULL);
|
|
|
|
if (REAL_internal_gamemode_request_end() < 0) {
|
|
#ifdef GAMEMODE_AUTO
|
|
fprintf(stderr, "gamemodeauto: %s\n", gamemode_error_string());
|
|
#endif
|
|
return -1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* Redirect to the real libgamemode */
|
|
__attribute__((always_inline)) static inline int gamemode_query_status(void)
|
|
{
|
|
/* Need to load gamemode */
|
|
if (internal_load_libgamemode() < 0) {
|
|
return -1;
|
|
}
|
|
|
|
if (REAL_internal_gamemode_query_status == NULL) {
|
|
snprintf(internal_gamemode_client_error_string,
|
|
sizeof(internal_gamemode_client_error_string),
|
|
"gamemode_query_status missing (older host?)");
|
|
return -1;
|
|
}
|
|
|
|
return REAL_internal_gamemode_query_status();
|
|
}
|
|
|
|
/* Redirect to the real libgamemode */
|
|
__attribute__((always_inline)) static inline int gamemode_request_start_for(pid_t pid)
|
|
{
|
|
/* Need to load gamemode */
|
|
if (internal_load_libgamemode() < 0) {
|
|
return -1;
|
|
}
|
|
|
|
if (REAL_internal_gamemode_request_start_for == NULL) {
|
|
snprintf(internal_gamemode_client_error_string,
|
|
sizeof(internal_gamemode_client_error_string),
|
|
"gamemode_request_start_for missing (older host?)");
|
|
return -1;
|
|
}
|
|
|
|
return REAL_internal_gamemode_request_start_for(pid);
|
|
}
|
|
|
|
/* Redirect to the real libgamemode */
|
|
__attribute__((always_inline)) static inline int gamemode_request_end_for(pid_t pid)
|
|
{
|
|
/* Need to load gamemode */
|
|
if (internal_load_libgamemode() < 0) {
|
|
return -1;
|
|
}
|
|
|
|
if (REAL_internal_gamemode_request_end_for == NULL) {
|
|
snprintf(internal_gamemode_client_error_string,
|
|
sizeof(internal_gamemode_client_error_string),
|
|
"gamemode_request_end_for missing (older host?)");
|
|
return -1;
|
|
}
|
|
|
|
return REAL_internal_gamemode_request_end_for(pid);
|
|
}
|
|
|
|
/* Redirect to the real libgamemode */
|
|
__attribute__((always_inline)) static inline int gamemode_query_status_for(pid_t pid)
|
|
{
|
|
/* Need to load gamemode */
|
|
if (internal_load_libgamemode() < 0) {
|
|
return -1;
|
|
}
|
|
|
|
if (REAL_internal_gamemode_query_status_for == NULL) {
|
|
snprintf(internal_gamemode_client_error_string,
|
|
sizeof(internal_gamemode_client_error_string),
|
|
"gamemode_query_status_for missing (older host?)");
|
|
return -1;
|
|
}
|
|
|
|
return REAL_internal_gamemode_query_status_for(pid);
|
|
}
|
|
|
|
#endif // CLIENT_GAMEMODE_H
|