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Protect the game controller API the same way the joystick API is prot…

…ected from multi-threaded access
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slouken committed Dec 8, 2016
1 parent 1b08f0c commit a5250171395eeeb5348be1362afa5f9ab9d7d754
Showing with 43 additions and 11 deletions.
  1. +23 −5 src/joystick/SDL_gamecontroller.c
  2. +17 −6 src/joystick/SDL_joystick.c
  3. +3 −0 src/joystick/SDL_joystick_c.h
@@ -25,6 +25,7 @@
#include "SDL_events.h"
#include "SDL_assert.h"
#include "SDL_sysjoystick.h"
#include "SDL_joystick_c.h"
#include "SDL_hints.h"
#include "SDL_gamecontrollerdb.h"

@@ -1086,12 +1087,15 @@ SDL_GameControllerOpen(int device_index)
return (NULL);
}

SDL_LockJoystickList();

gamecontrollerlist = SDL_gamecontrollers;
/* If the controller is already open, return it */
while (gamecontrollerlist) {
if (SDL_SYS_GetInstanceIdOfDeviceIndex(device_index) == gamecontrollerlist->joystick->instance_id) {
gamecontroller = gamecontrollerlist;
++gamecontroller->ref_count;
SDL_UnlockJoystickList();
return (gamecontroller);
}
gamecontrollerlist = gamecontrollerlist->next;
@@ -1101,20 +1105,23 @@ SDL_GameControllerOpen(int device_index)
pSupportedController = SDL_PrivateGetControllerMapping(device_index);
if (!pSupportedController) {
SDL_SetError("Couldn't find mapping for device (%d)", device_index);
return (NULL);
SDL_UnlockJoystickList();
return NULL;
}

/* Create and initialize the joystick */
gamecontroller = (SDL_GameController *) SDL_malloc((sizeof *gamecontroller));
if (gamecontroller == NULL) {
SDL_OutOfMemory();
SDL_UnlockJoystickList();
return NULL;
}

SDL_memset(gamecontroller, 0, (sizeof *gamecontroller));
gamecontroller->joystick = SDL_JoystickOpen(device_index);
if (!gamecontroller->joystick) {
SDL_free(gamecontroller);
SDL_UnlockJoystickList();
return NULL;
}

@@ -1140,7 +1147,7 @@ SDL_GameControllerOpen(int device_index)
gamecontroller->next = SDL_gamecontrollers;
SDL_gamecontrollers = gamecontroller;

SDL_SYS_JoystickUpdate(gamecontroller->joystick);
SDL_UnlockJoystickList();

return (gamecontroller);
}
@@ -1274,14 +1281,18 @@ SDL_Joystick *SDL_GameControllerGetJoystick(SDL_GameController * gamecontroller)
SDL_GameController *
SDL_GameControllerFromInstanceID(SDL_JoystickID joyid)
{
SDL_GameController *gamecontroller = SDL_gamecontrollers;
SDL_GameController *gamecontroller;

SDL_LockJoystickList();
gamecontroller = SDL_gamecontrollers;
while (gamecontroller) {
if (gamecontroller->joystick->instance_id == joyid) {
SDL_UnlockJoystickList();
return gamecontroller;
}
gamecontroller = gamecontroller->next;
}

SDL_UnlockJoystickList();
return NULL;
}

@@ -1344,8 +1355,11 @@ SDL_GameControllerClose(SDL_GameController * gamecontroller)
if (!gamecontroller)
return;

SDL_LockJoystickList();

/* First decrement ref count */
if (--gamecontroller->ref_count > 0) {
SDL_UnlockJoystickList();
return;
}

@@ -1361,14 +1375,15 @@ SDL_GameControllerClose(SDL_GameController * gamecontroller)
} else {
SDL_gamecontrollers = gamecontroller->next;
}

break;
}
gamecontrollerlistprev = gamecontrollerlist;
gamecontrollerlist = gamecontrollerlist->next;
}

SDL_free(gamecontroller);

SDL_UnlockJoystickList();
}


@@ -1379,10 +1394,13 @@ void
SDL_GameControllerQuit(void)
{
ControllerMapping_t *pControllerMap;

SDL_LockJoystickList();
while (SDL_gamecontrollers) {
SDL_gamecontrollers->ref_count = 1;
SDL_GameControllerClose(SDL_gamecontrollers);
}
SDL_UnlockJoystickList();

while (s_pSupportedControllers) {
pControllerMap = s_pSupportedControllers;
@@ -37,16 +37,16 @@ static SDL_Joystick *SDL_joysticks = NULL;
static SDL_Joystick *SDL_updating_joystick = NULL;
static SDL_mutex *SDL_joystick_lock = NULL; /* This needs to support recursive locks */

static void
SDL_LockJoystickList()
void
SDL_LockJoystickList(void)
{
if (SDL_joystick_lock) {
SDL_LockMutex(SDL_joystick_lock);
}
}

static void
SDL_UnlockJoystickList()
void
SDL_UnlockJoystickList(void)
{
if (SDL_joystick_lock) {
SDL_UnlockMutex(SDL_joystick_lock);
@@ -216,10 +216,10 @@ SDL_JoystickOpen(int device_index)
joystick->next = SDL_joysticks;
SDL_joysticks = joystick;

SDL_SYS_JoystickUpdate(joystick);

SDL_UnlockJoystickList();

SDL_SYS_JoystickUpdate(joystick);

return (joystick);
}

@@ -787,6 +787,12 @@ SDL_JoystickUpdate(void)

SDL_LockJoystickList();

if (SDL_updating_joystick) {
/* The joysticks are already being updated */
SDL_UnlockJoystickList();
return;
}

for (joystick = SDL_joysticks; joystick; joystick = joysticknext) {
/* save off the next pointer, the Update call may cause a joystick removed event
* and cause our joystick pointer to be freed
@@ -795,6 +801,9 @@ SDL_JoystickUpdate(void)

SDL_updating_joystick = joystick;

/* Make sure the list is unlocked while dispatching events to prevent application deadlocks */
SDL_UnlockJoystickList();

SDL_SYS_JoystickUpdate(joystick);

if (joystick->force_recentering) {
@@ -816,6 +825,8 @@ SDL_JoystickUpdate(void)
joystick->force_recentering = SDL_FALSE;
}

SDL_LockJoystickList();

SDL_updating_joystick = NULL;

/* If the joystick was closed while updating, free it here */
@@ -31,6 +31,9 @@ extern void SDL_JoystickQuit(void);
extern int SDL_GameControllerInit(void);
extern void SDL_GameControllerQuit(void);

/* Locking for multi-threaded access to the joystick API */
extern void SDL_LockJoystickList(void);
extern void SDL_UnlockJoystickList(void);

/* Internal event queueing functions */
extern void SDL_PrivateJoystickAdded(int device_index);

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