z_zone: add asserts if zone memory functions are called from non main thread

also taken from srb2classic thanks!

src/CMakeLists.txt

@@ -191,6 +191,7 @@ set(SRB2_CORE_GAME_SOURCES
 	k_kart.c
 	k_stats.c
 	i_time.c
+	i_threads.c
 
 	p_local.h
 	p_maputl.h

src/Makefile.d/dedicated.mk

@@ -8,11 +8,6 @@ ifdef MINGW
 libs+=-mconsole
 endif
 
-ifndef NOTHREADS
-opts+=-DHAVE_THREADS
-sources+=dedicated/i_threads.c
-endif
-
 NOOPENMPT=1
 NOLIBGME=1
 NOHW=1

src/Makefile.d/features.mk

@@ -27,6 +27,11 @@ endif
 sources+=$(call List,hardware/Sourcefile)
 endif
 
+ifndef NOTHREADS
+opts+=-DHAVE_THREADS
+sources+=i_threads.c
+endif
+
 ifndef NOMD5
 sources+=md5.c
 endif

src/Makefile.d/sdl.mk

@@ -40,11 +40,6 @@ sources+=sdl/mixer_sound.c
   endif
 endif
 
-ifndef NOTHREADS
-opts+=-DHAVE_THREADS
-sources+=sdl/i_threads.c
-endif
-
 ifdef SDL_PKGCONFIG
 $(eval $(call Use_pkg_config,SDL))
 else

src/console.c

@@ -44,14 +44,14 @@
 #define MAXHUDLINES 20
 
 #ifdef HAVE_THREADS
-I_mutex con_mutex;
+I_Mutex con_mutex;
 
 // g_in_exiting_signal_handler is an evil hack
 // to avoid infinite SIGABRT recursion in the signal handler
 // due to poisoned locks or mach-o kernel not supporting locks in signals
 // or something like that. idk
-#  define Lock_state()    if (!g_in_exiting_signal_handler) { I_lock_mutex(&con_mutex); }
-#  define Unlock_state()  if (!g_in_exiting_signal_handler) { I_unlock_mutex(con_mutex); }
+#  define Lock_state()    if (!g_in_exiting_signal_handler) { I_LockMutex(&con_mutex); }
+#  define Unlock_state()  if (!g_in_exiting_signal_handler) { I_UnlockMutex(con_mutex); }
 #else/*HAVE_THREADS*/
 #  define Lock_state()
 #  define Unlock_state()

src/console.h

@@ -22,7 +22,7 @@ void CON_Init(void);
 boolean CON_Responder(event_t *ev);
 
 #ifdef HAVE_THREADS
-extern I_mutex con_mutex;
+extern I_Mutex con_mutex;
 #endif
 
 // set true when screen size has changed, to adapt console

src/d_clisrv.c

@@ -2830,11 +2830,11 @@ static boolean CL_ServerConnectionTicker(const char *tmpsave, tic_t *oldtic, tic
 			F_TitleScreenDrawer();
 			CL_DrawConnectionStatus();
 #ifdef HAVE_THREADS
-			I_lock_mutex(&m_menu_mutex);
+			I_LockMutex(&m_menu_mutex);
 #endif
 			M_Drawer(); //Needed for drawing messageboxes on the connection screen
 #ifdef HAVE_THREADS
-			I_unlock_mutex(m_menu_mutex);
+			I_UnlockMutex(m_menu_mutex);
 #endif
 			I_UpdateNoVsync(); // page flip or blit buffer
 			if (moviemode)
@@ -7187,12 +7187,12 @@ void NetUpdate(void)
 	{
 		resptime = nowtime;
 #ifdef HAVE_THREADS
-		I_lock_mutex(&m_menu_mutex);
+		I_LockMutex(&m_menu_mutex);
 #endif
 		M_Ticker();
 		refreshdirmenu = 0;
 #ifdef HAVE_THREADS
-		I_unlock_mutex(m_menu_mutex);
+		I_UnlockMutex(m_menu_mutex);
 #endif
 		CON_Ticker();
 	}

src/d_main.c

@@ -223,13 +223,13 @@ void D_ProcessEvents(void)
 
 		// Menu input
 #ifdef HAVE_THREADS
-		I_lock_mutex(&m_menu_mutex);
+		I_LockMutex(&m_menu_mutex);
 #endif
 		{
 			eaten = M_Responder(ev);
 		}
 #ifdef HAVE_THREADS
-		I_unlock_mutex(m_menu_mutex);
+		I_UnlockMutex(m_menu_mutex);
 #endif
 
 		if (eaten)
@@ -244,13 +244,13 @@ void D_ProcessEvents(void)
 
 		// console input
 #ifdef HAVE_THREADS
-		I_lock_mutex(&con_mutex);
+		I_LockMutex(&con_mutex);
 #endif
 		{
 			eaten = CON_Responder(ev);
 		}
 #ifdef HAVE_THREADS
-		I_unlock_mutex(con_mutex);
+		I_UnlockMutex(con_mutex);
 #endif
 
 		if (eaten)
@@ -577,11 +577,11 @@ static boolean D_Display(void)
 	vid.recalc = false;
 
 #ifdef HAVE_THREADS
-	I_lock_mutex(&m_menu_mutex);
+	I_LockMutex(&m_menu_mutex);
 #endif
 	M_Drawer(); // menu is drawn even on top of everything...
 #ifdef HAVE_THREADS
-	I_unlock_mutex(m_menu_mutex);
+	I_UnlockMutex(m_menu_mutex);
 #endif
 	// focus lost moved to M_Drawer
 

src/d_netfil.c

@@ -112,7 +112,7 @@ static fileused_t transferFiles[UINT8_MAX + 1];
 INT32 fileneedednum = 0; // Number of files needed to join the server
 fileneeded_t fileneeded[MAX_WADFILES] = {}; // List of needed files
 #ifdef HAVE_THREADS
-static I_mutex downloadmutex;
+static I_Mutex downloadmutex;
 #endif
 char downloaddir[512] = "DOWNLOAD";
 
@@ -1427,7 +1427,7 @@ void CURLPrepareFile(const char* url, int dfilenum)
 		filedownload.http_running = true;
 
 #ifdef HAVE_THREADS
-		I_spawn_thread("http-download", (I_thread_fn)CURLGetFile, NULL);
+		(void)!I_SpawnThread("http-download", (I_ThreadFn)CURLGetFile, NULL);
 #endif
 	}
 	else
@@ -1440,15 +1440,15 @@ void CURLAbortFile(void)
 
 #ifdef HAVE_THREADS
 	// lock and unlock to wait for the download thread to exit
-	I_lock_mutex(&downloadmutex);
-	I_unlock_mutex(downloadmutex);
+	I_LockMutex(&downloadmutex);
+	I_UnlockMutex(downloadmutex);
 #endif
 }
 
 static void CURLGetFile(void)
 {
 #ifdef HAVE_THREADS
-	I_lock_mutex(&downloadmutex);
+	I_LockMutex(&downloadmutex);
 #endif
 	CURLMcode mc; /* return code used by curl_multi_wait() */
 	CURLcode easyres; /* Return from easy interface */
@@ -1549,7 +1549,7 @@ static void CURLGetFile(void)
 
 	filedownload.http_running = false;
 #ifdef HAVE_THREADS
-	I_unlock_mutex(downloadmutex);
+	I_UnlockMutex(downloadmutex);
 #endif
 }
 

src/dedicated/Sourcefile

@@ -2,6 +2,5 @@ i_system.c
 i_main.c
 i_video.c
 i_sound.c
-i_threads.c
 dosstr.c
 endtxt.c

src/dedicated/i_system.c

@@ -1381,8 +1381,8 @@ INT32 I_StartupSystem(void)
 		I_Fork();
 #endif
 #ifdef HAVE_THREADS
-	I_start_threads();
-	I_AddExitFunc(I_stop_threads);
+	I_StartThreads();
+	I_AddExitFunc(I_StopThreads);
 #endif
 	I_RegisterSignals();
 #ifndef NOMUMBLE

src/doomtype.h

@@ -223,6 +223,8 @@ typedef int32_t boolean;
 
 	#define FUNCNOINLINE __attribute__((noinline))
 
+	#define FUNCWARNRV __attribute__((warn_unused_result))
+
 	#if (__GNUC__ > 4) || (__GNUC__ == 4 && __GNUC_MINOR__ >= 4) // >= GCC 4.4
 		#ifdef __i386__ // i386 only
 			#define FUNCTARGET(X)  __attribute__ ((__target__ (X)))
@@ -268,6 +270,9 @@ typedef int32_t boolean;
 #ifndef FUNCTARGET
 #define FUNCTARGET(x)
 #endif
+#ifndef FUNCWARNRV
+#define FUNCWARNRV
+#endif
 #ifndef ATTRPACK
 #define ATTRPACK
 #endif

src/f_wipe.c

@@ -388,11 +388,11 @@ void F_RunWipe(UINT8 wipetype, boolean drawMenu)
 		if (rendermode != render_none && drawMenu)
 		{
 #ifdef HAVE_THREADS
-			I_lock_mutex(&m_menu_mutex);
+			I_LockMutex(&m_menu_mutex);
 #endif
 			M_Drawer(); // menu is drawn even on top of wipes
 #ifdef HAVE_THREADS
-			I_unlock_mutex(m_menu_mutex);
+			I_UnlockMutex(m_menu_mutex);
 #endif
 		}
 

src/http-mserv.c

@@ -62,7 +62,7 @@ static int hms_started;
 
 static char *hms_api;
 #ifdef HAVE_THREADS
-static I_mutex hms_api_mutex;
+static I_Mutex hms_api_mutex;
 #endif
 
 static char *hms_server_token;
@@ -90,9 +90,9 @@ Printf_url (const char *url)
 	boolean startup;
 
 #ifdef HAVE_THREADS
-	I_lock_mutex(&con_mutex);
+	I_LockMutex(&con_mutex);
 	startup = con_startup;
-	I_unlock_mutex(con_mutex);
+	I_UnlockMutex(con_mutex);
 #else
 	startup = con_startup;
 #endif
@@ -183,7 +183,7 @@ HMS_connect (const char *format, ...)
 	}
 
 #ifdef HAVE_THREADS
-	I_lock_mutex(&hms_api_mutex);
+	I_LockMutex(&hms_api_mutex);
 #endif
 
 	seek = strlen(hms_api) + 1;/* + '/' */
@@ -195,7 +195,7 @@ HMS_connect (const char *format, ...)
 	sprintf(url, "%s/", hms_api);
 
 #ifdef HAVE_THREADS
-	I_unlock_mutex(hms_api_mutex);
+	I_UnlockMutex(hms_api_mutex);
 #endif
 
 	va_start (ap, format);
@@ -477,12 +477,12 @@ HMS_fetch_servers (msg_server_t *list, int query_id)
 			if (address && port)
 			{
 #ifdef HAVE_THREADS
-				I_lock_mutex(&ms_QueryId_mutex);
+				I_LockMutex(&ms_QueryId_mutex);
 				{
 					if (query_id != ms_QueryId)
 						doing_shit = 0;
 				}
-				I_unlock_mutex(ms_QueryId_mutex);
+				I_UnlockMutex(ms_QueryId_mutex);
 
 				if (! doing_shit)
 					break;
@@ -611,14 +611,14 @@ void
 HMS_set_api (char *api)
 {
 #ifdef HAVE_THREADS
-	I_lock_mutex(&hms_api_mutex);
+	I_LockMutex(&hms_api_mutex);
 #endif
 	{
 		free(hms_api);
 		hms_api = Strip_trailing_slashes(api);
 	}
 #ifdef HAVE_THREADS
-	I_unlock_mutex(hms_api_mutex);
+	I_UnlockMutex(hms_api_mutex);
 #endif
 }
 

src/i_threads.c

@@ -1,4 +1,4 @@
-// SONIC ROBO BLAST 2
+// SONIC ROBO BLAST 2 KART
 //-----------------------------------------------------------------------------
 // Copyright (C) 2020-2023 by James R.
 //
@@ -9,12 +9,14 @@
 /// \file  i_threads.c
 /// \brief Multithreading abstraction
 
-#if defined (__unix__) || (!defined(__APPLE__) && defined (UNIXCOMMON))
+#ifdef HAVE_THREADS
+#if defined (__unix__) || defined(UNIXCOMMON)
 
 #include <pthread.h>
 
-#include "../i_threads.h"
-#include "../doomdef.h"
+#include "i_threads.h"
+#include "doomdef.h"
+#include "doomtype.h"
 
 typedef struct thread_s thread_t;
 
@@ -22,7 +24,7 @@ struct thread_s
 {
 	thread_t *next;
 	void *userdata;
-	I_thread_fn func;
+	I_ThreadFn func;
 	pthread_t thread;
 };
 
@@ -41,12 +43,8 @@ static void *HandleThread(void *data)
 	return NULL;
 }
 
-void
-I_spawn_thread (
-	const char  * name,
-	I_thread_fn   entry,
-	void        * userdata
-)
+FUNCWARNRV
+int I_SpawnThread(const char *name, I_ThreadFn entry, void *userdata)
 {
 	thread_t *thread;
 	(void)name;
@@ -66,17 +64,20 @@ I_spawn_thread (
 	if (thread == NULL)
 	{
 		thread = malloc(sizeof(thread_t));
+		if (thread == NULL)
+			return false;
 		thread->next = thread_list;
 		thread_list = thread;
 	}
 
 	thread->func = entry;
 	thread->userdata = userdata;
-	pthread_create(&thread->thread, NULL, HandleThread, thread);
+	int err = pthread_create(&thread->thread, NULL, HandleThread, thread);
 	pthread_mutex_unlock(&thread_lock);
+	return err == 0;
 }
 
-int I_thread_is_stopped(void)
+int I_ThreadIsStopped(void)
 {
 	thread_t *thread;
 	pthread_mutex_lock(&thread_lock);
@@ -94,11 +95,11 @@ int I_thread_is_stopped(void)
 	return true;
 }
 
-void I_start_threads(void)
+void I_StartThreads(void)
 {
 }
 
-void I_stop_threads(void)
+void I_StopThreads(void)
 {
 	thread_t *thread = thread_list;
 	while (thread != NULL)
@@ -109,7 +110,7 @@ void I_stop_threads(void)
 	}
 }
 
-void I_lock_mutex(I_mutex *anchor)
+void I_LockMutex(I_Mutex *anchor)
 {
 	pthread_mutex_lock(&thread_lock);
 	if (*anchor == NULL)
@@ -127,25 +128,25 @@ void I_lock_mutex(I_mutex *anchor)
 	pthread_mutex_lock(*anchor);
 }
 
-void I_unlock_mutex(I_mutex id)
+void I_UnlockMutex(I_Mutex id)
 {
 	pthread_mutex_unlock(id);
 }
 
-void I_hold_cond(I_cond *cond_anchor, I_mutex mutex_id)
+void I_HoldCond(I_Cond *condAnchor, I_Mutex mutexId)
 {
-	I_Assert(mutex_id != NULL);
+	I_Assert(mutexId != NULL);
 	pthread_mutex_lock(&thread_lock);
-	if (*cond_anchor == NULL)
+	if (*condAnchor == NULL)
 	{
-		*cond_anchor = malloc(sizeof(pthread_cond_t));
-		pthread_cond_init(*cond_anchor, NULL);
+		*condAnchor = malloc(sizeof(pthread_cond_t));
+		pthread_cond_init(*condAnchor, NULL);
 	}
 	pthread_mutex_unlock(&thread_lock);
-	pthread_cond_wait(*cond_anchor, mutex_id);
+	pthread_cond_wait(*condAnchor, mutexId);
 }
 
-void I_wake_one_cond(I_cond *anchor)
+void I_WakeOneCond(I_Cond *anchor)
 {
 	pthread_mutex_lock(&thread_lock);
 	if (*anchor == NULL)
@@ -157,7 +158,7 @@ void I_wake_one_cond(I_cond *anchor)
 	pthread_cond_signal(*anchor);
 }
 
-void I_wake_all_cond(I_cond *anchor)
+void I_WakeAllCond(I_Cond *anchor)
 {
 	pthread_mutex_lock(&thread_lock);
 	if (*anchor == NULL)
@@ -168,12 +169,17 @@ void I_wake_all_cond(I_cond *anchor)
 	pthread_mutex_unlock(&thread_lock);
 	pthread_cond_broadcast(*anchor);
 }
+
+thread_handle_t I_GetCurrentThread(void)
+{
+	return pthread_self();
+}
 #elif defined (_WIN32)
 #include <windows.h>
 
-#include "../i_threads.h"
-#include "../doomdef.h"
-#include "../doomtype.h"
+#include "i_threads.h"
+#include "doomdef.h"
+#include "doomtype.h"
 
 typedef struct thread_s thread_t;
 
@@ -181,9 +187,9 @@ struct thread_s
 {
 	thread_t *next;
 	void *userdata;
-	I_thread_fn func;
+	I_ThreadFn func;
 	HANDLE thread;
-	DWORD thread_id;
+	DWORD threadId;
 };
 
 // we use a linked list to avoid moving memory blocks when allocating new threads.
@@ -201,7 +207,8 @@ static DWORD __stdcall HandleThread(void *data)
 	return 0;
 }
 
-void I_spawn_thread(const char *name, I_thread_fn entry, void *userdata)
+FUNCWARNRV
+int I_SpawnThread(const char *name, I_ThreadFn entry, void *userdata)
 {
 	thread_t *thread;
 	(void)name;
@@ -219,17 +226,20 @@ void I_spawn_thread(const char *name, I_thread_fn entry, void *userdata)
 	if (thread == NULL)
 	{
 		thread = malloc(sizeof(thread_t));
+		if (thread == NULL)
+			return false;
 		thread->next = thread_list;
 		thread_list = thread;
 	}
 
 	thread->func = entry;
 	thread->userdata = userdata;
-	thread->thread = CreateThread(NULL, 0, HandleThread, thread, 0, &thread->thread_id);
+	thread->thread = CreateThread(NULL, 0, HandleThread, thread, 0, &thread->threadId);
 	LeaveCriticalSection(&thread_lock);
+	return thread->thread != NULL;
 }
 
-int I_thread_is_stopped(void)
+int I_ThreadIsStopped(void)
 {
 	thread_t *thread;
 	EnterCriticalSection(&thread_lock);
@@ -247,12 +257,12 @@ int I_thread_is_stopped(void)
 	return true;
 }
 
-void I_start_threads(void)
+void I_StartThreads(void)
 {
 	InitializeCriticalSection(&thread_lock);
 }
 
-void I_stop_threads(void)
+void I_StopThreads(void)
 {
 	thread_t *thread = thread_list;
 	while (thread != NULL)
@@ -264,7 +274,7 @@ void I_stop_threads(void)
 	DeleteCriticalSection(&thread_lock);
 }
 
-void I_lock_mutex(I_mutex *anchor)
+void I_LockMutex(I_Mutex *anchor)
 {
 	EnterCriticalSection(&thread_lock);
 	if (*anchor == NULL)
@@ -276,25 +286,25 @@ void I_lock_mutex(I_mutex *anchor)
 	EnterCriticalSection(*anchor);
 }
 
-void I_unlock_mutex(I_mutex id)
+void I_UnlockMutex(I_Mutex id)
 {
 	LeaveCriticalSection(id);
 }
 
-void I_hold_cond(I_cond *cond_anchor, I_mutex mutex_id)
+void I_HoldCond(I_Cond *condAnchor, I_Mutex mutexId)
 {
-	I_Assert(mutex_id != NULL);
+	I_Assert(mutexId != NULL);
 	EnterCriticalSection(&thread_lock);
-	if (*cond_anchor == NULL)
+	if (*condAnchor == NULL)
 	{
-		*cond_anchor = malloc(sizeof(CONDITION_VARIABLE));
-		InitializeConditionVariable(*cond_anchor);
+		*condAnchor = malloc(sizeof(CONDITION_VARIABLE));
+		InitializeConditionVariable(*condAnchor);
 	}
 	LeaveCriticalSection(&thread_lock);
-	SleepConditionVariableCS(*cond_anchor, mutex_id, INFINITE);
+	SleepConditionVariableCS(*condAnchor, mutexId, INFINITE);
 }
 
-void I_wake_one_cond(I_cond *anchor)
+void I_WakeOneCond(I_Cond *anchor)
 {
 	EnterCriticalSection(&thread_lock);
 	if (*anchor == NULL)
@@ -306,7 +316,7 @@ void I_wake_one_cond(I_cond *anchor)
 	WakeConditionVariable(*anchor);
 }
 
-void I_wake_all_cond(I_cond *anchor)
+void I_WakeAllCond(I_Cond *anchor)
 {
 	EnterCriticalSection(&thread_lock);
 	if (*anchor == NULL)
@@ -317,48 +327,66 @@ void I_wake_all_cond(I_cond *anchor)
 	LeaveCriticalSection(&thread_lock);
 	WakeAllConditionVariable(*anchor);
 }
+
+void *I_GetCurrentThread(void)
+{
+	return GetCurrentThread();
+}
 #else
-void I_spawn_thread(const char *name, I_thread_fn entry, void *userdata)
+#include "i_threads.h"
+
+FUNCWARNRV
+int I_SpawnThread(const char *name, I_ThreadFn entry, void *userdata)
 {
 	(void)name;
 	entry(userdata);
+	return true;
 }
 
-int I_thread_is_stopped(void)
+int I_ThreadIsStopped(void)
+{
+	return true;
+}
+
+void I_StartThreads(void)
 {
 }
 
-void I_start_threads(void)
+void I_StopThreads(void)
 {
 }
 
-void I_stop_threads(void)
-{
-}
-
-void I_lock_mutex(I_mutex *anchor)
+void I_LockMutex(I_Mutex *anchor)
 {
 	(void)anchor;
 }
 
-void I_unlock_mutex(I_mutex id)
+void I_UnlockMutex(I_Mutex id)
 {
 	(void)id;
 }
 
-void I_hold_cond(I_cond *cond_anchor, I_mutex mutex_id)
+void I_HoldCond(I_Cond *condAnchor, I_Mutex mutexId)
 {
-	(void)cond_anchor;
-	(void)mutex_id;
+	(void)condAnchor;
+	(void)mutexId;
 }
 
-void I_wake_one_cond(I_cond *anchor)
+void I_WakeOneCond(I_Cond *anchor)
 {
 	(void)anchor;
 }
 
-void I_wake_all_cond(I_cond *anchor)
+void I_WakeAllCond(I_Cond *anchor)
 {
 	(void)anchor;
 }
+
+void *I_GetCurrentThread(void)
+{
+	return NULL;
+}
 #endif
+
+
+#endif // HAVE_THREADS

src/i_threads.h

@@ -1,6 +1,6 @@
 // SONIC ROBO BLAST 2 KART
 //-----------------------------------------------------------------------------
-// Copyright (C) 2020 by James R.
+// Copyright (C) 2020-2023 by James R.
 //
 // This program is free software distributed under the
 // terms of the GNU General Public License, version 2.
@@ -14,34 +14,46 @@
 #ifndef I_THREADS_H
 #define I_THREADS_H
 
+#include "doomtype.h"
+
 #ifdef __cplusplus
 extern "C" {
 #endif
 
-typedef void (*I_thread_fn)(void *userdata);
+typedef void (*I_ThreadFn)(void *userdata);
 
-typedef void * I_mutex;
-typedef void * I_cond;
+typedef void * I_Mutex;
+typedef void * I_Cond;
 
-void      I_start_threads (void);
-void      I_stop_threads  (void);
+#ifdef __linux__
+typedef long unsigned int thread_handle_t;
+#else
+typedef void *thread_handle_t;
+#endif
 
-void      I_spawn_thread (const char *name, I_thread_fn, void *userdata);
+void      I_StartThreads (void);
+void      I_StopThreads  (void);
+
+FUNCWARNRV
+int       I_SpawnThread (const char *name, I_ThreadFn, void *userdata);
 
 /* check in your thread whether to return early */
-int       I_thread_is_stopped (void);
+int       I_ThreadIsStopped (void);
 
-void      I_lock_mutex      (I_mutex *);
-void      I_unlock_mutex    (I_mutex);
+void      I_LockMutex      (I_Mutex *);
+void      I_UnlockMutex    (I_Mutex);
 
-void      I_hold_cond       (I_cond *, I_mutex);
+void      I_HoldCond       (I_Cond *, I_Mutex);
 
-void      I_wake_one_cond   (I_cond *);
-void      I_wake_all_cond   (I_cond *);
+void      I_WakeOneCond   (I_Cond *);
+void      I_WakeAllCond   (I_Cond *);
+
+thread_handle_t I_GetCurrentThread(void);
 
 #ifdef __cplusplus
 } // extern "C"
 #endif
 
 #endif/*I_THREADS_H*/
+
 #endif/*HAVE_THREADS*/

src/m_menu.c

@@ -142,7 +142,7 @@ typedef enum
 } text_enum;
 
 #ifdef HAVE_THREADS
-I_mutex m_menu_mutex;
+I_Mutex m_menu_mutex;
 #endif
 
 M_waiting_mode_t m_waiting_mode = M_NOT_WAITING;
@@ -1967,7 +1967,7 @@ void M_Ticker(void)
 	}
 
 #if defined (MASTERSERVER) && defined (HAVE_THREADS)
-	I_lock_mutex(&ms_ServerList_mutex);
+	I_LockMutex(&ms_ServerList_mutex);
 	{
 		if (ms_ServerList)
 		{
@@ -1976,7 +1976,7 @@ void M_Ticker(void)
 			ms_ServerList = NULL;
 		}
 	}
-	I_unlock_mutex(ms_ServerList_mutex);
+	I_UnlockMutex(ms_ServerList_mutex);
 #endif
 }
 
@@ -4014,14 +4014,14 @@ size_t demolist_all_size = 0;
 boolean replaynamesloaded = false;
 
 #ifdef HAVE_THREADS
-I_mutex replayquerymutex;
+I_Mutex replayquerymutex;
 
 // g_in_exiting_signal_handler is an evil hack
 // to avoid infinite SIGABRT recursion in the signal handler
 // due to poisoned locks or mach-o kernel not supporting locks in signals
 // or something like that. idk
-#  define Lock_search_state()    if (!g_in_exiting_signal_handler) { I_lock_mutex(&replayquerymutex); }
-#  define Unlock_search_state()  if (!g_in_exiting_signal_handler) { I_unlock_mutex(replayquerymutex); }
+#  define Lock_search_state()    if (!g_in_exiting_signal_handler) { I_LockMutex(&replayquerymutex); }
+#  define Unlock_search_state()  if (!g_in_exiting_signal_handler) { I_UnlockMutex(replayquerymutex); }
 #else/*HAVE_THREADS*/
 #  define Lock_search_state()
 #  define Unlock_search_state()
@@ -4088,7 +4088,10 @@ static void LoadReplayNames(void)
 	Unlock_search_state();
 
 #ifdef HAVE_THREADS
-	I_spawn_thread("replay-names-load", ReplayNamesLoadThread, replaydirpath);
+	if (!I_SpawnThread("replay-names-load", ReplayNamesLoadThread, replaydirpath))
+	{
+		free(replaydirpath);
+	}
 #else
 	ReplayNamesLoadThread(replaydirpath);
 #endif
@@ -6684,11 +6687,11 @@ static void M_EndGame(INT32 choice)
 void M_SetWaitingMode(int mode)
 {
 #ifdef HAVE_THREADS
-	I_lock_mutex(&m_menu_mutex);
+	I_LockMutex(&m_menu_mutex);
 #endif
 	m_waiting_mode = mode;
 #ifdef HAVE_THREADS
-	I_unlock_mutex(m_menu_mutex);
+	I_UnlockMutex(m_menu_mutex);
 #endif
 }
 
@@ -6697,11 +6700,11 @@ int M_GetWaitingMode(void)
 	int mode;
 
 #ifdef HAVE_THREADS
-	I_lock_mutex(&m_menu_mutex);
+	I_LockMutex(&m_menu_mutex);
 #endif
 	mode = m_waiting_mode;
 #ifdef HAVE_THREADS
-	I_unlock_mutex(m_menu_mutex);
+	I_UnlockMutex(m_menu_mutex);
 #endif
 
 	return mode;
@@ -6713,20 +6716,23 @@ static void Spawn_masterserver_thread(const char *name, void (*thread)(int*))
 {
 	int *id = malloc(sizeof *id);
 
-	I_lock_mutex(&ms_QueryId_mutex);
+	I_LockMutex(&ms_QueryId_mutex);
 	*id = ms_QueryId;
-	I_unlock_mutex(ms_QueryId_mutex);
+	I_UnlockMutex(ms_QueryId_mutex);
 
-	I_spawn_thread(name, (I_thread_fn)thread, id);
+	if (!I_SpawnThread(name, (I_ThreadFn)thread, id))
+	{
+		free(id);
+	}
 }
 
 static int Same_instance(int id)
 {
 	int okay;
 
-	I_lock_mutex(&ms_QueryId_mutex);
+	I_LockMutex(&ms_QueryId_mutex);
 	okay = ( id == ms_QueryId );
-	I_unlock_mutex(ms_QueryId_mutex);
+	I_UnlockMutex(ms_QueryId_mutex);
 
 	return okay;
 }
@@ -6755,9 +6761,9 @@ static void Fetch_servers_thread(int *id)
 			M_SetWaitingMode(M_NOT_WAITING);
 
 #ifdef HAVE_THREADS
-			I_lock_mutex(&ms_ServerList_mutex);
+			I_LockMutex(&ms_ServerList_mutex);
 			ms_ServerList = server_list;
-			I_unlock_mutex(ms_ServerList_mutex);
+			I_UnlockMutex(ms_ServerList_mutex);
 #else
 			CL_QueryServerList(server_list);
 			free(server_list);
@@ -6790,7 +6796,7 @@ static void M_SearchServerList(void)
 	serverlistsearchedcount = 0;
 
 #ifdef HAVE_THREADS
-	I_lock_mutex(&ms_ServerList_mutex);
+	I_LockMutex(&ms_ServerList_mutex);
 #endif
 
 	for (UINT32 i = 0; i < serverlistcount; ++i)
@@ -6801,7 +6807,7 @@ static void M_SearchServerList(void)
 	}
 
 #ifdef HAVE_THREADS
-	I_unlock_mutex(ms_ServerList_mutex);
+	I_UnlockMutex(ms_ServerList_mutex);
 #endif
 
 	if (menuinput.length > 0)
@@ -7167,11 +7173,11 @@ static void M_CheckMODVersion(int id)
 	{
 		sprintf(updatestring, UPDATE_ALERT_STRING, VERSIONSTRING, updatecheck);
 #ifdef HAVE_THREADS
-		I_lock_mutex(&m_menu_mutex);
+		I_LockMutex(&m_menu_mutex);
 #endif
 		M_StartMessage(updatestring, NULL, MM_NOTHING);
 #ifdef HAVE_THREADS
-		I_unlock_mutex(m_menu_mutex);
+		I_UnlockMutex(m_menu_mutex);
 #endif
 	}
 }
@@ -7217,13 +7223,13 @@ static void M_ConnectMenu(INT32 choice)
 	itemOn = 0;
 
 #if defined (MASTERSERVER) && defined (HAVE_THREADS)
-	I_lock_mutex(&ms_QueryId_mutex);
+	I_LockMutex(&ms_QueryId_mutex);
 	{
 		ms_QueryId++;
 	}
-	I_unlock_mutex(ms_QueryId_mutex);
+	I_UnlockMutex(ms_QueryId_mutex);
 
-	I_lock_mutex(&ms_ServerList_mutex);
+	I_LockMutex(&ms_ServerList_mutex);
 	{
 		if (ms_ServerList)
 		{
@@ -7231,7 +7237,7 @@ static void M_ConnectMenu(INT32 choice)
 			ms_ServerList = NULL;
 		}
 	}
-	I_unlock_mutex(ms_ServerList_mutex);
+	I_UnlockMutex(ms_ServerList_mutex);
 
 #ifdef UPDATE_ALERT
 	Spawn_masterserver_thread("check-new-version", Check_new_version_thread);

src/m_menu.h

@@ -215,7 +215,7 @@ void M_SetupNextMenu(menu_t *menudef);
 void M_ClearMenus(boolean callexitmenufunc);
 
 #ifdef HAVE_THREADS
-extern I_mutex m_menu_mutex;
+extern I_Mutex m_menu_mutex;
 #endif
 
 extern menu_t *currentMenu;

src/mserv.c

@@ -41,11 +41,11 @@ static time_t  MSLastPing;
 static char *MSRules;
 
 #ifdef HAVE_THREADS
-static I_mutex MSMutex;
-static I_cond  MSCond;
+static I_Mutex MSMutex;
+static I_Cond  MSCond;
 
-#  define Lock_state()   I_lock_mutex  (&MSMutex)
-#  define Unlock_state() I_unlock_mutex (MSMutex)
+#  define Lock_state()   I_LockMutex  (&MSMutex)
+#  define Unlock_state() I_UnlockMutex (MSMutex)
 #else/*HAVE_THREADS*/
 #  define Lock_state()
 #  define Unlock_state()
@@ -90,10 +90,10 @@ consvar_t cv_masterserver_nagattempts = {"masterserver_nagattempts", "5", CV_SAV
 
 #if defined (MASTERSERVER) && defined (HAVE_THREADS)
 int           ms_QueryId = 0;
-I_mutex       ms_QueryId_mutex;
+I_Mutex       ms_QueryId_mutex;
 
 msg_server_t *ms_ServerList = NULL;
-I_mutex       ms_ServerList_mutex;
+I_Mutex       ms_ServerList_mutex;
 #endif
 
 UINT16 current_port = 0;
@@ -129,11 +129,11 @@ void AddMServCommands(void)
 static void WarnGUI (void)
 {
 #ifdef HAVE_THREADS
-	I_lock_mutex(&m_menu_mutex);
+	I_LockMutex(&m_menu_mutex);
 #endif
 	M_PopupMasterServerConnectError();
 #ifdef HAVE_THREADS
-	I_unlock_mutex(m_menu_mutex);
+	I_UnlockMutex(m_menu_mutex);
 #endif
 }
 
@@ -168,12 +168,12 @@ char *GetMODVersion(int id)
 	c = HMS_compare_mod_version(buffer, 16);
 
 #ifdef HAVE_THREADS
-	I_lock_mutex(&ms_QueryId_mutex);
+	I_LockMutex(&ms_QueryId_mutex);
 	{
 		if (id != ms_QueryId)
 			c = -1;
 	}
-	I_unlock_mutex(ms_QueryId_mutex);
+	I_UnlockMutex(ms_QueryId_mutex);
 #endif
 
 	if (c > 0)
@@ -341,7 +341,7 @@ Finish_unlist (void)
 		Unlock_state();
 
 #ifdef HAVE_THREADS
-		I_wake_all_cond(&MSCond);
+		I_WakeAllCond(&MSCond);
 #endif
 	}
 }
@@ -377,7 +377,7 @@ New_server_id (void)
 	Lock_state();
 	{
 		*id = ++MSId;
-		I_wake_all_cond(&MSCond);
+		I_WakeAllCond(&MSCond);
 	}
 	Unlock_state();
 	return id;
@@ -392,7 +392,7 @@ Register_server_thread (int *id)
 	{
 		/* wait for previous unlist to finish */
 		while (*id == MSId && MSRegistered)
-			I_hold_cond(&MSCond, MSMutex);
+			I_HoldCond(&MSCond, MSMutex);
 
 		same = ( *id == MSId );/* it could have been a while */
 	}
@@ -444,7 +444,7 @@ Change_masterserver_thread (char *api)
 	Lock_state();
 	{
 		while (MSRegistered)
-			I_hold_cond(&MSCond, MSMutex);
+			I_HoldCond(&MSCond, MSMutex);
 	}
 	Unlock_state();
 
@@ -464,9 +464,9 @@ void RegisterServer(void)
 {
 #ifdef MASTERSERVER
 #ifdef HAVE_THREADS
-	I_spawn_thread(
+	(void)!I_SpawnThread(
 			"register-server",
-			(I_thread_fn)Register_server_thread,
+			(I_ThreadFn)Register_server_thread,
 			New_server_id()
 	);
 #else
@@ -478,9 +478,9 @@ void RegisterServer(void)
 static void UpdateServer(void)
 {
 #ifdef HAVE_THREADS
-	I_spawn_thread(
+	(void)!I_SpawnThread(
 			"update-server",
-			(I_thread_fn)Update_server_thread,
+			(I_ThreadFn)Update_server_thread,
 			Server_id()
 	);
 #else
@@ -492,9 +492,9 @@ void UnregisterServer(void)
 {
 #ifdef MASTERSERVER
 #ifdef HAVE_THREADS
-	I_spawn_thread(
+	(void)!I_SpawnThread(
 			"unlist-server",
-			(I_thread_fn)Unlist_server_thread,
+			(I_ThreadFn)Unlist_server_thread,
 			Server_id()
 	);
 #else
@@ -557,14 +557,18 @@ void MasterClient_Ticker(void)
 static void
 Set_api (const char *api)
 {
+	char *dapi = strdup(api);
 #ifdef HAVE_THREADS
-	I_spawn_thread(
-			"change-masterserver",
-			(I_thread_fn)Change_masterserver_thread,
-			strdup(api)
-	);
+	if (!I_SpawnThread(
+		"change-masterserver",
+		(I_ThreadFn)Change_masterserver_thread,
+					   dapi
+	))
+	{
+		free(dapi);
+	}
 #else
-	Finish_masterserver_change(strdup(api));
+	Finish_masterserver_change(dapi);
 #endif
 }
 
@@ -572,9 +576,9 @@ void
 Get_rules (void)
 {
 #ifdef HAVE_THREADS
-	I_spawn_thread(
-		"get-masterserver-rules",
-		(I_thread_fn)Get_masterserver_rules_thread,
+	(void)!I_SpawnThread(
+			"get-masterserver-rules",
+			(I_ThreadFn)Get_masterserver_rules_thread,
 				   NULL
 	);
 #else

src/mserv.h

@@ -69,10 +69,10 @@ extern consvar_t cv_rendezvousserver;
 
 #ifdef HAVE_THREADS
 extern int           ms_QueryId;
-extern I_mutex       ms_QueryId_mutex;
+extern I_Mutex       ms_QueryId_mutex;
 
 extern msg_server_t *ms_ServerList;
-extern I_mutex       ms_ServerList_mutex;
+extern I_Mutex       ms_ServerList_mutex;
 #endif
 #ifdef MASTERSERVER
 void RegisterServer(void);

src/r_draw.cpp

@@ -289,8 +289,14 @@ void R_GenerateBlendTables(void)
 	state->LocalPalette = static_cast<RGBA_t *>(memcpy(malloc(palsize), pLocalPalette, palsize));
 	state->gammaCorrectedPalette = static_cast<RGBA_t *>(memcpy(malloc(palsize), pGammaCorrectedPalette, palsize));
 
-	I_spawn_thread("blend-tables",
-			R_GenerateBlendTables_Thread, state);
+	if (!I_SpawnThread("blend-tables",
+			R_GenerateBlendTables_Thread, state))
+	{
+		free(state->gammaCorrectedPalette);
+		free(state->LocalPalette);
+		free(state);
+		I_Error("R_GenerateBlendTables: Failed to generate BlendTables\n"); // should we just retry on main thread instead?
+	}
 #else
 	struct GenerateBlendTables_State state = {pLocalPalette, pGammaCorrectedPalette};
 	R_GenerateBlendTables_Core(&state);

src/sdl/CMakeLists.txt

@@ -35,7 +35,6 @@ set(SRB2_SDL2_SOURCES
 	i_system.cpp
 	i_ttf.c
 	i_video.c
-	i_threads.c
 	#IMG_xpm.c
 	ogl_sdl.c
 

src/sdl/i_system.cpp

@@ -1896,8 +1896,8 @@ INT32 I_StartupSystem(void)
 		I_Fork();
 #endif
 #ifdef HAVE_THREADS
-	I_start_threads();
-	I_AddExitFunc(I_stop_threads);
+	I_StartThreads();
+	I_AddExitFunc(I_StopThreads);
 	I_ThreadPoolInit();
 	I_AddExitFunc(I_ThreadPoolShutdown);
 #endif

src/sdl/i_threads.c

@@ -1,360 +0,0 @@
-// SONIC ROBO BLAST 2 KART
-//-----------------------------------------------------------------------------
-// Copyright (C) 2020 by James R.
-//
-// This program is free software distributed under the
-// terms of the GNU General Public License, version 2.
-// See the 'LICENSE' file for more details.
-//-----------------------------------------------------------------------------
-/// \file  i_threads.c
-/// \brief Multithreading abstraction
-
-#ifdef HAVE_THREADS
-
-#include "../doomdef.h"
-#include "../i_threads.h"
-
-#include <SDL.h>
-
-typedef void * (*Create_fn)(void);
-
-struct Link;
-struct Thread;
-
-typedef struct Link   * Link;
-typedef struct Thread * Thread;
-
-struct Link
-{
-	void * data;
-	Link   next;
-	Link   prev;
-};
-
-struct Thread
-{
-	I_thread_fn   entry;
-	void        * userdata;
-
-	SDL_Thread  * thread;
-};
-
-static Link    i_thread_pool;
-static Link    i_mutex_pool;
-static Link    i_cond_pool;
-
-static I_mutex        i_thread_pool_mutex;
-static I_mutex        i_mutex_pool_mutex;
-static I_mutex        i_cond_pool_mutex;
-
-static SDL_atomic_t   i_threads_running = {1};
-
-static Link
-Insert_link (
-		Link * head,
-		Link   link
-){
-	link->prev = NULL;
-	link->next = (*head);
-	if ((*head))
-		(*head)->prev = link;
-	(*head)    = link;
-	return link;
-}
-
-static void
-Free_link (
-		Link * head,
-		Link   link
-){
-	if (link->prev)
-		link->prev->next = link->next;
-	else
-		(*head) = link->next;
-
-	if (link->next)
-		link->next->prev = link->prev;
-
-	free(link->data);
-	free(link);
-}
-
-static Link
-New_link (void *data)
-{
-	Link link;
-
-	link = malloc(sizeof *link);
-
-	if (! link)
-		abort();
-
-	link->data = data;
-
-	return link;
-}
-
-static void *
-Identity (
-		Link      *  pool_anchor,
-		I_mutex      pool_mutex,
-
-		void      ** anchor,
-
-		Create_fn    create_fn
-){
-	void * id;
-
-	id = SDL_AtomicGetPtr(anchor);
-
-	if (! id)
-	{
-		I_lock_mutex(&pool_mutex);
-		{
-			id = SDL_AtomicGetPtr(anchor);
-
-			if (! id)
-			{
-				id = (*create_fn)();
-
-				if (! id)
-					abort();
-
-				Insert_link(pool_anchor, New_link(id));
-
-				SDL_AtomicSetPtr(anchor, id);
-			}
-		}
-		I_unlock_mutex(pool_mutex);
-	}
-
-	return id;
-}
-
-static int
-Worker (
-		Link link
-){
-	Thread th;
-
-	th = link->data;
-
-	(*th->entry)(th->userdata);
-
-	if (SDL_AtomicGet(&i_threads_running))
-	{
-		I_lock_mutex(&i_thread_pool_mutex);
-		{
-			if (SDL_AtomicGet(&i_threads_running))
-			{
-				SDL_DetachThread(th->thread);
-				Free_link(&i_thread_pool, link);
-			}
-		}
-		I_unlock_mutex(i_thread_pool_mutex);
-	}
-
-	return 0;
-}
-
-void
-I_spawn_thread (
-		const char  * name,
-		I_thread_fn   entry,
-		void        * userdata
-){
-	Link   link;
-	Thread th;
-
-	th = malloc(sizeof *th);
-
-	if (! th)
-		abort();/* this is pretty GNU of me */
-
-	th->entry    = entry;
-	th->userdata = userdata;
-
-	I_lock_mutex(&i_thread_pool_mutex);
-	{
-		link = Insert_link(&i_thread_pool, New_link(th));
-
-		if (SDL_AtomicGet(&i_threads_running))
-		{
-			th->thread = SDL_CreateThread(
-					(SDL_ThreadFunction)Worker,
-					name,
-					link
-			);
-
-			if (! th->thread)
-				abort();
-		}
-	}
-	I_unlock_mutex(i_thread_pool_mutex);
-}
-
-int
-I_thread_is_stopped (void)
-{
-	return ( ! SDL_AtomicGet(&i_threads_running) );
-}
-
-void
-I_start_threads (void)
-{
-	i_thread_pool_mutex = SDL_CreateMutex();
-	i_mutex_pool_mutex  = SDL_CreateMutex();
-	i_cond_pool_mutex   = SDL_CreateMutex();
-
-	if (!(
-				i_thread_pool_mutex &&
-				i_mutex_pool_mutex  &&
-				i_cond_pool_mutex
-	)){
-		abort();
-	}
-}
-
-void
-I_stop_threads (void)
-{
-	Link        link;
-	Link        next;
-
-	Thread      th;
-	SDL_mutex * mutex;
-	SDL_cond  * cond;
-
-	if (i_threads_running.value)
-	{
-		/* rely on the good will of thread-san */
-		SDL_AtomicSet(&i_threads_running, 0);
-
-		I_lock_mutex(&i_thread_pool_mutex);
-		{
-			for (
-					link = i_thread_pool;
-					link;
-					link = next
-			){
-				next = link->next;
-				th   = link->data;
-
-				SDL_WaitThread(th->thread, NULL);
-
-				free(th);
-				free(link);
-			}
-		}
-		I_unlock_mutex(i_thread_pool_mutex);
-
-		for (
-				link = i_mutex_pool;
-				link;
-				link = next
-		){
-			next  = link->next;
-			mutex = link->data;
-
-			SDL_DestroyMutex(mutex);
-
-			free(link);
-		}
-
-		for (
-				link = i_cond_pool;
-				link;
-				link = next
-		){
-			next = link->next;
-			cond = link->data;
-
-			SDL_DestroyCond(cond);
-
-			free(link);
-		}
-
-		SDL_DestroyMutex(i_thread_pool_mutex);
-		SDL_DestroyMutex(i_mutex_pool_mutex);
-		SDL_DestroyMutex(i_cond_pool_mutex);
-	}
-}
-
-void
-I_lock_mutex (
-		I_mutex * anchor
-){
-	SDL_mutex * mutex;
-
-	mutex = Identity(
-			&i_mutex_pool,
-			i_mutex_pool_mutex,
-			anchor,
-			(Create_fn)SDL_CreateMutex
-	);
-
-	if (SDL_LockMutex(mutex) == -1)
-		abort();
-}
-
-void
-I_unlock_mutex (
-		I_mutex id
-){
-	if (SDL_UnlockMutex(id) == -1)
-		abort();
-}
-
-void
-I_hold_cond (
-		I_cond  * cond_anchor,
-		I_mutex   mutex_id
-){
-	SDL_cond * cond;
-
-	cond = Identity(
-			&i_cond_pool,
-			i_cond_pool_mutex,
-			cond_anchor,
-			(Create_fn)SDL_CreateCond
-	);
-
-	if (SDL_CondWait(cond, mutex_id) == -1)
-		abort();
-}
-
-void
-I_wake_one_cond (
-		I_cond * anchor
-){
-	SDL_cond * cond;
-
-	cond = Identity(
-			&i_cond_pool,
-			i_cond_pool_mutex,
-			anchor,
-			(Create_fn)SDL_CreateCond
-	);
-
-	if (SDL_CondSignal(cond) == -1)
-		abort();
-}
-
-void
-I_wake_all_cond (
-		I_cond * anchor
-){
-	SDL_cond * cond;
-
-	cond = Identity(
-			&i_cond_pool,
-			i_cond_pool_mutex,
-			anchor,
-			(Create_fn)SDL_CreateCond
-	);
-
-	if (SDL_CondBroadcast(cond) == -1)
-		abort();
-}
-
-#endif // HAVE_THREADS

src/z_zone.cpp

@@ -75,6 +75,8 @@ typedef struct memblock_s
 #define MEMORY(x) (void *)((uintptr_t)(x) + sizeof(memblock_t) + ALIGNPAD)
 #define MEMBLOCK(x) (memblock_t *)((uintptr_t)(x) - ALIGNPAD - sizeof(memblock_t))
 
+static thread_handle_t main_thread;
+
 // both the head and tail of the zone memory block list
 static memblock_t head;
 
@@ -108,6 +110,7 @@ static void Command_Memdump_f(void);
 void Z_Init(void)
 {
 	size_t total, memfree;
+	main_thread = I_GetCurrentThread();
 
 	memset(&head, 0x00, sizeof(head));
 
@@ -143,6 +146,8 @@ void Z_Free(void *ptr)
 {
 	memblock_t *block;
 
+	I_Assert(I_GetCurrentThread() == main_thread);
+
 	if (ptr == NULL)
 		return;
 
@@ -237,6 +242,8 @@ void *Z_Malloc(size_t size, INT32 tag, void *user)
 	memblock_t *block;
 	void *ptr;
 
+	I_Assert(I_GetCurrentThread() == main_thread);
+
 #ifdef ZDEBUG2
 	CONS_Debug(DBG_MEMORY, "Z_Malloc %s:%d\n", file, line);
 #endif
@@ -300,6 +307,8 @@ void *Z_Calloc2(size_t size, INT32 tag, void *user, const char *file, INT32 line
 void *Z_Calloc(size_t size, INT32 tag, void *user)
 #endif
 {
+	I_Assert(I_GetCurrentThread() == main_thread);
+
 #ifdef VALGRIND_MEMPOOL_ALLOC
 	Z_calloc = true;
 #endif
@@ -335,6 +344,8 @@ void *Z_Realloc(void *ptr, size_t size, INT32 tag, void *user)
 	memblock_t *block;
 	size_t copysize;
 
+	I_Assert(I_GetCurrentThread() == main_thread);
+
 #ifdef ZDEBUG2
 	CONS_Debug(DBG_MEMORY, "Z_Realloc %s:%d\n", file, line);
 #endif
@@ -414,6 +425,8 @@ void Z_FreeTags(INT32 lowtag, INT32 hightag)
 {
 	memblock_t *block, *next;
 
+	I_Assert(I_GetCurrentThread() == main_thread);
+
 #ifdef ZDEBUG
 	Z_CheckHeap2(file, line);
 #else
@@ -447,6 +460,8 @@ void Z_IterateTags(INT32 lowtag, INT32 hightag, boolean (*iterfunc)(void *))
 {
 	memblock_t *block, *next;
 
+	I_Assert(I_GetCurrentThread() == main_thread);
+
 	if (!iterfunc)
 		I_Error("Z_IterateTags: no iterator function was given");