From 807b8a9d4deefc4993f4fefc185918ecbef01c9f Mon Sep 17 00:00:00 2001
From: Sam Lantinga <[EMAIL REDACTED]>
Date: Tue, 17 Sep 2024 02:55:23 -0700
Subject: [PATCH] Allow initializing hints and properties from any thread
---
src/SDL.c | 11 +++----
src/SDL_hints.c | 39 +++++++++++++++---------
src/SDL_properties.c | 72 +++++++++++++++++++++++++++++---------------
3 files changed, 77 insertions(+), 45 deletions(-)
diff --git a/src/SDL.c b/src/SDL.c
index d5a12885098a9..0116ba9c30ea5 100644
--- a/src/SDL.c
+++ b/src/SDL.c
@@ -252,21 +252,14 @@ void SDL_InitMainThread(void)
{
SDL_InitTLSData();
SDL_InitEnvironment();
- SDL_InitProperties();
- SDL_InitHints();
SDL_InitTicks();
SDL_InitFilesystem();
- SDL_InitLog();
- SDL_GetGlobalProperties();
}
static void SDL_QuitMainThread(void)
{
- SDL_QuitLog();
SDL_QuitFilesystem();
SDL_QuitTicks();
- SDL_QuitHints();
- SDL_QuitProperties();
SDL_QuitEnvironment();
SDL_QuitTLSData();
}
@@ -625,6 +618,10 @@ void SDL_Quit(void)
*/
SDL_memset(SDL_SubsystemRefCount, 0x0, sizeof(SDL_SubsystemRefCount));
+ SDL_QuitLog();
+ SDL_QuitHints();
+ SDL_QuitProperties();
+
SDL_QuitMainThread();
SDL_bInMainQuit = false;
diff --git a/src/SDL_hints.c b/src/SDL_hints.c
index 8dd9c551ccb09..2d1d5b872a9c9 100644
--- a/src/SDL_hints.c
+++ b/src/SDL_hints.c
@@ -36,20 +36,37 @@ typedef struct SDL_Hint
SDL_HintWatch *callbacks;
} SDL_Hint;
-static SDL_PropertiesID SDL_hint_props = 0;
+static SDL_AtomicU32 SDL_hint_props;
-static SDL_PropertiesID GetHintProperties(bool create)
+
+void SDL_InitHints(void)
+{
+}
+
+void SDL_QuitHints(void)
{
- if (!SDL_hint_props && create) {
- SDL_hint_props = SDL_CreateProperties();
+ SDL_PropertiesID props;
+ do {
+ props = SDL_GetAtomicU32(&SDL_hint_props);
+ } while (!SDL_CompareAndSwapAtomicU32(&SDL_hint_props, props, 0));
+
+ if (props) {
+ SDL_DestroyProperties(props);
}
- return SDL_hint_props;
}
-void SDL_InitHints(void)
+static SDL_PropertiesID GetHintProperties(bool create)
{
- // Just make sure the hint properties are created on the main thread
- (void)GetHintProperties(true);
+ SDL_PropertiesID props = SDL_GetAtomicU32(&SDL_hint_props);
+ if (!props && create) {
+ props = SDL_CreateProperties();
+ if (!SDL_CompareAndSwapAtomicU32(&SDL_hint_props, 0, props)) {
+ // Somebody else created hint properties before us, just use those
+ SDL_DestroyProperties(props);
+ props = SDL_GetAtomicU32(&SDL_hint_props);
+ }
+ }
+ return props;
}
static void SDLCALL CleanupHintProperty(void *userdata, void *value)
@@ -336,9 +353,3 @@ void SDL_RemoveHintCallback(const char *name, SDL_HintCallback callback, void *u
SDL_UnlockProperties(hints);
}
-void SDL_QuitHints(void)
-{
- SDL_DestroyProperties(SDL_hint_props);
- SDL_hint_props = 0;
-}
-
diff --git a/src/SDL_properties.c b/src/SDL_properties.c
index 2a4f2aca83982..eacbc588f4859 100644
--- a/src/SDL_properties.c
+++ b/src/SDL_properties.c
@@ -48,10 +48,11 @@ typedef struct
SDL_Mutex *lock;
} SDL_Properties;
+static SDL_InitState SDL_properties_init;
static SDL_HashTable *SDL_properties;
static SDL_Mutex *SDL_properties_lock;
static SDL_PropertiesID SDL_last_properties_id;
-static SDL_PropertiesID SDL_global_properties;
+static SDL_AtomicU32 SDL_global_properties;
static void SDL_FreePropertyWithCleanup(const void *key, const void *value, void *data, bool cleanup)
@@ -99,27 +100,42 @@ static void SDL_FreeProperties(const void *key, const void *value, void *data)
bool SDL_InitProperties(void)
{
- if (!SDL_properties_lock) {
- SDL_properties_lock = SDL_CreateMutex();
- if (!SDL_properties_lock) {
- return false;
- }
+ if (!SDL_ShouldInit(&SDL_properties_init)) {
+ return true;
}
+
+ // If this fails we'll continue without it.
+ SDL_properties_lock = SDL_CreateMutex();
+
+ SDL_properties = SDL_CreateHashTable(NULL, 16, SDL_HashID, SDL_KeyMatchID, SDL_FreeProperties, false);
if (!SDL_properties) {
- SDL_properties = SDL_CreateHashTable(NULL, 16, SDL_HashID, SDL_KeyMatchID, SDL_FreeProperties, false);
- if (!SDL_properties) {
- return false;
- }
+ goto error;
}
+
+ SDL_SetInitialized(&SDL_properties_init, true);
return true;
+
+error:
+ SDL_SetInitialized(&SDL_properties_init, true);
+ SDL_QuitProperties();
+ return false;
}
void SDL_QuitProperties(void)
{
- if (SDL_global_properties) {
- SDL_DestroyProperties(SDL_global_properties);
- SDL_global_properties = 0;
+ if (!SDL_ShouldQuit(&SDL_properties_init)) {
+ return;
+ }
+
+ SDL_PropertiesID props;
+ do {
+ props = SDL_GetAtomicU32(&SDL_global_properties);
+ } while (!SDL_CompareAndSwapAtomicU32(&SDL_global_properties, props, 0));
+
+ if (props) {
+ SDL_DestroyProperties(props);
}
+
if (SDL_properties) {
SDL_DestroyHashTable(SDL_properties);
SDL_properties = NULL;
@@ -128,14 +144,27 @@ void SDL_QuitProperties(void)
SDL_DestroyMutex(SDL_properties_lock);
SDL_properties_lock = NULL;
}
+
+ SDL_SetInitialized(&SDL_properties_init, false);
+}
+
+static bool SDL_CheckInitProperties(void)
+{
+ return SDL_InitProperties();
}
SDL_PropertiesID SDL_GetGlobalProperties(void)
{
- if (!SDL_global_properties) {
- SDL_global_properties = SDL_CreateProperties();
+ SDL_PropertiesID props = SDL_GetAtomicU32(&SDL_global_properties);
+ if (!props) {
+ props = SDL_CreateProperties();
+ if (!SDL_CompareAndSwapAtomicU32(&SDL_global_properties, 0, props)) {
+ // Somebody else created global properties before us, just use those
+ SDL_DestroyProperties(props);
+ props = SDL_GetAtomicU32(&SDL_global_properties);
+ }
}
- return SDL_global_properties;
+ return props;
}
SDL_PropertiesID SDL_CreateProperties(void)
@@ -144,7 +173,7 @@ SDL_PropertiesID SDL_CreateProperties(void)
SDL_Properties *properties = NULL;
bool inserted = false;
- if (!SDL_properties && !SDL_InitProperties()) {
+ if (!SDL_CheckInitProperties()) {
return 0;
}
@@ -156,14 +185,9 @@ SDL_PropertiesID SDL_CreateProperties(void)
if (!properties->props) {
goto error;
}
- properties->lock = SDL_CreateMutex();
- if (!properties->lock) {
- goto error;
- }
- if (!SDL_InitProperties()) {
- goto error;
- }
+ // If this fails we'll continue without it.
+ properties->lock = SDL_CreateMutex();
SDL_LockMutex(SDL_properties_lock);
++SDL_last_properties_id;