From d235c8914ce6dc8e57e5da130274149f8c0f7af7 Mon Sep 17 00:00:00 2001
From: Ivan Baravy <dunkaist@gmail.com>
Date: Sat, 1 Feb 2025 02:53:14 +0000
Subject: [PATCH] Fix ghost threads in CPU

* kernel: Make sf9 return TSTATE_FREE for invalid slots: 0, >255, free.
* menu: Ignore free slots even if other fields of proc_info look valid.
        Documentation (sysfuncs.txt) clearly states all the other info
        as invalid when slot_state is TSTATE_FREE.
* taskbar: Same as menu.
* cmm/lib/*: Same as menu.
* programs/macros.inc: Add TSTATE_* macros.
---
 kernel/trunk/kernel.asm                     | 19 +++++-----------
 programs/cmm/lib/kolibri.h                  |  1 +
 programs/cmm/lib/patterns/restart_process.h | 25 ++++++++++++---------
 programs/macros.inc                         | 11 ++++++++-
 programs/system/menu/trunk/menu.asm         |  9 ++++----
 programs/system/taskbar/trunk/drawappl.inc  |  2 ++
 6 files changed, 39 insertions(+), 28 deletions(-)

diff --git a/kernel/trunk/kernel.asm b/kernel/trunk/kernel.asm
index 3be8af1b0..68c8ac4b2 100644
--- a/kernel/trunk/kernel.asm
+++ b/kernel/trunk/kernel.asm
@@ -2320,23 +2320,16 @@ sys_cpuusage:
         jne     .no_who_am_i
         mov     ecx, [current_slot_idx]
 .no_who_am_i:
-        jecxz   .empty_slot
+        ; default value for (slot == 0) and (slot > 255)
+        mov     [ebx+process_information.slot_state], TSTATE_FREE
+        test    ecx, ecx
+        jz      .nofillbuf
         cmp     ecx, max_processes
-        ja      .empty_slot
+        ja      .nofillbuf
         mov     edx, ecx
         shl     edx, BSF sizeof.APPDATA
         cmp     [SLOT_BASE+edx+APPDATA.state], TSTATE_FREE
-        jnz     .thread_found
-.empty_slot:
-        ; zero buffer for an empty slot
-        push    edi
-        xor     eax, eax
-        mov     edi, ebx
-        movi    ecx, sizeof.process_information
-        rep stosb
-        pop     edi
-        jmp     .nofillbuf
-.thread_found:
+        jz      .nofillbuf
 ; +4: word: position of the window of thread in the window stack
         mov     ax, [WIN_STACK + ecx * 2]
         mov     [ebx+process_information.window_stack_position], ax
diff --git a/programs/cmm/lib/kolibri.h b/programs/cmm/lib/kolibri.h
index 46c036861..b8f063ee7 100644
--- a/programs/cmm/lib/kolibri.h
+++ b/programs/cmm/lib/kolibri.h
@@ -79,6 +79,7 @@ dword  I_Path       =   #__path;
 
 #define CLOSE_BTN 1
 
+#define TSTATE_FREE 9
 //-------------------------------------------------------------------------
 
 #include "../lib/system.h"
diff --git a/programs/cmm/lib/patterns/restart_process.h b/programs/cmm/lib/patterns/restart_process.h
index 29c00bbb8..f4ad3d754 100644
--- a/programs/cmm/lib/patterns/restart_process.h
+++ b/programs/cmm/lib/patterns/restart_process.h
@@ -15,10 +15,12 @@ enum {
 :bool CheckProcessExists(dword proc_name) {
 	int i;
 	proc_info Process;
-	for (i=0; i<MAX_PROCESS_COUNT; i++;)
+	for (i=0; i<MAX_PROCESS_COUNT; i++)
 	{
 		GetProcessInfo(#Process, i);
-		if (strcmpi(#Process.name, proc_name)==0) return 1;
+		if (Process.status_slot != TSTATE_FREE)
+		&& (strcmpi(#Process.name, proc_name)==0)
+			return 1;
 	}
 	return 0;
 }
@@ -26,12 +28,13 @@ enum {
 :void KillProcessByName(dword proc_name, byte multiple) {
 	int i;
 	proc_info Process;
-	for (i=0; i<MAX_PROCESS_COUNT; i++;)
+	for (i=0; i<MAX_PROCESS_COUNT; i++)
 	{
 		GetProcessInfo(#Process, i);
-		if (strcmpi(#Process.name, proc_name)==0) 
-		{ 
-			KillProcess(Process.ID); 
+		if (Process.status_slot != TSTATE_FREE)
+		&& (strcmpi(#Process.name, proc_name)==0)
+		{
+			KillProcess(Process.ID);
 			if (multiple==SINGLE) break;
 		}
 	}
@@ -40,10 +43,12 @@ enum {
 :int GetProcessesCount(dword proc_name) {
 	int i, count=0;
 	proc_info Process;
-	for (i=0; i<MAX_PROCESS_COUNT; i++;)
+	for (i=0; i<MAX_PROCESS_COUNT; i++)
 	{
 		GetProcessInfo(#Process, i);
-		if (strcmpi(#Process.name, proc_name)==0) count++;
+		if (Process.status_slot != TSTATE_FREE)
+		&& (strcmpi(#Process.name, proc_name)==0)
+			count++;
 	}
 	return count;
 }
@@ -57,7 +62,7 @@ enum {
 	int i;
 	proc_info Process, Self;
 	GetProcessInfo(#Self, -1);
-	for (i=0; i<MAX_PROCESS_COUNT; i++;)
+	for (i=0; i<MAX_PROCESS_COUNT; i++)
 	{
 		GetProcessInfo(#Process, i);
 		if (Process.name) 
@@ -68,4 +73,4 @@ enum {
 	RunProgram("/sys/launcher", NULL);
 }
 
-#endif
\ No newline at end of file
+#endif
diff --git a/programs/macros.inc b/programs/macros.inc
index 92a4deab0..5bd3957d7 100644
--- a/programs/macros.inc
+++ b/programs/macros.inc
@@ -450,6 +450,15 @@ struct BOX
   height dd ?
 ends
 
+; Thread states:
+TSTATE_RUNNING        = 0
+TSTATE_RUN_SUSPENDED  = 1
+TSTATE_WAIT_SUSPENDED = 2
+TSTATE_ZOMBIE         = 3
+TSTATE_TERMINATING    = 4
+TSTATE_WAITING        = 5
+TSTATE_FREE           = 9
+
 ; structures used in KolibriOS
 struct process_information
   cpu_usage               dd ?  ; +0
@@ -461,7 +470,7 @@ struct process_information
   used_memory             dd ?  ; +26
   PID                     dd ?  ; +30
   box                     BOX   ; +34
-  slot_state              dw ?  ; +50
+  slot_state              dw ?  ; +50   TSTATE_*
                           dw ?  ; +52
   client_box              BOX   ; +54
   wnd_state               db ?  ; +70
diff --git a/programs/system/menu/trunk/menu.asm b/programs/system/menu/trunk/menu.asm
index 482464e48..d74e49e5a 100644
--- a/programs/system/menu/trunk/menu.asm
+++ b/programs/system/menu/trunk/menu.asm
@@ -783,13 +783,14 @@ align 4
 .loop:
 	push	ecx
 	mcall	9,procinfo
+        cmp     word[ebx+50], TSTATE_FREE
+        je      @f
 	mov	eax,[menu_mame]
 	cmp	[ebx+10],eax
 	jne	@f
-	; temporary to fit into 3 IMG sectors
-	;mov	ax,[menu_mame+4]
-	;cmp	[ebx+14],ax
-	;jne	@f
+	mov	ax,[menu_mame+4]
+	cmp	[ebx+14],ax
+	jne	@f
 	cmp	ecx,[active_process]
 	je	@f
 ; dph ecx
diff --git a/programs/system/taskbar/trunk/drawappl.inc b/programs/system/taskbar/trunk/drawappl.inc
index f7bd89743..67f0238d3 100644
--- a/programs/system/taskbar/trunk/drawappl.inc
+++ b/programs/system/taskbar/trunk/drawappl.inc
@@ -28,6 +28,8 @@ align 4
 need_window_tab:
 ; in: ebx->process info
 ; out: ZF set <=> do not draw
+        cmp     byte [ebx + process_information.slot_state], TSTATE_FREE
+        jz      .nodraw
         cmp     byte [ebx + process_information.process_name], '@'
         jz      .nodraw
 ; do not draw undefined (zero-sized) windows